HOXC9 is a homeobox transcription factor that functions as a sequence-specific DNA-binding regulator with diverse roles across developmental and pathological contexts. In vascular biology, HOXC9 maintains endothelial cell quiescence by directly repressing interleukin-8 transcription, thereby inhibiting angiogenesis and vascular morphogenesis 12. HOXC9 also regulates adipose tissue development in a depot-specific manner, with higher expression in subcutaneous versus omental adipose tissue, correlating with body fat mass and metabolic parameters 3. In neuroblastoma, HOXC9 links cell-cycle exit to neuronal differentiation by targeting both proliferation and differentiation genes, with high expression associated with improved prognosis and retinoic acid responsiveness 4. Conversely, HOXC9 functions as an oncogene in multiple cancers: it is upregulated in lung adenocarcinoma and glioblastoma stem cells, promoting proliferation, migration, and invasion 56. In gastric cancer, HOXC9 promotes metastasis and stem cell-like phenotype through dysregulation of the miR-26a/HOXC9 axis 7. These findings establish HOXC9 as a context-dependent regulator with therapeutic potential in both cancer immunotherapy and differentiation-based treatments.