Table 2. The IC50 of TKIs for the inhibition of UGT activities.
| Axitinib (μM) | Imatinib (μM) | Lapatinib (μM) | Vandetanib (μM) | |
|---|---|---|---|---|
| UGT1A1 | NDa | 11.0 ± 2.8 | 0.5 ± 0.0 | ND |
| UGT1A3 | ND | ND | ND | ND |
| UGT1A4b | 14.2 ± 3.2 | ND | 3.8 ± 0.7 | ND |
| UGT1A7 | 3.3 ± 0.7 | 19.5 ± 4.1 | 2.7 ± 1.4 | 38.9 ± 4.3 |
| UGT1A8 | ND | 22.9 ± 3.8 | ND | ND |
| UGT1A9 | 3.6 ± 0.7 | ND | ND | 5.0 ± 0.4 |
| UGT1A10 | ND | 47.3 ± 7.6 | ND | ND |
| UGT2B7 | ND | 68.4 ± 10.8 | ND | ND |
| UGT2B15 | ND | 91.0 ± 18.3 | ND | ND |
| UGT2B17 | ND | 0.8 ± 0.1 | ND | ND |
anot determined; based on results from preliminary experiments showing that the extent of UGT inhibition at 100 μM of a respective TKI was <50%.
bTFP was used as a substrate.