Efflux parameters of anthracycline derivatives by K562/ADR cells
| Anthracycline | ka | VM | Km | nH |
|---|---|---|---|---|
| ×1010 s−1 (cells/ml)−1 | × 10−5 molecules/cell/sec | μm | ||
| eso-DNR | 14 | 26.4 ± 5.4 | 1.7 ± 0.7 | 1.2 ± 0.4 |
| DNR | 8 | 20.4 ± 1.8 | 2.1 ± 0.3 | 1.9 ± 0.4 |
| PIRA | 32 | 15.0 ± 3.0 | 0.4 ± 0.2 | 1.3 ± 0.4 |
| Br-DNR | 28 | 11.4 ± 3.0 | 0.4 ± 0.2 | 1.3 ± 0.7 |
| OH-DNR | 5 | 15.6 ± 3.6 | 2.4 ± 0.7 | 1.8 ± 0.6 |
| OH-DOX | 6 | 21.0 ± 2.4 | 2.4 ± 0.3 | 2.3 ± 0.5 |
Data are mean ± standard deviation of three to five independent experiments on different days. k a was calculated using eq. 5, where VM was expressed in m/sec/(cells/ml), the conversion being 1m/sec/(cells/ml) = 6 × 1014molecules/cell/sec.