No 13/August 2, 2005
Double Pack - Cancer Researchers in Berlin Confirm Existence of a Second Protection System for Cells It Blocks Lymphoma Development
E m b a r g o e d until: Wednesday, August 3, 2005, 18 hours London Time/13 00 US Eastern Time
Cells under stress apparently possess two different safety systems that prevent them from turning into cancer cells. Apoptosis is one such system, which enables damaged cells to literally commit suicide in order to protect the organism as a whole. The second protection program stops the cell cycle, and – although the cells stay alive – they are prevented from further dividing a behavior that would lead to malignant growth. Evidence suggesting the existence of this second system was found a few years ago in the culture dish. Now, using animal models, cancer researchers from the Charité University Medicine Berlin and the Max Delbrück Center for Molecular Medicine (MDC) Berlin-Buch in Germany have been able to confirm this second program termed senescene (Latin: senex = “old age”) and they could show that this program is capable of blocking lymphoma development. The work of Melanie Braig under the guidance of Charité- and MDC-based principal investigator Prof. Clemens A. Schmitt has now been published online in Nature* (doi:10.1038/nature03841).
An enzyme, which the researchers refer to as Suv39h1, plays an important role in mediating senescence in white blood cells (lymphocytes). The enzyme is activated when the oncogene ras turns on genes in lymphocytes, and prevents them from undergoing uncontrolled cell growth and, subsequent conversion into cancer cells. Hence, lack of Suv39h1 can pave the way for the development of a very aggressive lymphoma. Interestingly, the availability of the apoptotic program is not disengaged by cellular senescence. Thus the tumor can still be treated with chemotherapy that engages apoptotic programs to kill cancerous cells.
*Oncogene-induced senescence as an initial barrier in lymphoma development
Melanie Braig1, Soyoung Lee1, Christoph Loddenkemper2, Cornelia Rudolph3, Antoine H.F.M. Peters4,5, Brigitte Schlegelberger3, Harald Stein2, Bernd Dörken1,6, Thomas Jenuwein5 & Clemens A. Schmitt1,6
1Charité -
Universitätsmedizin Berlin/Haematology-Oncology, 13353
Prof. Dr. med. Clemens Schmitt, M.D.
Charité - Universitätsmedizin Berlin (CVK), and MDC
Augustenburger Platz 1
13353 Berlin, Germany
Tel. +49-30-450 553 687
Fax +49-30-450 553 986
Mobile +49-163-76 96 864
e-mail clemens.schmitt@charite.de
Barbara Bachtler
Press and Public Affairs
Max Delbrück Center for Molecular Medicine (MDC) Berlin-Buch
Robert-Rössle-Straße 10
13125 Berlin
Germany
Phone.: +49 (0) 30 94 06 - 38 96
Fax: +49 (0) 30 94 06 - 38 33
e-mail: presse@mdc-berlin.de