Abstract
Expression of the multidrug resistance (MDR-1) gene product, P-glycoprotein (P-170), and the stem cell antigen, CD34, at diagnosis were determined using monoclonal antibodies (MoAbs) MRK-16 and 12.8, respectively, in 130 pediatric acute myeloid leukemia (AML) patients entered onto Childrens Cancer Group (CCG) study CCG-2891. Fluorescein isothiocyanate (FITC) as a second step reagent was employed for the measurement of P-170 expression since it is commonly used in clinical laboratories. Nine of 30 (30%) infant (<1 year of age) de novo specimens expressed P-170 at levels ≥20% of control cells. In contrast, eight of 100 (8%) AML samples from older children (≥1 year of age) expressed the multidrug resistance surface protein at diagnosis. With the exception of one infant, all de novo samples that expressed P-170 also expressed CD34. Pediatric patients of any age with positive P-170 expression using MoAb MRK-16 with a FITC-conjugated second step reagent fared no worse than remaining patients treated on the same treatment with regard to induction failure, incidence of relapse, event-free survival, or overall survival. Further investigation is necessary to determine whether P-170 assay systems with greater sensitivity will distinguish pediatric AML patients with poor prognosis.
Original language | English (US) |
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Pages (from-to) | 2042-2048 |
Number of pages | 7 |
Journal | Leukemia |
Volume | 9 |
Issue number | 12 |
State | Published - Dec 1995 |
Keywords
- Acute myelogenous leukemia
- Flow cytometry
- MDR
- Multidrug resistance
- P-glycoprotein
- Treatment outcome
ASJC Scopus subject areas
- Hematology
- Oncology
- Cancer Research