The correlation between pre-S2 mutant and PD-L1 expression or Tregs infiltration in tumor tissues or other clinicopathological characteristics was evaluated and showed that the pre-S2 mutant-positive HCC patients were significantly associated with higher densities of PD-L1-expressing cells (median (range), 18.20 (6.96–32.38) versus 7.09 (3.45–18.07) cells/mm2; p value < 0.0001) and Tregs (median (range), 12.84 (8.05–19.60) versus 2.17 (0.89–6.96) cells/mm2; p value < 0.0001) in tumor tissues than the pre-S2 mutant-negative HCC patients (Table 2). The gene discussed is CD274; the disease is hepatocellular carcinoma.