Identification of epidermal growth factor receptor-derived peptides recognised by both cellular and humoral immune responses in HLA-A24+ non-small cell lung cancer patients.

The epidermal growth factor receptor (EGFR) is one of the most appropriate target molecules for cancer therapy because of its high expression in epithelial cancers. A novel EGFR-tyrosine-kinase inhibitor, ZD1839, has been approved as a drug for non-small cell lung cancer (NSCLC), and many other agents are now being tested in clinical trials. Cytotoxic T lymphocyte (CTL)-directed epitope peptides could be another class of useful compounds in EGFR-targeted therapies. However, at present, there are no data on CTL-directed peptides of EGFR. Therefore, this study aimed to identify immunogenic EGFR-derived peptides in HLA-A24(+) NSCLC patients. We report in this study three such EGFR-derived peptides at positions 54-62, 124-132 and 800-809. These peptides were recognised by both cellular and humoral immune responses in most of the peripheral blood mononuclear cells (PBMCs) and sera from NSCLC patients that we tested. These results may provide a scientific basis for the development of EGFR-based immunotherapy.