REL and diffuse large B-cell lymphoma: The finding that NF-κB c-REL and the RELB/p52 heterodimer are independently required for the re-entry of light zone B cells into the dark zone, i.e., the putative normal cellular counterparts of GCB-DLBCL, suggests that those transcription factors may play a role in GCB-DLBCL pathogenesis [Figure 2].