Figure 7. U0126 inhibits 5-Fu resistance in CRC through the ERK/MAPK signaling pathway. (A, B) Synergistic effects of U0126 and 5-Fu on DLD-1 5-FuR and HCT116 5-FuR cells. Combo = 5-Fu + U0126. (C, D) Knockdown ERK/MAPK by U0126 blocks TIMP-2 induced 5-Fu resistance in CRC cells. DLD-1 5-FuS and HCT116 5-FuS cells were cultured with 5 μM of U0126 for 24 h and then cultured with recombinant TIMP-2 (10 ng/ml) for 6 h, followed by increasing concentrations of 5-Fu treatment for 3 days. Combo = TIMP-2 + U0126. Combination index (CI) is presented below the bars. Data from triplicate wells of 3 independent experiments. (A, B) *p < 0.05, **p < 0.01 by Student’s t-test between group +5Fu and group Combo. (C, D) *p < 0.05, **p < 0.01, ***p < 0.001 by one-way ANOVA or two-way ANOVA.