Single-Cell Transcriptomic Profiling Reveals Immunometabolic Reprogramming and Cell-Cell Communication in the Tumor Microenvironment of Human Hepatocellular Carcinoma.

Hepatocellular carcinoma (HCC) is sustained by coordinated interactions among malignant hepatocytes, immune cells, and stromal populations that collectively drive tumor growth, immune evasion, and vascular remodeling. Using integrative single-cell transcriptomics on 93,032 cells from tumor and healthy human liver, we characterized cell-type-specific transcriptional programs underlying immunometabolic reprogramming and reconstructed the intercellular communication circuits that maintain the tumor microenvironment. Malignant hepatocytes displayed upregulation of genes encoding both glycolytic and oxidative phosphorylation (OXPHOS) metabolic enzymes, consistent with metabolic plasticity, while concurrently suppressing genes involved in antigen presentation-a transcriptional pattern indicative of coordinated metabolic and immune-evasive reprogramming. Tumor-associated macrophages acquired TREM2-enriched, lipid-handling phenotypes consistent with immunosuppressive polarization, and tumor endothelial cells upregulated angiocrine and extracellular matrix programs while silencing innate immune outputs. Ligand-receptor inference revealed a qualitative rewiring of intercellular communication: the antigen-presentation-centered network of the healthy liver was replaced by a tumor-driven architecture dominated by pro-angiogenic, ECM-integrin, inflammatory chemokine, and lipid-associated signaling circuits, with malignant hepatocytes, TAMs, and TECs collectively assuming the dominant signaling burden. These findings establish that HCC progression is an emergent property of a stabilized multicellular network, rather than the autonomous behavior of malignant cells, and define cooperative immunometabolic modules that constitute tractable targets for combinatorial therapeutic intervention.