Clinically, sialic acid-rich glycoconjugates serve as established biomarkers (CA19-9/SLex in pancreatic cancer; CA125/MUC16 in ovarian cancer; CA15-3/MUC1 in breast cancer) [138], while specific sialyltransferases show prognostic potential. The gene discussed is MUC16; the disease is ovarian carcinoma.