The role of soy phytoestrogens in prostate cancer

Epidemiological data of phytoestrogens and prostate cancer strongly supports the cancer protective effects of isoflavones found in soy products. Inhibition of cell proliferation via hormone-dependent and hormone-independent mechanisms by soy phytochemicals has been studied extensively in cell culture and animal studies. Herein, we review the current literature on the epidemiology and effects of two soy phytoestrogens, genistein and daidzein, and would stress the need for controlled human trials to assess the true preventive and therapeutic effects of these compounds.