Supplementary Figure 2 from Constitutively Active ErbB2 Regulates Cisplatin-Induced Cell Death in Breast Cancer Cells via Pro- and Antiapoptotic Mechanisms

Abstract

<p>Supplementary figure 2: Inhibition of ATM and knockdown of noxa, caspase-9, μ-calpain and cathepsin B. MCF-7 vector (V) and ΔNErbB2 (ΔN) cells were washed free of tetracycline 72 h before the experiment. Cells were exposed to KU-55933 (10 μM) for 19 h, cisplatin (25 μM) or control conditions for 18 h and subsequently processed for immunoblotting (A-B). Top panels show representative immunoblots, lower panels show protein level relative to that in vector cells under control conditions. A. p-ATM B. p-p53. ΔNErbB2 cells were washed and transfected with siRNA (200nM) 72 h before the experiment. Cells were exposed to cisplatin (25 μM), and subsequently processed for immunoblotting (C-F). Top panels show representative immunoblots, lower panels show protein level relative to that in cells transfected with mock control. C. Noxa D. Caspase-9. E. μ-calpain. F. Cathepsin B. Data are representative of 3-4 independent experiments for each condition. Western blot data are shown as means with SEM error bars. * indicates comparison of the value in cisplatin treated to that in the respective cell line control, # indicate comparison of values in vector- and ΔNErbB2 cell lines under same treatment. */#, **/##, ***/### and ****/#### indicate p < 0.05, p < 0.01, p < 0.001 and p < 0.0001, respectively (C-F), one-way ANOVA with Bonferroni post-test) (A-B, two-way ANOVA with Bonferroni post-test).</p>