Fig. 4

STAT3 regulates autophagy in trophoblast cells under hypoxic conditions. A Significant increases in STAT3 mRNA were found in JAR, JEG-3 and HTR-8 cells transfected with a STAT3 overexpression plasmid compared to untreated cells (Mock) or empty vector (Vec)-transfected cells under hypoxic conditions by qRT-PCR. B The three trophoblast cell lines were transfected with a STAT3 overexpression plasmid under hypoxic conditions, and MMP2, MMP9, P62 and LC3 expression levels were tested by western blotting analysis. Untreated trophoblast cells (Mock) and empty vector (Vec) cells served as controls. C Cell proliferation was evaluated by a CCK-8 assay. The three trophoblast cell lines were transfected with a STAT3 overexpression plasmid or empty vector under hypoxic conditions. Trophoblast cells cultured alone served as controls. D Trophoblast cells were transfected with a STAT3 overexpression plasmid or empty vector under hypoxic conditions, and invasion abilities were determined by Transwell assay. The number of penetrated cells was counted and analysed statistically. *P < 0.05, **P < 0.01, ***P < 0.001