MAGEA1 (MAGE family member A1) is a cancer-testis antigen that functions as a transcriptional regulator with tumor suppressor-like properties. The protein interacts with FBXW7 to promote ubiquitin-mediated degradation of NICD1, thereby inhibiting Notch signaling and suppressing cell proliferation and migration in breast and ovarian cancer cells 1. MAGEA1 also forms a complex with CTCF and DNMT3a to increase promoter methylation and repress BORIS expression, leading to cancer cell death 2. Expression of MAGEA1 is primarily controlled by DNA methylation, with promoter hypomethylation in tumors leading to increased histone H3 acetylation and gene activation 3. Clinically, MAGEA1 serves as an important immunotherapy target, with treatment-expanded tumor T cell clones recognizing MAGEA1 as a cancer-specific antigen in oral cancer patients receiving checkpoint blockade therapy 4. The first-in-human trial of IMA202, an anti-MAGEA1 TCR-transgenic T cell therapy, demonstrated manageable safety profiles with 68.8% of patients achieving stable disease in advanced solid tumors 5. MAGEA1 expression is observed in 15% of synovial sarcomas and may serve as both a therapeutic target and prognostic marker 6.