Androgen, estrogen, and progesterone receptors in normal and aging prostates

Testicular hormones regulate the growth and development of the prostate. The presence of androgen receptors in prostatic tissue and their importance in the normal development of the prostate has been established. Age-related changes in the hormonal milieu, and perhaps steroid hormone receptor profile, could set in motion pathological changes leading to the onset of benign prostatic hyperplasia (BPH) or prostate cancer which primarily affect older men. The accumulation of dihydrotestosterone with age, the reawakening of the inductive potential of the prostatic stroma, the altered rate of apoptosis with age, and the age-related changes in the ratio of testosterone:estrogen have all been implicated in the etiology of BPH. In addition to androgen receptors, several studies have documented the presence of estrogen and progesterone receptors in BPH and prostate cancer. So far, most studies have focussed on the correlation between the presence/absence of steroid hormone receptors and response to hormonal therapy. The molecular mechanisms by which these steroid hormone receptors regulate the onset or progression of BPH and prostate cancer are not yet clear. The chronological changes in the levels and distribution of steroid hormone receptors in normal prostatic tissue and the effect of such changes on the synthesis of growth factors, growth factor receptors, and oncogenes should be investigated.