Table II.
IC50 values of cisplatin in NSCLC cells when administered alone or in combination with ECL, the CI and drug interactions of ECL and cisplatin combination.
| NSCLC cell lines | Treatment | IC50 (µM) | Combination index (CI) | Drug interactions |
|---|---|---|---|---|
| A549 | Cisplatin | 53.58±3.05 | – | – |
| Cisplatin + ECL(IC20) | 30.16±2.62 | 0.66±0.06 | Synergism | |
| Cisplatin + ECL(IC40) | 17.91±2.11 | 0.91±0.04 | Additive | |
| Calu-1 | Cisplatin | 135.49±7.83 | – | – |
| Cisplatin + ECL(IC20) | 72.49±2.05 | 0.60±0.04 | Synergism | |
| Cisplatin + ECL(IC40) | 29.53±3.71 | 0.73±0.03 | Synergism |
IC50, the concentrations required for 50% inhibition of cell viability. The values (µM) are expressed as the mean ± SD of three independent experiments. CI were analyzed using the Chou-Talalay method which reflects drug interactions; CI <0.9, CI=0.9–1.1, and CI >1.1 indicated synergistic, additive, and antagonistic effects, respectively. NSCLC, non-small cell lung cancer; ECL, eurycomalactone; CI, combination index.