Prostate cancer: Improving the success of treatment
Prostate cancer is the most frequent malignant tumour in men. Major treatment options involve surgery, radiation and hormone therapy. However, some prostate tumours do not respond to such treatment. As part of the national “Cell adhesion, invasion and metastasation” research alliance, researchers from Freiburg and Bonn have succeeded in developing the basics for new therapies, in particular for the treatment of advanced prostate cancer.
Male sex hormones play an important part in the development of prostate cancer. These androgens promote the development of secondary male sex characteristics. The most important androgen is the hormone testosterone. The nuclei of prostate cancer cells have hormone receptors which the androgens find. This triggers the proliferation of cancer cells.
The proliferation of cancer cells can be inhibited with antihormones, which block the receptors and prevent the androgens from binding. However, the growth of some prostate tumours cannot be impeded. Previously, very little was understood about the molecular mechanisms.
Researchers from Freiburg and Bonn have now succeeded in clarifying this phenomenon. The tumour cells activate stimulating enzymes, also known as cofactors or coactivators. This leads to a considerable increase in the activities of the androgen receptor. At the same time, certain genes that regulate cancer growth are altered. This enables tumour cells to survive and grow despite treatment with antiandrogenic drugs. This means that the cancer cells become resistant to cancer therapy.
One of the approaches taken by the scientists is to chemically inhibit the co-activators. The scientists have already succeeded in halting the growth of resistant prostate cancer cells in the laboratory. The researchers are now hoping to systematically develop these chemical inhibitors further in order to produce new drugs to fight advanced prostate tumours.
The work of the two researcher groups led by Professor Dr. Roland Schüle from the Centre of Clinical Research at Freiburg University, and Professor Dr. Reinhard Büttner from the Institute of Pathology at the University of Bonn, affirms the successful establishment of translational German Cancer Aid–funded cancer research in Top Oncology Centres in Freiburg and Cologne/Bonn. “The combination of basic research with histopathological and clinical data enables us to optimise existing cancer therapies and enhance the development and clinical testing of new drugs,” said Gerd Nettekoven, Managing Director of the German Cancer Aid association.
Every year in Germany, 48,650 men are diagnosed with prostate carcinoma and approximately 11,000 die from this disease. Prostate carcinoma occurs in slow growing and aggressive, rapidly metastasing forms. If the tumour only affects the prostate, the tumour can be radiated. Metastasing tumours are treated with drugs that block the effect of the male sex hormones and hence the growth of the altered cells. The German Cancer Aid’s “Blaue Ratgeber” series (vol. 17) explains the diagnosis, therapy and aftercare of prostate cancer in an easy to understand way.
The results were published as the lead article in the 7th January issue of the renowned journal “Natural Cell Biology”.
Deutsche Krebshilfe (German Cancer Aid)
P.O. Box 1467