Mechanisms and targeting of aberrant Gas activation in myeloid neoplasms

骨髓肿瘤中异常气体​​激活的机制和靶向

• 批准号: 10659809
• 负责人: Eirini Papapetrou
• 金额: $ 67.09万
• 依托单位: ICAHN SCHOOL OF MEDICINE AT MOUNT SINAI
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-04-01 至 2028-03-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10659809
• 关键词: Acute Myelocytic Leukemia; Address; Apoptosis; Biochemical; Biochemical Genetics; Biological Assay; Bone Marrow; CRISPR/Cas technology; Cell physiology; Cells; Clinical; Clinical Trials; Clustered Regularly Interspaced Short Palindromic Repeats; Cyclic Peptides; Data; Dependence; Development; Disease; Dysmyelopoietic Syndromes; FLT3 gene; Frequencies; Future; G-Protein-Coupled Receptors; GNAS gene; GTP-Binding Protein alpha Subunits, Gs; GTP-Binding Proteins; Gases; Gene Mutation; Genes; Genetic; Genetic Transcription; Goals; Hematopoietic; Hematopoietic stem cells; Human; In Vitro; Inflammatory; Knock-out; Malignant Neoplasms; Mediating; Mutate; Mutation; Myeloproliferative disease; Oncogenic; Patients; Pharmaceutical Preparations; Phase; Phenotype; Population Genetics; Process; Production; Prognosis; Protein Array; Protein Isoforms; RNA Binding; RNA Splicing; RNA-Binding Proteins; Role; SRSF2 gene; Sampling; Secondary acute myeloid leukemia; Secondary to; Signal Pathway; Signal Transduction; Signaling Molecule; Somatic Mutation; Spliced Genes; System; Testing; Therapeutic; Therapeutic Intervention; Tissue Banks; Transcript; Work; Xenograft procedure; acute myeloid leukemia cell; drug development; effective therapy; genetic approach; induced pluripotent stem cell; inhibitor; leukemic transformation; mRNA Precursor; mutant; new therapeutic target; novel; novel therapeutics; pharmacologic; programs; research clinical testing; stem cell model; therapeutic target; transcriptome sequencing; transcriptomics

PROJECT SUMMARY/ABSTRACT Myelodysplastic syndromes (MDS) are myeloid neoplasms with dismal prognosis, frequent progression to acute myeloid leukemia (AML) and no effective treatment. A decade ago, a development with transformative potential for this disease was the discovery that more than half of MDS patients have somatic mutations in genes encoding splicing factors (SFs, i.e. RNA binding proteins that regulate pre-mRNA splicing). While the high frequency and early occurrence during the disease course of SF mutations rendered them promising targets, efforts to therapeutically leverage this through splicing modulator drugs did not show promise in clinical testing and the drug development pipeline for these targets, and for MDS in general, is currently nearly empty. We developed genetically faithful human induced pluripotent stem cell (iPSC) models of SF-mutated MDS using CRISPR gene editing and performed integrative analyses of splicing (RNA-Seq) and RNA binding (eCLIP) to search for mis-spliced transcripts that are direct common targets of two of the main SF mutations (SRSF2 P95L and the U2AF1 S34F). We found that both mutant SRSF2 and mutant U2AF1 cause altered splicing of the gene GNAS, promoting the production of a longer isoform (GNAS-L), which in turn produces a longer form of the alpha subunit of the stimulatory G protein, G⍺s (G⍺s-L). G proteins are key signaling molecules involved in many important signaling pathways and cell functions, including oncogenic processes. Our preliminary data using functional, biochemical and population genetics approaches support a critical role for the long form of G⍺s (G⍺s-L) as an MDS driver and reveal a new mechanism by which SF mutations drive MDS that opens a completely novel and unexplored therapeutic avenue for MDS, AML and other cancers with SF gene mutations. The goal of this proposal is to investigate G⍺s as a therapeutic target for MDS and identify opportunities for therapeutic interventions that inhibit signaling by G⍺s-L. Specifically, we propose to: (1) Evaluate the effects of direct degradation (through a dTAG) or inhibition (by novel cyclic peptides) of G⍺s in splicing factor (SF)-mutated MDS and AML hematopoietic cells (primary and iPSC-derived) using recently developed iPSC-based models of MDS-to-sAML progression and longitudinal bone marrow samples from MDS patients who progressed to AML; (2) Characterize and target cell signaling downstream of Gs-L through candidate and unbiased approaches (Reverse Phase Protein Array, CyTOF, transcriptomics); and (3) Identify the G-protein coupled receptors (GPCRs) involved in Gs-L activation in SF-mutated MDS and AML through focused CRISPR KO screens. This study can establish a novel therapeutic target that may transform the treatment of MDS, AML and possibly other cancers.

项目概要/摘要 骨髓增生异常综合征 (MDS) 是一种预后不良、进展频繁的骨髓肿瘤 十年前，急性髓系白血病（AML）尚无有效治疗方法。 这种疾病的潜在可能性是发现超过一半的 MDS 患者具有体细胞突变 编码剪接因子的基因（SF，即调节前 mRNA 剪接的 RNA 结合蛋白）。 SF 突变在疾病过程中的高频率和早期发生使其具有前景 目标，通过剪接调节剂药物来治疗利用这一目标的努力在临床上并未显示出希望 针对这些靶标以及整个 MDS 的测试和药物开发渠道目前几乎是空的。 我们开发了遗传上忠实的 SF 突变人类诱导多能干细胞 (iPSC) 模型 MDS 使用 CRISPR 基因编辑并对剪接 (RNA-Seq) 和 RNA 结合进行综合分析 (eCLIP) 搜索错误剪接的转录本，这些转录本是两个主要 SF 突变的直接共同目标 （SRSF2 P95L 和 U2AF1 S34F）我们发现突变体 SRSF2 和突变体 U2AF1 都会引起改变。 基因 GNAS 的剪接，促进更长亚型（GNAS-L）的产生，进而产生 刺激性 G 蛋白 α 亚基的较长形式 G⍺s (G⍺s-L) 是关键信号传导。 分子参与许多重要的信号传导途径和细胞功能，包括致癌过程。 我们使用功能、生化和群体遗传学方法获得的初步数据支持了关键作用 将长形式的 G⍺s (G⍺s-L) 作为 MDS 驱动程序，并揭示了 SF 突变驱动的新机制 MDS 为 MDS、AML 和其他癌症开辟了一条全新且未经探索的治疗途径 SF基因突变。 该提案的目标是研究 G⍺s 作为 MDS 的治疗靶点并确定 具体来说，我们建议：（1）进行抑制 G⍺s-L 信号传导的治疗干预。 评估 G⍺ 的直接降解（通过 dTAG）或抑制（通过新型环肽）的效果 最近使用剪接因子 (SF) 突变的 MDS 和 AML 造血细胞（原代和 iPSC 衍生的） 开发了基于 iPSC 的 MDS 至 sAML 进展模型以及来自 MDS 的纵向骨髓样本 进展为 AML 的患者 (2) 通过以下方式表征和靶向 Gαs-L 下游的细胞信号转导 候选且公正的方法（反相蛋白阵列、CyTOF、转录组学）；以及 (3) 识别 G 蛋白偶联受体 (GPCR) 通过 SF 突变的 MDS 和 AML 参与 Gα-L 激活 重点 CRISPR KO 筛选。 这项研究可以建立一个新的治疗靶点，可能会改变 MDS、AML 和 可能还有其他癌症。