In CD8 effector T‐cells, Blimp‐1 supports terminal differentiation along with high expression of effector molecules such as granzyme B.39, 40Interestingly, IL‐2‐induced cytotoxicity in tumour‐specific cytotoxic CD4 T‐cells equally depends on Blimp‐1 expression for optimal granzyme B expression, suggesting that Blimp‐1 is generally required for the cytotoxic programme in T‐cells.41 This evidence concerns the gene PRDM1 and neoplasm.