Combination effect of Fumos with other agents. Cells were treated with various concentration of (A) 5-FU and a (B) CI/fractional effect curve was calculated using CalcuSyn software in HeLa cells. Cells were treated with various concentrations of (C) SB203580 alone or in combination with Fumos and a (D) CI/fractional effect curve was calculated using CalcuSyn software in HeLa cells. Values are presented as the mean ± standard error of the mean of three experiments. **P<0.01 and *P<0.05. One-way analysis of variance followed by Tukey's test was performed. CI values >1 represents an antagonistic effect, CI=1 represents an additive effect, CI <1 represents a synergistic effect. The combination effect was assessed with each concentration of 5-FU (30, 60 and 120 µg/ml) and SB203580 (12.5, 25 and 50 µg/ml) and the corresponding three concentrations of Fumos (5, 10 and 15 µg/ml). CI, combination index; 5-FU, 5-fluoracil.