Role of miR-137 in Notch1 mediated autophagy in proliferation and migration of hepatocellular carcinoma cells / 中华肝胆外科杂志

ABSTRACT

Objective To explore the role of miR-137 in the proliferation and migration of hepatocellular carcinoma (HCC) cells by regulating Notch1 and mediating autophagy.Methods The human SMMC7721 hepatoma cell line was transfected with miR-137 mimics,miR-137 inhibitor and Notch1 interfering RNA (siRNA),and divided into normal control group (NC group),miR-137 mimics group,miR-137 inhibitor group,Notch1 siRNA group.The expression levels of miR-137 and Notch1 mRNA after the transfection were detected by RT-PCR in SMMC7721 cells.Transwell experiments were performed to analyze the effect of miR-137 and Notch1 on the migration and invasion of SMMC7721 cells.The expression levels of β-catenin and vimentin in SMMC7721 cells were detected by immunohistochemistry.The number of autophagosomes was detected by double labeled adenovirus.Western blot was utilized to detect the expression of Notch1,E-Cadherin,N-Cadherin,vimentin,P62,and LC3.Results The results of RT-PCR showed that the relative expression level of Notch1 in miR-137 inhibitor group (5.71 ± 0.45) was significantly higher than that in miR-137 mimics group (0.21 ± 0.06) with statistical significance (P ＜ 0.05).The Transwell experiments showed that there were fewer invasive metastatic hepatoma cells in miR-137 mimics group (66.00 ± 4.55) and Notch1 siRNA group (88.00 ± 6.78) than that in the miR-137 inhibitor group (515.00 ±35.12) (P ＜0.05).The expression levels of β-catenin in miR-137 mimics group and Notch1 siRNA group were significantly increased and the expression level of vimentin was decreased (P ＜ 0.05).The results of autophagy double labeled adenovirus test showed that the number of autophagosomes in miR-137 mimics group (5.50 ± 3.70) was significantly fewer than that in miR-137 inhibitor group (32.75 ± 4.11),and the difference was statistically significant (P ＜ 0.05).The expression levels of Notch1,N-cadherin,vimentin,and LC3 protein in miR-137 mimics group were much lower than that in miR-137 inhibitor group and NC group,and the expression levels of E-Cadherin and P62 protein were greatly increased.The expression level of Notch1,N-cadherin,and LC3 protein in Notch1 siRNA group were significantly lower than that in NC group,and the expression levels of E-cadherin and P62 protein were much higher than that in NC group.Conclusion MiR-137 can inhibit the proliferation,migration and invasion of HCC cells by inhibiting the expression of Notch1 and autophagy,which may become a new target for the treatment of HCC.