HOXD9 is a sequence-specific transcription factor that plays critical roles in development and cancer progression. As a member of the homeobox gene family, HOXD9 provides cells with positional identity along the anterior-posterior axis during embryonic development and regulates transcription through RNA polymerase II-mediated mechanisms 1. In cancer contexts, HOXD9 functions as an oncogene across multiple malignancies. In gliomas, HOXD9 is highly expressed in tumor tissues and glioma cancer stem cells, where it promotes cell proliferation and survival 23. HOXD9 drives epithelial-mesenchymal transition (EMT) and metastasis through various pathways: it transcriptionally represses PAXIP1-AS1 in gastric cancer, leading to enhanced invasion via the PABPC1/PAK1 axis 1, and regulates miR-451a/PSMB8 signaling through PI3K/AKT pathways in anaplastic thyroid carcinoma 4. In cervical cancer, HOXD9 promotes metastasis by transcriptionally activating HMCN1 5. Additionally, HOXD9 contributes to diabetic kidney disease progression by promoting macrophage M1 polarization through the NF-κB pathway via APOC1 regulation 6. HOXD9 serves as a potential prognostic biomarker, with high expression correlating with poor outcomes and altered immune microenvironments in various cancers 7.