ST6GAL2 encodes a sialyltransferase enzyme that catalyzes the transfer of sialic acid from CMP-sialic acid to galactose-containing oligosaccharides, specifically targeting Gal-β-1,4-GlcNAc sequences at non-reducing ends 1. The enzyme exhibits tissue-specific expression, being predominantly expressed in embryonic and adult brain tissues, unlike the ubiquitously expressed ST6GAL1 1. ST6GAL2 transcription is regulated by neuronal-specific factors including Sox5, Puralpha, and Olf1 as activators, while NF-κB and NRSF act as repressors 1. In the adult mouse brain, ST6GAL2 produces primarily α2,6-sialylated O-glycans rather than N-glycans, with disialyl-T antigen and sialyl-(6)T antigen being the major products 2. The enzyme plays significant roles in cancer biology, with elevated ST6GAL2 expression associated with tumor progression in breast cancer and follicular thyroid carcinoma 34. ST6GAL2 promotes cell adhesion, invasion, and metastatic pathways through regulation of molecules like ICAM-1, VCAM-1, and matrix metalloproteinases 3. Additionally, ST6GAL2 participates in immune responses during bacterial infections, contributing to MAPK-mediated inflammatory signaling in intestinal epithelial cells 5.