Research question

What is the mechanism of hypermethylation of runt-related transcription factor 3 (RUNX3) in the eutopic endometrium of endometriosis as biomarker in the malignant transformation of endometriosis?

Design

Methylation-specific polymerase chain reaction was used to analyse the methylation status of RUNX3 in endometriosis-associated ovarian cancer (EAOC). Primary eutopic endometrial stromal cells (ESC) were isolated from the uteri of patients with ovarian endometriosis. After RUNX3 knockdown by RNA interference technology or ESC treated with oestradiol, the proliferation and invasion ability were evaluated in ESC by using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) and transwell assays.

Results

The frequency of methylation of RUNX3 in neoplastic tissue in the EAOC group was significantly higher than that in the ectopic endometrium of the endometriosis group (P < 0.001), and the frequency of methylation of RUNX3 in the eutopic endometrium of the EAOC group was significantly higher than that in the endometriosis group (P < 0.001). However, there was no significant difference in the eutopic endometrium when compared between the endometriosis group and the control endometrium group (P = 0.233). Silencing RUNX3 promoted the proliferation and invasion of ESC (P < 0.001 and P < 0.001). Following intervention with oestrogen, it was observed that the oestradiol group showed higher levels of RUNX3 methylation (P < 0.001) and DNA methyltransferase 1 (DNMT1) mRNA and protein expression (P < 0.001 and P < 0.001), and lower RUNX3 mRNA and protein expression when compared with the ESC group (P < 0.001 and P < 0.001).

Conclusion

This study demonstrated that hypermethylation of the RUNX3 was related to the malignant transformation of endometriosis and that this process was related to corresponding changes in the eutopic endometrium. Furthermore, the ‘oestrogen-DNMT1’ signalling pathway may induce the hypermethylation of RUNX3 to promote the malignant transformation of endometriosis.

中文翻译：

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雌激素上调DNMT1并导致RUNX3高甲基化在卵巢子宫内膜异位症恶变中的作用

研究问题

子宫内膜异位症在位子宫内膜中runt相关转录因子3（RUNX3）高甲基化作为子宫内膜异位症恶变的生物标志物的机制是什么？

设计

甲基化特异性聚合酶链反应用于分析RUNX3在子宫内膜异位症相关卵巢癌 (EAOC) 中的甲基化状态。从卵巢子宫内膜异位症患者的子宫中分离出原发性在位子宫内膜基质细胞 (ESC)。通过RNA干扰技术敲低RUNX3或用雌二醇处理ESC后，使用3-(4,5-二甲基噻唑-2-基)-2,5-二苯基溴化四唑(MTT)和transwell评估ESC中的增殖和侵袭能力化验。

结果

EAOC组肿瘤组织中RUNX3甲基化频率显着高于异位内膜异位内膜（P  < 0.001），EAOC组在位内膜RUNX3甲基化频率显着升高优于子宫内膜异位症组（P  < 0.001）。但子宫内膜异位症组与对照组子宫内膜组在位内膜差异无统计学意义（P  =0.233）。沉默 RUNX3 促进了 ESC 的增殖和侵袭 ( P  < 0.001 and P < 0.001)。雌激素干预后，观察到雌二醇组RUNX3甲基化（P  < 0.001）和 DNA 甲基转移酶 1（DNMT1） mRNA 和蛋白表达水平较高（P  < 0.001 和P  < 0.001），而 RUNX3 mRNA 和蛋白水平较低与 ESC 组相比的表达 ( P  < 0.001 和P  < 0.001)。

结论

该研究表明RUNX3的高甲基化与子宫内膜异位症的恶性转化有关，并且该过程与在位子宫内膜的相应变化有关。此外，“雌激素-DNMT1”信号通路可能会诱导RUNX3的高甲基化，从而促进子宫内膜异位症的恶变。