RAAG12 carbohydrate antigen (RAAG12) (RAAG12)

RAAG12 is a primate-restricted, N-linked carbohydrate antigen (glycotope) that is highly expressed on the surface of various human adenocarcinomas, particularly those of the gastrointestinal tract, including colon, gastric, and pancreatic cancers (3.1.1, 3.3.2). It consists of a specific sugar structure, identified as containing the Galβ1-3GlcNAcβ1-3Gal epitope, which is found on multiple membrane-associated glycoproteins and receptors such as IGF-IR, EGFR, and EphA2 (3.1.1, 3.2.1). In malignant cells, RAAG12 is distributed across the entire cell membrane, whereas in normal polarized epithelial tissues, its expression is largely restricted to the apical surface or cytoplasm, potentially providing a therapeutic window (3.3.4). The antigen is the target of the chimeric monoclonal antibody RAV12, which has demonstrated potent anti-tumor activity through the induction of oncotic cell death (oncosis), as well as through antibody-dependent cellular cytotoxicity (ADCC) and complement-dependent cytotoxicity (CDC) (3.3.2, 3.3.5). Additionally, binding of antibodies to RAAG12 can modulate growth factor-mediated signaling pathways, such as the IGF-IR pathway, further contributing to its anti-proliferative effects (3.1.1). Clinical development of RAAG12-targeted therapies has explored its potential in treating refractory adenocarcinomas, although challenges regarding dose-limiting toxicities related to normal tissue expression have been noted in early-phase trials (3.3.1, 3.3.4).

Other names

RAAG12 glycotopeRAV12-defined antigenN-linked carbohydrate antigen RAAG12

Induction of oncotic cell death (oncosis), antibody-dependent cellular cytotoxicity (ADCC), complement-dependent cytotoxicity (CDC), and modulation of growth factor signaling (e.g., IGF-IR, EGFR).