Structure, chromosomal localization, and expression of 12 genes of the MAGE family

Abstract

We reported previously that human gene MAGE-1 directs the expression of a tumor antigen recognized on a melanoma by autologous cytolytic T lymphocytes. Probing cosmid libraries with a MAGE-1 sequence, we identified 11 closely related genes. The analysis of hamster-human somatic cell hybrids indicated that the 12 MAGE genes are located in the q terminal region of chromosome X. Like MAGE-1, the 11 additional MAGE genes have their entire coding sequence located in the last exon, which shows 64%-85% identity with that of MAGE-1. The coding sequences of the MAGE genes predict the same main structural features for all MAGE proteins. In contrast, the promoters and first exons of the 12 MAGE genes show considerable variability, suggesting that the existence of this gene family enables the same function to be expressed under different transcriptional controls. The expression of each MAGE gene was evaluated by reverse transcription and polymerase chain reaction amplification. Six genes of the MAGE family including MAGE-1 were found to be expressed at a high level in a number of tumors of various histological types. None was expressed in a large panel of healthy tissues, with the exception of testis and placenta.

MAGE-A8 overexpression in transitional cell carcinoma of the bladder: identification of two tumour-associated antigen peptides

“…As was previously described, 46% of hepatocellular carcinomas (Tahara et al, 1999) and 44% of colorectal carcinomas (Hasegawa et al, 1998) expressed the MAGE-A8 gene. Moreover, expression of MAGE-A8 gene in adult tissue is limited to the male germ line, which does not express HLA molecules, and to the placenta (De Plaen et al, 1994).…”

“…The first member of the MAGE family was identified as a gene encoding for tumour-specific antigen (van der Bruggen et al, 1991). A cluster of 12 MAGE genes was later recognised, designated MAGE-A 1 -12, it was mapped to the q28 arm of the X chromosome (De Plaen et al, 1994). Two more clusters were later identified, MAGE-B and MAGE-C, all the genes in the three subfamilies are characterised by a long-terminal exon, encoding the entire protein, and their expression is restricted to tumours.…”

“…MAGE-A8 expression in normal tissues is limited to the testis and the placenta (De Plaen et al, 1994). Its expression was examined in 80 pairs of normal colon and colorectal carcinomas, the MAGE-A8 gene was expressed in 44% of the tumour samples, and not expressed in any of the 80 normal tissue (Hasegawa et al, 1998).…”

The SSX gene family: Characterization of 9 complete genes

“…Four complete genes, SSX6, 7, 8 and 9, as well as 10 pseudogenes or gene fragments, were identified. Similar to the MAGE family, 14 and most other CT antigen genes, 15 all SSX genes, except for a single pseudogene on chromosome 6, are located on chromosome X.…”

Induction of antibody response to human tumor antigens by gene therapy using a fusigenic viral liposome vaccine

“…There are other MAGE gene digested with restriction enzyme and the appropriate size family members with similar homologies. 25 The strategy fragment was subcloned into the vector pET30b of using two dominant immunogenic MAGE family anti-(Novagen, Madison, WI, USA) with hexaHis on the Cgens may be beneficial in that they can elicit immunity terminus, resulting in a plasmid designated pSH007. The to a wide spectrum of MAGE antigens expressed by diffull length MAGE-3 cDNA was sequenced by dideoxynuferent human tumors.…”