Abstract: In this study,by using MTT assay,EB/AO double staining fluorescence microscopy and FITC/PI double staining flow cytometry,we investigated the combined effects of curcumin and 5-FU on growth,apoptosis and proliferation in human colon cancer cell line SW480.The results showed that curcumin (25 μM),combining with low dose (2.4 μM) and middle dose (4.8 μM) of 5-FU,can effectively inhibit growth,induce apoptosis and arrest cell cycle in S phase of SW480 cells.The combined inhibitory effect of curcumin with low-dose 5-FU group was stronger than that of the middle-dose (4.8 μM) 5-FU group (P<0.05);Similarly,the combination of curcumin with middle-dose 5-FU showed better inhibitory effects when comparing to the high-dose (9.6 mol/L) 5-FU group(P<0.05),suggesting that curcumin can enhance the antitumor effect of 5-FU against SW480 cells,or have the synergic effect to 5-FU.Our study provided a preliminary experimental basis for using curcumin as an adjuvant to 5-FU with the benefit of reducing its toxicity in the clinical treatment of colon cancer.

Key words: curcumin, 5-FU, SW480 cell, growth inhibition, apoptosis, cell cycle