In vivo response of HCT-116 xenografts to ABZ, 2ME and ABZ plus 2ME. Mice were inoculated with 2x106 HCT-116 cells. When the tumor size reached approximately 100 mm3, animals were randomized into six treatment groups and treated with the vehicle control, 25 mg/kg ABZ, 50 mg/kg ABZ, 25 mg/kg 2ME, 50 mg/kg ABZ plus 2ME, and 25 mg/kg ABZ plus 2ME. To assess the effect of individual drugs, animals were treated with ABZ on day 1 and the vehicle of 2ME on day 2, or ABZ vehicle on day 1 and 2ME on day 2. Combination therapy groups received ABZ on day 1 followed by 2ME 24 h later (day 2). Control animals received vehicle alone. Mice were euthanized when the tumor size reached 1000 mm3. (A) Effect of the combination of high concentration of ABZ (50 mg/kg) plus 2ME on the survival of the animals (B) Effect of the combination of low dose of ABZ (25 mg/kg) plus 2ME on the survival of the animals (C) Median survival analysis. The median survival of mice in all treatment groups was calculated using Kaplan-Meier statistics. The log-rank P-value is the comparison between each treatment group with untreated mice.