Determination of imatinib intracellular uptake in leukocytes as a prognostic factor in cML therapy

Background: Imatinib is the first target therapy for chronic myelogenous leukemia (CML). Response to imatinib treatment also depends on the uptake of the drug into the target cell by organic cation transporter 1 (OCT1). OCT1 activity determined by the uptake of 14C-imatinib (IUR) in isolated mon...

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Main Authors: Eva Kralj, Simon Žakelj, Jurij Trontelj, Katja Berginc, Tadej Pajić, Irena Preložnik Zupan, Peter Černelč, Barbara Ostanek, Helena Podgornik, Janja Marc, Albin Kristl
Format: Article
Language:English
Published: Slovenian Medical Association 2012-12-01
Series:Zdravniški Vestnik
Online Access:http://vestnik.szd.si/index.php/ZdravVest/article/view/757
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author Eva Kralj
Simon Žakelj
Jurij Trontelj
Katja Berginc
Tadej Pajić
Irena Preložnik Zupan
Peter Černelč
Barbara Ostanek
Helena Podgornik
Janja Marc
Albin Kristl
author_facet Eva Kralj
Simon Žakelj
Jurij Trontelj
Katja Berginc
Tadej Pajić
Irena Preložnik Zupan
Peter Černelč
Barbara Ostanek
Helena Podgornik
Janja Marc
Albin Kristl
author_sort Eva Kralj
collection DOAJ
description Background: Imatinib is the first target therapy for chronic myelogenous leukemia (CML). Response to imatinib treatment also depends on the uptake of the drug into the target cell by organic cation transporter 1 (OCT1). OCT1 activity determined by the uptake of 14C-imatinib (IUR) in isolated mononuclear cells (MNC) has already been linked with treatment response. It has been proposed that the OCT1 activity determination could provide a valuable tool for the prediction of treatment success in patients with CML. Methods: MNC and granulocytes (Gran) of a healthy volunteer were incubated with imatinib in the presence or absence of prazosin before and after Ficoll cell sorting. The cells were lysed with liquid nitrogen and extracted with organic solvents. The intracellular concentration (ci) of imatinib was determined by LC-MS/MS method. Results: We measured the highest IUR in Gran isolated prior to incubation with imatinib. There the ci was 10-fold higher than in other cells. With prazosin, significantly lower imatinib ci were observed in MNC (1.49 ± 0.11 vs. 17.8 ± 1.6 mg/L) and Gran (96.2 ± 2.2 vs. 191.2 ± 7.7 mg/L) incubated after cell sorting. We measured the highest absolute OCT1 activity in Gran (6.27 ± 0.66 ng imatinib/200000 cells). Conclusions: We developed a procedure for the measurement of imatinib uptake into the white blood cells, which is not based on the use of radioactively labelled compounds. By means of this test, we also hope to determine the correlation of OCT1 activity with treatment success in the population of Slovenian CML patients.
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spelling doaj.art-57031ce61ace4363993b642d6f1831b02022-12-22T01:13:23ZengSlovenian Medical AssociationZdravniški Vestnik1318-03471581-02242012-12-0181SUPL II636Determination of imatinib intracellular uptake in leukocytes as a prognostic factor in cML therapyEva KraljSimon ŽakeljJurij TronteljKatja BergincTadej PajićIrena Preložnik ZupanPeter ČernelčBarbara OstanekHelena PodgornikJanja MarcAlbin KristlBackground: Imatinib is the first target therapy for chronic myelogenous leukemia (CML). Response to imatinib treatment also depends on the uptake of the drug into the target cell by organic cation transporter 1 (OCT1). OCT1 activity determined by the uptake of 14C-imatinib (IUR) in isolated mononuclear cells (MNC) has already been linked with treatment response. It has been proposed that the OCT1 activity determination could provide a valuable tool for the prediction of treatment success in patients with CML. Methods: MNC and granulocytes (Gran) of a healthy volunteer were incubated with imatinib in the presence or absence of prazosin before and after Ficoll cell sorting. The cells were lysed with liquid nitrogen and extracted with organic solvents. The intracellular concentration (ci) of imatinib was determined by LC-MS/MS method. Results: We measured the highest IUR in Gran isolated prior to incubation with imatinib. There the ci was 10-fold higher than in other cells. With prazosin, significantly lower imatinib ci were observed in MNC (1.49 ± 0.11 vs. 17.8 ± 1.6 mg/L) and Gran (96.2 ± 2.2 vs. 191.2 ± 7.7 mg/L) incubated after cell sorting. We measured the highest absolute OCT1 activity in Gran (6.27 ± 0.66 ng imatinib/200000 cells). Conclusions: We developed a procedure for the measurement of imatinib uptake into the white blood cells, which is not based on the use of radioactively labelled compounds. By means of this test, we also hope to determine the correlation of OCT1 activity with treatment success in the population of Slovenian CML patients.http://vestnik.szd.si/index.php/ZdravVest/article/view/757
spellingShingle Eva Kralj
Simon Žakelj
Jurij Trontelj
Katja Berginc
Tadej Pajić
Irena Preložnik Zupan
Peter Černelč
Barbara Ostanek
Helena Podgornik
Janja Marc
Albin Kristl
Determination of imatinib intracellular uptake in leukocytes as a prognostic factor in cML therapy
Zdravniški Vestnik
title Determination of imatinib intracellular uptake in leukocytes as a prognostic factor in cML therapy
title_full Determination of imatinib intracellular uptake in leukocytes as a prognostic factor in cML therapy
title_fullStr Determination of imatinib intracellular uptake in leukocytes as a prognostic factor in cML therapy
title_full_unstemmed Determination of imatinib intracellular uptake in leukocytes as a prognostic factor in cML therapy
title_short Determination of imatinib intracellular uptake in leukocytes as a prognostic factor in cML therapy
title_sort determination of imatinib intracellular uptake in leukocytes as a prognostic factor in cml therapy
url http://vestnik.szd.si/index.php/ZdravVest/article/view/757
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