Figure 6.

Actinomycin D and ABT-737 synergistically kill NSCLC tumor cells. (A) Upon treatment with different combinations of actinomycin D and ABT-737 for 48 hours, the percentage of cell death of human lung carcinoma A549 cells was measured. The data depict mean ± standard deviation of triplicate experiments. (B) The levels of different anti-apoptotic Bcl-2 proteins in A549 cell lysates (30 µg) under the indicated conditions were determined by western blot. Actin represents a control for protein loading. (C) A549 cells were treated with various combinations of actinomycin D (5–300 ng/ml) and ABT-737 (0.83–50 µM) at a fixed concentration ratio for 48 hours and cell death was measured. The values of combination index (CI) were determined as described in Materials and Methods. (D) Upon 80 hour-treatment with various concentrations of actinomycin D (0.64–16 ng/ml) and ABT-737 (2–50 µM) at a fixed dose ratio, the percentage of NCI-H1299 cell death was determined and CI values were computed as described in Materials and Methods. All experiments were performed independently three times.