Positive Health Online

Abstract

THELEN and colleagues, Department of Urology, Institute of Human Genetics, Georg-August-University, Goettingen, Germany, have studied the inhibition of both telomerase activity and secretion of prostate specific antigen by silibinin (the pure form of the flavonoid antioxidant silymarin in prostate cancer cells.

Background

It has been shown that in the prostate cancer cell line, LNCaP, a crucial factor in carcinogenesis is the telomerase activity induced by the sex hormone, dihydrotestosterone. In this study, the potential of the anti-cancer drug silibinin to downregulate the telomerase activity was investigated.

Methodology

In vitro study using cells in culture and standard molecular biological techniques.

Results

Carcinogenesis, as measured by secretion of a prostate specific antigen, was downregulated by silibinin both in the presence and absence of the carcinogenesis trigger, dihydrotestosterone. Dihydrotestosterone alone stimulated the secretion of the antigen. The expression of the gene encoding telomerase was decreased by silibinin, and the activity of the enzyme was inhibited by silibinin with or without dihydrotestosterone, and stimulated by dihydrotestosterone alone.

Conclusion

The results underline the potential therapeutic use of silibinin as a treatment for prostate cancer.

References

Thelen P, Wuttke W, Jarry H, Grzmil M, Ringert RH. Inhibition of telomerase activity and secretion of prostate specific antigen by silibinin in prostate cancer cells. The Journal of Urology 171 (5): 1934-1938, May 2004.