GZMB and hepatocellular carcinoma: The fifth cluster (C4‐GADD45β) was almost solely detected in tumour samples (∼91.33% of total HCC‐infiltrating γδ T cells) and highly expressed stress marker genes such as GADD45γ and GADD45β, along with the exhaustion marker gene LAG3 and cytotoxicity genes such as NKG7, GNLY, GZMB and IFNG, representing an exhausted, yet cytotoxic, population within HCC tumours.