Elucidating the molecular mechanism of Daple- FLT3 and Daple-PDGFRB gene fusion in blood cancers

阐明Daple-FLT3和Daple-PDGFRB基因融合在血癌中的分子机制

基本信息

批准号：
10666603
负责人：
Jason Ear
金额：
$ 18.38万
依托单位：
CALIFORNIA STATE POLY U POMONA
依托单位国家：
美国
项目类别：
财政年份：
2022
资助国家：
美国
起止时间：
2022-07-15 至 2026-06-30
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10666603
关键词：
Address Affect Award BAY 54-9085 Biochemical Biological Assay Blood Vessels Cell Count Cell Line Cells Centrosome Chromosomal Rearrangement Chromosomes Coiled-Coil Domain Combined Modality Therapy Cultured Cells Dimerization Disease model Dominant-Negative Mutation Drug resistance Embryo Embryonic Development Exposure to FLT3 gene Fluorescence Resonance Energy Transfer GTP-Binding Proteins Gene Activation Gene Fusion Genes Health Hematopoietic Hematopoietic Neoplasms Heterotrimeric GTP-Binding Proteins Homeostasis Human Imatinib In Vitro Lead Leukemic Cell Life Ligand Binding Domain Liquid substance Lymphocyte Lymphoma cell MAPK3 gene MEKs Malignant Neoplasms Messenger RNA Microscopy Modality Modeling Molecular Monitor Mus Mutation Myeloproliferative disease Nature Oncogenic Organism PDGFRB gene Pathway interactions Patients Pharmaceutical Preparations Phenotype Phosphotransferases Play Population Proteins Proto-Oncogene Proteins c-akt Ras/Raf Receptor Protein-Tyrosine Kinases Receptor Signaling Regulation Resistance Role Scaffolding Protein Signal Pathway Signal Transduction Signal Transduction Pathway Signaling Molecule Signaling Protein Solid Neoplasm Students Testing Therapeutic Therapeutic Intervention Time Training Tyrosine Kinase Domain Tyrosine Kinase Inhibitor Up-Regulation WNT Signaling Pathway Western Blotting Work Zebrafish biological research cancer cell cancer therapy career cell growth dosage embryo tissue fluorescence imaging gene product in vivo Model inhibitor therapy insight leukemia mutant new therapeutic target novel novel therapeutics overexpression patient response patient subsets protein oligomer protein protein interaction receptor response side effect therapeutic evaluation therapeutic protein tool transcriptomics tumor tumor progression

项目摘要

PROJECT SUMMARY/ABSTRACT: Receptor tyrosine kinases (RTKs) are a major class of cell signaling receptors and they play major roles in cancer progression. In leukemia, and many cancers, aberrant activation of the RAS-RAF-MEK-ERK signal transduction pathway is often observed. Various RTK mutations, such as those found on PDGFRB and FLT3, are found in leukemia patients and often lead to hyperactivation of the kinase domain. This activation causes the subsequent increase in the RAS-RAF-MEK-ERK signaling pathway. Because the cancer is driven by kinase domain activation, many patients are responsive to tyrosine kinase inhibitor (TKI) treatment such as imatinib and sorafenib. However, in a subset of patients, they become unresponsive to TKIs over time due to a resistance in the cancer cells. One mechanism by which cancer cells can acquire resistance is through gaining a secondary mutation in the kinase domain that makes the kinase insensitive to the TKI. In response, patients are often given higher drug dosage or an approach to target multiple pathways simultaneously using combination therapy is taken. These approaches are often impractical due to cumulative side effects that may be life-threatening. Thus, further insights into the inner workings of cancer cells and mutations that lead to aggressive cancer phenotypes are essential to identifying new therapeutic targets, especially, those on which multiple cancer-fueling signaling pathways may converge. Daple/CCDC88C is scaffold protein that serves as a convergence point for three major signaling pathways in a cell: Wnts, G-proteins, and RTKs. Because protein scaffolds can serve as central hubs integrating cellular signaling, this raises the possibility of exploiting these proteins for therapeutic intervention. Several gene fusion between Daple and PDGFRB or FLT3 have been found in cases of myeloproliferative disorders and leukemias. The exact mechanism by which these gene fusions lead to constitutive activation of the kinase domain remains to be tested and whether regions on Daple that is involved in the gene fusion can be leveraged for therapy remains a mystery. Finally, because these mutations are rare, generating an in vivo model for therapeutic testing in mice is often seen as unpractical. This proposal seeks to address these questions and problems. Specifically, it seeks to understand how the Daple gene fusion affects hematopoietic cell expansion using cell-based models and zebrafish. Also planned in this proposal is to expose how the coiled-coil domain of the Daple-PDGFRB or Daple-FLT3 gene fusion affects protein subcellular localization and to determine if it is responsible for the dimerization and activation of the kinase domain in cells. The strategy that will be employed to target the dimerization point may also serve as a therapeutic strategy. Overall, these studies will give novel insights into how Daple associated mutations affect leukemia cell signaling and growth and it will also establish whether targeting this protein scaffold can be leveraged for cancer therapy.

项目概要/摘要：受体酪氨酸激酶 (RTK) 是一类主要的细胞信号传导受体，在癌症中发挥着重要作用进展。在白血病和许多癌症中，RAS-RAF-MEK-ERK 信号转导的异常激活经常观察到路径。各种 RTK 突变，例如在 PDGFRB 和 FLT3 上发现的突变，被发现于白血病患者经常会导致激酶结构域过度激活。此激活会导致后续 RAS-RAF-MEK-ERK 信号通路增加。因为癌症是由激酶结构域驱动的激活，许多患者对酪氨酸激酶抑制剂（TKI）治疗有反应，例如伊马替尼和索拉非尼。然而，在一部分患者中，随着时间的推移，由于 TKI 的耐药性，他们对 TKI 失去了反应。癌细胞。癌细胞获得耐药性的一种机制是通过获得继发性激酶结构域发生突变，使激酶对 TKI 不敏感。作为回应，患者经常被给予更高的药物剂量或使用联合疗法同时靶向多个途径的方法是采取。这些方法通常不切实际，因为累积的副作用可能会危及生命。因此，进一步了解癌细胞的内部运作和导致侵袭性癌症表型的突变对于确定新的治疗靶点至关重要，特别是那些存在多种癌症促进信号传导的靶点路径可能会汇聚。 Daple/CCDC88C 是支架蛋白，是三个主要蛋白的汇聚点细胞内的信号传导途径：Wnt、G 蛋白和 RTK。因为蛋白质支架可以充当中心枢纽整合细胞信号传导，这提高了利用这些蛋白质进行治疗干预的可能性。在骨髓增生性疾病病例中发现了 Daple 与 PDGFRB 或 FLT3 之间的多种基因融合疾病和白血病。这些基因融合导致组成型激活的确切机制激酶结构域仍有待测试，Daple 上参与基因融合的区域是否可以被用于治疗仍然是一个谜。最后，由于这些突变很少见，因此生成了体内模型在小鼠身上进行治疗测试通常被认为是不切实际的。本提案旨在解决这些问题并问题。具体来说，它试图了解 Daple 基因融合如何影响造血细胞扩增使用基于细胞的模型和斑马鱼。该提案还计划揭示卷绕线圈域如何 Daple-PDGFRB 或 Daple-FLT3 基因融合影响蛋白质亚细胞定位并确定其是否负责细胞中激酶结构域的二聚化和激活。将采用的策略以二聚化点为目标也可以作为一种治疗策略。总的来说，这些研究将提供新颖的深入了解 Daple 相关突变如何影响白血病细胞信号传导和生长，还将建立靶向这种蛋白质支架是否可以用于癌症治疗。