SHARED T-CELL EPITOPES IN EPITHELIAL TUMORS

we have previously shown the importance of human leukocyte antigen (HLA)-A2 and the proto-oncogene HER2/neu in the T cell recognition of ovarian cancer, Since these proteins are ubiquitously expressed in epithelial-derived tumors, we have acid-eluted HLA-bound peptides from ovarian cancers, fractionated the peptides, and reconstituted T cell epitopes on the HLA-A2(+) T2 cell line to determine if common tumor-associated antigens exist among HLA-A2(+), HER2/neu(+) epithelial cancers. We demonstrate that tumor-specific cytotoxic T lymphocytes (CTL) generated from tumorinfiltrating lymphocytes isolated from three ovarian, two breast, and two non-small-cell lung cancers recognize at least three of the same peptide fractions from multiple elutions, One of these peptide fractions coelutes with a HERS/neu-derived peptide which has been shown recently to be recognized by these same CTL, These findings demonstrate that a common peptide-based tumor vaccine is theoretically possible for many different epithelial-derived cancers. (C) 1995 Academic Press, Inc.