Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Keeping cancer in check

06.05.2005


Penn researchers demonstrate that a metabolic enzyme works through the tumor-suppressor protein p53 to control cellular replication

Researchers at the University of Pennsylvania School of Medicine have identified in normal cells that a common metabolic enzyme, which acts as a rheostat of cellular conditions, also controls cell replication. This control is managed through p53, the much-studied protein implicated in many types of cancer. The discovery of the interaction between these two molecules may lead to new ways to fight cancer. First author Russell G. Jones, PhD, a postdoctoral fellow in the laboratory of senior author Craig Thompson, MD, at the Abramson Family Cancer Research Institute at Penn, and colleagues describe their findings in the most recent issue of Molecular Cell.
This work tests the novel notion that cancer cells co-opt cellular pathways that govern metabolism in order to proliferate beyond a cell’s normal means. Cancer cells have, by definition, a high metabolic rate and consume glucose at a high rate. One of the fundamental questions being tested in the Thompson lab is the importance of metabolism in cancer and investigating how cancer cells differ from normal cells, allowing them to survive and replicate. (Thompson is the Chair of Penn’s Department of Cancer Biology and Scientific Director of the Abramson Family Cancer Research Institute.) "We think that the enzyme interprets the energetic environment of the cell," explains Jones. "It senses the stress a cell sees – such as low oxygen, low glucose, or the presence of free radicals – and, from this, can induce a check on replication through p53, acting in effect as a tumor-suppressor."


For this study, the investigators looked at noncancerous mouse cells called fibroblasts to see how normal cells work and what they do physiologically when faced with an environmental challenge: in this case, low glucose levels, explains Jones. When the enzyme – called AMP-activated protein kinase (AMPK) – is turned on, it prevents cells from replicating. It acts as a sensor to detect energy levels in a cell. When the cell experiences energy-limiting conditions, which is typified by low glucose, it uses more energy than it produces and enters into an energy-deficit state. In essence, AMPK acts as a "fuel gauge," letting a cell know when glucose levels are dangerously low. When AMPK is activated by low glucose levels, it stops cells from replicating.

But how is p53 implicated? Normally p53 is activated in response to stress, and it stops a cell from replicating through a complicated set of biochemical steps. For example, if a cell is hit by radiation, enzymes called kinases activate p53, leading to inhibition of cell replication. "We found that cells without p53 due to a mutation would continue to proliferate under low glucose conditions, bypassing the AMPK checkpoint," says Jones. The lab is now doing follow-up studies and is finding that when AMPK is activated in a tumor cell that has no active p53, it still proliferates, escaping the AMPK checkpoint. This avenue of study may one day provide another approach to treating cancer, the researchers surmise.

Karen Kreeger | EurekAlert!
Further information:
http://www.uphs.upenn.edu

More articles from Life Sciences:

nachricht Not of Divided Mind
19.01.2017 | Hertie-Institut für klinische Hirnforschung (HIH)

nachricht CRISPR meets single-cell sequencing in new screening method
19.01.2017 | CeMM Forschungszentrum für Molekulare Medizin der Österreichischen Akademie der Wissenschaften

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Traffic jam in empty space

New success for Konstanz physicists in studying the quantum vacuum

An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...

Im Focus: How gut bacteria can make us ill

HZI researchers decipher infection mechanisms of Yersinia and immune responses of the host

Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...

Im Focus: Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.

While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...

Im Focus: Studying fundamental particles in materials

Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales

Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...

Im Focus: Designing Architecture with Solar Building Envelopes

Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.

As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Sustainable Water use in Agriculture in Eastern Europe and Central Asia

19.01.2017 | Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

 
Latest News

New Study Will Help Find the Best Locations for Thermal Power Stations in Iceland

19.01.2017 | Earth Sciences

Not of Divided Mind

19.01.2017 | Life Sciences

Molecule flash mob

19.01.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>