PBX2 (PBX homeobox 2) is a transcriptional activator that belongs to the PBX family of homeodomain-containing proteins. PBX2 functions as a DNA-binding transcription factor that binds the sequence 5'-ATCAATCAA-3' and activates transcription of target genes such as PF4 in complex with MEIS1 1. The protein demonstrates cooperative DNA binding with HOX proteins, including HOXB-7 and HOXB-8, and forms heterodimeric and trimeric complexes with cofactors like Pbx2 and Meis1 to determine target gene specificity 21. PBX2 is widely expressed across tissues and cell types, unlike its family member PBX1 3. The gene is located on chromosome 6 within the major histocompatibility complex region 4. In disease contexts, PBX2 has been implicated in cancer progression, where it acts as an upstream transcriptional activator driving oncogenic pathways in head and neck squamous cell carcinoma 5, and cooperates with HOXA6 to promote metastasis in gastric cancer 6. Additionally, PBX2 has been identified as having diagnostic potential in inflammatory conditions like Crohn's disease 7. The protein's activity in chr6 remodeling and epigenetic regulation involves recruitment by factors like ASH1L to regulatory elements 8.