Diet-Microbiota-Immune Interactions in Hepatocellular Carcinoma: An Immunometabolic and Spatial Perspective

Hepatocellular carcinoma (HCC) is the most frequent type of primary liver cancer and one of the leading causes of cancer-related mortality globally, with its incidence increasingly driven not only by viral hepatitis and alcohol-related etiologies but also by metabolic dysfunction-associated steatotic liver disease. Dietary intake can modify gut microbial activity and the production of microbial metabolites, which in turn may regulate hepatic immune signaling and metabolic pathways along the gut-liver axis. Microbiota-derived metabolites have emerged as important immunometabolic mediators linking dietary factors to hepatic immune responses and metabolic reprogramming. These metabolites, which have been shown to influence hepatic immune cell function and inflammatory signaling, include short-chain fatty acids, secondary bile acids, and tryptophan-derived indoles. Changes in the production and composition of these metabolites have been associated with immune dysregulation, chronic inflammation, and metabolic reprogramming that promote hepatocellular carcinoma development. This review highlights how diet-microbiota interactions reshape hepatic immunometabolism and discusses their potential translational relevance for prevention and therapeutic strategies in hepatocellular carcinoma.