Figure 6.

The Combination of TG-101348 with SGI-1776 Is Synergistic in CRC

(A) Percentage of growth inhibition of single-agent TG-101348 or SGI-1776 and combination treatment in HCT116 and SW480, as indicated by heatmaps (left). Synergism of growth inhibition by combined treatment with TG-101348 and SGI-1776 in HCT116 and SW480 cells, as analyzed by an isobologram analysis (right). (B) A colony formation assay was performed with HCT116 and SW480 cells treated with DMSO, 1 μM TG-101348, 2.5 μM SGI-1776, and the combination treatment. (C) Bar plots indicate the number of colonies. (D) Caspase-3/7 enzymatic activity was measured using an Apo-ONE homogeneous caspase-3/7 assay in HCT116 and SW480 cells treated with DMSO, 1 μM TG-101348, 2.5 μM SGI-1776, and the combination treatment. (E) Representative western blot analysis of cleaved caspase-3, cleaved PARP, BCL-2, and Bax protein expression in HCT116 and SW480 cells treated with DMSO, 1 μM TG-101348, 2.5 μM SGI-1776, and the combination treatment. GAPDH was used as a protein loading control. (F) Tumor volumes over 29 days in an orthotopic model of HCT116 cells treated with DMSO, TG-101348, SGI-1776, or the combination treatment. Representative images are of tumor tissues that were recovered from each group. (G) Representative micrographs of Ki67 expression in tumors treated with DMSO, TG-101348, SGI-1776, or the combination treatment. Scale bars, 100 μm. (H) Scatter dot plots indicate the percentage of Ki67 positivity in tumors from each group. Error bars represent the mean ± SEM. ∗∗p < 0.01; ∗∗∗p < 0.001, two-tailed, unpaired t tests.