1.miR-377-5p inhibits proliferation and invasion of hepatocellular carcinoma HepG2 cells by down-regulating HIF-1α and related VEGFsignaling pathway
YANG Jin ; HE Kai ; ZHANG Mengyu ; WU Lile ; QIN Shu ; FENG Chunhong ; LUO Ming ; XIA Xianming
Chinese Journal of Cancer Biotherapy 2020;27(3):248-254
Objective:To explore the targeting relationship between miR-377-5p and hypoxia inducible factor-1 (HIF-1α), and investigate the regulatory effect of miR-377-5p on proliferation, invasion and epithelial-mesenchymal transition (EMT) of hepatocellular carcinoma (HCC) cells through vascular endothelial growth factor (VEGF) signaling pathway. Methods: :The expression of miR-377-5p in 35 pairs of human HCC tissues and para-cancerous tissues was detected by qPCR. Then, HepG2 cells were divided into control group, mimic-NC group and miR-377-5pmimicgroup.qPCRwasusedto detect the transfection efficiency; the effects of miR-377-5p over-expression on proliferation and invasion of HepG2 cells were examined by EdU staining and Transwell assay, respectively; and the effect of miR-377-5p over-expression on the expressions of proliferation-related protein Ki-67, proliferating cell nuclear antigen (PCNA) and epithelial-mesenchymal transition (EMT) markers (E-cadherin and N-cadherin) were detected by Western blotting (WB); the effect of miR-377-5p over-expression on the expression of hypoxia inducible factor-1α (HIF-1α) in HepG2 cells was detected by qPCR and WB; and the targeting relationship between miR-377-5p and HIF-1α gene was determined by Luciferase reporter gene assay. Results: The expression of miR-377-5p in HCC tissues was significantly lower than that in para-cancerous tissues (P<0.01). Compared with the control group, the expression of miR-377-5p in HepG2 cells of miR-377-5p mimic group elevated significantly, and the proliferation, invasion and the expression of N-caderin proteins decreased,significantly (all P<0.01), while the expression of E-caderin increased significantly (P<0.01). At the same time, the mRNA and protein expressions of HIF-1α in miR-377-5p mimic group decreased significantly (P<0.01 or P<0.05). miR-377-5p targetedly inhibited the expression of HIF-1α gene and suppressed the activation of VEGF pathway (all P<0.05). Conclusion: miR-377-5p inhibits the proliferation, invasion and EMT of HepG2 cells via targetedly inhibiting HIF-1α expression and suppressing the activation of VEGF signaling pathway.