Topical chemoprevention of skin cancer in mice, using combined inhibitors of 5-lipoxygenase and cyclo-oxygenase-2

Abstract

Objective: Skin cancer is the most common cancer, and often occurs in the head and neck region. This study aimed to investigate whether a combination of inhibitors of cyclo-oxygenase-2 and 5-lipoxygenase, applied via a microemulsion delivery system, would be effective in topically inhibiting skin carcinogenesis.Study design: Randomised animal study.Methods: Twenty-four nude mice were intradermally inoculated with carcinoma cells and then divided into three groups (eight animals each): group one received no treatment; group two received celecoxib alone; and group three received a combination of zileuton and celecoxib. Tumour incidence and growth were measured for 14 days.Results: Both treatments significantly delayed the onset and development of tumours. However, the combined treatment had the best response (p < 0.01).Conclusion: The results clearly showed that topical treatment with either celecoxib alone or celecoxib plus zileuton significantly inhibited skin carcinogenesis, and that a combination of both agents had the best results.