Androgens and prostate cancer

Prostate cancer is the most common nonskin cancer among American men and the third leading cause of cancer deaths. Research data over many years of study support the role of androgen in driving prostate cancer growth, proliferation, and progression. Androgens are steroid hormones that induce the differentiation and maturation of the male reproductive organs. Testosterone is the principal androgen in circulation, while dihydrotestosterone (DHT) is the primary nuclear androgen, and the action of DHT in the prostate is mediated by the androgen receptor. Within the prostate, DHT binds to the androgen receptor to form an intracellular complex that binds to androgen-response elements in the DNA of prostate cells inducing proliferation. Testosterone deficiency is common among aging American males, and a number of men suffering from testosterone deficiency may be relieved of their symptoms, receiving a boost in their quality of life, but are often denied treatment due to the fear that the addition of higher testosterone from replacement therapy may cause growth of occult prostate cancer. Several small studies show that, with the right patient population, testosterone replacement after curative therapy is safe. However, a large placebo-controlled prospective trial to provide the definitive study is needed.