Testosterone inhibits estrogen‐induced mammary epithelial proliferation and suppresses estrogen receptor expression

@article{Zhou2000TestosteroneIE,
  title={Testosterone inhibits estrogen‐induced mammary epithelial proliferation and suppresses estrogen receptor expression},
  author={J Zhou and S Ng and O Adesanya-Famuiya and K. Anderson and Carolyn A. Bondy},
  journal={The FASEB Journal},
  year={2000},
  volume={14},
  pages={1725 - 1730}
}
This study investigated the effect of sex steroids and tamoxifen on primate mammary epithelial proliferation and steroid receptor gene expression. Ovariectomized rhesus monkeys were treated with placebo, 17β estradiol (E2) alone or in combination with progesterone (E2/P) or testosterone (E2/T), or tamoxifen for 3 days. E2 alone increased mammary epithelial proliferation by ~sixfold (P<0.0001) and increased mammary epithelial estrogen receptor (ERα) mRNA expression by ~50% (P<0.0001; ERβ mRNA… Expand
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TLDR
T and DHT inhibited proliferation and increased apoptosis in the epithelium of cultured normal HBT and opposed E(2)-stimulated proliferation and cell survival in an AR-dependent manner and were associated with changes in the proportions of ERα- and AR-positive epithelial cells. Expand
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Immunocytochemical Localization of Sex Steroid Hormone Receptors in Normal Human Mammary Gland
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  • Chemistry, Medicine
  • The journal of histochemistry and cytochemistry : official journal of the Histochemistry Society
  • 2010
TLDR
All sex steroids can directly act on epithelial cells to modulate development and function of the human mammary gland, and estrogens and androgens can also indirectly influence epithelial cell activity by an action on stromal cells. Expand
AIB1 sequestration by androgen receptor inhibits estrogen-dependent cyclin D1 expression in breast cancer cells
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The hypothesis that AIB1 sequestration by AR may be an effective mechanism to explain the reduction of estrogen-induced cyclin D1 gene activity in estrogen-dependent breast cancer cells is supported. Expand
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