MUC5AC and cancer: C1GalT1 is a pivotal glycosyltransferase involved in the biosynthesis of O-linked mucin-type glycans on glycoproteins[2], and there is mounting evidence suggesting that C1GalT1 is upregulated in a variety of epithelial-origin cancers, including breast, colon, esophageal, gastric, head and neck, hepatocellular, pancreatic, and prostate cancers[20].