Curcumin reverses doxorubicin resistance in colon cancer cells at the metabolic level

Abstract

Doxorubicin (Dox) is commonly used for the treatment of malignant tumors, including colon cancer. However, the development of P-glycoprotein (P-gp)-mediated multidrug resistance (MDR) in tumor chemotherapy has seriously reduced the therapeutic efficacy of Dox. Natural product curcumin (Cur) was demonstrated to have a variety of pharmacological effects, such as anti-tumor, anti-oxidation and anti-aging activities. Here, we examined the MDR reversal capability of Cur in drug sensitive-(SW620) and resistant-(SW620/Ad300) colon cancer cells, and elucidated the underlying molecular mechanisms at the metabolic level. It was found that Cur reversed P-gp-mediated resistance in SW620/Ad300 cells by enhancing the Dox-induced cytotoxicity and apoptosis. Further mechanistic studies indicated that Cur inhibited the ATP-dependent transport activity of P-gp, thereby increasing the intra-celluar accumulation of Dox in drug-resistant cells. Metabolomics analysis based on UPLC-MS/MS showed that the MDR phenomenon in SW620/Ad300 cells was closely correlated with the upregulation of spermine and spermidine synthesis and D-glutamine metabolism. Cur significantly inhibited the biosynthesis of spermine and spermidine by decreasing the expression of ornithine decarboxylase (ODC) and suppressed D-glutamine metabolism, which in turn decreased the anti-oxidative stress ability and P-gp transport activity of SW620/Ad300 cells, eventually reversed MDR. These findings indicated the MDR reversal activity and the related mechanism of action of Cur, suggesting that Cur could be a promising MDR reversal agent for cancer treatment.