Falany J L, Azziz R, Falany C N
Department of Pharmacology and Toxicology, University of Alabama, Birmingham 35294, USA.
Chem Biol Interact. 1998 Feb 20;109(1-3):329-39. doi: 10.1016/s0009-2797(97)00143-9.
Understanding the factors which alter estrogen metabolism and activity in endometrial tissue is important because unopposed estrogen stimulation is an important risk factor in the development of endometrial carcinoma. The cyclic progression of the endometrium through proliferative and secretory phases is normally under the control of the ovarian hormones beta-estradiol (E2) and progesterone. One mechanism by which progesterone inhibits the activity of E2 in secretory endometrium is by elevating the degree of E2 sulfation, thereby reducing its ability to bind to the estrogen receptor and elicit a cellular response. Our laboratories have investigated the cytosolic sulfotransferases (STs) found in biopsies of both proliferative and secretory endometrium obtained from five normal pre-menopausal women who were not taking any drugs or steroids. Two of the human cytosolic STs were detected in human endometrial tissues. The phenol-sulfating form of phenol ST (P-PST) was found at varying levels in cytosol from both proliferative and secretory endometrium in all of the women studied but with no consistent correlation to the phase of the menstrual cycle. In contrast, estrogen ST (EST) was not detected in the proliferative endometrial cytosol of any of the women studied but was consistently found in all of the secretory endometrial cytosols. The presence and levels of these STs was confirmed by ST activity studies, immunoblot analysis and Northern blot analysis. These results indicate that the expression of EST in human endometrial tissues varies with the phase of the menstrual cycle and is most likely regulated by progesterone secreted from the ovaries.
了解改变子宫内膜组织中雌激素代谢和活性的因素非常重要，因为无对抗的雌激素刺激是子宫内膜癌发生的一个重要风险因素。子宫内膜通过增殖期和分泌期的周期性进展通常受卵巢激素β-雌二醇（E2）和孕酮的控制。孕酮在分泌期子宫内膜中抑制E2活性的一种机制是提高E2硫酸化程度，从而降低其与雌激素受体结合并引发细胞反应的能力。我们实验室研究了从五名未服用任何药物或类固醇的正常绝经前女性获取的增殖期和分泌期子宫内膜活检组织中发现的胞质硫酸转移酶（STs）。在人类子宫内膜组织中检测到了两种人类胞质STs。在所研究的所有女性中，增殖期和分泌期子宫内膜胞质中均发现了不同水平的酚硫酸转移酶（P-PST）的酚硫酸化形式，但与月经周期阶段无一致相关性。相比之下，在所研究的任何女性的增殖期子宫内膜胞质中均未检测到雌激素硫酸转移酶（EST），但在所有分泌期子宫内膜胞质中均持续检测到。通过ST活性研究、免疫印迹分析和Northern印迹分析证实了这些STs的存在和水平。这些结果表明，人类子宫内膜组织中EST的表达随月经周期阶段而变化，很可能受卵巢分泌的孕酮调节。
