The influence of oestradiol on the metabolism of androgens by human prostatic tissue.

The uptake and metabolism of testosterone, androstenedione and 5alpha-dihydrotestosterone (DHT) by human benign hyperplastic prostates and prostatic carcinomas have been measured in organ culture. DHT was a major metabolite of both testosterone and androstenedione in the benign tissue and the androstanediols were the principal metabolites of DHT. Over half the carcinomas produced less DHT from testosterone than the benign hyperplastic prostates, and carcinomas from the oldest patients showed an enhancement of 17beta-hydroxysteroid dehydrogenation. There was no relationship between these differences in metabolism and the degree of differentiation of the carcinomas. Oestradiol decreased the production of DHT from both testosterone and androstenedione and, at low androgen concentrations, increased the production of androstanediols from testosterone, androstenedione and DHT. Uptake of DHT, but not of the other two androgens, was stimulated by oestradiol.