SIRT1 and hepatocellular carcinoma: In hepatoma, EGCG enhances the cancer cell sensitivity to ionizing radiation treatment via miR-34a/Sirt1/p53 signaling pathway regulation [152]; in hepatocellular carcinoma, the tumor suppressors let-7a and miR-34a are upregulated [153], and in HepG2 cells it has been shown that this molecule acts on several miRs, causing either their up- (13 miR) or down- (48 miR) regulation [154].