B4GALNT1 and neoplasm: Alterations in protein O-glycosylation by a family of over 20 polypeptide GalNAc-transferases (GalNAcTs or GALNTs) catalyzing the transfer of N-acetylgalactosamine (GalNAc) from UDP-GalNAc to the hydroxyl group of a serine or threonine residue have been linked with a wide variety of epithelial developmental defects and neoplasms [4-6, 8-10].