HOXA3 is a sequence-specific transcription factor that specifies anterior-posterior positional identity during development 1. During embryogenesis, HOXA3 is essential for pharyngeal arch patterning and third pharyngeal pouch derivatives (thymus and parathyroids), functioning in both neural crest cells and endoderm with tissue-specific roles in morphogenesis, differentiation, and cell survival 12. In adults, HOXA3 promotes angiogenesis and wound repair by inducing endothelial and epithelial cell migration through upregulation of MMP-14 and uPAR, and HOXA3 gene transfer improves wound healing in diabetic mice 3. In cancer contexts, HOXA3 is aberrantly expressed in multiple tumor types and promotes disease progression through distinct mechanisms. In glioblastoma, HOXA3 cooperates with the histone demethylase KDM6A to activate aerobic glycolysis genes (HK2, PKM2) via H3K27 demethylation, accelerating proliferation and tumor growth 4. In renal cell carcinoma, HOXA3 transcriptionally activates USP15, which suppresses autophagy and promotes M2-type macrophage polarization through SQSTM1 deubiquitination and CCL2 secretion 5. HOXA3 is hypermethylated across 16 cancer types, with 3' UTR hypermethylation in oral squamous cell carcinoma associated with poor survival 67. These findings establish HOXA3 as a critical developmental regulator with multifaceted roles in tumor progression.