부산대학교 도서관

Lifelong sunlight exposure is a major environmental factor for inducing skin cancers. Photo-carcinogenesis is partly due to the UV-mediated impairment of the antioxidant system in the skin, and therefore enzymatic antioxidants, whose activaties or expression levels were decreased, are commonly used experimental biomarkers for skin cancers. This study was aimed at evaluating the availability of inflammatory markers of cyclooxygenase-2 (COX-2) and matrix metalloproteinases-2 and -9 (MMPs 2/9) in comparison with checking the expression levels of antioxidants in cutaneous squamous cell carcinoma (SCC). With the animal model for cutaneous SCC, which was induced by chronic UVB irradiation (3 times/week x 32 weeks) in SKH-1 mice, the levels of markers for inflammation and antioxidants were tested. In Western immunblots and RT-PCR experiments, mRNA and protein levels of COX-2 and MMPs 2/9 were up-regulated with the higher sensitivity for MMP-9 in UVB-induced SCC. Gelatinase activities of MMPs 2/9 were also increased in UVB-induced SCC. As for antioxidants, superoxide dismutase and catalase activities did not change significantly, but glutanione peroxidase, thiredoxin, and peroxiredoxin I were rather up-regulated, in UVB-induced SCC. Consistently, inflammatory markers of COX-2 and MMPs 2/9 were up-regulated with the higher sensitivity for MMP-9 in cutaneous SCC in human. In conclusion, COX-2 and MMPs 2/9 are recommended as useful biomarkers rather than antioxidants for cutaneous SCC. The inflammatory markers along with the animal model for UVB-induced SCC can be a good evaluation system to test chemopreventive or anticancer agents.