GZMB and hepatocellular carcinoma: The density of granzyme B-expressing cells in HCC tissues was significantly lower in patients with either deletion spanning pre-S2 gene segment or high percentage of pre-S2 plus pre-S1 + pre-S2 deletion than those without (mean ± SEM, 2.55 ± 0.32 versus 8.83 ± 1.19 cells/mm2, P < 0.0001; 2.29 ± 0.36 versus 7.48 ± 1.03 cells/mm2, P = 0.0006, respectively) (Fig. 4C,D; left graphs).