PDCD1 and hepatocellular carcinoma: The role of TOX is not clearly defined; however, it was noted that an abundance of TOX protein expression in CD8 T cells was associated with a high level of PD-1 ligands in HCC, leading to the suppression of T cell tumor fighting abilities by means of a reduction in PD1 degradation and promotion of PD1 translocation to the CD8 T cell surface.