miR-139-5p and inhibits invasion and metastasis of hepatoma cells by targeting TGF-β1 / 中华肝胆外科杂志

ABSTRACT

Objective To investigate the molecular mechanism of miR-139-5p targeting transforming growth factor-β1 (TGF-β1) in the regulation of epithelial mesenchymal transition (EMT),thus inhibiting invasion and metastasis of hepatoma cells.Methods Bioinformatics methods were used to determine whether miR-139-5p was the best binding miRNA of TGF-β1.Correlation between the TGF-β1 expression as detected by immunohistochemistry and Western blot,and the miR-139-5p level by qRT-PCR in 56 hepatoma tissues and 20 normal tissues,respectively,was analyzed.The relationship between the miR-139-5p level as detected by qRT-PCR,and TGF-β1,E-cadherin and Vimentin by Western blot in the high and low metastatic hepatoma cell lines were investigated.In recombinant cell lines,whether miR-139-5p could bind to the 3'UTR site of TGF-β1 was evaluated,and the effect on invasive ability after modulating miR-139-5p level was also tested by the transwell method.Results A total of 20 miRNAs were found to be able to bind with TGF-β1 by bioinformatics methods and among these mRNAs,miR-139-5p was the best target miRNA with the highest specificity and strongest stability to bind TGF-β1.The positive expression rates of TGF-β1 in hepatoma tissues and adjacent normal liver tissues were 80.4％ (45/56) and 15.0％ (3/20),respectively,(P ＜0.05).There were significant differences on the expressions of TGF-β1,E-cadherin and Vimentin among the different metastatic cell lines (all P ＜ 0.05).After miR-139-5p was transfected into hepatoma cells,miR-139-5p could bind to the 3'UTR site of TGF-β1,resulting in downregulating TGF-β1 expression.When compared to the other three groups,the cell line with a high expression of miR-139-5p had a significantly lower count of invasive cells (53 ± 4/high magnification field) (P ＜ 0.05).Conclusion miRNA139-5p could specifically bind to the 3'UTR site of TGF-β1 and regulate the EMT signaling pathway,thus suppressing invasion and metastasis of hepatoma cells.