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

Abstract

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. Randomised animal study. 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. Both treatments significantly delayed the onset and development of tumours. However, the combined treatment had the best response (p < 0.01). 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.