The prognostic value of MMP1, ITGA2, P3H1, and CTSA in HCC are demonstrated using databases from TCGA-LIHC, ICGC, and GSE54236 HCC datasets (Supplementary Figures 1–3), which demonstrated that the four genes’ predictive value for HCC prognosis to a certain extent, though not as significant as the risk model overall. This evidence concerns the gene CTSA and hepatocellular carcinoma.