A Metabolic Switch Controlling Liver Cancer Evolution from Senescent NASH Hepatocytes
Hepatocellular carcinoma (HCC), the third most common cancer, originates from differentiated hepatocytes undergoing compensatory proliferation in livers damaged primarily by viruses or nonalcoholic steatohepatitis (NASH). Here we identified the gluconeogenic enzyme fructose-1,6-bisphosphatase 1 (FBP1) as a TP53 target, induced in senescent NASH hepatocytes but downregulated in most human HCCs. Initial FBP1 downregulation in disease-associated hepatocytes, whose accumulation precedes HCC development5, activates AKT to inhibits GSK3 substrate binding, thereby augmenting activation of NRF2 which accelerates FBP1 and TP53 degradation. Intrinsic NRF2 activation and FBP1 loss trigger overlapping transcriptomic responses that suppress senescence, enhance hepatocyte proliferation and metabolism, and enable NRAS- or NASH-induced hepatocarcinogenesis. This AKT-dependent metabolic switch, operative in mice and humans, controls NASH to HCC progression. Our results further suggest that NASH-related hepatocyte senescence is triggered by hypernutrition-induced single strand DNA breaks. Senescence reversal enables HCC progenitor expansion and somatic mutagenesis.