SIRT1 (degree = 12) functions as a context-dependent metabolic rheostat, exhibiting stage-specific duality: during early hepatocarcinogenesis it activates AMPK to suppress SREBP1c/FASN-driven lipogenesis, whereas in advanced HCC it stabilizes HIF-1α through deacetylation to potentiate glycolytic flux and lipid droplet storage [46, 47]. The gene discussed is FASN; the disease is hepatocellular carcinoma.