Topical effect of piroxicam gel and calendula ointment on 7,12 Dimethylbenz(a)anthracene Anthracene and croton oil -induced skin cancer in mice

Abstract

Introduction: Cancer incidence is one of the human problems and in order to understand its mechanistic aspects several studies have been performed. Also, there are conflicting reports on the effect of piroxicam on cancer. Objective: Topical effect of piroxicam gel and calendula ointment on imethylbenz(a)anthracene and croton oil induced skin cancer in mice.Materials and methods: Sixty female Albino Swiss mice were divided into 3 groups of 20 in each group. The back of the mice were shaved. After 24 hours, the animals of group 1 received Placebo gel as control and groups 2 and 3 piroxicam0/5% gel and calendula ointment 2% once daily for 15 days respectively. Nine hours after application of the final dose, the mice of all groups were initiated by a single dose of DMBA (60g/100l acetone/mouse). After 7 days, animals were promoted topically by croton oil (1mg/200l acetone/mouse) twice weekly for period of 28 weeks.Results: At the end of the 10th week the first tumors were observed in the group of animals receiving piroxicam plus DMBA and promoted with croton oil. However, calendula receiving animals, the tumors occurred at week 13th in the control group (plscebo+DMBA+Croton oil) and calendula receiving animals, the tumors occurred at week 13th.Also, both in number and percentage of tumor incidence significantly were higher in the group receiving piroxicam at various intervals of times. Discussion: The results obtained from this study showed that piroxicam could exacerbate skin tumors in comparison to the control group. Overall, our study demonstrates that piroxicam is responsible for mouse skin carcinogenesis. The role of piroxicam in mice skin cancer induction may be due to its potential capabilities of producing oxidative stress injuries and DNA damage. So, Piroxicam has the ability to increase tumor incidence in comparison to the control group and it seems that high dose of piroxicam probably is a major cause of carcinogenesis.