Project 3 - Novel Therapies for Spliceosomal-Mutant MDS.

项目 3 - 剪接体突变型 MDS 的新疗法。

基本信息

批准号：
10194402
负责人：
Matthew J Walter
金额：
$ 27.4万
依托单位：
WASHINGTON UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2013
资助国家：
美国
起止时间：
2013-09-03 至 2023-06-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10194402
关键词：
AML/MDS Acute Myelocytic Leukemia Address Alternative Splicing Aspirate substance Bioavailable Biology Bone Marrow CRISPR screen Cell Death Cell Line Cell model Cells Chronic Myelomonocytic Leukemia Clinical Clinical Trials Combined Modality Therapy Complex Correlative Study DNA DNA Damage DNA damage checkpoint Data Development Disease Progression Dose Drug Combinations Drug resistance Dysmyelopoietic Syndromes Enrollment Erythropoietin Excision Future Genes Genetic Genetic Markers Genetically Engineered Mouse Genomic Instability Goals Hematopoietic Hybrids In Vitro Link Measures Mediating Metabolic Pathway Modeling Molecular Mutate Mutation Myeloproliferative disease Natural Killer Cells Oral Pathway interactions Patients Pharmaceutical Preparations Pharmacodynamics Pharmacology Pharmacotherapy Phase Phase I/II Trial Phase II Clinical Trials Pre-Clinical Model Prognosis Protein-Serine-Threonine Kinases RNA RNA Splicing Recurrence Refractory Relapse Reporting Resistance Resolution Risk Running SRSF2 gene Safety Salvage Therapy Sampling Signal Pathway Signal Transduction Single-Stranded DNA Specialized Program of Research Excellence Spliceosomes Structure Testing Toxic effect Transfusion base cell type clinical development cytotoxic drug sensitivity efficacy testing exome sequencing first-in-human functional status genetic testing genome-wide high risk improved in vivo in vivo Model inhibitor/antagonist leukemia mRNA Precursor mouse model mutant novel novel drug combination novel therapeutic intervention novel therapeutics phase II trial pre-clinical preclinical study predicting response primary endpoint response secondary endpoint small molecule standard of care targeted treatment transcriptome sequencing

项目摘要

Project Summary Current therapies for myelodysplastic syndromes (MDS) and acute myeloid leukemia (AML) are unsatisfactory. We and others discovered that components of the pre-mRNA splicing complex are recurrently mutated in patients with MDS and AML and induce alterations in RNA splicing. Small molecule modulators of this complex (i.e., splicing modulators) have been developed by our collaborators and others. We recently reported that expression of mutant splicing factors or pharmacologic perturbation of splicing with splicing modulators increase the abundance of R loops, which are structures containing DNA:RNA hybrids and displaced single-strand DNA. R loops trigger an ATR-dependent DNA damage checkpoint response that mediates resolution of the R loop to protect cells from genomic instability and cell death. Our preliminary preclinical data suggest that spliceosome mutant cells are more sensitive to ATR inhibition than wild-type cells. We hypothesize that splicing factor mutations create a vulnerability to ATR inhibition (ATRi) that can be exploited for the development of novel therapeutic strategies when used alone or in combination with splicing modulator drugs. We will test this hypothesis in a phase II clinical trial of an ATRi in patients with myeloid malignancies and using well-defined in vitro and in vivo models. In Specific Aim 1, we will conduct a phase II trial of ATR inhibition in relapsed/refractory MDS and chronic myelomonocytic leukemia (CMML) and determine the molecular basis of sensitivity and resistance to this novel therapy. We predict that patients with spliceosome mutations will have an increased response rate to ATRi compared to patients without a splicing factor mutation. Correlative studies will assess pharmacodynamic endpoints and examine the mechanisms of drug sensitivity and resistance, if it occurs. In Specific Aim 2, we will test the efficacy of ATRi in combination with splicing modulators in models of spliceosome-mutant MDS. Preliminary evidence suggests that exposure of splicing factor mutant expressing hematopoietic cells to small molecule modulators of the spliceosome exacerbates R loop formation and increases sensitivity of cells to ATRi. We will use genetically-defined cellular and mouse models exposed in vitro and in vivo to a variety of spliceosome modulators alone or in combination with ATRi. Finally, we will perform a genome-wide CRISPR/Cas9 screen to identify genes and pathways that could sensitize spliceosome-mutant cells to the cytotoxic effects of ATRi that could be pursued in future clinical trials. This project addresses SPORE translational endpoints by conducting a first in human clinical trial of an ATRi in patients with myeloid malignancies. We will identify genetic biomarkers that are predictive of response to ATRi and establish the preclinical data necessary to nominate combination therapies that could be used to develop the first novel:novel combination of drugs for the treatment of MDS and AML with splicing factor mutations.

项目概要目前治疗骨髓增生异常综合征（MDS）和急性髓性白血病（AML）的方法并不令人满意。我们和其他人发现前 mRNA 剪接复合物的成分在 MDS 和 AML 患者并诱导 RNA 剪接改变。这种小分子调节剂我们的合作者和其他人开发了复合体（即剪接调制器）。我们最近报道了突变剪接因子的表达或剪接的药理学扰动调节剂增加 R 环的丰度，R 环是含有 DNA:RNA 杂合体的结构置换单链DNA。 R 环触发 ATR 依赖性 DNA 损伤检查点反应介导 R 环的解析，以保护细胞免受基因组不稳定和细胞死亡的影响。我们的初步临床前数据表明，剪接体突变细胞比野生型细胞对 ATR 抑制更敏感。我们假设剪接因子突变会导致 ATR 抑制 (ATRi) 的脆弱性，这可能是单独使用或与剪接组合使用时，可用于开发新型治疗策略调节药物。我们将在骨髓性骨髓瘤患者中进行 ATRi 的 II 期临床试验来检验这一假设恶性肿瘤并使用明确的体外和体内模型。在具体目标 1 中，我们将进行第二阶段 ATR 抑制治疗复发/难治性 MDS 和慢性粒单核细胞白血病 (CMML) 的试验以及确定对这种新疗法的敏感性和耐药性的分子基础。我们预测患者与没有剪接的患者相比，剪接体突变的患者对 ATRi 的反应率更高因子突变。相关研究将评估药效学终点并检查其机制药物敏感性和耐药性（如果发生）。在具体目标2中，我们将测试ATRi组合的功效在剪接体突变MDS模型中使用剪接调节剂。初步证据表明，暴露表达造血细胞的剪接因子突变体与剪接体小分子调节剂的关系加剧 R 环形成并增加细胞对 ATRi 的敏感性。我们将使用基因定义的在体外和体内单独或在体内暴露于各种剪接体调节剂的细胞和小鼠模型与 ATRi 组合。最后，我们将进行全基因组 CRISPR/Cas9 筛选来识别基因和可以使剪接体突变细胞对 ATRi 的细胞毒性作用敏感的途径在未来的临床试验中。该项目通过在人类中进行首次研究来解决 SPORE 翻译终点问题 ATRi 在骨髓恶性肿瘤患者中的临床试验。我们将识别遗传生物标志物预测对 ATRi 的反应并建立提名联合疗法所需的临床前数据可用于开发第一个新型药物：用于治疗 MDS 和 AML 的新型药物组合剪接因子突变。