Table 1.
The in vitro antiproliferative effect against human A549 cells of imatinib mesylate combined with PRI-2191 alone or applied with cisplatin (CIS), idarubicin (ID) or docetaxel (DTX).
| Cytostatic (μg/mL) | Dose of PRI-2191 (nM)/Imatinib IC50 (μg/mL) | |||||
|---|---|---|---|---|---|---|
| 100 | 10 | 0 | ||||
| IC50 | CI * | IC50 | CI * | IC50 | CI * | |
| ** | 15.71 ± 4.56 | Additive * | 14.88 ± 3.05 | Additive * | 22.38 ± 2.07 | *** |
| DTX 0.001 | 7.05 ± 3.51 | 0.629 | 7.01 ± 2.43 | 0.627 | 18.55 ± 8.63 | 1.266 |
| 0.0001 | 16.84 ± 1.4 | 0.794 | 20.03 ± 1.65 | 0.94 | 19.67 ± 6.01 | 0.924 |
| CIS 0.1 | 13.77 ± 1.37 | 0.894 | 14.91 ± 3.23 | 0.954 | 16.28 ± 2.12 | 1.025 |
| 0.01 | 16.86 ± 2.23 | 0.784 | 16.2 ± 4.24 | 0.754 | 19.9 ± 3.28 | 0.922 |
| ID 0.001 | 1.42 ± 1.04 | 0.783 | 4.24 ± 0.88 | 0.995 | 3.08 ± 0.5 | 0.908 |
| 0.0001 | 15.2 ± 2.8 | 0.793 | 20.34 ± 2.59 | 1.038 | 24.07 ± 2.09 | 1.216 |
IC50 value for tacalcitol (PRI-2191) alone above 1000 nM; * counted on the basis of proliferation inhibition plots. CI, combination index counted for imatinib mesylate combined with the given cytostatic with or without tacalcitol. A combination index of CI < 0.8 indicated synergism, CI > 1.2 antagonism and CI = 0.8–1.2 an additive effect; ** IC50 value for Imatinib without cytostatics; *** CI is countless. The IC50 values presented are the mean ± SD obtained for 3–5 separate experiments.