Table 2. IC50 Values and Combination Index and Dose Reduction Ratio (DRI) for IC50 Effect of TMZ+BTZa.
| IC50 (nM) |
DRI |
||||
|---|---|---|---|---|---|
| cell line | TMZ | TMZ+BTZ | CI | TMZ | BTZ |
| U251 | (4.1 ± 1.0) × 104 | 26.1 ± 5.6 | 0.576 | 2.13 × 105 | 1.74 |
| T98G | (1.2 ± 0.9) × 106 | 78.4 ± 10.1 | 0.134 | 6.43 × 106 | 7.46 |
a
The CI value indicates if the effect of the combined therapy is antagonistic (CI > 1), additive (CI = 1), or synergic (CI < 1). DRI is the dose reduction (in fold) needed to achieve the same survival inhibition when the cells are treated with each drug individually.