title: Tamoxifen decreases progesterone and nuclear androgen receptors in the human prostate.
abstract: Androgen (AR) and progesterone (PR) receptors were measured in resected prostate tissues of patients with benign prostatic hypertrophy. One group of patients received an anti-estrogen, tamoxifen (Tm 20 mg b.i.d.) for 10 days prior to prostate resection; a second group served as controls and were untreated. Plasma levels of Tm were 200-500 pmol/ml at the time of surgery. Statistically significant decreases (P less than 0.05) were found in cytosol PR (154 fmol/mg DNA +/- 33 SE in 14 Tm-patients vs 266 +/- 40 SE in 13 untreated patients) and in nuclear AR (103 fmol/mg DNA +/- 70 SE in 18 Tm-patients vs 257 +/- 62 SE in 17 controls). Cytosol AR was not significantly different in Tm-treated patients (257 fmol/mg DNA +/- 79 SE in 15 Tm-patients vs 346 +/- 130 SE in 17 controls, P greater than 0.6). Although receptor recycling is one of several possible explanations, these decreases in progesterone and nuclear androgen receptors in Tm-treated patients suggest that estrogen has a role in the biological regulation of steroid receptors in the human prostate.
mesh_terms: D002467:Cell Nucleus / Q000187:drug effects / Q000378:metabolism; D003600:Cytosol / Q000187:drug effects / Q000378:metabolism; D004247:DNA / Q000378:metabolism; D006801:Humans; D066298:In Vitro Techniques; D008297:Male; D011467:Prostate / Q000187:drug effects / Q000378:metabolism*; D011470:Prostatic Hyperplasia / Q000188:drug therapy* / Q000378:metabolism; D011944:Receptors, Androgen / Q000187:drug effects* / Q000378:metabolism; D011980:Receptors, Progesterone / Q000187:drug effects* / Q000378:metabolism; D011987:Receptors, Steroid / Q000187:drug effects*; D013629:Tamoxifen / Q000494:pharmacology* / Q000627:therapeutic use
chemical_list: D011944:Receptors, Androgen; D011980:Receptors, Progesterone; D011987:Receptors, Steroid; D013629:Tamoxifen; D004247:DNA