GAGE1 (G antigen 1) is a cancer-testis antigen encoded by a germ line-associated gene normally expressed in testicular spermatogonia but aberrantly re-expressed in various human malignancies 1. The protein functions as a tumor-associated antigen presented by HLA class I molecules and recognized by CD8+ cytolytic T lymphocytes 2, making it an ideal immunotherapy target due to its cancer-specific expression pattern with minimal expression in normal differentiated tissues 2. GAGE1 is frequently expressed across multiple cancer types. In head and neck squamous cell carcinoma (HNSCC), GAGE1 is expressed in 48.3% of samples and serves as an independent prognostic factor for overall survival; its expression correlates with lymph node metastasis and advanced clinical stage 3. GAGE1 expression has been documented in hepatocellular carcinoma cell lines 4, pancreatic cancer (47% of cell lines) 5, rhabdomyosarcoma (9%) 2, and testicular seminomas (10%) 1. In non-small cell lung cancer, GAGE1 is regulated by the circ_0016760/miR-1287 axis and promotes cell growth and metastasis 6. Clinically, GAGE1 expression is silenced in normal tissues through promoter methylation and can be reactivated by demethylating agents, potentially expanding immunotherapy candidate populations 5. Its tumor-specific expression pattern and immunogenic properties position GAGE1 as a promising biomarker for cancer prognosis and a molecular target for active immunotherapeutic approaches across multiple malignancies.