子宫内膜异位症（EMs）是一种常见的雌激素依赖性疾病，而17β-羟类固醇脱氢酶2（17β-HSD2）在调控雌激素活性中起重要作用。但是，对于17β-HSD2缺乏导致的雌激素水平上升是如何诱发子宫内膜异位症的机制目前仍知之甚少。由于雌激素能够诱导干细胞的增殖和分化，近期研究结果又提示子宫内膜异位症可能是一种干细胞相关性疾病。因此，我们提出17β-HSD2缺乏导致干细胞异常增殖可能是子宫内膜异位症发病的重要机制之一。本研究以17β-HSD2为切入点，通过流式分选出富集子宫内膜干细胞的细胞群，原代培养克隆形成纯化子宫内膜干细胞，体内子宫内膜再生实验验证干细胞再生能力，深入研究17β-HSD2与子宫内膜干细胞异位增殖的关系，以及这一过程中17β-HSD2及其调控因子与子宫内膜异位症发生和发展的关系。试图从干细胞增殖的角度揭示内异症的发病机制，为内异症的治疗提供新策略和新途径。

Endometriosis (EMs) is an estrogen dependent disease, and 17β-hydroxysteroid dehydrogenase-2(17β-HSD2 )plays an important role in the regulation of estrogen activity. However, it is still poorly understood how increased estrogen by lack of 17β-HSD2 triggers endometriosis. Since estrogen can induce the proliferation and differentiation of stem cells, recent studies suggest that endometriosis may be a stem cell related disease. Therefore, we proposed that abnormal proliferation of stem cells due to lack of 17β-HSD2 might be one of the important mechanisms of endometriosis. We plan to use fluorescence-activated cell sorting to purify stem cell enriched fraction, and then get more and purified stem cells through clone formation experiment. In vivo transplantation experiment will be used to confirm the regeneration ability of the purified stem cells. This study aims to detect the role of 17β-HSD2 played in the ectopic growth of endometrial stem cells and how this process contributes to the formation and development of endometriosis. We attend to investigate the function of endometrial stem cells in pathogenesis of endometriosis, providing new strategies for the treatment of this disease.