PRDM1 and neoplasm: Another confirmation of the pro-tumorigenic activity of Tregs has been observed by Sawant DV et al., as they have seen that the accumulation of Tregs within the tumor core hinders the infiltration and effector function of CD8+ T cells through upregulation of the “B lymphocyte-induced maturation protein-1” (BLIMP-1) inhibitory receptor axis [127].