Metformin has shown great promise in the treatment of HCC. Radiofrequency ablation (RFA) deficiency results in recurrence and metastasis of remaining HCC tumors. Here, we aimed to investigate the role and mechanism of metformin in HCC after RFA deficiency. HCC cell line Hep-G2 was selected to simulate RFA deficiency and named HepG2-H cells. After treating cells with different concentrations of metformin (2.5, 5, 10 μM) or transfecting related plasmids, cell proliferation, migration, invasion, apoptosis and angiogenesis were detected, in vitro permeability test was performed, and an angiogenesis-related protein VEGFA was analyzed. The residual HCC model after RFA deficiency was established in mice. Metformin was administered by gavage to detect changes in tumor volume and weight, and CD31 staining was used to observe microvessels. The targeting relationship between miR-302b-3p and TXNIP was demonstrated by the bioinformatics website, dual-luciferase reporter assay, and RNA pull-down assay. The results found that metformin inhibited RFA deficiency-induced growth and angiogenesis of HCC cells in vitro. miR-302b-3p counteracted the therapeutic effect of metformin on RFA deficiency. miR-302b-3p targeted regulation of TXNIP. The up-regulation of TXNIP reversed the effects of overexpression of miR-302b-3p on RFA-deficient HCC cells. Metformin inhibited RFA-deficiency-induced HCC growth and tumor vascular abnormalities in vivo. Overall, metformin promotes the normalization of abnormal blood vessels after RFA deficiency in HCC by miR-302b-3p targeting TXNIP, which can be used to prevent the progression of HCC after RFA.
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