MGMT and neoplasm: Because tumor development is often accompanied with the overexpression of tumor‐associated antigens (TAAs) which may elicit immune responses resulting in the production of anti‐TAA autoantibodies, even when antigen expression is minimal, serum autoantibodies can be detected.27 Our present study also showed MGMT autoantibody and its protein expression exhibited a significant correlation (Spearman's r = 0.553, P < 0.001).