Theoretical and practical considerations for the measurement of P-glycoprotein function in acute myeloid leukemia

摘要: This paper summarizes experimental data and theoretical con- are the level of sensitivity that is deemed relevant for study siderations, important measurement P-glyco- practicability reproducibility methodology protein (Pgp) function in acute myeloid leukemia (AML). The local clinical laboratory setting. Three useful goals presented subdivisions based on techniques to be considered are: used, which will facilitate finding specific information. Based our extensive experience with Pgp analysis, includes (1) To identify those AMLs highest expression Pgp. radioactive assays, flow cytometry fluorescence A minority de novo AML samples (20% at most 10 ) microscopy, we recommend a cytometry-based assay, have clearly higher than bulk measures effect 2 mM PSC 833 rhodamine 123 (R123) accumulation as practical sensitive func- samples. allows fairly simple categorization tional test. In combination cytometric Pgp-negative (which actually means using an antibody against extracellular below certain level) or Pgp-positive. epitope (eg MRK16), this offers reproducible (2) aim classifying scale method detection AML, also rapid prac- expression, principle may translated into tical. Furthermore, R123 assay drug transporter molecules intracellular Pgp, because transported much less efficiently by multidrug resistance (MRP) Another probe concentration drug. similar specificity 3,39-diethyloxacarbocy- (3) determine particular subpopulanine iodide. Alternatively, especially analysis small ation cells, eg CD34 + cells instead addition numbers (for example sorted subpopulations leu- whole population mean. kemic cells), convenient procedures being developed DNA-binding substrates remain following discussion methods fixed nuclei upon formaldehyde exposure light these goals. Dealing same questions, merquantitative laser scanning microscopy its different been discussed image analysis. Less published more general way previously. 12 establish optimal conditions dual parameter (Pgp function, Pgp+ CD34+ cells). However,