MLANA (melan-A/MART-1) is a melanocyte-lineage protein that plays a critical role in melanosome biogenesis and serves as an important melanoma diagnostic and therapeutic target. MLANA is transcriptionally regulated by MITF, a master transcription factor essential for melanocyte development 1. The protein functions in melanosome assembly, likely through stabilization of GPR143 and regulation of PMEL processing, contributing to stage II melanosome formation. MLANA contains conserved HLA-A2-restricted T cell epitopes recognized by melanoma-reactive cytotoxic T lymphocytes (CTLs) derived from tumor-infiltrating lymphocytes 2. These epitopes have intermediate HLA-A2 binding affinity and are efficiently presented to induce melanoma-reactive immune responses. Clinically, MLANA serves as a diagnostic marker in melanoma via the melan-A antibody (HMB-45), and its expression correlates with MITF levels across melanoma cell lines and primary tumors 1. Beyond melanoma, MLANA has emerged as a plasma biomarker in head and neck squamous cell carcinoma (HNSCC), where elevated plasma levels predict tumor progression and independent prognostic significance for progression-free survival in patients receiving chemoradiation therapy 3. MLANA's role in adaptive cell transfer immunotherapy and its tumor-associated expression position it as both a diagnostic tool and potential immunotherapeutic target.