MAGE, BAGE and GAGE gene expression in human rhabdomyosarcomas

MAGE, BAGE and GAGE genes encode tumor-associated antigens that are present ed by HLA class I molecules and recognized by CD8(+) cytolytic T lymphocyte s. These antigens are currently regarded as promising targets for active, s pecific tumor immunotherapy because MAGE, BAGE and GAGE genes are expressed in many human cancers of different histotype and are silent in normal tiss ues, with the exception of spermatogonia and placental cells. MAGE, BAGE an d GAGE gene expression has been extensively studied in different tumors of adults but is largely unknown in many forms of pediatric solid cancer. Usin g RT-PCR, we analyzed MACE-1, MAGE-2, MAGE-3, MAGE-4, MAGE-6, BAGE, GAGE-1, -2 or -8 and CAGE-3,-4,-5,-6 or -7b gene expression in 31 samples of pediat ric rhabdomyosarcoma, the most frequent form of malignant soft tissue tumor in children. MAGE genes were expressed in a substantial proportion of pati ents (MAGE-1, 38%; MAGE-2, 51%; MAGE-3, 35%; MAGE-4, 22%; MAGE-6 35%), whil e expression of BAGE (6%); GAGE-1, GAGE-2 and GAGE-1 (9%); and GAGE-3, GAGE -4, GAGE-5, GAGE-6 and GAGE-7B (16%) was less frequent. Overall, 58% of tum ors expressed at least 1 gene, and 35% expressed 3 or more genes simultaneo usly. Our data suggest that a subset of rhabdomyosarcoma patients could be eligible for active, specific immunotherapy directed against MAGE, BAGE and GAGE antigens. (C) 2001 Wiley-Liss, Inc.