Chemopreventive effects of wild carrot oil against 7,12-dimethyl benz(a)anthracene-induced squamous cell carcinoma in mice

Abstract

Context: Daucus carota L. ssp. carota (Apiacea) is widely distributed throughout the world and has many uses in traditional medicine. Objective: The present study investigates the chemopreventive effects of oil extract of D. carota umbels on 7,12-dimethyl benz(a)anthracene (DMBA)-induced skin cancer in mice. Materials and methods: D. carota oil extract (DCOE) was prepared by extracting the dried umbels with 50:50 acetone:methanol. Skin papilloma were initiated by DMBA and promoted by 12-O-tetradecanoyl phorobol-13-acetate (TPA). The extract was administered to animals via gavage (0.02 mL of 100percent oil), intraperitoneal (0.3 mL of 2percent oil), and topical (0.2 mL of 5, 50, and 100percent oil) routes for 20 weeks. Tumor appearance, incidence, yield, and volume were compared with those of a non-treated control group. Results: Topical 100percent treatment delayed tumor appearance, and inhibited tumor incidence and yield by 40 and 89percent, respectively. Topical 50percent treatment inhibited tumor incidence and yield by 30 and 83percent, respectively, whereas the 5percent treatment inhibited tumor yield by 36percent. Tumor volume was decreased by 99, 91, and 70percent following topical treatments with 100, 50, and 5percent oil, respectively. Intraperitoneal treatment inhibited tumor yield by 43percent, and decreased tumor volume by 85percent, whereas gavage treatment showed minimal effects on both. Intraperitoneal and topical treatment decreased infiltration and hyperplasia with an increase in the level of hyperkeratosis. Conclusion: These findings demonstrate that DCOE has remarkable antitumor activity against DMBA-induced skin cancer compared with non-treated animals paving the ground for further investigations. © 2011 Informa Healthcare USA, Inc.