UGT8 catalyzes the transfer of galactose to ceramide, a critical step in galactocerebroside biosynthesis, which are major sphingolipids of the myelin membrane in the central and peripheral nervous systems. The enzyme also synthesizes monogalactosyl diacylglycerols and sulfatides, lipid classes involved in membrane organization and cellular signaling. Beyond its canonical myelin function, UGT8 has emerged as a metabolic regulator in cancer. In non-small cell lung cancer (NSCLC), SOX9-mediated UGT8 upregulation promotes glycolysis and maintains malignancy 1. In basal-like breast cancer, UGT8 expression activates integrin αVβ5 signaling via the sulfatide biosynthetic pathway, driving tumorigenicity and metastasis 2. Similarly, in intraductal papillary mucinous neoplasm-associated pancreatic cancer, UGT8 inhibition reduces sulfatide levels and suppresses tumor growth through ceramide-mediated mitophagy and apoptosis 3. In colorectal cancer, UGT8-mediated sulfatide synthesis controls BAX mitochondrial localization and apoptosis sensitivity 4. In aging, kidney UGT8 expression correlates with sex-specific glycolipid biosynthesis and inflammatory responses 5. Recent evidence also suggests UGT8 regulates membrane lipid saturation signaling through MGDG production 6. Clinically, zoledronic acid, an FDA-approved osteoporosis drug, directly inhibits UGT8 and shows promise in basal-like breast cancer 2. A genome-wide association study identified UGT8-region variants associated with postpartum depression risk in Japanese women 7.