PDCD1 and hepatocellular carcinoma: As expected, HCC patients with a better T + A treatment response (achieved PR/CR) had higher infiltration of TCF-1+ PD-1+ CD8+ T cells in the biopsy HCC tissues, while HCC patients without a response to T + A treatment showed lower accumulation of this cell subset in the biopsy HCC tissues (Fig. 6a, b).