BIRC3 encodes cellular inhibitor of apoptosis protein 2 (cIAP2), a multi-functional E3 ubiquitin ligase that regulates apoptosis, inflammation, and cell survival pathways. The protein functions as a dual regulator of NF-κB signaling, positively regulating the canonical pathway while suppressing non-canonical NF-κB activation 1. BIRC3 promotes cell survival by preventing ripoptosome formation through ubiquitination of key targets including RIPK1 and CASP8, thereby inhibiting both apoptosis and necroptosis 1. In cancer contexts, BIRC3 demonstrates complex roles: it acts as a survival factor for senescent glioblastoma cells after radiotherapy, where SMAC mimetics targeting cIAP2 can eliminate these cells and prevent tumor recurrence 2. The gene shows elevated expression in glioma under endoplasmic reticulum stress, promoting cell survival and tumorigenesis 3. However, BIRC3 exhibits context-dependent functions, as genetic inactivation is associated with poor prognosis in chr11 lymphocytic leukemia, while overexpression correlates with glioma progression 4. BIRC3 also contributes to inflammatory responses in rheumatoid arthritis by regulating fibroblast-like synoviocyte survival and cytokine production 1, making it a promising therapeutic target across multiple diseases.