Fig. 5: ATM is required for ZEB1-mediated chemoresistance

a–c The specific shRNA targeting ATM or scramble shRNA was introduced into ZEB1/231 cells, followed by treatment with different concentrations of EPI for 48 h. a Cell growth inhibition was determined by cell viability assay. *P < 0.05, ***P < 0.001 vs respective control in one-way ANOVA followed by Tukey’s honestly significant difference test. b EPI-induced expression of γH2AX protein was determined by immunoblotting and normalized to the levels of H2AX. Cropped blots are shown (full-sized blots are presented in Supplementary Fig. S13). c EPI-induced formation of γH2AX nucleic foci was measured by immunofluorescent staining. At least 500 nuclei were counted and the percentage of γH2AX-postitive nuclei was determined. **P < 0.01 vs respective control in Student’s t test. Scale bars, 20 μm. d, e ZEB1/231 cells were treated with 10 μM KU-55933, followed by treatment with the indicated concentrations of EPI for 48 h. EPI-induced cell viability inhibition (d) and formation of γH2AX nucleic foci (e) were determined. *P < 0.05, ***P < 0.001 vs respective control in Student’s t test