Figure 2.

ATO reduces EpCAM⁺CD44⁺ HCT-116 cell viability in hypoxia. (A) EpCAM⁺CD44⁺ HCT-116 cells treated with ATO (0-20 µM) for 24 h under hypoxic conditions were assessed for cell viability using an MTS assay. (B and C) ATO (15 µM) inhibited the tumorsphere formation capacity of EpCAM⁺CD44⁺ HCT-116 cells under hypoxic conditions. Cells treated with 50 µM DDP used as a positive control. (B) Quantified results and (C) representative microscopy images of the tumorspheres (scale bar, 200 µm). Values are expressed as the mean ± standard deviation of three independent experiments. ^**P<0.01 and ^****P<0.0001 vs. DMSO; ^#P<0.05 and ^##P<0.01 vs. DDP as determined by one-way ANOVA followed by Dunnett's test. DDP, cisplatin; ATO, atovaquone; EpCAM, epithelial cell adhesion molecule.