Pathogenic Mechanisms of CSF3R Mutations in Leukemia

描述（由申请人提供）：集落刺激因子3受体（CSF3R）被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）和非典型慢性髓性白血病（aCML）患者中发现了CSF3R突变。这些突变中最常见的是T618I，它通过失去o链糖基化位点来促进与配体无关的受体二聚化。该突变还高度激活了Janus Activated Kinase （JAK）信号通路，JAK激酶抑制剂在小鼠模型和该突变患者中有效。在Aim 1中，我们将研究o -链糖基化对正常CSF3R受体功能的调节。SETBP1的致癌点突变与CSF3R突变联合发生，导致这些疾病预后不良。在Aim 2中，我们将对患者样本和我们的CSF3R T618I小鼠模型进行测序，以确定有助于白血病发生的新遗传驱动因素，并通过单细胞RNA测序研究CSF3R和SETBP1突变的获取顺序。在Aim 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。这些目标将为正常CSF3R功能的调控、CNL/aCML的分子进化以及多种基因驱动表达的预后后果提供基本见解。我的目标是成为一名成功的独立研究者和血液恶性肿瘤分子表征和新治疗靶点鉴定领域的领导者。在指导阶段，我将继续接受Brian Druker博士的优秀指导，他是靶向癌症治疗的先驱，也是Knight癌症研究所的负责人。在我的顾问委员会成员，加州大学伯克利分校的Carolyn Bertozzi博士的指导下，我将在蛋白质糖基化领域接受额外的培训，在Fred Hutchinson癌症研究中心的Jerald Radich博士的指导下，我还将接受单细胞分析方法方面的培训。和Bertozzi医生和Radich医生一起工作会让我在我的机构之外扩展我的训练。在癌细胞信号和小鼠模型专家Jeffrey Tyner博士和Shannon McWeeney博士的指导下，拟议的研究也将得到加强，Shannon McWeeney博士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协助我顺利过渡到一个独立的教师职位。

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.