B3GNT6 encodes a beta-1,3-N-acetylglucosaminyltransferase that plays a crucial role in O-glycan biosynthesis, specifically synthesizing core 3 structures that are important precursors for mucin-type glycoproteins in digestive organs 1. The enzyme demonstrates substrate specificity influenced by flanking charge preferences, being less affected by charge compared to other O-glycosyltransferases like C1GALT1 1. In colorectal cancer, B3GNT6 functions as a tumor suppressor gene, with downregulation associated with poor patient outcomes and reduced overall survival 2. Low B3GNT6 expression correlates with chromosome 11, KRAS mutations, and increased proteasome activity 2. The gene shows simultaneous low expression with other tumor suppressors CLCA1 and UGT2A3, and restoration of these genes through miRNA inhibition can suppress colon cancer cell proliferation and metastasis 3. B3GNT6 expression is also associated with m6A methylation patterns in colorectal cancer and correlates with clinical stage and prognosis 4. Additionally, high B3GNT6 expression in mucinous gastric adenocarcinoma contributes to favorable prognosis 5, and its downregulation drives immature glycosylation phenotypes associated with cancer aggressiveness 6.