Alves Raquel, Gonçalves Ana Cristina, Jorge Joana, Almeida António M, Sarmento-Ribeiro Ana Bela
Laboratory of Oncobiology and Hematology (LOH) and University Clinic of Hematology, Faculty of Medicine University of Coimbra (FMUC), University of Coimbra, 3000-548 Coimbra, Portugal.
Coimbra Institute for Clinical and Biomedical Research (iCBR)-Group of Environmental Genetics of Oncobiology (CIMAGO), FMUC, University of Coimbra, 3000-548 Coimbra, Portugal.
Biomedicines. 2022 May 17;10(5):1158. doi: 10.3390/biomedicines10051158.
Multidrug resistance (MDR) development has emerged as a complication that compromises the success of several chemotherapeutic agents. In chronic myeloid leukemia (CML), imatinib resistance has been associated with changes in and intracellular drug concentration, controlled by SLC and ABC transporters. We evaluate the therapeutic potential of a P-glycoprotein and BCRP inhibitor, elacridar, in sensitive (K562 and LAMA-84) and imatinib-resistant (K562-RC and K562-RD) CML cell lines as monotherapy and combined with imatinib. Cell viability was analyzed by resazurin assay. Drug transporter activity, cell death, cell proliferation rate, and cell cycle distribution were analyzed by flow cytometry. Both resistant models presented an increased activity of BCRP and P-gP compared to K562 cells. Elacridar as monotherapy did not reach IC in any CML models but activated apoptosis without cytostatic effect. Nevertheless, the association of elacridar (250 nM) with imatinib overcomes resistance, re-sensitizing K562-RC and K562-RD cells with five and ten times lower imatinib concentrations, respectively. Drug combination induced apoptosis with increased cleaved-caspases-3, cleaved-PARP and DNA damage, reduced cell proliferation rate, and arrested CML cells in the S phase. These data suggest that elacridar combined with imatinib might represent a new therapeutic option for overcoming TKI resistance involving efflux transporters.
多药耐药（MDR）的出现已成为一种并发症，影响了多种化疗药物的治疗效果。在慢性粒细胞白血病（CML）中，伊马替尼耐药与SLC和ABC转运蛋白控制的细胞内药物浓度变化有关。我们评估了P-糖蛋白和乳腺癌耐药蛋白（BCRP）抑制剂艾拉司群作为单一疗法以及与伊马替尼联合使用时，对敏感（K562和LAMA-84）和伊马替尼耐药（K562-RC和K562-RD）CML细胞系的治疗潜力。通过刃天青法分析细胞活力。通过流式细胞术分析药物转运蛋白活性、细胞死亡、细胞增殖率和细胞周期分布。与K562细胞相比，两种耐药模型的BCRP和P-糖蛋白活性均增加。艾拉司群作为单一疗法在任何CML模型中均未达到半数抑制浓度（IC），但可激活细胞凋亡而无细胞生长抑制作用。然而，艾拉司群（250 nM）与伊马替尼联合使用可克服耐药性，使K562-RC和K562-RD细胞分别对低五倍和十倍浓度的伊马替尼重新敏感。药物联合使用可诱导细胞凋亡，增加半胱天冬酶-3、聚腺苷二磷酸核糖聚合酶（PARP）的裂解和DNA损伤，降低细胞增殖率，并使CML细胞停滞于S期。这些数据表明，艾拉司群与伊马替尼联合使用可能是克服涉及外排转运蛋白的酪氨酸激酶抑制剂（TKI）耐药性的一种新的治疗选择。
