Mushroom Extract May Slow Some Prostate Cancer

The bad news is that the good news only applies to men whose prostate cancer has already spread to other parts of their bodies, and whose testosterone levels have been lowered by drug therapy. The good news is that for those men, a natural product called genistein-combined polysaccharide, or GCP, which is commercially available in health stores, could help keep them alive. A news release from the University of California at Davis reports that researchers at the school found that the combination of the compounds genistein and daidzein, both present in GCP, helps block a key mechanism used by prostate cancer cells to survive in the face of testosterone deprivation. GCP is a proprietary extract cultured from soybeans and shiitake mushrooms and marketed by Amino-Up of Sapporo, Japan. The researchers had earlier shown that when a patient’s androgen level goes down, cancerous prostate cells kick out a protein known as filamin A. They also knew that once filamin A leaves the cancerous cell’s nucleus, that cell no longer requires androgens to survive. Thus, loss of filamin A allows these cells to survive androgen deprivation, and the cancer essentially becomes incurable. The researchers found that GCP keeps filamin A in the nucleus, starving cancerous cells of androgens, and, theoretically at least, prolonging the patient’s life. The researchers hope to begin clinical trials soon.