Steroid Hormone Receptors in the Prostate

Abstract

Specific receptors for dihydrotestosterone and estradiol-17-beta have been identified in cytosols of the human and baboon prostate. Binding of radioactive estradiol-17-beta to the 0.4 M potassium chloride extractable component of human prostate nuclei also was demonstrated. Cyproterone acetate and diethylstilbestrol, agents of known high affinity for dihydrotestosterone and estradiol-17-beta receptors, respectively, did not bind significantly to sex hormone binding globulin and, therefore, were useful as competitors in distinguishing binding of dihydrotestosterone and estradiol-17-beta to sex hormone binding globulin and to their specific receptors. Displacement of [3H]-estradiol-17-beta binding by diethylstilbestrol in cytosols of 11 needle biopsy specimens (mean equals 16.8 mg.) from prostatic cancer patients was analyzed. These preliminary data indicated a trend towards greater competition by diethylstilbestrol for high affinity binding sites in differentiated tumor specimens from men who were not receiving estrogen therapy. Objective and subjective responses to hormone therapy were recorded in these patients, whereas the disease in those men with low displacement assay values progressed.

Characterization and measurement of cytoplasmic and nuclear oestradiol-17β-receptor proteins in benign hypertrophied human prostate

“…Additionally, the abilities of unlabelled oestradiol and DES but not progesterone or DHT to compete for the binding of [3H]oestradiol provide support for the specific nature of this binding component. An essentially similar pattern of steroid specificity has been reported for the cytoplasmic oestradiol receptors in the prostate of other species, (Chaisiri et al 1978;Karr et al 1979;Markland & Lee, 1979) as well as in classical oestrogen target organs (King & Mainwaring, 1974). Our data on steroid specificity are consistent with those reported by Pertshuk, Zava, Tobin, Brigati, Gaetjens, Macchia, Wise, Wax & Kim (1979) who employed a histofluorometric technique for the identification of an oestrogen-binding protein in the cytoplasmic and nuclear compartments of human BPH tissues.…”

“…Using tissue from patients with benign hyperplasia of the prostate, evidence for the presence of oestradiol and its close relationship to dihydrotestosterone and 5cc-androstane3a,17ß-diol has recently been presented by Ghanadian & Puah (1981). In addition to the existence of oestradiol in the prostate, the presence of cytoplasmic oestrogen receptors has been reported in the prostate of the rat (Armstrong & Bashirelahi, 1978), dog (Chaisiri, Volotaire, Brownen, Evans & Pierrepoint, 1978), baboon (Karr, Sufrin, Kirdani, Murphy & Sandberg, 1978) and normal man (Karr, Wajsman, Madajewicz, Kirdani, Murphy & Sandberg, 1979). However, data with regard to the presence of this receptor in the benign hypertrophied human prostate (BPH) has been controversial.…”

Effects of Mepartricin, a polyene macrolide agent, on fecal excretion and serum concentration of estrogen and number of prostatic estrogen receptors in immature rats

“…In recent years, increasing attention has been given to the roles of estrogens as factors which function in concert with androgens and lead to prostate hypertrophy. The findings of epidemiological studies [9][10][11][12][13], studies employing culture systems for human hyperplastic prostate tissue [14,15], studies employing a prostatic hyperplasia model created by hormone induction in castrated dogs [16,17], and other research indicate that estrogens, in addition to androgens, play important roles in the development of prostatic hyperplasia.…”

“…However, in recent years several lines of evidence support a role of estrogen in the pathogenesis and maintenance of BPH, i.e., in humans, a shift in the estrogen/androgen balance in favor of estrogens is arising with age [7][8][9], and it has been shown that the estrogen concentration in the blood and BPH tissue [10,11], and the amount of excretion of estrogen in urine, are high in BPH patients [12]. Moreover, it has been demonstrated that estrogen receptors (ER) exist in the stroma of the human prostate gland [13], and that estrogen enhances the androgen responsiveness of stroma cells derived from the human hyperplastic prostate [14]. These and other research findings thus provide strong evidence of the involvement of estrogen in BPH.…”

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

“…Thus some researchers found benign prostatic hyperplasia (BPH) to be ER positive while others reported negative data [1, 2, 3, 4]. Recent investigations using monoclonal antibodies against ER–α mostly point to a presence of the receptor in prostate tissue, possibly with the dominant presence in stromal cells [5, 6, 7].…”