What makes MUC1 a tumor antigen?

The epithelial mucin 1 (MUC1) is an accepted serum tumor marker and cellular tumor antigen. We discuss recent views on the difference(s) between normal and tumor MUC1, and its implication for the development of cancer vaccines and antibody therapies, with special emphasis on the role of glycosylation. Copyright (C) 2005 S. Karger AG, Basel.