Barzegar Mohieddin, Allahbakhshian Farsan Mehdi, Amiri Vahid, Mohammadi Saeed, Shahsavan Shaghayegh, Mirzaeian Amin, Mohammadi Mohammad Hossein
Department of Hematology and Blood Banking, School of Allied Medical Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
HSCT Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
Iran J Pharm Res. 2021 Winter;20(1):384-397. doi: 10.22037/ijpr.2020.113272.14199.
In spite of successful initial remission, chemo-resistance and relapse are still concerning points in acute myeloid leukemia (AML) treatment strategies. Multidrug resistance (MDR) appears to be the major contributor of chemo-resistance, arising in some sub-clones of cancers and could be developed in others. The aim of this study was to investigate the role of extracellular vesicles (EVs) derived from AML patients on the transmission of chemo-resistance phenotype. Ultracentrifugation was employed to isolate EVs from healthy controls, new cases, and relapsed AML patients. The EVs size, morphology, and immunophenotype were determined by dynamic light scattering, TEM, and flow cytometry respectively. Bradford assay was performed to measure the protein content of EVs. MTT assay and flow cytometry analysis were also used to determine the viability index, induction of apoptosis, and ROS generation in U937 cells. The expression level of two efflux pumps was assessed using qRT-PCR analysis. Findings of TEM, DLS, and flow cytometry confirmed that EVs had a desirable shape, size, and surface markers. EVs derived from both new cases and relapsed AML patients significantly reduced idarubicin-induced apoptosis in the U937 cells. The analysis of drug efflux pumps gens revealed that EVs over-express and in the target cells. These findings suggested a novel role of EVs in mediating the acquired chemo-resistance in AML patients by inducing the expression of the drug efflux pumps; however, further investigations will be required to elucidate other underlying mechanisms of resistance that are mediated by EVs.
尽管急性髓系白血病（AML）初始缓解成功，但化疗耐药和复发仍是治疗策略中的关注点。多药耐药（MDR）似乎是化疗耐药的主要原因，出现在某些癌症亚克隆中，也可能在其他亚克隆中产生。本研究的目的是探讨AML患者来源的细胞外囊泡（EVs）在化疗耐药表型传递中的作用。采用超速离心法从健康对照、新发病例和复发AML患者中分离EVs。分别通过动态光散射、透射电子显微镜（TEM）和流式细胞术测定EVs的大小、形态和免疫表型。采用Bradford法测定EVs的蛋白质含量。MTT法和流式细胞术分析也用于测定U937细胞的活力指数、凋亡诱导和活性氧（ROS）生成。使用qRT-PCR分析评估两种外排泵的表达水平。TEM、动态光散射（DLS）和流式细胞术的结果证实EVs具有理想的形状、大小和表面标志物。新发病例和复发AML患者来源的EVs均显著降低了伊达比星诱导的U937细胞凋亡。药物外排泵基因分析显示，EVs在靶细胞中过表达 和 。这些发现提示EVs在通过诱导药物外排泵的表达介导AML患者获得性化疗耐药中具有新作用；然而，需要进一步研究以阐明由EVs介导的其他潜在耐药机制。
