Inhibition of SIRT1 in HCC cells, either through knockdown or administration of SIRT1 inhibitors, led to decreased tumor development in vitro and in vivo and exerted cytostatic as opposed to a cytotoxic effect (42, 44), while SIRT1 overexpression accelerated HCC growth (44). The gene discussed is SIRT1; the disease is hepatocellular carcinoma.