NCBP2 (nuclear cap binding protein subunit 2) is a core component of the cap-binding complex (CBC) that binds co-transcriptionally to the 5' m7G cap of pre-mRNAs [UniProt]. In the CBC, NCBP2 recognizes capped RNAs but requires NCBP1 to stabilize the complex into a high-affinity cap-binding state [UniProt]. The CBC-NCBP2 complex mediates multiple RNA metabolism processes: it promotes mRNA splicing, nonsense-mediated decay (NMD), and nuclear export by recruiting the TREX machinery through ALYREF interaction 1. The complex also regulates microRNA biogenesis and acts as a negative regulator of mRNA deadenylation [UniProt]. In cancer, NCBP2 shows aberrant expression across multiple tumor types, with increased expression in 24 of 32 cancer types examined 2. High NCBP2 expression is associated with worse overall survival, disease-specific survival, and progression-free survival in pancreatic adenocarcinoma and endometrial carcinoma 2. In oral squamous cell carcinoma, NCBP2 depletion reduces cell proliferation, migration, and invasion 3. In head and neck squamous cell carcinoma, NCBP2 expression inversely correlates with immune infiltration and immunotherapy response, with NCBP2 knockdown upregulating CCL4/CCL5 chemokines 4. Additionally, the antisense RNA NCBP2-AS2 regulates ovarian cancer stem cell activity through the MEK/ERK/STAT3 pathway 5, while a mitochondrial microprotein form (NCBP2-AS2) regulates energy metabolism and neurogenesis, with downregulation observed in Alzheimer's disease 6.