Effect of stilboestrol and testosterone on the incorporation of 75selenomethionine by prostatic carcinoma cells.

Controversy still exists as to whether oestrogens exert a direct effect on the prostatic cell. Incorporation of 75Selenomethionine (SeM) was used as a measure of protein synthesis by prostatic carcinoma cells in vitro to investigate the action of hormones on prostatic carcinoma cells in tissue culture. Stilboestrol (DES) and stilboestrol diphosphate (Honvan) inhibited protein synthesis in a proportion of patients, while testosterone was stimulatory. A similar effect was noted in cells from patients with benign hyperplasia (BPH). This work confirms that oestrogens have a direct inhibitory effect on prostatic cells at high concentrations which can be attained in patients given intravenous stilboestrol diphosphate.