PDCD1 and hepatocellular carcinoma: The expression of ZSCAN20 had a significant relationship with CD274 expression (R = 0.25 P = 1.5E-06), CTLA4 (R = 0.19, P = 1.9E-04) and PDCD1 (R = 0.14, P = 6.6E-03) in HCC (Figure 9D).