早发型重度子痫前期患者胎盘组织Wnt信号通路抑制因子SFRP4基因甲基化水平及其差异表达

Methylation level and differential expression of SFRP4 gene,an inhibitor of Wnt signaling pathway,in placental tissues of patients with early onset severe preeclampsia

目的 探究早发型重度子痫前期(EOSPE)患者胎盘组织Wnt信号通路抑制因子SFRP4基因甲基化水平及其差异表达。方法 回顾性分析海口市第四人民医院2017年1月至2022年1月收治的具有完整资料的EOSPE病例80例,EOPE病例70例,经1∶1倾向性匹配评分后最终纳入研究EOSPE和EOPE病例各41例。定量PCR和免疫组化检测41例EOSPE孕妇和41例EOPE孕妇胎盘中SFRP4的mRNA和蛋白的表达情况,并采用甲基化特异性PCR(MSPCR)检测SFRP4甲基化情况。并同时使用RT-qPCR和免疫组化检测Wnt信号通路下游Wnt1和Wnt2的mRNA和蛋白表达。构建过表达SFRP4慢病毒转染滋养细胞HTR-8细胞,CCK-8、划痕实验和Transwell小室侵袭实验检测过表达SFRP4的HTR-8细胞的增殖、迁移和侵袭能力。结果 EOSPE组胎盘中的SFRP4的mRNA和蛋白表达均显著高于EOPE组,而EOSPE组胎盘组织的SFRF4甲基化率显著低于EOPE组(17.14%vs 63.33%,P=0.000),SFRF4蛋白表达水平与其启动子区域的甲基化程度呈负相关(r=-0.822,P=0.000)。EOSPE组胎盘组织的Wnt1和Wnt2的mRNA和蛋白表达均显著低于EOPE组。过表达SFRP4的HTR-8细胞增殖和侵袭能力显著下降。结论 SFRP4在EOSPE中甲基化水平降低,且SFRP4表达增加,抑制Wnt信号通路促进EOSPE的发病。

Objective To investigate the methylation level and differential expression of Wnt signaling pathway inhibitor SFRP4 gene in placental tissue of patients with early-onset severe preeclampsia(EOSPE).Methods A retrospective analysis of 80 EOSPE cases and 70 EOPE cases with complete data admitted to our hospital from January 2017 to January 2022 was performed,and 41 EOSPE and 41 EOPE cases were finally included in the study after a 1:1 propensity matching score.The expression of SFRP4 in placenta of 41 pregnant women with EOSPE and 41 pregnant women with EOPE were detected by quantitative PCR and immunohistochemistry.The methylation of SFRP4 was detected by methylation-specific PCR(MSPCR).The mRNA and protein expression of Wntl and Wnt2 downstream of Wnt signaling pathway were detected by RT-qPCR and immunohistochemistry.SFRP4 overexpression lentivirus was constructed to transfect trophoblast HTR-8 cells,and the proliferation,migration and invasion ability of HTR-8 cells overexpressing SFRP4 were detected by CCK-8,scratch assay and transwell chamber invasion assay.Results The mRNA and protein expression of SFRP4 in placentas of EOSPE group was significantly higher than that of EOPE group,and the methylation rate of SFRF4 in placenta of EOSPE group was significantly lower than that of EOPE group(17.14%vs 63.33%,P=0.000).The expression level of SFRF4 protein was negatively correlated with the methylation degree of its promoter region(r--0.822,P=0.000).The mRNA and protein expressions of Wntl and Wnt2 in EOSPE group were significantly lower than those in EOPE group.The proliferation ability and invasion ability were significantly decreased when HTR-8 overexpressed SFRP4.Conclusion The methylation level of SFRP4 was decreased in EOSPE,and the expression of SFRP4 was increased,and the inhibition of methylation regulates the Wnt signaling pathway and promotes the pathogenesis in EOSPE.