H19 regulates angiogenic capacity of extravillous trophoblasts by H19/miR-106a-5p/VEGFA axis

Purpose To investigate the role and underlying mechanism of H19 in regulating angiogenic capacity of extravillous trophoblasts. Methods Gain and loss of function experiments were performed using a human first-trimester extravillous trophoblast (EVT) cell line, HTR-8/SVneo cells. H19 was overexpressed or knocked down in HTR-8 cells by transfecting plasmid harboring whole-length H19 sequence (pH19) or siRNA specially targeting H19, respectively (siH19). Cell migration and tube-formation assay were assessed in the indicated groups. Gene expression was detected by RT-qPCR, Western blot, and ELISA assay. Results Overexpression of H19 in EVT cells increased cell migration and tube formation, while downregulation of H19 in EVT cells decreased cell migration and tube formation. Furthermore, we found that H19 played its role by VEGFA. In addition, we demonstrated the H19/miR-106a-5p/VEGFA regulatory axis in EVT. Experiments of the clinical specimen showed that H19 was very abundantly expressed in human first-trimester trophoblasts, and we found that the expression of H19 and VEGFA were significantly downregulated in the villous tissues from idiopathic recurrent miscarriage (RM) patients; moreover, the expression of H19 and VEGFA was positively correlated. Conclusion H19/miR-106a-5p/VEGFA axis plays a role in regulating the angiogenic capacity of EVT, which might contribute to idiopathic RM.