Which play a more important role in the development of large-sized prostates (aparts per thousandyen80 ml), androgen receptors or oestrogen receptors? A comparative study

To compare the expression levels of androgen receptor (AR), oestrogen receptor alpha (ER alpha)and oestrogen receptor beta (ER beta) in human prostate with various degrees of benign hyperplasia. Forty-five BPH patients undergoing transurethral plasmakinetic resection of the prostate were divided into three 15-people groups of participants with small (< 40 ml), medium (40-80 ml) and large (> 80 ml) prostates. Patient blood samples were collected for measuring serum oestradiol (E2), total testosterone (TT), follicle-stimulating and luteinizing hormone by radioimmunoassay. Postoperative prostate specimens were collected to detect AR, ER alpha and ER beta expression by immunoblotting and immunohistochemical staining. There were significantly lower serum E2 levels in the patients with large prostates compared to the patients with small prostates (P < 0.05) and medium prostates (P < 0.01). A high TT and E2 serum ratio was observed in patients with large-sized prostates (P < 0.05), but there were no obvious differences in the serum TT levels between the three groups. Prostate AR expression in patients with large- (P < 0.05) and medium-sized prostates (P < 0.01) was high compared to patients with small-sized prostates. Prostate ER alpha expression in patients with large prostates was low compared to patients with small- and medium-sized prostates (P < 0.01). The prostate ER beta expression did not differ between the three groups (P > 0.05). Increased AR and decreased ER alpha expression in the prostate suggested that AR might be more important than ER alpha in stimulating prostate proliferation in patients with large-sized prostates. Patients with small- and large-sized prostates might require different management procedures involving selective oestrogen receptor modulators and selective androgen receptor modulators, respectively.