Mechanisms of cellular resistance to imatinib in human chronic myeloid leukemia cells

Ural, Ali Ugur
Gündüz, Ufuk
A major advancement in the treatment of chronic myeloid leukemia (CML) has been the development of imatinib, which has shown striking activity in the chronic phase and the accelerated phase, but less so in the blast phase of the disease. Despite high rates of hematologic and cytogenetic responses to therapy, the emergence of resistance to imatinib has been recognized as a major problem in the treatment of patients with CML.


Reversal of multidrug resistance by synthetic and natural compounds in drug-resistant MCF-7 cell lines
Kars, Meltem Demirel; Iseri, Ozlem Darcansoy; Gündüz, Ufuk; Molnar, Jozsef (2008-01-01)
Background: Ineffectiveness of anticancer drugs is frequently observed in cancer chemotherapy. The resistance of tumor cells to various cytotoxic drugs is defined as multidrug resistance (MDR). The purpose of this study is to investigate the potential reversal effect of some synthetic and natural chemicals on drug-resistant MCF-7 cell lines. The effects of potential MDR modulators combined with some anticancer drugs were also studied. Methods: Flow cytometry, MTT cytotoxicity assays and checkerboard combina...
Expression of Multidrug Resistance 1, Lung Resistance Protein and Breast Cancer Resistance Protein Genes in Chronic Leukemias
Iseri, Ozlem D.; Kars, Meltem D.; Mutlu, Pelin; Avcu, Ferit; Ural, Ali U.; Gündüz, Ufuk (2011-01-01)
One of the major problems in treatment of leukemias is multidrug resistance, which is already present at diagnosis or develops after chemotherapy. The gene expression levels of multidrug resistance resistance 1 (MDR1), breast cancer resistance protein (BCRP) and lung resistance-resistance protein (LRP) were evaluated in blood samples of 20 CLL and 24 CML patients using RT-PCR. MDR1, BCRP and LRP expression levels were detected in 65%, 20% and 45% of CLL patients, and in 54%, 37% and 25% of CML patients, res...
Reversal of multidrug resistance in mcf-7 breast adenocarcinoma cell line by silencing interleukin 6 with RNA interference
Çakmak, Neşe; Gündüz, Ufuk; Department of Biology (2013)
Multidrug resistance (MDR) in cancer is characterized by development of resistance to several unrelated drugs upon long time administration of a certain type of chemotherapeutic agent. In doxorubicin resistant MCF-7 cell line, resistance is developed mainly by upregulation of MDR1 gene which encodes an ABC transporter protein known as P-glycoprotein. Interleukin 6 (IL-6) is a cytokine which acts as a growth factor for certain cell types including some cancer cells. IL-6 is found at high levels in cancer pat...
Apoptotic Effects of Resveratrol, a Grape Polyphenol, on Imatinib-Sensitive and Resistant K562 Chronic Myeloid Leukemia Cells
Can, Geylani; Cakir, Zeynep; Kartal, Melts; Gündüz, Ufuk; BARAN, YUSUF (2012-07-01)
Aim: To examine the antiproliferative and apoptotic effects of resveratrol on imatinib-sensitive and imatinib-resistant K562 chronic myeloid leukemia cells. Materials and Methods: Antiproliferative effects of resveratrol were determined by the 3-Bis[2-methoxy-4-nitro-5-sulphophenyl]-2H-tetrazolium-5-carboxanilide inner salt (XTT) cell proliferation assay. Apoptotic effects of resveratrol on sensitive K562 and resistant K562/IMA-3 cells were determined through changes in caspase-3 activity, loss of mitochond...
Reversal of paclitaxel resistance in MCF-7 cell line by achemical modulator elacridar
Şener, Emine Çiğdem; Gündüz, Ufuk; Department of Biology (2012)
The phenomenon called multi drug resistance (MDR) is the resistance of cancer cells to anticancer drugs before or during chemotherapy. One of the mechanisms causing MDR is the upregulation of efflux pumps. The overexpression of MDR1 and MRP1 results in increased efflux of anticancer agents. The aim of this study was to reverse MDR1-mediated paclitaxel resistance in MCF7 breast cancer cell line by a chemical MDR modulator elacridar. In this study, cytotoxicity and the reversal effect of elacridar on sensitiv...
Citation Formats
Y. BARAN, A. U. Ural, and U. Gündüz, “Mechanisms of cellular resistance to imatinib in human chronic myeloid leukemia cells,” HEMATOLOGY, pp. 497–503, 2007, Accessed: 00, 2020. [Online]. Available: