Hepatocellular Carcinoma Revisited from Single Cell Sequencing: Dynamic Evolution from Epithelial Dedifferentiation to Mesenchymal Remodeling

Background Single-cell RNA sequencing has provided new insights into hepatocellular carcinoma (HCC); however, a unified understanding of epithelial heterogeneity and immune evasion strategies in HCC remains lacking.

We re-analyzed publicly available single-cell datasets using conventional bioinformatics pipelines. Cell-type annotation of epithelial and T cell populations was further validated across multiple independent datasets to ensure robustness.

We systematically examined epithelial, immune, myeloid, and stromal lineages. In addition to recapitulating previously reported findings, we identified several novel observations. Notably, we uncovered a three-step dedifferentiation trajectory in epithelial cells and confirmed a bidirectional differentiation pattern within CD8□ T cells. We also identified a subset of GZMK□ CD4□ T cells, whose transcriptional features resemble but are distinct from T follicular helper (Tfh) cells. Importantly, transcriptional drift within myeloid populations appeared to be closely associated with immune responsiveness. Furthermore, ligand–receptor analysis highlighted a potential cooperative role of LAMP3□ dendritic cells and Tfh cells in promoting lymphoid follicle formation.

In the era of rapidly evolving single-cell sequencing technologies, we provide a framework for understanding cellular heterogeneity in HCC, which awaits further validation in future studies. Competing Interest Statement The authors have declared no competing interest. Footnotes Y.X. provided bioinformatics guidance. Z.H. and H.M. were responsible for data collection. W.D. and Z.Y. designed the study. K.Y., Y.W., and C.Z. performed the bioinformatics analyses. K.Y. and J.H. drafted the manuscript. All authors read and approved the final manuscript.