Targeting microRNAs to eradicate leukemia stem cells

靶向 microRNA 根除白血病干细胞

基本信息

批准号：
9753734
负责人：
YA-HUEI KUO
金额：
$ 45.17万
依托单位：
BECKMAN RESEARCH INSTITUTE/CITY OF HOPE
依托单位国家：
美国
项目类别：
财政年份：
2017
资助国家：
美国
起止时间：
2017-08-01 至 2022-07-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9753734
关键词：
Acute Acute Myelocytic Leukemia Acute leukemia Allogenic Attenuated Biological Blood Bone Marrow Cause of Death Cell Compartmentation Cell Cycle Cell Maintenance Cell Maturation Cell Proliferation Cells Chronic Myeloid Leukemia Clinical Disease Dose Endothelial Cells Equilibrium Exposure to Gene Expression Profile Gene Targeting Genes Genetic Engineering Health Hematopoiesis Hematopoietic Hematopoietic stem cells Homeostasis Leukemic Cell Leukemic Hematopoietic Stem Cell Life Maintenance Malignant - descriptor Malignant Neoplasms Mediating Messenger RNA MicroRNAs Modeling Molecular Molecular Cytogenetics Molecular Target Myelogenous Outcome Output Patient-Focused Outcomes Pharmacodynamics Phosphorylation Site Phosphotransferases Plasma Population Property Protein Tyrosine Kinase Proteins Recurrence Recurrent disease Regulation Relapse Reporting Research Resistance Risk Role Sampling Schedule Stem cells Testing Toxic effect Translations Transplantation Treatment Efficacy Treatment outcome Tyrosine Kinase Inhibitor United States Untranslated RNA Up-Regulation aging population cell transformation chemotherapy chronic leukemia effective therapy exhaustion gene repression graft vs host disease graft vs leukemia effect improved in vivo inhibitor/antagonist leukemia leukemic stem cell leukemogenesis miRNA expression profiling mouse model novel outcome forecast pharmacodynamic model preclinical study prevent programs resistance mechanism self-renewal stem cell niche stem cell therapy stressor targeted agent targeted treatment therapeutic target therapy resistant treatment response

项目摘要

Leukemia stem cells (LSC) comprise subpopulations of cells in acute or chronic leukemia that have acquired “stem cell” properties including the ability to endure unlimited self-renewal, maintain aberrant clonal hematopoiesis and achieve quiescence upon exposure to chemotherapy or other bio-stressors thereby conferring resistance to antileukemia treatments. Currently available cell-cycle-dependent chemotherapy and other molecular targeting agents are unable to eliminate these LSCs. Thus new effective treatments to abrogate LSC are an unmet need. MicroRNAs (miRNAs) are short non-coding RNAs that regulate levels of multiple target proteins, thereby controlling a wide array of cellular programs. Among miRNAs that are deregulated in leukemia, higher expression of miR-126-3p (miR-126) is associated with LSC-gene expression signatures and poor outcome. Furthermore, higher levels of miR-126 controls quiescence both in normal hematopoietic stem cells (HSC) and LSC, but while attenuated miR-126 activity increases HSC hematopoietic output, it drives LSC to exhaustion. The central hypothesis of this proposal is that miR-126 is critical for the homeostasis of LSC and mediates LSC therapy resistance, thus represents a promising LSC-directed therapeutic target. The major objective of this application is to understand how miR-126 expression is aberrantly regulated in LSC and to develop an effective therapeutic approach to inhibit miR-126 in LSC, while sparing normal hematopoiesis. As a proof-of-principle, we will focus on targeting miR-126 in acute myeloid (AML) and chronic myeloid leukemia (CML), but similar principles could be expanded to other types of leukemia. We propose the following specific aims (SA): SA1. To dissect and overcome the molecular mechanisms of therapy resistance mediated by a newly discovered SPRED1/miR-126 autoregulatory loop in LSC. We will test that a tyrosine kinase (TK)-dependent SPRED1/miR-126 autoregulatory loop is operative in AML and CML, which mediate miR-126-dependent mechanisms of resistance to tyrosine kinase inhibitors (TKI). We will 1) assess the activity of SPRED1/miR-126 autoregulatory loop in distinct subtypes of AML; 2) define TK-dependent SPRED1 phosphorylation sites; 3) create leukemia mouse models to dissect the interplay of SPRED1/miR-126 autoregulatory loop with aberrantly active TK. SA2. To define the role of miR- 126 in maintaining a LSC niche within the bone marrow microenvironment. We will develop genetically engineered AML and CML models with conditional miR-126 deletion in LSC and endothelial cells (EC). We will determine 1) the contribution of miR-126 produced by LSC; 2) the contribution of miR-126 in the EC compartment; 3) whether deletion of miR-126 could enhance treatment-mediated elimination of LSC. SA3. To develop and optimize a synthetic inhibitor that targets miR-126 in LSC and the LSC niche. We will perform PK and PD analyses and preclinical studies to define the active dose/schedule of an antimiR-126 conjugated with CpG-oligodeoxynucleotide (ODN) for optimal targeted cell delivery.

白血病干细胞（LSC）急性或慢性白血病中细胞的完整亚群 “干细胞”特性，包括能够忍受无限自我更新，保持异常克隆的能力造血并在接触化学疗法或其他生物压力后达到静止赋予对抗血症治疗的抗药性。目前可用的细胞周期依赖性化学疗法和其他分子靶向剂无法消除这些LSC。这种新的有效治疗方法废除LSC是未满足的需求。 microRNA（miRNA）是调节水平的短非编码RNA 多种靶蛋白，从而控制了各种各样的细胞程序。在mirnas中 MiR-126-3p（miR-126）在白血病中受管制，与LSC-GENE表达有关签名和不良结果。此外，较高水平的miR-126在正常情况下控制静止造血干细胞（HSC）和LSC，但减弱的miR-126活性增加了HSC造血输出，它使LSC耗尽。该提议的核心假设是miR-126对于 LSC的稳态并介导LSC治疗耐药性，因此代表了承诺的LSC指导治疗靶标。该应用的主要目的是了解miR-126的表达方式在LSC中受到异常调节，并开发出一种有效的治疗方法来抑制LSC中的miR-126，而保留正常的造血。作为原理证明，我们将专注于针对急性髓样中的miR-126 （AML）和慢性髓样白血病（CML），但可以将类似的原则扩展到其他类型的白血病。我们提出以下特定目标（SA）：SA1。剖析和克服分子由新发现的SPRED1/miR-126自动调节介导的治疗抗性机制 LSC中的循环。我们将测试酪氨酸激酶（TK）依赖性SPRED1/miR-126自动调节环为 AML和CML的手术，介导miR-126依赖于酪氨酸激酶的miR-126依赖性机制抑制剂（TKI）。我们将1）评估SPRED1/MIR-126自动调节环的活性在不同的亚型中 AML; 2）定义依赖TK的SPRED1 PhotophoryLation位点； 3）创建白血病鼠标模型以剖析 SPRED1/miR-126自动调节环与异常活跃的TK的相互作用。 SA2。定义mir的作用 126在骨髓微环境中保持LSC生态位。我们将一般发展在LSC和内皮细胞（EC）中具有条件miR-126缺失的AML和CML模型。我们将确定1）LSC产生的miR-126的贡献； 2）miR-126在EC中的贡献车厢； 3）miR-126的缺失是否可以增强治疗介导的LSC消除。 SA3。到开发并优化了靶向LSC和LSC生态位中miR-126的合成抑制剂。我们将执行PK和PD分析和临床前研究，以定义Antimir-126的活动剂量/时间表与CpG-寡脱氧核苷酸（ODN）共轭，以获得最佳的靶向细胞递送。