Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Researchers identify target for cancer drugs

18.02.2005


For nearly a decade, scientists have been trying to fully understand a particular communication pathway inside of cells that contributes to many malignant brain and prostate cancers. While scientists have identified elements of this pathway, other key components have remained a mystery. Researchers at Whitehead Institute now have discovered a missing puzzle piece, a finding that may present drug makers with a significant new cancer target.



"We believe that we have identified a component that researchers have been looking for since 1996," says Whitehead Associate Member David Sabatini, who is also an Assistant Professor of Biology at MIT.

At the heart of this new research is a protein called Akt, an important player in the regulation of cell division and survival. Abnormally high activation of Akt has long been implicated in a variety of cancers. If Akt travels to the cell membrane, it is switched on and promotes cell division, often contributing to tumor growth as a result. However, as long as it stays within the cell cytoplasm, it remains relatively inactive. That’s because the tumor-suppressor protein PTEN keeps Akt in check by destroying lipids in the cell membrane that normally draw Akt to the surface. In a sense, PTEN keeps a leash on Akt and thus suppresses cell division.


But when PTEN is mutated and unable to function, Akt breaks free. It makes its way to the cell membrane where other proteins activate it, thereby enabling Akt to contribute to tumor growth. "When a cell loses PTEN through, say, a mutation, Akt goes gangbusters," says Sabatini.

The exact means by which Akt switches on when it reaches the cell membrane has only been partially understood. As a result, researchers have lacked a clear idea about how to prevent the process. However, in the February 18 issue of the journal Science, researchers from the Sabatini lab report on discovering an important missing piece of the activation process.

This missing component, a molecule called mTOR, is a protein that influences a cell’s ability to expand in size. mTOR has been widely studied as the target for the immunosuppressant drug rapamycin (in fact, mTOR is an acronym for "mammalian target of rapamycin"). In July of 2004, Dos Sarbassov, a scientist in Sabatini’s lab, discovered a new protein that mTOR interacts with called rictor, but he wasn’t yet sure of what these two proteins do together. In this latest paper, Sarbassov reports that when mTOR and rictor bind and form a complex, they help activate Akt by adding a phosphate group to a sequence of its amino acids (a process called "phosphorylation").

This process occurs not only in human cells but in other organisms such as the fruit fly. Finding this complex conserved in species as diverse as flies and humans supports the claim that the mTOR/rictor complex is indeed a missing piece of the puzzle.

According to Sarbassov, "If we find a molecule that can block the mTOR/rictor complex, then we may be able to prevent Akt from becoming active and contributing to tumor formation."

David Cameron | EurekAlert!
Further information:
http://www.wi.mit.edu

More articles from Life Sciences:

nachricht Scientists coax proteins to form synthetic structures with method that mimics nature
15.01.2019 | University of Texas at Austin

nachricht DNA library of apoid wasps published
15.01.2019 | Staatliche Naturwissenschaftliche Sammlungen Bayerns

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Nanocellulose for novel implants: Ears from the 3D-printer

Cellulose obtained from wood has amazing material properties. Empa researchers are now equipping the biodegradable material with additional functionalities to produce implants for cartilage diseases using 3D printing.

It all starts with an ear. Empa researcher Michael Hausmann removes the object shaped like a human ear from the 3D printer and explains:

Im Focus: Elucidating the Atomic Mechanism of Superlubricity

The phenomenon of so-called superlubricity is known, but so far the explanation at the atomic level has been missing: for example, how does extremely low friction occur in bearings? Researchers from the Fraunhofer Institutes IWM and IWS jointly deciphered a universal mechanism of superlubricity for certain diamond-like carbon layers in combination with organic lubricants. Based on this knowledge, it is now possible to formulate design rules for supra lubricating layer-lubricant combinations. The results are presented in an article in Nature Communications, volume 10.

One of the most important prerequisites for sustainable and environmentally friendly mobility is minimizing friction. Research and industry have been dedicated...

Im Focus: Mission completed – EU partners successfully test new technologies for space robots in Morocco

Just in time for Christmas, a Mars-analogue mission in Morocco, coordinated by the Robotics Innovation Center of the German Research Center for Artificial Intelligence (DFKI) as part of the SRC project FACILITATORS, has been successfully completed. SRC, the Strategic Research Cluster on Space Robotics Technologies, is a program of the European Union to support research and development in space technologies. From mid-November to mid-December 2018, a team of more than 30 scientists from 11 countries tested technologies for future exploration of Mars and Moon in the desert of the Maghreb state.

Close to the border with Algeria, the Erfoud region in Morocco – known to tourists for its impressive sand dunes – offered ideal conditions for the four-week...

Im Focus: Programming light on a chip

Research opens doors in photonic quantum information processing, optical signal processing and microwave photonics

Researchers from the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS) have developed a new integrated photonics platform that can...

Im Focus: Physicists uncover new competing state of matter in superconducting material

A team of experimentalists at the U.S. Department of Energy's Ames Laboratory and theoreticians at University of Alabama Birmingham discovered a remarkably long-lived new state of matter in an iron pnictide superconductor, which reveals a laser-induced formation of collective behaviors that compete with superconductivity.

"Superconductivity is a strange state of matter, in which the pairing of electrons makes them move faster," said Jigang Wang, Ames Laboratory physicist and...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

11th International Symposium: “Advanced Battery Power – Kraftwerk Batterie” Aachen, 3-4 April 2019

14.01.2019 | Event News

ICTM Conference 2019: Digitization emerges as an engineering trend for turbomachinery construction

12.12.2018 | Event News

New Plastics Economy Investor Forum - Meeting Point for Innovations

10.12.2018 | Event News

 
Latest News

Scientists coax proteins to form synthetic structures with method that mimics nature

15.01.2019 | Life Sciences

Next generation photonic memory devices are light-written, ultrafast and energy efficient

15.01.2019 | Information Technology

Viennese scientists develop promising new type of polymers

15.01.2019 | Materials Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>