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 Researchers release the brakes on the immune system
18.10.2017 | Rheinische Friedrich-Wilhelms-Universität Bonn

nachricht Norovirus evades immune system by hiding out in rare gut cells
12.10.2017 | University of Pennsylvania School of Medicine

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: Neutron star merger directly observed for the first time

University of Maryland researchers contribute to historic detection of gravitational waves and light created by event

On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...

Im Focus: Breaking: the first light from two neutron stars merging

Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.

Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....

Im Focus: Smart sensors for efficient processes

Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).

When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...

Im Focus: Cold molecules on collision course

Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.

How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...

Im Focus: Shrinking the proton again!

Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.

It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

3rd Symposium on Driving Simulation

23.10.2017 | Event News

ASEAN Member States discuss the future role of renewable energy

17.10.2017 | Event News

World Health Summit 2017: International experts set the course for the future of Global Health

10.10.2017 | Event News

 
Latest News

Did you know how many parts of your car require infrared heat?

23.10.2017 | Automotive Engineering

3rd Symposium on Driving Simulation

23.10.2017 | Event News

Terahertz spectroscopy goes nano

20.10.2017 | Information Technology

VideoLinks
B2B-VideoLinks
More VideoLinks >>>