Androphilic proteins in the human prostate

Abstract

Dihydrotestosterone‐binding protein in cytosols from human prostates was different from the R1881‐and R5020‐binding proteins. The R1881‐and R5020‐binding proteins in the cytosol were very similar and most of the binding sites for R1881 were capable of binding R5020. However, nuclear extracts showed equal binding to dihydrotestosterone and R1881, but not to R5020, suggesting that there might not be a progestin receptor in the human prostate. Maximum binding sites to dihydrotestosterone, R1881, and R5020 in cytosols were very similar among “normal” and pathological prostates except that dihy‐drotestosterone binding was higher in “normal” prostates than in the pathological ones. Histochemically, R1881‐binding was observed in the epithelial cells and in malignant cells, but not in the stroma.

Nuclear androgen receptors in the epithelium and stroma of human benign prostatic hypertrophic glands

“…Trachtenberg et a1 [26], however, have reported RBAs in human prostatic nuclear extracts in the same way as in the present study, and obtained figures of 73% for R 1881, 19% for testosterone, and 0% for 3a-androstanediol and progesterone. Shimazaki et al [27] have reported the binding affinities of five compounds relative to R 1881 in BPH nuclear extract, obtaining results similar to those presented here. In human prostate cytosol, specificity data of androgen receptors for various substances in comparison with R 1881 also appear to be similar to those in the present work [28, 291. The specificity of the binding of various steroids to SHBG, in comparison with testosterone, has recently been summarized in a review article [30].…”