PVR and hepatocellular carcinoma: We first compared the gene expression level of each member of the TIGIT/DNAM-1 axis in HCC (N = 683) and in NT (N = 319) tissues: TIGIT, DNAM-1, TACTILE, PVRIG, and KIR2DL5A and their ligands PVR, NECTIN-1, NECTIN-2, and NECTIN-3 (Figure 2A).