ALKBH5 inhibits trophoblast invasive ability in vitro and trophoblast outgrowth in a villous explant culture model. (A and B) QRT-PCR and western blotting analyses were performed to determine the levels of ALKBH5 in HTR-8 cells transfected with siCtrl, siALKBH5-1, siALKBH5-2, siALKBH5-3, control vector, or ALKBH5-overexpressing vector after 48 h. (D and E) ALKBH5 knockdown in HTR-8 cells increased trophoblast invasion compared to that of the control cell line. The invasive ability of the cells was assessed by Image-Pro Plus 6.0 software. (Panel: original magnification × 200 magnification). (F and G) ALKBH5 overexpression significantly reduced cell invasion compared to that of the vector control cell line. The invasive ability of the cells was assessed by Image-Pro Plus 6.0 software. (Panel: original magnification × 200 magnification). (H) Extravillous explants were obtained from HCs and RM patients at 6-10 weeks of gestation and cultured on Matrigel. Serial pictures of the explants were taken under a light microscope after 24 h and 72 h of culture in vitro. (I) Extravillous explants from RM at 6-10 weeks of gestation were maintained in culture on Matrigel. Serial pictures of the explants transfected with siALKBH5 or siCtrl were taken under a light microscope after 24 h and 72 h of culture in vitro.