Regulatory role of microRNA‐320a in the proliferation, migration, invasion, and apoptosis of trophoblasts and endothelial cells by targeting estrogen‐related receptor γ

Abstract Recently, microRNAs (miRNAs) have been demonstrated to participate in many physiological and biological processes, especially by acting as circulating biomarkers or modulators in cell differentiation. Therefore, the aim of the current study was to clarify whether microRNA‐320a (miR‐320a) regulates the proliferation, migration, invasion, and apoptosis of trophoblasts and endothelial cells. In this study, miR‐320a mimics and inhibitors were transfected into HTR.8/SVneo cells and human umbilical vein endothelial cells (HUVECs) using liposomes. Subsequently, the expression of miR‐320a and estrogen‐related receptor γ (ERRγ) mRNA was detected by a reverse transcription quantitative polymerase chain reaction, whereas the protein expression of ERRγ, vascular endothelial growth factor (VEGF), angiogenin 1 (Ang‐1), human 3beta‐hydroxysteroid dehydrogenase type 1 (HSD3B1), and human chorionic gonadotropin (HCG) was detected by western blot analysis. Furthermore, the proliferation, invasion/migration, and apoptosis of cells were analyzed by the cell counting kit‐8 assay, transwell assay, and flow cytometry, respectively. The results showed that overexpression of miR‐320a decreased the optical density (OD) values and the proliferation rate of HTR.8/SVneo cells and HUVECs, while inhibiting the expression of VEGF, Ang‐1, HSD3B1, and HCG in these cells. Furthermore, miR‐320a reduced the ability of cell invasion and migration, while increasing the rate of cell apoptosis. After cotransfecting the cells with miR‐320a and ERRγ small (or short) interfering RNA (siRNA), the decreased ERRγ expression led to inhibited proliferation, migration, and invasion, but increased apoptosis of HTR.8/SVneo cells and HUVECs. Our results further revealed that miR‐320a induced the apoptosis of trophoblasts and endothelial cells while inhibiting their proliferation, migration, and invasion by decreasing the expression of ERRγ and by indirectly suppressing the expression of VEGF, Ang‐1, HSD3B1, and HCG.