Pathogenic Mechanisms of CSF3R Mutations in Leukemia

描述(申请人提供)：集落刺激因子3受体(CSF3R)由CSF3(又名GCSF)激活，CSF3是一种促进中性粒细胞增殖和分化的细胞因子。我们最近在59%的慢性中性粒细胞白血病(CNL)和不典型慢性粒细胞白血病(ACML)患者中发现了CSF3R突变。这些突变中最常见的是T618I，它通过丢失O-连接的糖基化位点来促进配体非依赖性受体二聚化。这种突变还高度激活了Janus激活的激酶(JAK)信号通路，JAK激酶抑制剂在小鼠模型和患有这种突变的患者中是有效的。在目标1中，我们将研究O-连接糖基化对正常CSF3R受体功能的调节。在这些疾病中，SETBP1致癌点突变与CSF3R突变同时发生，预后不良。在目标2中，我们将对患者样本和我们的CSF3R T618I小鼠模型进行测序，以确定导致白血病发生的新的遗传驱动因素，并通过单细胞RNA测序调查CSF3R和SETBP1突变的获得顺序。在目标3中，我们将确定CSF3R和SETBP1突变对癌症进展和激酶抑制剂敏感性的功能后果。这些目的将为了解正常CSF3R功能的调节、CNL/aCML的分子进化以及表达多种遗传驱动因素的预后后果提供基本的见解。我的目标是成为一名成功的独立研究人员，并在恶性血液病的分子表征和新的治疗靶点识别领域中处于领先地位。在指导阶段，我将继续得到布莱恩·德鲁克博士的极好指导，他是靶向癌症治疗的先驱，也是奈特癌症研究所的领导人。在我的咨询委员会成员加州大学伯克利分校的Carolyn Bertozzi博士的指导下，我将接受蛋白质糖基化领域的额外培训，并在弗雷德·哈钦森癌症研究中心的Jerald Radich博士的指导下，接受单细胞分析方法的培训。与Bertozzi博士和Radich博士合作将使我能够将我的培训扩展到我的机构之外。拟议中的研究还将得到癌细胞信号和老鼠模型专家杰弗里·泰纳博士和香农·麦克维尼博士的指导，后者将指导我对测序数据进行生物信息学分析。此外，德鲁克博士和我的顾问团队将帮助我顺利过渡到独立教职。

DESCRIPTION (provided by applicant): Colony Stimulating Factor 3 Receptor (CSF3R) is activated by CSF3 (aka GCSF), the cytokine that promotes neutrophil proliferation and differentiation. We have recently identified CSF3R mutations in 59% of patients with chronic neutrophilic leukemia (CNL) and atypical chronic myeloid leukemia (aCML). The most common of these mutations, T618I, promotes ligand-independent receptor dimerization through loss of an O-linked glycosylation site. This mutation also highly activates the Janus Activated Kinase (JAK) signaling pathway and JAK kinase inhibitors were effective in mouse models and a patient with this mutation. In Aim 1 we will investigate the regulation of normal CSF3R receptor function by O-linked glycosylation. Oncogenic point mutations in SETBP1 occur in combination with CSF3R mutations, and confer poor prognosis in these diseases. In Aim 2 we will sequence patient samples and our CSF3R T618I mouse model to identify novel genetic drivers that contribute to leukemogenesis and also investigate the order of acquisition of CSF3R and SETBP1 mutations by single cell RNA sequencing. In Aim 3 we will determine the functional consequences of having both CSF3R and SETBP1 mutations for cancer progression and kinase inhibitor sensitivity. These Aims will provide fundamental insight into the regulation of normal CSF3R function, the molecular evolution of CNL/aCML, and the prognostic consequence of having multiple genetic drivers expressed. My goal is to become a successful independent investigator and a leader in the field of molecular characterization of hematologic malignancies and identification of novel therapeutic targets. During the mentored phase I will continue to receive excellent mentorship from Dr. Brian Druker, a pioneer of targeted cancer therapy and leader of the Knight Cancer Institute. I will undertake additional training in the fiel of protein-glycosylation, with guidance from my advisory committee member, Dr. Carolyn Bertozzi at UC Berkeley, and also in single cell analysis methods, guided by Dr. Jerald Radich at the Fred Hutchinson Cancer Research Center. Working with Dr. Bertozzi and Dr. Radich will allow me to expand my training outside of my institution. The proposed research will also be enhanced by guidance from Dr. Jeffrey Tyner, an expert in cancer cell signaling and mouse models, and Dr. Shannon McWeeney who will guide me in bioinformatics analysis of sequencing data. Additionally, Dr. Druker and my advisory team will assist me in navigating the transition to an independent faculty position.