DNA甲基化转移酶DNMTs和甲基化结合蛋白MBDs在卵巢子宫内膜异位症中的表达及相关性研究

Expression and Correlation Analysis of DNA Methyltransferases and Methyl-CpG-Binding Domains in the Ovarian Endometriosis

目的探讨DNA甲基化转移酶(DNA methyltransferases,DNMTs)和甲基化结合蛋白(methyl-CpG-binding domains,MBDs)在卵巢子宫内膜异位症患者子宫内膜及异位内膜中的mRNA表达水平及其相关性。方法收集20例卵巢子宫内膜异位症患者的在位内膜、异位内膜及20例因宫颈上皮内瘤变Ⅲ级手术切除子宫的正常子宫内膜,采用qRT-PCR技术检测其中DNMTs和MBDs的mRNA表达水平,并采用Pearson相关分析探讨DNMTs及MBDs mRNA表达水平的相关性。结果①在位内膜和异位内膜中DNMT1、DNMT3A、DNMT3B的mRNA水平均明显低于对照内膜,差异均有统计学意义(P<0.05,P<0.01,);而在位内膜和异位内膜之间的差异无统计学意义(均P>0.05)。②各DNMTs mRNA表达水平均呈正相关,相关性系数分别为0.370(DNMT1 vs.DNMT3A,P=0.006)、0.306(DNMT1 vs.DNMT3B,P=0.025)、0.287(DNMT3A vs.DNMT3B,P=0.035)。③异位内膜中MBD1 mRNA表达水平明显低于在位内膜(P=0.027)和对照内膜(P<0.01),在位内膜与对照组内膜之间差异无统计学意义(P=0.540);在位内膜与异位内膜中MBD2与MBD3 mRNA表达水平明显低于对照内膜(均P<0.01),而在位内膜与异位内膜之间的差异无统计学意义(均P>0.05);3组内膜中MBD4的mRNA表达水平无显著差异(P=0.596)。④MBD2与MBD3 mRNA表达水平之间呈正相关,相关性系数为0.326(P=0.011),其余MBDs之间无相关性(均P>0.05)。⑤MBD2与DNMT1、DNMT3A的mRNA表达水平之间均呈正相关,相关性系数分别为0.294(P=0.027)、0.261(P=0.048),其余DNMTs与MBDs的mRNA表达水平之间无相关性(均P>0.05)。结论与正常子宫内膜相比,卵巢子宫内膜异位症患者的在位内膜和异位内膜中DNMTs和MBDs存在mRNA表达水平异常,且各DNMTs之间、MBD2与DNMT1、DNMT3A、MBD3的mRNA表达水平之间均呈正相关,其可能导致DNA甲基化水平的异常,从而参与卵巢子宫内膜异位症的发生。

Objective To investigate the mRNA expression levels of DNA methyltransferases(DNMTs)and methyl-CpG-binding domains(MBDs)in the ovarian endometriosis and correlation analysis between them.Methods RT-qPCR was used to detect the mRNA expression levels of DNMTs and MBDs in the eutopic endometrium and ectopic endometrium in 20 patients with ovarian endometriosis and the normal endometrium of 20 cases of cervical intraepithelial neoplasia(CIN)Ⅲ.The pearson correlation was used to analyze the correlation between DNMTs and MBDs.Results①The mRNA expression levels of DNMT1,DNMT3 A and DNMT3 B were significantly lower in eutopic endometrium and ectopic endometrium than in control endometrium(P<0.05,P<0.01),but there were no significant differences between eutopic endometrium and ectopic endometrium(P>0.05,respectively).②The mRNA expression levels of DNMTs were correlated with each other,and the correlation coefficients were 0.370(DNMT1 and DNMT3 A,P=0.006),0.306(DNMT1 and DNMT3 B,P=0.025),0.287(DNMT3 A and DNMT3 B,P=0.035).③The mRNA expression level of MBD1 was significantly lower in ectopic endometrium than in ectopic and control endometrium(P=0.027,P<0.01),and there was no significant difference between the ectopic endometrium and control endometrium(P=0.540).The MBD2 and MBD3 mRNA expression levels were significantly lower in eutopic endometrium and ectopic endometrium than in the control endometrium(P<0.01,respectively),and there was no significant difference between the eutopic and ectopic endometrium(P>0.05,respectively).There was no significant difference in the mRNA expression levels of MBD4 between the three endometriums(P=0.596).④The pearson correlation analysis showed that MBD2 mRNA expression level was significantly correlated with MBD3,and the correlation coefficient was 0.326(P=0.011).There was no significant correlation between the remaining MBDs mRNA expression levels(P>0.05,respectively).⑤The pearson correlation analysis showed that MBD2 mRNA expression level was significantly correlated with DNMT1 and DNMT3 A mRNA expression levels,and the correlation coefficients was 0.294(P=0.027)and 0.261(P=0.048),respectively.There was no significant correlation between the remaining DNMTs and MBDs mRNA expression levels(P>0.05,respectively).Conclusion Compared with normal endometrium,there are abnormal mRNA expression evels of DNMTs and MBDs in the eutopic and ectopic endometrium in patients with ovarian endometriosis,and there is positive correlation between DNMTs,MBD2 and DNMT1,DNMT3 A,MBD3 mRNA expression levels,which may be related to the occurrence of ovarian endometriosis by changing the levels of DNA methylation.