E-钙黏蛋白基因启动子区甲基化在卵巢子宫内膜异位症中作用的研究

Investigation of the Role of CDH1 Promoter Methylation in Ovarian Endometriosis

目的探讨E-钙黏蛋白基因(CDH1)启动子区甲基化状态及其在卵巢子宫内膜异位症中的作用。方法选择2011年10月—2013年8月河北医科大学第四医院诊治的50例经手术确诊的卵巢子宫内膜异位症患者和50例由于宫颈上皮内瘤变(CIN)Ⅲ级行子宫切除或子宫探查的对照妇女为研究对象,采用甲基化特异性聚合酶链式反应检测卵巢子宫内膜异位症患者在位内膜(在位内膜组)、异位内膜(异位内膜组)和对照妇女子宫内膜组织(对照子宫内膜组)CDH1启动子区甲基化状态;采用反转录聚合酶链式反应(RT-PCR)和流式细胞术检测CDH1启动子区甲基化阳性组织(甲基化阳性组)和甲基化阴性组织(甲基化阴性组)CDH1 mRNA、E-钙黏蛋白(E-cadherin)表达水平。结果在位内膜组CDH1启动子区甲基化阳性率为26.0%(13/50)、异位内膜组CDH1启动子区甲基化阳性率为32.0%(16/50)、对照子宫内膜组为8.0%(4/50),在位内膜组和异位内膜组CDH1启动子区甲基化阳性率明显高于对照子宫内膜组(P=0.017、0.003)。甲基化阳性组CDH1 mRNA、E-cadherin表达水平[(0.4±0.2)、(129.0±17.5)]明显低于甲基化阴性组[(0.6±0.1)、(158.0±51.0)](P=0.023、0.035)。结论卵巢子宫内膜异位症患者的在位、异位内膜组织存在着CDH1启动子区异常甲基化,甲基化阳性、阴性组织中CDH1 mRNA和E-cadherin表达水平有明显差异。提示CDH1启动子区的异常甲基化可能与卵巢子宫内膜异位症的发生相关。

Objective To investigate the methylation status of the promoter region of the E-cadherin gene(CDH1)and its role in ovarian endometriosis.Methods We selected 50 patients with ovarian endometriosis who were diagnosed surgically and treated in Fourth Hospital of Hebei Medical University between October 2011 and August 2013,and 50 control cases who underwent hysterectomy or uterine exploration due to gradeⅢcervical intraepithelial neoplasia during the same period.The methylation status of the CDH1 promoter in eutopic endometrium tissues(eutopic endometrium group)and ectopic endometrium tissues(ectopic endometrium group)in the patients with ovarian endometriosis and in the control subjects(control endometrium group)was detected through methylation-specific PCR(MSP).RT-PCR and flow cytometry were used to detect the expression levels of CDH1 mRNA and E-cadherin in CDH1 promoter methylation positive tissues and CDH1 promoter methylation negative tissues.Results The positive methylation rate of the CDH1 promoter was 26.0%(13/50)in the eutopic endometrium group,and 32.0%(16/50)and 8.0%(4/50)in the ectopic endometrium group and control endometrium group,respectively;the positive methylation rates in the eutopic endometrium group and ectopic endometrium group were significantly higher than those in the control endometrium group(P=0.017,0.003).The levels of CDH1 mRNA and E-cadherin protein in methylation-positive samples〔(0.4±0.2),(129.0±17.5)〕were significantly lower than those in the methylationnegative samples〔(0.6±0.1),(158.0±51.0)〕(P=0.023,0.035).Conclusion The CDH1 promoter region in eutopic and ectopic endometrium tissues is abnormally methylated,and the expression levels of CDH1 mRNA and E-cadherin in methylation positive and negative tissues were significantly different,thus suggesting that abnormal methylation of the CDH1 promoter may be involved in the development of ovarian endometriosis.