TRAF2 and plasma cell myeloma: The analysis of TRAFs or cIAPs mutant multiple myeloma and cIAPs- or TRAFs-deficient MEFs demonstrated that NIK degradation is ensured by the TRAF3-TRAF2-cIAP1 ubiquitin ligase complex, in which TRAF3 serves as NIK-binding component and recruits cIAPs via TRAF2 [63,141].