In hepatocellular carcinoma (HCC), the most prevalent form of liver cancer [61], SIRT7 spurs the advancement of the G1/S cell cycle phase by stimulating the expression of favorable drivers of cell cycle progression such as Cyclin D1 while concurrently repressing cell cycle inhibitors such as p21WAF1/Cip1 (Fig. 2A and Table 1) [57]. The gene discussed is SIRT7; the disease is hepatocellular carcinoma.