2015/06/29

The Tn antigen (α-O-GalNAc-Ser/Thr) is one specific human tumor-associated structures

The Tn antigen (α-O-GalNAc-Ser/Thr) is one specific human tumor-associated structures. This molecule is expressed in ca. 90 % of carcinomas, and there is a direct correlation between the aggressiveness of the carcinoma and the occurrence of this antigen. Consequently, the Tn antigen has found widespread use as biomarker and as a potential therapeutic target. MUC1 is a heavily O-glycosylated membrane glycoprotein consisting of tandem repeats of 20 amino acids (AHGVTSAPDTRPAPGSTAPP), with five possible glycosylation sites. This protein is overexpressed and only partially glycosylated with the Tn-antigen in cancer cells. Consequently, peptide epitopes that are masked in healthy cells, are now accessible and can interact with the immune system. A collaborative work including researchers at the University of La Rioja, CSIC, Cambridge, and the Structural Biology Unit of CIC bioGUNE has unraveled the molecular recognition features, at atomic resolution, of the interaction of two Tn-containing MUC1 glycopeptides to one specific anti-MUC1 antibody. This research may have important implications for the design of novel antibodies and biosensors.

More information at http://onlinelibrary.wiley.com/doi/10.1002/anie.201502813/full