Analysis of the peak area of each peptide’s signal showed some candidate autoantigens to be increased and others decreased in melanoma compared to HV sera: 11 significantly increased (TUBB, TUBB1, TUBB2A, TUBB4A, TUBB4B, H4C1, CYP17A1, YWHAZ, MASP1, DLST, PF4, AMBP) and 14 significantly decreased (CP, PLG, GSN, CLU, AHSG, ORM1, ORM2, KNG1, SERPINA1, HRG, HPX, ITIH4, HPR, HP) in patients. The gene discussed is PLG; the disease is melanoma.