Finally, four out of the eight genes (COL5A1, CDK4, MMP2, and HLA-DQB1) were used for the further diagnosis and prognosis of HBV-associated HCC due to their stage-characterized signatures and remarkable consistency in expression levels in other independent samples (Figure 4a; Supplementary Figure S3). Here, COL5A1 is linked to hepatocellular carcinoma.