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Article Title, Author/Curator’s Name and Article Views >1,000, 4/2012 – 1/2019 @pharmaceuticalintelligence.com

 

Reporter: Aviva Lev-Ari, PhD, RN

 

Expert, Author, Writer’s Initials

Name & Bio

Roles

@LPBI Group

LHB Larry Bernstein, MD, FACP,

 

Member of the Board

Expert, Author, Writer – All Specialties of Medicine & Pathology

Content Consultant to Series B,C,D,E

Editor, Series D, Vol. 1, Series E, Vols 2,3,

Co-Editor – BioMed E-Series 13 of the 16 Vols

JDP Justin D. Pearlman, AB, MD, ME, PhD, MA, FACC,

 

Expert, Author, Writer, All Specialties of Medicine, Cardiology and Cardiac Imaging

Content Consultant for SERIES A, Cardiovascular Diseases Co-Editor: Vols 2,3,4,5,6

ALA Aviva Lev-Ari, PhD, RN,

-Ex – SRI, Int’l

-Ex – MITRE

-Ex – McGraw-Hill

Director and Founder

Editor-in-Chief, @pharmaceuticalintelligence.com

Methodologies Developer:

  • Journal Platform Architect,
  • CURATION of Scientific Findings Modules,
  • REALTIME eProceedings Digital 1-Click Publishing

Expert, Author, Writer:

  • Analytics
  • Molecular Cardiology
  • Vascular Biology
TB Tilda Barliya, PhD,

@BIU

Expert, Author, Writer: Nanotechnology for Drug Delivery

Co-Editor, Series C, Vols. 1,2

DN Dror Nir, PhD,

 

Expert, Author, Writer: Cancer & Medical Imaging Algorithms
ZR       
Ziv Raviv, PhD,
@Technion
Expert, Author, Writer: Biological Sciences, Cancer
ZS Zohi Sternberg, PhD, Expert, GUEST Author, Writer

 

Expert, GUEST Author, Writer

Neurological Sciences

SJW Stephen J. Williams, PhD Pharmacology, BSc Toxicology

Ex-Fox Chase

EAW – Cancer Biology

Co-Editor, Series A, Vol.1

Co-Editor, Series B, Genomics: Vols. 1,2

Co-Editor, Series C, Cancer, Vols. 1,2

DS Demet Sag, PhD, CRA, GCP,

 

Expert, Author, Writer: Genome Biology, Immunology, Biological Sciences: Cancer
SS Sudipta Saha, PhD,

 

Expert, Author, Writer: Reproductive Biology, Endocrinology, Bio-Instrumentation

Co-Editor, Series D, Volume 2, Infectious Diseases

AV Aviral Vatsa, PhD, MBBS

 

Expert, Author, Writer: Medical Sciences, Bone Disease, Human Sensation and Cellular Transduction: Physiology and Therapeutics

 

RS Ritu Saxena, PhD,

 

Expert, Author, Writer: Biological Sciences, Bone Disease, Cancer (Lung, Liver)
GST Gail S. Thornton, PhD(c),

Ex-MERCK

Contributing Editor, Author and Medical Writer

Co-Editor, Series E, Vol.1 Voices of Patients

RN Raphael Nir, PhD, MSM, MSc

Ex-ScheringPlough

– Expert, Author, Writer – Member of the Cancer Research Team: Brain Cancer, Liver Cancer, Cytokines

– CSO, SBH Sciences, Inc.

MB Michael R. Briggs, Ph.D.

Ex-Pfizer

– Expert, Author, Writer – Member of the Cancer Research Team: NASH

– CSO, Woodland Biosciences

AK Alan F. Kaul, R.Ph., Pharm.D, M.Sc., M.B.A., FCCP, Expert, Author, Writer

Ex-Director BWH Pharmacy

Expert, Author, Writer: Pharmacology – all aspects of Drug development and dispensation, Policy analyst
AS Anamika Sarkar, PhD,

 

Expert, Author, Writer: Computation Biology & Bioinformatics
MWF Marcus Feldman, PhD,

Stanford University, Biological Sciences, Center for Genomics

751
Research items
51,402
Reads
39,126
Citations
Member of the Board,

Scientific Counsel: Life Sciences,

Content Consultant Series B, Genomics, Vols. 1,2

Co-Editor, Vol. 2, NGS

 

Article Title and Views >1,000,

4/2012 – -1/2018

 

 

 

 

Home page / Archives

Authors

Curators

Reporters

by Name

 

Views

by 

eReaders

 

 

 

 

 

600,145

Is the Warburg Effect the Cause or the Effect of Cancer: A 21st Century View? LHB 16,720
Do Novel Anticoagulants Affect the PT/INR? The Cases of XARELTO (rivaroxaban) and PRADAXA (dabigatran)

JDP

ALA

13,225
Paclitaxel vs Abraxane (albumin-bound paclitaxel) TB 11,872
Recent comprehensive review on the role of ultrasound in breast cancer management DN 11,715
Clinical Indications for Use of Inhaled Nitric Oxide (iNO) in the Adult Patient Market: Clinical Outcomes after Use, Therapy Demand and Cost of Care ALA 7,045
Apixaban (Eliquis): Mechanism of Action, Drug Comparison and Additional Indications ALA 6,435
Mesothelin: An early detection biomarker for cancer (By Jack Andraka) TB 6,309
Our TEAM ALA 6,213
Akt inhibition for cancer treatment, where do we stand today? ZR 4,744
Biochemistry of the Coagulation Cascade and Platelet Aggregation: Nitric Oxide: Platelets, Circulatory Disorders, and Coagulation Effects LHB 4,508
Newer Treatments for Depression: Monoamine, Neurotrophic Factor & Pharmacokinetic Hypotheses ZS 4,188
AstraZeneca’s WEE1 protein inhibitor AZD1775 Shows Success Against Tumors with a SETD2 mutation SJW 4,128
Confined Indolamine 2, 3 dioxygenase (IDO) Controls the Hemeostasis of Immune Responses for Good and Bad DS 3,678
The Centrality of Ca(2+) Signaling and Cytoskeleton Involving Calmodulin Kinases and Ryanodine Receptors in Cardiac Failure, Arterial Smooth Muscle, Post-ischemic Arrhythmia, Similarities and Differences, and Pharmaceutical Targets LHB 3,652
FDA Guidelines For Developmental and Reproductive Toxicology (DART) Studies for Small Molecules SJW 3,625
Cardiovascular Diseases, Volume One: Perspectives on Nitric Oxide in Disease Mechanisms Multiple

Authors

3,575
Interaction of enzymes and hormones SS 3,546
AMPK Is a Negative Regulator of the Warburg Effect and Suppresses Tumor Growth In Vivo SJW 3,403
Causes and imaging features of false positives and false negatives on 18F-PET/CT in oncologic imaging DN 3,399
Introduction to Transdermal Drug Delivery (TDD) system and nanotechnology TB 3,371
Founder ALA 3,363
BioMed e-Series ALA 3,246
Signaling and Signaling Pathways LHB 3,178
Sexed Semen and Embryo Selection in Human Reproduction and Fertility Treatment SS 3,044
Alternative Designs for the Human Artificial Heart: Patients in Heart Failure – Outcomes of Transplant (donor)/Implantation (artificial) and Monitoring Technologies for the Transplant/Implant Patient in the Community

JDP

LHB

ALA

3,034
The mechanism of action of the drug ‘Acthar’ for Systemic Lupus Erythematosus (SLE) Dr. Karra 3,016
VISION ALA 2,988
Targeting the Wnt Pathway [7.11] LHB 2,961
Bone regeneration and nanotechnology AV 2,922
Pacemakers, Implantable Cardioverter Defibrillators (ICD) and Cardiac Resynchronization Therapy (CRT) ALA 2,892
The History and Creators of Total Parenteral Nutrition LHB 2,846
Funding, Deals & Partnerships ALA 2,708
Paclitaxel: Pharmacokinetic (PK), Pharmacodynamic (PD) and Pharmacogenpmics (PG) TB 2,700
LIK 066, Novartis, for the treatment of type 2 diabetes LHB 2,693
FDA Adds Cardiac Drugs to Watch List – TOPROL-XL® ALA 2,606
Mitochondria: Origin from oxygen free environment, role in aerobic glycolysis, metabolic adaptation LHB 2,579
Nitric Oxide and Platelet Aggregation Dr. Karra 2,550
Treatment Options for Left Ventricular Failure – Temporary Circulatory Support: Intra-aortic balloon pump (IABP) – Impella Recover LD/LP 5.0 and 2.5, Pump Catheters (Non-surgical) vs Bridge Therapy: Percutaneous Left Ventricular Assist Devices (pLVADs) and LVADs (Surgical) LHB 2,549
Isoenzymes in cell metabolic pathways LHB 2,535
“The Molecular pathology of Breast Cancer Progression” TB 2,491
In focus: Circulating Tumor Cells RS 2,465
Nitric Oxide Function in Coagulation – Part II LHB 2,444
Monoclonal Antibody Therapy and Market DS 2,443
Update on FDA Policy Regarding 3D Bioprinted Material SJW 2,410
Journal PharmaceuticalIntelligence.com ALA 2,340
A Primer on DNA and DNA Replication LHB 2,323
Pyrroloquinoline quinone (PQQ) – an unproved supplement LHB 2,294
Integrins, Cadherins, Signaling and the Cytoskeleton LHB 2,265
Evolution of Myoglobin and Hemoglobin LHB 2,251
DNA Structure and Oligonucleotides LHB 2,187
Lipid Metabolism LHB 2,176
Non-small Cell Lung Cancer drugs – where does the Future lie? RS 2,143
Biosimilars: CMC Issues and Regulatory Requirements ALA 2,101
The SCID Pig: How Pigs are becoming a Great Alternate Model for Cancer Research SJW 2,092
About ALA 2,076
Sex Hormones LHB 2,066
CD47: Target Therapy for Cancer TB 2,041
Peroxisome proliferator-activated receptor (PPAR-gamma) Receptors Activation: PPARγ transrepression for Angiogenesis in Cardiovascular Disease and PPARγ transactivation for Treatment of Diabetes ALA 2,017
Swiss Paraplegic Centre, Nottwil, Switzerland – A World-Class Clinic for Spinal Cord Injuries GST 1,989
Introduction to Tissue Engineering; Nanotechnology applications TB 1,964
Problems of vegetarianism SS 1,940
The History of Infectious Diseases and Epidemiology in the late 19th and 20th Century LHB 1,817
The top 15 best-selling cancer drugs in 2022 & Projected Sales in 2020 of World’s Top Ten Oncology Drugs ALA 1,816
Nanotechnology: Detecting and Treating metastatic cancer in the lymph node TB 1,812
Unique Selling Proposition (USP) — Building Pharmaceuticals Brands ALA 1,809
Wnt/β-catenin Signaling [7.10] LHB 1,777
The role of biomarkers in the diagnosis of sepsis and patient management LHB 1,766
Neonatal Pathophysiology LHB 1,718
Nanotechnology and MRI imaging TB 1,672
Cardiovascular Complications: Death from Reoperative Sternotomy after prior CABG, MVR, AVR, or Radiation; Complications of PCI; Sepsis from Cardiovascular Interventions JDP

ALA

1,659
Ultrasound-based Screening for Ovarian Cancer DN 1,655
Justin D. Pearlman, AB, MD, ME, PhD, MA, FACC, Expert, Author, Writer, Editor & Content Consultant for e-SERIES A: Cardiovascular Diseases JDP 1,653
Scientific and Medical Affairs Chronological CV ALA 1,619
Competition in the Ecosystem of Medical Devices in Cardiac and Vascular Repair: Heart Valves, Stents, Catheterization Tools and Kits for Open Heart and Minimally Invasive Surgery (MIS) ALA 1,609
Stenting for Proximal LAD Lesions ALA 1,603
Mitral Valve Repair: Who is a Patient Candidate for a Non-Ablative Fully Non-Invasive Procedure? JDP

ALA

1,602
Nitric Oxide, Platelets, Endothelium and Hemostasis (Coagulation Part II) LHB 1,597
Outcomes in High Cardiovascular Risk Patients: Prasugrel (Effient) vs. Clopidogrel (Plavix); Aliskiren (Tekturna) added to ACE or added to ARB LHB 1,588
Diet and Diabetes LHB 1,572
Clinical Trials Results for Endothelin System: Pathophysiological role in Chronic Heart Failure, Acute Coronary Syndromes and MI – Marker of Disease Severity or Genetic Determination? ALA 1,546
Dealing with the Use of the High Sensitivity Troponin (hs cTn) Assays LHB 1,540
Biosimilars: Intellectual Property Creation and Protection by Pioneer and by Biosimilar Manufacturers ALA 1,534
Altitude Adaptation LHB 1,527
Baby’s microbiome changing due to caesarean birth and formula feeding SS 1,498
Interview with the co-discoverer of the structure of DNA: Watson on The Double Helix and his changing view of Rosalind Franklin ALA 1,488
Triple Antihypertensive Combination Therapy Significantly Lowers Blood Pressure in Hard-to-Treat Patients with Hypertension and Diabetes ALA 1,476
IDO for Commitment of a Life Time: The Origins and Mechanisms of IDO, indolamine 2, 3-dioxygenase DS 1,469
CRISPR/Cas9: Contributions on Endoribonuclease Structure and Function, Role in Immunity and Applications in Genome Engineering LHB 1,468
Cancer Signaling Pathways and Tumor Progression: Images of Biological Processes in the Voice of a Pathologist Cancer Expert LHB 1,452
Signaling transduction tutorial LHB 1,443
Diagnostic Evaluation of SIRS by Immature Granulocytes LHB 1,440
UPDATED: PLATO Trial on ACS: BRILINTA (ticagrelor) better than Plavix® (clopidogrel bisulfate): Lowering chances of having another heart attack ALA 1,426
Cardio-oncology and Onco-Cardiology Programs: Treatments for Cancer Patients with a History of Cardiovascular Disease ALA 1,424
Nanotechnology and Heart Disease TB 1,419
Aviva Lev-Ari, PhD, RN, Director and Founder ALA 1,416
Cardiotoxicity and Cardiomyopathy Related to Drugs Adverse Effects LHB 1,415
Nitric Oxide and it’s impact on Cardiothoracic Surgery TB 1,405
A New Standard in Health Care – Farrer Park Hospital, Singapore’s First Fully Integrated Healthcare/Hospitality Complex GST 1,402
Mitochondrial Damage and Repair under Oxidative Stress LHB 1,398
Ovarian Cancer and fluorescence-guided surgery: A report TB 1,395
Sex determination vs. Sex differentiation SS 1,393
LPBI Group ALA 1,372
Closing the Mammography gap DN 1,368
Cytoskeleton and Cell Membrane Physiology LHB 1,367
Crucial role of Nitric Oxide in Cancer RS 1,364
Medical 3D Printing ALA 1,332
Survivals Comparison of Coronary Artery Bypass Graft (CABG) and Percutaneous Coronary Intervention (PCI) / Coronary Angioplasty LHB 1,325
The Final Considerations of the Role of Platelets and Platelet Endothelial Reactions in Atherosclerosis and Novel Treatments LHB 1,310
Disruption of Calcium Homeostasis: Cardiomyocytes and Vascular Smooth Muscle Cells: The Cardiac and Cardiovascular Calcium Signaling Mechanism

LHB

JDP

ALA

1,301
Mitochondrial Dynamics and Cardiovascular Diseases RS 1,284
Nitric Oxide and Immune Responses: Part 2 AV 1,282
Liver Toxicity halts Clinical Trial of IAP Antagonist for Advanced Solid Tumors SJW 1,269
Inactivation of the human papillomavirus E6 or E7 gene in cervical carcinoma cells using a bacterial CRISPR/Cas ALA 1,261
Autophagy LHB 1,255
Mitochondrial fission and fusion: potential therapeutic targets? RS 1,246
Summary of Lipid Metabolism LHB 1,239
Nitric Oxide has a Ubiquitous Role in the Regulation of Glycolysis – with a Concomitant Influence on Mitochondrial Function LHB 1,233
Future of Calcitonin…? Dr. Karra 1,211
Transcatheter Aortic Valve Implantation (TAVI): FDA approves expanded indication for two transcatheter heart valves for patients at intermediate risk for death or complications associated with open-heart surgery ALA 1,197
Gamma Linolenic Acid (GLA) as a Therapeutic tool in the Management of Glioblastoma

RN

MB

1,193
Nanotechnology and HIV/AIDS Treatment TB 1,181
Patiromer – New drug for Hyperkalemia ALA 1,179
‘Gamifying’ Drug R&D: Boehringer Ingelheim, Sanofi, Eli Lilly ALA 1,177
A Patient’s Perspective: On Open Heart Surgery from Diagnosis and Intervention to Recovery Guest Author: Ferez S. Nallaseth, Ph.D. 1,173
Assessing Cardiovascular Disease with Biomarkers LHB 1,167
Development Of Super-Resolved Fluorescence Microscopy LHB 1,166
Ubiquitin-Proteosome pathway, Autophagy, the Mitochondrion, Proteolysis and Cell Apoptosis: Part III LHB 1,162
Atrial Fibrillation contributing factor to Death, Autopsy suggests CEO Dave Goldberg had heart arrhythmia before death ALA 1,159
Linus Pauling: On Lipoprotein(a) Patents and On Vitamin C ALA 1,156
Bystolic’s generic Nebivolol – Positive Effect on circulating Endothelial Progenitor Cells Endogenous Augmentation ALA 1,154
The History of Hematology and Related Sciences LHB 1,151
Heroes in Medical Research: Barnett Rosenberg and the Discovery of Cisplatin SJW 1,146
Overview of New Strategy for Treatment of T2DM: SGLT2 Inhibiting Oral Antidiabetic Agents AV 1,143
Imatinib (Gleevec) May Help Treat Aggressive Lymphoma: Chronic Lymphocytic Leukemia (CLL) ALA 1,140
Issues in Personalized Medicine in Cancer: Intratumor Heterogeneity and Branched Evolution Revealed by Multiregion Sequencing SJW 1,137
New England Compounding Center: A Family Business AK 1,120
EpCAM [7.4] LHB 1,113
Amyloidosis with Cardiomyopathy LHB 1,110
Can Mobile Health Apps Improve Oral-Chemotherapy Adherence? The Benefit of Gamification. SJW 1,095
Acoustic Neuroma, Neurinoma or Vestibular Schwannoma: Treatment Options ALA 1,089
Treatment of Refractory Hypertension via Percutaneous Renal Denervation ALA 1,088
Proteomics – The Pathway to Understanding and Decision-making in Medicine LHB 1,085
Low Bioavailability of Nitric Oxide due to Misbalance in Cell Free Hemoglobin in Sickle Cell Disease – A Computational Model AS 1,085
Pancreatic Cancer: Genetics, Genomics and Immunotherapy TB 1,083
A NEW ERA OF GENETIC MANIPULATION   DS 1,075
Targeting Mitochondrial-bound Hexokinase for Cancer Therapy ZR 1,074
Normal and Anomalous Coronary Arteries: Dual Source CT in Cardiothoracic Imaging JDP

ALA

1,062
Transdermal drug delivery (TDD) system and nanotechnology: Part II TB 1,057
Lung Cancer (NSCLC), drug administration and nanotechnology TB 1,046
Pharma World: The Pharmaceutical Industry in Southeast Asia – Pharma CPhI 20-22 March, 2013, Jakarta International Expo, Jakarta, Indonesia ALA 1,045
Nitric Oxide and Sepsis, Hemodynamic Collapse, and the Search for Therapeutic Options LHB 1,044
Targeted delivery of therapeutics to bone and connective tissues: current status and challenges- Part I AV 1,044
Press Coverage ALA 1,036
Carbohydrate Metabolism LHB 1,036
Open Abdominal Aortic Aneurysm (AAA) repair (OAR) vs. Endovascular AAA Repair (EVAR) in Chronic Kidney Disease Patients – Comparison of Surgery Outcomes LHB

ALA

1,032
In focus: Melanoma Genetics RS 1,018
Cholesteryl Ester Transfer Protein (CETP) Inhibitor: Potential of Anacetrapib to treat Atherosclerosis and CAD ALA 1,015
Medical Devices Start Ups in Israel: Venture Capital Sourced Locally – Rainbow Medical (GlenRock) & AccelMed (Arkin Holdings) ALA 1,007
The Development of siRNA-Based Therapies for Cancer ZR 1,003

Other related articles published in this Open Access Online Scientific Journal include the following:

FIVE years of e-Scientific Publishing @pharmaceuticalintellicence.com, Top Articles by Author and by e-Views >1,000, 4/27/2012 to 1/29/2018

https://pharmaceuticalintelligence.com/2017/04/28/five-years-of-e-scientific-publishing-pharmaceuticalintellicence-com-top-articles-by-author-and-by-e-views-1000-4272012-to-4272017/

Read Full Post »


Three Genres in e-Scientific Publishing AND Three Scientists’ Dilemmas

Curator: Aviva Lev-Ari, PhD, RN

 

That’s what I tell students. The way to succeed is to get born at the right time and in the right place. If you can do that then you are bound to succeed. You have to be receptive and have some talent as well.

Professor Sydney Brenner, a professor of Genetic medicine at the University of Cambridge and Nobel Laureate in Physiology or Medicine in 2002

 

 

Cell/Nature/Science

[CNS]

 Subscription-based Access

Open Access

  1. Online journals, to which scientists pay an upfront free to cover editing costs, which then ensure the work is available free to access for anyone in perpetuity

 

Curation of Scientific Findings

i.e., Kindle Direct Publishing [KDP] – Royalty-based system

  1. Free content to e-Readers
  2. Expert, Authors, Writers -Volunteers
  3. Editor -Voluneers
Confirming or disproving past studies Confirming or disproving past studies
Decades-long pursuit of a risky “moonshot” Decades-long pursuit of a risky “moonshot”
Trendy topics with Editors Trendy topics with Editors

 

Genres in e-Scientific Publishing

(A) Cell/Nature/Science

 – June 27, 2017

Elizabeth Dzeng — Feb 24th, 2014

  • http://www.cell.com/
  • http://www.sciencemag.org/
  • https://www.nature.com/
  • In 1998, Elsevier rolled out its plan for the internet age, which would come to be called “The Big Deal”. It offered electronic access to bundles of hundreds of journals at a time: a university would pay a set fee each year – according to a report based on freedom of information requests, Cornell University’s 2009 tab was just short of $2m – and any student or professor could download any journal they wanted through Elsevier’s website. Universities signed up en masse. …. Elsevier owned 24% of the scientific journal market, while Maxwell’s old partners Springer, and his crosstown rivals Wiley-Blackwell, controlled about another 12% each. These three companies accounted for half the market. (An Elsevier representative familiar with the report told me that by their own estimate they publish only 16% of the scientific literature.)  – June 27, 2017.  Elsevier published 420,000 papers last year, after receiving 1.5m submissions  – June 28, 2017 [numbers correction to 6/27/2017.]

(B) Open Access Journals and the Phenomenon

  1. Biochemistry
  2. Biophysics and Structural Biology
  3. Cancer Biology
  4. Cell Biology
  5. Computational and Systems Biology
  6. Developmental Biology and Stem Cells
  7. Epidemiology and Global Health
  8. Genomics and Evolutionary Biology
  9. Microbiology and Infectious Disease
  10. Neuroscience

(C) Curation of Scientific Findings

Scientists’ Dilemmas

(1) Confirming or disproving past studies

(2) Decades-long pursuit of a risky “moonshot”

(3) Trendy Topics with Editors 

 

@ PharmaceuticalIntelligence.com –  A Case Study on the LEADER in Curation of Scientific Findings

https://pharmaceuticalintelligence.com/2017/06/29/pharmaceuticalintelligence-com-a-case-study-on-the-leader-in-curation-of-scientific-findings/

Product Details

Cardiovascular Original Research: Cases in Methodology Design for Content Co-Curation: The Art of Scientific & Medical Curation

Nov 29, 2015 | Kindle eBook

by Larry H. Bernstein MD FCAP and Aviva Lev-Ari PhD RN
Subscribers read for free.
Auto-delivered wirelessly
Sold by: Amazon Digital Services LLC

 

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Reporter and Curator: Dr. Sudipta Saha, Ph.D.

 

Babies born at or before 25 weeks have quite low survival outcomes, and in the US it is the leading cause of infant mortality and morbidity. Just a few weeks of extra ‘growing time’ can be the difference between severe health problems and a relatively healthy baby.

 

Researchers from The Children’s Hospital of Philadelphia (USA) Research Institute have shown it’s possible to nurture and protect a mammal in late stages of gestation inside an artificial womb; technology which could become a lifesaver for many premature human babies in just a few years.

 

The researchers took eight lambs between 105 to 120 days gestation (the physiological equivalent of 23 to 24 weeks in humans) and placed them inside the artificial womb. The artificial womb is a sealed and sterile bag filled with an electrolyte solution which acts like amniotic fluid in the uterus. The lamb’s own heart pumps the blood through the umbilical cord into a gas exchange machine outside the bag.

 

The artificial womb worked in this study and after just four weeks the lambs’ brains and lungs had matured like normal. They had also grown wool and could wiggle, open their eyes, and swallow. Although this study is looking incredibly promising but getting the research up to scratch for human babies still requires a big leap.

 

Nevertheless, if all goes well, the researchers hope to test the device on premature humans within three to five years. Potential therapeutic applications of this invention may include treatment of fetal growth retardation related to placental insufficiency or the salvage of preterm infants threatening to deliver after fetal intervention or fetal surgery.

 

The technology may also provide the opportunity to deliver infants affected by congenital malformations of the heart, lung and diaphragm for early correction or therapy before the institution of gas ventilation. Numerous applications related to fetal pharmacologic, stem cell or gene therapy could be facilitated by removing the possibility for maternal exposure and enabling direct delivery of therapeutic agents to the isolated fetus.

 

References:

 

https://www.nature.com/articles/ncomms15112

 

 

https://www.sciencealert.com/researchers-have-successfully-grown-premature-lambs-in-an-artificial-womb

 

http://www.npr.org/sections/health-shots/2017/04/25/525044286/scientists-create-artificial-womb-that-could-help-prematurely-born-babies

 

http://www.telegraph.co.uk/science/2017/04/25/artificial-womb-promises-boost-survival-premature-babies/

 

https://www.theguardian.com/science/2017/apr/25/artificial-womb-for-premature-babies-successful-in-animal-trials-biobag

 

http://www.theblaze.com/news/2017/04/25/new-artificial-womb-technology-could-keep-babies-born-prematurely-alive-and-healthy/

 

http://www.theverge.com/2017/4/25/15421734/artificial-womb-fetus-biobag-uterus-lamb-sheep-birth-premie-preterm-infant

 

http://www.abc.net.au/news/2017-04-26/artificial-womb-could-one-day-keep-premature-babies-alive/8472960

 

https://www.theatlantic.com/health/archive/2017/04/preemies-floating-in-fluid-filled-bags/524181/

 

http://www.independent.co.uk/news/health/artificial-womb-save-premature-babies-lives-scientists-create-childrens-hospital-philadelphia-nature-a7701546.html

 

https://www.cnet.com/news/artificial-womb-births-premature-lambs-human-infants/

 

https://science.slashdot.org/story/17/04/25/2035243/an-artificial-womb-successfully-grew-baby-sheep—-and-humans-could-be-next

 

http://newatlas.com/artificial-womb-premature-babies/49207/

 

https://www.geneticliteracyproject.org/2015/06/12/artificial-wombs-the-coming-era-of-motherless-births/

 

http://news.nationalgeographic.com/2017/04/artificial-womb-lambs-premature-babies-health-science/

 

https://motherboard.vice.com/en_us/article/artificial-womb-free-births-just-got-a-lot-more-real-cambridge-embryo-reproduction

 

http://www.disclose.tv/news/The_Artificial_Womb_Is_Born_Welcome_To_The_WORLD_Of_The_MATRIX/114199

 

 

Read Full Post »


Protein profiling in cancer and metabolic diseases

Larry H. Bernstein, MD, FCAP, Curator

LPBI

 

Deep Protein Profiling Key

Company has encouraged by two recent reports that emphasise the importance of protein profiling to improve outcomes in cancer treatment.

http://www.technologynetworks.com/Proteomics/news.aspx?ID=190145

Proteome Sciences plc has strongly encouraged by two recent reports that emphasise the importance of protein profiling to improve outcomes in cancer treatment. These highlight the growing need for more detailed, personal assessment of protein profiles to improve the management of cancer treatment.

In the first study two groups from University College London and Cancer Research UK demonstrated that genetic mutations in cancer can lead to changes in the proteins on the cell surface1. These are new sequences which are seen as foreign by the body’s immune system and, with appropriate immunotherapy, the level of response in lung cancer was greatly enhanced.

However many of the patients with these types of mutations unfortunately still did not respond which highlighted the need for deeper analysis of the protein expression in tumours in order to better appreciate the mechanisms that contribute to treatment failure.

The second study, led by Professor Nigel Bundred of Manchester University, reported that use of two drugs that act on the same breast cancer target, an over-expressing protein called Her-2, were able to eradicate detectable tumours in around 10% of those treated in just 11 days, with 87% of those treated having a proteomic change indicating cells had stopped growing and/or cell death had increased2.

Whilst these results appear very promising it is worth noting that the over-expressing Her-2 target is only present in about 20% of breast tumours meaning this combination therapy was successful in clearing tumours in just 2% of the total breast cancer population.

Dr. Ian Pike, Chief Operating Officer of Proteome Sciences commented, “Both these recent studies should rightly be recognised as important steps forward towards better cancer treatment. However, in order to overcome the limitations of current drug therapy programs, a much deeper and more comprehensive analysis of the complex protein networks that regulate tumour growth and survival is required and will be essential to achieve a major advance in the battle to treat cancer.

“Our SysQuant® workflows provide that solution. As an example, in pancreatic cancer3 we have successfully mapped the complex network of regulatory processes and demonstrate the ability to devise personalised treatment combinations on an individual basis for each patient. A retrospective study with SysQuant® to predict response to the targeted drug Sorafenib in liver cancer is in process and we are planning further prospective trials to guide personalised treatment selection in liver cancer.

“We are already delivering systems-wide biology solutions through SysQuant® and TMTcalibrator™ programs to our clients that are generating novel biological data and results using more sensitive profiling that are helping them to better understand their drug development programs and to provide new biomarkers for tracking patient response in clinical trials.

“We are strongly positioned to deliver more comprehensive analysis of proteins and cellular pathways across other areas of disease and in particular to extend the use of SysQuant® with other leading cancer research groups in liver and other cancers.”

Proteome Sciences has also expanded its offering in personalised medicine through the use of its TMTcalibrator™ technology to uniquely identify protein biomarkers that reveal active cancer and other disease processes in body fluid samples. The importance of these ‘mechanistic’ biomarkers is that they are essential to monitor that drugs are being effective and that they can be used as early biomarkers of disease recurrence.

Using SysQuant® and TMTcalibrator™, Proteome Sciences can deliver more comprehensive analysis and provide unparalleled levels of sensitivity and breadth of coverage of the proteome, enabling faster, more efficient drug development and more accurate disease diagnosis.

 

Discovering ‘Outlier’ Enzymes

Researchers at TSRI and Salk Institute have discovered ‘Outlier’ enzymes that could offer new targets to treat type 2 diabetes and inflammatory disorders.

A team led by scientists at The Scripps Research Institute (TSRI) and the Salk Institute for Biological Studies have discovered two enzymes that appear to play a role in metabolism and inflammation—and might someday be targeted with drugs to treat type 2 diabetes and inflammatory disorders. The discovery is unusual because the enzymes do not bear a resemblance—in their structures or amino-acid sequences—to any known class of enzymes.

The team of scientists nevertheless identified them as “outlier” members of the serine/threonine hydrolase class, using newer techniques that detect biochemical activity. “A huge fraction of the human ‘proteome’ remains uncharacterized, and this paper shows how chemical approaches can be used to uncover proteins of a given functionality that have eluded classification based on sequence or predicted structure,” said co-senior author Benjamin F. Cravatt, chair of TSRI’s Department of Chemical Physiology.

“In this study, we found two genes that control levels of lipids with anti-diabetic and anti-inflammatory activity, suggesting exciting targets for diabetes and inflammatory diseases,” said co-senior author Alan Saghatelian, who holds the Dr. Frederik Paulsen Chair at the Salk Institute. The study, which appeared as a Nature Chemical Biology Advance Online Publication on March 28, 2016, began as an effort in the Cravatt laboratory to discover and characterize new serine/threonine hydrolases using fluorophosphonate (FP) probes—molecules that selectively bind and, in effect, label the active sites of these enzymes.

Pulling FP-binding proteins out of the entire proteome of test cells and identifying them using mass spectrometry techniques, the team matched nearly all to known hydrolases. The major outlier was a protein called androgen-induced gene 1 protein (AIG1). The only other one was a distant cousin in terms of sequence, a protein called ADTRP. “Neither of these proteins had been characterized as an enzyme; in fact, there had been little functional characterization of them at all,” said William H. Parsons, a research associate in the Cravatt laboratory who was co-first author of the study.

Experiments on AIG1 and ADTRP revealed that they do their enzymatic work in a unique way. “It looks like they have an active site that is novel—it had never been described in the literature,” said Parsons. Initial tests with panels of different enzyme inhibitors showed that AIG1 and ADTRP are moderately inhibited by inhibitors of lipases—enzymes that break down fats and other lipids. But on what specific lipids do these newly discovered outlier enzymes normally work?

At the Salk Institute, the Saghatelian laboratory was investigating a class of lipids it had discovered in 2014. Known as fatty acid esters of hydroxy fatty acids (FAHFAs), these molecules showed strong therapeutic potential. Saghatelian and his colleagues had found that boosting the levels of one key FAHFA lipid normalizes glucose levels in diabetic mice and also reduces inflammation.

“[Ben Cravatt’s] lab was screening panels of lipids to find the ones that their new enzymes work on,” said Saghatelian, who is a former research associate in the Cravatt laboratory. “We suggested they throw FAHFAs in there—and these turned out to be very good substrates.” The Cravatt laboratory soon developed powerful inhibitors of the newly discovered enzymes, and the two labs began working together, using the inhibitors and genetic techniques to explore the enzymes’ functions in vitro and in cultured cells.

Co-first author Matthew J. Kolar, an MD-PhD student, performed most of the experiments in the Saghatelian lab. The team concluded that AIG1 and ADTRP, at least in the cell types tested, appear to work mainly to break down FAHFAs and not any other major class of lipid. In principle, inhibitors of AIG1 and ADTRP could be developed into FAHFA-boosting therapies.

“Our prediction,” said Saghatelian, “is that if FAHFAs do what we think they’re doing, then using an enzyme inhibitor to block their degradation would make FAHFA levels go up and should thus reduce inflammation as well as improve glucose levels and insulin sensitivity.” The two labs are now collaborating on further studies of the new enzymes—and the potential benefits of inhibiting them—in mouse models of diabetes, inflammation and autoimmune disease.

“One of the neat things this study shows,” said Cravatt, “is that even for enzyme classes as well studied as the hydrolases, there may still be hidden members that, presumably by convergent evolution, arrived at that basic enzyme mechanism despite sharing no sequence or structural homology.”

Other co-authors of the study, “AIG1 and ADTRP are atypical integral membrane hydrolases that degrade bioactive FAHFAs,” were Siddhesh S. Kamat, Armand B. Cognetta III, Jonathan J. Hulce and Enrique Saez, of TSRI; and co-senior author Barbara B. Kahn of Beth Israel Deaconess Medical Center and Harvard Medical School

 

New Weapon Against Breast Cancer

Molecular marker in healthy tissue can predict a woman’s risk of getting the disease, research says.

Harvard Stem Cell Institute (HSCI) researchers at Dana-Farber Cancer Institute (DFCI) and collaborators at Brigham and Women’s Hospital (BWH) have identified a molecular marker in normal breast tissue that can predict a woman’s risk for developing breast cancer, the leading cause of death in women with cancer worldwide.

The work, led by HSCI principal faculty member Kornelia Polyak and Rulla Tamimi of BWH, was published in an early online release and in the April 1 issue of Cancer Research.

The study builds on Polyak’s earlier research finding that women already identified as having a high risk of developing cancer — namely those with a mutation called BRCA1 or BRCA2 — or women who did not give birth before their 30s had a higher number of mammary gland progenitor cells.

In the latest study, Polyak, Tamimi, and their colleagues examined biopsies, some taken as many as four decades ago, from 302 participants in the Nurses’ Health Study and the Nurses’ Health Study II who had been diagnosed with benign breast disease. The researchers compared tissue from the 69 women who later developed cancer to the tissue from the 233 women who did not. They found that women were five times as likely to develop cancer if they had a higher percentage of Ki67, a molecular marker that identifies proliferating cells, in the cells that line the mammary ducts and milk-producing lobules. These cells, called the mammary epithelium, undergo drastic changes throughout a woman’s life, and the majority of breast cancers originate in these tissues.

Doctors already test breast tumors for Ki67 levels, which can inform decisions about treatment, but this is the first time scientists have been able to link Ki67 to precancerous tissue and use it as a predictive tool.

“Instead of only telling women that they don’t have cancer, we could test the biopsies and tell women if they were at high risk or low risk for developing breast cancer in the future,” said Polyak, a breast cancer researcher at Dana-Farber and co-senior author of the paper.

“Currently, we are not able to do a very good job at distinguishing women at high and low risk of breast cancer,” added co-senior author Tamimi, an associate professor at the Harvard T.H. Chan School of Public Health and Harvard Medical School. “By identifying women at high risk of breast cancer, we can better develop individualized screening and also target risk reducing strategies.”

To date, mammograms are the best tool for the early detection, but there are risks associated with screening. False positive and negative results and over-diagnosis could cause psychological distress, delay treatment, or lead to overtreatment, according to the National Cancer Institute (NCI).

Mammography machines also use low doses of radiation. While a single mammogram is unlikely to cause harm, repeated screening can potentially cause cancer, though the NCI writes that the benefits “nearly always outweigh the risks.”

“If we can minimize unnecessary radiation for women at low risk, that would be good,” said Tamimi.

Screening for Ki67 levels would “be easy to apply in the current setting,” said Polyak, though the researchers first want to reproduce the results in an independent cohort of women.

 

AIG1 and ADTRP are atypical integral membrane hydrolases that degrade bioactive FAHFAs

William H ParsonsMatthew J Kolar, …., Barbara B KahnAlan Saghatelian & Benjamin F Cravatt

Nature Chemical Biology 28 March 2016                    http://dx.doi.org:/10.1038/nchembio.2051

Enzyme classes may contain outlier members that share mechanistic, but not sequence or structural, relatedness with more common representatives. The functional annotation of such exceptional proteins can be challenging. Here, we use activity-based profiling to discover that the poorly characterized multipass transmembrane proteins AIG1 and ADTRP are atypical hydrolytic enzymes that depend on conserved threonine and histidine residues for catalysis. Both AIG1 and ADTRP hydrolyze bioactive fatty acid esters of hydroxy fatty acids (FAHFAs) but not other major classes of lipids. We identify multiple cell-active, covalent inhibitors of AIG1 and show that these agents block FAHFA hydrolysis in mammalian cells. These results indicate that AIG1 and ADTRP are founding members of an evolutionarily conserved class of transmembrane threonine hydrolases involved in bioactive lipid metabolism. More generally, our findings demonstrate how chemical proteomics can excavate potential cases of convergent or parallel protein evolution that defy conventional sequence- and structure-based predictions.

Figure 1: Discovery and characterization of AIG1 and ADTRP as FP-reactive proteins in the human proteome.

 

http://www.nature.com/nchembio/journal/vaop/ncurrent/carousel/nchembio.2051-F1.jpg

(a) Competitive ABPP-SILAC analysis to identify FP-alkyne-inhibited proteins, in which protein enrichment and inhibition were measured in proteomic lysates from SKOV3 cells treated with FP-alkyne (20 μM, 1 h) or DMSO using the FP-biotin…

 

  1. Willems, L.I., Overkleeft, H.S. & van Kasteren, S.I. Current developments in activity-based protein profiling. Bioconjug. Chem. 25, 11811191 (2014).
  2. Niphakis, M.J. & Cravatt, B.F. Enzyme inhibitor discovery by activity-based protein profiling.Annu. Rev. Biochem. 83, 341377 (2014).
  3. Berger, A.B., Vitorino, P.M. & Bogyo, M. Activity-based protein profiling: applications to biomarker discovery, in vivo imaging and drug discovery. Am. J. Pharmacogenomics 4,371381 (2004).
  4. Liu, Y., Patricelli, M.P. & Cravatt, B.F. Activity-based protein profiling: the serine hydrolases.Proc. Natl. Acad. Sci. USA 96, 1469414699 (1999).
  5. Simon, G.M. & Cravatt, B.F. Activity-based proteomics of enzyme superfamilies: serine hydrolases as a case study. J. Biol. Chem. 285, 1105111055 (2010).
  6. Bachovchin, D.A. et al. Superfamily-wide portrait of serine hydrolase inhibition achieved by library-versus-library screening. Proc. Natl. Acad. Sci. USA 107, 2094120946 (2010).
  7. Jessani, N. et al. A streamlined platform for high-content functional proteomics of primary human specimens. Nat. Methods 2, 691697 (2005).
  8. Higa, H.H., Diaz, S. & Varki, A. Biochemical and genetic evidence for distinct membrane-bound and cytosolic sialic acid O-acetyl-esterases: serine-active-site enzymes. Biochem. Biophys. Res. Commun. 144, 10991108 (1987).

Academic cross-fertilization by public screening yields a remarkable class of protein phosphatase methylesteras-1 inhibitors

Proc Natl Acad Sci U S A. 2011 Apr 26; 108(17): 6811–6816.    doi:  10.1073/pnas.1015248108
National Institutes of Health (NIH)-sponsored screening centers provide academic researchers with a special opportunity to pursue small-molecule probes for protein targets that are outside the current interest of, or beyond the standard technologies employed by, the pharmaceutical industry. Here, we describe the outcome of an inhibitor screen for one such target, the enzyme protein phosphatase methylesterase-1 (PME-1), which regulates the methylesterification state of protein phosphatase 2A (PP2A) and is implicated in cancer and neurodegeneration. Inhibitors of PME-1 have not yet been described, which we attribute, at least in part, to a dearth of substrate assays compatible with high-throughput screening. We show that PME-1 is assayable by fluorescence polarization-activity-based protein profiling (fluopol-ABPP) and use this platform to screen the 300,000+ member NIH small-molecule library. This screen identified an unusual class of compounds, the aza-β-lactams (ABLs), as potent (IC50 values of approximately 10 nM), covalent PME-1 inhibitors. Interestingly, ABLs did not derive from a commercial vendor but rather an academic contribution to the public library. We show using competitive-ABPP that ABLs are exquisitely selective for PME-1 in living cells and mice, where enzyme inactivation leads to substantial reductions in demethylated PP2A. In summary, we have combined advanced synthetic and chemoproteomic methods to discover a class of ABL inhibitors that can be used to selectively perturb PME-1 activity in diverse biological systems. More generally, these results illustrate how public screening centers can serve as hubs to create spontaneous collaborative opportunities between synthetic chemistry and chemical biology labs interested in creating first-in-class pharmacological probes for challenging protein targets.

Protein phosphorylation is a pervasive and dynamic posttranslational protein modification in eukaryotic cells. In mammals, more than 500 protein kinases catalyze the phosphorylation of serine, threonine, and tyrosine residues on proteins (1). A much more limited number of phosphatases are responsible for reversing these phosphorylation events (2). For instance, protein phosphatase 2A (PP2A) and PP1 are thought to be responsible together for > 90% of the total serine/threonine phosphatase activity in mammalian cells (3). Specificity is imparted on PP2A activity by multiple mechanisms, including dynamic interactions between the catalytic subunit (C) and different protein-binding partners (B subunits), as well as a variety of posttranslational chemical modifications (2, 4). Within the latter category is an unusual methylesterification event found at the C terminus of the catalytic subunit of PP2A that is introduced and removed by a specific methyltransferase (leucine carbxoylmethyltransferase-1 or LCMT1) (5, 6) and methylesterase (protein phosphatase methylesterase-1 or PME-1) (7), respectively (Fig. 1A). PP2A carboxymethylation (hereafter referred to as “methylation”) has been proposed to regulate PP2A activity, at least in part, by modulating the binding interaction of the C subunit with various regulatory B subunits (810). A predicted outcome of these shifts in subunit association is the targeting of PP2A to different protein substrates in cells. PME-1 has also been hypothesized to stabilize inactive forms of nuclear PP2A (11), and recent structural studies have shed light on the physical interactions between PME-1 and the PP2A holoenzyme (12).

There were several keys to the success of our probe development effort. First, screening for inhibitors of PME-1 benefited from the fluopol-ABPP technology, which circumvented the limited throughput of previously described substrate assays for this enzyme. Second, we were fortunate that the NIH compound library contained several members of the ABL class of small molecules. These chiral compounds, which represent an academic contribution to the NIH library, occupy an unusual portion of structural space that is poorly accessed by commercial compound collections. Although at the time of their original synthesis (23) it may not have been possible to predict whether these ABLs would show specific biological activity, their incorporation into the NIH library provided a forum for screening against many proteins and cellular targets, culminating in their identification as PME-1 inhibitors. We then used advanced chemoproteomic assays to confirm the remarkable selectivity displayed by ABLs for PME-1 across (and beyond) the serine hydrolase superfamily. That the mechanism for PME-1 inhibition involves acylation of the enzyme’s conserved serine nucleophile (Fig. 3) suggests that exploration of a more structurally diverse set of ABLs might uncover inhibitors for other serine hydrolases. In this way, the chemical information gained from a single high-throughput screen may be leveraged to initiate probe development programs for additional enzyme targets.

Projecting forward, this research provides an example of how public small-molecule screening centers can serve as a portal for spawning academic collaborations between chemical biology and synthetic chemistry labs. By continuing to develop versatile high-throughput screens and combining them with a small-molecule library of expanding structural diversity conferred by advanced synthetic methodologies, academic biologists and chemists are well-positioned to collaboratively deliver pharmacological probes for a wide range of proteins and pathways in cell biology.

 

New weapon against breast cancer

Molecular marker in healthy tissue can predict a woman’s risk of getting the disease, research says

April 6, 2016 | Popular
BRC_Cancer605

 

New Group of Aging-Related Proteins Discovered

http://www.genengnews.com/gen-news-highlights/new-group-of-aging-related-proteins-discovered/81252599/

Scientists have discovered a group of six proteins that may help to divulge secrets of how we age, potentially unlocking new insights into diabetes, Alzheimer’s, cancer, and other aging-related diseases.

The proteins appear to play several roles in our bodies’ cells, from decreasing the amount of damaging free radicals and controlling the rate at which cells die to boosting metabolism and helping tissues throughout the body respond better to insulin. The naturally occurring amounts of each protein decrease with age, leading investigators to believe that they play an important role in the aging process and the onset of diseases linked to older age.

The research team led by Pinchas Cohen, M.D., dean and professor of the University of Southern California Leonard Davis School of Gerontology, identified the proteins and observed their origin from mitochondria and their game-changing roles in metabolism and cell survival. This latest finding builds upon prior research by Dr. Cohen and his team that uncovered two significant proteins, humanin and MOTS-c, hormones that appear to have significant roles in metabolism and diseases of aging.

Unlike most other proteins, humanin and MOTS-c are encoded in mitochondria. Dr. Cohen’s team used computer analysis to see if the part of the mitochondrial genome that provides the code for humanin was coding for other proteins as well. The analysis uncovered the genes for six new proteins, which were dubbed small humanin-like peptides, or SHLPs, 1 through 6 (pronounced “schlep”).

After identifying the six SHLPs and successfully developing antibodies to test for several of them, the team examined both mouse tissues and human cells to determine their abundance in different organs as well as their functions. The proteins were distributed quite differently among organs, which suggests that the proteins have varying functions based on where they are in the body. Of particular interest is SHLP 2, according to Dr. Cohen.  The protein appears to have insulin-sensitizing, antidiabetic effects as well as neuroprotective activity that may emerge as a strategy to combat Alzheimer’s disease. He added that SHLP 6 is also intriguing, with a unique ability to promote cancer cell death and thus potentially target malignant diseases.

Proteins That May Protect Against Age Related Illnesses Discovered

 

The cell proliferation antigen Ki-67 organises heterochromatin

 Michal Sobecki, 

Antigen Ki-67 is a nuclear protein expressed in proliferating mammalian cells. It is widely used in cancer histopathology but its functions remain unclear. Here, we show that Ki-67 controls heterochromatin organisation. Altering Ki-67 expression levels did not significantly affect cell proliferation in vivo. Ki-67 mutant mice developed normally and cells lacking Ki-67 proliferated efficiently. Conversely, upregulation of Ki-67 expression in differentiated tissues did not prevent cell cycle arrest. Ki-67 interactors included proteins involved in nucleolar processes and chromatin regulators. Ki-67 depletion disrupted nucleologenesis but did not inhibit pre-rRNA processing. In contrast, it altered gene expression. Ki-67 silencing also had wide-ranging effects on chromatin organisation, disrupting heterochromatin compaction and long-range genomic interactions. Trimethylation of histone H3K9 and H4K20 was relocalised within the nucleus. Finally, overexpression of human or Xenopus Ki-67 induced ectopic heterochromatin formation. Altogether, our results suggest that Ki-67 expression in proliferating cells spatially organises heterochromatin, thereby controlling gene expression.

 

A protein called Ki-67 is only produced in actively dividing cells, where it is located in the nucleus – the structure that contains most of the cell’s DNA. Researchers often use Ki-67 as a marker to identify which cells are actively dividing in tissue samples from cancer patients, and previous studies indicated that Ki-67 is needed for cells to divide. However, the exact role of this protein was not clear. Before cells can divide they need to make large amounts of new proteins using molecular machines called ribosomes and it has been suggested that Ki-67 helps to produce ribosomes.

Now, Sobecki et al. used genetic techniques to study the role of Ki-67 in mice. The experiments show that Ki-67 is not required for cells to divide in the laboratory or to make ribosomes. Instead, Ki-67 alters the way that DNA is packaged in the nucleus. Loss of Ki-67 from mice cells resulted in DNA becoming less compact, which in turn altered the activity of genes in those cells.

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Glycobiology advances

Larry H. Bernstein, MD, FCAP, Curator

LPBI

 

The Evolution of the Glycobiology Space

The Nascent Stage of another Omics Field with Biomarker and Therapeutic Potential

Enal Razvi, Ph.D. , Gary Oosta, Ph.D

http://www.genengnews.com/insight-and-intelligence/the-evolution-of-the-glycobiology-space/77900638/

 

The Evolution of the Glycobiology Space

 

Glycobiology is an important field of study with medical applications because it is known that tumor cells alter their glycosylation pattern, which may contribute to their metastatic potential as well as potential immune evasion. [iStock/© vjanez]    http://www.genengnews.com/media/images/AnalysisAndInsight/Apr12_2016_iStock_41612310_PlasmaMembraneOfACell1211657142.jpg

There is growing interest in the field of glycobiology given the fact that epitopes with physiological and pathological relevance have glyco moieties.  We believe that another “omics” revolution is on the horizon—the study of the glyco modifications on the surface of cells and their potential as biomarkers and therapeutic targets in many disease classes. Not much industry tracking of this field has taken place. Thus, we sought to map this landscape by examining the entire ensemble of academic publications in this space and teasing apart the trends operative in this field from a qualitative and quantitative perspective. We believe that this methodology of en masse capture and publication and annotation provides an effective approach to evaluate this early-stage field.

Identifiation and Growth of Glycobiology Publications

http://www.genengnews.com/Media/images/AnalysisAndInsight/thumb_April12_2016_SelectBiosciences_Figure11935315421.jpg

For this article, we identified 7000 publications in the broader glycobiology space and analyzed them in detail.  It is important to frame glycobiology in the context of genomics and proteomics as a means to assess the scale of the field. Figure 1 presents the relative sizes of these fields as assessed by publications in from 1975 to 2015.

Note that the relative scale of genomics versus proteomics and glycobiology/glycomics in this graph strongly suggests that glycobiology is a nascent space, and thus a driver for us to map its landscape today and as it evolves over the coming years.

Figure 2. (A) Segmentation of the glycobiology landscape. (B) Glycobiology versus glycomics publication growth.

 

http://www.genengnews.com/Media/images/AnalysisAndInsight/thumb_April12_2016_SelectBiosciences_Figure2ab1917013624.jpg

To examine closely the various components of the glycobiology space, we segmented the publications database, presented in Figure 2A. Note the relative sizes and growth rates (slopes) of the various segments.

Clearly, glycoconjugates currently are the majority of this space and account for the bulk of the publications.  Glycobiology and glycomics are small but expanding and therefore can be characterized as “nascent market segments.”  These two spaces are characterized in more detail in Figure 2B, which presents their publication growth rates.

Note the very recent increased attention directed at these spaces and hence our drive to initiate industry coverage of these spaces. Figure 2B presents the overall growth and timeline of expansion of these fields—especially glycobiology—but it provides no information about the qualitative nature of these fields.

Focus of Glycobiology Publications

http://www.genengnews.com/Media/images/AnalysisAndInsight/April12_2016_SelectBiosciences_Figure2c1827601892.jpg

Figure 2C. Word cloud based on titles of publications in the glycobiology and glycomics spaces.

To understand the focus of publications in this field, and indeed the nature of this field, we constructed a word cloud based on titles of the publications that comprise this space presented in Figure 2C.

There is a marked emphasis on terms such as oligosaccharides and an emphasis on cells (this is after all glycosylation on the surface of cells). Overall, a pictorial representation of the types and classes of modifications that comprise this field emerge in this word cloud, demonstrating the expansion of the glycobiology and to a lesser extent the glycomics spaces as well as the character of these nascent but expanding spaces.

Characterization of the Glycobiology Space in Journals

Figure 3A. Breakout of publications in the glycobiology/glycomics fields.   http://www.genengnews.com/Media/images/AnalysisAndInsight/April12_2016_SelectBiosciences_Figure3a_5002432117316.jpg
Having framed the overall growth of the glycobiology field, we wanted to understand its structure and the classes of researchers as well as publications that comprise this field. To do this, we segmented the publications that constitute this field into the various journals in which glycobiology research is published. Figure 3A presents the breakout of publications by journal to illustrate the “scope” of this field.

The distribution of glycobiology publications across the various journals suggests a very concentrated marketplace that is very technically focused. The majority of the publications segregate into specialized journals on this topic, a pattern very indicative of a field in the very early stages of development—a truly nascent marketplace.

http://www.genengnews.com/Media/images/AnalysisAndInsight/thumb_April12_2016_SelectBiosciences_Figure3b1012091061.jpg

Figure 3B. Origin of publications in the glycobiology/glycomics fields.
We also sought to understand the “origin” of these publications—the breakout between academic- versus industry-derived journals. Figure 3B presents this breakout and shows that these publications are overwhelmingly (92.3%) derived from the academic sector. This is again a testimonial to the early nascent nature of this marketplace without significant engagement by the commercial sector and therefore is an important field to characterize and track from the ground up.

Select Biosciences, Inc. further analyzed the growth trajectory of the glycobiology papers in Figure 3C as a means to examine closely the publications trajectory. Although there appears to be some wobble along the way, overall the trajectory is upward, and of late it is expanding significantly.

In Summary

Figure 3C. Trajectory of the glycobiology space.   http://www.genengnews.com/Media/images/AnalysisAndInsight/April12_2016_SelectBiosciences_Figure3c1236921793.jpg
Glycobiology is the study of what coats living cells—glycans, or carbohydrates, and glycoconjugates. This is an important field of study with medical applications because it is known that tumor cells alter their glycosylation pattern, which may contribute to their metastatic potential as well as potential immune evasion.

At this point, glycobiology is largely basic research and thus it pales in comparison with the field of genomics. But in 10 years, we predict the study of glycobiology and glycomics will be ubiquitous and in the mainstream.

We started our analysis of this space because we’ve been focusing on many other classes of analytes, such as microRNAs, long-coding RNAs, oncogenes, tumor suppressor genes, etc., whose potential as biomarkers is becoming established. Glycobiology, on the other hand, represents an entire new space—a whole new category of modifications that could be analyzed for diagnostic potential and perhaps also for therapeutic targeting.

Today, glycobiology and glycomics are where genomics was at the start of the Human Genome Project. They respresent a nascent space and with full headroom for growth. Select Biosciences will continue to track this exciting field for research developments as well as development of biomarkers based on glyco-epitopes.

Enal Razvi, Ph.D., conducted his doctoral work on viral immunology and subsequent to receiving his Ph.D. went on to the Rockefeller University in New York to serve as Aaron Diamond Post-doctoral fellow under Professor Ralph Steinman [Nobel Prize Winner in 2011 for his discovery of dendritic cells in the early-70s with Zanvil Cohn]. Subsequently, Dr. Razvi completed his research fellowship at Harvard Medical School. For the last two decades Dr. Razvi has worked with small and large companies and consulted for more than 100 clients worldwide. He currently serves as Biotechnology Analyst and Managing Director of SelectBio U.S. He can be reached at enal@selectbio.us. Gary M. Oosta holds a Ph.D. in Biophysics from Massachusetts Institute of Technology and a B.A. in Chemistry from E. Mich. Univ. He has 25 years of industrial research experience in various technology areas including medical diagnostics, thin-layer coating, bio-effects of electromagnetic radiation, and blood coagulation. Dr. Oosta has authored 20 technical publications and is an inventor on 77 patents worldwide. In addition, he has managed research groups that were responsible for many other patented innovations. Dr. Oosta has a long-standing interest in using patents and publications as strategic technology indicators for future technology selection and new product development. To enjoy more articles like this from GEN, click here to subscribe now!

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High blood pressure can damage the retina’s blood vessels and limit the retina’s function. It can also put pressure on the optic nerve.

Sourced through Scoop.it from: www.healthline.com

See on Scoop.itCardiovascular Disease: PHARMACO-THERAPY

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Einstein and General Theory of Relativity

Larry H. Bernstein, MD, FCAP, Curator

LPBI

 

 

General Relativity And The ‘Lone Genius’ Model Of Science

Chad Orzel

http://www.forbes.com/sites/chadorzel/2015/11/24/general-relativity-and-the-lone-genius-model-of-science/

 

(Credit: AP)

 

One hundred years ago this Wednesday, Albert Einstein gave the last of a series of presentations to the Prussian Academy of Sciences, which marks the official completion of his General Theory of Relativity. This anniversary is generating a good deal of press and various celebratory events, such as the premiere of a new documentary special. If you prefer your physics explanations in the plainest language possible, there’s even an “Up Goer Five” version (personally, I don’t find these all that illuminating, but lots of people seem to love it).

Einstein is, of course, the most iconic scientist in history, and much of the attention to this week’s centennial will center on the idea of his singular genius. Honestly, general relativity is esoteric enough that were it not for Einstein’s personal fame, there probably wouldn’t be all that much attention paid to this outside of the specialist science audience.

But, of course, while the notion of Einstein as a lone, unrecognized genius is a big part of his myth, he didn’t create relativity entirely on his own, asthis article in Nature News makes clear. The genesis of relativity is a single simple idea, but even in the early stages, when he developed Special Relativity while working as a patent clerk, he honed his ideas through frequent discussions with friends and colleagues. Most notable among these was probably Michele Besso, who Einstein later referred to as “the best sounding board in Europe.”

And most of the work on General Relativity came not when Einstein was toiling in obscurity, but after he had begun to climb the academic ladder in Europe. In the ten years between the Special and General theories, he went through a series of faculty jobs of increasing prestige. He also laboriously learned a great deal of mathematics in order to reach the final form of the theory, largely with the assistance of his friend Marcel Grossmann. The path to General Relativity was neither simple nor solitary, and the Nature piece documents both the mis-steps along the way and the various people who helped out.

While Einstein wasn’t working alone, though, the Nature piece also makes an indirect case for his status as a genius worth celebrating. Not because of the way he solved the problem, but through the choice of problem to solve. Einstein pursued a theory that would incorporate gravitation into relativity with dogged determination through those years, but he was one of a very few people working on it. There were a couple of other theories kicking around, particularly Gunnar Nordström’s, but these didn’t generate all that much attention. The mathematician David Hilbert nearly scooped Einstein with the final form of the field equations in November of 1915 (some say he did get there first), but Hilbert was a latecomer who only got interested in the problem of gravitation after hearing about it from Einstein, and his success was a matter of greater familiarity with the necessary math. One of the books I used when I taught a relativity class last year quoted Hilbert as saying that “every child in the streets of Göttingen knows more about four-dimensional geometry than Einstein,” but that Einstein’s physical insight got him to the theory before superior mathematicians.

 

History: Einstein was no lone genius

Michel Janssen & Jürgen Renn   

16 November 2015 Corrected:   17 November 2015    Nature Nov 2015; 527(7578)

Lesser-known and junior colleagues helped the great physicist to piece together his general theory of relativity, explain Michel Janssen and Jürgen Renn.

http://www.nature.com/news/history-einstein-was-no-lone-genius-1.18793

 

http://www.nature.com/polopoly_fs/7.31357.1447429421!/image/Comment2.jpg_gen/derivatives/landscape_630/Comment2.jpg

Marcel Grossmann (left) and Michele Besso (right), university friends of Albert Einstein (centre), both made important contributions to general relativity.

 

A century ago, in November 1915, Albert Einstein published his general theory of relativity in four short papers in the proceedings of the Prussian Academy of Sciences in Berlin1. The landmark theory is often presented as the work of a lone genius. In fact, the physicist received a great deal of help from friends and colleagues, most of whom never rose to prominence and have been forgotten2, 3, 4, 5. (For full reference details of all Einstein texts mentioned in this piece, seeSupplementary Information.)

Here we tell the story of how their insights were woven into the final version of the theory. Two friends from Einstein’s student days — Marcel Grossmann and Michele Besso — were particularly important. Grossmann was a gifted mathematician and organized student who helped the more visionary and fanciful Einstein at crucial moments. Besso was an engineer, imaginative and somewhat disorganized, and a caring and lifelong friend to Einstein. A cast of others contributed too.

Einstein met Grossmann and Besso at the Swiss Federal Polytechnical School in Zurich6 — later renamed the Swiss Federal Institute of Technology (Eidgenössische Technische Hochschule; ETH) — where, between 1896 and 1900, he studied to become a school teacher in physics and mathematics. Einstein also met his future wife at the ETH, classmate Mileva Marić. Legend has it that Einstein often skipped class and relied on Grossmann’s notes to pass exams.

 

http://www.nature.com/polopoly_fs/7.31485.1447758022!/image/entanglement.jpg_gen/derivatives/fullsize/entanglement.jpg

 

Grossmann’s father helped Einstein to secure a position at the patent office in Berne in 1902, where Besso joined him two years later. Discussions between Besso and Einstein earned the former the sole acknowledgment in the most famous of Einstein’s 1905 papers, the one introducing the special theory of relativity. As well as publishing the papers that made 1905 his annus mirabilis, Einstein completed his dissertation that year to earn a PhD in physics from the University of Zurich.

In 1907, while still at the patent office, he started to think about extending the principle of relativity from uniform to arbitrary motion through a new theory of gravity. Presciently, Einstein wrote to his friend Conrad Habicht — whom he knew from a reading group in Berne mockingly called the Olympia Academy by its three members — saying that he hoped that this new theory would account for a discrepancy of about 43˝ (seconds of arc) per century between Newtonian predictions and observations of the motion of Mercury’s perihelion, the point of its orbit closest to the Sun.

Einstein started to work in earnest on this new theory only after he left the patent office in 1909, to take up professorships first at the University of Zurich and two years later at the Charles University in Prague. He realized that gravity must be incorporated into the structure of space-time, such that a particle subject to no other force would follow the straightest possible trajectory through a curved space-time.

In 1912, Einstein returned to Zurich and was reunited with Grossmann at the ETH. The pair joined forces to generate a fully fledged theory. The relevant mathematics was Gauss’s theory of curved surfaces, which Einstein probably learned from Grossmann’s notes. As we know from recollected conversations, Einstein told Grossmann7: “You must help me, or else I’ll go crazy.”

Their collaboration, recorded in Einstein’s ‘Zurich notebook‘, resulted in a joint paper published in June 1913, known as the Entwurf (‘outline’) paper. The main advance between this 1913 Entwurf theory and the general relativity theory of November 1915 are the field equations, which determine how matter curves space-time. The final field equations are ‘generally covariant’: they retain their form no matter what system of coordinates is chosen to express them. The covariance of the Entwurf field equations, by contrast, was severely limited.

 

http://www.nature.com/polopoly_fs/7.31488.1447759403!/image/einstein_lost.jpg_gen/derivatives/fullsize/einstein_lost.jpg

Einstein’s lost theory uncovered

 

Two Theories

In May 1913, as he and Grossmann put the finishing touches to their Entwurf paper, Einstein was asked to lecture at the annual meeting of the Society of German Natural Scientists and Physicians to be held that September in Vienna, an invitation that reflects the high esteem in which the 34-year-old was held by his peers.

In July 1913, Max Planck and Walther Nernst, two leading physicists from Berlin, came to Zurich to offer Einstein a well-paid and teaching-free position at the Prussian Academy of Sciences in Berlin, which he swiftly accepted and took up in March 1914. Gravity was not a pressing problem for Planck and Nernst; they were mainly interested in what Einstein could do for quantum physics.  (It was Walther Nernst who advised that Germany could not engage in WWI and win unless it was a short war).

Several new theories had been proposed in which gravity, like electromagnetism, was represented by a field in the flat space-time of special relativity. A particularly promising one came from the young Finnish physicist Gunnar Nordström. In his Vienna lecture, Einstein compared his own Entwurf theory to Nordström’s theory. Einstein worked on both theories between May and late August 1913, when he submitted the text of his lecture for publication in the proceedings of the 1913 Vienna meeting.

In the summer of 1913, Nordström visited Einstein in Zurich. Einstein convinced him that the source of the gravitational field in both their theories should be constructed out of the ‘energy–momentum tensor’: in pre-relativistic theories, the density and the flow of energy and momentum were represented by separate quantities; in relativity theory, they are combined into one quantity with ten different components.

 

http://www.nature.com/polopoly_fs/7.31358.1447420168!/image/Comment4.jpg_gen/derivatives/landscape_630/Comment4.jpg

ETH-Bibliothek Zürich, Bildarchiv

ETH Zurich, where Einstein met friends with whom he worked on general relativity.

 

This energy–momentum tensor made its first appearance in 1907–8 in the special-relativistic reformulation of the theory of electrodynamics of James Clerk Maxwell and Hendrik Antoon Lorentz by Hermann Minkowski. It soon became clear that an energy–momentum tensor could be defined for physical systems other than electromagnetic fields. The tensor took centre stage in the new relativistic mechanics presented in the first textbook on special relativity, Das Relativitätsprinzip, written by Max Laue in 1911. In 1912, a young Viennese physicist, Friedrich Kottler, generalized Laue’s formalism from flat to curved space-time. Einstein and Grossmann relied on this generalization in their formulation of the Entwurf theory. During his Vienna lecture, Einstein called for Kottler to stand up and be recognized for this work8.

Einstein also worked with Besso that summer to investigate whether the Entwurf theory could account for the missing 43˝ per century for Mercury’s perihelion. Unfortunately, they found that it could only explain 18˝. Nordström’s theory, Besso checked later, gave 7˝ in the wrong direction. These calculations are preserved in the ‘Einstein–Besso manuscript‘ of 1913.

Besso contributed significantly to the calculations and raised interesting questions. He wondered, for instance, whether the Entwurf field equations have an unambiguous solution that uniquely determines the gravitational field of the Sun. Historical analysis of extant manuscripts suggests that this query gave Einstein the idea for an argument that reconciled him with the restricted covariance of the Entwurf equations. This ‘hole argument’ seemed to show that generally covariant field equations cannot uniquely determine the gravitational field and are therefore inadmissible9.

Einstein and Besso also checked whether the Entwurf equations hold in a rotating coordinate system. In that case the inertial forces of rotation, such as the centrifugal force we experience on a merry-go-round, can be interpreted as gravitational forces. The theory seemed to pass this test. In August 1913, however, Besso warned him that it did not. Einstein did not heed the warning, which would come back to haunt him.

 

http://www.nature.com/polopoly_fs/7.31486.1447758069!/image/integrity.jpg_gen/derivatives/fullsize/integrity.jpg

Scientific method: Defend the integrity of physics

 

In his lecture in Vienna in September 1913, Einstein concluded his comparison of the two theories with a call for experiment to decide. The Entwurf theory predicts that gravity bends light, whereas Nordström’s does not. It would take another five years to find out. Erwin Finlay Freundlich, a junior astronomer in Berlin with whom Einstein had been in touch since his days in Prague, travelled to Crimea for the solar eclipse of August 1914 to determine whether gravity bends light but was interned by the Russians just as the First World War broke out. Finally, in 1919, English astronomer Arthur Eddington confirmed Einstein’s prediction of light bending by observing the deflection of distant stars seen close to the Sun’s edge during another eclipse, making Einstein a household name10.

Back in Zurich, after the Vienna lecture, Einstein teamed up with another young physicist, Adriaan Fokker, a student of Lorentz, to reformulate the Nordström theory using the same kind of mathematics that he and Grossmann had used to formulate the Entwurf theory. Einstein and Fokker showed that in both theories the gravitational field can be incorporated into the structure of a curved space-time. This work also gave Einstein a clearer picture of the structure of the Entwurf theory, which helped him and Grossmann in a second joint paper on the theory. By the time it was published in May 1914, Einstein had left for Berlin.

 

http://www.nature.com/polopoly_fs/7.31489.1447761264!/image/Einstein_frontal_small.jpg_gen/derivatives/fullsize/Einstein_frontal_small.jpg

Snapshots explore Einstein’s unusual brain

 

The Breakup

Turmoil erupted soon after the move. Einstein’s marriage fell apart and Mileva moved back to Zurich with their two young sons. Albert renewed the affair he had started and broken off two years before with his cousin Elsa Löwenthal (née Einstein). The First World War began. Berlin’s scientific elite showed no interest in the Entwurf theory, although renowned colleagues elsewhere did, such as Lorentz and Paul Ehrenfest in Leiden, the Netherlands. Einstein soldiered on.

By the end of 1914, his confidence had grown enough to write a long exposition of the theory. But in the summer of 1915, after a series of his lectures in Göttingen had piqued the interest of the great mathematician David Hilbert, Einstein started to have serious doubts. He discovered to his dismay that the Entwurf theory does not make rotational motion relative. Besso was right. Einstein wrote to Freundlich for help: his “mind was in a deep rut”, so he hoped that the young astronomer as “a fellow human being with unspoiled brain matter” could tell him what he was doing wrong. Freundlich could not help him.

“Worried that Hilbert might beat him to the punch, Einstein rushed new equations into print.”

The problem, Einstein soon realized, lay with the Entwurf field equations. Worried that Hilbert might beat him to the punch, Einstein rushed new equations into print in early November 1915, modifying them the following week and again two weeks later in subsequent papers submitted to the Prussian Academy. The field equations were generally covariant at last.

In the first November paper, Einstein wrote that the theory was “a real triumph” of the mathematics of Carl Friedrich Gauss and Bernhard Riemann. He recalled in this paper that he and Grossmann had considered the same equations before, and suggested that if only they had allowed themselves to be guided by pure mathematics rather than physics, they would never have accepted equations of limited covariance in the first place.

Other passages in the first November paper, however, as well as his other papers and correspondence in 1913–15, tell a different story. It was thanks to the elaboration of the Entwurf theory, with the help of Grossmann, Besso, Nordström and Fokker, that Einstein saw how to solve the problems with the physical interpretation of these equations that had previously defeated him.

In setting out the generally covariant field equations in the second and fourth papers, he made no mention of the hole argument. Only when Besso and Ehrenfest pressed him a few weeks after the final paper, dated 25 November, did Einstein find a way out of this bind — by realizing that only coincident events and not coordinates have physical meaning. Besso had suggested a similar escape two years earlier, which Einstein had brusquely rejected2.

In his third November paper, Einstein returned to the perihelion motion of Mercury. Inserting the astronomical data supplied by Freundlich into the formula he derived using his new theory, Einstein arrived at the result of 43″ per century and could thus fully account for the difference between Newtonian theory and observation. “Congratulations on conquering the perihelion motion,” Hilbert wrote to him on 19 November. “If I could calculate as fast as you can,” he quipped, “the hydrogen atom would have to bring a note from home to be excused for not radiating.”

Einstein kept quiet on why he had been able to do the calculations so fast. They were minor variations on the ones he had done with Besso in 1913. He probably enjoyed giving Hilbert a taste of his own medicine: in a letter to Ehrenfest written in May 1916, Einstein characterized Hilbert’s style as “creating the impression of being superhuman by obfuscating one’s methods”.

Einstein emphasized that his general theory of relativity built on the work of Gauss and Riemann, giants of the mathematical world. But it also built on the work of towering figures in physics, such as Maxwell and Lorentz, and on the work of researchers of lesser stature, notably Grossmann, Besso, Freundlich, Kottler, Nordström and Fokker. As with many other major breakthroughs in the history of science, Einstein was standing on the shoulders of many scientists, not just the proverbial giants4.

 

http://www.nature.com/polopoly_fs/7.31375.1447420557!/image/cartoon.jpg_gen/derivatives/landscape_630/cartoon.jpg

Berlin’s physics elite (Fritz Haber, Walther Nernst, Heinrich Rubens, Max Planck) and Einstein’s old and new family (Mileva Einstein-Marić and heir sons Eduard and Hans Albert; Elsa Einstein-Löwenthal and her daughters Ilse and Margot) are watching as Einstein is pursuing his new theory of gravity and his idée fixeof generalizing the relativity principle while carried by giants of both physics and mathematics (Isaac Newton, James Clerk Maxwell, Carl Friedrich Gauss, Bernhard Riemann) and scientists of lesser stature (Marcel Grossmann, Gunnar Nordström, Erwin Finlay Freundlich, Michele Besso).

Nature 527, 298–300 (19 Nov 2015)       http://dx.doi.org:/10.1038/527298a

 

 

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Twitter, Google, LinkedIn Enter in the Curation Foray: What’s Up With That?

 

Reporter: Stephen J. Williams, Ph.D.

Recently Twitter has announced a new feature which they hope to use to increase engagement on their platform. Originally dubbed Project Lightning and now called Moments, this feature involves many human curators which aggregate and curate tweets surrounding individual live events(which used to be under #Live).

As Madhu Muthukumar (@justmadhu), Twitter’s Product Manager, published a blog post describing Moments said:

“Every day, people share hundreds of millions of tweets. Among them are things you can’t experience anywhere but on Twitter: conversations between world leaders and celebrities, citizens reporting events as they happen, cultural memes, live commentary on the night’s big game, and many more,” the blog post noted. “We know finding these only-on-Twitter moments can be a challenge, especially if you haven’t followed certain accounts. But it doesn’t have to be.”

Please see more about Moments on his blog here.

Moments is a new tab on Twitter’s mobile and desktop home screens where the company will curate trending topics as they’re unfolding in real-time — from citizen-reported news to cultural memes to sports events and more. Moments will fall into five total categories, including “Today,” “News,” “Sports,” “Entertainment” and “Fun.” (Source: Fox)

Now It’s Google’s Turn

 

As Dana Blankenhorn wrote in his article Twitter, Google Try It Buzzfeed’s Way With Curation

in SeekingAlpha

What’s a challenge for Google is a direct threat to Twitter’s existence.

For all the talk about what doesn’t work in journalism, curation works. Following the news, collecting it and commenting, and encouraging discussion, is the “secret sauce” for companies like Buzzfeed, Vox, Vice and The Huffington Post, which often wind up getting more traffic from a story at, say The New York Times (NYSE:NYT), than the Times does as a result.

Curation is, in some ways, a throwback to the pre-Internet era. It’s done by people. (At least I think I’m a people.) So as odd as it is for Twitter (NYSE:TWTR) to announce it will curate live events it’s even odder to see Google (NASDAQ:GOOG) (NASDAQ:GOOGL) doing it in a project called YouTube Newswire.

Buzzfeed, Google’s content curation platform, made for desktop as well as a mobile app, allows sharing of curated news, viral videos.

The feel for both Twitter and Google’s content curation will be like a newspaper, with an army of human content curators determining what is the trendiest news to read or videos to watch.

BuzzFeed articles, or at least, the headlines can easily be mined from any social network but reading the whole article still requires that you open the link within the app or outside using a mobile web browser. Loading takes some time–a few seconds longer. Try browsing the BuzzFeed feed on the app and you’ll notice the obvious difference.

However it was earlier this summer in a Forbes article Why Apple, Snapchat and Twitter are betting on human editors, but Facebook and Google aren’t that Apple, Snapchat and Twitter as well as LinkedIn Pulse and Instragram were going to use human editors and curators while Facebook and Google were going to rely on their powerful algorithms. Google (now Alphabet) CEO Eric Schmidt has even called Apple’s human curated playlists “elitist” although Google Play has human curated playlists.

Maybe Google is responding to views on its Google News like this review in VentureBeat:

Google News: Less focused on social signals than textual ones, Google News uses its analytic tools to group together related stories and highlight the biggest ones. Unlike Techmeme, it’s entirely driven by algorithms, and that means it often makes weird choices. I’ve heard that Google uses social sharing signals from Google+ to help determine which stories appear on Google News, but have never heard definitive confirmation of that — and now that Google+ is all but dead, it’s mostly moot. I find Google News an unsatisfying home page, but it is a good place to search for news once you’ve found it.

Now WordPress Too!

 

WordPress also has announced its curation plugin called Curation Traffic.

According to WordPress

You Own the Platform, You Benefit from the Traffic

“The Curation Traffic™ System is a complete WordPress based content curation solution. Giving you all the tools and strategies you need to put content curation into action.

It is push-button simple and seamlessly integrates with any WordPress site or blog.

With Curation Traffic™, curating your first post is as easy as clicking “Curate” and the same post that may originally only been sent to Facebook or Twitter is now sent to your own site that you control, you benefit from, and still goes across all of your social sites.”

The theory the more you share on your platform the more engagement the better marketing experience. And with all the WordPress users out there they have already an army of human curators.

So That’s Great For News But What About Science and Medicine?

 

The news and trendy topics such as fashion and music are common in most people’s experiences. However more technical areas of science, medicine, engineering are not in most people’s domain so aggregation of content needs a process of peer review to sort basically “the fact from fiction”. On social media this is extremely important as sensational stories of breakthroughs can spread virally without proper vetting and even influence patient decisions about their own personal care.

Expertise Depends on Experience

In steps the human experience. On this site (www.pharmaceuticalintelligence.com) we attempt to do just this. A consortium of M.D.s, Ph.D. and other medical professionals spend their own time to aggregate not only topics of interest but curate on specific topics to add some more insight from acceptable sources over the web.

In Power of Analogy: Curation in Music, Music Critique as a Curation and Curation of Medical Research Findings – A Comparison; Dr. Larry Berstein compares a museum or music curator to curation of scientific findings and literature and draws similar conclusions from each: that a curation can be a tool to gain new insights previously unseen an observer. A way of stepping back to see a different picture, hear a different song.

 

For instance, using a Twitter platform, we curate #live meeting notes and tweets from meeting attendees (please see links below and links within) to give a live conference coverage

https://pharmaceuticalintelligence.com/press-coverage/

and curation and analysis give rise not only to meeting engagement butunique insights into presentations.

 

In addition, the use of a WordPress platform allows easy sharing among many different social platforms including Twitter, Google+, LinkedIn, Pinterest etc.

Hopefully, this will catch on to the big powers of Twitter, Google and Facebook to realize there exists armies of niche curation communities which they can draw on for expert curation in the biosciences.

Other posts on this site on Curation and include

 

Inevitability of Curation: Scientific Publishing moves to embrace Open Data, Libraries and Researchers are trying to keep up

The Methodology of Curation for Scientific Research Findings

Scientific Curation Fostering Expert Networks and Open Innovation: Lessons from Clive Thompson and others

The growing importance of content curation

Data Curation is for Big Data what Data Integration is for Small Data

Stem Cells and Cardiac Repair: Content Curation & Scientific Reporting

Cardiovascular Diseases and Pharmacological Therapy: Curations

Power of Analogy: Curation in Music, Music Critique as a Curation and Curation of Medical Research Findings – A Comparison

 

 

 

 

 

 

 

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Mature cells can be reprogrammed to become pluripotent – John Gurdon and Shinya Yamanaka

Larry H. Bernstein, MD, FCAP, Curator

Leaders in Pharmaceutical Innovation

Series E: 2; 7.1

In 1962, John B. Gurdon successfully cloned frogs. He took the nucleus of an adult frog cell – the part of the cell that holds the DNA – and put it into a frog egg cell. The egg was able to develop into a normal tadpole. These experiments showed that an adult, specialised cell still had the information needed to form a new tadpole. The same technique was later used to produce the famous cloned sheep, Dolly.

In 2006, Shinya Yamanaka’s work again took the scientific community by surprise and changed the way researchers think about how cells develop.Yamanaka showed that adult, fully specialised mouse cells could be reprogrammed to become cells that behave like embryonic stem cells – so-called induced pluripotent stem cells, which can develop into all types of cells in the body.

Gurdon and Yamanaka’s work is celebrated and explained in the award-winning documentary, Stem Cell Revolutions, by Clare Blackburn and Amy Hardie. The short clip above is taken from the film and links Gurdon and Yamanaka’s work (click the red button on the image above to watch the clip). Amy Hardie, who directed the film, commented: “So many scientists have said that Shinya Yamanaka has overturned our understanding of basic developmental biology. And he has – with the discovery of iPS cells. What Shinya Yamanaka himself points out and we were able to show in our film, Stem Cell Revolutions, is the lineage from John Gurdon who cloned frogs in Cambridge. Shinya’s groundbreaking discovery would not have been possible without Gurdon’s pioneering work.

Proc Natl Acad Sci U S A. 2013 Apr 9; 110(15): 5740–5741.

Published online 2013 Mar 28. doi:  10.1073/pnas.1221823110

Sir John Bertrand Gurdon, FRS, FMedSci (born 2 October 1933), is an English developmental biologist. He is best known for his pioneering research in nuclear transplantation[2][3][4] and cloning.[1][5][6][7] He was awarded the Lasker Award in 2009. In 2012, he and Shinya Yamanaka were awarded the Nobel Prize for Physiology or Medicine for the discovery that mature cells can be converted to stem cells.[8]

The Nobel Prize in Physiology or Medicine 2012
Sir John B. Gurdon, Shinya Yamanaka

ohn Bertrand Gurdon (JBG), born 2 October 1933, was brought up in a comfortable home by his parents (fig.1) on the Surrey/Hampshire border in a village, Frensham in South England, endowed with a large amount of National Trust heathland and ponds. His mother, Marjorie Byass, was from an East Yorkshire farming family. Brought up on a farm, and educated in that region, she became a physical training teacher working for some time in an American private school. When her son and daughter (Caroline, who trained as a nurse) had been raised, she gave much time to the regional administration of the “Women’s Institute,” a voluntary organisation for educating women.

His father, William Gurdon, was from a longstanding Suffolk family whose ancestors go back to 1199 (fig. 2; Muskett, 1900; Cunnington, 2008); with the family motto “virtus viget in arduis” [virtue flourishes in adversity].

Paternal lineage of JBG.

Many of them had distinguished careers in government and as regional administrators, including Sir Adam Gurdon [Muskett, 1900]. JBG’s ancestors lived in a stately home, Assington Hall, in West Suffolk (fig. 3).

His grandfather had to leave the family home through lack of money to maintain it, due to repeal of the Corn Laws (1846) so that tenant farmers could no longer pay their rent, because of foreign imports. Assington Hall was requisitioned by the army during World War II, and was burnt down in a supposedly accidental fire in 1957. The remaining part of the house was partly restored and part of the original home, including its minarets, is still present in Assington. One of JBG’s ancestors married again after his first wife died and the outcome of a second marriage yielded a distinguished lawyer who accepted the hereditary title of Baron Cranworth. JBG’s father left school at the age of 16 and took a position in a rice broking firm in Burma. He was an early volunteer in the First World War and was decorated with the Distinguished Conduct Medal (DCM) before being commissioned to an officer rank. After that he led a career in banking in Assam and East India. He retired, in his forties, and in retirement, he gave much time to the transcribing of professional textbooks (especially legal) into Braille for the blind as voluntary work.

World War II started in 1939 when JBG was aged six. It was a time of austerity. Limited rations of food were managed by his mother, and the garden was used to raise chickens. He did not see luxuries like a banana or an orange until well after the end of the war. At the age of eight he was sent to a local private school, Frensham Heights. In an intelligence test at that age, he was asked to draw an orange. He started drawing the stalk by which the orange would hang from a tree, reasoning that an orange would not exist in space. The teacher tore up the piece of paper and reported to his parents that he was mentally subnormal and would need special teaching. The teacher meant to say, draw a circle. He was moved to another private school in the village, namely Edgeborough, where he thrived. At that age he had an intense interest in plants and insects. In most of his spare time he collected butterflies and moths and raised their caterpillars.

At the age of 13, he started school at Eton as a boarder. He found life there intensely uncomfortable, because senior boys acted as despots, administering punishments for trivial misdemeanours. As a means of survival, he took up squash, and as a result of hard work rather than ability, he became eventually the school captain in this sport. While at school he continued his interest in Lepidoptera, raising large numbers of moths from their larval stage.

Gurdon attended Edgeborough and then Eton College, where he ranked last out of the 250 boys in his year group at biology, and was in the bottom set in every other science subject. A schoolmaster wrote a report stating “I believe he has ideas about becoming a scientist; on his present showing this is quite ridiculous.”[9] Gurdon explains it is the only document he ever framed; Gurdon also told a reporter “When you have problems like an experiment doesn’t work, which often happens, it’s nice to remind yourself that perhaps after all you are not so good at this job and the schoolmaster may have been right.”[10]

It was during his first term of being taught Science at the school, at the age of 15, that he received a totally damning report from the Biology master (fig. 4). This report resulted from JBG being placed in the bottom position of the lowest form in a group of 250 students of the same age. The report, sent to his housemaster, resulted in him being taken off any further study of Science of any kind at the school. For the rest of his school days, for the next three years, he was given no Science teaching and was placed in a class which studied Ancient Greek, Latin and a modern language, a course intended for those judged to be unsuited for studying any subject in depth.

Eton school report for JBG from Biology master, 1949.

 

Entrance to University was a problem: having sat the Entrance examination in Latin and Greek, the Admissions tutor at Christ Church Oxford University told JBG that he would be accepted for Entrance on condition that he did not plan to study the subject in which he took the Entrance (Classics). Later the Admissions tutor admitted that he had under-filled the college and had his mind on other things; he was Hugh Trevor-Roper, later Lord Dacre, and author of The Last Days of Hitler. In due course it emerged that JBG’s acceptance for Christ Church involved a complicated arrangement between JBG’s uncle, at that time a Fellow of Christ Church, JBG’s school housemaster and a friend of his uncle, Sir John Masterman, who was Master of Worcester College, Oxford and in charge of the wartime Enigma operation at Bletchley, agreeing to accept the housemaster’s son. Such a manoeuvre, and admission to Oxford on those terms, could never happen now. At that time, 1952, it was not very easy to fill a college with paying students. Before entering University, JBG had to take a year off to learn elementary Biology with a private tutor, generously funded by his parents who had already paid several years of Eton fees. He was told that he could formally enter the Department of Zoology course at Oxford if he passed the elementary exams in Physics, Chemistry and Biology in a preliminary year. He survived this and started the course in Zoology at Oxford in 1953. The course was extremely oldfashioned, by today’s standards. A major part of the teaching involved learning Palaeontology, and the names of skeletal parts of dinosaurs. JBG later became a personal friend of Sir Alister Hardy, the Head of that department, through his Oxford aunt (see later).

As the Zoology course came to an end, JBG enquired about the possibility of doing a PhD in Entomology, in accord with his continuing interest in insects. While still a student, he had got permission to go to Oxford University’s nature reserve, namely Wytham Woods, with his butterfly net. No butterflies were to be seen, but he caught the only moving thing, which was a kind of fly. He used the taxonomic reference works to try to identify this “fly.” Having realised that the fly was a Hymenopteron, he was still unable to identify it. He therefore went to the Natural History Museum in London for help. They pronounced that it was in fact a species of sawfly new to Britain. This must have been intensely irritating to the Professor of Entomology, whose main research project was to identify animals and plants in Wytham Woods. JBG was later rejected for PhD work in Entomology. This was a great blessing because the work he would have done in Entomology was not well regarded and had very little, if any, analytical component to it. By his immense good fortune, he was invited to do a PhD with the Oxford University lecturer who taught Developmental Biology, Dr Michael Fischberg.

Fischberg was born in St Petersburg, Russia, in 1919. He was educated in Switzerland and was a PhD student of E. Hadorn. Hadorn in turn was a student of F. Baltzer, who was a student of H. Spemann, himself a student of T. Boveri. This German-Swiss lineage of eminent Developmental Biologists turns out to be the background of a great many of the successful Developmental Biologists of the mid-1950s. Most of those that did not have this background can trace their own training back to R. G. Harrison (1870–1959) of the USA, who pioneered cell culture. Having finished his PhD with Hadorn, Fischberg took a position in the Institute of Animal Genetics under Waddington in Edinburgh, from where he accepted his appointment in the Oxford Zoology department, headed by Professor Sir Alister Hardy, an eminent marine biologist [Royal Society memoirs].

Starting his PhD work in 1956, Fischberg suggested to JBG that he should try to carry out somatic cell nuclear transfer in Xenopus, a procedure for this having been recently published by Briggs and King (1952). The advisability and technical problems that arose at this point are described in the accompanying papers (Gurdon 2013 a,b). Once these technical obstacles had been overcome, largely as a result of good luck, JBG’s work proceeded extraordinarily fast; strongly motivated by early success, he became an intensely hard worker. By the end of his PhD he had succeeded in obtaining normal development of intestinal epithelium cell nuclei transplanted to enucleated eggs of Xenopus. When these tadpoles had eventually reached sexual maturity, he was able to publish a paper entitled “Fertile intestine nuclei.”This was the first decisive evidence that all cells of the body contain the same complete set of genes. This answered a long-standing and important question in the field of Developmental Biology. However it also showed very clearly, as was commented on in JBG’s papers at the time, the remarkable ability of eggs to reprogram somatic cell nuclei back to an embryonic state. Eventually this phenomenon attracted increasingly large interest, and led to the idea of cell replacement using accessible adult cells, such as skin. A key future discovery was that of Martin Evans (Nobel Prize, 2006) that a permanently proliferating embryonic stem cell line could be established from mouse embryos. Under appropriate conditions these cells could be caused to differentiate into all different cell types. The combination of somatic cell nuclear transfer and the derivation of embryonic stem cells in mammals made it realistic to think of cell replacement for human diseases. A huge boost for this idea was later provided by Takahashi and Yamanaka (2006), with their discovery that the overexpression of certain transcription factors can also yield embryonic stem cells from adult somatic tissue. The accompanying Nobel lecture provides more detail of the later scientific part of JBG’s career.

A visit by the Nobel Laureate George Beadle to the Fischberg Group in the Oxford Zoology department in 1960 led to an offer from the California Institute of Technology (CalTech) (previous chairman George Beadle) for JBG to do postdoctoral work there. Fischberg very wisely advised JBG to accept the CalTech offer of postdoctoral work rather than offers from other nuclear transplant labs. Stimulated by his mother’s adventurous spirit, JBG decided to buy a secondhand Chevrolet in New York and drive across the USA to California, using the famous Route 66 (now replaced). He gave lectures as he travelled across the USA and stopped at laboratories of Briggs and King, Alexander Brink (paramutation) etc. He had hoped to become a post-doctoral student of R. Dulbecco at CalTech (Nobel Prize), but the chairman of that department advised against this because JBG had no training in virology. Therefore JBG did his postdoctoral work with Robert Edgar on Bacteriophage Genetics. JBG found he had no aptitude at all for Phage Genetics and decided to return to Britain after one year at CalTech. Nevertheless, that year at CalTech was extremely formative because it provided some acquaintance with Molecular Biology, which had so far entirely escaped his training. During that year he met Sturtevant, a student of Morgan, who pioneered the whole field of Drosophila Genetics. He also got to know Ed Lewis (future Nobel Laureate). Thanks to James Ebert (director of the Department of Embryology, Carnegie Institute of Washington, in Baltimore) JBG visited various labs in the USA at the end of his post-doctoral period and met Donald Brown in Baltimore on that visit. Meantime, the success of the nuclear transfer work in Oxford had led to Michael Fischberg being offered a head of department professorship in Geneva, Switzerland. JBG was offered the teaching position in Oxford vacated by M. Fischberg. JBG returned from California to England via Japan and many other countries over a two-month period. One month of that time he spent in Japan and met Tokindo Okada and made other friends in Japan, including M. Furusawa and subsequently Koichiro Shiokawa.

While doing graduate and postdoctoral work in Oxford, JBG made other contacts and friendships. His mother’s sister lived in Oxford, and he spent much time at her house and visiting famous gardens, fostering a lifelong interest in plants. Through that connection he met Miriam Rothschild, and became a lifelong friend of hers (Van Emden and Gurdon, 2006). This friendship contained, through Miriam Rothschild’s generosity, ski mountaineering holidays based in her house in Wengen. JBG had achieved the British ski club’s Gold standard ski medal, again through relentless practice rather than any natural ability. Also, in accord with his interest in the open air and dogged determination, he became a reasonably accomplished ice figure skater.

Nobel Lecture by Sir John B. Gurdon (42 minutes)

Sir John B. Gurdon delivered his Nobel Lecture on 7 December 2012 at Karolinska Institutet in Stockholm. He was introduced by Professor Urban Lendahl, Chairman of the Nobel Committee for Physiology or Medicine.
Credits: Sveriges Television AB (production)

Copyright © Nobel Media AB 2012

The Nobel Prize in Physiology or Medicine 2012    Lecture (pdf)

Nuclear transfer

In 1958, Gurdon, then at the University of Oxford, successfully cloned a frog using intact nuclei from the somatic cells of a Xenopus tadpole.[14][15] This work was an important extension of work of Briggs and King in 1952 on transplanting nuclei from embryonic blastula cells[16] and the successful induction of polyploidy in fish Stickleback, Gasterosteus aculatus, in 1956 by Har Swarup reported in Nature.[17] However, he could not yet conclusively show that the transplanted nuclei derived from a fully differentiated cell. This was finally shown in 1975 by a group working at the Basel Institute for Immunology in Switzerland.[18] They transplanted a nucleus from an antibody-producing lymphocyte (proof that it was fully differentiated) into an enucleated egg and obtained living tadpoles.

Gurdon’s experiments captured the attention of the scientific community and the tools and techniques he developed for nuclear transfer are still used today. The term clone[19] (from the ancient Greek word κλών (klōn, “twig”)) had already been in use since the beginning of the 20th century in reference to plants. In 1963 the British biologist J. B. S. Haldane, in describing Gurdon’s results, became one of the first to use the word “clone” in reference to animals.

Messenger RNA expression

Gurdon and colleagues also pioneered the use of Xenopus (genus of highly aquatic frog) eggs and oocytes to translate microinjected messenger RNA molecules,[20] a technique which has been widely used to identify the proteins encoded and to study their function.

Recent research

Gurdon’s recent research has focused on analysing intercellular signalling factors involved in cell differentiation, and on elucidating the mechanisms involved in reprogramming the nucleus in transplantation experiments, including the role of histone variants,[21][22] and demethylation of the transplanted DNA.[23]

Reprogramming of Mature Cells

Our lives begin when a fertilized egg divides and forms new cells that, in turn, also divide. These cells are identical in the beginning, but become increasingly varied over time. As a result of this process, our cells become specialized for their location in the body – perhaps in a nerve, a muscle, or a kidney. It was long thought that a mature or specialized cell could not return to an immature state, but this has been proven incorrect.

In 1962, John Gurdon removed the nucleus of a fertilized egg cell from a frog and replaced it with the nucleus of a mature cell taken from a tadpole’s intestine. This modified egg cell grew into a new frog, proving that the mature cell still contained the genetic information needed to form all types of cells. In 2006, Shinya Yamanaka succeeded in identifying a small number of genes within the genome of mice that proved decisive in this process. When activated, skin cells from mice could be reprogrammed to immature stem cells, which, in turn, can grow into all types of cells within the body. In the long-term, these discoveries may lead to new medical treatments.

Shinya Yamanaka

A winding road to pluripotency

http://www.nobelprize.org/nobel_prizes/medicine/laureates/2012/yamanaka-lecture.pdf

http://www.nobelprize.org/nobel_prizes/medicine/laureates/2012/ypdfamanaka-lecture_slides.

Nobel Lecture

46 min.
by Shinya Yamanaka Center for iPS Cell Research and Application (CiRA), Kyoto University, Kyoto 606-8507, Japan.
Gladstone Institute of Cardiovascular Disease, San Francisco, CA 94158, USA.
INTRODUC TION John Gurdon received recognition for his landmark achievement in 1962, which provided the first experimental evidence of reprogramming by the transplantation of amphibian somatic cell nuclei into enucleated oocytes [1]. This breakthrough in technology introduced a new paradigm; that each nucleus of a differentiated cell retains a complete set of blueprints for the whole body, while oocytes possess a certain potential for reprogramming. Inspired by this paradigm shift and subsequent research achievements, we identified four transcription factors that could induce pluripotency in somatic cells by their forced expression and successfully consolidated effective reprogramming methods in mouse cells in 2006 [2] and in human cells in 2007 [3]. The established reprogrammed cells were named “induced pluripotent stem (iPS) cells.” I would like to provide an overview focusing on the experimental background of the generation of iPS cells, and the future perspectives regarding iPS cell research, which has been developing rapidly.

Figure 1. My first experiment as a graduate student. Intravenous injection of a vasoactive molecule platelet activating factor (PAF) caused a transient decrease in blood pressure in dogs (upper panel). We hypothesized that this hypotension would be blocked by pretreatment with a thromboxane A2 inhibitor (lower left panel). Unexpectedly, we observed a profound hypotension (lower right panel).

In 1989, however, my life took a new turn from clinical medicine in orthopedic surgery to basic science research for two reasons. First, I found that I was not a very talented surgeon. Second, I saw many patients suffering from intractable diseases and injuries, which even highly talented surgeons and physicians were not able to cure. For example, I had encountered patients suffering from spinal cord injuries, amyotrophic lateral sclerosis and osteosarcomas. Furthermore, I lost my father due to liver cirrhosis during my residency. Basic medical research is the only way to find cures for these patients. For these reasons, I decided to go back to school. I became a Ph.D. student at Osaka City University Medical School in April of 1989.

Among the many departments at the school, I applied to the Department of Pharmacology, directed by Dr. Kenjiro Yamamoto.  Dr. Ikemoto repeatedly told me that we should not perform research that simply reproduced somebody else’s re-sults. Rather, we should do something unique and new. During my training as a scientist, I was very fortunate to have two types of teachers: namely, great men-tors and unexpected results from my experiments.
My direct mentor at the graduate school was Dr. Katsuyuki Miura. In my first few months as a Ph.D. student, Dr. Miura told me to read as many manuscripts as possible and propose new projects. I felt like I was given a blank canvas and told that I could draw whatever I wanted. This mentorship was very different from what I had experienced during my residency. At the hospital, I’d had little freedom, and had to follow instructions from senior physicians and textbooks. I thought “wow, I like this system!” Another thing that Dr. Miura often told me was that we were competing worldwide. Whatever project you chose, you will compete with other scientists throughout the world, mostly in the U.S. or Europe, on the same or similar projects. This was again very different from my experience at the hospital, where I was competing only with other residents at the same hospital. The idea of “worldwide” competition had never entered my mind when I was working at the hospital. For all of these reasons, I found that basic research was a more suitable career, based on my interests and temperament.
In the summer of 1989, I was still struggling to find my project. Dr. Miura proposed a simpler project to begin my research studies. He suggested that I examine the role of a vasoactive molecule, platelet activating factor (PAF), in dogs to study the regulation of blood pressure (Fig. 1). Because it was known that the intravenous injection of PAF into dogs caused a transient decrease in blood pressure (transient hypotension), Dr. Miura hypothesized that this decrease in blood pressure would be mediated by another vasoactive molecule, thromboxane A2. If that hypothesis was correct, then pretreatment with a thromboxane A2 inhibitor should block the PAF-induced transient decrease in blood pressure. My first experiment, where I treated dogs with an inhibitor of thromboxane A2, was performed based on his hypothesis, and I had expected no decrease in the blood pressure in the pretreated dogs. It should have been a simple experiment suitable for a beginner. However, the result was totally unexpected. In the beginning, the thromboxane A2 inhibitor did not seem to be effective, with subsequent PAF treatment inducing the normal transient decrease in the blood pressure. Surprisingly, however, a few minutes after the treatment, a profound and prolonged decrease in blood pressure was observed, which we had never observed following treatment with PAF alone (Fig. 1). I got so excited! I ran into Dr. Miura’s office to report this result excitedly. Although the result did not support his hypothesis, Dr. Miura responded with excitement, too, and encouraged me to explore the finding further. I spent another two years uncovering the mechanism responsible for this unexpected result [4, 5]. I was extremely lucky to obtain this kind of unexpected result in my very first experiment as a graduate student.

A scandal involving Japanese stem-cell research took a surprising turn Monday when the nation’s most revered researcher in the field, Nobel Prize laureate Shinya Yamanaka, apologized for what he described as poor record-keeping.

The apology came after months of soul-searching in Japan over research ethics. A researcher at the prestigious Riken institute, Haruko Obokata, apologized earlier this month after admitting errors in a paper in the journal Nature that described a possible new method of creating stem cells.

Last week, the head of the Riken panel investigating Dr. Obokata had to resign from the panel after admitting that a paper he co-authored used some of the same improper methods of cutting and pasting images that he had criticized in Dr. Obokata’s work.

On Monday evening, Dr. Yamanaka, a professor at Kyoto University, spoke at a news conference after questions arose about an image in a 2000 paper on which he was the lead author. In the paper, Dr. Yamanaka, then at Nara University, described a protein that played a role in turning embryo cells into cells specific to a part of the body.

The university said it conducted an investigation after Dr. Yamanaka informed administrators about allegations he discovered online that an image in the paper was doctored.

 

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Lonely Receptors: RXR – Jensen, Chambon, and Evans

Larry H. Bernstein, MD, FCAP, Curator

Leaders in Pharmaceutical Intelligence

Series E. 2; 7.2

 

Nuclear receptors provoke RNA production in response to steroid hormones

Albert Lasker Basic Medical Research Award

Pierre Chambon, Ronald Evans and Elwood Jensen

For the discovery of the superfamily of nuclear hormone receptors and elucidation of a unifying mechanism that regulates embryonic development and diverse metabolic pathways.

Hormones control a vast array of biological processes, including embryonic development, growth rate, and body weight. Scientists had known since the early 1900s that tiny hormone doses dramatically alter physiology, but they had no idea that these signaling molecules did so by prodding genes. The 1950s, when Jensen began his work, was the great era of enzymology. Conventional wisdom held that estradiol—the female sex hormone that instigates growth of immature reproductive tissue such as the uterus—entered the cell and underwent a series of chemical reactions that produced a particular compound as a byproduct. This compound—NADPH—is essential for many enzymes’ operations but its small quantities normally limit their productivity. A spike in NADPH concentrations would stimulate growth or other activities by unleashing the enzymes, the reasoning went.

In 1956, Jensen (at the University of Chicago) decided to scrutinize what happened to estradiol within its target tissues, but he had a problem: The hormone is physiologically active in minute quantities, so he needed an extremely sensitive way to track it. He devised an apparatus that tagged it with tritium—a radioactive form of hydrogen—at an efficiency level that had not previously been achieved. This innovation allowed him to detect a trillionth of a gram of estradiol.

When he injected this radioactive substance into immature rats, he noticed that most tissues—skeletal muscle, kidneys and liver, for example—started expelling it within 15 minutes. In contrast, tissues known to respond to the hormone—those of the reproductive tract—held onto it tightly. Furthermore, the hormone showed up in the nuclei of cells, where genes reside. Something there was apparently grabbing the estradiol.

Jensen subsequently showed that his radioactive hormone remained chemically unchanged once inside the cell. Estrogen did not act by being metabolized and producing NADPH, but presumably by performing some job in the nucleus. Subsequent work by Jensen and Jack Gorski established that estradiol converts a protein in the cytoplasm, its receptor, into a form that can migrate to the nucleus, embrace DNA, and turn on specific genes.

From 1962 to 1980, molecular endocrinologists built on Jensen’s work to discover the receptors for the other major steroid hormones—testosterone, progesterone, glucocorticoids, aldosterone, and the steroid-like vitamin D. In addition to Jensen and Gorski, many scientists—notably Bert O’Malley, Jan-Ake Gustafsson, Keith Yamamoto, and the late Gordon Tompkins—made crucial observations during the early days of steroid receptor research.

Clinical Applications of Estrogen-Receptor Detection

Clinicians knew that removing the ovaries or adrenal glands of women with breast cancer would stop tumor growth in one out of three patients, but the molecular basis for this phenomenon was mysterious. Jensen showed that breast cancers with low estrogen-receptor content do not respond to surgical treatment. Receptor status could therefore indicate who would benefit from the procedure and who should skip an unnecessary operation. In the mid-1970s, Jensen and his colleague Craig Jordan found that women with cancers that contain large amounts of estrogen receptor are also likely to benefit from tamoxifen, an anti-estrogen compound that mimics the effect of removing the ovaries or adrenal glands. The other patients—those with small numbers of receptors—could immediately move on to chemotherapy that might combat their disease rather than waiting months to find out that the tumors were growing despite tamoxifen treatment. By 1980, Jensen’s test had become a standard part of care for breast cancer patients.

In the meantime, Jensen set about generating antibodies that bound the receptor—a tool that provided a more reliable way to measure receptor quantities in excised breast tumor specimens. His work has transformed the treatment of breast cancer patients and saves or prolongs more than 100,000 lives annually.

Long-Lost Relatives

By the early 1980s, interest in molecular endocrinology had shifted toward the rapidly developing area of gene control. Chambon and Evans had long wondered how genes turn on and off, and recognized nuclear hormone signaling as the best system for studying regulated gene transcription. They wanted to know exactly how nuclear receptors provoke RNA production in response to steroid hormones. To manipulate and analyze the receptors, they would need to isolate the genes for them.

By late 1985 and early 1986, Evans (at the Salk Institute in La Jolla) and Chambon (at the Institute of Genetics and Molecular and Cellular Biology in Strasbourg, France) had pieced together the glucocorticoid and estrogen receptor genes, respectively. They noticed that the sequences resembled that of v-erbA, a miscreant viral protein that fosters uncontrolled cell growth. This observation raised the possibility that v-erbA and its well-behaved cellular counterpart, c-erbA, would also bind DNA and control gene activity in response to some chemical activator, or ligand. In 1986, Evans and Björn Vennström simultaneously reported that c-erbA was a thyroid hormone receptor that was related to the steroid hormone receptors, thus uniting the fields of thyroid and steroid biology.

Chambon and Evans set to work deconstructing the glucocorticoid and estrogen receptors. By creating mutations at different spots and probing which activities the resulting proteins lost, they dissected the receptor into three domains: one bound hormone, one bound DNA, and one activated target genes. The structure of each domain strongly resembled the analogous one in the other receptor.

Chambon and Evans wanted to match other members of the growing receptor gene family with their chemical triggers. Because the DNA- and ligand-binding regions functioned independently, it was possible to hook the DNA-binding domain of, say, the glucocorticoid receptor to the ligand-binding domain of another receptor whose ligand was unknown. The ligand for that receptor would then activate a glucocorticoid-responsive test gene.

Evans would use this method to identify ligands for several novel members of the nuclear receptor family, and both he and Chambon exploited it to discover a physiologically crucial receptor. In the late 1970s, scientists had suggested that the physiologically active derivative of vitamin A, retinoic acid, could exert its effects by binding to a nuclear receptor. This nutrient is essential from fertilization through adulthood, and researchers were eager to understand its activities on a molecular level. During embryonic development, deficiency of retinoic acid impairs formation of most organs, and the compound can hinder cancer cell proliferation. So Chambon set out to find a receptor that responded to retinoic acid. He isolated a member of the nuclear receptor gene family whose production increased in breast cancer cells that slowed their growth upon exposure to the chemical. Simultaneously, Evans identified the same protein. He tested whether more than a dozen compounds activated an unknown receptor and one passed: retinoic acid.

Remarkably, in 1986, the two scientists had independently—and unbeknownst to each other—identified the same retinoic acid receptor, a molecule of tremendous significance. The discovery of this molecule provided an entry point for detailing vitamin A biology.

Rx for Lonely Receptors: RXR

The list of presumptive nuclear receptors was growing quickly as scientists realized that the common DNA sequences provided a handle with which to grab these molecules from the genome. Because their chemical activators weren’t known, they were called “orphan” receptors, and researchers were keen on “adopting” them to ligands. Some of these ligands, they reasoned, would represent previously unknown classes of gene activators. The test system that Chambon and Evans used to match up retinoic acid with its receptor, in which they stitched an unknown ligand-binding domain to a DNA-binding domain for a receptor with known target sequences, could be harnessed to accomplish this task.

Evans had identified some potential nuclear receptors from fruit flies. He decided to pursue a human orphan receptor that closely resembled one of these receptor genes, reasoning that a protein that functioned in both flies and mammals was likely to perform an important job.

This receptor responded to retinoic acid in intact cells but did not bind it in the test tube, so Evans called it the Retinoid X Receptor (RXR), thinking that its ligand was some retinoic acid derivative. In cells, enzymes convert retinoic acid to metabolites and it seemed possible that one of these compounds was RXR’s ligand. In 1992, Evans’s group and one at Hoffmann-La Roche discovered that 9-cis-retinoic acid, a stereoisomer of retinoic acid, could activate RXR, identifying the first new receptor ligand in 25 years. This finding launched the orphan receptor field because it provided strong evidence that the strategy could unearth previously unknown ligands.

In the meantime, Chambon had found that the purified retinoic acid receptor, in contrast to the estrogen receptor, did not bind efficiently to its target DNA. Other nuclear receptors, too, needed help grasping genes. In the test tube, the retinoic acid, thyroid hormone, and vitamin D3 receptors could attach well to their target DNA only when supplemented with cellular material, which presumably contained some crucial substance. Chambon and Michael Rosenfeld independently purified a single protein that performed this feat, and it turned out to be none other than RXR. This ability of RXR to pair with other receptors—forming so-called heterodimers—would turn out to be key for switching on many orphan receptors. These heterodimeric couplings yield large numbers of distinct gene-controlling entities.

Chambon revealed the power of mixing and matching in these molecular duos through his thorough and extensive genetic manipulations in mice. He has shown that vitamin A exerts its wide-ranging effects on organ development in the embryo through the action of eight different forms of the retinoic acid receptor and six different forms of RXR, interacting with each other in a multitude of combinations.

Clinical Applications of the Superfamily Work

The concept of RXR as a promiscuous heterodimeric partner for certain nuclear receptors led to the unexpected identification of a number of clinically relevant receptors. These proteins include the peroxisome proliferator-activated receptor (PPAR), which stimulates fat-cell maturation and sits at the center of Type 2 diabetes and a number of lipid-related disorders; the liver X receptors (LXRs) and bile acid receptor (FXR), which help manage cholesterol homeostasis; and the steroid and xenobiotic receptor (PXR), which turns on enzymes that dispose of chemicals that need to be detoxified, such as drugs.

Because the nuclear receptors wield such physiological power, they have provided excellent targets for disease treatment. The anti-diabetes compounds glitazones, for example, work by stimulating PPAR, and the clinically used lipid-lowering medications called fibrates work by binding a closely related receptor, PPAR. Retinoic acid therapy has dramatically altered the prognosis of people with acute promyelocytic leukemia by triggering specialization of the immature white blood cells that accumulate in these individuals. The three-dimensional structure of nuclear receptors with and without their ligands, which Chambon and his colleagues first solved, promises to accelerate drug discovery in the whole field.

Nuclear hormone receptors have touched on human health in other ways as well. Genetic perturbations in the genes for these proteins cause a variety of illnesses. For example, certain forms of rickets arise from mutations in the vitamin D receptor and several disorders of male sexual differentiation stem from defects in the androgen receptor.

The discoveries of Jensen, Chambon, and Evans revealed an unimagined superfamily of proteins. At the start of this work almost 50 years ago, no one would have anticipated that steroids, thyroid hormone, retinoids, vitamin D, fatty acids, bile acids, and many lipid-based drugs transmit their signal through similar pathways. Four dozen human nuclear receptors are now known, and scientists are working out the roles of these proteins in normal and aberrant physiology. These discoveries have revolutionized the fields of endocrinology and metabolism, and pointed toward new tactics for drug discovery.

by Evelyn Strauss, Ph.D.

 

The 2004 Lasker Award for Basic Medical Research will be presented to Elwood Jensen, Ph.D., the Charles B. Huggins Distinguished Service Professor Emeritus in the Ben May Institute for Cancer Research at the University of Chicago, one of three scientists whose discoveries “revolutionized the fields of endocrinology and metabolism,” according to the award citation. Jensen’s work had a rapid, direct and lasting impact on treatment and prevention of breast cancer.

The Lasker Awards are the nation’s most distinguished honor for outstanding contributions to basic and clinical medical research. Often called “America’s Nobels,” the Lasker Award has been awarded to 68 scientists who subsequently went on to receive the Nobel Prize, including 15 in the last 10 years.

Jensen will share the basic medical research award with two colleagues, Pierre Chambon, of the Institute of Genetics and Molecular and Cellular Biology (Strasbourg, France), and Ronald M. Evans of the Salk Institute for Biological Studies (La Jolla, California) and the Howard Hughes Medical Institute.

They were selected for their discovery of the “superfamily of nuclear hormone receptors and the elucidation of a unifying mechanism that regulates embryonic development and diverse metabolic pathways.” The implications of this research for understanding human disease and accelerating drug discovery “have been profound and hold much promise for the future,” notes the announcement from the Lasker Foundation.

Jensen is being honored for his pioneering research on how steroid hormones, such as estrogen, exert their influence. His discoveries explained how these hormones work, which has led to the development of drugs that can enhance or inhibit the process.

Hormones control a vast array of biological processes, including embryonic development, growth rate and body weight. Before Jensen, however, the way which hormones cause these effects was “a complete mystery,” recalled Gene DeSombre, Ph.D., professor emeritus at the University of Chicago, who worked with Jensen in the Ben May Institute as a post-doctoral fellow and then as a colleague.

In the 1950s, biochemists thought a hormone entered a cell, where a series of oxidation and reductions reactions with the estrogen provided needed energy for the growth stimulation and other specific actions shown by estrogens.

From the late 1950s to the 1970s Jensen entirely overturned that notion. Working with estrogen, he proved that hormones do not undergo chemical change. Instead, they bind to a receptor protein within the cell. This hormone-receptor complex then travels to the cell nucleus, where it regulates gene expression.

At the time, this idea was heresy. “That really got him into some hot water,” recalled DeSombre. “Jensen struggled quite a lot,” echoes Shutsung Liao, Ph.D., another Ben May colleague, who subsequently found a similar system for testosterone action. But for Jensen, just getting into hot water was a struggle. When he first presented preliminary data at a 1958 meeting in Vienna, only five people attended, three of whom were the other speakers. More than 1,000 attended a simultaneous symposium on the metabolic processing of estrogen.

In the next 20 years, Jensen convinced his colleagues by publishing a series of major and highly original discoveries in four related areas of hormone research:

  • Jensen discovered the estrogen receptor, the first receptor found for any hormone. In 1958, using a radioactive marker, he showed that only the tissues that respond to estrogen, such as those of the female reproductive tract, were able to concentrate injected estrogen from the blood. This specific uptake suggested that these cells must contain binding proteins, which he called “estrogen receptors.”
  • In 1967, Jensen and Jack Gorski of the University of Wisconsin showed that these putative receptors were macromolecules that could be extracted from these tissues. With this method, Jensen showed that when estrogen bound to this receptor, the compound then migrated to the nucleus where it bound avidly and activated specific genes, stimulating new RNA synthesis.
  • By 1968, Jensen had devised a reliable test for the presence of estrogen receptors in breast cancer cells. It had been known for decades that about one-third of premenopausal women who had advanced breast cancer would respond to estrogen blockade brought about by removing their ovaries, the source of estrogen, but there was no way to predict which women would respond. In 1971, Jensen showed that women with receptor-rich breast cancers often have remissions following removal of the sources of estrogen, but cancers that contain few or no estrogen receptors do not respond to estrogen-blocking therapy.
  • By 1977, Jensen and Geoffrey Greene, Ph.D., also in the University of Chicago’s Ben May Institute, had developed monoclonal antibodies directed against estrogen receptors, which enabled then to quickly and accurately detect and count estrogen receptors in breast and other tumors. By 1980, this test had become a standard part of care for breast cancer patients

This work “transformed the treatment of breast cancer patients,” notes the Lasker Foundation, “and saves or prolongs more than a 100,000 lives annually.”

”Jensen’s revolutionary discovery of estrogen receptors is beyond doubt one of the major achievements in biochemical endocrinology of our time,” said DeSombre. “His work is hallmarked by great technical ingenuity and conceptual novelty. His promulgation of simple yet profound ideas concerning the role of receptors in estrogen action have been of the greatest importance for research on the basic and clinical physiology not only of estrogens but also of all other categories of steroid hormones.”

By the early 1970s, Jensen was searching for chemical, rather than surgical, ways to shield estrogen-dependent tumors from circulating hormones. He and colleague Craig Jordan (then at the Worcester Foundation for Experimental Biology in Massachusetts) subsequently found that women with cancers that contain large amounts of estrogen receptor are also likely to benefit from tamoxifen, a compound that blocks some of the effects of estrogen. Patients with few or no receptors could immediately move on to chemotherapy rather than waiting months to find out that the tumors were growing despite tamoxifen treatment.

Following Jensen’s lead, researchers soon found that the receptors for the other major steroid hormones, such as testosterone, progesterone, and cortisone, worked essentially the same way.

In 1986, Pierre Chambon and Ronald Evans separately but simultaneously discovered that the steroid hormone receptors were merely the tip of the iceberg of what would turn out to be a large family of structurally related nuclear receptors, now known to consist of 48 members. Evans and Chambon unearthed a number of these receptors, which revealed new regulatory systems that control the body’s response to essential nutrients (such as Vitamin A), fat-soluble signaling molecules (such as fatty acids and bile acids), and drugs (such as the glitazones used to treat Type 2 diabetes and retinoic acid for certain forms of acute leukemia).

These three individuals “created the field of nuclear hormone receptor research, which now occupies a large area of biological and medical investigation,” said Dr. Joseph L. Goldstein, chairman of the international jury of researchers that selects recipients of the Lasker Awards, and recipient of the Lasker Award for Basic Medical Research and the Nobel Prize in Medicine in 1985.

They revealed the “unexpected and unifying mechanism by which many signaling molecules regulate a plethora of key physiological pathways that operate from embryonic development through adulthood. They discovered a family of proteins that allows chemicals as diverse as steroid hormones, Vitamin A, and thyroid hormone to perform in the body.”

Jensen, known for concluding his lectures in verse, neatly summed up what his extraordinary series of discoveries might mean to a woman who has been diagnosed with breast cancer:

“A lady with growth neoplastic
Thought surgical ablation too drastic.
She preferred that her ill
Could be cured with a pill,
Which today is no longer fantastic.”

JBC THEMATIC MINIREVIEW SERIES 2011

Nuclear Receptors in Biology and Diseases

Thematic Minireview Series on Nuclear Receptors in Biology and Diseases

Sohaib Khan and Jerry B Lingrel

Although a connection between breast cancer and the ovary was made by Sir George Beatson in 1896 and estrogen was purified in 1920, it remained puzzling as to how the hormone exerted its biological effects. In the late 1950s, when Elwood Jensen delved into this problem by asking, essentially, “What does tissue do with this hormone?” little did he know that his quest would lead to the establishment of the nuclear receptor field. The late 1950s was the era of intermediary metabolism and enzymology, when steroid hormones were considered likely substrates in the formation of metabolites that functioned as cofactors in an essential metabolic pathway. The biological responses to estrogens and other steroids were thought to be mediated by enzymes. Against this background and prevailing dogma, Jensen and colleagues defined the biochemical mechanisms by which steroid hormones exert their effects. While working at the University of Chicago’s Ben May Institute for Cancer Research, they synthesized tritium-labeled estradiol and concurrently developed a new method to measure its uptake in biological material. These tools enabled them to determine the biochemical fate of physiological amounts of hormone. They discovered that the reproductive tissues of the immature rat contain characteristic hormone-binding components with which estradiol reacts to induce uterine growth without itself being chemically changed. From the close correlation between the inhibition of binding and inhibition of growth response, Jensen established that the binding substances were receptors. Thus, we saw the birth of the first member of the nuclear receptor family (known as the estrogen receptor). These findings stimulated the search for other physiological receptors, and the pioneering works by Pierre Chambon, Ronald Evans, Jan-Åke Gustafsson, Bert W. O’Malley, and Keith Yamamoto led to the discoveries of the glucocorticoid receptor (GR),2 progesterone receptor, retinoic acid receptor, and orphan receptors. In a rather short span of time, the nuclear receptor family has grown into a 49-member-strong “superfamily.” This is a family whose members, functioning as sequence-specific transcription factors, have defined the many intricacies of the mechanism of transcription. These ligand-dependent transcription factors generally possess similar “domain organizations,” of which the DNA-binding domain and the ligand-binding domain are critical in amplifying the hormonal signals via the receptor target genes. The nuclear receptor family is divided into four groups: (i) Group 1 is composed of steroid hormone receptors that control target gene transcription by binding as homodimers to response element (RE) palindromes; (ii) in Group 2, the nuclear receptors heterodimerize with retinoid X receptor and generally bind to direct repeat REs; (iii) Group 3 consists of those orphan receptors that function as homodimers and bind to direct repeat REs; and (iv) orphan receptors in Group 4 function as monomers and bind to single REs.

Since the early demonstration by Jack Gorski and Jensen that the estrogen receptor (ER) activates transcription, the nuclear receptor field has come a long way. In addition to the first cloning of the polymerase II transcription factors (GR and ER cDNAs), of note is the discovery of steroid receptor coactivators (SRCs), a truly major piece of the transcriptional jigsaw puzzle, described by the laboratories of O’Malley and Myles Brown. The induction of coactivators and corepressors in the transcriptional machinery has expanded tremendously our understanding of this complex process. We now know that ligand binding to the respective receptors triggers a fascinating chain of events, including the translocation of the receptors to the nucleus, ligand-induced changes in the receptor conformations, receptor dimerization, interaction with the target gene promoter elements, recruitment of coactivators (or corepressors), chromatin remodeling, and subsequent interaction with the polymerase II complex to initiate transcription.

By virtue of their abilities to regulate a myriad of human developmental and physiological functions (reproduction, development, metabolism), nuclear receptors have been implicated in a wide range of diseases, such as cancer, diabetes, obesity, etc. Not surprisingly, drug companies are spending billions of dollars to develop medicines for cancer and metabolic disorders that involve nuclear receptors. More than 50 years after the discovery of the ER, the scientific community owes Jensen and other founding members of the nuclear receptor family much gratitude, for they have taken us through a remarkable expedition filled with eureka moments to understand how hormones and other ligands function!

This thematic minireview series will cover a range of topics in the nuclear receptor field. The minireviews include the current studies of identifying subtypes of the GR. Different receptors arise from alternative mRNA splicing and from the use of different promoter start sites and post-translational modifications, such as phosphorylation. The series covers the physiological roles of the different GRs. The field of orphan nuclear receptors and the search for possible ligands also are reviewed. One minireview concentrates largely on the following nuclear receptors: peroxisome proliferator-activated receptor (PPAR) α, PPARγ, Rev-erbα, and retinoic acid receptor-related orphan receptor α. ERα was the first identified and has been studied the most, whereas ERβ has not been studied in the same detail. ERβ is very important, and one of the minireviews provides a summary of the new biological functions that are being ascribed to it. Also, the development of small molecule inhibitors for the ER will be considered. An important aspect of nuclear receptor function is how these receptors function in transcription. The role of transcriptional coactivators in nuclear receptor gene regulation will be reviewed as well as how signal amplification and interaction are involved in transcription regulation by steroids. The SRC/p160 family of coregulators includes SRC-1, SRC-2, and SRC-3, and the latter has been shown to act as an oncogene, particularly in breast cancer. Molecular analysis of its role in breast cancer progression and metastasis will be the focus of one of the minireviews. In addition, interactions of nuclear receptors with the genome will be reviewed, as will the role of the homeodomain protein HoxB13 in specifying the cellular response to androgens. Mining nuclear receptor cistromes and how nuclear receptors reset metabolism also will be considered. The association of nuclear receptors (e.g. PPARδ) with physiological functions, such as circadian rhythm and muscle functions, will also be addressed. Finally, the role of nuclear receptors in disease using the retinoid X receptor α/β knock-out and transgenic mouse model skin syndromes and asthma will be reviewed. These are diverse and important topics that are critical in understanding the regulation of nuclear receptors and the biological roles they play in normal function and disease.

The Nuclear Receptor Superfamily: A Rosetta Stone for Physiology

Ronald M. Evans
Howard Hughes Medical Institute, Gene Expression Laboratory, The Salk Institute for Biological Studies, La Jolla, California 92037
Molecular Endocrinology 19(6):1429–143   http://dx.doi.org:/10.1210/me.2005-0046

In the December 1985 issue of Nature, we described the cloning of the first nuclear receptor cDNA encoding the human glucocorticoid receptor (GR) (1). In the 20 yr since that event, our field has witnessed a quantum leap by the subsequent discovery and functional elaboration of the nuclear receptor superfamily (2)—a family whose history is linked to the evolution of the entire animal kingdom and whose actions, by decoding the genome, span the vast diversity of biological functions from development to physiology, pathology, and treatment. A messenger is an envoy or courier charged with transmitting a communication or message. In one sense, the cloning of that first messenger (the GR) represented the completion of a prediction that began with Elwood Jensen’s characterization of the first steroid receptor protein (3) and continued with the pioneering work of others in the steroid receptor field (including Gorski, O’Malley, Gustafsson, and Yamamoto). Yet, like the discovery of the Rosetta stone in 1799, the revelation of the GR sequence heralded a completely unpredictable demarcation in the field, helping to solve mysteries unearthed nearly 100 yr ago as well as opening a portal to the future. The beginnings of the adventure lie in disciplines such as medicine and nutrition, which gave rise to the emergent field of endocrinology in the first half of the last century. The purification of chemical messengers ultimately known as hormones from organs and vitamins from foods spurred the study of these compounds and their physiologic effects on the body. At about the same time, the field of molecular biology was emerging from the disciplines of chemistry, physics, and their application to biological problems such as the structure of DNA and the molecular events surrounding its replication and transcription. It would not be until the late 1960s and 1970s that endocrinology and molecular biology would begin to intersect as the link between receptors and transcriptional control were being laid down. During this time, the work of Jensen (4) and Gorski (5) identified a high-affinity estrogen receptor (ER) that suggested an action in the nucleus. Gordon Tomkins and his associates (J. Baxter, G. Ringold, E. B. Thompson, H. Samuels, H. Bourne, and others) were one of the most creative forces studying glucocorticoid action (6). Concurrent work by O’Malley, Gustafsson, and Yamamoto provided further, important evidence supporting a link between steroid receptor action and transcription (see accompanying perspective articles in this issue of Molecular Endocrinology). But whereas the steroid hormone field continued to evolve in this direction, it is of interest to note that the mechanism of action of thyroid hormone and retinoids remained clouded and controversial until the eventual cloning of their receptors in the late 1980s. Likewise, no one had foreseen the possibility that other lipophilic molecules (like oxysterols, bile acids, and fatty acids) would also function through a similar mechanism, or that other steroid receptor-like proteins existed that would play an important role in transcriptional regulation of so many diverse pathways. Thus, the GR isolation in 1985 led to the concept of a hidden superfamily of receptors that in a very real way provided the needed molecular code to unravel the puzzle of physiologic homeostasis.

Unconventional Gene-Ology

The study of RNA tumor viruses was ascendant, and the concept that they evolved by pirating key signaling pathways greatly influenced my future studies. With this training, I went on to work with Jim Darnell at the Rockefeller University on adenovirus transcription, a model brought to the lab by Lennart Philipson. At the time, adenovirus was one of the best tools to study programmed gene expression in an animal cell. My sole focus was to localize the elusive major late promoter, which provided my first Nature paper (7). Ed Ziff, a newly hired assistant professor from Cambridge, brought innovative unpublished DNA and RNA sequencing techniques that, after much technical angst, allowed us to sequence the major late promoter and derive the structure of the first eukaryotic polymerase II promoter (8). This thrilling result convinced me that the problem of gene control could be solved at the molecular level. Our next goal, which I shared with Michael Harpold in the Darnell lab, was to translate the concepts developed around adenovirus into cellular systems. My model was to analyze the glucocorticoid and thyroid hormone regulation of the GH gene. Under the strict federal guidelines for newly approved recombinant DNA research, we cloned the GH cDNA in 1977 and the first genomic clones in 1978 (9) after I moved on to The Salk Institute. However, to fully address the hormone signaling problem, I realized that it would be necessary to clone the GR and thyroid hormone receptors (TRs), which began in earnest in 1981. Up until that time, the purification and cloning of any polymerase II transcription factor had eluded researchers because of their low abundance. Four years later, the GR would be the first transcription factor for a defined response element to be cloned, sequenced, and functionally identified.

A Rock and A Hard Place

A key question was whether the GR protein encoded by the receptor was sufficient, when expressed in a heterologous cell, to convey the hormonal message. Before the publication, a new postdoc, Vincent Giguere, began tinkering with the isolated GR, trying to address this question. The rate of development of any field is limited by the existing techniques and depends on the development of new ones. Vincent devised a revolutionary technique—the cotransfection assay that required two plasmids to be taken up in the same cell, the expression vector to be transcribed, the encoded protein to be functional and an inducible promoter linked to a chloramphenicol acetyltransferase reporter in the nucleus ready to flicker on (10, 12). With so many variables and unknowns, I was stunned and expressionless when it worked the very first time. Cotransfection was an easy, fast, and quantitative technique. It would become (and still remains) the dominant assay to characterize receptor function. It would also become the mainstay for drug discovery in the pharmaceutical industry. The development of this technique proved a great advantage because existing technology involved creating stable cell lines, a tedious process prone to integration artifacts that ultimately could not match the explosive pace of the field. Indeed, within 4 months Stan and Vincent had fully characterized 27 insertional mutants delineating the DBD, LBD, and two activation domains (12). The route to understanding the signaling mechanism now had a solid structural foundation. A serendipitous gift to my retroviral origins was the homology of the GR sequence to the v-erbA oncogene product of the avian erythroblastosis virus genome (13). With this discovery, erbA advanced to a candidate nuclear transcription factor potentially involved in a signal transduction pathway. Thus, while Stan concentrated on the GR, Cary began to delve into the erbA discovery. Within months of the GR publication, the human c-erbA gene was in hand (14). Unbeknownst to us, Bjorn Vennstrom, one of the first to characterize the avian erythroblastosis virus genome, had also isolated c-erbA and was searching for a function. Based on the low homology of the LBD region to the GR and ER, both groups deduced that the imaginary erbA ligand would be nonsteroidal.

The work of our two groups (15, 16), published in December of 1986, broadened the principles of the signal transduction pathway by demonstrating that thyroid and steroid hormone receptor signaling had a common evolutionary origin and provided an entree to understand how mutations within a receptor could activate it to an oncogene. Although we did not know it at the time, this work would also lead us to the concept of the corepressor. In the meantime, my student, Catherine Thompson, zeroed in on an erb-A-related gene and soon identified a second TR expressed at high levels in the central nervous system (17). Thus came into existence the and forms of the TR. Jeff Arriza, the third graduate student in the lab, purified a genomic fragment that had weakly hybridized to the GR resulting in the isolation of the human mineralocorticoid receptor (MR) (18). MR proved to have an at least 10-fold higher affinity for glucocorticoids than the GR itself and was further distinguished by its ability to bind and be activated by aldosterone. This enabled the development of GR- and MR-selective drugs such as the recent MR antagonist eplerenone. Thus, in a 2-yr time span our lab had progressed on three distinct, albeit related, receptor systems, and in doing so molecular biology and endocrinology were irrevocably linked. The field of molecular endocrinology (and coincidentally the eponymous journal) was born.

Ligands From Stone

I have often been asked how we could handle so many divergent systems. Indeed, from a medical perspective, these systems seem widely unrelated. Studies of ER, progesterone receptor, and androgen receptor (AR) fall under reproductive physiology, vitamin D under bone and mineral metabolism, with vitamin A part of nutritional science. Medical fields are naturally idiosyncratic because of the specialized knowledge required to conduct experiments. With my training as a molecular biologist, physiology was the complex output of genes and thus control of gene expression was the overriding problem. This conceptual approach had a great unifying effect because all receptors transduce their signaling through the gene. As an “outsider,” my goal was to exploit multiple receptor systems to seek general principles. This philosophical approach afforded us a freedom to redefine the signaling problem from the nucleus outward and thus even poorly characterized, even unknown, physiologic systems fell into the crosshairs of our molecular gun.

Vincent, while screening a testes Fig. 1. Models of Nuclear Receptor Structure Top, Original hand-shaped wire model (circa 1992) of the nuclear receptor DBD. Bottom, Schematic representation of the GR DBD. Conserved residues in zinc fingers, P-box and D-box are indicated isolated what would become the vitamin A or retinoic acid receptor (RAR) (19). Initially, Vincent thought he had isolated the AR, although this later proved not to be the case. By that stage, the lab had perfected a new technique—the domain swap—by which the GR DBD could be introduced into any receptor and confers on the chimeric protein the ability to activate a mouse mammary tumor virus reporter. This clever technique, independently developed in the Chambon lab, would prove to be essential. Effectively, the domain swap would enable us to screen for ligands without any knowledge of their physiologic function. Activation of a target gene was all that was needed! By creating this GR chimera, Vincent was able to screen the new receptor against a ligand cocktail including androgens, steroids, thyroid hormone, cholesterol, and the vitamin A metabolite retinoic acid. From the first assay, it was clear that he had isolated a high-affinity selective RAR that had no response to any other test ligand. Thus, without knowing any true direct target gene for retinoic acid, we were nonetheless able to isolate and characterize its receptor. Remarkably, Martin Petkovich in the Chambon lab isolated the same gene. Once again, this is an example where a new technique offered an entirely new approach to a problem. Both papers were published in the December 1987 issue of Nature (19, 20). With the combination of steroids, thyroid hormones, and vitamin A, the three elemental components of the nuclear receptor superfamily were in hand. By the time the RAR papers were published, Vincent with Na Yang, had already isolated two estrogen-related receptors termed ERR1 and 2 that would represent the first true orphan receptors in the evolving superfamily (21). A third receptor (ERR3) would be isolated 10 yr later (22). The three ERRs are distinguished by their ability to activate through ER response elements, but required no ligand. However, of potential major medical relevance, estrogen antagonists such as 4-hydroxy-tamoxifen silences ERR constitutive activity (23). The superfamily was growing exponentially, transforming into a new field, driven by a new breed of exceptional students and fellows attracted by the mechanics of transcription and its emerging link to physiology. For example, the RAR and TR offered an unprecedented look at understanding the action of vitamin A as a morphogen and the role of thyroxin in setting the basal metabolic rate of the body. We were a relatively small group, and our decision to work on multiple different receptor systems created a unique environment. Because there was so little overlap between projects, postdocs and students readily discussed all results, exchanged reagents and freely collaborated, resulting in a tremendous acceleration of progress. The high level of camaraderie was powered by the joie de vivre of the exciting discoveries and the ability of our family of students and postdocs to each adopt their own receptors. We all felt we were in a golden age and even more was to come.

In 1989, Jan Sap in Vennstrom’s group and Klaus Damm in our group demonstrated that the TR becomes oncogenic by mutation in the LBD (24, 25). Although we expected ligand-independent activation, it was clearly a constituitive repressor becoming the first example of a dominant-negative oncogene. The concept of the dominant-negative oncogene had been proposed one year earlier by Ira Herskowitz (26). This discovery changed our thinking on hormone action, and repression soon would be shown to be a common feature of receptor antagonists. David Mangelsdorf, who had arrived in the lab the year before was captivated by the glow of weakly hybridizing DNA bands and, in 1989, had amassed his own collection of orphan receptors, among which was the future retinoid X receptor (RXR) (27). In search for biological activity, a candidate ligand was found in lipid extracts from outdated human blood. However, the key test came from demonstrating that addition of all-trans retinoic acid to cultured cells would lead to its rapid metabolism coupled with the release of an inducing activity for RXR, which we termed retinoid X. David and his benchmate, Rich Heyman, began working on the chemistry of this inducer along with Gregor Eichele and Christine Thaller, then at Baylor College of Medicine (Houston, TX). This work led to the identification of 9-cis retinoic acid by our lab and a group at Hoffman LaRoche (Nutley, NJ) (28, 29). Like the retinal molecule in rhodopsin, 9-cis-retinoic acid represents the exploitation of retinoid isomerization by nature to control a key signaling pathway. More importantly, in the 39 yr since the discovery of aldosterone in 1953, this revelation would reawaken and reinvent the single most defining but dormant tool of endocrinology—ligand discovery. Indeed, the discovery that new receptors could lead to new ligands opened up an entirely new avenue of research. Like the puzzle of the structure of the benzene ring, which was solved in 1890 when Fredrick Kekule dreamed of a snake biting its own tail, the physiologic head of the “endocrine snake” and the molecular biology tail had come full circle. The era of reverse endocrinology was now upon us.

Response Elements: Deciphering The Scripts

One problem in addressing the downstream effects of our newly discovered receptors was that their response elements and target genes were by definition unknown. Kaz Umesono delved into this mystery and would produce a paradigm shift that would both solve the problem and further unify the field. With the view that the DBD functioned as a molecular receptor for its cognate hormone response element, meticulous mutational studies revealed two key DBD sequences, termed the P-box and D-box, that controlled the process (30).

The D-box was shown to direct dimerization, a feature previously thought to be unique to the LBD. One perplexing point was that the P-boxes of the nonsteroidal receptors were conserved, leading to the improbable prediction that many different receptors would recognize the same target sequence. By manual compilation and comparison of all known response elements, Kaz proposed a core hexamer— AGGTCA—as the prototypic common target sequence. By requiring the half-site to be an obligate hexamer an underlying pattern—the direct repeat—emerged. In the direct repeat paradigm, we proposed that half-site spacing, not sequence difference, was the key ingredient to distinguishing the response elements. The metric was referred to as the 3-4-5 rule (31). According to the rule, direct repeats of AGGTCA spaced by three nucleotides, would be a vitamin D response element (DR-3), the same repeat spaced by four nucleotides a thyroid hormone response element (DR-4), and the same repeat spaced by five nucleotides a vitamin A response element (DR-5). Eventually, all steps from 0–5 on the DR ladder would be filled (Fig. 2). The validity of this paradigm was ensured by a crystal structure solved in collaboration with Paul Sigler’s group at Yale (32). Indeed, of the remaining 40 nonsteroidal receptors, all but three can be demonstrated to have a preferred binding site within some component of the direct repeat ladder. Exceptions include SHP and DAX, which lack DBDs, and farnesoid X receptor (FXR) that binds to the ecdysone response element as a palindrome with zero spacing. Kaz’s insight, by drawing commonality from diversity, came to solve a problem that impacted on virtually every receptor. Remarkably, each new receptor in the superfamily could immediately be assigned a place on the ladder. The ladder also provided a simple means to conduct a ligand screening assay in absence of any knowledge of an endogenous target gene. Kaz’s ladder was a turbo charge for the field. The next major advance in the field was the discovery of the RXR heterodimer. Although we knew that retinoid and thyroid receptors required a nuclear competence factor for DNA binding, its identity was unknown. We tested RXR, but our initial experiments were flawed. Of the first four papers describing the discovery, that from Chambon’s lab was most elegant because they simply purified an activity to homogeneity to find RXR (33)! Rosenfeld was first to publish, and Ozato, Pfahl and Kliewer all concurred (34–37). Tony Oro and Pang Yao in our lab soon published that the ecdysone receptor functions as a heterodimer with ultraspiracle, the insect homolog of RXR (38, 39), revealing that the ancient origins of the heterodimer which arose before the divergence of vertebrates and invertebrates.

Reverse Endocrinology: Decoding Physiology

The orphan receptors would transform our view of endocrine physiology with unexpected links to toxicology, nutrition, cholesterol, and triglyceride metabolism as well as to a myriad of diseases including atherosclerosis, diabetes, and cancer. The three RXR isoforms formed the core with 14 heterodimer partners including the vitamin D receptor (VDR), TR/, and RAR//. The initial adopters of orphan receptors included Giguere, Mangelsdorf, Weinberger, Bruce Blumberg, Steve Kliewer, and Barry Forman. Barry unlocked the first secret to for peroxisome proliferator-activated receptor (PPAR) by identifying prostaglandin J2 (PGJ2) as a high-affinity ligand (40). The second step, in collaboration with Peter Tontonoz in Bruce Spiegleman’s lab, revealed that PGJ2 was adipogenic in cell lines and perhaps more importantly that the synthetic antidiabetic drug Troglitazone was a potent PPAR agonist (41). Similar work was conducted and published by Kliewer, who had now moved to Glaxo (42). By acquiring a ligand, a physiologic response, and a drug, PPAR was suddenly transported to the center of a physiologic cyclone that would spin into its own specialty field. Since 1995, more than 1000 papers (see PubMed) have been published on PPAR and its natural and synthetic ligands. This early work illuminated the molecular strategy of reverse endocrinology and the emerging importance of the orphan receptors in human disease and drug discovery. Cary returned to the lab for a sabbatical and, with Barry, demonstrated that FXR was responsive to farnesoids and other molecules in the mevalonate pathway. The findings by Mangelsdorf that liver X receptors (LXRs) bound oxysterols (43) and by Kliewer, Mangelsdorf, and Forman that FXR is a bile acid receptor (44–46) provided a whole new conceptual approach to cholesterol and triglyceride homeostasis. The steroid and xenobiotic receptors (SXR)/pregnane X receptor (PXR) (47–49) and the constituitive androstane receptor (CAR) (50) respond to xenobiotics to activate genes for P450 Fig. 2. Examples of Receptor Heterodimer Combinations that Fill the Direct Repeat (DR) Response Element Ladder from DR1 to DR5 Evans enzymes, conjugation and transport systems that detoxify drugs, foreign chemicals, and endogenous steroids. RXR and its associated heterodimeric partners quickly established a new branch of physiology, shedding its dependence on endocrine glands and allowing the body to decode signals from environmental toxins, dietary nutrients, and common metabolites of intermediary metabolism.

Continued…

ROCK OF AGES

The human body is, after all a living machine, a complex device that consumes and uses energy to sustain itself, defend against predators, and ultimately reproduce. One might reasonably ask, “If the superfamily acts through a common molecular template, can the family as a whole be viewed as a functional entity?” In other words, is there yet some overarching principle that we have yet to grasp. . . and might this imaginary principle lie at the heart of systems physiology? Simply stated, what led to the evolution of integrated physiology as the functional output of the superfamily? One obvious speculation is survival. To survive, all organisms must be able to acquire, absorb, distribute, store, and use energy. The receptors are exquisitely evolved to manage fuel—everything from dietary and endogenous fats (PPARs), cholesterol (LXR, FXR), sugar mobilization (GR), salt (MR), and calcium (VDR) balance and maintenance of basal metabolic rate (TR). Because only a fraction of the material we voluntarily place in our bodies is nutritional, the xenobiotic receptors (PXR, CAR) are specialized to defend against the innumerable toxins in our environment. Survival also means reproduction, which is controlled by the gonadal steroid receptors (progesterone receptor, ER, AR). However, fertility is dependent on nutritional status, indicating the presumptive communication between these two branches of the family. The third key component managed by the nuclear receptor family is inflammation. During viral, bacterial, or fungal infection, the inflammatory response defends the body while suppressing appetite, conserving fuel, and encouraging sleep (associated with cytokine release). However, if needed, even an ill body is capable of defending itself by releasing adrenal steroids, mobilizing massive amounts of fuel, and transiently suppressing inflammation. In fact, clinically, (with the exception of hormone replacement) glucocorticoids are only used as antiinflammatory agents. Other receptors including the RARs, LXRs, PPAR and , and vitamin D receptor protect against inflammation. Thus, nature evolved within the structure of the receptor the combined ability to manage energy and inflammation, indicating the important duality between these two systems. In aggregate, this commonality between distinct physiologic branches suggests that the superfamily might be approached as an intact functional dynamic entity.

Historically, endocrinologists and geneticists rarely saw eye to eye. As I have indicated in this perspective article, the disciplines have now become united in a new subject—transcriptional physiology. With this in mind, we might expect the existence of larger organizational principles that establish how the various evolutionary branches of the superfamily integrate to form whole body physiology. The existence of molecular rules governing the function and evolution of a megagenetic entity like the nuclear receptor superfamily, if correct, may be useful in understanding complex human disease and provide a conceptual basis to create more effective pharmacology. With so much accomplished in the last 20 yr (see Fig. 3), there are glimpses of clarity—enough to see the enormity and wonder of the problem and enough to know there is still a long and challenging voyage ahead. But who knows, the next breakthrough may only be a stone’s throw away.

http://press.endocrine.org/doi/pdf/10.1210/me.2005-0046

 

Pierre Chambon MD

Recipient of the Canada Gairdner International Award, 2010
“For the elucidation of fundamental mechanisms of transcription in animal cells and to the discovery of the nuclear receptor superfamily.”

Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Illkirch-Graffenstaden, France

Dr. Pierre Chambon is Honorary Professor at the College de France (Paris), and Emeritus Professor at the Faculté de Médecine of the Strasbourg University. He was the Founder and former Director of the IGBMC, and also the Founder and former Director of the Institut Clinique de la Souris (ICS/MCI), in Strasbourg.

Dr. Pierre Chambon is a world expert in the fields of gene structure, and transcriptional control of gene expression. During the last 25 years his studies on the structure and function of nuclear receptors has changed our concept of signal transduction and endocrinology. By cloning the estrogen and progesterone receptors, and discovering the retinoic acid receptor family, he markedly contributed to the discovery of the superfamily of nuclear receptors and to the elucidation of their universal mechanism of action that links transcription, physiology and pathology. Through extensive site-directed mutagenesis and genetic studies in the mouse, Pierre Chambon has unveiled the paramount importance of nuclear receptor signaling in embryonic development and homeostasis at the adult stage. The discoveries of Pierre Chambon have revolutionized the fields of development, endocrinology and metabolism, and their disorders, pointing to new tactics for drug discovery, and finding important applications in biotechnology and modern medicine.

These scientific achievements are logically inscribed in an uninterrupted series of discoveries made by Pierre Chambon over the last 45 years in the field of transcriptional control of gene expression in higher eukaryotes: discovery of PolyADPribose (1963), discovery of multiple RNA polymerases differently sensitive to a-amanitin (1969), contribution to elucidation of chromatin structure: the Nucleosome (1974), discovery of animal split genes (1977), discovery of enhancer elements (1981), discovery of multiple promoter elements and their cognate factors (1980-1993).

Pierre Chambon has received numerous international awards, including the 2004 Lasker Basic Medical Research Award for the discovery of the superfamily of nuclear hormone receptors and the elucidation of a unifying mechanism that regulates embryonic development and diverse metabolic pathways. He is a member of the French Académie des Sciences, and also a Foreign Member of the National Academy of Sciences (USA) and of the Royal Swedish Academy of Sciences. Pierre Chambon serves on a number of editorial boards, including Cell, and Molecular Cell. Pierre Chambon is author of more than 900 publications. He has been ranked fourth among most prominent life scientists for the 1983-2002 period.

An Interview with Pierre Chambon
2004 Albert Lasker Basic Medical Research Award
http://www.laskerfoundation.org/media/v_chambon.htm

Pierre Chambon, MD

​Honorary Professor at the Collège-de-France and Professor of Molecular Biology and Genetics, Institute for Advanced Study, University of Strasbourg; Group Leader, Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Illkirch-Graffenstaden, Strasburg, France

A pioneer in the fields of gene structure and transcriptional control of gene expression, Dr. Chambon has fundamentally changed our understanding of signal transduction, which has led to revolutionary new tactics for drug discovery. His work elucidated how molecules that promote gene transcription are organized and regulated in eukaryotic organisms and, independently of Dr. Ronald Evans, he discovered in 1987 the retinoid receptor families, which led to the discovery and characterization of the superfamily of nuclear hormone receptors, including steroid and retinoid receptors.

Dr. Chambon’s previous research led to the discovery of PolyADPribose, multiple RNA polymerases differentially sensitive to α-amaniti, and has markedly contributed to the elucidation of the nucleosome and chromatin structure, as well as to the discovery of animal split genes, DNA sequences called enhancer elements, and multiple promoter elements and their cognate factors. These discoveries have greatly enhanced understanding of embryonic development and cell differentiation. To further studies of various nuclear receptors, Dr. Chambon has developed a method that allows in the mouse the generation of somatic mutations of any gene, at any time, and in any specific cell type, a tool valuable in generating mouse models of cancer.

In 1994, Dr. Chambon took on the role of founding a major research institute in France. As the first director of IGBMC, he built the institute to encompass hundreds of top researchers and multiple research programs funded by public agencies and private industry. In 2002, he founded and was the first director of the Institut Clinique de la Souris in Strasbourg. In these positions, he has succeeded in supporting and influencing a generation of scientists.

Career Highlights

​2010  Canada Gairdner International Award

2004  Albert Lasker Basic Medical Research Award

2003  Alfred P. Sloan, Jr., Prize, General Motors Cancer Foundation

1999  Louisa Gross Horwitz Prize, Columbia University

1998  Robert A. Welch Award in Chemistry

1991  Prix Louis-Jeantet de médecine, Fondation Louis-Jeantet

1990  Sir Hans Krebs Medal, Federation of European Biochemical Societies

1988  King Faisal International Prize for Science, King Faisal Foundation

1987  Harvey Prize, Technicon-Israel Institute of Technology

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Minireviews In This Series:

Thematic Minireview Series on Nuclear Receptors in Biology and Diseases

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Steroid Receptor Coactivator (SRC) Family: Masters of Systems Biology

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Small Molecule Inhibitors as Probes for Estrogen and Androgen Receptor Action

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Cellular Processing of the Glucocorticoid Receptor Gene and Protein: New Mechanisms for Generating Tissue Specific Actions of Glucocorticoids

Robert H Oakley and John A Cidlowski

Endogenous Ligands for Nuclear Receptors: Digging Deeper

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