Jin Meiyuan, Li Haiyang, Xu Hongfeng, Huo Gaoxiang, Yao Yingyu
Department of Obstetrics, Tongde Hospital of Zhejiang Province Hangzhou, China.
Department of Gynaecology and Obstetrics, Zhoushan Municipal Women and Children Health Care Center Zhoushan, China.
Int J Clin Exp Pathol. 2017 Nov 1;10(11):10901-10909. eCollection 2017.
Insufficient trophoblast migration/invasion is associated with the preeclampsia (PE) development. Recently, microRNAs (miRNAs) have been confirmed to be involved in the pathogenesis of PE. The aim of the present study was to evaluate whether miRNAs is involved in the procession of PE by regulating the migration/invasion of trophoblast. First, we compared the expression profiles of miRNAs between normal and preeclamptic placentas using microarray. Validation analysis of miR-20b level in placentas and peripheral blood specimens was performed using quantitative reverse transcription PCR (qRT-PCR). Then, the effects of miR-20b on trophoblast cell migration and invasion were evaluated using wound healing assay and transwell migration assay. Further bioinformatics analysis, luciferase reporter assays and Western blot were performed to identify its target genes. The correlation between miR-20b and matrix metalloproteinase-2 (MMP-2) in placentas was determined by Pearson's correlation coefficient. Finally, HTR8/SVneo cells were co-transfected with miR-20b inhibitor and si-MMP-2 to explore the molecular mechanism by which miR-20b functions in the trophoblast migration/invasion. We found that miR-20b was elevated in placentas and peripheral blood specimens from preeclampsia patients. Further results show that overexpression of miR-20b significantly inhibited the invasiveness of human trophoblast cells, whereas miR-20b knockdown enhanced trophoblast cell invasion. Matrix metalloproteinase-2 (MMP-2), the most common enzymes in remodeling extracellular matrix components for metastasis, was proved to be a direct target of miR-20b. Inhibition of MMP-2 by siRNA could reverse the promoting effect of miR-20b inhibition on the invasion of trophoblast cells. Taken together, our study indicates that miR-20b inhibited trophoblastic invasion by targeting MMP2. The miR-20b/MMP-2 axis may provide novel insights into understanding the molecular pathogenesis of PE and may be a prognostic biomarker and therapeutic target for PE.
滋养层细胞迁移/侵袭不足与子痫前期（PE）的发生发展相关。近年来，微小RNA（miRNA）已被证实参与子痫前期的发病机制。本研究旨在评估miRNA是否通过调节滋养层细胞的迁移/侵袭参与子痫前期的进程。首先，我们使用基因芯片比较了正常胎盘和子痫前期胎盘之间miRNA的表达谱。采用定量逆转录PCR（qRT-PCR）对胎盘和外周血标本中miR-20b水平进行验证分析。然后，使用伤口愈合试验和Transwell迁移试验评估miR-20b对滋养层细胞迁移和侵袭的影响。进一步进行生物信息学分析、荧光素酶报告基因检测和蛋白质印迹法以鉴定其靶基因。通过Pearson相关系数确定胎盘组织中miR-20b与基质金属蛋白酶-2（MMP-2）之间的相关性。最后，将miR-20b抑制剂和si-MMP-2共转染至HTR8/SVneo细胞，以探讨miR-20b在滋养层细胞迁移/侵袭中发挥作用的分子机制。我们发现，子痫前期患者胎盘和外周血标本中miR-20b水平升高。进一步结果显示，miR-20b过表达显著抑制人滋养层细胞的侵袭能力，而敲低miR-20b则增强滋养层细胞的侵袭能力。基质金属蛋白酶-2（MMP-2）是重塑细胞外基质成分以实现转移的最常见酶，被证明是miR-20b的直接靶标。通过siRNA抑制MMP-2可逆转miR-20b抑制对滋养层细胞侵袭的促进作用。综上所述，我们的研究表明miR-20b通过靶向MMP2抑制滋养层细胞侵袭。miR-20b/MMP-2轴可能为理解子痫前期的分子发病机制提供新的见解，并且可能成为子痫前期的预后生物标志物和治疗靶点。
