Résumé
Curcumin, the active ingredient of turmeric, has the ability to inhibit the carcinogenic pathways, and thus can prevent or postpone the carcinogenic process in different animal species. Retention time of curcumin is short due to the quick excretion of the body, so, the therapeutic effects of curcumin are restricted resulting in short-term retention in the plasma. Therefore, several methods are used for increasing the efficiency of curcumin in plasma and tissues. The present study is designed to evaluate the effects of the anti-proliferative and anti-carcinogenic of nano-curcumin in rat colon cancer. In this study which was performed in Cancer Research Center of Tehran University of Medical Sciences in 2012. Thirty rats have divided into control, curcumin and nano-curcumin groups. All animals received azoxymethane [15 mg/kg, s.c] as a carcinogen, once a week for two consecutive weeks. Animals received curcumin 0.2% and nano-curcumin 2 weeks before azoxymethane injection up to 14 weeks after the last injection of azoxymethane in curcumin and nano-curcumin groups, respectively. At the end of experiment, the colorectal specimens from all mucosal lesions were obtained for histo-and-immunohistochemical [Ki-67 and COX-2] studies. The cytological and morphological changes of the cells in nano-curcumin group were significantly lower compared to other groups [P<0.05]. In addition, the Ki- 67 and COX-2 proteins expression was lower in the nano-curcumin group in compareson with the curcumin and control groups [P<0.05]. The results indicate that the using a suitable nanoparticle can be appropriately resolved the low bioavailability of curcumin. This can be an important method to use of natural products in the prevention and/or treatment of cancer.