Effect of ABCG2, OCT1, and ABCB1 (MDR1) Gene Expression on Treatment-Free Remission in a EURO-SKI Subtrial

Please always quote using this URN: urn:nbn:de:bvb:20-opus-226281
  • Within the EURO-SKI trial, 132 chronic phase CML patients discontinued imatinib treatment. RNA was isolated from peripheral blood in order to analyze the expression of MDR1, ABCG2 and OCT1. ABCG2 was predictive for treatment-free remission in Cox regression analysis. High transcript levels of the ABCG2 efflux transporter (>4.5 parts per thousand) were associated with a twofold higher risk of relapse. Introduction: Tyrosine kinase inhibitors (TKIs) can safely be discontinued in chronic myeloid leukemia (CML) patients with sustained deepWithin the EURO-SKI trial, 132 chronic phase CML patients discontinued imatinib treatment. RNA was isolated from peripheral blood in order to analyze the expression of MDR1, ABCG2 and OCT1. ABCG2 was predictive for treatment-free remission in Cox regression analysis. High transcript levels of the ABCG2 efflux transporter (>4.5 parts per thousand) were associated with a twofold higher risk of relapse. Introduction: Tyrosine kinase inhibitors (TKIs) can safely be discontinued in chronic myeloid leukemia (CML) patients with sustained deep molecular response. ABCG2 (breast cancer resistance protein), OCT1 (organic cation transporter 1), and ABCB1 (multidrug resistance protein 1) gene products are known to play a crucial role in acquired pharmacogenetic TKI resistance. Their influence on treatment-free remission (TFR) has not yet been investigated. Materials and Methods: RNA was isolated on the last day of TKI intake from peripheral blood leukocytes of 132 chronic phase CML patients who discontinued TKI treatment within the European Stop Tyrosine Kinase Inhibitor Study trial. Plasmid standards were designed including subgenic inserts of OCT1, ABCG2, and ABCB1 together with GUSB as reference gene. For expression analyses, quantitative real-time polymerase chain reaction was used. Multiple Cox regression analysis was performed. In addition, gene expression cutoffs for patient risk stratification were investigated. Results: The TFR rate of 132 patients, 12 months after TKI discontinuation, was 54% (95% confidence interval [CI], 46%-62%). ABCG2 expression (parts per thousand) was retained as the only significant variable (P=.02; hazard ratio, 1.04; 95% CI, 1.01-1.07) in multiple Cox regression analysis. Only for the ABCG2 efflux transporter, a significant cutoff was found (P=.04). Patients with an ABCG2/GUSB transcript level >4.5 parts per thousand (n=93) showed a 12-month TFR rate of 47% (95% CI, 37%-57%), whereas patients with low ABCG2 expression (<= 4.5 parts per thousand; n=39) had a 12-month TFR rate of 72% (95% CI, 55%-82%). Conclusion: In this study, we investigated the effect of pharmacogenetics in the context of a CML treatment discontinuation trial. The transcript levels of the efflux transporter ABCG2 predicted TFR after TKI discontinuation. (C) 2018 The Authors. Published by Elsevier Inc.show moreshow less

Download full text files

Export metadata

Additional Services

Share in Twitter Search Google Scholar Statistics
Metadaten
Author: Sébastien Rinaldetti, Markus Pfirrmann, Kirsi Manz, Joelle Guilhot, Christian Dietz, Panayiotidis Panagiotidis, Birgit Spiess, Wolfgang Seifarth, Alice Fabarius, Martin Müller, Maria Pagoni, Maria Dimou, Jolanta Dengler, Cornelius F. Waller, Tim H. Brümmendorf, Regina Herbst, Andreas Burchert, Carsten Janßen, Maria Elisabeth Goebeler, Philipp J. Jost, Stefan Hanzel, Philippe Schafhausen, Gabriele Prange-Krex, Thomas Illmer, Viktor Janzen, Martine Klausmann, Robert Eckert, Gerd Büschel, Alexander Kiani, Wolf-Karsten Hofmann, François-Xavier Mahon, Susanne Saussele
URN:urn:nbn:de:bvb:20-opus-226281
Document Type:Journal article
Faculties:Medizinische Fakultät / Medizinische Klinik und Poliklinik II
Language:English
Parent Title (English):Clinical Lymphoma, Myeloma & Leukemia
Year of Completion:2018
Volume:18
Issue:4
Pagenumber:266-271
Source:Clinical Lymphoma, Myeloma & Leukemia, Vol. 18, No. 4, 266-71
DOI:https://doi.org/10.1016/j.clml.2018.02.004
Dewey Decimal Classification:6 Technik, Medizin, angewandte Wissenschaften / 61 Medizin und Gesundheit / 610 Medizin und Gesundheit
Tag:ABCG2; Biomarker; CML; Imatinib; Prediction
Release Date:2022/01/07
Licence (German):License LogoCC BY-NC-ND: Creative-Commons-Lizenz: Namensnennung, Nicht kommerziell, Keine Bearbeitungen 4.0 International