MDR-1 Analysis of Blasts From AML Patients Obtained Before PSC-MEC Induction Chemotherapy
| No. of Patients . | P-gp Function . | Leukemic Blast Immunophenotype . | |
|---|---|---|---|
| P-gp+ (%) Median (range) . | CD34+(%) Median (range) . | ||
| 8 | PSC 833 inhibitable | 49 (27-96)6-150 | 95 (16-98)6-151 |
| 7 | PSC 833 noninhibitable | 17 (1-40) | 51 (4-86) |
| 15 | Total | 37 (1-96) | 85 (4-98) |
| No. of Patients . | P-gp Function . | Leukemic Blast Immunophenotype . | |
|---|---|---|---|
| P-gp+ (%) Median (range) . | CD34+(%) Median (range) . | ||
| 8 | PSC 833 inhibitable | 49 (27-96)6-150 | 95 (16-98)6-151 |
| 7 | PSC 833 noninhibitable | 17 (1-40) | 51 (4-86) |
| 15 | Total | 37 (1-96) | 85 (4-98) |
Leukemic blasts were evaluated for MDR-1 immunophenotype using the 4E3 monoclonal anti–P-gp antibody. MDR-1 function was evaluated using the rhodamine-123 efflux assay and its inhibitability by PSC, as defined in Materials and Methods.
P = .004, PSC 833 inhibitable versus PSC 833 noninhibitable.
P = .02, PSC 833 inhibitable versus PSC 833 noninhibitable.