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Archive for the ‘BioSimilars’ Category

Reporter: Aviva Lev-Ari, PhD, RN

Demonstrate Biosimilarity with 100% confidence. Everytime

While offering greater flexibility, new FDA biosimilar guidelines lack specificity, nothing in the development can be taken for granted.

Develop biosimilars that exhibit comparability in every required category and avoid ever having a biosimilar application rejected. With so much at stake, are you 100% confident of demonstrating comparability every time? 

Demonstrate Biosimilarity is your opportunity to get first hand case studies from the leading biosimilar and generic drug developers as well as the FDA on the best approaches to…

  1. Interpret regulatory ambiguity and determine how much similarity must be demonstrated to gain approval and achieve interchangeability
  2. Ensure stability and analytical comparability as well as comparability in safety and PK/PD by optimizing your quality assessment strategy
  3. Reduce the impact of immunogenicity in your biosimilar drug and discover how to translate this regulatory expectation into a clinical trial concept
  4. Optimize your approaches to protein characterization with practical guidance from industry leading analytical scientists and service providers

Demonstrate Biosimilarity will tackle burning issues surrounding naming and pricing policiesoriginators defence strategiesmanufacturing challenges andhow to identify the best target for biosimilar development. Achieve technical insights and obtain cutting edge intelligence from 16 pharma case studies showcasing biosimilar best practise.

Attend and gain first hand testimony from the FDA, that combined with this depth of insight will give you the information you need to move quickly and decisively to get your biosimilar approved.

What you will learn? 

Attend Demonstrate Biosimilarity to:

  • Learn how to effectively monitor the higher-order structure and associated structural dynamics of your biosimilar drug molecules by optimizing your approach to comparability studies with practical guidance from Biogen Idec
  •  Expand your knowledge of how protein aggregates interact with the immune system and how this understanding can be used to reduce immunogenicitywith the Chief Medical Research Officer at the FDA
  •  More effectively determine the extent of physiochemical, pre-clinical and clinical characterization required to demonstrate biosimilarity and gain approval with case studies from Novartis and Sandoz
  • Enhance harmonization of your biosimilar data with a comprehensive comparison of the EMEA Vs USA regulatory landscape with Sandoz, Pfizerand Wokhardt
  • Get insight from MedImmune to achieve comparability when test methods are changed during the product life cycle and a non-inferior, equivalent, or superior replacement study model has been selected
  • Understand fully the applications of bioassays to determine product potency, aid biological characterization, test comparability, and determine stability with expert advice and clinical data from Teva Pharmaceuticals
  • Get a first hand guide from the FDA regarding quantitation and characterization of protein aggregates in biosimilars to ensure quality and safety of products,consistency of manufacture between lots and comparability when the manufacturing process has been changed

Does the FDA biosimilar guidance go far enough? Not if you want to operate with 100% confidence.

In fact the FDA still wants to take a cautious case by case approach. Complex biosimilar comparability studies are inherently risky and the consequences of a rejected submission are dramatic. This means that an open dialogue with FDA & other developers is essential.

Our recent industry survey highlighted two key desires for drug developers:

 

To know exactly how other drug developers are tackling challenges such as structural comparability, immunogenicity and interchangeability

What the FDA is currently thinking and how this would apply to their development programs

In response to this demand for insight and support we’ve assembled the FDA alongside the industry’s best at Demonstrate Biosimilarity Washington DC (13-14th February).

 

Learn from the testimony of 18 industry speakers including Sandoz, Teva, Wokhardt, GSK, Pfizer, MedImmune, Biogen Idec, Amgen, Novartis, Merck and senior FDA representatives dedicated to answering these questions.  This will ensure that you can effectively achieve comparability , demonstrate biosimilarity and avoid costly failed submissions. View the agenda now.

Overcome challenges such as:

 

  • How do I assess the level of biological purity needed to match my innovator product and avoid making several submission to regulators?
  • Is it truly possible to achieve interchangeability and how can I convince patients and physicians of the equivalence of my biosimilar and ensure market access?
  • What are the best practises to decrease immunogenicity risk to increase my chances of achieving comparability?
  • Where can I obtain a suitable reference product to allow me to begin characterization?
  • What is the FDA’s current thinking on the criteria for analytical, stability, safety and PK/PD comparability?

Download the brochure now to view the full agenda, workshops & speaker line up.

http://demonstrate-biosimilarity.com/download-brochure?utm_campaign=2924FIERCE&utm_medium=email&utm_source=Eloqua&elq=268b14bad28e4a9f979fc60b45a9c3c6&elqCampaignId= 

This meeting will provide you with unrivalled access to 15 case study lead presentations from pioneering biosimilar and generic drug developers sharing their innovative new approaches.

Learn how your peers are decreasing the clinical work required, minimising the impact of immunogenicity, achieving interchangeability and how they define targets for biosimilar development.

If that isn’t enough, the FDA will be giving keynote presentations on the regulatory expectations regarding aggregates and comparability as well as minimizing the impact of immunogenicity by understanding the role of protein aggregates in unwanted immunogenicity.

SPEAKERS

http://demonstrate-biosimilarity.com/speakers?utm_campaign=2924FIERCE&utm_medium=email&utm_source=Eloqua&elq=268b14bad28e4a9f979fc60b45a9c3c6&elqCampaignId=

AGENDA:

Day One

13th February, 2013

8.00 Registration

8.55 Chair’s Opening Remarks 

Optimizing Quality Assessments: Biochemical and Physiochemical Properties

9.00 Regulatory Expectations Regarding Aggregates and Comparability

• A guide from the FDA regarding quantitation and characterization of protein aggregates to ensure quality and safety, consistency of manufacture and comparability when the manufacturing process is being changed

• Overcoming challenges associated with characterization of the aggregates’ full size range to maximize safety information

Ewa Marszal, Chemist, Laboratory of Plasma Derivatives, Division of Haematology, CBER, FDA

9.30 An Industry Perspective: Optimizing Approaches to Protein Characterization in the Development of Biosimilars

• Practical guidance for optimizing analytical characterization of commercial products

• Understanding the innovation required in both technical development and clinical development

• Devising a systematic engineering approach to match biosimilar to reference product

Roxana Butoi, Manager, Biosimilars, GSK

10.00 Solution Spotlight: Analytical methods for monitoring biosimilar glycosylation

Scott Barksdale, Director, Business Development, Procognia

10.15 Speed Networking & Morning Refreshments

11.45 CASE STUDY: Implementing Advanced Analytical Methods and Regulatory Approved Comparability Strategies

• Numerous case studies demonstrating when test methods are changed during the product life cycle and a non-inferior, equivalent, or superior replacement study model has been selected based on the intended use of the new test method

• How to set risk-based acceptance criteria from product specifications and existing manufacturing process knowledge

Stephan Krause, PDA Task Force Leader for Analytical Methods, and Principal Scientist, Analytical Biochemistry, MedImmune

12.15 Application of Hydrogen/Deuterium Exchange with Mass Spec Detection (H/DX-MS) to Assess Comparability 

• Applications of instrumental hardware and computer software to enable H/DX-MS to be employed in a practical and routine way to assess biosimilarity

• Optimizing comparability studies to monitor the higherorder structure and associated dynamics of biosimilar drugs

Steven Berkowitz, Principal Investigator, Analytical Development, Biogen Idec

12.45 Effective use of Bioassays to Streamline Biosimilar Development 

• Applications of bioassays to determine product potency, aid biological characterization, and test comparability

• Bioassays as a bioanalytical tool in support of pre clinical and clinical studies throughout the span of biosimilar development

• Developing an assay strategy and clear understanding of regulatory expectations, development and implementation of validated biological assays to ensure approval

Patrick Liu, Senior Director and Global Head of Bioassays, Teva Pharmaceuticals

1:15 Lunch & Networking

2.15 CASE STUDY: Correcting Biases in Light Obscuration and Light Scattering Measurements of Protein Particles 

• A demonstration of the applications of optical models for measuring of protein particles

• Several case studies involving protein aggregates, examining size errors and the practicality of corrections for biosimilar development

Dean Ripple, Leader, Bioprocess Measurements Group, National Institute of Standards and Technology

Demonstrating Biosimilarity: Biochemical and Physiochemical Properties

Roxana Butoi, Manager, Biosimilars, GSK 

Stephan KrausePDA Task Force Leader for Analytical Methods, and Principal Scientist, Analytical Biochemistry, MedImmune

Steven Berkowitz, Principal Investigator, Analytical Development, Biogen Idec

Patrick Liu, Senior Director and Global Head of Bioassays, Teva Pharmaceuticals

3.15 Afternoon Refreshments & Networking  

Achieving Interchangeability with a Biosimilar Product

3.45 Application of Biophysical Techniques in Comparability Exercises: Quantitative Assessment of Spectral Similarity

• Effective use of biophysical tools, including circular dichroism spectroscopy to provide qualitative assessment of the similarity in higher order structure for biological molecules

• Using statistical analysis to provide a more quantitative evaluation of spectral similarity

Qin Zou, Senior Principal Scientist, BioProcess Analytics, Pfizer  

4.15 The Momenta Approach to Developing Biosimilars and Potentially Interchangeable Biologics

• Establishing biosimilarity and potential interchangeability by focussing on “comparison” between RPP and biosimilar

• An overview of Momenta’s key takeaways from the recently issued FDA draft guidance

Jim Roach, SVP, Development and Chief Medical Officer, Momenta Pharmaceuticals

4.45 Comparability and Biosimilarity – Two Sides of the Same (or a Different) Coin? 

• Compare and contrast the comparability and biosimilarity paradigms, with consideration for the impact of Quality by Design on these product development strategies

• The challenges and future directions of product characterization for biosimilars

Brent Kendrick, Director of Analytical Sciences, Amgen

5.15 Chair’s Closing Remark

 

Day Two

14th February, 2013

8.15 Registration

9.10 Chair’s opening remarks

9.15 Analysis of the Biosimilar Development Pipeline

• Gain a better understanding of how the biosimilar market will develop and evolve in light of the biosimilarity guidelines

• Understand when products will begin entering the U.S. and European markets

• What different development approaches are companies taking?

• What will be the involvement of companies in the US/EU

vs. those in developing countries?

Ronald Rader, President, Biotechnology Information Institute

9.45 Minimizing the Impact of Immunogenicity Understanding the Role of Protein Aggregates in Unwanted Immunogenicity

• How subvisible protein aggregates may interact with the immune system, their potential impact on product safety and efficacy

• An FDA perspective on the current regulatory considerations pertaining to the control of these particulates

Jack Ragheb, Chief Medical Research Officer, CDER, FDA

10.15 Morning Refreshments & Networking

Navigating the Regulatory and Legal Environment for Biosimilars

11.00 Comparison of the EMEA and USA Regulation for Biosimilar Development

• A review of the current state of initiatives for biosimilars in both EMEA and USA

• Perspective on how regulatory uncertainty could be reduced in the implementation of quality by design arguments

• A comprehensive comparison of the EMEA Vs USA landscape an the intricacies of harmonization

Ajaz Hussain, Chief Scientific Officer, Workhardt

11.30 An Industry Perspective: USA Current and Future Regulatory Setting for Biosimilars 

• Understanding the need to maximize productivity of FDA biosimilars development meetings

• Identifying and justifying differences between structural and functional characterization

• Negotiating regulatory landscape for clinical development and determining the required magnitude of the program

• Pursuing interchangeability for your biosimilar product without FDA guidance

John Pakulski, Senior Director and Head US Biopharmaceutical Regulatory Affairs, Sandoz

12.00 Biosimilar Regulation Roundtable Session 

• An opportunity for delegates to discuss with the regulators and regulatory experts the recent FDA biosimilar guidelines

• Collaboratively discuss the impact of the regulation and strategies to comply with it

12.45 Lunch & Networking

2.00 A Practical Guide and Overview of Current Strategies of Biocomparability and Biosimilarity 

• Industry perspective on the current guidance from EMEA and FDA for biocomparability

• Current strategies to assess the the extent of physiochemical, pre-clinical and clinical characterization based on the stage of development

• Emerging guidance on biosimilarity and the implications on the pre-clinical and clinical development programs for biosimilars

• Use of biomarkers in the biocomparability exercise: Are we there yet?

Shefali Kakar, Senior Fellow, Clinical Pharmacology, Oncology Business Unit, Novartis

2.30 Understand the Nuances and Implications of the FDA Guidelines on Biosimilars

• A detailed examination of the content of the recently released FDA guidelines and how to best understand the requirements for quantity of data, sources of material and types of studies permitted

• What kind of potential exists for increased efficiency, collaboration and cost-effectiveness in the U.S?

• The repercussions of important FDA decisions that have been made regarding user fees to be paid by companies in order to submit an application for a biosimilar

Helen Hartman, Regulatory Affairs Strategist, Pfizer

3.00 Afternoon Refreshments & Networking

Optimizing Approaches for Biosimilar Production and Manufacture

3.30 CASE STUDY: Evaluation of Comparability due to Changes in Scale-up, Process, Manufacturing Site, and Formulation 

• A case study of a preliminary comparability study used to evaluate the changes due to scale-up, manufacturing site, process and formulation of batches used in phases I/II and III

• A detailed overview of the extended characterization results from this study

• Preliminary assessment of comparability studies to establish the type of analytical testing required to correlate manufacturing changes to the product characteristics in the final comparability testing

Soundara Soundararajan, Principal Scientist, Bioprocess Development, Merck

4.00 Biosimilars: The Age of Post-Patent Medicine

• How will the thorny issues of safety, efficacy and cost (and in that order) impact the role of biosimilars in 21st century healthcare

• A detailed look at the challenges associated with demonstrating biosimilarity to the relevant regulatory bodies

Peter Pitts, President, Center for Medicine in the Public Interest

4.30 Chair’s Closing Remarks

 

Workshops

Pre Conference Workshops: 12th February 2013

Workshop A) 08.00 – 11.00: Measurement, Characterization and Impactof Impurities for Biosimilars

Biotechnology and biosimilar products have substantial differences fromchemical entities in their starting materials, manufacturing processes, productcharacteristics, stability profiles, and interactions with containers and closures.Each of these can impact the nature of the impurities present in the finalproduct.

This workshop will provide an overview of these differences with links tothe current regulatory expectations and notes on current ‘best practices’for impurities assessment during development.

  • Impurities in Biotechnology/Biosimilar Products – What Makes themCritical?

– What are the specific guidance requirements for biosimilar productimpurities?

– What elements impact meaningful, reliable specifications for processand product impurities?

– How are the risks of impurities managed during development?

  • Example of Critical Process-Related Impurities: Host Cell Proteins

– What are the key requirements for measuring host cell proteins fromvarious expression systems?

– How should host cell protein assays be selected, optimized, and validated?

  • Example of Critical Product-Related Impurities: Particulates

– What types of particulates are of concern?

– How do we measure particulates?

  • Example of Critical Container/Closure Related Impurities: Extractables/Leachables

– How do we identify the extractables and leachables?

– How can extractables or leachables affect the product?

You will leave this workshop with a detailed understanding of the impact of key impurities in biosimilar development, through case study examples ofeach, to review the current and emerging issues for biotechnology productsassociated with each.

Led By: Nadine Ritter, Senior CMC Consultant, Biologics Consulting Group

 

Workshop B) 12.00 – 15.00: Strategies for an Abbreviated Clinical Programfor Biosimilar mAbs

This workshop is designed to give you a practical guide to develop theoptimum clinical strategy for developing a biosimilar to minimize the size ofthe clinical program require to demonstrate biosimilarityIn this workshop you will:

  • Understand how to design an abbreviated clinical program for biosimilardrugs
  • Learn to optimize phase I by developing a streamlined FIM PK study usingreference product and PK equivalence as endpoints
  • Discuss best practices for phase III dose and time response design
  • Develop solutions to challenges associated with safety, immunogenicity, interchangeability and extrapolation across multiple indications

You will leave this workshop with a step by step guide to taking a biosimilarthrough clinical development that will minimize the amount of clinical workrequired without compromising the quality or quantity of clinical evidence.

Led by: Partha Roy, Principle Consultant, PAREXEL Consulting

Please note that workshop B runs at the same time as workshop C – so you cannot attend both.

Workshop C) 12.00 – 15.00: Biosimilars: Is the Risk worth the Reward?

This workshop will demonstrate how you can capitalize on the recentregulatory developments, and offer all of the information you need tomove quickly and decisively to turn the streamlined biosimilars processinto a lucrative commercial opportunity.In this workshop you will:

  • Gain an understanding of the potential of the biosimilar market andassess the potential entry routes available for your business
  • Get an overview via numerous case studies of the latest progress inthe biosimilar field and discover how you can capitalize on the latestdevelopments
  • Understand the complex issue of biosimilar ROI and discusspractical strategies to maximize your return
  • Hear both provider and payer perspectives to gain a betterunderstanding of how you can cater to both of their needs

You will leave this workshop with all the information you need todevelop an effective commercially viable biosimilar development strategy.

Led by: James Harris, Chief Executive Officer, Healthcare Economics LLC

Please note that workshop B runs at the same time as workshop C – so you cannot attend both.

 

Workshop D) 15.30 – 18.30: Gain a Biosimilar Market Overview:Present and Future Challenges

Biosimilars present a new set of challenges for regulatory authoritieswhen compared with conventional generics. After many years in theslow lane, changes are driving new momentum in the market forbiosimilarsIn this workshop you will:

  • Analyze with industry leaders the present and future actions of themain players in biosimilar market in different regions of the world tohelp identify best practises from varying geo-specific approaches
  • Get an understanding of the patents used for the first generation ofapproved biopharmaceuticals and discover how to capitalize onpatents about to expire to open up new opportunities in the biosimilarmarket
  • Understand the critical issues for healthcare professionals surroundingthe use of biosimilars to make informed treatment decisions

You will leave this workshop with a greater understanding of thebiosimilar market place and an actionable biosimilar strategyincorporating the best practises discussed during this case study anddiscussion lead workshop.

Led by: Leandro Mieravilla, Global Market Manager mAbs, Cassara Biotech

 

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Breakthrough Digestive Disorders Research: Conditions affecting the Gastrointestinal Tract.

Reporter: Aviva Lev-Ari, PhD, RN

 

Forthcoming Electronic Book on

Metabolism and MetabolOMICS, 2013

Larry H. Bernstein, MD, FCAP and Ritu Saxena, Ph.D., Editors

Book will cover innovations in

  • Digestive Disorders GENOMICS,
  • Pharmaco-Therapy for gut infalmmation,
  • Genetic Immunology,
  • Enzymatic-therapy,
  • Bacterial infection in the gut and pharmaco-therapies
  • Cancer Biology and Therapy

of the following most common digestive disorders today

In the meantime, we are sharing the encouraging news, that is, that the symptoms of digestive disorders can be alleviated, and often completely eliminated, with the right combination of medication, dietary changes, exercise, weight loss, stress reduction and surgery.

It’s all detailed in an important new research report from Johns Hopkins — rated #1 of America’s best hospitals for 21 consecutive years 1991-2011 by U.S. News & World Report.

The 2013 Johns Hopkins Digestive Disorders White Paper

Johns Hopkins Digestive Disorders White Paper

Your Digestive Expert, H. Franklin Herlong, M.D. Adjunct Professor of MedicineJohns Hopkins University School of Medicine

The expertise you need, in language you can understand and use

In The 2013 Johns Hopkins Digestive Disorders White Paper, you will discover exciting advances and the most useful, current information to help you prevent or treat conditions affecting the digestive tract.

You’ll find a thorough overview of what the medical field knows about upper and lower digestive tract disorders (including everything from gastroesophageal reflux disease [GERD] to peptic ulcers, and irritable bowel syndrome to colorectal polyps) and conditions that affect the liver, gallbladder and pancreas.

You will learn how to prevent these diseases and, when symptoms arise, the best ways for you and your doctor to diagnose and treat them. The Johns Hopkins White Papers redefine the term “informed consumer.” In The 2013 Johns Hopkins Digestive Disorders White Paper, specialists from Johns Hopkins University School of Medicine report in depth on the latest digestive disorders prevention strategies and treatments. Thousands of Americans rely on Johns Hopkins expertise to help them manage their digestive disorders.

In The 2013 Johns Hopkins Digestive Disorders White Paper you’ll get a thorough overview of what the medical field knows about the most common digestive disorders today. You’ll find a wealth of news you can use about:

  • Celiac disease
  • Constipation
  • Crohn’s disease
  • Diarrhea
  • Diverticulosis and diverticulitis
  • Gallstones
  • Gastritis
  • GERD
  • Hiatal hernia
  • Irritable bowel syndrome
  • Ulcerative colitis
  • Ulcers

and more…

Timely Information Backed by Johns Hopkins Resources and Expertise

The symptoms of digestive disorders can be alleviated, and often completely eliminated, with the right combination of medication, dietary changes, exercise, weight loss, stress reduction and, as a last resort, surgery.

Learning as much as possible about the causes, effects and treatments for your digestive disorder is the first step toward living a fuller life with minimal discomfort and physical limitations.

The 2013 Johns Hopkins Digestive Disorders White Paper is designed to help you ensure the best outcome. Use what you learn to help you:

  • Recognize and respond to symptoms and changes as they occur.
  • Communicate effectively with your doctor, ask informed questions and understand the answers.
  • Make the right decisions, based on an understanding of the newest drugs, the latest treatments and the most promising research.
  • Take control over your condition and act out of knowledge rather than fear.

Tips for optimal digestive health

  • Maybe It’s Not “Just Heartburn”: Occasional heartburn can be treated with over-the-counter antacids. But if you have any of these symptoms, talk to your doctor to rule out more serious problems.
  • Should You Try Probiotics? Evidence is mounting that these “friendly bacteria” can help treat many digestive problems, such as IBS and Crohn’s disease. See how they work and are used, and whether they might relieve your gastrointestinal issues.
  • New Ways to Look Inside: The benefits and drawbacks of patient-friendly imaging tools including the “video pill” and virtual colonoscopy. How do state-of-the-art tools compare with established diagnostic exams?
  • Making Friends with Fiber: Getting enough dietary fiber is an easy way to prevent or treat a wide variety of digestive complaints. See which foods deliver the most fiber.
  • How to Avoid a Foodborne Illness: Follow these guidelines to choose, store, prepare and serve food in ways that minimize the health risks that result in 76 million infections and 325,000 hospitalizations annually.

SOURCE:

http://www.johnshopkinshealthalerts.com/contact_us/

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Nanotech Therapy for Breast Cancer

Author/ Curator ; Tilda Barliya PhD

Breast cancer is the second most common cancer worldwide after lung cancer, the fifth most common cause of cancer death, and the leading cause of cancer death in women. The global burden of breast cancer exceeds all other cancers and the incidence rates of breast cancer are increasing (Jemel. A CA cancer J Clin 2010:60; 277-300). (Nature Reviews Clinical Oncology to coincide with the 2010 San Antonio Breast Cancer Symposiumhttp://www.nature.com/nrclinonc/focus/breast-cancer/index.html).

The heterogeneity of breast cancers makes them both a fascinating and challenging solid tumor to diagnose and treat. Triple-negative breast cancers in particular are difficult to define—this tumor subgroup lacks expression of HER2, the estrogen receptor and progesterone receptor and do not respond to hormonal therapies or HER2-targeted therapies (owing to the lack of expression of these targets)—and these tumors are associated with a poor prognosis; thus, new systemic therapies are desperately needed. Luca Gianni and coauthors review the evidence for the biology of this subtype, which shares genetic and morphologic similarities with the basal-like breast cancer subtype but also represents a biologically distinct subtype that is heterogeneous. They also discuss potential treatment options, including poly(ADP ribose) polymerase (PARP) inhibitors, which have shown promising efficacy and safety profiles in phase I and II clinical trials in patients with triple-negative breast cancer.

Breast cancers with a BRCA mutation leave the cell susceptible such that PARP inhibition combined with this genetic defect cannot repair DNA breaks resulting in cell death—an effect not observed in normal cells because the BRCA function compensates for PARP inhibition. Importantly, BRCA deficiency and sensitivity to PARP inhibition does not seem to be restricted to a particular histology but rather the BRCA genotype.

One of the greatest issues in oncology is tumor heterogeneity as well as the detection and validation of biomarkers that can aid in treatment decisions. As breast cancers represent a multitude of different diseases with intratumoral and intertumoral genetic and epigenetic alterations, the next challenge will be to understand how these defects arise during disease progression and learn more about the development of mechanisms of resistance to therapies. (Nature Reviews Clinical Oncology to coincide with the 2010 San Antonio Breast Cancer Symposiumhttp://www.nature.com/nrclinonc/focus/breast-cancer/index.html).

Generally, breast tumors are categorized into four different stages based upon their size, location, and evidence of metastasis (www.cancer.org).  Treatment options are also determined by the stage, hormone  (ER/PR), human epidermal growth factor receptor 2 (HER-2/neu) and gene (BRCA1) Status of breast tumors.

Many different types of nano-delivery systems with different materials and physio-chemical properties have been developed for application in breast cancer. We previously discussed in depth the application of liposomal doxorubicin, albumin-bound paclitaxel (Abraxane) and I’d like to shift the discussion to a completely different player in breast cancer progression TNF alpha.

TNF-α

Tumor necrosis factor-α (TNF-α) is an important pro-inflammatory cytokine in the development and progress in human cancer and was shown to induce mammary tumors through through the activation of p42/p44 MAPK, JNK, PI3-K/Akt pathways (http://www.ncbi.nlm.nih.gov/pubmed/18061162), (http://www.ncbi.nlm.nih.gov/pubmed/21476000). Among its roles, TNF-α  is thought to be pro-angiogenic. Paradoxically, it is also a potent anti-vascular cytokine at higher doses (it was named for its anti-tumor activity) and can be used clinically to destroy tumor vasculature. More so TNF-alpha is able to initiate cellular apoptosis and it is possible that these apoptotic pathways are deactivated in tumor cells (http://jbiol.com/content/8/9/85)

Unfortunately, TNF-α has powerful and toxic systemic side effects and has only limited uses at present. Much work is under way to devise ways of targeting TNF-α specifically to tumors.

A nanoparticle delivery system, consisting of PEG coated gold nanoparticle loaded with TNF-α, was constructed to maximize the tumor damage and minimize the systemic toxicity of TNF-α (Visaria et al 2006; Visaria RK, Griffi n RJ, Williams BW, et al. 2006. Enhancement of tumor thermal therapy using gold nanoparticle-assisted tumor necrosis factoralpha delivery. Mol Cancer Ther, 5:1014–20). Combination of local heating and nanoparticle-based delivery of TNF-α resulted in enhanced therapeutic effi cacy than either treatment alone.

Thermally-induced tumor growth delay was enhanced by pretreatment with the nanoparticle, when given intravenously at the proper dosage and timing. Tumor blood fl ow suppression, as well as tumor perfusion defects, suggested vascular damage-mediated tumor cell killing. Surprisingly, following intravenous administration, little to no accumulation in the RES (eg, liver and spleen) or other healthy organs of the animals was observed (Paciotti et al 2004).

Phase I clinical trials of this conjugate, subsequently termed “CYT-6091” also known as Aurmine (CytImmune Scientific Inc)(http://www.cytimmune.com/go.cfm?do=page.view&pid=26) are currently ongoing to evaluate its safety, pharmacokinetics, and clinical efficacy.(Visaria et al 2007; Visaria R, Bischof JC, Loren M, et al. 2007. Nanotherapeutics for enhancing thermal therapy of cancer. Int J Hyperthermia, 23:501–11.), (www.cytimmune.com/download/posters/ASCO_Poster.pdf)

Both TNF-a and thiolated polyethylene glycol (PEG-Thiol) are independently bound to the surface of 27 nm colloidal gold particles.

Clinical Trial Protocol:

Aim: CYT-6091 was tested in a phase I open label trial in solid tumor, advanced stage patients.

Patients (n = 3/dose), admitted to the NIH Clinical Center ICU, received two IV injections of CYT-6091 on day 0 and 14. Dosing started at 50 µg/m2 of TNF, up to 600 µg/m2. Vital signs were monitored and blood samples were drawn over 48 h.

  • The primary endpoint of the study was to determine the MTD for CYT-6091.
  • Secondary endpoints included PK, disease response (staged 45 days post treatment by RECIST), and the detection of gold nanoparticles in tumors and in adjacent healthy tissue.

Results:

  • Twenty-nine patients were treated. Even at the lowest dose (50 µg/m2), patients exhibited a febrile response, which was mitigated by acetaminophen and indomethacin pretreatment. None of the 29 patients treated with doses of 50-600 µg/m2 showed a DLT hypotensive response, and in fact, no DLT was seen.
  • T1/2 estimates for TNF, administered as CYT-6091, are 120, 131, 127, 146, 112, 113, 266, 371, and 160 minutes for 50, 100, 150, 200, 250, 300, 400, 500, 600 µg/m2, respectively (published T1/2 for native TNF is ~27 minutes).
  • In the 28 patients eligible for response assessment, there was 1 PR (100 µg/m2 dose, 7 months duration) and 3 SD (2, 2, and 3 months duration). Electron micrographs show gold nanoparticles in tumor biopsies

Conclusions:

CYT-6091 is well tolerated at doses up to 600 µg/m2 of TNF, levels 3-times greater than the published MTD for native TNF. CYT-6091 targets tumors in humans. Efficacy studies in combination with chemotherapy are planned.

In summary, the phase I clinical trial used solid tumor patients to evaluate the safety of its use, breast cancer oncologists however, set their eyes on the target.

Ref:

1. Jemel. A CA cancer J Clin 2010:60; 277-300

2. Nature Reviews Clinical Oncology to coincide with the 2010 San Antonio Breast Cancer Symposiumhttp://www.nature.com/nrclinonc/focus/breast-cancer/index.html

3. Visaria RK, Griffi n RJ, Williams BW, et al. 2006. Enhancement of tumor thermal therapy using gold nanoparticle-assisted tumor necrosis factoralpha delivery. Mol Cancer Ther, 5:1014–20

4. Visaria R, Bischof JC, Loren M, et al. 2007. Nanotherapeutics for enhancing thermal therapy of cancer. Int J Hyperthermia, 23:501–11.

5. http://nano.gov/sites/default/files/nanomedicine_-_tamarkin.pdf

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Diagnosing Lung Cancer in Exhaled Breath using Gold Nanoparticles

Reporter-curator: Tilda Barliya PhD

Authors: Gang Peng, Ulrike Tisch, Orna Adams1, Meggie Hakim, Nisrean Shehada, Yoav Y. Broza, Salem Billan, Roxolyana Abdah-Bortnyak, Abraham Kuten & Hossam Haick. (NATURE NANOTECHNOLOGY | VOL 4 | OCTOBER 2009 |)

Abstract:

Conventional diagnostic methods for lung cancer1,2 are unsuitable for widespread screening, because they are expensive and occasionally miss tumours. Gas chromatography/mass spectrometry studies have shown that several volatile organic compounds, which normally appear at levels of 1–20 ppb in healthy human breath, are elevated to levels between 10 and 100 ppb in lung cancer patients. Here we show that an array of sensors based on gold nanoparticles can rapidly distinguish the breath of lung cancer patients from the breath of healthy individuals in an atmosphere of high humidity. In combination with solidphase microextraction, gas chromatography/mass spectrometry was used to identify 42 volatile organic compounds that represent lung cancer biomarkers. Four of these were used to train and optimize the sensors, demonstrating good agreement between patient and simulated breath samples. Our results show that sensors based on gold nanoparticles could form the basis of an inexpensive and non-invasive diagnostic tool for lung cancer. (http://www.nature.com/nnano/journal/v4/n10/abs/nnano.2009.235.html) (lnbd.technion.ac.il/NanoChemistry/SendFile.asp?DBID=1…1…) Nanosensors Detect Cancer Breath

Introduction:

Lung cancer accounts for 28% of cancer-related deaths. Approximately 1.3 million people die worldwide every year. Breath testing is a fast, non-invasive diagnostic method that links specific volatile organic compounds (VOCs) in exhaled breath to medical conditions. Gas chromatography/mass spectrometry (GC-MS), ion flow tube mass spectrometry10, laser absorption spectrometry,infrared spectroscopy, polymer-coated surface acoustic wave sensors and coated quartz crystal microbalance sensors have been used for this purpose. However, these techniques are expensive, slow, require complex instruments and, furthermore, require pre-concentration of the biomarkers (that is, treating the biomarkers by a process to increase the relative concentration of the biomarkers to a level that can be detected by the specific technique) to improve detection.

Here, we report a simple, inexpensive, portable sensing technology to distinguish the breath of lung cancer patients from healthy subjects without the need to pre-treat the exhaled breath in any way (see also refs 14–16 for the diagnosis of lung cancer by sensing technology that is based on arrays of polymer/carbon black sensors). Our study consisted of four phases and included volunteers aged 28–60 years. Samples were collected from 56 healthy controls and 40 lung cancer patients after clinical diagnosis using conventional methods and before chemotherapy or other treatment.

In the first phase, we collected exhaled alveolar breath of lung cancer patients and healthy subjects using an ‘offline’ method. This method was designed to avoid potential errors arising from the failure to distinguish endogenous compounds from exogenous ones in the breath and to exclude nasal entrainment of the gas. Exogenous VOCs can be either directly absorbed through the lung via the inhaled breath or indirectly through the blood or skin. Endogenous VOCs are generated by cellular biochemical processes in the body and may provide insight into the body’s function

In the second phase, we identified the VOCs that can serve as biomarkers for lung cancer in the breath samples and determined their relative compositions, using GC-MS in combination with solidphase microextraction (SPME). GC-MS analysis identified over 300–400 different VOCs per breath sample, with .87% reproducibility for a specific volunteer examined multiple times over a period of six months. Forward stepwise discriminant analysis identified 33 common VOCs that appear in at least 83% of the patients but in fewer than 83% of the healthy subjects

The compounds that were observed in both healthy breath and lung cancer breath were presented not only at different concentrations but also in distinctively different mixture compositions.

Further forward stepwise discriminant analysis revealed nine uncommon VOCs that appear in at least 83% of the patients but not in the majority (83%) of healthy subjects. This additional class of VOCs has not been recognized in earlier GC-MS studies.

In spite of these advances in the GC-MS analysis, these data certainly do not account for all the VOCs present in the exhaled breath samples, because the pre-concentration technique can be thought of as a solid phase that extracts only part of the analytes present in the examined phase and, subsequently, releases only part of the extracted analytes.

So, it is likely that the actual mixture of VOCs to which, for example, an array of gold nanoparticle sensors would be responding  is different from that obtained by GC-MS.

In the third phase of this study we designed an array of nine crossreactive chemiresistors, in which each sensor was widely responsive to a variety of odorants for the detection of lung cancer by means of breath testing. We used chemiresistors based on assemblies of 5-nm gold nanoparticles  with different organic functionalities (dodecanethiol, decanethiol, 1-butanethiol, 2-ethylhexanethiol, hexanethiol, tert-dodecanethiol, 4-methoxy-toluenethiol, 2-mercaptobenzoxazole and 11-mercapto-1-undecanol).Diagnosing lung cancer in exhaled breath

Chemiresistors based on functionalized gold nanoparticles combine the advantages of organic specificity with the robustness and processability of inorganic materials.

The response of the nine-sensor array to both healthy and lung cancer breath samples was analysed using principal component analysis . It can be seen that there is no overlap of the lung cancer and healthy patterns.

The PCA of the healthy control group revealed that the set of gold nanoparticles sensors was not influenced by characteristics such as gender, age or smoking habits, thus strengthening the ability of the sensors to discriminate between healthy and cancerous breath. Experiments with a wider population of volunteers to thoroughly probe the influence of diet, alcohol consumption,metabolic state and genetics are under way and will be published elsewhere.

Summary:

To summarize, we have demonstrated that an array of chemiresistors based on functionalized gold nanoparticles in combination with pattern recognition methods can distinguish between the breath of lung cancer patients and healthy controls, without the need for dehumidification or pre-concentration of the lung cancer biomarkers. Our results show great promise for fast, easy and cost-effective diagnosis and screening of lung cancer. The developed devices are expected to be relatively inexpensive, portable and amenable to use in widespread screening, making them potentially valuable in saving millions of lives every year. Given the impact of the rising incidence of cancer on health budgets worldwide, the proposed technology will be a significant saving for both private and public health expenditures. The potential exists for using the proposed technology to diagnose other conditions and diseases, which could mean additional cost reductions and enhanced opportunities to save lives.

Ref:

1. Gang Peng, Ulrike Tisch, Orna Adams, Meggie Hakim, Nisrean Shehada, Yoav Y. Broza, Salem Billan, Roxolyana Abdah-Bortnyak, Abraham Kuten& Hossam Haick. Diagnosing lung cancer in exhaled breath using gold nanoparticles. Nature Nanotechnology 4, 669 – 673 (2009) http://www.nature.com/nnano/journal/v4/n10/abs/nnano.2009.235.html

2. http://lungcancer.about.com/od/diagnosisoflungcancer/a/diagnosislungca.htm

3. http://metabolomx.com/2011/12/15/metabolomx-test-detects-lung-cancer-from-breath/

4. http://www.chestnet.org/accp/pccsu/medical-applications-exhaled-breath-analysis-and-testing?page=0,3

 

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Personalized Medicine: Cancer Cell Biology and Minimally Invasive Surgery (MIS)

Curator: Aviva Lev-Ari, PhD, RN

In the field of Cancer Research, Translational Medicine  will become Personalized Medicine when each of the cancer type, below will have a Genetic Marker allowing the Clinical Team to use the marker for:

  • prediction of Patient’s reaction to Drug induction
  • design of Clinical Trials to validate drug efficacy on small subset of patients predicted to react favorable to drug regimen, increasing validity and reliability
  • Genetical identification of patients at no need to have a drug administered if non sensitivity to the drug has been predicted

Current urgent need exists for Identification of Genetic Markers to predict Patient’s reaction to Drugs Induction for the following types of Cancer:

 

The executive task of the clinician remains to assess the differentiation in Tumor Response to Treatment.

Review of limitations for the current existing Tools used by clinicians in to be found in:

Brücher BLDM, Bilchik A, Nissan A, Avital I & Stojadinovic A. Can tumor response to therapy be predicted, thereby improving the selection of patients for cancer treatment?  Future Oncology 2012; 8(8): 903-906 , DOI 10.2217/fon.12.78 (doi:10.2217/fon.12.78)   The heterogeneity is a problem that will take at least another decade to unravel because of the number of signaling pathways and the crosstalk that is specifically at issue.

Future Oncology August 2012, Vol. 8, No. 8, Pages 903-906 ,

It is suggested that the new modality should be based on individualized histopathology as well as tumor molecular, genetic and functional characteristics, and individual patients’ characteristics. The new modality should be based on empirical evidence that translates into relevant and meaningful clinical outcome data.

Cancer is in particular a difficult to treat tissue type pathology. In “Tumor response criteria: are they appropriate?” that concern is addressed as follows:

“This becomes a conundrum of sorts in an era of ‘minimally invasive treatment’. One frequently encountered example is that of a patient with chronic gastric reflux and an ultrasound-staged T3N1 distal esophageal adenocarcinoma, who had complete sonographic tumor response to neoadjuvant chemoradiation. The physician may declare that, the tumor having disappeared, the patient requires no further treatment. The surgical oncologist recommends resection, recognizing the fact that up to 20% or more of these complete responders will have identifiable nests of tumor beyond the mucosal scar within the specimen – in other words: residual tumor. In other cases, patients with clinical, sonographic, functional (PET) and histopathological ‘complete’ tumor response to induction therapy experience recurrence within the first 2 years of resection, reminding us of the intricacy and enigma of tumor biology. We have yet to develop the tools needed to consistently delineate the response of a tumor to multimodality therapy.”

This described reality in the Oncology Operating Room is coupled with new trends in invasive treatment of tumor resection.

Minimally Invasive Surgery (MIS) vs. conventional surgery dissection applied to cancer tissue with the known pathophysiology of recurrence and remission cycles has its short term advantages. However, in many cases MIS is not the right surgical decision, yet, it is applied for a corollary of patient-centered care considerations. At present, facing the unknown of the future behavior of the tumor as its response to therapeutics bearing uncertainty related to therapy outcomes.

An increase in the desirable outcomes of MIS as a modality of treatment, will be strongly assisted in the future, with anticipated progress to be made in the field of Cancer Research, Translational Medicine and Personalized Medicine, when each of the cancer types, above,  will already have a Genetic Marker allowing the Clinical Team to use the marker(s) for:

  • prediction of Patient’s reaction to Drug induction
  • design of Clinical Trials to validate drug efficacy on small subset of patients predicted to react favorable to drug regimen, increasing validity and reliability
  • Genetical identification of patients at no need to have a drug administered if non sensitivity to the drug has been predicted by the genetic marker.

REFERENCES

Tumor response criteria: are they appropriate?

Björn LDM Brücher*1,2, Anton Bilchik2,3, Aviram Nissan2,4, Itzhak Avital2,5 & Alexander Stojadinovic2,6

 
Treatment for cure is not the endpoint, but the best that can be done is to extend the time of survival to a realistic long term goal and retain a quality of life.
 
Brücher BLDM, Piso P, Verwaal V et al. Peritoneal carcinomatosis: overview and basics. Cancer Invest.30(3),209–224 (2012).
 
Brücher BLDM, Swisher S, Königsrainer A et al. Response to preoperative therapy in upper gastrointestinal cancers. Ann. Surg. Oncol.16(4),878–886 (2009).
 
Miller AB, Hoogstraten B, Staquet M, Winkler A. Reporting results of cancer treatment. Cancer47(1),207–214 (1981).
 
 
 

Other research papers on Cancer and Cancer Therapeutics were published on this Scientific Web site as follows:

What can we expect of tumor therapeutic response?

PIK3CA mutation in Colorectal Cancer may serve as a Predictive Molecular Biomarker for adjuvant Aspirin therapy

Nanotechnology Tackles Brain Cancer

Response to Multiple Cancer Drugs through Regulation of TGF-β Receptor Signaling: a MED12 Control

Personalized medicine-based cure for cancer might not be far away

GSK for Personalized Medicine using Cancer Drugs needs Alacris systems biology model to determine the in silico effect of the inhibitor in its “virtual clinical trial”

Lung Cancer (NSCLC), drug administration and nanotechnology

Non-small Cell Lung Cancer drugs – where does the Future lie?

Cancer Innovations from across the Web

arrayMap: Genomic Feature Mining of Cancer Entities of Copy Number Abnormalities (CNAs) Data

How mobile elements in “Junk” DNA promote cancer. Part 1: Transposon-mediated tumorigenesis.

Cancer Genomics – Leading the Way by Cancer Genomics Program at UC Santa Cruz

Closing the gap towards real-time, imaging-guided treatment of cancer patients.

Closing the gap towards real-time, imaging-guided treatment of cancer patients.

mRNA interference with cancer expression

Search Results for ‘cancer’ on this web site

Cancer Genomics – Leading the Way by Cancer Genomics Program at UC Santa Cruz

Closing the gap towards real-time, imaging-guided treatment of cancer patients.

Lipid Profile, Saturated Fats, Raman Spectrosopy, Cancer Cytology

mRNA interference with cancer expression

Pancreatic cancer genomes: Axon guidance pathway genes – aberrations revealed

Biomarker tool development for Early Diagnosis of Pancreatic Cancer: Van Andel Institute and Emory University

Is the Warburg Effect the cause or the effect of cancer: A 21st Century View?

Crucial role of Nitric Oxide in Cancer

Targeting Glucose Deprived Network Along with Targeted Cancer Therapy Can be a Possible Method of Treatment

 

See comment written for:

Knowing the tumor’s size and location, could we target treatment to THE ROI by applying…..

http://pharmaceuticalintelligence.com/2012/10/16/knowing-the-tumors-size-and-location-could-we-target-treatment-to-the-roi-by-applying-imaging-guided-intervention/

24 Responses

  1. GREAT work.

    I’ll read and comment later on

  2. Highlights of The 2012 Johns Hopkins Prostate Disorders White Paper include:

    A promising new treatment for men with frequent nighttime urination.
    Answers to 8 common questions about sacral nerve stimulation for lower urinary tract symptoms.
    Surprising research on the link between smoking and prostate cancer recurrence.
    How men who drink 6 cups of coffee a day or more may reduce their risk of aggressive prostate cancer.
    Should you have a PSA screening test? Answers to important questions on the controversial USPSTF recommendation.
    Watchful waiting or radical prostatectomy for men with early-stage prostate cancer? What the research suggests.
    A look at state-of-the-art surveillance strategies for men on active surveillance for prostate cancer.
    Locally advanced prostate cancer: Will you benefit from radiation and hormones?
    New drug offers hope for men with metastatic castrate-resistant prostate cancer.
    Behavioral therapy for incontinence: Why it might be worth a try.

    You’ll also get the latest news on benign prostatic enlargement (BPE), also known as benign prostatic hyperplasia (BPH) and prostatitis:
    What’s your Prostate Symptom Score? Here’s a quick quiz you can take right now to determine if you should seek treatment for your enlarged prostate.
    Your surgical choices: a close look at simple prostatectomy, transurethral prostatectomy and open prostatectomy.
    New warnings about 5-alpha-reductase inhibitors and aggressive prostate cancer.

  3. Promising technique.

    INCORE pointed out in detail about the general problem judging response and the stil missing quality in standardization:

    http://www.futuremedicine.com/doi/abs/10.2217/fon.12.78?url_ver=Z39.88-2003&rfr_id=ori:rid:crossref.org&rfr_dat=cr_pub%3dwww.ncbi.nlm.nih.gov

    I did research in response evaluation and prediction for about 15y now and being honest: neither the clinical, nor the molecular biological data proved significant benefit in changing a strategy in patient diagnosis and / or treatment. I would state: this brings us back on the ground and not upon the sky. Additionally it means: we have to ´work harder on that and the WHO has to take responsibility: clinicians use a reponse classification without knowing, that this is just related to “ONE” experiment from the 70′s and that this experiment never had been rescrutinized (please read the Editorial I provided – we use a clinical response classification since more than 30 years worldwide (Miller et al. Cancer 1981) but it is useless !

  4. Dr. BB

    Thank you for your comment.
    Dr. Nir will reply to your comment.
    Regarding the Response Classification in use, it seems that the College of Oncology should champion a task force to revisit the Best Practice in use in this domain and issue a revised version or a new effort for a a new classification system for Clinical Response to treatment in Cancer.

  5. I’m sorry that I was looking for this paper again earlier and didn’t find it. I answered my view on your article earlier.

    This is a method demonstration, but not a proof of concept by any means. It adds to the cacophany of approaches, and in a much larger study would prove to be beneficial in treatment, but not a cure for serious prostate cancer because it is unlikely that it can get beyond the margin, and also because there is overtreatment at the cutoff of PSA at 4.0. There is now a proved prediction model that went to press some 4 months ago. I think that the pathologist has to see the tissue, and the standard in pathology now is for any result that is cancer, two pathologist or a group sitting together should see it. It’s not an easy diagnosis.

    Björn LDM Brücher, Anton Bilchik, Aviram Nissan, Itzhak Avital, & Alexander Stojadinovic. Tumor response criteria: are they appropriate? Future Oncol. (2012) 8(8), 903–906. 10.2217/FON.12.78. ISSN 1479-6694.

    ..Tumor heterogeneity is a ubiquitous phemomenon. In particular, there are important differences among the various types of gastrointestinal (GI) cancers in terms of tumor biology, treatment response and prognosis.

    ..This forms the principal basis for targeted therapy directed by tumor-specific testing at either the gene or protein level. Despite rapid advances in our understanding of targeted therapy for GI cancers, the impact on cancer survival has been marginal.

    ..Can tumor response to therapy be predicted, thereby improving the selection of patients for cancer treatment?

    ..In 2000 theNCI with the European Association for Research and Treatment of Cancer, proposed a replacement of 2D measurement with a decrease in the largest tumor diameter by 30% in one dimension. Tumor response as defined would translate into a 50% decrease for a spherical lesion

    ..We must rethink how we may better determine treatment response in a reliable, reproducible way that is aimed at individualizing the therapy of cancer patients.

    ..we must change the tools we use to assess tumor response. The new modality should be based on empirical evidence that translates into relevant and meaningful clinical outcome data.

    ..This becomes a conundrum of sorts in an era of ‘minimally invasive treatment’.

    ..integrated multidisciplinary panel of international experts – not sure that that will do it

    Several years ago i heard Stamey present the totality of his work at Stanford, with great disappointment over hsPSA that they pioneered in. The outcomes were disappointing.

    I had published a review of all of our cases reviewed for 1 year with Marguerite Pinto.
    There’s a reason that the physicians line up outside of her office for her opinion.
    The review showed that a PSA over 24 ng/ml is predictive of bone metastasis. Any result over 10 was as likely to be prostatitis, BPH or cancer.

    I did an ordinal regression in the next study with Gustave Davis using a bivariate ordinal regression to predict lymph node metastasis using the PSA and the Gleason score. It was better than any univariate model, but there was no followup.

    I reviewed a paper for Clin Biochemistry (Elsevier) on a new method for PSA, very different than what we are familiar with. It was the most elegant paper I have seen in the treatment of the data. The model could predict post procedural time to recurrence to 8 years.

    • I hope we are in agreement on the fact that imaging guided interventions are needed for better treatment outcome. The point I’m trying to make in this post is that people are investing in developing imaging guided intervention and it is making progress.

      Over diagnosis and over treatment is another issue altogether. I think that many of my other posts are dealing with that.

  6. Tumor response criteria: are they appropriate?
    Future Oncology 2012; 8(8): 903-906 , DOI 10.2217/fon.12.78 (doi:10.2217/fon.12.78)
    Björn LDM Brücher, Anton Bilchik, Aviram Nissan, Itzhak Avital & Alexander Stojadinovic
    Tumor heterogeneity is a problematic because of differences among the metabolic variety among types of gastrointestinal (GI) cancers, confounding treatment response and prognosis.
    This is in response to … a group of investigators from Sunnybrook Health Sciences Centre, University of Toronto, Ontario, Canada who evaluate the feasibility and safety of magnetic resonance (MR) imaging–controlled transurethral ultrasound therapy for prostate cancer in humans. Their study’s objective was to prove that using real-time MRI guidance of HIFU treatment is possible and it guarantees that the location of ablated tissue indeed corresponds to the locations planned for treatment.
    1. There is a difference between expected response to esophageal or gastric neoplasms both biologically and in expected response, even given variability within a class. The expected time to recurrence is usually longer in the latter case, but the confounders are – age at time of discovery, biological time of detection, presence of lymph node and/or distant metastasis, microscopic vascular invasion.
    2. There is a long latent period in abdominal cancers before discovery, unless a lesion is found incidentally in surgery for another reason.
    3. The undeniable reality is that it is not difficult to identify the main lesion, but it is difficult to identify adjacent epithelium that is at risk (transitional or pretransitional). Pathologists have a very good idea about precancerous cervical neoplasia.

    The heterogeneity rests within each tumor and between the primary and metastatic sites, which is expected to be improved by targeted therapy directed by tumor-specific testing. Despite rapid advances in our understanding of targeted therapy for GI cancers, the impact on cancer survival has been marginal.

    The heterogeneity is a problem that will take at least another decade to unravel because of the number of signaling pathways and the crosstalk that is specifically at issue.

    I must refer back to the work of Frank Dixon, Herschel Sidransky, and others, who did much to develop a concept of neoplasia occurring in several stages – minimal deviation and fast growing. These have differences in growth rates, anaplasia, and biochemical. This resembles the multiple “hit” theory that is described in “systemic inflammatory” disease leading to a final stage, as in sepsis and septic shock.
    In 1920, Otto Warburg received the Nobel Prize for his work on respiration. He postulated that cancer cells become anaerobic compared with their normal counterpart that uses aerobic respiration to meet most energy needs. He attributed this to “mitochondrial dysfunction. In fact, we now think that in response to oxidative stress, the mitochondrion relies on the Lynen Cycle to make more cells and the major source of energy becomes glycolytic, which is at the expense of the lean body mass (muscle), which produces gluconeogenic precursors from muscle proteolysis (cancer cachexia). There is a loss of about 26 ATP ~Ps in the transition.
    The mitochondrial gene expression system includes the mitochondrial genome, mitochondrial ribosomes, and the transcription and translation machinery needed to regulate and conduct gene expression as well as mtDNA replication and repair. Machinery involved in energetics includes the enzymes of the Kreb’s citric acid or TCA (tricarboxylic acid) cycle, some of the enzymes involved in fatty acid catabolism (β-oxidation), and the proteins needed to help regulate these systems. The inner membrane is central to mitochondrial physiology and, as such, contains multiple protein systems of interest. These include the protein complexes involved in the electron transport component of oxidative phosphorylation and proteins involved in substrate and ion transport.
    Mitochondrial roles in, and effects on, cellular homeostasis extend far beyond the production of ATP, but the transformation of energy is central to most mitochondrial functions. Reducing equivalents are also used for anabolic reactions. The energy produced by mitochondria is most commonly thought of to come from the pyruvate that results from glycolysis, but it is important to keep in mind that the chemical energy contained in both fats and amino acids can also be converted into NADH and FADH2 through mitochondrial pathways. The major mechanism for harvesting energy from fats is β-oxidation; the major mechanism for harvesting energy from amino acids and pyruvate is the TCA cycle. Once the chemical energy has been transformed into NADH and FADH2 (also discovered by Warburg and the basis for a second Nobel nomination in 1934), these compounds are fed into the mitochondrial respiratory chain.
    The hydroxyl free radical is extremely reactive. It will react with most, if not all, compounds found in the living cell (including DNA, proteins, lipids and a host of small molecules). The hydroxyl free radical is so aggressive that it will react within 5 (or so) molecular diameters from its site of production. The damage caused by it, therefore, is very site specific. The reactions of the hydroxyl free radical can be classified as hydrogen abstraction, electron transfer, and addition.
    The formation of the hydroxyl free radical can be disastrous for living organisms. Unlike superoxide and hydrogen peroxide, which are mainly controlled enzymatically, the hydroxyl free radical is far too reactive to be restricted in such a way – it will even attack antioxidant enzymes. Instead, biological defenses have evolved that reduce the chance that the hydroxyl free radical will be produced and, as nothing is perfect, to repair damage.
    Currently, some endogenous markers are being proposed as useful measures of total “oxidative stress” e.g., 8-hydroxy-2’deoxyguanosine in urine. The ideal scavenger must be non-toxic, have limited or no biological activity, readily reach the site of hydroxyl free radical production (i.e., pass through barriers such as the blood-brain barrier), react rapidly with the free radical, be specific for this radical, and neither the scavenger nor its product(s) should undergo further metabolism.
    Nitric oxide has a single unpaired electron in its π*2p antibonding orbital and is therefore paramagnetic. This unpaired electron also weakens the overall bonding seen in diatomic nitrogen molecules so that the nitrogen and oxygen atoms are joined by only 2.5 bonds. The structure of nitric oxide is a resonance hybrid of two forms.
    In living organisms nitric oxide is produced enzymatically. Microbes can generate nitric oxide by the reduction of nitrite or oxidation of ammonia. In mammals nitric oxide is produced by stepwise oxidation of L-arginine catalyzed by nitric oxide synthase (NOS). Nitric oxide is formed from the guanidino nitrogen of the L-arginine in a reaction that consumes five electrons and requires flavin adenine dinucleotide (FAD), flavin mononucleotide (FMN) tetrahydrobiopterin (BH4), and iron protoporphyrin IX as cofactors. The primary product of NOS activity may be the nitroxyl anion that is then converted to nitric oxide by electron acceptors.
    The thiol-disulfide redox couple is very important to oxidative metabolism. GSH is a reducing cofactor for glutathione peroxidase, an antioxidant enzyme responsible for the destruction of hydrogen peroxide. Thiols and disulfides can readily undergo exchange reactions, forming mixed disulfides. Thiol-disulfide exchange is biologically very important. For example, GSH can react with protein cystine groups and influence the correct folding of proteins, and it GSH may play a direct role in cellular signaling through thiol-disulfide exchange reactions with membrane bound receptor proteins (e.g., the insulin receptor complex), transcription factors (e.g., nuclear factor κB), and regulatory proteins in cells. Conditions that alter the redox status of the cell can have important consequences on cellular function.
    So the complexity of life is not yet unraveled.

    Can tumor response to therapy be predicted, thereby improving the selection of patients for cancer treatment?
    The goal is not just complete response. Histopathological response seems to be related post-treatment histopathological assessment but it is not free from the challenge of accurately determining treatment response, as this method cannot delineate whether or not there are residual cancer cells. Functional imaging to assess metabolic response by 18-fluorodeoxyglucose PET also has its limits, as the results are impacted significantly by several variables:

    • tumor type
    • sizing
    • doubling time
    • anaplasia?
    • extent of tumor necrosis
    • type of antitumor therapy and the time when response was determined.
    The new modality should be based on individualized histopathology as well as tumor molecular, genetic and functional characteristics, and individual patients’ characteristics, a greater challenge in an era of ‘minimally invasive treatment’.
    This listing suggests that for every cancer the following data has to be collected (except doubling time). If there are five variables, the classification based on these alone would calculate to be very sizable based on Eugene Rypka’s feature extraction and classification. But looking forward, time to remission and disease free survival are additionally important. Treatment for cure is not the endpoint, but the best that can be done is to extend the time of survival to a realistic long term goal and retain a quality of life.

    Brücher BLDM, Piso P, Verwaal V et al. Peritoneal carcinomatosis: overview and basics. Cancer Invest.30(3),209–224 (2012).
    Brücher BLDM, Swisher S, Königsrainer A et al. Response to preoperative therapy in upper gastrointestinal cancers. Ann. Surg. Oncol.16(4),878–886 (2009).
    Miller AB, Hoogstraten B, Staquet M, Winkler A. Reporting results of cancer treatment. Cancer47(1),207–214 (1981).
    Therasse P, Arbuck SG, Eisenhauer EA et al. New guidelines to evaluate the response to treatment in solid tumors. European Organization for Research and Treatment of Cancer, National Cancer Institute of the United States, National Cancer Institute of Canada. J. Natl Cancer Inst.92(3),205–216 (2000).
    Brücher BLDM, Becker K, Lordick F et al. The clinical impact of histopathological response assessment by residual tumor cell quantification in esophageal squamous cell carcinomas. Cancer106(10),2119–2127 (2006).

    • Dr. Larry,

      Thank you for this comment.

      Please carry it as a stand alone post, Dr. Ritu will refer to it and reference it in her FORTHCOMING pst on Tumor Response which will integrate multiple sources.

      Please execute my instruction

      Thank you

    • Thank you Larry for this educating comment. It explains very well why the Canadian investigators did not try to measure therapy response!

      What they have demonstrated is the technological feasibility of coupling a treatment device to an imaging device and use that in order to guide the treatment to the right place.

      the issue of “choice of treatment” to which you are referring is not in the scope of this publication.
      The point is: if one treatment modality can be guided, other can as well! This should encourage others, to try and develop imaging-based treatment guidance systems.

  7. The crux of the matter in terms of capability is that the cancer tissue, adjacent tissue, and the fibrous matrix are all in transition to the cancerous state. It is taught to resect leaving “free margin”, which is better aesthetically, and has had success in breast surgery. The dilemma is that the patient may return, but how soon?

    • Correct. The philosophy behind lumpectomy is preserving quality of life. It was Prof. Veronesi (IEO) who introduced this method 30 years ago noticing that in the majority of cases, the patient will die from something else before presenting recurrence of breast cancer..

      It is well established that when the resection margins are declared by a pathologist (as good as he/she could be) as “free of cancer”, the probability of recurrence is much lower than otherwise.

  8. Dr. Larry,

    To assist Dr. Ritu, PLEASE carry ALL your comments above into a stand alone post and ADD to it your comment on my post on MIS

    Thank you

  9. Great post! Dr. Nir, can the ultrasound be used in conjunction with PET scanning as well to determine a spatial and functional map of the tumor. With a disease like serous ovarian cancer we typically see an intraperitoneal carcimatosis and it appears that clinicians are wanting to use fluorogenic probes and fiberoptics to visualize the numerous nodules located within the cavity Also is the technique being used mainy for surgery or image guided radiotherapy or can you use this for detecting response to various chemotherapeutics including immunotherapy.

    • Ultrasound can and is actually used in conjunction with PET scanning in many cases. The choice of using ultrasound is always left to the practitioner! Being a non-invasive, low cost procedure makes the use of ultrasound a non-issue. The down-side is that because it is so easy to access and operate, nobody bothers to develop rigorous guidelines about using it and the benefits remains the property of individuals.

      In regards to the possibility of screening for ovarian cancer and characterising pelvic masses using ultrasound I can refer you to scientific work in which I was involved:

      1. VAES (E.), MANCHANDA (R), AUTIER, NIR (R), NIR (D.), BLEIBERG (H.), ROBERT (A.), MENON (U.). Differential diagnosis of adnexal masses: Sequential use of the Risk of Malignancy Index and a novel computer aided diagnostic tool. Published in Ultrasound in Obstetrics & Gynecology. Issue 1 (January). Vol. 39. Page(s): 91-98.

      2. VAES (E.), MANCHANDA (R), NIR (R), NIR (D.), BLEIBERG (H.), AUTIER (P.), MENON (U.), ROBERT (A.). Mathematical models to discriminate between benign and malignant adnexal masses: potential diagnostic improvement using Ovarian HistoScanning. Published in International Journal of Gynecologic Cancer (IJGC). Issue 1. Vol. 21. Page(s): 35-43.

      3. LUCIDARME (0.), AKAKPO (J.-P.), GRANBERG (S.), SIDERI (M.), LEVAVI (H.), SCHNEIDER (A.), AUTIER (P.), NIR (D.), BLEIBERG (H.). A new computer aided diagnostic tool for non-invasive characterisation of malignant ovarian masses: Results of a multicentre validation study. Published in European Radiology. Issue 8. Vol. 20. Page(s): 1822-1830.

      Dror Nir, PhD
      Managing partner

      BE: +32 (0) 473 981896
      UK: +44 (0) 2032392424

      web: http://www.radbee.com/
      blogs: http://radbee.wordpress.com/ ; http://www.MedDevOnIce.com

  10. totally true and i am very thankfull for these briliant comments.

    Remember: 10years ago: every cancer researcher stated: “look at the tumor cells only – forget the stroma”. The era of laser-captured tumor-cell dissection started. Now , everyone knows: it is a system we are looking at and viewing and analyzing tumor cells only is really not enough.

    So if we would be honest, we would have to declare, that all data, which had been produced 13-8years ago, dealing with laser capture microdissection, that al these data would need a re-scrutinization, cause the influence of the stroma was “forgotten”. I ‘d better not try thinking about the waisted millions of dollars.

    If we keep on being honest: the surgeon looks at the “free margin” in a kind of reductionable model, the pathologist is more the control instance. I personally see the pathologist as “the control instance” of surgical quality. Therefore, not the wish of the surgeon is important, the objective way of looking into problems or challenges. Can a pathologist always state, if a R0-resection had been performed ?

    The use of the Resectability Classification:
    There had been many many surrogate marker analysis – nothing new. BUT never a real substantial well tought through structured analysis had been done: mm by mm by mm by mm and afterwards analyzing that by a ROC analysis. BUt against which goldstandard ? If you perform statistically a ROC analysis – you need a golstandard to compare to. Therefore what is the real R0-resectiòn? It had been not proven. It just had been stated in this or that tumor entity that this or that margin with this margin free mm distance or that mm distance is enough and it had been declared as “the real R0-classification”. In some organs it is very very difficult and we all (surgeons, pathologists, clinicians) that we always get to the limit, if we try interpretating the R-classification within the 3rd dimension. Often it is just declared and stated.

    Otherwise: if lymph nodes are negative it does not mean, lymph nodes are really negative, cause up to 38% for example in upper GI cancers have histological negative lymph nodes, but immunohistochemical positive lymph nodes. And this had been also shown by Stojadinovic at el analyzing the ultrastaging in colorectal cancer. So the 4th dimension of cancer – the lymph nodes / the lymphatic vessel invasion are much more important than just a TNM classification, which unfortunately does often not reflect real tumor biology.

    AS we see: cancer has multifactorial reasons and it is necessary taking the challenge performing high sophisticated research by a multifactorial and multidisciplinary manner.

    Again my deep and heartly thanks for that productive and excellent discussion !

    • Dr. BB,

      Thank you for your comment.

      Multidisciplinary perspectives have illuminated the discussion on the pages of this Journal.

      Eager to review Dr. Ritu’s forthcoming paper – the topic has a life of its own and is embodied in your statement:

      “the 4th dimension of cancer – the lymph nodes / the lymphatic vessel invasion are much more important than just a TNM classification, which unfortunately does often not reflect real tumor biology.”

    • Thank you BB for your comment. You have touched the core limitation of healthcare professionals: how do we know that we know!

      Do we have a reference to each of the test we perform?

      Do we have objective and standardise quality measures?

      Do we see what is out-there or are we imagining?

      The good news: Everyday we can “think” that we learned something new. We should be happy with that, even if it is means that we learned that yesterday’s truth is not true any-more and even if we are likely to be wrong again…:)

      But still, in the last decades, lots of progress was made….

  11. Dr. Nir,
    I thoroughly enjoyed reading your post as well as the comments that your post has attracted. There were different points of view and each one has been supported with relevant examples in the literature. Here are my two cents on the discussion:
    The paper that you have discussed had the objective of finding out whether real-time MRI guidance of treatment was even possible and if yes, and also if the treatment could be performed in accurate location of the ROI? The data reveals they were pretty successful in accomplishing their objective and of course that gives hope to the imaging-based targeted therapies.
    Whether the ROI is defined properly and if it accounts for the real tumor cure, is a different question. Role of pathologists and the histological analysis they bring about to the table cannot be ruled out, and the absence of a defined line between the tumor and the stromal region in the vicinity is well documented. However, that cannot rule out the value and scope of imaging-based detection and targeted therapy. After all, it is seminal in guiding minimally invasive surgery. As another arm of personalized medicine-based cure for cancer, molecular biologists at MD Anderson have suggested molecular and genetic profiling of the tumor to determine genetic aberrations on the basis of which matched-therapy could be recommended to patients. When phase I trial was conducted, the results were obtained were encouraging and the survival rate was better in matched-therapy patients compared to unmatched patients. Therefore, everytime there is more to consider when treating a cancer patient and who knows a combination of views of oncologists, pathologists, molecular biologists, geneticists, surgeons would device improvised protocols for diagnosis and treatment. It is always going to be complicated and generalizations would never give an answer. Smart interpretations of therapies – imaging-based or others would always be required!

    Ritu

    • Dr. Nir,
      One of your earlier comments, mentioned the non invasiveness of ultrasound, thus, it’s prevalence in use for diagnosis.

      This may be true for other or all areas with the exception of Mammography screening. In this field, an ultrasound is performed only if a suspected area of calcification or a lump has been detected in the routine or patient-initiated request for ad hoc mammography secondery to patient complain of pain or patient report of suspected lump.

      Ultrasound in this field repserents ascalation and two radiologists review.

      It in routine use for Breast biopsy.

    • Thanks Ritu for this supporting comment. The worst enemy of finding solutions is doing nothing while using the excuse of looking for the “ultimate solution” . Personally, I believe in combining methods and improving clinical assessment based on information fusion. Being able to predict, and then timely track the response to treatment is a major issue that affects survival and costs!

Judging the ‘Tumor response’-there is more food for thought

http://pharmaceuticalintelligence.com/2012/12/04/judging-the-tumor-response-there-is-more-food-for-thought/

13 Responses

  1. Dr. Sanexa
    you have brought up an interesting and very clinically relevant point: what is the best measurement of response and 2) how perspectives among oncologists and other professionals differ on this issues given their expertise in their respective subspecialties (immunologist versus oncologist. The advent of functional measurements of tumors (PET etc.) seems extremely important in the therapeutic use AND in the development of these types of compounds since usually a response presents (in cases of solid tumors) as either a lack of growth of the tumor or tumor shrinkage. Did the authors include an in-depth discussion of the rapidity of onset of resistance with these types of compounds?
    Thanks for the posting.

  2. Dr. Williams,
    Thanks for your comment on the post. The editorial brings to attention a view that although PET and other imaging methods provide vital information on tumor growth, shrinkage in response to a therapy, however, there are more aspects to consider including genetic and molecular characteristics of tumor.
    It was an editorial review and the authors did not include any in-depth discussion on the rapidity of onset of resistance with these types of compounds as the focus was primarily on interpreting tumor response.
    I am glad you found the contents of the write-up informative.
    Thanks again!
    Ritu

  3. Thank you for your wonderful comment and interpretation. Dr.Sanexa made a brilliant comment.

    May I allow myself putting my finger deeper into this wound ? Cancer patients deserve it.

    It had been already pointed out by international experts from Munich, Tokyo, Hong-Kong and Houston, dealing with upper GI cancer, that the actual response criteria are not appropriate and moreover: the clinical response criteria in use seem rather to function as an alibi, than helping to differentiate and / or discriminate tumor biology (Ann Surg Oncol 2009):

    http://www.ncbi.nlm.nih.gov/pubmed/19194759

    The response data in a phase-II-trial (one tumor entity, one histology, one treatment, one group) revealed: clinical response evaluation according to the WHO-criteria is not appropriate to determine response:

    http://www.ncbi.nlm.nih.gov/pubmed/15498642

    Of course, there was a time, when it seemed to be useful and this also has to be respected.

    There is another challenge: using statistically a ROC and resulting in thresholds. This was, is and always be “a clinical decision only” and not the decision of the statistician. The clinician tells the statistician, what decision, he wants to make – the responsibility is enormous. Getting back to the roots:
    After the main results of the Munich-group had been published 2001 (Ann Surg) and 2004 (J Clin Oncol):

    http://www.ncbi.nlm.nih.gov/pubmed/11224616

    http://www.ncbi.nlm.nih.gov/pubmed/14990646

    the first reaction in the community was: to difficult, can’t be, not re-evaluated, etc.. However, all evaluated cut-offs / thresholds had been later proven to be the real and best ones by the MD Anderson Cancer Center in Houston, Texas. Jaffer Ajani – a great and critical oncologist – pushed that together with Steve Swisher and they found the same results. Than the upper GI stakeholders went an uncommon way in science: they re-scrutinized their findings. Meanwhile the Goldstandard using histopathology as the basis-criterion had been published in Cancer 2006.

    http://www.ncbi.nlm.nih.gov/pubmed/16607651

    Not every author, who was at the authorlist in 2001 and 2004 wanted to be a part of this analysis and publication ! Why ? Everyone should judge that by himself.

    The data of this analysis had been submitted to the New England Journal of Medicine. In the 2nd review stage process, the manuscript was rejected. The Ann Surg Oncol accepted the publication: the re-scrutinized data resulted in another interesting finding: in the future maybe “one PET-scan” might be appropriate predicting the patient’s response.

    Where are we now ?

    The level of evidence using the response criteria is very low: Miller’s (Cancer 1981) publication belonged to ”one single” experiment from Moertel (Cancer 1976). During that time, there was no definition of “experiences” rather than “oncologists”. These terms had not been in use during that time.

    Additionally they resulted in a (scientifically weak) change of the classification, published by Therasse (J Natl Cancer Inst 2000). Targeted therapy did not result in a change so far. In 2009, the international upper GI experts sent their publication of the Ann Surg Oncol 2009 to the WHO but without any kind of reaction.

    Using molecular biological predictive markers within the last 10years all seem to have potential.

    http://www.ncbi.nlm.nih.gov/pubmed/20012971

    http://www.ncbi.nlm.nih.gov/pubmed/18704459

    http://www.ncbi.nlm.nih.gov/pubmed/17940507

    http://www.ncbi.nlm.nih.gov/pubmed/17354029

    But, experts are aware: the real step breaking barriers had not been performed so far. Additionally, it is very important in trying to evaluate and / predict response, that not different tumor entities with different survival and tumor biology are mixed together. Those data are from my perspective not helpful, but maybe that is my own Bias (!) of my view.

    INCORE, the International Consortium of Research Excellence of the Theodor-Billroth-Academy, was invited publishing the Editorial in Future Oncology 2012. The consortium pointed out, that living within an area of ‘prove of principle’ and also trying to work out level of evidence in medicine, it is “the duty and responsibility” of every clinician, but also of the societies and institutions, also of the WHO.

    Complete remission is not the only goal, as experts dealing with ‘response-research’ are aware. It is so frustrating for patients and clinicians: there is a rate of those patients with complete remission, who develop early recurrence ! This reflects, that complete remission cannot function as the only criterion describing response !

    Again, my heartly thanks, that Dr.Sanexa discussed this issue in detail.
    I hope, I found the way explaining the way of development and evaluating response criteria properly and in a differentiated way of view. From the perspective of INCORE:

    “an interdisciplinary initiative with all key stake¬holders and disciplines represented is imperative to make predictive and prognostic individualized tumor response assessment a modern-day reality. The integrated multidisciplinary panel of international experts need to define how to leverage existing data, tissue and testing platforms in order to predict individual patient treatment response and prognosis.”

  4. Dr. Brucher,

    First of all thanks for expressing your views on the ‘tumor response’ in a comprehensive way. You are the first author of the editorial review one of the prominent people who has taken part in the process of defining tumor response and I am glad that you decided to write a comment on the writeup.
    The topic has been explained well in an immaculate manner and that it further clarifies the need for the perfect markers that would be able to evaluate and predict tumor response. There are, as you mentioned, some molecular markers available including VEGF, cyclins, that have been brought to focus in the context of squamous cell carcinoma.

    It would be great if you could be the guest author for our blog and we could publish your opinion (comment on this blog post) as a separate post. Please let us know if it is OK with you.

    Thanks again for your comment
    Ritu

  5. Thank you all to the compelling discussions, above.

    Please review the two sources on the topic I placed at the bottom of the post, above as post on this Scientific Journal,

    All comments made to both entries are part of thisvdiscussion, I am referring to Dr. Nir’s post on size of tumor, to BB comment to Nir’s post, to Larry’ Pathologist view on Tumors and my post on remission and minimally invasive surgery (MIS).

    Great comments by Dr. Williams, BB and wonderful topic exposition by Dr. Ritu.

  6. Aviva,
    Thats a great idea. I will combine all sources referred by you, the post on tumor imaging by Dr. Nir and the comments made on the these posts including Dr. Brucher’s comments in a new posts.
    Thanks
    Ritu

    • Great idea, ask Larry, he has written two very long important comments on this topic, one on Nir’s post and another one, ask him where, if it is not on MIS post. GREAT work, Ritu, integration is very important. Dr, Williams is one of our Gems.

    • Assessing tumour response it is not an easy task!Because tumours don’t change,but happilly our knowlege(about them) does really change,is everchanging(thans god!).In the past we had the Recist Criteria,then the Modified Recist Criteria,becausa of Gist and other tumors.At this very moment,these are clearly insuficient.We do need more ,new validated facing the reality of nowadays.A great,enormoust post Dr Ritu!Congratulations!

 

 

 

 

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Histone Deacetylase Inhibitors Induce Epithelial-to-Mesenchymal Transition in Prostate Cancer Cells(1)

Screen Shot 2021-07-19 at 7.44.44 PM

Word Cloud By Danielle Smolyar

Authors: Dejuan Kong, Aamir Ahmad, Bin Bao, Yiwei Li, Sanjeev Banarjee, Fazlul H. Sarkar, Wayne State University School of Medicine

Reporter-Curator: Stephen J. Williams, Ph.D.

Clinically, there has not been much success in treating solid tumors with histone deacetylase inhibitors (HDACi). Histone acetylation and deacetylation play an important role in transcriptional regulation of genes and increased activity is associated with many cancers, therefore it was thought that HDAC inhibition might be fruitful as a therapy.  There have been several phase I and II clinical trials using HDACi for treatment of various malignancies, including hematological and solid malignancies(2), with most success seen in hematologic malignancies such as cutaneous T-cell lymphoma and peripheral T-cell lymphoma and little or no positive outcome with solid tumors.  Many mechanisms of resistance to HDACi in solid tumors have been described, most of which are seen with other chemotherapeutics such as increased multidrug resistance gene MDR1, increased anti-apoptotic proteins and activation of cell survival pathways(3).

A report in PLOS One by Dr. Dejuan Kong, Dr. Fazlul Sarkar, and colleagues from Wayne State University School of Medicine, demonstrate another possible mechanism of resistance to HDACi in prostate cancer, by induction of the epithelial-to-mesenchymal transition (EMT), which has been associated with the development of resistance to chemotherapies in other malignancies of epithelial origin(4,5).

EMT is an important differentiation process in embryogenesis and felt to be important in progression of cancer.  Epithelial cells will acquire a mesenchymal morphology (on plastic this looks like a cuboidal epithelial cell gaining a more flattened, elongated, tri-corner morphology; see paper Figure 1) and down-regulate epithelial markers such as cytokeratin, up-regulation of mesenchymal markers, increased migration and invasiveness in standard assays, and increased resistance to chemotherapeutics, and similarity to cancer stem cells(6-10).

ImageFigure 1. HDACis led to the induction of EMT phemotype. (A and B) PC3 cells treated with TSA and SAHA for 24 h at indicated doses.  The photomicrographs of PC3 cells treated with TSA and SAHA exhibited a fibroblastic-type phenotype, while cells treated with DMAO control displayed rounded epithelial cell morphology (original magnification, x 100). (C) Treated PC3 cells show increased mesenchymal markers vimentin and ZEB1 and F-actin reorganization.  Figure taken from Kong, D., Ahmad, A., Bao, B., Li, Y., Banerjee, S., and Sarkar, F. H. (2012) PloS one 7, e45045

In this study the authors found that treatment of prostate carcinoma cells with two different HDACis (trichostatin A (TSA) and suberoylanilide hydroxamic acid (SAHA)) induced EMT phenotype mediated through up-regulation of transcription factors ZEB1, ZEB2 and Slug, increased expression of mesenchymal markers vimentin, N-cadherin and fibronectin by promoting histone 3 acetylation on gene promoters.  In addition TSA increased the stem cell markers Sox2 and Nanog with concomitant EMT morphology and increased cell motility.

Below is the abstract of this paper(1):

ABSTRACT

Clinical experience of histone deacetylase inhibitors (HDACIs) in patients with solid tumors has been disappointing; however, the molecular mechanism of treatment failure is not known. Therefore, we sought to investigate the molecular mechanism of treatment failure of HDACIs in the present study. We found that HDACIs Trichostatin A (TSA) and Suberoylanilide hydroxamic acid (SAHA) could induce epithelial-to-mesenchymal transition (EMT) phenotype in prostate cancer (PCa) cells, which was associated with changes in cellular morphology consistent with increased expression of transcription factors ZEB1, ZEB2 and Slug, and mesenchymal markers such as vimentin, N-cadherin and Fibronectin. CHIP assay showed acetylation of histone 3 on proximal promoters of selected genes, which was in part responsible for increased expression of EMT markers. Moreover, TSA treatment led to further increase in the expression of Sox2 and Nanog in PCa cells with EMT phenotype, which was associated with cancer stem-like cell (CSLC) characteristics consistent with increased cell motility. Our results suggest that HDACIs alone would lead to tumor aggressiveness, and thus strategies for reverting EMT-phenotype to mesenchymal-to-epithelial transition (MET) phenotype or the reversal of CSLC characteristics prior to the use of HDACIs would be beneficial to realize the value of HDACIs for the treatment of solid tumors especially PCa.

Highlights of the research include:

  • TSA and SAHA induce morphologic changes  in prostate carcinoma LNCaP and PC3 cells related to EMT by microscopy as well as accumulation of mesenchymal markers ZEB1, vimentin, and F-actin reorganization shown by immunofluorescence microscopy and increased expression of these markers shown by real-time PCR
  • Western blotting showed TSA treatment resulted in hyperacetyulation of histone 3 whi8le CHIP analysis revealed increased histone 3 acetylation on the promoters of vimentin, ZEB2, Slug, and MMP2
  • Western analysis revealed that HDACi not only induced EMT but increased the expression of cancer stem cell markers associated with increased motility such as Sox2 and Nanog.  Increased cell migration was measured by Transwell migration assays and increased cell motility was measured via cell detachment assays

1.            Kong, D., Ahmad, A., Bao, B., Li, Y., Banerjee, S., and Sarkar, F. H. (2012) PloS one 7, e45045

2.            Bertino, E. M., and Otterson, G. A. (2011) Expert opinion on investigational drugs 20, 1151-1158

3.            Robey, R. W., Chakraborty, A. R., Basseville, A., Luchenko, V., Bahr, J., Zhan, Z., and Bates, S. E. (2011) Molecular pharmaceutics 8, 2021-2031

4.            Wang, Z., Li, Y., Kong, D., Banerjee, S., Ahmad, A., Azmi, A. S., Ali, S., Abbruzzese, J. L., Gallick, G. E., and Sarkar, F. H. (2009) Cancer research 69, 2400-2407

5.            Wang, Z., Li, Y., Ahmad, A., Azmi, A. S., Kong, D., Banerjee, S., and Sarkar, F. H. (2010) Drug resistance updates : reviews and commentaries in antimicrobial and anticancer chemotherapy 13, 109-118

6.            Hugo, H., Ackland, M. L., Blick, T., Lawrence, M. G., Clements, J. A., Williams, E. D., and Thompson, E. W. (2007) Journal of cellular physiology 213, 374-383

7.            Thiery, J. P. (2002) Nature reviews. Cancer 2, 442-454

8.            Kong, D., Banerjee, S., Ahmad, A., Li, Y., Wang, Z., Sethi, S., and Sarkar, F. H. (2010) PloS one 5, e12445

9.            Kong, D., Li, Y., Wang, Z., and Sarkar, F. H. (2011) Cancers 3, 716-729

10.          Bao, B., Wang, Z., Ali, S., Kong, D., Li, Y., Ahmad, A., Banerjee, S., Azmi, A. S., Miele, L., and Sarkar, F. H. (2011) Cancer letters 307, 26-36

Other research papers on Cancer and Cancer Therapeutics were published on this Scientific Web site as follows:

PIK3CA mutation in Colorectal Cancer may serve as a Predictive Molecular Biomarker for adjuvant Aspirin therapy

Nanotechnology Tackles Brain Cancer

Response to Multiple Cancer Drugs through Regulation of TGF-β Receptor Signaling: a MED12 Control

Personalized medicine-based cure for cancer might not be far away

GSK for Personalized Medicine using Cancer Drugs needs Alacris systems biology model to determine the in silico effect of the inhibitor in its “virtual clinical trial”

Lung Cancer (NSCLC), drug administration and nanotechnology

Non-small Cell Lung Cancer drugs – where does the Future lie?

Cancer Innovations from across the Web

arrayMap: Genomic Feature Mining of Cancer Entities of Copy Number Abnormalities (CNAs) Data

How mobile elements in “Junk” DNA promote cancer. Part 1: Transposon-mediated tumorigenesis.

Cancer Genomics – Leading the Way by Cancer Genomics Program at UC Santa Cruz

Closing the gap towards real-time, imaging-guided treatment of cancer patients.

Closing the gap towards real-time, imaging-guided treatment of cancer patients.

mRNA interference with cancer expression

Search Results for ‘cancer’ on this web site

Cancer Genomics – Leading the Way by Cancer Genomics Program at UC Santa Cruz

Closing the gap towards real-time, imaging-guided treatment of cancer patients.

Lipid Profile, Saturated Fats, Raman Spectrosopy, Cancer Cytology

mRNA interference with cancer expression

Pancreatic cancer genomes: Axon guidance pathway genes – aberrations revealed

Biomarker tool development for Early Diagnosis of Pancreatic Cancer: Van Andel Institute and Emory University

Is the Warburg Effect the cause or the effect of cancer: A 21st Century View?

Crucial role of Nitric Oxide in Cancer

Targeting Glucose Deprived Network Along with Targeted Cancer Therapy Can be a Possible Method of Treatment

Read Full Post »

 Reporter: Aviva Lev-Ari, PhD, RN

Ernst & Young (“E&Y”) has published their fifth annual report on the state of the medical technology industry.

Below are the link to this report and also a link to an excerpt from the report displaying charts of the industry’s performance.

Definition of the Global Medical Technology Industry

In this report, medical technology (medtech) companies are defined as companies that primarily design and manufacture medical

technology equipment and supplies and are headquartered within the United States or Europe. For the purposes of this report, we have placed Israel’s data and analysis within the European market, and any grouping of the US and Europe has been referred to as “global.”

This wide ranging definition includes medical device, diagnostic, drug delivery and analytical/life science tool companies, but excludes distributors and service providers such as contract research organizations or contract manufacturing organizations.

By any measure, medical technology is an extraordinarily diverse industry. While developing a consistent and meaningful classification system is important, it is anything but straightforward. Existing taxonomies sometimes segregate companies into scores of thinly populated categories, making it difficult to identify and analyze industry trends.

Furthermore, they tend to combine categories based on products (such as imaging or tools) with those based on diseases targeted by those products (such as cardiovascular or oncology), which makes it harder to analyze trends consistently across either dimension. To address some of these challenges, we have categorized medtech companies across both dimensions —products and diseases targeted.

All publicly traded medtech companies were classified as belonging to one of five broad product groups:

Imaging:

companies developing products used to diagnose or monitor conditions via imaging technologies, including products such as MRI machines, computed tomography (CT) and X-ray imaging and optical biopsy systems

Non-imaging diagnostics:

companies developing products used to diagnose or monitor conditions via non-imaging technologies, which can include patient monitoring and in vitro testing equipment

Research and other equipment:

companies developing equipment used for research or other purposes, including analytical and life science tools, specialized laboratory equipment and furniture

Therapeutic devices:

companies developing products used to treat patients, including therapeutic medical devices, tools or drug delivery/infusion technologies

Other:

companies developing products that do not fi t in any of the above categories were classifi ed in this segment

In addition to product groups, this report tracks conglomerate companies that derive a significant part of their revenues from medical technologies. While a conglomerate medtech division’s technology could technically fall into one of the product groups listed above (e.g., General Electric into “imaging” and Allergan into “therapeutic devices”), all conglomerate data is kept separate from that of the nonconglomerates.

This is due to the fact that, while conglomerates report revenues for their medtech divisions, they typically do not report other financial results for their medtech divisions, such as research and development or net income.

Conglomerate companies:

United States

3M Health Care

Abbott: Medical Products

Agilent Technologies: Life Sciences and Chemical Analysis

Allergan: Medical Devices

Baxter International: Medical Products

Corning: Life Sciences

Danaher: Life Sciences & Diagnostics

Endo Health Solutions: AMS and HealthTronics

GE Healthcare

Hospira: Devices

IDEX: Health & Science Technologies

Johnson & Johnson: Medical Devices & Diagnostics

Kimberly-Clark: Health Care

Pall: Life Sciences

Europe

Agfa HealthCare

Bayer HealthCare: Medical Care

Beiersdorf: Hansaplast

Carl Zeiss Meditec

Dräger: Medical

Eckert & Ziegler: Medizintechnik

Fresenius Kabi

Halma: Health and Analysis

Jenoptik: Medical

Novartis: Alcon

Philips Healthcare

Quantel Medical

Roche Diagnostics

Sanofi : Genzyme Biosurgery

SCA Svenska Cellulosa Aktiebolaget: Personal Care

Sempermed

Siemens Healthcare

Smiths Medical

The big picture

Despite lingering financial and regulatory uncertainties, US and European publicly held medtech companies delivered another strong performance in 2011. For both conglomerates and pure-play companies, revenue growth in 2011 outpaced 2010 growth rates. Net income increased by 14% — the third consecutive year of double digit growth, and certainly impressive in today’s challenging economic climate.

So far, the medical technology industry appears to be weathering a period of slower global economic growth. However, for an industry that was accustomed to double-digit revenue growth, considerable margins and a predictable sales-and regulatory environment, the long-term future may still be turbulent. The industry’s financial performance will likely continue to be challenged by low economic growth in developed markets, the prospect of austerity measures in many countries, a looming Eurozone debt crisis and an imminent 2.3% medical device tax in the US. And while the US Supreme Court’s upholding of the Affordable Care Act has removed some of the uncertainty in the US, the regulatory environment continues to grow ever more complex around the globe.

As payers tackle runaway health care costs, medtech will face rising pricing pressures and expanded use of comparative effectiveness — making organic growth in western markets more challenging. Efforts to heighten disease management and preventive care, and other efforts to drive efficiency within the health care system, may impact both product utilization and profitability. The cost of not adapting the traditional medtech business model to stay ahead of these trends could be disastrous.

Public company data 2011                 2010 % change

Revenues $331.7                                          $313.9 6%

Conglomerates $142.3                                $132.8 7%

Pure-play companies $189.4                     $181.0 5%

R&D expense $12.6                                        $12.1 4%

SG&A expense $60.3                                    $57.4 5%

Net income $19.9                                          $17.4 14%

Cash and cash equivalents and short-term investments $39.2      $39.4 -1%

Market capitalization $436.1                                                              $465.9 -6%

Number of employees 725,900                                                           702,200 3%

Number of public companies 411                                                        423 -3%

Source: Ernst & Young and company financial statement data.

Numbers may appear to be inconsistent due to rounding.

Data shown for US and European public companies.

Market capitalization data is shown for 30 June 2011 and 30 June 2012.

Medical technology at a glance, 2010–2011

(US$b, data for pure-play companies except where indicated)

Medtech companies — long known for innovation, reinvention and risk-taking in product development — will need to apply the same principles to business model development. These trends and implications are discussed more fully in this year’s point of view article.

US and European publicly held medtech companies delivered another strong performance in 2011

Since we first published Pulse of the industry back in 2008 (using 2007 figures), a number of medtech firms have seen their revenues grow significantly. It is notable that 6 of the 10 fastest-growing companies over the period 2007–11 — led by spinal device company NuVasive and Intuitive Surgical (maker of the da Vinci Surgical System) — expanded their top lines mostly through organic growth and without the assistance of sizeable mergers or acquisitions. Corning Life Sciences was the only conglomerate to make the top 10 list.

Selected fast-growing US medtechs by revenue growth, 2007–2011

(US$m)

Companies 2007                          2011 CAGR

NuVasive $154                                 $541 37%

Alere $767                                       $2,387 33%

Life Technologies $1,282             $3,776 31%

Intuitive Surgical $601                 $1,757 31%

Illumina $367                                 $1,056 30%

Hologic $738                                   $1,789 25%

Corning Life Sciences $305            $595 18%

Thoratec $235                                   $423 16%

Greatbatch $319                                $569 16%

ResMed $716                                    $1,243 15%

Source: Ernst & Young and company financial statement data.

Companies in italics have made significant acquisitions between 2007 and 2011.

CAGR= Compounded Annual Growth Rate. 6 of the 10 fastest-growing companies expanded their top lines mostly through organic growth

Selected fast-growing European medtechs by revenue growth, 2007–2011

(US$m)

Source: Ernst & Young and company financial statement data.

Companies in italics have made significant acquisitions between 2007 and 2011.

CAGR= Compounded Annual Growth Rate.

Companies        Location          2007                   2011                CAGR

Fresenius Kabi        Germany        $2,782                $5,515                     19%

Sonova Holding      Switzerland      $926                 $1,827                   19%

ELEKTA                   Sweden              $674                 $1,217                    16%

Qiagen                     Netherlands       $650               $1,170                    16%

Stratec Biomedical Systems Germany $94               $165                     15%

Sempermed             Austria               $300                 $517                      15%

Syneron Medical         Israel               $141                  $228                    13%

Given Imaging             Israel               $113                  $178                     12%

William Demant Holding Denmark $1,010             $1,501                    10%

Essilor International France            $3,986               $5,829                  10%

While the fastest-growing companies in the US were fueled largely by organic growth, the four fastest-growing firms in Europe were aided by significant acquisitions. Germany’s Fresenius Kabi holds the distinction of having the biggest expansion in both real dollar and percentage terms on this list.

The company’s growth was in large part fueled by the addition of APP Pharmaceuticals, which it acquired for US$3.7 billion in 2008. Of the six commercial leaders on this list, five had made sizeable purchases, while the smaller “other” companies grew mostly through organic means.

Future Growth

Fueling future growth Mergers & acquisitions

The big picture

Merger and acquisition (M&A) activity among US and European medical technology companies remained vibrant in the year ended June 30, 2012. While 2011–12’s total of US$35.0 billion was well below the levels seen over the last two years, those two years were driven by megadeals done by Novartis (which paid US$41.2 billion to Nestlé for the remaining 75% of Alcon it didn’t already control) and Johnson & Johnson (which paid US$19.7 billion for Synthes). On a normalized basis (after removing the impact of the aforementioned megadeals), 2011–12’s total deal value was more in line with previous years — 25% below the prior year and 16% above the year before that.

Although no megadeals were consummated in 2011–12, there were eight transactions valued at more than US$1 billion, versus 12 the year before. The year’s largest deal was between private equity firm Apax Partners, two Canadian pension funds and Texas-based wound care company Kinetic Concepts Inc. (KCI). The US$6.3 billion Apax/KCI deal was particularly notable, as the US$6.3 billion represented one of the largest leveraged buyouts — across all industries — since the onset of the financial crisis in 2008. Two other private equity firms were also involved in multibillion-dollar M&As: Cinven sold off Swedish diagnostics company Phadia to Thermo Fisher Scientific for US$3.5 billion, and TPG Capital acquired in vitro diagnostics maker Immucor for nearly US$2 billion.

SOURCES:

Pulse of the Industry – Ernst & Young

http://www.ey.com/Publication/vwLUAssets/Pulse_medical_technology_report_2012/$FILE/Pulse_medical_technology_report_2012.pdf

Pulse of the Industry: Medical Technology Report 2012 – Industry performance

http://www.ey.com/GL/en/Industries/Life-Sciences/Pulse–medical-technology-report-2012—Mergers-and-acquisitions—medtechdata 

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Author: Tilda Barliya PhD

In response to the previous post:

Paclitaxel vs Abraxane (albumin-bound paclitaxel)

http://pharmaceuticalintelligence.com/2012/11/17/paclitaxel-vs-abraxane-albumin-bound-paclitaxel/

Pharmacogenomics properties are presented, below.

Paclitaxel is a mitotic inhibitor used in cancer chemotherapy. It was discovered in a U.S. National Cancer Institute program at the Research Triangle Institute (North Carolina)  in 1967 when Monroe E.Wall and Mansukh C.Wani  isolated it from the bark of the Pacific yew tree, Taxus brevifolia and named it taxol. Later it was discovered that endophytic fungi in the bark synthesize paclitaxel.

Paclitaxel is currently being indicated to lung, breast and ovarian cancer as well as  head and neck cancer, and advanced forms of Kaposi’s sarcoma. 

The administration of paclitaxel (Taxol®) through intravenous infusions was achieved by using Cremophor® EL as a vehicle to entrap the drug in micelles and keep it in solution, which affects the disposition of paclitaxel and is responsible for the nonlinear pharmacokinetics of the drug, especially at higher dose levels. (http://www.futuremedicine.com/doi/pdf/10.2217/pgs.10.32)

Although Nonlinear pharmacokinetics (dose-dependented kinetics) may occur in all aspects of pharmacokinetics (absorption, distribution, and/or elimination), it focus on the in the metabolism or MichaelisMenten (MM) kinetics of the drug. http://archive.ajpe.org/legacy/pdfs/aj650212.pdf

Briefly, it is known that some of these adverse effects such as hypersensitivity reactions were diminished with the administration of corticosteroids and H1 and H2 antihistamine premedication, and by reducing the incidence of grade 3/4 neutropenia with the administration of granulocyte colony-stimulating factors (G-CSF) and shortening paclitaxel infusion time from 24 to 3 h. However, the neurotoxicity, which was believed to be caused by either paclitaxel or Cremophor EL, could not be controlled and became the dose-limiting toxicity of the drug. It was later on found that paclitaxel itself was responsible to the neurotoxicity effects (http://annonc.oxfordjournals.org/content/6/7/699.abstract)

Pharmacokinetics and Pharmacodynamics

The selection of pharmacokinetic (PK) parameter end points and basic model types for exposure-toxicity relationships of paclitaxel is usually based on tradition rather than physiological relevance.

pharmacokinetic (PK)-pharmacodynamic (PD) relationships for paclitaxel are still most commonly described with empirically-designed threshold models, which have little or no mechanistic basis and lack usefulness when applied to conditions (eg, schedules, vehicles, or routes of administration) different from those from which they were originally derived. (http://jco.ascopubs.org/content/21/14/2803.long). As such, the AUC of the unbound paclitaxel is highly important as a pharmacokinetic parameter to describe exposure-neutropenia relationships (the unbound ptx was not evaluated yet). (http://clincancerres.aacrjournals.org.rproxy.tau.ac.il/content/1/6/599.full.pdf+html)

The clearance of Cremophor EL in patients was found to be time-dependent, resulting in disproportional increases in systemic exposure being associated with shortening of infusion from 3 hours to 1 hour.

One study (http://clincancerres.aacrjournals.org/content/1/6/599), compare the pharmacokinetics and pharmacodynamics (PD) of paclitaxel between Phase I trials of 3- and 24-h infusions and to determine the most informative pharmacokinetic parameter to describe the PD. The study had 3 main goals

  • (a) to compare the PK and PD of paclitaxel between Phase I studies of 3- and 24-h infusion,
  • (b) to examine the relationship between PK and PD
  • (c) to determine the most informative pharmacokinetic parameter to describe the PD.

Note: Although this study was conducted in ~1993-1995, is has been cited extensively and paved the was to other clinical trials with similar results.

27 patients were treated in a Phase I study of paclitaxel by a 3-h infusion at one of six doses: 105, 135, 180, 210, 240, and 270 mg/m2. Pharmacokinetic data were obtained from all patients. Paclitaxel concentrations were measured in the plasma and urine using HPLC. Similar eligibility criteria were designed for the 24-hr infusion with these doses were 49.5, 75, 105, 135, and 180 mg/m2 . Plasma and urine samples for pharmacokinetic evaluation of paclitaxel were collected.

Pharmacokinetic Analysis: Pharmacokinetic parameters, Cmax, AUC, t112, and MRT were obtained by a noncompartmental moment method. Cmax was actually observed peak concentration. AUC and MRT were computed by trapezoidal integration with extrapolation to infinite time.

Pharmacodynamic Analysis: The pharmacokinetic/pharmacodynamic relationships were modeled with the sigmoid maximum effect

Results:

Pharmacokinetic analysis:

The drug plasma concentration increased throughout the 3-h infusion period and began to decrease immediately upon cessation of the infusion with t112 of 9.9-16.0 h and MRT of 6.47-10.24 h (Fig. 1). Both Cmax and AUC increased with increasing doses (r = 0.865, P <0.001 for Cmax r 0.870, P < 0.001 for AUC), although the pharmacokinetic behavior appeared to be nonlinear (Fig. 2). The mean Cmax and AUC at a dose of 270 mg/m2 were more than 3-fold greater than those at a dose of 135 mg/m2. CL and V, decreased with increasing doses (Table 1). The urinary excretion of paclitaxel over 75 h was less than 15% of the dose administered, which indicated that non-renal excretion is the primary route of drug elimination.

The urinary excretion of paclitaxel over 75 h was less than 15% of the dose administered, which indicated that non-renal excretion is the primary route of drug elimination.

Comparison of PD between 3-h and 24-h Infusion

Groups. AUC and duration of plasma concentration (h) above (7>) 0.05-0.1 LM correlated with the % D in granulocytes with p values less than 0.05. The best parameter predicting granulocytopenia was T> 0.09 pM with the minimum of the Akaike Information Criterion. In the 24-h schedule, dose, AUC, and T > 0.04-0.07 pM were demonstrated to correlate with the % D in granulocytes. The best parameter predicting granulocytopenia in the 24-h schedule was T > 0.05 p.M.

Nonhematological toxicities such as peripheral neuropathy, hypotension, and arthralgialmyalgia mainly observed in the 3-h infusion group had no relationship with Cm or AUC which are much higher in the 3-h infusion group, although peripheral neuropathy and musculoskeletal toxicity have been suggested to be associated with AUC on a 6- (12) or 24-h (29) schedule.

Pharmacogenomics:

In the past, the major adverse effects encountered with Taxol were severe hypersensitivity reactions, mainly attributed to Cremophor EL; hematologic toxicity, primarily appearing in the form of severe neutropenia; and neurotoxicity, mainly seen as cumulative sensory peripheral neuropathy. The mechanism for the neurotoxicity has been demonstrated to involve ganglioneuropathy and axonopathy caused by dysfunctional microtubules in dorsal root ganglia, axons and Schwann cells.

Variability in paclitaxel pharmacokinetics has  been associated with the adverse effects of the  drug. Thus, polymorphisms in genes encoding  paclitaxel-metabolizing enzymes, transporters and therapeutic targets have been suggested  to contribute to the interindividual variability in toxicity and response.

Further characterization of  genes involved in paclitaxel elimination and drug  response was performed, including the identification of their most relevant genetic variants. The organic anion transporting polypeptide (OATP)  1B3 was identified as a key protein for paclitaxel hepatic uptake and polymorphisms in the genes encoding for paclitaxel metabolizing enzymes and transporters (CYP2C8, CYP3A4) CYP3A5, P-glycoprotein and OATP1B3) (http://www.futuremedicine.com/doi/pdf/10.2217/pgs.10.32)

***It is important to note that  the allele frequencies for many of these polymorphisms are subject to important ethnicity  specific differences, with some alleles exclusively present in specific populations (e.g., the Caucasian CYP2C8*3).

For the CYP2C8 gene, two alleles common in Caucasians that result in amino acid changes CYP2C8*3 (R139K; K399R) and CYP2C8*4 (I264M), were described. The former has been shown to possess an altered activity, while the latter does not seem to have functional
consequences. In addition, two CYP2C8 haplotypes were recently shown to confer an increased and reduced metabolizing activity, respectively.

CYP3A5 was found to be highly polymorphic owing to CYP3A5*3, CYP3A5*6 and CYP3A5*7 , with the latter two being African-specific polymorphisms.

Pharmacogenetic studies comparing the most relevant polymorphisms in these genes and paclitaxel pharmacokinetics have rendered contradictory results, with some studies finding no associations while others reported an effect for ABCB1, CYP3A4 or CYP2C8 polymorphisms on specific pharmacokinetic parameters.

Again, with respect to paclitaxel neurotoxicity risk, some studies have rendered positive results for ABCB1 , CYP2C8  and CYP3A5  polymorphisms, while others found no significant associations.

Note: These differences might be caused by underpowered studies and by differences in the patients under study.

Changes affecting microtubule  structure and/or composition have been shown to affect paclitaxel efficacy, probably by reducing drug–target affinity. Mainly, resistance to tubulin-binding agents has been associated with an overexpression of b-tubulin isotype III,
which seems to be caused by a deregulation of the microRNA family 200.

However, the clinical utility of these findings remains to be established; furthermore, the identification of biomarkers that could be used to individualize paclitaxel treatment remains a challenge.

In summary,

  1. Pharmacokinetics: Paclitaxel seems to have a non-linear (=dose-dependent) PK parameters.
  2. Pharmcokinetics- Pharmacodynamics: Previous clinical trials did NOT take into account the unbound concentrations of Ptx and therefore in the PK analysis, therefore newly designed clinical trials should take that into consideration. This is very important since the neurotoxicity is attributed to ptx and not its vehicle Cremophor (as shown in the PD analysis)
  3. Difficult to compare between the 3hr and 24hr infusion schedule as most clinical trials did NOT used similar dose-regime making the comparison very hard.
  4. Pharmacogenetics: Different polymorphisms seems to attribute to the been suggested  to contribute to the interindividual variability in toxicity and response.
  5. Prospective pharmacogenetic-guided clinical trials will be required in order to accurately establish the utility of the identified markers/strategies for patients and healthcare systems.

 

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Nanotechnology Tackles Brain Cancer

Author: Tilda Barliya PhD

Primary malignant central nervous system (CNS) tumors only represent about 2% of all cancers.  But treatment is elusive. Tumors may be embedded in regions of the brain that are critical to orchestrating the body’s vital functions, while they shed cells to invade other parts of the brain, forming more tumors too small to detect using conventional imaging techniques. Brain cancer’s location and ability to spread quickly makes treatment with surgery or radiation like fighting an enemy hiding out among minefields and caves, and explains why the term “brain cancer” is all too often associated with the word “inoperable.” Nanotechnology may alter this situation. It offers a new promise for cancer diagnosis and treatment. This emerging technology, by developing and manufacturing materials using atomic and molecular elements, can provide a platform for the combination of diagnostics, therapeutics and delivery to the tumor, with subsequent monitoring of the response. This review focuses on recent developments in cancer nanotechnology with particular attention to nanoparticle systems, important tools for the improvement of drug delivery in brain tumor.

Making treatment even more challenging, there is a system of blood vessels and protective cells in the brain — the blood brain barrier — that admits only essential nutrients and oxygen, and keeps out everything else, including about 95 percent of all drugs. This natural barrier puts serious limits on how much a patient can benefit from traditional chemotherapy and new cancer drugs.

The blood-brain barrier permits the exchange of essential nutrients and gases between the bloodstream and the brain, while blocking larger entities such as microbes, immune cells and most drugs from entering. This barrier system is a perfectly logical arrangement, since the brain is the most sensitive and complex organ in the human body and it would not make sense for it to become the battleground of infection and immune response.

This biological “demilitarization zone” is enforced by an elaborate and dense network of capillary vessels that feeds the brain and removes waste products. Each capillary vessel is bound by a single layer of endothelial cells, connected by “tight junctions,” thereby making it very difficult for most molecules to exit the capillaries and permeate into the brain.  Instead of “leaking” material, brain capillary walls closely regulate the flow of material using molecular pumps and receptors that recognize and transport nutrients such as glucose, nucleosides, and specific proteins into the brain. In other words, substances need to be pre-recognized to enter.

Since most drugs. including old-school chemotherapy, can not cross the BBB it very hard to treat brain-tumor patients.  In certain conditions such as grade IV glioblastoma, the BBB is loosened up (becomes more permeable  due to changes in the gene expression and tight-junction protein expression, making the cross over of materials much easier. Having  said that,  the loosened up BBB represent a double-edge sword as it not only allows the transfer of drugs but allow the escape of metastatic tumor cells.

Therefore, in order to enable drugs to enter the brain regardless of the presence of the BBB, nanotechnology has designed drugs that used the already-existing transporters located at the barrier. Among them are: glucose transporter,  transferrin transporter and LDL receptor.

Trojan Horse approach:

 Nanoparticles have excellent potential as carriers of drugs, because if they are small enough, they can penetrate the BBB. That way, a treatment could be injected into the bloodstream rather than performing surgery to insert it. Many researchers are exploring using nanoparticles in the manner of a Trojan horse, to carry treatments including chemotherapy, gene therapy, or immune boosters into the brain. As impressive as it may sound, receptor uptake of nanocarriers (Trojan horses) have also limitations;  this can limit the amount of therapy one person can have—if all of the receptors are taken up (filled) no more of the drug could get in.

 

Some of these extensive beautiful work conducted by several research labs including Dr. Raoul Kopleman, Dr. Miqin Zhang and Dr. Panos Fatouros  are summaried in this article “Nanotechnology Tackles Brain Tumors” (http://www.fightplga.org/files/monthly_feature_2005_dec.pdf).

I’d like to shift the discussion to FDA/EU-approved nanomedicine to treat brain tumors.

Using nanomedicines to treat brain tumors was first proposed more than three decades ago . Currently there is one nanoparticle treatment available to people with hard brain tumors: Nano-Therm therapy. Available at a clinic in Berlin, the treatment has been through trials in humans to demonstrate its safety and effectiveness. (http://www.dana.org/news/brainwork/detail.aspx?id=35524)

In the study, 59 patients with recurring glioblastoma treated with Nano-Therm therapy survived a median time of more than 13 months—more than double the control group, published in Neuro-Oncology in 2010.  The EU approved the treatment developed by Magforce, in July 2010.

Nano-Therm uses “thermotherapy,” which involves surgery to insert a liquid containing 15 nanometer-wide magnetic particles into the brain tumor. Next, the patient being treated lies in a machine that emits an alternating magnetic field. This causes the nanoparticles, which have an iron oxide core, to oscillate, penetrating the tumor cells. The longer the magnetic field is on, the warmer the nanoparticles grow. Doctors can take the heat up to about 45 degrees Celsius, where the tumor cells are primed for chemotherapy or radiotherapy, or even higher, which can destroy the tumor cells. It important thought to ensure that normal brain cells are not affected.

The main aim is to build a multifunctional nano-carrier; one that contains 3  aspects :

  • A target moiety- that will guide the nanoparticle (NP) to the brain tumors. Preferably will use a specific receptor to penetrate through the BBB.
  • An imaging agent- that will enable visualization of the target ” i.e brain rumor” .  MRI contrast agent are good such as gadolinium, fluorescent probes and quantum dots  are good candidates.
  • A destructive drug/toxin- that will eliminate the tumor cells.

In summary:

Nanotechnology has huge potential and a long way to go, thought there is a growing consensus that brain cancer is a problem in need of a radically different solution, and that nanotechnology fits the bill. Functionalized nanoparticles could provide precision detection, targeted treatment, and real-time tracking that conventional technology lacks. For a disease in which only 5 percent to 32 percent of patients are likely to survive after five years, large hope is riding on the potential success of “small” technology.

 

Ref:

Click to access monthly_feature_2005_dec.pdf

http://www.nanowerk.com/spotlight/spotid=6269.php#axzz2D4yx1btl

Click to access amiji.pdf

http://www.dana.org/news/brainwork/detail.aspx?id=35524

 

 

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FDA Guidelines For Developmental and Reproductive Toxicology (DART) Studies for Small Molecules. Author-Writer: Stephen J. Williams, Ph.D.

This posting is a follow-up on the Report on the Fall Mid-Atlantic Society of Toxicology Meeting “Reproductive Toxicology of Biologics: Challenges and Considerations post and gives a brief synopsis of the current state of FDA regulatory guidelines with respect to DART studies on small molecule (non-biological based) therapeutics.    The following is adapted from the book Principles and Methods of Toxicology by Dr. A Wallace Hayes (1) and is an excellent reference on reproductive toxicology and testing methods.

Chemical insult occurs to the human reproductive system at a multitude of stages in development and the life cycle, leading to the extensive testing which must be performed to diligently the reproductive and development toxicity of a chemical/drug.  Abnormalities and toxic manifestations in the offspring may result from insult to the adult reproductive (either female or male) and neuroendocrine systems, as well as damage to the embryo resulting in embryolethality, fetus at any period during organogenesis, juvenile development or, in the case of certain antibody therapies, immune system development.  The latter, toxic insult to the developing immune system could possibly be manifested as either an immune defect in the newborn or, later in life, as tolerance to said therapy.  It is estimated that exposure to the pregnant woman, of either environmental contaminants or drug, is significant.  It is estimated that a mother may be taking an average of 8-9 different drug preparations, mostly over the counter preparations such as antacids, vitamin preparations, cathartics etc. with the maximal drug intake occurring between 24 and 36 weeks of gestation.

Toxic insult to the developing embryo is dependent on

  • Fetal development stage during drug/chemical exposure
  • Maternal/placental xenobiotic metabolism
  • Pharmacokinetic parameters affecting bioavailability and fetal/maternal drug binding

The following table shows the dependency of developmental stage to teratogenicity: adapted from J. Manson, H. Zenick, and R.D. Costlow from Principles and Methods of Toxicology.

Developmental Stage Major Susceptibility
Preimplantation Embryolethality
Organogenesis Births defects; embryolethality
Fetal Growth retardation, fetal death, functional deficits
Neonatal Growth retardation, nervous system alterations, immune and endocrine systems

It is not generally accepted that there is a dose dependency of teratogenesis however most teratogens have specific mechanisms of action and teratogenic effects occur at much lower doses than result in maternal toxicity.   However, the developmental toxicity may be manifested later in life, including as reproductive toxicity affecting adult fertility and familial generations.

FDA Guidelines for DART Studies on Non-Biologics (Small Molecule Therapeutics)

The basic design for DART studies incorporate the aforementioned principles of tetralogy:

  • developmental stage of fetal exposure
  • parental effects on reproduction and development
  • toxicity may be manifested over multiple generations including fertility rates

Therefore two designs are generally used for DART studies

  1. exposure across several generations
  2. exposure during one generation

FDA requires one control group and two treatment groups, and evaluation of at least two species.  However, most studies will use two rodent and one nonrodent species.

Multigenerational Design

Multigenerational DART studies are conducted for compounds likely to concentrate in the body following long-term exposure.  Examples of types of compounds include pesticides and food additives.

Figure 1.  General Design of a Multigenerational DART study.  Weanlings (30-30 days of age) from the parental generation are treated for a period up to 60 days. At 100-120 days of parental generation, animals are mated.  Fx = filialx .

Three Segment, Single Generation Tests

The single generation design is more suitable for DART studies on drugs, as most therapeutic would be taken over short periods (during pregnancy) and have relatively short half-lives in the body.  FDA guidelines separate these studies in three phases:

I.            Phase I: evaluation of fertility and general reproductive performance

II.            Phase II: assessment of teratogenicity and embryotoxicity

III.            Phase III: peri- and postnatal evaluations.

All figures are adapted from Principles and Methods of Toxicology.(1)

FDA guidelines Guidance for Industry Reproductive and Developmental Toxicities —Integrating Study Results to Assess Concerns can be found at: http://www.fda.gov/downloads/Drugs/GuidanceComplianceRegulatoryInformation/Guidances/ucm079240.pdf

FDA Guideline for reproductive toxicity testing for small molecule therapeutics can be found at:

http://www.fda.gov/downloads/Drugs/GuidanceComplianceRegulatoryInformation/Guidances/ucm074950.pdf

1.            Hayes, A. W. (1986) Principles and Methods of Toxicology, Raven Press, New York

Other research papers on Pharmaceutical Intelligence and Reproductive Biology, Bio Insrumentation, Endocrinology Genetics were published on this Scientific Web site as follows

Non-small Cell Lung Cancer drugs – where does the Future lie?

Reboot evidence-based medicine and reconsider the randomized, placebo-controlled clinical trial

Every sperm is sacred: Sequencing DNA from individual cells vs “humans as a whole.”

Leptin and Puberty

Gene Trap Mutagenesis in Reproductive Research

Genes involved in Male Fertility and Sperm-egg Binding

Hope for Male Contraception: A small molecule that inhibits a protein important for chromatin organization can cause reversible sterility in male mice

Pregnancy with a Leptin-Receptor Mutation

The contribution of comparative genomic hybridization in reproductive medicine

Sperm collide and crawl the walls in chaotic journey to the ovum

Impact of evolutionary selection on functional regions: The imprint of evolutionary selection on ENCODE regulatory elements is manifested between species and within human populations

Biosimilars: CMC Issues and Regulatory Requirements

Biosimilars: Intellectual Property Creation and Protection by Pioneer and by Biosimilar Manufacturers

Assisted Reproductive Technology Cycles and Cumulative Birth Rates

Innovations in Bio instrumentation in Reproductive Clinical and Male Fertility Labs in the US

Increased risks of obesity and cancer, Decreased risk of type 2 diabetes: The role of Tumor-suppressor phosphatase and tensin homologue (PTEN)

Guidelines for the welfare and use of animals in cancer research

Every sperm is sacred: Sequencing DNA from individual cells vs “humans as a whole.”

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