Fig. 4

AG-120 is a potent wild-type IDH1 inhibitor under low glucose and magnesium conditions. A Representative images of high glucose (25 mM) and B low glucose (2.5 mM) colony formation assays in the A375 cell line. Cells were treated with vehicle control and AG-120 (1 μM) under the indicated conditions, and stained with crystal violet solution. Quantification (%) is shown in the graphs. C Under high glucose and D low glucose conditions, phase-contrast images (4X magnification) were taken after treated with vehicle control or AG-120 (1 μM) for 4 days under indicated nutrient conditions. E Representative image of excised and in vivo tumors of A375. F Tumor growth curves of A375 melanoma xenografts in nude mice. Tumor sizes were assessed twice per week using calipers (n = 5 per group). G Average tumor volume of A375 xenografts at the end of the experiment (day 26) (n = 5 tumors per group). H Average tumors weights (mg) of A375 xenografts in each group (n = 5 per group). I Body weights of A375 melanoma xenografts in nude mice (n = 5 per group). J Cell mitoses in tumor xenografts were estimated by nuclear immunolabeling (Ki-67). Scale bar, 50 μm. Each data point represents the mean ± SEM of three independent experiments. N.S., nonsignificant; *, P < 0.05; **, P < 0.01; ***, P < 0.001; ****, P < 0.0001