Melanoma-associated antigen 12 peptide presented by human leukocyte antigen A*02:01 (MAGE-A12/HLA-A*02:01)

Melanoma-associated antigen 12 (MAGE-A12) peptide presented by human leukocyte antigen A*02:01 (HLA-A*02:01) is a peptide-major histocompatibility complex (pMHC) that serves as a target for cancer immunotherapy. MAGE-A12 is a member of the Cancer-Testis Antigen (CTA) family, which are proteins typically restricted to the testis and placenta but aberrantly expressed in various cancers such as melanoma and lung carcinoma (UniProt P43366). The HLA-A*02:01 molecule presents specific MAGE-A12-derived peptides, such as the KLIANNTRL sequence, to the immune system for recognition by CD8+ T cells. Therapeutic approaches primarily utilize T-cell receptor (TCR) engineered T cells designed to bind this pMHC with high affinity, triggering a cytotoxic immune response against tumor cells. However, clinical trials have revealed significant safety risks, as MAGE-A12 was found to be expressed in healthy human brain tissue, specifically the thalamus. This led to severe neurotoxicity in patients treated with TCRs that recognized MAGE-A12, either as a primary target or through cross-reactivity with MAGE-A3 (Morgan et al., 2013, Journal of Clinical Oncology). Consequently, while it remains a potent tumor-associated target, its clinical application requires extreme caution and precise engineering to avoid off-tumor toxicity.

Other names

MAGEA12-HLA-A*02:01MAGE-A12:170-178/HLA-A2Cancer/testis antigen 1.12

T-cell receptor (TCR) mediated recognition of the peptide-MHC complex on the tumor cell surface, leading to cytotoxic T-lymphocyte activation and tumor cell lysis.