Anti-cancer and Anti-angiogenic Effects of Curcumin and Epigallocathechin-3-Gallate in a Mouse Model of Renal Cancer

Although conventional chemotherapeutic drugs are the first line of treatment for cancer, they have numerous side effects. One of the emerging challenges in cancer treatment is drug resistance. Nat-ural compounds have proven effective against various hallmarks of cancer for their multi-target inhibition properties, but especially for their ability to synergistically bypass low bioavailability. Methods: The present study investigated the in vivo antitumor effects of a combination of two natural dietary agents, epigallocatechin-3-gallate (EGCG) from Camelia Sinensis and curcumin, a component of turmeric (Curcuma longa). We aimed to compare, for the first time in vivo, the antiangiogenic and antitumor effects of sunitinib with the combination of curcumin and EGCG in a mouse model of renal cell carcinoma (ccRCC). It was shown that they are able to inhibit cell survival, proliferation of several type of cancer, including renal cell carcinoma (ccRCC), by mod-ulating different signaling pathways and that their combination respect to single compound syn-ergistically decreased angiogenesis. Results: Herein, we highlighted that these compounds inhib-ited the growth of xenografted renal cancer in nude mice by significant inhibition of tumor vol-ume, tumor weight and CD31 expression with no signs of hepatic toxicity. Moreover, mice treated with these natural compounds showed a significant reduction in angiogenesis and an improve-ment in survival rate with p<0.05. Finally, pretreatment of mice with a diet containing 0.6% curcumin before injection of tumor cells showed a significant inhibition of tumor engraftment in 60% of mice with respect to controls and other groups. Conclusions: Taken together, our data in-dicate, for the first time, that the combination of curcumin and EGCG acts in a synergistic manner to inhibit the growth and angiogenesis of ccRCC and with less toxicity than sunitinib and provide an important rationale for future clinical development for chemoprevention and treatment of re-nal cancer.