MUC1 and neoplasm: Third, MUC1 is an interesting tumor-specific epitope; the epitope with the sequence GVTSAPDTRPAPGSTAPPAH was found repeated 20 to 150 times in the extracellular domain of the transmembrane glycoprotein Mucin1 (MUC1) and constitutes the so-called “variable number of tandem repeats region (VNTR)” [43].