MAGE-A4 (E7O1U) XP^® Rabbit mAb (Alexa Fluor^® 647 Conjugate) #20840

Cancer/testis antigens (CTAs) are a family of more than 100 proteins whose normal expression is largely restricted to immune privileged germ cells of the testis, ovary, and trophoblast cells of the placenta. Although most normal somatic tissues are void of CTA expression, due to epigenetic silencing of gene expression, their expression is upregulated in a wide variety of human solid and liquid tumors (1,2). As such, CTAs have garnered much attention as attractive targets for a variety of immunotherapy-based approaches to selectively attack tumors (3).

Melanoma-associated antigen-A4 (MAGE-A4) is a cancer testis antigen that belongs to the type I MAGE family of proteins. MAGE-A4 is often overexpressed and mutated in several types of cancer (4-8). Research shows MAGE-A4 promotes aberrant cell growth by preventing p53-dependent cell cycle arrest and apoptosis in normal oral keratinocytes (9). However, MAGE-A4 was also found to interact with the liver oncoprotein gankyrin, suppressing its tumorigenic activity (10). The diverse roles of MAGE-A4 in tumor development may be dependent upon sub-cellular localization (nuclear or cytosolic) and p53 status (6). Due to its upregulated expression in human tumors and high degree of immunogenicity, MAGE-A4 has received significant attention as an immunotherapy target through the use of vaccines and adoptive cell therapy (11-14).