Perspectives for immunization of HLA-A1 patients carrying a malignant melanoma expressing gene MAGE-1.

Many human melanoma tumors express antigens that are recognized in vitro by cytolytic T lymphocytes derived from the tumor-bearing patient. A gene has been identified that directs the expression of antigen MZ2-E on a human melanoma cell line. This gene, which has been named MAGE-1, shows no similarity to known sequences and belongs to a family of at least 3 closely related genes. Gene MAGE-1 is expressed in approximately 40% of melanoma tumor samples and by some tumors of other histological types. No expression has been observed in a panel of normal tissues. Antigen MZ2-E appears to be presented by HLA-A1, a HLA type found in approximately 25% of the population. Thus, precisely targeted experimental immunotherapy directed against antigen MZ2-E could be provided to individuals identified as HLA-A1 and MAGE-1 positive by HLA typing and analysis of the RNA of a small tumor sample.