ERBB2 and colorectal cancer: As the HER-2/neu-derived peptides, naturally processed as TAA, are recognized by tumour-specific, HLA-A2-restricted CTL in colorectal cancer [21], in the next set of experiments we evaluated the proliferative response of T cells stimulated with HER2/neu369–377 immunodominant peptide in the presence of patients’ BM CD34+ cell-derived monocytes as APC.