Research question: What are the protein levels and localization of oestrogen receptors (including ERa, ERb and G protein-coupled oestrogen receptor [GPER]) and hypoxia-inducible factor-1alpha (HIF-1a) in normal control endometrium (COEM) and ectopic endometrium from abdominal wall endometriosis (AWE).

Design: AWE (n = 20) were obtained during surgery; COEM (n = 40) were collected by curettage. All tissues were obtained during the proliferative or secretory phase. Formalin-fixed paraffin-embedded tissues were used for immunohistochemical study for oestrogen receptors and HIF-1a proteins.

Result(s): The expression of oestrogen receptors and HIF-1a in AWE differed from that in the corresponding menstrual cycle phase of COEM. Compared with COEM, ERa and HIF-1a were decreased whereas ERb and GPER were increased in AWE. The greatest difference was in GPER, with increased protein expression in both the cytoplasm and nucleus of endometrial epithelial and stromal cells, as well as a distinct change in localization from cytoplasmic expression to nuclear and cytoplasmic expression, compared with COEM.

Conclusions: Our data suggest that the expression changes of oestrogen receptors and HIF-1a, especially GPER, are associated with AWE, which may provide new clues to understanding the cause of endometriosis.

研究问题：正常对照子宫内膜（COEM）和异位中雌激素受体（包括ERa，ERb和G蛋白偶联雌激素受体[GPER]）和低氧诱导因子-1α（HIF-1a）的蛋白水平和定位是什么腹壁子宫内膜异位症（AWE）引起的子宫内膜。

设计： 手术期间获得AWE（n = 20）； 通过刮宫收集COEM（n = 40）。所有组织均在增殖或分泌期获得。用福尔马林固定的石蜡包埋的组织用于免疫组化研究雌激素受体和HIF-1a蛋白。

结果： AWE中雌激素受体和HIF-1a的表达与相应的COEM月经周期不同。与COEM相比，AWE中ERa和HIF-1a降低，而ERb和GPER升高。与COEM相比，GPER的最大差异在于子宫内膜上皮和基质细胞的细胞质和细胞核中的蛋白质表达均增加，并且从细胞质表达到核和细胞质表达的定位发生了明显变化。

结论：我们的数据表明雌激素受体和HIF-1a，特别是GPER的表达变化与AWE有关，这可能为了解子宫内膜异位症的病因提供新的线索。