Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Silent DNA architecture helps block cancer cell growth

13.06.2003


Researchers uncover new tumor suppression mechanism



Cancerous and precancerous cells can detect that they are abnormal and kill themselves, or remain alive indefinitely but cease proliferating, through two intrinsic processes called programmed cell death and cellular senescence. One goal of cancer chemotherapy is to help stimulate these potent antitumor processes.

Researchers at Cold Spring Harbor Laboratory on Long Island have recently shown that by locking cancer cells into a permanent state in which they remain alive but can no longer proliferate, cellular senescence contributes to successful outcomes following cancer therapy. Now, the same group has uncovered a precise molecular mechanism that helps trigger the "stop growing" response of cells. The study is published in the June 13 issue of the journal Cell.


"We think we have uncovered one reason why cancer cells can remain in limbo - alive but not proliferating - for very long periods of time. This long term suppression of cancer cell growth is an important antitumor response. Now that we have a handle on the precise mechanism of the response, we hope to ultimately find ways to harness it for treating cancer," says Scott Lowe, who led the study.

Lowe and his colleagues found that cellular senescence involves the tight packaging of specific regions of chromosomal DNA into an inactive or silent architecture called heterochromatin.

To distinguish these newly identified regions of specialized DNA architecture from previously known forms of heterochromatin, the researchers dubbed such regions senescence-associated heterochromatic foci, or SAHF. Importantly, the study establishes that genes contained in these chromosomal regions are switched on in proliferating cells, but are switched off or "silenced" during cellular senescence.

Moreover, the researchers showed that the formation of SAHF is mediated by the action of a well-known tumor suppressor protein called Rb. Interestingly, the study reveals that the formation of SAHF maps to genes known from previous studies to be switched off through the action of Rb.

The study provides the first detailed view of how the tumor suppressor Rb establishes regions of specialized DNA architecture in the cell. Because such architecture is extremely stable, the research may explain the irreversibility of the senescent state, namely, why cells rarely if ever start growing again once they senesce.

The scientists studied a form of cultured human cells called IMR90 cells, which are commonly used to study cellular senescence.

Lowe is a Professor of Cancer Research at Cold Spring Harbor Laboratory and Deputy Director of the Laboratory’s NCI-designated Basic Cancer Center. He was joined in the study by eight other scientists, including postdoctoral fellow and lead author of the study, Masashi Narita, and by CSHL Professors David Spector and Gregory Hannon.

Peter Sherwood | EurekAlert!
Further information:
http://www.cshl.org/

More articles from Health and Medicine:

nachricht World first: Massive thrombosis removed during early pregnancy
20.07.2017 | Universitätsspital Bern

nachricht Therapy of preterm birth in sight?
19.07.2017 | Universitätsspital Bern

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

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

Im Focus: Manipulating Electron Spins Without Loss of Information

Physicists have developed a new technique that uses electrical voltages to control the electron spin on a chip. The newly-developed method provides protection from spin decay, meaning that the contained information can be maintained and transmitted over comparatively large distances, as has been demonstrated by a team from the University of Basel’s Department of Physics and the Swiss Nanoscience Institute. The results have been published in Physical Review X.

For several years, researchers have been trying to use the spin of an electron to store and transmit information. The spin of each electron is always coupled...

Im Focus: The proton precisely weighted

What is the mass of a proton? Scientists from Germany and Japan successfully did an important step towards the most exact knowledge of this fundamental constant. By means of precision measurements on a single proton, they could improve the precision by a factor of three and also correct the existing value.

To determine the mass of a single proton still more accurate – a group of physicists led by Klaus Blaum and Sven Sturm of the Max Planck Institute for Nuclear...

Im Focus: On the way to a biological alternative

A bacterial enzyme enables reactions that open up alternatives to key industrial chemical processes

The research team of Prof. Dr. Oliver Einsle at the University of Freiburg's Institute of Biochemistry has long been exploring the functioning of nitrogenase....

Im Focus: The 1 trillion tonne iceberg

Larsen C Ice Shelf rift finally breaks through

A one trillion tonne iceberg - one of the biggest ever recorded -- has calved away from the Larsen C Ice Shelf in Antarctica, after a rift in the ice,...

Im Focus: Laser-cooled ions contribute to better understanding of friction

Physics supports biology: Researchers from PTB have developed a model system to investigate friction phenomena with atomic precision

Friction: what you want from car brakes, otherwise rather a nuisance. In any case, it is useful to know as precisely as possible how friction phenomena arise –...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

»We are bringing Additive Manufacturing to SMEs«

19.07.2017 | Event News

The technology with a feel for feelings

12.07.2017 | Event News

Leipzig HTP-Forum discusses "hydrothermal processes" as a key technology for a biobased economy

12.07.2017 | Event News

 
Latest News

Researchers create new technique for manipulating polarization of terahertz radiation

20.07.2017 | Information Technology

High-tech sensing illuminates concrete stress testing

20.07.2017 | Materials Sciences

First direct observation and measurement of ultra-fast moving vortices in superconductors

20.07.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>