Navigation Links
New understanding of why anti-cancer therapy stops working at a specific stage
Date:6/24/2013

Jerusalem, June 23, 2013 Researchers at the Hebrew University of Jerusalem and in California have achieved a breakthrough in understanding how and why a promising anti-cancer therapy has failed to achieve hoped-for success in killing tumor cells. Their work could lead to new insights into overcoming this impasse.

The problematic therapy investigated involves suppression of the protein mTOR (mammalian target Of Rapamycin). MTOR plays an important role in regulating how cells process molecular signals from their environment, and it is observed as strongly activated in many solid cancers.

Drug-induced suppression of mTOR has until now shown success in causing the death of cancer cells in the outer layers of cancerous tumors, but has been disappointing in clinical trials in dealing with the core of those tumors.

Reduced oxygen supply -- hypoxia -- is a near-universal feature of solid tumors that can alter how tumors respond to therapies. It was known that the behavior of mTOR signaling is influenced and altered by the condition of hypoxia, but the mechanism to explain this was unknown.

A research team, which included Prof. Emeritus Raphael D. Levine of the Institute of Chemistry at the Hebrew University of Jerusalem and researchers from the California Institute of Technology and the David Geffen School of Medicine at UCLA, investigated whether the influence of hypoxia on mTOR signaling in model brain cancer systems could explain the poor performance of mTOR drugs. Their work appeared in a recent article in the Proceedings of the National Academy of Sciences (PNAS) in the US.

For their investigation, they employed a new microchip technology that allowed them to measure the mTOR protein signaling network in individual cancer cells, and they interpreted the results using a new set of theoretical tools derived from the physical sciences. The combined approach permitted the simplification of an otherwise complex biological system.

They found that at a particular level of oxygen starvation (hypoxia) that is common in solid tumors, the mTOR signaling network switches between two sets of properties. At the switching point, the theoretical models predicted that mTOR would be intrinsically unresponsive to drugging.

Furthermore, the combined experiment and theory results indicated that the switch could be interpreted as a type of phase transition, which has not been previously observed in biological systems.

This phase transition is the point of the switch between the two signaling networks and happens very abruptly. The change in signaling means that the body of cells studied no longer responds in the way it did before. In the case of the tumor, the "drugging" of the mTOR ceases, meaning that the tumor is no longer inhibited.

These results have several implications. First, they may explain the poor clinical performance of mTOR inhibitors. Second, they indicate that certain complex biological behaviors, which often confound scientists who are seeking to find effective therapies for human diseases, may be understood by the effective application of experimental and theoretical tools derived from the physical sciences.


'/>"/>

Contact: Jerry Barach
jerryb@savion.huni.ac.il
972-258-82904
The Hebrew University of Jerusalem
Source:Eurekalert

Related medicine news :

1. Lumositys big data provides new approach to understanding human cognition
2. Researchers gain new molecular-level understanding of the brains recovery after stroke
3. United Benefit Advisors Offers Employee Guide to Understanding PPACA
4. Biolog’s Phenotype MicroArray Technology Unlocks Critical Clue in Understanding Autism
5. Tools for better understanding breast cancer stem cells
6. OnSomble, Inc. Partners with The Aroostook Medical Center to Enhance Nurse Understanding of the Professional Role
7. Law Firm Releases New Informational Graphic on the Basics of Understanding Medical Malpractice Cases
8. Study brings greater understanding of tumor growth mechanism
9. Such a Great Date, Why Hasn't He/She Called Yet? Dr. Bonnie Provides Tips on Making it Thur the Dating Stages and Understanding the Opposite Sex
10. Sherri Gastelum and Platinum Tax Defenders Offer 5 Tips on Understanding Health Care Tax Issues from the Affordable Care Act
11. Liver disease: Understanding it will enable the provision of better treatment
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:8/18/2017)... (PRWEB) , ... August 18, 2017 , ... Yisrayl Hawkins, Pastor and Overseer at The ... says will lift the veil on false teachings pertaining to the mother of the Savior ... teach, you see a far different picture of the role of this historical woman. ...
(Date:8/18/2017)... ... 2017 , ... “Our Mountains to Climb: A Journey of Love and Faith ... together through the faith they shared to overcome struggles in life. “Our Mountains to ... author, Barbara J. Corcoran, a retired teacher and happily married since 1999; the author’s ...
(Date:8/18/2017)... ... August 18, 2017 , ... “Depressed: Super Heroes of the ... to reflect upon the stories and the relevance these tales may have on the ... Jessica Linhart, a former special education teacher, Jessica spends much of her time enjoying ...
(Date:8/18/2017)... , ... August 18, 2017 , ... “Steve the Snake”: ... “Steve the Snake” is the creation of published author, Harold Flash Haskins Jr., a ... a Department of Defense police officer. , “I write moral-based short stories for children ...
(Date:8/17/2017)... ... August 17, 2017 , ... ... announces that it will feature the National Council for Therapeutic Recreation Certification (NCTRC), ... information. , Established in 1981, NCTRC is a non-profit, international organization dedicated to ...
Breaking Medicine News(10 mins):
(Date:7/27/2017)... July 27, 2017  West Pharmaceutical Services, Inc. (NYSE: ... for the second-quarter 2017 and updated financial guidance for ... Second-Quarter 2017 Highlights Reported net sales ... the prior-year quarter. Net sales at constant currency (organic) ... EPS was $0.51, compared to $0.60 in the prior-year ...
(Date:7/26/2017)... 2017  Radium Medical Aesthetics, a leading medical aesthetic clinic in ... by effectively addressing several skin conditions from the inside. ... and more fragile. The skin becomes more transparent due to the ... harmful UV rays from the sun contributes to aging skin, causing ... ...
(Date:7/26/2017)... The Galien Foundation announced today the 2017 11 ... Award Nominees. Counted among the global health innovation industry,s most ... technology product achievement that improves the human condition. ... be U.S. Food and Drug Administration (FDA) approved for market ... impact human health. Sales data are not considered by the ...
Breaking Medicine Technology: