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Archive for the ‘Cell Biology’ Category


Identification of Novel genes in human that fight COVID-19 infection

Reporter: Amandeep Kaur, B.Sc., M.Sc. (ept. 5/2021)

Scientists have recognized human genes that fight against the SARS-CoV-2 viral infection. The information about genes and their function can help to control infection and aids the understanding of crucial factors that causes severe infection. These novel genes are related to interferons, the frontline fighter in our body’s defense system and provide options for therapeutic strategies.

The research was published in the journal Molecular Cell.

Sumit K. Chanda, Ph.D., professor and director of the Immunity and Pathogenesis Program at Sanford Burnham Prebys reported in the article that they focused on better understanding of the cellular response and downstream mechanism in cells to SARS-CoV-2, including the factors which causes strong or weak response to viral infection. He is the lead author of the study and explained that in this study they have gained new insights into how the human cells are exploited by invading virus and are still working towards finding any weak point of virus to develop new antivirals against SARS-CoV-2.

With the surge of pandemic, researchers and scientists found that in severe cases of COVID-19, the response of interferons to SARS-CoV-2 viral infection is low. This information led Chanda and other collaborators to search for interferon-stimulated genes (ISGs), are genes in human which are triggered by interferons and play important role in confining COVID-19 infection by controlling their viral replication in host.

The investigators have developed laboratory experiments to identify ISGs based on the previous knowledge gathered by the outbreak of SARS-CoV-1 from 2002-2004 which was similar to COVID-19 pandemic caused by SARS-CoV-2 virus.

The article reports that Chanda mentioned “we found that 65 ISGs controlled SAR-CoV-2 infection, including some that inhibited the virus’ ability to enter cells, some that suppressed manufacture of the RNA that is the virus’s lifeblood, and a cluster of genes that inhibited assembly of the virus.” They also found an interesting fact about ISGs that some of these genes revealed control over unrelated viruses, such as HIV, West Nile and seasonal flu.

Laura Martin-Sancho, Ph.D., a senior postdoctoral associate in the Chanda lab and first author of the study reported in the article that they identified 8 different ISGs that blocked the replication of both SARS-CoV-1 and CoV-2 in the subcellular compartments responsible for packaging of proteins, which provide option to exploit these vulnerable sites to restrict infection. They are further investigating whether the genetic variability within the ISGs is associated with COVID-19 severity.

The next step for researchers will be investigating and observing the biology of variants of SARS-CoV-2 that are evolving and affecting vaccine efficacy. Martin-Sancho mentioned that their lab has already started gathering all the possible variants for further investigation.

“It’s vitally important that we don’t take our foot off the pedal of basic research efforts now that vaccines are helping control the pandemic,” reported in the article by Chanda.

“We’ve come so far so fast because of investment in fundamental research at Sanford Burnham Prebys and elsewhere, and our continued efforts will be especially important when, not if, another viral outbreak occurs,” concluded Chanda.

Source: https://medicalxpress.com/news/2021-04-covid-scientists-human-genes-infection.html

Reference: Laura Martin-Sancho et al. Functional Landscape of SARS-CoV-2 Cellular Restriction, Molecular Cell (2021). DOI: 10.1016/j.molcel.2021.04.008

Other related articles were published in this Open Access Online Scientific Journal, including the following:

Fighting Chaos with Care, community trust, engagement must be cornerstones of pandemic response

Reporter: Amandeep Kaur

https://pharmaceuticalintelligence.com/2021/04/13/fighting-chaos-with-care/

Mechanism of Thrombosis with AstraZeneca and J & J Vaccines: Expert Opinion by Kate Chander Chiang & Ajay Gupta, MD

Reporter & Curator: Dr. Ajay Gupta, MD

https://pharmaceuticalintelligence.com/2021/04/14/mechanism-of-thrombosis-with-astrazeneca-and-j-j-vaccines-expert-opinion-by-kate-chander-chiang-ajay-gupta-md/

T cells recognize recent SARS-CoV-2 variants

Reporter: Aviva Lev-Ari, PhD, RN

https://pharmaceuticalintelligence.com/2021/03/30/t-cells-recognize-recent-sars-cov-2-variants/

Need for Global Response to SARS-CoV-2 Viral Variants

Reporter: Aviva Lev-Ari, PhD, RN

https://pharmaceuticalintelligence.com/2021/02/12/need-for-global-response-to-sars-cov-2-viral-variants/

Mechanistic link between SARS-CoV-2 infection and increased risk of stroke using 3D printed models and human endothelial cells

Reporter: Adina Hazan, PhD

https://pharmaceuticalintelligence.com/2020/12/28/mechanistic-link-between-sars-cov-2-infection-and-increased-risk-of-stroke-using-3d-printed-models-and-human-endothelial-cells/

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Embryogenesis in Mechanical Womb

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

A highly effective platforms for the ex utero culture of post-implantation mouse embryos have been developed in the present study by scientists of the Weizmann Institute of Science in Israel. The study was published in the journal Nature. They have grown more than 1,000 embryos in this way. This study enables the appropriate development of embryos from before gastrulation (embryonic day (E) 5.5) until the hindlimb formation stage (E11). Late gastrulating embryos (E7.5) are grown in three-dimensional rotating bottles, whereas extended culture from pre-gastrulation stages (E5.5 or E6.5) requires a combination of static and rotating bottle culture platforms.

At Day 11 of development more than halfway through a mouse pregnancy the researchers compared them to those developing in the uteruses of living mice and were found to be identical. Histological, molecular and single-cell RNA sequencing analyses confirm that the ex utero cultured embryos recapitulate in utero development precisely. The mouse embryos looked perfectly normal. All their organs developed as expected, along with their limbs and circulatory and nervous systems. Their tiny hearts were beating at a normal 170 beats per minute. But, the lab-grown embryos becomes too large to survive without a blood supply. They had a placenta and a yolk sack, but the nutrient solution that fed them through diffusion was no longer sufficient. So, a suitable mechanism for blood supply is required to be developed.

Till date the only way to study the development of tissues and organs is to turn to species like worms, frogs and flies that do not need a uterus, or to remove embryos from the uteruses of experimental animals at varying times, providing glimpses of development more like in snapshots than in live videos. This research will help scientists understand how mammals develop and how gene mutations, nutrients and environmental conditions may affect the fetus. This will allow researchers to mechanistically interrogate post-implantation morphogenesis and artificial embryogenesis in mammals. In the future it may be possible to develop a human embryo from fertilization to birth entirely outside the uterus. But the work may one day raise profound questions about whether other animals, even humans, should or could be cultured outside a living womb.

References:

https://www.nature.com/articles/s41586-021-03416-3

https://www.sciencedirect.com/science/article/pii/S0092867414000750?via%3Dihub

https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1469-185X.1978.tb00993.x

https://www.nature.com/articles/199297a0

https://rep.bioscientifica.com/view/journals/rep/35/1/jrf_35_1_018.xml

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First single-course ‘curative’ CRISPR Shot by Intellia rivals Alnylam, Ionis and Pfizer

Reporter: Aviva Lev-Ari, PhD, RN

 

Intellia to kick-start first single-course ‘curative’ CRISPR shot, as it hopes to beat rivals Alnylam, Ionis and Pfizer

It’s been a good year for Intellia: One of its founders, Jennifer Doudna, Ph.D., nabbed the Nobel Prize in Chemistry for her CRISPR research.

Now, the biotech she helped build is putting that to work, saying it now plans the world’s first clinical trial for a single-course therapy that “potentially halts and reverses” a condition known as hereditary transthyretin amyloidosis with polyneuropathy (hATTR-PN).

This genetic disorder occurs when a person is born with a specific DNA mutation in the TTR gene, which causes the liver to produce a protein called transthyretin (TTR) in a misfolded form and build up in the body.

hATTR can manifest as polyneuropathy (hATTR-PN), which can lead to nerve damage, or cardiomyopathy (hATTR-CM), which involves heart muscle disease that can lead to heart failure.

This disorder has seen a lot of interest in recent years, with an RNAi approach from Alnylam seeing an approval for Onpattro a few years back, specifically for hATTR in adults with damage to peripheral nerves.

Ionis Pharmaceuticals and its rival RNAi drug Tegsedi also saw an approval in 2018 for a similar indication.

They both battle with Pfizer’s older med tafamidis, which has been approved in Europe for years in polyneuropathy, and the fight could spread to the U.S. soon.

The drug, now marketed as Vyndaqel and Vyndamax, snatched up an FDA nod last May to treat both hereditary and wild-type ATTR patients with a heart condition called cardiomyopathy.

While coming into an increasingly crowed R&D area, Intellia is looking for a next-gen approach, and has been given the go-ahead by regulators ion the U.K, to start a phase 1 this year.

The idea is for Intellia’s candidate NTLA-2001, which is also partnered with Regeneron, to go beyond its rivals and be the first curative treatment for ATTR.

By applying the company’s in vivo liver knockout technology, NTLA-2001 allows for the possibility of lifelong transthyretin (TTR) protein reduction after a single course of treatment. If this works, this could in essence cure patients of the their disease.

The 38-patient is set to start by year’s end.

“Starting our global NTLA-2001 Phase 1 trial for ATTR patients is a major milestone in Intellia’s mission to develop medicines to cure severe and life-threatening diseases,” said Intellia’s president and chief John Leonard, M.D.

“Our trial is the first step toward demonstrating that our therapeutic approach could have a permanent effect, potentially halting and reversing all forms of ATTR. Once we have established safety and the optimal dose, our goal is to expand this study and rapidly move to pivotal studies, in which we aim to enroll both polyneuropathy and cardiomyopathy patients.”

SOURCE

https://www.fiercebiotech.com/biotech/intellia-to-kickstart-first-single-course-curative-crispr-shot-as-it-hopes-to-beat-rivals

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

 

Familial transthyretin amyloid polyneuropathy

Curator: Larry H. Bernstein, MD, FCAP

https://pharmaceuticalintelligence.com/2016/06/10/familial-transthyretin-amyloid-polyneuropathy/

 

Stabilizers that prevent transthyretin-mediated cardiomyocyte amyloidotic toxicity

Reporter and curator: Larry H. Bernstein, MD, FCAP

https://pharmaceuticalintelligence.com/2013/12/02/stabilizers-that-prevent-transthyretin-mediated-cardiomyocyte-amyloidotic-toxicity/

 

Transthyretin amyloid cardiomyopathy (ATTR-CM): U.S. FDA APPROVES VYNDAQEL® AND VYNDAMAX™ for this Rare and Fatal Disease

Reporter: Aviva Lev-Ari, PhD, RN

https://pharmaceuticalintelligence.com/2019/10/29/transthyretin-amyloid-cardiomyopathy-attr-cm-u-s-fda-approves-vyndaqel-and-vyndamax-for-this-rare-and-fatal-disease/

 

Alnylam Announces First-Ever FDA Approval of an RNAi Therapeutic, ONPATTRO™ (patisiran) for the Treatment of the Polyneuropathy of Hereditary Transthyretin-Mediated Amyloidosis in Adults

Reporter: Aviva Lev-Ari, PhD, RN

https://pharmaceuticalintelligence.com/2018/08/13/alnylam-announces-first-ever-fda-approval-of-an-rnai-therapeutic-onpattro-patisiran-for-the-treatment-of-the-polyneuropathy-of-hereditary-transthyretin-mediated-amyloidosis-in-adults/

 

 

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Reporter: Adina Hazan, PhD

Elizabeth Unger from the Tian group at UC Davis, Jacob Keller from the Looger lab from HHMI, Michael Altermatt from the Gradinaru group at California Institute of Technology, and colleagues did just this, by redesigned the binding pocket of periplasmic binding proteins (PBPs) using artificial intelligence, such that it became a fluorescent sensor specific for serotonin. Not only this, the group showed that it could express and use this molecule to detect serotonin on the cell, tissue, and whole animal level.

By starting with a microbial PBP and early version of an acetyl choline sensor (iAChSnFR), the scientists used machine learning and modeling to redesign the binding site to exhibit a higher affinity and specificity to serotonin. After three repeats of mutagenesis, modeling, and library readouts, they produced iSeroSnFR. This version harbors 19 mutations compared to iAChSnFR0.6 and a Kd of 310 µM. This results in an increase in fluorescence in HEK293T cells expressing the serotonin receptor of 800%. Of over 40 neurotransmitters, amino acids, and small molecules screened, only two endogenous molecules evoked some fluorescence, but at significantly higher concentrations.

To acutely test the ability of the sensor to detect rapid changes of serotonin in the environment, the researchers used caged serotonin, a technique in which the serotonin is rapidly released into the environment with light pulses, and showed that iSeroSnFR accurately and robustly produced a signal with each flash of light. With this tool, it was then possible to move to ex-vivo mouse brain slices and detect endogenous serotonin release patterns across the brain. Three weeks after targeted injection of iSeroSnFR to specifically deliver the receptor into the prefrontal cortex and dorsal striatum, strong fluorescent signal could be detected during perfusion of serotonin or electrical stimulation.

Most significantly, this molecule was also shown to be detected in freely moving mice, a tool which could offer critical insight into the acute role of serotonin regulation during important functions such as mood and alertness. Through optical fiber placements in the basolateral amygdala and prefrontal cortex, the team measured dynamic and real-time changes in serotonin release in fear-trained mice, social interactions, and sleep wake cycles. For example, while both areas of the brain have been established as relevant to the fear response, they reliably tracked that the PFC response was immediate, while the BSA displayed a delayed response. This additional temporal resolution of neuromodulation may have important implications in neurotransmitter pharmacology of the central nervous system.

This study provided the scientific community with several insights and tools. The serotonin sensor itself will be a critical tool in the study of the central nervous system and possibly beyond. Additionally, an AI approach to mutagenesis in order to redesign a binding pocket of a receptor opens new avenues to the development of pharmacological tools and may lead to many new designs in therapeutics and research.

SOURCE:

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The Nobel Prize in Chemistry 2020: Emmanuelle Charpentier & Jennifer A. Doudna

Reporters: Stephen J. Williams, Ph.D. and Aviva Lev-Ari, PhD, RN

 

UPDATED on 11/12/2020

Harvard’s Jack Szostak congratulates former advisee Jennifer Doudna

It was a toast from one Nobel laureate to another, sweetened by the pride of a mentor to a prized student.

When Jennifer Doudna Ph.D. ’89 was honored on Wednesday with the Nobel Prize in chemistry for her work on the CRISPR gene-editing technique, she became the second person to gain such an honor from the lab of Jack Szostak, a genetics professor at Harvard Medical School and Massachusetts General Hospital, and professor of chemistry and chemical biology at Harvard’s Faculty of Arts and Sciences.

Szostak, who won the Nobel Prize in physiology or medicine in 2009 for work on how telomere caps keep the body’s chromosomes from breaking down, advised Doudna’s doctoral work on RNA and on Wednesday raised a glass in honor of Doudna, now at the University of California, Berkeley. In a tweet, Szostak expressed his delight at seeing someone he once guided through her early scientific steps soar to science’s highest reaches:

Doudna received the prize together with Emmanuelle Charpentier, for their work discovering and developing CRISPR as a precise gene-editing tool. In just the eight years since the pair announced their discovery the use of the technique has rapidly spread to a host of fields, allowing researchers to alter the code of life and develop resistant crops, new medical therapies, and even anticipate curing inherited diseases.

 

UPDADTED on 11/2/2020

 

Announcement of the Nobel Prize in Chemistry 2020

Live webcast from the press conference where the Royal Swedish Academy of Sciences will announce the Nobel Prize in Chemistry 2020.

 

 

The Royal Swedish Academy of Sciences has decided to award the Nobel Prize in Chemistry 2020 to

Emmanuelle Charpentier
Max Planck Unit for the Science of Pathogens, Berlin, Germany

Jennifer A. Doudna
University of California, Berkeley, USA

“for the development of a method for genome editing”

Genetic scissors: a tool for rewriting the code of life

Emmanuelle Charpentier and Jennifer A. Doudna have discovered one of gene technology’s sharpest tools: the CRISPR/Cas9 genetic scissors. Using these, researchers can change the DNA of animals, plants and microorganisms with extremely high precision. This technology has had a revolutionary impact on the life sciences, is contributing to new cancer therapies and may make the dream of curing inherited diseases come true.

Researchers need to modify genes in cells if they are to find out about life’s inner workings. This used to be time-consuming, difficult and sometimes impossible work. Using the CRISPR/Cas9 genetic scissors, it is now possible to change the code of life over the course of a few weeks.

“There is enormous power in this genetic tool, which affects us all. It has not only revolutionised basic science, but also resulted in innovative crops and will lead to ground-breaking new medical treatments,” says Claes Gustafsson, chair of the Nobel Committee for Chemistry.

As so often in science, the discovery of these genetic scissors was unexpected. During Emmanuelle Charpentier’s studies of Streptococcus pyogenes, one of the bacteria that cause the most harm to humanity, she discovered a previously unknown molecule, tracrRNA. Her work showed that tracrRNA is part of bacteria’s ancient immune system, CRISPR/Cas, that disarms viruses by cleaving their DNA.

Charpentier published her discovery in 2011. The same year, she initiated a collaboration with Jennifer Doudna, an experienced biochemist with vast knowledge of RNA. Together, they succeeded in recreating the bacteria’s genetic scissors in a test tube and simplifying the scissors’ molecular components so they were easier to use.

In an epoch-making experiment, they then reprogrammed the genetic scissors. In their natural form, the scissors recognise DNA from viruses, but Charpentier and Doudna proved that they could be controlled so that they can cut any DNA molecule at a predetermined site. Where the DNA is cut it is then easy to rewrite the code of life.

Since Charpentier and Doudna discovered the CRISPR/Cas9 genetic scissors in 2012 their use has exploded. This tool has contributed to many important discoveries in basic research, and plant researchers have been able to develop crops that withstand mould, pests and drought. In medicine, clinical trials of new cancer therapies are underway, and the dream of being able to cure inherited diseases is about to come true. These genetic scissors have taken the life sciences into a new epoch and, in many ways, are bringing the greatest benefit to humankind.

Illustrations

The illustrations are free to use for non-commercial purposes. Attribute ”© Johan Jarnestad/The Royal Swedish Academy of Sciences”

Illustration: Using the genetic scissors (pdf)
Illustration: Streptococcus’ natural immune system against viruses:CRISPR/Cas9 pdf)
Illustration: CRISPR/Cas9 genetic scissors (pdf)

Read more about this year’s prize

Popular information: Genetic scissors: a tool for rewriting the code of life (pdf)
Scientific Background: A tool for genome editing (pdf)

Emmanuelle Charpentier, born 1968 in Juvisy-sur-Orge, France. Ph.D. 1995 from Institut Pasteur, Paris, France. Director of the Max Planck Unit for the Science of Pathogens, Berlin, Germany.

Jennifer A. Doudna, born 1964 in Washington, D.C, USA. Ph.D. 1989 from Harvard Medical School, Boston, USA. Professor at the University of California, Berkeley, USA and Investigator, Howard Hughes Medical Institute.

SOURCE

https://www.nobelprize.org/prizes/chemistry/2020/press-release/

 

Nobel Prize in Chemistry awarded to scientists who discovered CRISPR gene editing tool for ‘rewriting the code of life’

(CNN)The Nobel Prize in Chemistry has been awarded to Emmanuelle Charpentier and Jennifer A. Doudna for the development of a method for genome editing.

They discovered one of gene technology’s sharpest tools: the CRISPR/Cas9 genetic scissors. Using these, researchers can change the DNA of animals, plants and micro-organisms with extremely high precision.
Before announcing the winners on Wednesday, Göran K. Hansson, secretary-general for the Royal Swedish Academy of Sciences, said that this year’s prize was about “rewriting the code of life.”
The American biochemist Jennifer A. Doudna (left) and French microbiologist Emmanuelle Charpentier, pictured together in 2016.
 
The CRISPR/Cas9 gene editing tools have revolutionized the molecular life sciences, brought new opportunities for plant breeding, are contributing to innovative cancer therapies and may make the dream of curing inherited diseases come true, according to a press release from the Nobel committee.
 
 
There have also been some ethical concerns around the CRISPR technology, however.
Charpentier, a French microbiologist, and Doudna, an American biochemist, are the first women to jointly win the Nobel Prize in Chemistry, and the sixth and seventh women to win the chemistry prize.
close dialog

 

Jennifer Doudna wins 2020 Nobel Prize in chemistry

 

First Day in a Nobel Life: Jennifer Doudna

12,365 views
Oct 7, 2020
 
Scenes from day that UC Berkeley Professor Jennifer Doudna won the Nobel Prize For the full story, visit: https://news.berkeley.edu/2020/10/07/… University of California, Berkeley, biochemist Jennifer Doudna today won the 2020 Nobel Prize in Chemistry, sharing it with colleague Emmanuelle Charpentier for the co-development of CRISPR-Cas9, a genome editing breakthrough that has revolutionized biomedicine. CRISPR-Cas9 allows scientists to rewrite DNA — the code of life — in any organism, including human cells, with unprecedented efficiency and precision. The groundbreaking power and versatility of CRISPR-Cas9 has opened up new and wide-ranging possibilities across biology, agriculture and medicine, including the treatment of thousands of intractable diseases. Doudna and Charpentier, director of the Max Planck Institute for Infection Biology, will share the 10 million Swedish krona (more than $1 million) prize. “This great honor recognizes the history of CRISPR and the collaborative story of harnessing it into a profoundly powerful engineering technology that gives new hope and possibility to our society,” said Doudna. “What started as a curiosity‐driven, fundamental discovery project has now become the breakthrough strategy used by countless researchers working to help improve the human condition. I encourage continued support of fundamental science as well as public discourse about the ethical uses and responsible regulation of CRISPR technology.” Video by Clare Major & Roxanne Makasdjian
SOURCE

 

Jennifer Doudna wins 2020 Nobel Prize in chemistry

 

Jennifer Doudna in the PBS Movie CRISPR

Our critically-acclaimed documentary HUMAN NATURE is now streaming on NETFLIX. #HumanNatureFilm. Find out more about the film on our website.

 

Other Articles on the Nobel Prize in this Open Access Journal Include:

2020 Nobel Prize for Physiology and Medicine for Hepatitis C Discovery goes to British scientist Michael Houghton and US researchers Harvey Alter and Charles Rice

CONTAGIOUS – About Viruses, Pandemics and Nobel Prizes at the Nobel Prize Museum, Stockholm, Sweden 

AACR Congratulates Dr. William G. Kaelin Jr., Sir Peter J. Ratcliffe, and Dr. Gregg L. Semenza on 2019 Nobel Prize in Physiology or Medicine

2018 Nobel Prize in Physiology or Medicine for contributions to Cancer Immunotherapy to James P. Allison, Ph.D., of the University of Texas, M.D. Anderson Cancer Center, Houston, Texas. Dr. Allison shares the prize with Tasuku Honjo, M.D., Ph.D., of Kyoto University Institute, Japan

2017 Nobel prize in chemistry given to Jacques Dubochet, Joachim Frank, and Richard Henderson  for developing cryo-electron microscopy

2016 Nobel Prize in Chemistry awarded for development of molecular machines, the world’s smallest mechanical devices, the winners: Jean-Pierre Sauvage, J. Fraser Stoddart and Bernard L. Feringa

Correspondence on Leadership in Genomics and other Gene Curations: Dr. Williams with Dr. Lev-Ari

Programming life: An interview with Jennifer Doudna by Michael Chui, a partner of the McKinsey Global Institute

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Double Mutant PI3KA Found to Lead to Higher Oncogenic Signaling in Cancer Cells

Curator: Stephen J. Williams, PhD

PIK3CA (Phosphatidylinsitol 4,5-bisphosphate (PIP2) 3-kinase catalytic subunit α) is one of the most frequently mutated oncogenes in various tumor types ([1] and http://www.sanger.ac.uk/genetics/CGP/cosmic). Oncogenic mutations leading to the overactivation of PIK3CA, especially in context in of inactivating PTEN mutations, result in overtly high signaling activity and associated with the malignant phenotype.

In a Perspective article (Double trouble for cancer gene: Double mutations in an oncogene enhance tumor growth) in the journal Science[2], Dr. Alex Toker discusses the recent results of Vasan et al. in the same issue of Science[3] on the finding that double mutations in the same allele of PIK3CA are more frequent in cancer genomes than previously identified and these double mutations lead to increased PI3K pathway activation, increased tumor growth, and increased sensitivity to PI3K inhibitors in human breast cancer.

 

 

From Dr. Melvin Crasto blog NewDrugApprovals.org

Alpelisib: PIK3CA inhibitor:

Alpelisib: New PIK3CA inhibitor approved for HER2 negative metastatic breast cancer

 

FDA approves first PI3K inhibitor for breast cancer

syn https://newdrugapprovals.org/2018/06/25/alpelisib-byl-719/

Today, the U.S. Food and Drug Administration approved Piqray (alpelisib) tablets, to be used in combination with the FDA-approved endocrine therapy fulvestrant, to treat postmenopausal women, and men, with hormone receptor (HR)-positive, human epidermal growth factor receptor 2 (HER2)-negative, PIK3CA-mutated, advanced or metastatic breast cancer (as detected by an FDA-approved test) following progression on or after an endocrine-based regimen.

The FDA also approved the companion diagnostic test, therascreen PIK3CA RGQ PCR Kit, to detect the PIK3CA mutation in a tissue and/or a liquid biopsy. Patients who are negative by

May 24, 2019

Today, the U.S. Food and Drug Administration approved Piqray (alpelisib) tablets, to be used in combination with the FDA-approved endocrine therapy fulvestrant, to treat postmenopausal women, and men, with hormone receptor (HR)-positive, human epidermal growth factor receptor 2 (HER2)-negative, PIK3CA-mutated, advanced or metastatic breast cancer (as detected by an FDA-approved test) following progression on or after an endocrine-based regimen.

The FDA also approved the companion diagnostic test, therascreen PIK3CA RGQ PCR Kit, to detect the PIK3CA mutation in a tissue and/or a liquid biopsy. Patients who are negative by the therascreen test using the liquid biopsy should undergo tumor biopsy for PIK3CA mutation testing.

“Piqray is the first PI3K inhibitor to demonstrate a clinically meaningful benefit in treating patients with this type of breast cancer. The ability to target treatment to a patient’s specific genetic mutation or biomarker is becoming increasingly common in cancer treatment, and companion diagnostic tests assist oncologists in selecting patients who may benefit from these targeted treatments,” said Richard Pazdur, M.D., director of the FDA’s Oncology Center of Excellence and acting director of the Office of Hematology and Oncology Products in the FDA’s Center for Drug Evaluation and Research. “For this approval, we employed some of our newer regulatory tools to streamline reviews without compromising the quality of our assessment. This drug is the first novel drug approved under the Real-Time Oncology Review pilot program. We also used the updated Assessment Aid, a multidisciplinary review template that helps focus our written review on critical thinking and consistency and reduces time spent on administrative tasks.”

Metastatic breast cancer is breast cancer that has spread beyond the breast to other organs in the body (most often the bones, lungs, liver or brain). When breast cancer is hormone-receptor positive, patients may be treated with anti-hormonal treatment (also called endocrine therapy), alone or in combination with other medicines, or chemotherapy.

The efficacy of Piqray was studied in the SOLAR-1 trial, a randomized trial of 572 postmenopausal women and men with HR-positive, HER2-negative, advanced or metastatic breast cancer whose cancer had progressed while on or after receiving an aromatase inhibitor. Results from the trial showed the addition of Piqray to fulvestrant significantly prolonged progression- free survival (median of 11 months vs. 5.7 months) in patients whose tumors had a PIK3CA mutation.

Common side effects of Piqray are high blood sugar levels, increase in creatinine, diarrhea, rash, decrease in lymphocyte count in the blood, elevated liver enzymes, nausea, fatigue, low red blood cell count, increase in lipase (enzymes released by the pancreas), decreased appetite, stomatitis, vomiting, weight loss, low calcium levels, aPTT prolonged (blood clotting taking longer to occur than it should), and hair loss.

Health care professionals are advised to monitor patients taking Piqray for severe hypersensitivity reactions (intolerance). Patients are warned of potentially severe skin reactions (rashes that may result in peeling and blistering of skin or mucous membranes like the lips and gums). Health care professionals are advised not to initiate treatment in patients with a history of severe skin reactions such as Stevens-Johnson Syndrome, erythema multiforme, or toxic epidermal necrolysis. Patients on Piqray have reported severe hyperglycemia (high blood sugar), and the safety of Piqray in patients with Type 1 or uncontrolled Type 2 diabetes has not been established. Before initiating treatment with Piqray, health care professionals are advised to check fasting glucose and HbA1c, and to optimize glycemic control. Patients should be monitored for pneumonitis/interstitial lung disease (inflammation of lung tissue) and diarrhea during treatment. Piqray must be dispensed with a patient Medication Guide that describes important information about the drug’s uses and risks.

Piqray is the first new drug application (NDA) for a new molecular entity approved under the Real-Time Oncology Review (RTOR) pilot program, which permits the FDA to begin analyzing key efficacy and safety datasets prior to the official submission of an application, allowing the review team to begin their review and communicate with the applicant earlier. Piqray also used the updated Assessment Aid (AAid), a multidisciplinary review template intended to focus the FDA’s written review on critical thinking and consistency and reduce time spent on administrative tasks. With these two pilot programs, today’s approval of Piqray comes approximately three months ahead of the Prescription Drug User Fee Act (PDUFA) VI deadline of August 18, 2019.

The FDA granted this application Priority Review designation. The FDA granted approval of Piqray to Novartis. The FDA granted approval of the therascreen PIK3CA RGQ PCR Kit to QIAGEN Manchester, Ltd.

https://www.fda.gov/news-events/press-announcements/fda-approves-first-pi3k-inhibitor-breast-cancer?utm_campaign=052419_PR_FDA%20approves%20first%20PI3K%20inhibitor%20for%20breast%20cancer&utm_medium=email&utm_source=Eloqua

 

Alpelisib

(2S)-1-N-[4-methyl-5-[2-(1,1,1-trifluoro-2-methylpropan-2-yl)pyridin-4-yl]-1,3-thiazol-2-yl]pyrrolidine-1,2-dicarboxamide

PDT PAT WO 2010/029082

CHEMICAL NAMES: Alpelisib; CAS 1217486-61-7; BYL-719; BYL719; UNII-08W5N2C97Q; BYL 719
MOLECULAR FORMULA: C19H22F3N5O2S
MOLECULAR WEIGHT: 441.473 g/mol
  1. alpelisib
  2. 1217486-61-7
  3. BYL-719
  4. BYL719
  5. UNII-08W5N2C97Q
  6. BYL 719
  7. Alpelisib (BYL719)
  8. (S)-N1-(4-Methyl-5-(2-(1,1,1-trifluoro-2-methylpropan-2-yl)pyridin-4-yl)thiazol-2-yl)pyrrolidine-1,2-dicarboxamide
  9. NVP-BYL719

Alpelisib is an orally bioavailable phosphatidylinositol 3-kinase (PI3K) inhibitor with potential antineoplastic activity. Alpelisib specifically inhibits PI3K in the PI3K/AKT kinase (or protein kinase B) signaling pathway, thereby inhibiting the activation of the PI3K signaling pathway. This may result in inhibition of tumor cell growth and survival in susceptible tumor cell populations. Activation of the PI3K signaling pathway is frequently associated with tumorigenesis. Dysregulated PI3K signaling may contribute to tumor resistance to a variety of antineoplastic agents.

Alpelisib has been used in trials studying the treatment and basic science of Neoplasms, Solid Tumors, BREAST CANCER, 3rd Line GIST, and Rectal Cancer, among others.

 

SYN 2

POLYMORPHS

https://patents.google.com/patent/WO2012175522A1/en

(S)-pyrrolidine-l,2-dicarboxylic acid 2-amide l-(4-methyl-5-[2-(2,2,2-trifluoro-l,l- dimethyl-ethyl)-pyridin-4-yl]-thiazol-2-yl)-amidei hereafter referred to as compound I,

is an alpha-selective phosphatidylinositol 3 -kinase (PI3K) inhibitor. Compound I was originally described in WO 2010/029082, wherein the synthesis of its free base form was described. There is a need for additional solid forms of compound I, for use in drug substance and drug product development. It has been found that new solid forms of compound I can be prepared as one or more polymorph forms, including solvate forms. These polymorph forms exhibit new physical properties that may be exploited in order to obtain new pharmacological properties, and that may be utilized in drug substance and drug product development. Summary of the Invention

In one aspect, provided herein is a crystalline form of the compound of formula I, or a solvate of the crystalline form of the compound of formula I, or a salt of the crystalline form of the compound of formula I, or a solvate of a salt of the crystalline form of the compound of formula I. In one embodiment, the crystalline form of the compound of formula I has the polymorph form SA, SB, Sc, or SD.

In another aspect, provided herein is a pharmaceutical composition comprising a crystalline compound of formula I. In one embodiment of the pharmaceutical composition, the crystalline compound of formula I has the polymorph form SA, SB,Sc, or So.

In another aspect, provided herein is a method for the treatment of disorders mediated by PI3K, comprising administering to a patient in need of such treatment an effective amount of a crystalline compound of formula I, particularly SA, SB, SC,or SD .

In yet another aspect, provided herein is the use of a crystalline compound of formula I, particularly SA, SB, SC, or SD, for the preparation of a medicament for the treatment of disorders mediated by PI3K.

 

Source: https://newdrugapprovals.org/?s=alpelisib&submit=

 

Pharmacology and Toxicology from drugbank.ca

Indication

Alpelisib is indicated in combination with fulvestrant to treat postmenopausal women, and men, with advanced or metastatic breast cancer.Label This cancer must be hormone receptor (HR)-positive, human epidermal growth factor receptor 2 (HER2)-negative, and PIK3CA­ mutated.Label The cancer must be detected by an FDA-approved test following progression on or after an endocrine-based regimen.Label

Associated Conditions

Contraindications & Blackbox Warnings

Learn about our commercial Contraindications & Blackbox Warnings data.

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Pharmacodynamics

Alpelisib does not prolong the QTcF interval.Label Patients taking alpelisib experience a dose dependent benefit from treatment with a 51% advantage of a 200mg daily dose over a 100mg dose and a 22% advantage of 300mg once daily over 150mg twice daily.6 This suggests patients requiring a lower dose may benefit from twice daily dosing.6

Mechanism of action

Phosphatidylinositol-3-kinase-α (PI3Kα) is responsible for cell proliferation in response to growth factor-tyrosine kinase pathway activation.3 In some cancers PI3Kα’s p110α catalytic subunit is mutated making it hyperactive.3 Alpelisib inhibits (PI3K), with the highest specificity for PI3Kα.Label

TARGET ACTIONS ORGANISM
APhosphatidylinositol 4,5-bisphosphate 3-kinase catalytic subunit alpha isoform inhibitor Humans

Absorption

Alpelisib reached a peak concentration in plasma of 1320±912ng/mL after 2 hours.4 Alpelisib has an AUClast of 11,100±3760h ng/mL and an AUCINF of 11,100±3770h ng/mL.4 A large, high fat meal increases the AUC by 73% and Cmax by 84% while a small, low fat meal increases the AUC by 77% and Cmax by 145%.Label

Volume of distribution

The apparent volume of distribution at steady state is 114L.Label

Protein binding

Alpelisib is 89% protein bound.Label

Metabolism

Alpelisib is metabolized by hydrolysis reactions to form the primary metabolite.Label It is also metabolized by CYP3A4.Label The full metabolism of Alpelisib has yet to be determined but a series of reactions have been proposed.4,5 The main metabolic reaction is the substitution of an amine group on alpelisib for a hydroxyl group to form a metabolite known as M44,5 or BZG791.Label Alpelisib can also be glucuronidated to form the M1 and M12 metabolites.4,5

Hover over products below to view reaction partners

Route of elimination

36% of an oral dose is eliminated as unchanged drug in the feces and 32% as the primary metabolite BZG791 in the feces.Label 2% of an oral dose is eliminated in the urine as unchanged drug and 7.1% as the primary metabolite BZG791.Label In total 81% of an oral dose is eliminated in the feces and 14% is eliminated in the urine.Label

Half-life

The mean half life of alprelisib is 8 to 9 hours.Label

Clearance

The mean apparent oral clearance was 39.0L/h.4 The predicted clearance is 9.2L/hr under fed conditions.Label

Adverse Effects

Learn about our commercial Adverse Effects data.

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Toxicity

LD50 and Overdose

Patients experiencing an overdose may present with hyperglycemia, nausea, asthenia, and rash.Label There is no antidote for an overdose of alpelisib so patients should be treated symptomatically.Label Data regarding an LD50 is not readily available.MSDS In clinical trials, patients were given doses of up to 450mg once daily.Label

Pregnancy, Lactation, and Fertility

Following administration in rats and rabbits during organogenesis, adverse effects on the reproductive system, such as embryo-fetal mortality, reduced fetal weights, and increased incidences of fetal malformations, were observed.Label Based on these findings of animals studies and its mechanism of action, it is proposed that alpelisib may cause embryo-fetal toxicity when administered to pregnant patients.Label There is no data available regarding the presence of alpelisib in breast milk so breast feeding mothers are advised not to breastfeed while taking this medication and for 1 week after their last dose.Label Based on animal studies, alpelisib may impair fertility of humans.Label

Carcinogenicity and Mutagenicity

Studies of carcinogenicity have yet to be performed.Label Alpelisib has not been found to be mutagenic in the Ames test.Label It is not aneugenic, clastogenic, or genotoxic in further assays.Label

Affected organisms

Not Available

Pathways

Not Available

Pharmacogenomic Effects/ADRs 

 

Not Available

 

Source: https://www.drugbank.ca/drugs/DB12015

References

  1. Yuan TL, Cantley LC: PI3K pathway alterations in cancer: variations on a theme. Oncogene 2008, 27(41):5497-5510.
  2. Toker A: Double trouble for cancer gene. Science 2019, 366(6466):685-686.
  3. Vasan N, Razavi P, Johnson JL, Shao H, Shah H, Antoine A, Ladewig E, Gorelick A, Lin TY, Toska E et al: Double PIK3CA mutations in cis increase oncogenicity and sensitivity to PI3Kalpha inhibitors. Science 2019, 366(6466):714-723.

 

 

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Systems Biology analysis of Transcription Networks, Artificial Intelligence, and High-End Computing Coming to Fruition in Personalized Oncology

Curator: Stephen J. Williams, Ph.D.

In the June 2020 issue of the journal Science, writer Roxanne Khamsi has an interesting article “Computing Cancer’s Weak Spots; An algorithm to unmask tumors’ molecular linchpins is tested in patients”[1], describing some early successes in the incorporation of cancer genome sequencing in conjunction with artificial intelligence algorithms toward a personalized clinical treatment decision for various tumor types.  In 2016, oncologists Amy Tiersten collaborated with systems biologist Andrea Califano and cell biologist Jose Silva at Mount Sinai Hospital to develop a systems biology approach to determine that the drug ruxolitinib, a STAT3 inhibitor, would be effective for one of her patient’s aggressively recurring, Herceptin-resistant breast tumor.  Dr. Califano, instead of defining networks of driver mutations, focused on identifying a few transcription factors that act as ‘linchpins’ or master controllers of transcriptional networks withing tumor cells, and in doing so hoping to, in essence, ‘bottleneck’ the transcriptional machinery of potential oncogenic products. As Dr. Castilano states

“targeting those master regulators and you will stop cancer in its tracks, no matter what mutation initially caused it.”

It is important to note that this approach also relies on the ability to sequence tumors  by RNA-seq to determine the underlying mutations which alter which master regulators are pertinent in any one tumor.  And given the wide tumor heterogeneity in tumor samples, this sequencing effort may have to involve multiple biopsies (as discussed in earlier posts on tumor heterogeneity in renal cancer).

As stated in the article, Califano co-founded a company called Darwin-Health in 2015 to guide doctors by identifying the key transcription factors in a patient’s tumor and suggesting personalized therapeutics to those identified molecular targets (OncoTarget™).  He had collaborated with the Jackson Laboratory and most recently Columbia University to conduct a $15 million 3000 patient clinical trial.  This was a bit of a stretch from his initial training as a physicist and, in 1986, IBM hired him for some artificial intelligence projects.  He then landed in 2003 at Columbia and has been working on identifying these transcriptional nodes that govern cancer survival and tumorigenicity.  Dr. Califano had figured that the number of genetic mutations which potentially could be drivers were too vast:

A 2018 study which analyzed more than 9000 tumor samples reported over 1.5 million mutations[2]

and impossible to develop therapeutics against.  He reasoned that you would just have to identify the common connections between these pathways or transcriptional nodes and termed them master regulators.

A Pan-Cancer Analysis of Enhancer Expression in Nearly 9000 Patient Samples

Chen H, Li C, Peng X, et al. Cell. 2018;173(2):386-399.e12.

Abstract

The role of enhancers, a key class of non-coding regulatory DNA elements, in cancer development has increasingly been appreciated. Here, we present the detection and characterization of a large number of expressed enhancers in a genome-wide analysis of 8928 tumor samples across 33 cancer types using TCGA RNA-seq data. Compared with matched normal tissues, global enhancer activation was observed in most cancers. Across cancer types, global enhancer activity was positively associated with aneuploidy, but not mutation load, suggesting a hypothesis centered on “chromatin-state” to explain their interplay. Integrating eQTL, mRNA co-expression, and Hi-C data analysis, we developed a computational method to infer causal enhancer-gene interactions, revealing enhancers of clinically actionable genes. Having identified an enhancer ∼140 kb downstream of PD-L1, a major immunotherapy target, we validated it experimentally. This study provides a systematic view of enhancer activity in diverse tumor contexts and suggests the clinical implications of enhancers.

 

A diagram of how concentrating on these transcriptional linchpins or nodes may be more therapeutically advantageous as only one pharmacologic agent is needed versus multiple agents to inhibit the various upstream pathways:

 

 

From: Khamsi R: Computing cancer’s weak spots. Science 2020, 368(6496):1174-1177.

 

VIPER Algorithm (Virtual Inference of Protein activity by Enriched Regulon Analysis)

The algorithm that Califano and DarwinHealth developed is a systems biology approach using a tumor’s RNASeq data to determine controlling nodes of transcription.  They have recently used the VIPER algorithm to look at RNA-Seq data from more than 10,000 tumor samples from TCGA and identified 407 transcription factor genes that acted as these linchpins across all tumor types.  Only 20 to 25 of  them were implicated in just one tumor type so these potential nodes are common in many forms of cancer.

Other institutions like the Cold Spring Harbor Laboratories have been using VIPER in their patient tumor analysis.  Linchpins for other tumor types have been found.  For instance, VIPER identified transcription factors IKZF1 and IKF3 as linchpins in multiple myeloma.  But currently approved therapeutics are hard to come by for targets with are transcription factors, as most pharma has concentrated on inhibiting an easier target like kinases and their associated activity.  In general, developing transcription factor inhibitors in more difficult an undertaking for multiple reasons.

Network-based inference of protein activity helps functionalize the genetic landscape of cancer. Alvarez MJ, Shen Y, Giorgi FM, Lachmann A, Ding BB, Ye BH, Califano A:. Nature genetics 2016, 48(8):838-847 [3]

Abstract

Identifying the multiple dysregulated oncoproteins that contribute to tumorigenesis in a given patient is crucial for developing personalized treatment plans. However, accurate inference of aberrant protein activity in biological samples is still challenging as genetic alterations are only partially predictive and direct measurements of protein activity are generally not feasible. To address this problem we introduce and experimentally validate a new algorithm, VIPER (Virtual Inference of Protein-activity by Enriched Regulon analysis), for the accurate assessment of protein activity from gene expression data. We use VIPER to evaluate the functional relevance of genetic alterations in regulatory proteins across all TCGA samples. In addition to accurately inferring aberrant protein activity induced by established mutations, we also identify a significant fraction of tumors with aberrant activity of druggable oncoproteins—despite a lack of mutations, and vice-versa. In vitro assays confirmed that VIPER-inferred protein activity outperforms mutational analysis in predicting sensitivity to targeted inhibitors.

 

 

 

 

Figure 1 

Schematic overview of the VIPER algorithm From: Alvarez MJ, Shen Y, Giorgi FM, Lachmann A, Ding BB, Ye BH, Califano A: Functional characterization of somatic mutations in cancer using network-based inference of protein activity. Nature genetics 2016, 48(8):838-847.

(a) Molecular layers profiled by different technologies. Transcriptomics measures steady-state mRNA levels; Proteomics quantifies protein levels, including some defined post-translational isoforms; VIPER infers protein activity based on the protein’s regulon, reflecting the abundance of the active protein isoform, including post-translational modifications, proper subcellular localization and interaction with co-factors. (b) Representation of VIPER workflow. A regulatory model is generated from ARACNe-inferred context-specific interactome and Mode of Regulation computed from the correlation between regulator and target genes. Single-sample gene expression signatures are computed from genome-wide expression data, and transformed into regulatory protein activity profiles by the aREA algorithm. (c) Three possible scenarios for the aREA analysis, including increased, decreased or no change in protein activity. The gene expression signature and its absolute value (|GES|) are indicated by color scale bars, induced and repressed target genes according to the regulatory model are indicated by blue and red vertical lines. (d) Pleiotropy Correction is performed by evaluating whether the enrichment of a given regulon (R4) is driven by genes co-regulated by a second regulator (R4∩R1). (e) Benchmark results for VIPER analysis based on multiple-samples gene expression signatures (msVIPER) and single-sample gene expression signatures (VIPER). Boxplots show the accuracy (relative rank for the silenced protein), and the specificity (fraction of proteins inferred as differentially active at p < 0.05) for the 6 benchmark experiments (see Table 2). Different colors indicate different implementations of the aREA algorithm, including 2-tail (2T) and 3-tail (3T), Interaction Confidence (IC) and Pleiotropy Correction (PC).

 Other articles from Andrea Califano on VIPER algorithm in cancer include:

Resistance to neoadjuvant chemotherapy in triple-negative breast cancer mediated by a reversible drug-tolerant state.

Echeverria GV, Ge Z, Seth S, Zhang X, Jeter-Jones S, Zhou X, Cai S, Tu Y, McCoy A, Peoples M, Sun Y, Qiu H, Chang Q, Bristow C, Carugo A, Shao J, Ma X, Harris A, Mundi P, Lau R, Ramamoorthy V, Wu Y, Alvarez MJ, Califano A, Moulder SL, Symmans WF, Marszalek JR, Heffernan TP, Chang JT, Piwnica-Worms H.Sci Transl Med. 2019 Apr 17;11(488):eaav0936. doi: 10.1126/scitranslmed.aav0936.PMID: 30996079

An Integrated Systems Biology Approach Identifies TRIM25 as a Key Determinant of Breast Cancer Metastasis.

Walsh LA, Alvarez MJ, Sabio EY, Reyngold M, Makarov V, Mukherjee S, Lee KW, Desrichard A, Turcan Ş, Dalin MG, Rajasekhar VK, Chen S, Vahdat LT, Califano A, Chan TA.Cell Rep. 2017 Aug 15;20(7):1623-1640. doi: 10.1016/j.celrep.2017.07.052.PMID: 28813674

Inhibition of the autocrine IL-6-JAK2-STAT3-calprotectin axis as targeted therapy for HR-/HER2+ breast cancers.

Rodriguez-Barrueco R, Yu J, Saucedo-Cuevas LP, Olivan M, Llobet-Navas D, Putcha P, Castro V, Murga-Penas EM, Collazo-Lorduy A, Castillo-Martin M, Alvarez M, Cordon-Cardo C, Kalinsky K, Maurer M, Califano A, Silva JM.Genes Dev. 2015 Aug 1;29(15):1631-48. doi: 10.1101/gad.262642.115. Epub 2015 Jul 30.PMID: 26227964

Master regulators used as breast cancer metastasis classifier.

Lim WK, Lyashenko E, Califano A.Pac Symp Biocomput. 2009:504-15.PMID: 19209726 Free

 

Additional References

 

  1. Khamsi R: Computing cancer’s weak spots. Science 2020, 368(6496):1174-1177.
  2. Chen H, Li C, Peng X, Zhou Z, Weinstein JN, Liang H: A Pan-Cancer Analysis of Enhancer Expression in Nearly 9000 Patient Samples. Cell 2018, 173(2):386-399 e312.
  3. Alvarez MJ, Shen Y, Giorgi FM, Lachmann A, Ding BB, Ye BH, Califano A: Functional characterization of somatic mutations in cancer using network-based inference of protein activity. Nature genetics 2016, 48(8):838-847.

 

Other articles of Note on this Open Access Online Journal Include:

Issues in Personalized Medicine in Cancer: Intratumor Heterogeneity and Branched Evolution Revealed by Multiregion Sequencing

 

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Cholesterol-busting gut bacteria affect people’s cardiac health

Reporter: Irina Robu, PhD

Scientists at Broad Institute of MIT and Harvard University, has discovered a group a gut bacterium that can metabolize enough cholesterol to affect metabolism. Their study in Cell Host and Microbe, found that bacteria in the intestines have lower cholesterol levels in their blood. Cholesterol is a key biological molecule that functions as a structural component of all animal cell membranes and is a precursor of steroid hormones, vitamin D, and bile acids. Two main sources of cholesterol are thought to influence concentrations of this metabolite in serum: endogenous cholesterol synthesized in the liver and exogenous cholesterol derived from dietary components of animal origin.

The study shows a roadmap of how enzymes and microbial genes can manipulate metabolism and impact human health. The concept that bacteria can metabolize cholesterol is been known for a long time, but not enough has been known of which species of bacteria was doing this. However, isolating cholesterol metabolizing bacteria and growing them in the lab proved to be difficult.

The idea that bacteria can metabolize cholesterol isn’t a new one; in the early 1900s, scientists reported the existence of bacteria that could chemically transform cholesterol into a compound called coprostanol. Coprostanol-generating bacteria have been found in the guts of rats, baboons, pigs, and even humans, but the biology of these bacteria was poorly understood.

The scientists genetically engineered bacteria in the lab to produce genetically engineered bacteria in the lab to produce four enzymes of interest. Yet, they focused on one gene named Intestinal Stool Metabolism (IsmA) that could metabolize cholesterol. Furthermore, individuals with the IsmA gene had, on average, cholesterol levels in the blood that were 2.7 mg/dL lower than those without any copies of the IsmA genes in their microbiomes. This is a larger average effect on blood cholesterol than human genes such as HMGCR and PCSK9, which are known to alter a person’s risk of high cholesterol levels and are targeted by some FDA-approved cholesterol drugs.

SOURCE

https://www.broadinstitute.org/news/cholesterol-busting-gut-bacteria-may-affect-people%E2%80%99s-cardiac-health

 

 

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Live Conference Coverage AACR 2020 in Real Time: Monday June 22, 2020 Late Day Sessions

 

Reporter: Stephen J. Williams, PhD

 

Follow Live in Real Time using

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@pharma_BI

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Register for FREE at https://www.aacr.org/

 

AACR VIRTUAL ANNUAL MEETING II

 

June 22-24: Free Registration for AACR Members, the Cancer Community, and the Public
This virtual meeting will feature more than 120 sessions and 4,000 e-posters, including sessions on cancer health disparities and the impact of COVID-19 on clinical trials

 

This Virtual Meeting is Part II of the AACR Annual Meeting.  Part I was held online in April and was centered only on clinical findings.  This Part II of the virtual meeting will contain all the Sessions and Abstracts pertaining to basic and translational cancer research as well as clinical trial findings.

 

REGISTER NOW

 

 

 

Virtual Educational Session

Prevention Research, Science Policy, Epidemiology, Survivorship

Carcinogens at Home: Science and Pathways to Prevention

Chemicals known to cause cancer are used and released to the environment in large volumes, exposing people where they live, work, play, and go to school. The science establishing an important role for such exposures in the development of cancers continues to strengthen, yet cancer prevention researchers are largely unfamiliar with the data drawn upon in identifying carcinogens and making decisions about their use. Characterizing and reducing harmful exposures and accelerating the devel

Julia Brody, Kathryn Z. Guyton, Polly J. Hoppin, Bill Walsh, Mary H. Ward

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Monday, June 22

1:30 PM – 3:30 PM EDT

Virtual Educational Session

Tumor Biology, Molecular and Cellular Biology/Genetics, Clinical Research Excluding Trials

EMT Still Matters: Let’s Explore! – Dedicated to the Memory of Isaiah J. Fidler

During carcinoma progression, initially benign epithelial cells acquire the ability to invade locally and disseminate to distant tissues by activating epithelial-mesenchymal transition (EMT). EMT is a cellular process during which epithelial cells lose their epithelial features and acquire mesenchymal phenotypes and behavior. Growing evidence supports the notion that EMT programs during tumor progression are usually activated to various extents and often partial and reversible, thus pr

Jean-Paul Thiery, Heide L Ford, Jing Yang, Geert Berx

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Monday, June 22

1:30 PM – 3:00 PM EDT

Virtual Educational Session

Tumor Biology, Experimental and Molecular Therapeutics, Molecular and Cellular Biology/Genetics

One of These Things Is Not Like the Other: The Many Faces of Senescence in Cancer

Cellular senescence is a stable cell growth arrest that is broadly recognized to act as a barrier against tumorigenesis. Senescent cells acquire a senescence-associated secretory phenotype (SASP), a transcriptional response involving the secretion of inflammatory cytokines, immune modulators, and proteases that can shape the tumor microenvironment. The SASP can initially stimulate tumor immune surveillance and reinforce growth arrest. However, if senescent cells are not removed by the

Clemens A Schmitt, Andrea Alimonti, René Bernards

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Monday, June 22

1:30 PM – 3:00 PM EDT

Virtual Educational Session

Clinical Research Excluding Trials, Molecular and Cellular Biology/Genetics

Recent Advances in Applications of Cell-Free DNA

The focus of this educational session will be on recent developments in cell-free DNA (cfDNA) analysis that have the potential to impact the care of cancer patients. Tumors continually shed DNA into the circulation, where it can be detected as circulating tumor DNA (ctDNA). Analysis of ctDNA has become a routine part of care for a subset of patients with advanced malignancies. However, there are a number of exciting potential applications that have promising preliminary data but that h

Michael R Speicher, Maximilian Diehn, Aparna Parikh

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Monday, June 22

1:30 PM – 3:30 PM EDT

Virtual Methods Workshop

Clinical Research Excluding Trials, Clinical Trials, Experimental and Molecular Therapeutics, Molecular and Cellular Biology/Genetics

Translating Genetics and Genomics to the Clinic and Population

This session will describe how advances in understanding cancer genomes and in genetic testing technologies are being translated to the clinic. The speakers will illustrate the clinical impact of genomic discoveries for diagnostics and treatment of common tumor types in adults and in children. Cutting-edge technologies for characterization of patient and tumor genomes will be described. New insights into the importance of patient factors for cancer risk and outcome, including predispos

Heather L. Hampel, Gordana Raca, Jaclyn Biegel, Jeffrey M Trent

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Monday, June 22

1:30 PM – 3:22 PM EDT

Virtual Educational Session

Regulatory Science and Policy, Drug Development, Epidemiology

Under-representation in Clinical Trials and the Implications for Drug Development

The U.S. Food and Drug Administration relies on data from clinical trials to determine whether medical products are safe and effective. Ideally, patients enrolled in those trials are representative of the population in which the product will be used if approved, including people of different ages, races, ethnic groups, and genders. Unfortunately, with few patients enrolling in clinical trials, many groups are not well-represented in clinical trials. This session will explore challenges

Ajay K. Nooka, Nicole J. Gormley, Kenneth C Anderson, Ruben A. Mesa, Daniel J. George, Yelak Biru, RADM Richardae Araojo, Lola A. Fashoyin-Aje

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Monday, June 22

3:45 PM – 5:45 PM EDT

Virtual Educational Session

Cancer Chemistry

Targeted Protein Degradation: Target Validation Tools and Therapeutic Opportunity

This educational session will cover the exciting emerging field of targeted protein degradation. Key learning topics will include: 1. an introduction to the technology and its relevance to oncology; 2. PROTACS, degraders, and CELMoDs; 3. enzymology and protein-protein interactions in targeted protein degraders; 4. examples of differentiated biology due to degradation vs. inhibition; 5. how to address questions of specificity; and 6. how the field is approaching challenges in optimizing therapies

George Burslem, Mary Matyskiela, Lyn H. Jones, Stewart L Fisher, Andrew J Phillips

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Monday, June 22

3:45 PM – 5:45 PM EDT

Virtual Educational Session

Bioinformatics and Systems Biology, Experimental and Molecular Therapeutics, Drug Development, Molecular and Cellular Biology/Genetics

Obstacles and opportunities for protein degradation drug discovery

Lyn H. Jones
  • PROTACs ubiquitin mediated by E3 ligases;  first discovered by DeShaies and targeted to specific proteins
  • PROTACs used in drug discovery against a host of types of targets including kinases and membrane receptors
  • PROTACs can be modular but lack molecular structural activity relationships
  • can use chemical probes for target validation
  • four requirements: candidate exposure at site of action (for example lipophilicity for candidates needed to cross membranes and accumulate in lysosomes), target engagement (ternary occupancy as measured by FRET), functional pharmacology, relevant phenotype
  • PROTACs hijack the proteosomal degradation system

Proteolysis-targeting chimeras as therapeutics and tools for biological discovery

George Burslem
  • first PROTAC developed to coopt the VHL ubiquitin ligase system which degrades HIF1alpha but now modified for EREalpha
  • in screen for potential PROTACS there were compounds which bound high affinity but no degradation so phenotypic screening very important
  • when look at molecular dynamics can see where PROTAC can add additional protein protein interaction, verifed by site directed mutagenesis
  • able to target bcr-Abl
  • he says this is a rapidly expanding field because of all the new E3 ligase targets being discovered

Expanding the horizons of cereblon modulators

Mary Matyskiela

Translating cellular targeted protein degradation to in vivo models using an enzymology framework

Stewart L Fisher
  • new targeting compounds have an E3 ligase binding domain, a target binding domain and a linker domain
  • in vivo these compounds are very effective; BRD4 degraders good invitro and in vivo with little effect on body weight
  • degraders are essential activators of E3 ligases as these degraders bring targets in close proximity so activates a catalytic cycle of a multistep process (has now high turnover number)
  • in enzymatic pathway the degraders make a productive complex so instead of a kcat think of measuring a kprod or productivity of degraders linked up an E3 ligase
  • the degraders are also affecting the rebound protein synthesis; so Emax never to zero and see a small rebound of protein synthesis

 

Data-Driven Approaches for Choosing Combinatorial Therapies

Drug combinations remain the gold standard for treating cancer, as they significantly outperform single agents. However, due to the enormous size of drug combination space, it is virtually impossible to interrogate all possible combinations. This session will discuss approaches to identify novel combinations using both experimental and computational approaches. Speakers will discuss i) approaches to drug screening in cell lines, the impact of the microenvironment, and attempts to more

Bence Szalai, James E Korkola, Lisa Tucker-Kellogg, Jeffrey W Tyner

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Monday, June 22

3:45 PM – 5:21 PM EDT

Virtual Educational Session

Tumor Biology

Cancer Stem Cells and Therapeutic Resistance

Cancer stem cells are a subpopulation of cells with a high capacity for self-renewal, differentiation and resistance to therapy. In this session, we will define cancer stem cells, discuss cellular plasticity, interactions between cancer stem cells and the tumor microenvironment, and mechanisms that contribute to therapeutic resistance.

Robert S Kerbel, Dolores Hambardzumyan, Jennifer S. Yu

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Monday, June 22

3:45 PM – 5:45 PM EDT

Virtual Educational Session

Drug Development, Experimental and Molecular Therapeutics

Molecular Imaging in Cancer Research

This session will cover the fundamentals as well as the major advances made in the field of molecular imaging. Topics covered will include the basics for optical, nuclear, and ultrasound imaging; the pros and cons of each modality; and the recent translational advancements. Learning objectives include the fundamentals of each imaging modality, recent advances in the technology, the processes involved to translate an imaging agent from bench to bedside, and how molecular imaging can gui

Julie Sutcliffe, Summer L Gibbs, Mark D Pagel, Katherine W Ferrara

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Monday, June 22

3:45 PM – 5:45 PM EDT

Virtual Educational Session

Tumor Biology, Immunology, Experimental and Molecular Therapeutics, Drug Development

Tumor Endothelium: The Gatekeepers of Tumor Immune Surveillance

Tumor-associated endothelium is a gatekeeper that coordinates the entry and egress of innate and adaptive immune cells within the tumor microenvironment. This is achieved, in part, via the coordinated expression of chemokines and cell adhesion molecules on the endothelial cell surface that attract and retain circulating leukocytes. Crosstalk between adaptive immune cells and the tumor endothelium is therefore essential for tumor immune surveillance and the success of immune-based thera

Dai Fukumura, Maria M Steele, Wen Jiang, Andrew C Dudley

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Monday, June 22

3:45 PM – 5:45 PM EDT

Virtual Educational Session

Immunology, Experimental and Molecular Therapeutics

Novel Strategies in Cancer Immunotherapy: The Next Generation of Targets for Anticancer Immunotherapy

T-cell immunotherapy in the form of immune checkpoint blockade or cellular T-cell therapies has been tremendously successful in some types of cancer. This success has opened the door to consider what other modalities or types of immune cells can be harnessed for exert antitumor functions. In this session, experts in their respective fields will discuss topics including novel approaches in immunotherapy, including NK cells, macrophage, and viral oncotherapies.

Evanthia Galanis, Kerry S Campbell, Milan G Chheda, Jennifer L Guerriero

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Monday, June 22

3:45 PM – 5:45 PM EDT

Virtual Educational Session

Tumor Biology, Drug Development, Immunology, Clinical Research Excluding Trials

Benign Cells as Drivers of Cancer Progression: Fat and Beyond

Carcinomas develop metastases and resistance to therapy as a result of interaction with tumor microenvironment, composed of various nonmalignant cell types. Understanding the complexity and origins of tumor stromal cells is a prerequisite for development of effective treatments. The link between obesity and cancer progression has revealed the engagement of adipose stromal cells (ASC) and adipocytes from adjacent fat tissue. However, the molecular mechanisms through which they stimulate

Guojun Wu, Matteo Ligorio, Mikhail Kolonin, Maria T Diaz-Meco

DETAILS

Monday, June 22

3:45 PM – 5:45 PM EDT

Virtual Educational Session

Clinical Research Excluding Trials, Experimental and Molecular Therapeutics, Tumor Biology

Dharma Master Jiantai Symposium on Lung Cancer: Know Thy Organ – Lessons Learned from Lung and Pancreatic Cancer Research

The term “cancer” encompasses hundreds of distinct disease entities involving almost every possible site in the human body. Effectively interrogating cancer, either in animals models or human specimens, requires a deep understanding of the involved organ. This includes both the normal cellular constituents of the affected tissue as well as unique aspects of tissue-specific tumorigenesis. It is critical to “Know Thy Organ” when studying cancer. This session will focus on two of the most

Trudy G Oliver, Hossein Borghaei, Laura Delong Wood, Howard C Crawford

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Monday, June 22

3:45 PM – 5:45 PM EDT

Virtual Methods Workshop

Clinical Trials

Clinical Trial Design: Part 1: Novel Approaches and Methods in Clinical Trial Design

Good clinical trial design has always had to balance the competing interests of effectively and convincingly answering the question with the limitations imposed by scarce resources, complex logistics, and risks and potential benefits to participants. New targeted therapies, immuno-oncology, and novel combination treatments add new challenges on top of the old ones. This session will introduce these concerns and 1) suggest ways to consider what outcomes are relevant, 2) how we can best

Mary W. Redman, Nolan A. Wages, Susan G Hilsenbeck, Karyn A. Goodman

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Monday, June 22

3:45 PM – 5:45 PM EDT

Virtual Methods Workshop

Tumor Biology, Drug Development

High-Throughput Screens for Drivers of Progression and Resistance

The sequencing of human cancers now provides a landscape of the genetic alterations that occur in human cancer, and increasingly knowledge of somatic genetic alterations is becoming part of the evaluation of cancer patients. In some cases, this information leads directly to the selection of particular therapeutic approaches; however, we still lack the ability to decipher the significance of genetic alterations in many cancers. This session will focus on recent developments that permit the identification of molecular targets in specific cancers. This information, coupled with genomic characterization of cancer, will facilitate the development of new therapeutic agents and provide a path to implement precision cancer medicine to all patients.

William C Hahn, Mark A Dawson, Mariella Filbin, Michael Bassik

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Monday, June 22

3:45 PM – 5:15 PM EDT

Defining a cancer dependency map

William C Hahn

Introduction

William C Hahn

Genome-scale CRISPR screens in 3D spheroids identify cancer vulnerabilities

Michael Bassik

Utilizing single-cell RNAseq and CRISPR screens to target cancer stem cells in pediatric brain tumors

Mariella Filbin
  • many gliomas are defined by discreet mutational spectra that also discriminates based on age and site as well (for example many cortical tumors have mainly V600E Braf mutations while thalamus will be FGFR1
  • they did single cell RNAseq on needle biopsy from 7 gliomas which gave about 3500 high quality single cells; obtained full length RNA
  • tumors clustered mainly where the patient it came from but had stromal cell contamination probably so did a deconvolution?  Copy number variation showed which were tumor cells and did principle component analysis
  • it seems they used a human glioma model as training set
  • identified a stem cell like glioma cell so concentrated on the genes altered in these for translational studies
  • developed multiple PDX models from patients
  • PDX transcriptome closest to patient transcriptome but organoid grown in serum free very close while organoids grown in serum very distinct transcriptome
  • developed a CRISPR barcoded library to determine genes for survival genes
  • pulled out BMI1  and EZH2 (polycomb complex proteins) as good targets

Virtual Methods Workshop

Prevention Research, Survivorship, Clinical Research Excluding Trials, Epidemiology

Implementation Science Methods for Cancer Prevention and Control in Diverse Populations: Integration of Implementation Science Methods in Care Settings

Through this Education Session we will use examples from ongoing research to provide an overview of implementation science approaches to cancer prevention and control research. We draw on examples to highlight study design approaches, research methods, and real-world solutions when applying implementation science to achieve health equity. Approaches to defining change in the care setting and measuring sustained changes are also emphasized. Using real examples of patient navigation prog

Graham A Colditz, Sanja Percac-Lima, Nathalie Huguet

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Monday, June 22

3:45 PM – 5:30 PM EDT

Virtual Educational Session

Regulatory Science and Policy, Epidemiology

COVID-19 and Cancer: Guidance for Clinical Trial Conduct and Considerations for RWE

This session will consider the use of real-world evidence in the context of oncology clinical trials affected by the COVID-19 pandemic. Key aspects of the FDA’s recent “Guidance on Conduct of Clinical Trials of Medical Products of Medical Products during COVID-19 Public Health Emergency” will be discussed, including telemedicine, accounting for missing data, obtaining laboratory tests and images locally, using remote informed consent procedures, and additional considerations for contin

Wendy Rubinstein, Paul G. Kluetz, Amy P. Abernethy, Jonathan Hirsch, C.K. Wang

 

 

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Important but Unseen Human Embryo Developmental Stages Mimicked in Lab

 

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

 

Scientists have created embryo-like structures that mimic a crucial yet not much known stage of human development. The structures, created from stem cells and called gastruloids, are the first to form a 3D assembly that lays out how the body will take shape. The gastruloids developed rudimentary components of a heart and nervous system, but lacked the components to form a brain and other cell types that would make them capable of becoming a viable fetus.

Human embryos take a momentous leap in their third week, when the largely homogeneous ball of cells starts to differentiate and develop specific characteristics of the body parts they will become, a process known as gastrulation. During this process, the embryo elongates and lays down a body plan with a head and tail, often called the head-to-tail axis. But scientists have never seen this process live in action. That is partly because many countries have regulations that stop embryos from being grown in the laboratory for research beyond 14 days.

Over the past years, several research groups have cultured embryonic stem-cell structures that model when cells start to differentiate. The latest model developed at the University of Cambridge, UK and their collaborators in the Netherlands, Showed for the first time what happens when the blueprint for the body’s development is laid out, around 18–21 days after conception. Genetic analysis showed that the cells formed were those that would eventually go on to form muscles in the trunk, vertebrae, heart and other organs.

If everything is done properly, the cells develop into 3D structures on their own — and then spontaneously mimic the gastrulation process. Although they display certain key features of a 21-day-old embryo, the gastruloids reach that stage after just 72 hours and survive for maximum 4 days before collapsing. Scientists will probably use the model to make structures that are even more realistic representations of early development.

The model could help scientists to understand the role of genetics and environmental factors in different disorders. The artificial structures make it possible to avoid ethical concerns about doing research on human embryos. But as the structures become more advanced and life-like, there may be ethical restrictions.

SOURCE

David Cyranoski

References for Original Study

https://www.nature.com/articles/d41586-020-01757-z?utm_source=Nature+Briefing

 

Other References:

https://pubmed.ncbi.nlm.nih.gov/32528178/

https://pubmed.ncbi.nlm.nih.gov/22804578/

https://pubmed.ncbi.nlm.nih.gov/24973948/

https://pubmed.ncbi.nlm.nih.gov/27419872/

https://pubmed.ncbi.nlm.nih.gov/28179190/

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