Weng Huinan, Liu Fenghua, Hu Shuiwang, Li Li, Wang Yifeng
Department of Pathophysiology, Key Laboratory of Proteomics of Guangdong Province, Southern Medical University, Guangzhou, China.
GuangDong Women and Children Hospital, Guangzhou, China.
J Transl Med. 2014 Nov 4;12:306. doi: 10.1186/s12967-014-0306-y.
Endometriosis is a benign chronic gynecological disease that affects women of reproductive age, characterized by the presence of functional endometrial tissues outside the uterine cavity. GnRH agonists exhibit anti-proliferative and apoptosis-enhancing activities and have long been used for the treatment of endometriosis. There is a critical need to identify the signaling modules involving GnRH agonist therapy for the treatment of endometriosis. In this study, we compared the proteomic profiles of endometriosis in patients before and after GnRH agonist therapy to identify proteins that might provide further information concerning the mechanisms underlying the functions of GnRH agonists.
A total of 55 protein spots with different abundances were observed using Difference Gel Electrophoresis (DIGE), and 26 of these proteins were assigned clear identities through Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Tandem Mass Spectroscopy (MALDI-TOF/TOF MS).
We validated four of these proteins through Western blotting and immunohistochemistry using human endometrial tissue. We also characterized the effect of Leuprolide acetate (LA) on the apoptosis of eutopic endometrial epithelial cells. LA treatment significantly promoted the apoptosis of eutopic endometrial epithelial cells and inhibited the expression of the anti-apoptotic factor GRP78. GRP78 knockdown enhanced LA-induced cell apoptosis, whereas, the overexpression of GRP78 in eutopic endometrial epithelial cells suppresses LA-induced apoptosis.
These results suggest that GnRH agonists induce endometrial epithelial cell apoptosis via GRP78 down-regulation. This study might provide an important molecular framework for further evaluation of GnRH agonist therapy.
子宫内膜异位症是一种影响育龄女性的良性慢性妇科疾病，其特征是子宫腔外存在功能性子宫内膜组织。促性腺激素释放激素（GnRH）激动剂具有抗增殖和增强凋亡的活性，长期以来一直用于治疗子宫内膜异位症。迫切需要确定涉及GnRH激动剂治疗子宫内膜异位症的信号模块。在本研究中，我们比较了GnRH激动剂治疗前后子宫内膜异位症患者的蛋白质组学图谱，以鉴定可能提供有关GnRH激动剂功能机制进一步信息的蛋白质。
使用差异凝胶电泳（DIGE）观察到总共55个丰度不同的蛋白质斑点，其中26种蛋白质通过基质辅助激光解吸/电离飞行时间串联质谱（MALDI-TOF/TOF MS）确定了明确的身份。
我们通过使用人子宫内膜组织的蛋白质免疫印迹和免疫组织化学验证了其中四种蛋白质。我们还表征了醋酸亮丙瑞林（LA）对在位子宫内膜上皮细胞凋亡的影响。LA处理显著促进在位子宫内膜上皮细胞的凋亡，并抑制抗凋亡因子GRP78的表达。GRP78基因敲低增强了LA诱导的细胞凋亡，而在位子宫内膜上皮细胞中GRP78的过表达抑制了LA诱导的凋亡。
这些结果表明，GnRH激动剂通过下调GRP78诱导子宫内膜上皮细胞凋亡。本研究可能为进一步评估GnRH激动剂治疗提供重要的分子框架。
