S100A9 and hepatocellular carcinoma: Through down-dimensional analysis, we identified 18 cell types in this single-cell sequencing dataset (Fig. 7A), with low expression of CLEC3B and GNA14 in various cell types, high expression of CYP2C9 in hepatocytes, high expression of NQO1 in epithelial and hepatocytes, high expression of NT5DC2 in epithelial and endothelial cells, and high expression of S100A9 in multiple cell types, suggesting a role in HCC prognosis (Fig. 7B).