PRDM1 and diffuse large B-cell lymphoma: Interestingly, the human PRDM1 gene is frequently mutated on both alleles in activated B cell‐like diffuse large B cell lymphoma (ABC‐DLBCL), demonstrating that loss of the tumor‐suppressor gene PRDM1 contributes to lymphomagenesis by preventing plasma cell differentiation (Pasqualucci et al, 2006; Tam et al, 2006).