Fig. 6

Effect of combined treatment with cisplatin and MHY4571 in NCI-H1703 cells. NCI-H1703 cells were incubated for 24 h treatment with 1:1 drug mixture (cisplatin/MHY4571) in increasing concentrations. Combined effects were determined using A MTT assay and B CI values. Results are mean ± SD, n = 3, expressed as a percentage of that in vehicle-treated control cells. (*P < 0.05, **P < 0.01, and ***P < 0.001 vs. MHY4571-treated cells). C Annexin V-FITC binding and PI uptake in non-permeabilized cells were analyzed by flow cytometry. D Colony formation assays of crystal violet-stained colonies. *P < 0.05, **P < 0.01, and ***P < 0.001 vs. vehicle-treated cells; #P < 0.05 and ##P < 0.01 vs. MHY4571-treated cells (student’s t-test). E NCI-H1703 cells and BEAS-2B cells were incubated with or without 7.5 μg/mL cisplatin and/or 7.5 μM MHY4571 for 24 h, and combined effects were assessed using MTT assay. ###P < 0.001 for the combination of cisplatin plus MHY4571 vs. cisplatin-treated cells (student’s t-test). F Total proteins were prepared and immunoblotted for PARP, procaspase-3, P-Akt, Akt, P-ERK, and ERK. β-actin was used as a loading control