Fig. 5

Lowering NSMCE2 transcript levels sensitizes breast cancer cells to chemotherapeutic agents. A SE blockade and doxorubicin synergize to induce apoptosis in breast cancer cells. BT549 and Hs578T were preincubated with vehicle (DMSO) or 1 μM JQ1 for 24 h, after which culture medium was replaced by fresh medium containing vehicle or 1 μM JQ1 ± 1 μM doxorubicin. After 48 h, apoptotic cells were quantified by Annexin V staining. Two Way ANOVA followed by Bonferroni’s multiple comparison test was performed, **P <  0.01, ***P <  0.001. B SE blockade and paclitaxel combination does not induce apoptosis in breast cancer cells. BT549 and Hs578T were preincubated with vehicle or 1 μM JQ1 for 24 h, after which culture medium was replaced by fresh medium containing vehicle or 1 μM JQ1 ± 5 nM paclitaxel. After 48 h, apoptotic cells were quantified by Annexin V staining. Two Way ANOVA followed by Bonferroni’s multiple comparison test was performed, **P <  0.01, ***P <  0.001. C Knocking down NSMCE2 sensitizes breast cancer cells to chemotherapeutic drugs. BT549 and Hs578T transduced with shControl or shNSMCE2 were incubated with 0.5 μM doxorubicin for 48 h or 5 nM paclitaxel for 72 h. After treatment, viable cells were quantified by MTT assay. Plots show the percentage of cell viability for the treatment relative to vehicle. Two Way ANOVA followed by Bonferroni’s multiple comparison test was performed, *P <  0.05, **P <  0.01, ***P <  0.001. D NSMCE2 RNA expression increases upon doxorubicin treatment but not upon paclitaxel in BT549 and Hs578T. Cells were treated with 1 μM doxorubicin or 5 nM paclitaxel for 24 h and NSMCE2 levels were quantified by qPCR. ANOVA followed by Dunnett’s multiple comparison test was performed, *P <  0.05; **P <  0.01. E) NSMCE2 RNA upregulation by doxorubicin is mediated by SEs. BT549 and Hs578T were treated with 1 μM JQ1 and/or 1 μM doxorubicin for 24 h and NSMCE2 RNA expression was determined by qPCR. Two Way ANOVA followed by Bonferroni’s multiple comparison test was performed, **P <  0.01