TF and cancer: Abnormal O-glycosylation, especially in mucin and mucin type glyproteins, results in exposure of the peptide core, as well as in the exposure of the normally cryptic core TF (Galβ1-3GalNAcα1-O-Ser/Thr) antigen[9], which is distributed discontinuously along the peptide backbone, and premature sialylation can occur leading to formation of antigens related to cancer progression[10].