Abstract
Bacterial metabolites play a dual role in hepatocellular carcinoma (HCC), exhibiting both tumor-promoting and tumor-suppressing activities dictated by their structural diversity. This review synthesizes recent advances in understanding how key microbial metabolites-such as bile acids, short-chain fatty acids, and polyamines-remodel the tumor immune microenvironment through mechanisms including immunometabolic reprogramming, epigenetic modification, and regulation of signaling pathways (e.g., FXR, TLR, and mTOR). We highlight their roles in modulating the function of T cells, NK cells, and tumor-associated macrophages and discuss emerging strategies that target these metabolites-including probiotic interventions, fecal microbiota transplantation, and metabolite-based adjuvants-to enhance immunotherapy efficacy and overcome resistance. By integrating mechanistic insight into translational potential, this work outlines a metabolite-immunometabolism-hepatocarcinogenesis framework and proposes novel combinatorial approaches for HCC treatment.