Research Paper Volume 11, Issue 15 pp 5593—5612

TGFβ1- miR-140-5p axis mediated up-regulation of Flap Endonuclease 1 promotes epithelial-mesenchymal transition in hepatocellular carcinoma

Figure 5. FEN1 is a direct target of miR-140-5p in HCC cells. (A) miR-140-5p and its putative binding sequence in the wild-type and mutant 3′-UTR of FEN1. (B) Overexpression of miR-140-5p significantly decreased the luciferase activity of constructs with wild type (WT) but not mutant (MUT) FEN1 3′-UTR in HEK-293 cells, **P < 0.01. (C) RT-qPCR showed that miR-140-5p mRNA was significantly increased in HCC cells transfected with lentiviral vector, **P < 0.01. (D) RT-qPCR showed that FEN1 mRNA was significantly decreased in HCC cells transfected with miR-140-5p vector, **P < 0.01. (E) Relative mRNA expression of miR-140-5p in HCC cells overexpressing miR-140-5p transfected with miR-140-5p inhibitors or NC, **P < 0.01. (F) Relative mRNA expression of FEN1 in HCC cells overexpressing miR-140-5p transfected with miR-140-5p inhibitors or NC, **P < 0.01. (G) Overexpression of miR-140-5p markedly suppressed FEN1 protein levels in HCC cells, and miR-140-5p inhibitors reversed the effect. (H) The expression of miR-140-5p in HCC tissues and the paired adjacent tissues was determined by RT-qPCR, **P < 0.01. (I) RT-qPCR analysis of miR-140-5p mRNA expression, n = 10 for HCC with metastasis and n = 11 for HCC without metastasis, *P < 0.05. (J) The correlation between miR-140-5p and FEN1 mRNA expression using Pearson’s correlation analysis. (K) Low expression of miR-140-5p indicated poor overall survival in the KM-plotter database.