Chemomodulatory efficacy of lycopene on antioxidant enzymes and carcinogen-induced cutaneum carcinoma in mice

Oxidative stress has been implicated in various pathological processes, including skin tumourigenesis. Cutaneum carcinoma is commonly responsible for considerable morbidity and mortality, and treatments have not progressed substantially in recent years. Alternative strategies, such as chemoprevention, are being considered. In this study, we investigated the chemomodulatory potential of lycopene against 9,10-dimethylbenz[a]anthracene (DMBA)/12-O-tetradecanoylphorbol-13-acetate (TPA)-induced oxidative stress and skin carcinogenesis in female ICR mice. Pretreatment with lycopene at various doses significantly delayed tumour formation and growth. These treatments markedly reduced the tumour incidence and tumour volume. Moreover, lycopene inhibited the formation of reactive oxygen species and malondialdehyde, prevented the loss of glutathione, and affected the activities of a battery of oxidant enzymes in the skin of mice. Furthermore, mice that were administered lycopene exhibited higher levels of translocation of nuclear-factor-erythroid-2-related factor 2 into the nucleus compared with the vehicle-treated and model mice. Collectively, these results indicated that lycopene exerts a protective effect against DMBA/TPA-induced cutaneum carcinoma through antioxidant defence.