The human MAGE-1, MAGE-3 and MART-1 genes code for antigens that are specifically recognized by cytolytic T lymphocytes in a MHC-restricted manner. The MAGE-1 and MAGE-3 genes are expressed in tumors of different histotypes but not in normal adult tissues (with the exception of testis), while the MART-1 gene appears to be selectively expressed in melanoma. MAGE-1, MAGE-3 and MART-1 antigens may therefore constitute useful targets for specific anti-tumor immunization of cancer patients. Here we have investigated the expression of MAGE-1, MAGE-3 and MART-1 in 11 neuroblastoma (NB) cell lines and 73 NB tumor masses. MAGE-1 and MAGE-3 transcripts were detected simultaneously in 36% of the cell lines and in 16% of tumor samples. The MAGE-1 gene was never expressed alone except in one tumor. In contrast, MAGE-3 mRNA was found in approximately 40% of the NB tumor samples in the absence of MAGE-1 mRNA. No expression of the MART-1 gene was observed in any cell line or tumor sample. No correlation was found between MAGE gene expression and clinical stage, event-free survival and presence or absence of N-myc amplification.