GZMB and hepatocellular carcinoma: Total levels of global circulating CD8+ T cells were elevated in HBV-associated HCC compared with non-HBV HCC [30], and a study reported lower levels of INF-γ, TNF-α, and granzyme B secretion in patients with HBV-associated HCC compared with non-HBV HCC [37], indicating impaired effector function of CD8+ T cells.