Yan, K.; Dong, W.; Wu, Y.; Han, Z.; Hong, J.; Ma, H.; Zhu, C.; Xiong, Y.; Yang, Z.

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. Methods: 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. Results: 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. Conclusions: 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.