Thus, pre- and postoperative plasma levels of GSH levels and antioxidant enzyme (CAT, GPx, NQO1, and SOD) activities as well as protein and mRNA expressions of related antioxidant enzymes (GCLC, CAT, GPx, and MnSOD) and Nrf2, a well-known transcription factor that regulates expression of detoxifying enzyme genes, in skin lesions were determined in BCC patients compared with control subjects. Here, CAT is linked to skin basal cell carcinoma.