EXPRESSION OF MAGE GENES IN PRIMARY AND METASTATIC CUTANEOUS MELANOMA

Human genes MAGE-1 and MAGE-3 code for antigens that are recognized on melanoma cells by autologous cytolytic T lymphocytes. These antigens may constitute useful targets for specific anti-tumor immunization of cancer patients, since genes MAGE-1 and MAGE-3 are expressed in a numb er of tumors of different histological types, but are not expressed in normal adult tissues other than testis. This also applies to genes MA GE-2 and MAGE-4, which are closely related to MAGE-1 and MAGE-3. We ha ve analyzed the expression of these 4 MAGE genes in cutaneous melanoma . Sixteen of 100 primary tumors vs. 69 (48%) of 145 metastases from in dividual patients expressed MAGE-1. Similar differences in the frequen cy of gene expression between primary and metastatic tumor samples wer e observed for MAGE-2, MAGE-3, and MAGE-4. MAGE expression in primary tumors was correlated with tumor thickness: there was a significantly increased frequency in the expression of MAGE-1, -2 and -3 in tumors o f greater thickness. Benign and dysplastic nevi, as well as in site me lanomas, did not express any of the 4 MAGE genes. (C) 1995 Wiley-Liss, Inc.