Chemopreventive potential of the pentane-based fraction of wild carrot oil against chemically-induced squamous cell carcinoma

Abstract

Daucus carota L. ssp. carota (wild carrot) was recently shown to exhibit in vitro and in vivo anticancer activities [1, 2]. DCOE was chromatographed to yield F1 (pentane; 100%), F2 (pentane-diethyl ether; 50:50), F3 (diethyl ether; 100%) and F4 (chloroform-methanol; 93:7) fractions. The fractions were tested in vitro against several cancer cell lines and F1 was found to possess the highest activity. Therefore, the present study aimed to evaluate its activity using the DMBA/TPA skin carcinogenesis model in mice. Skin papilloma were initiated by DMBA and promoted by TPA. F2 was administered to three experimental groups (10 mg/kg, 50 mg/kg, 200 mg/kg) via intraperitoneal injections thirty min prior to TPA promotion for a period of 21 weeks. Papilloma incidence, yield, and volume were compared with those of a non-treated control group. Treatment with F2 caused an inhibition in papilloma incidence, being highest (50%) at a dose of 200 mg/kg at the end of the experiment (week 21). Also, there was a dose-dependent decrease in papilloma yield during the study period. Additionally, F2 treatment with the three doses significantly decreased the papilloma volume at weeks 15, 18 and 21 (p < 0.05, p < 0.01 and p < 0.01, respectively). In conclusion, these findings clearly demonstrate that F2 has a remarkable antitumor activity against DMBA-TPA induced skin cancer and suggest the need for further studies to isolate the active chemotherapeutic agent.