The influence of PRI-2205 on the antitumor activity of 5-FU in MC38 colon cancer. PRI-2205 was administered at a dose of 10 μg/kg/day, s.c., three times a week, from day 1 to 22, 5-FU at a dose of 75 mg/kg/day, i.p., on the first day. Black arrow indicate day of 5-FU administration, gray arrows – days of PRI-2205 administration. A) Kinetics of tumor growth (mean of tumor volume). P < 0.05: 5-FU combined with PRI-2205 in comparison to the control from days 10 to 27 (Kruskal-Wallis ANOVA Multiple Comparisons P values (2-tailed) test). B) Tumor growth inhibition (TGI) and hypothetical TGI values were calculated from days 13 to 27 of the experiment (median of tumor volume). C) Survival analysis of treated and untreated mice. Number of mice: control - 10; in the each treatment group – 8. Statistical analysis was performed for tumor growth inhibition.