Multiomics characterization of an alcohol-induced hepatocellular carcinoma mouse model

Hepatocellular carcinoma (HCC) is a major global health problem, ranking as the sixth most frequently diagnosed cancer and the third leading cause of cancer-related mortality worldwide. Although the incidence of viral infection-mediated HCC has decreased in recent years, the incidence of alcohol- and metabolic dysfunction-associated HCC has increased, driven by changes in lifestyle and diet. Excessive alcohol consumption contributes to advanced liver diseases, including liver fibrosis, cirrhosis and HCC. Despite the clinical relevance of alcohol-associated HCC, there are no suitable animal models that adequately reflect the pathophysiological features of alcohol-associated HCC in humans. Here, to address this limitation, we established a mouse model of alcohol-associated HCC through the combined administration of N-diethylnitrosamine and carbon tetrachloride (CCl₄), followed by administration of an alcohol-containing Lieber-DeCarli diet. The results indicated that chronic alcohol exposure in the presence of N-diethylnitrosamine and CCl₄ substantially accelerated HCC development, which was characterized by increased oxidative stress, inflammation and severe fibrosis. Furthermore, we found that chronic ethanol consumption disrupted hepatic immunity, characterized by natural killer/natural killer T cell depletion, increased PD1⁺CD8⁺ cells, reduced cytotoxicity and elevated inflammation. We also observed marked alterations in the gut microbiome following chronic alcohol administration. These immunological and microbiome alterations fostered an immunosuppressive microenvironment that accelerated HCC progression. Our newly developed mouse model induced liver tumorigenesis within a relatively short timeframe and recapitulated the clinical and pathological features of alcohol-associated HCC. The model therefore represents a valuable tool for studying the mechanisms underlying alcohol-associated HCC and related chronic liver diseases.