Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Mutation Makes Cells Sloppy

12.05.2009
Whether blood, colon or breast cancer: In approximately 80 percent of all tumour diseases, the p53 gene has mutated in human cancer cells. Scientists of the University of Würzburg Biocenter depict the consequences of this in the Cancer Research journal.

New blood cells develop, cells of the intestinal mucosa renew themselves, dead skin cells are replaced - cells continually divide in the human body. If any errors occur in this process, danger is imminent: Diseases can develop, for instance cancer, and that is why the organism controls this complicated process very carefully.

The p53 contains the blueprint for a protein that is essential for a controlled cell division. In general, it is proteins that spur and control a cell division. Their production in the cell, therefore, follows a precise time schedule.

So the genes that provide the parameters for building the proteins must be activated and deactivated again at very specific points in time. "Above all, it must be ensured that these genes are deactivated after the cell division; otherwise, the cell will continue to grow in an uncontrolled manner", says Professor Stefan Gaubatz.

DNA damages bring the p53 protein on the scene

In every cell division, there are certain control points at which the cell checks the proper sequence of the division, detects any damage done and repairs it. If the DNA has been damaged, the p53 protein comes on the scene: It ensures that from a major protein complex called LINC, a part that carries the designation B-MYB detaches. The remaining part of the complex then silences genes that promote the cell growth. The cell in turn slows down its growth and thus gains enough time to repair the damages. It is this mechanism that has been elucidated by the study group of Stefan Gaubatz.

Without p53, defects accumulate

In many cancer cells, the p53 has mutated and thus lost its function. "The tumour cells can no longer completely stop the cell cycle then", the Würzburg researcher explains. This makes them sloppy and hasty: Defects in the DNA are not repaired, but the cell division proceeds. Damages accumulate and may make the tumour more and more difficult to treat. It is also conceivable that this mechanism triggers carcinogenesis in the first place.

What exactly happens in cancer cells with mutated p53? The Gaubatz team has found out with the help of cell cultures: Even if the DNA gets damaged in the cell division process, the composition of the major LINC protein complex remains unchanged - the B-MYB protein part no longer detaches. Then the researchers, by way of experiment, made sure that this step did take place nevertheless. The result: The cancer cells were able to stop the cell division process again.

Next steps in research

The next steps now consist in verifying this effect in animal models. In addition, the scientists want to investigate more closely how B-MYB and the protein complex are regulated. From their research work, they ultimately expect new approaches for improved cancer treatment.

The Munich-based Wilhelm-Sander foundation supports the project, and so does the Deutsche Forschungsgemeinschaft within the scope of the Transregio SFB TR17 (Ras-dependent pathways in human cancer).

For further information

Prof. Dr. Stefan Gaubatz, Lehrstuhl für Physiologische Chemie I, University of Würzburg, phone ++49 931 31-84138, stefan.gaubatz@biozentrum.uni-wuerzburg.de

"B-MYB is required for recovery from the DNA damage-induced G2 checkpoint in p53 mutant cells", Mirijam Mannefeld, Elena Klassen, Stefan Gaubatz, Cancer Research, 2009, 69 (9), pp. 4073-4080, doi:10.1158/0008-5472.CAN-08-4156

Robert Emmerich | idw
Further information:
http://www.uni-wuerzburg.de/

More articles from Life Sciences:

nachricht World’s Largest Study on Allergic Rhinitis Reveals new Risk Genes
17.07.2018 | Helmholtz Zentrum München - Deutsches Forschungszentrum für Gesundheit und Umwelt

nachricht Plant mothers talk to their embryos via the hormone auxin
17.07.2018 | Institute of Science and Technology Austria

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: First evidence on the source of extragalactic particles

For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.

To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...

Im Focus: Magnetic vortices: Two independent magnetic skyrmion phases discovered in a single material

For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.

Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...

Im Focus: Breaking the bond: To take part or not?

Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.

A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...

Im Focus: New 2D Spectroscopy Methods

Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.

"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....

Im Focus: Chemical reactions in the light of ultrashort X-ray pulses from free-electron lasers

Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.

Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Leading experts in Diabetes, Metabolism and Biomedical Engineering discuss Precision Medicine

13.07.2018 | Event News

Conference on Laser Polishing – LaP: Fine Tuning for Surfaces

12.07.2018 | Event News

11th European Wood-based Panel Symposium 2018: Meeting point for the wood-based materials industry

03.07.2018 | Event News

 
Latest News

World’s Largest Study on Allergic Rhinitis Reveals new Risk Genes

17.07.2018 | Life Sciences

Electronic stickers to streamline large-scale 'internet of things'

17.07.2018 | Information Technology

Behavior-influencing policies are critical for mass market success of low carbon vehicles

17.07.2018 | Power and Electrical Engineering

VideoLinks
Science & Research
Overview of more VideoLinks >>>