However, cytotoxic T lymphocytes play a key role, targeting melanoma-associated antigens (MAGE—melanoma-associated antigen, BAGE—B melanoma antigen, GAGE—cancer/testis antigen, PRAME—preferentially expressed antigen of melanoma, and NY-ESO-1—New York esophageal squamous cell carcinoma), melanocyte differentiation markers (tyrosinase, Melan-A/MART1, gp100, and TRP-1, TRP-2—tyrosinase-related protein 1 or 2), and mutated or aberrantly expressed antigens (MUM-1—melanoma-associated antigen 1, CDK4, β-catenin, gp100-in4, p15, and N-acetylglucosaminyl transferase V). The gene discussed is CDK4; the disease is melanoma.