Meta-Biol

• Pathways

Beta-1,4 N-acetylgalactosaminyltransferase 2 (B4GALNT2), resident on the Golgi membrane, mediates the formation of the Sda antigen through the addition of an N-acetylgalactosamine (GalNAc) residue via a β1,4-linkage to the sub-terminal galactose residue substituted with an α2,3-linked sialic acid residue (Montiel et al. 2003, Lo Presti et al. 2003). The Sda antigen is a carbohydrate determinant expressed on erythrocytes and secretions of the vast majority of Caucasians and ethnic groups and its expression has an impact on the physiology and the pathology of several biological systems (Dall'Olio et al. 2014). In normal colon, B4GALNT2 levels are high and control the biosynthesis of Sda while at the same time inhibiting the formation of sialyl-Lewis X antigen (sLeX), involved in metastasis (Groux-Degroote et al. 2014).