The periurethral zone of the prostate of the cynomolgus monkey is the most sensitive prostate part for an estrogenic stimulus

Abstract

In man, benign prostatic hyperplasia (BPH) develops in the so-called transition zone of the periurethral region of the prostate. Assuming that estrogens have a specific effect in this context, it would be expected that the periurethral glands are the most sensitive prostate part for an estrogenic stimulus. Morphological and immunocytochemical studies of serial sections of the prostate of castrated male adult cynomolgus monkeys treated with 17 beta-estradiol for a period of three months revealed stromal proliferation, hyperplasia, and hypertrophy of the keratin-positive basal cells and squamous epithelial metaplasia. These estrogen-induced effects were most marked or found exclusively in the dorsal periurethral glands--a finding that is inconsistent with pertinent animal studies conducted thus far on this subject, and which further bears out the suitability of the cynomolgus monkey as a model for investigating BPH.

Genistein chemoprevention of prostate cancer in TRAMP mice

“…This antiprogestational, in addition to its antiestrogenic, activity of ICI may be important in relation to its anti-cancer activity in vivo . In the prostate, AR has been shown to be down-regulated by estrogen during development [29,30]. In our study, AR levels were significantly decreased in the prostate of TRAMPs treated with ICI, suggesting that AR is dependent on ER-α action to be maintained or that ICI has anti-androgen activity.…”

“…Androgen and estrogen play a role in the normal development of the male reproductive tract and are believed to contribute to prostate cancer development [29,30]. Since genistein has been shown to bind to estrogen receptors and to exert estrogen like activity in the female reproductive tract, it has been categorized as a phytoestrogen.…”

Expression of Estrogen Receptor α and β mRNAs in Prostate Cancers Treated with Leuprorelin Acetate

“…Mobbs et al [9], however, reported no effects of androgen deprivation on ER levels either in BPH or carcinoma when the whole tissues were examined. Down–regulation of ER by androgen has been demonstrated clearly in monkeys [17, 18], but in rats there is evidence of an opposite effect since castration decreases ER expression in the prostate [19, 20]. In our standard protocol, all the patients who confirmed to bear prostate cancer are immediately treated with leuprorelin acetate.…”

Male Genital Tract

“…19,20 The canine prostate is not divided into separate lobes but composed predominantly of epithelial components with relatively little fibromuscular stroma. 27 As in the human gland, it has been shown that both the stromal and glandular components respond to hormonal stimulation, especially the caudal or periurethral zone. 21,22 Histologically, fibrous band-like septa can be recognized.…”

“…It is broadly similar to the human gland although there are subtle differences in the vascular supply and musculature around the urinary outflow tract. 27 Paired seminal vesicles of cynomolgus monkeys consist of individual highly convoluted glands containing rounded acini with a simple columnar epithelium. Acid phosphatase is an important hormone-dependent secretion of the canine prostate, although a major secretory component with enzymatic activity in the canine prostate is arginine esterase.…”