Synergistic anticancer effects of curcumin and crocin on human colorectal cancer cells

Background Curcumin, a polyphenol compound derived from the Curcuma longa L, and crocin, a hydrophilic carotenoid from Crocus Sativus Linnaeus, are traditionally used in food preparations in many countries and could act as chemopreventive compounds against several diseases, including cancer. In this study, the synergistic effect of curcumin and crocin was investigated for the first time on inducing apoptosis and suppressing colorectal cancer cells (SW-480 cell line). Methods and Results MTT, Annexin V-FITC/PI, and DAPI staining tests were employed to evaluate cell viability and apoptosis induction, respectively. The combined effect of curcumin and crocin on the expression of genes involved in apoptosis and proliferation was quantified using real-time PCR. The combination therapy effect on cell cycle progression was also evaluated by flow cytometry. Based on the obtained results, curcumin and crocin treatment could cooperatively reduce cell viability and induce apoptosis in SW-480 cells by modulating the expression of Bax, Bcl-2, Caspase-3, Caspase-8, Caspase-9, Jak2, Stat3, and Akt1 genes. Besides, curcumin and crocin were able to synergistically increase the cell cycle arrest at the sub G1 phase, induce autophagy and decrease the clonogenic ability of SW-480 cells. Conclusions These results suggested that curcumin and crocin combination could be considered a more effective therapeutic strategy for inhibiting colorectal cancer.