Protein Phosphatase PP2A and DNA damage in cell fate decisions of acute myeloid leukemic cells

蛋白磷酸酶 PP2A 和 DNA 损伤在急性髓系白血病细胞命运决定中的作用

基本信息

批准号：
10019487
负责人：
Swagata Goswami
金额：
$ 3.8万
依托单位：
OHIO STATE UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2019
资助国家：
美国
起止时间：
2019-09-17 至 2021-04-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10019487
关键词：
ATR gene Acute Myelocytic Leukemia Acute Promyelocytic Leukemia Apoptosis Automobile Driving CD34 gene Cell Cycle Cell Cycle Arrest Cell Death Cell Differentiation process Cell Fate Control Cell Line Cell Survival Cells Cellular biology Cessation of life ChIP-seq Cytometry DNA Damage DNA Repair Data Differentiation Therapy Differentiation and Growth Flow Cytometry GADD45 protein GADD45A gene Genetic Genomics Goals Growth Hematologic Neoplasms Hematopoietic Hematopoietic Neoplasms Hematopoietic System Hematopoietic stem cells Homeostasis In Vitro Knock-out Knowledge Lead Leukemic Cell Link Literature Malignant Neoplasms Mediating Mind Molecular Mutation Myelogenous Oncogenes Oncogenic Pathogenesis Pathway interactions Patients Pharmaceutical Preparations Pharmacology Phase Phosphoric Monoester Hydrolases Phosphorylation Phosphotransferases Play Protein Serine/Threonine Phosphatase Protein phosphatase Proteins RNA Interference RUNX3 gene Research Research Project Grants Research Proposals Resistance Retinoblastoma Retinoblastoma Protein Role Safety Signal Transduction Small Interfering RNA Stress Survival Rate System Therapeutic Therapeutic Agents Tretinoin Tumor Suppressor Proteins Work acute myeloid leukemia cell base c-myc Genes cell injury chemotherapy clinical development design effective therapy genetic manipulation genome-wide in vivo inhibitor/antagonist insight interest kinase inhibitor knock-down leukemia leukemic stem cell mouse model novel novel strategies novel therapeutics oncoprotein p21 overexpression pre-clinical protein activation relapse patients repaired research clinical testing response single cell analysis skills stem cell population therapeutic candidate tool transcription factor transcriptome sequencing

项目摘要

PROJECT SUMMARY Acute Myeloid Leukemia (AML) is a cancer characterized by a co-operative block in hematopoietic maturation and proliferative advantage. It is near incurable, with a 5-year survival rate of only 25% and median survival <1year in patients over 65 years. Current chemotherapy is very poorly tolerated and majority of patients relapse. Overcoming the differentiation block is a promising therapeutic avenue, however is majorly lacking for AML subtypes without a known driver oncogene. Our study examines new pathways to target the two major aspects of leukemic cell survival, the differentiation block and increased proliferative ability, that can prove effective across multiple subtypes. Reversible protein phosphorylation controls many aspects of such cell fate decisions, and an imbalance in the normal activities of kinases and phosphatases contribute to pathogenesis of AML. However, while the aberrant activation of kinases, frequent in AML, is well studied and exploited for therapeutic purposes, inactivation of phosphatases, also prevalent in AML, is often overlooked. This proposal focuses on the serine threonine phosphatase tumor suppressor Protein Phosphatase 2A (PP2A) and its role in influencing proliferation vs differentiation decisions in AML. For the F99 phase, we identified a novel role for PP2A in driving myeloid differentiation and cell cycle arrest in AML. Based on our preliminary data, our overall hypothesis is that PP2A drives differentiation and cell cycle arrest through the cell cycle regulator p21. We specifically seek to establish the mechanism of PP2A mediated p21 induction, and the role of potential downstream factors Retinoblastoma protein and CEBP proteins in driving differentiation in AML using genetic overexpression and knockdown systems, CHIP-Seq and single cell analysis using Mass Cytometry. The K00 phase focuses on identification of factors mediating DNA damage induced differentiation. While DNA damage has been shown to induce differentiation in AML and hematopoietic progenitors, the molecular mechanism is poorly understood. Interestingly, DNA repair machinery including ATM and ATR serine threonine kinases protect leukemic cells from damage induced differentiation and are hyperactivated in AML. This raises the possibility that inhibiting DNA repair can promote genomic stress induced differentiation. My hypothesis for the K00 phase is that PP2A can antagonize DNA repair kinases and promote differentiation in response to DNA damage in AML. I will establish the role of PP2A and other potential candidates identified from preliminary data and literature such as GADD45 proteins and p21 in DNA damage induced differentiation in AML using genetic and pharmacological activation of PP2A, overexpression, knockdown and knockout of GADD45 as well as global in-vitro and in-vivo RNAi and genome wide CRISPER screen analyses. Successful completion of this proposal will yield new insight into cellular pathways capable of inducing growth arrest and terminal differentiation of maturation blocked cancers such as AML.

项目概要急性髓系白血病 (AML) 是一种以造血成熟协同受阻为特征的癌症和增殖优势。它几乎无法治愈，5年生存率仅为25%，中位生存率 65 岁以上患者<1 年。目前的化疗耐受性非常差，大多数患者会复发。克服分化障碍是一种有前景的治疗途径，但 AML 却缺乏这种途径没有已知驱动癌基因的亚型。我们的研究探讨了针对两个主要方面的新途径白血病细胞存活、分化阻断和增殖能力增强，这可以证明是有效的跨越多个亚型。可逆的蛋白质磷酸化控制着细胞命运决定的许多方面，以及激酶和磷酸酶的正常活性有助于 AML 的发病机制。然而，尽管异常 AML 中常见的激酶激活已被充分研究并用于治疗目的，磷酸酶在 AML 中也很常见，但常常被忽视。该提案重点关注丝氨酸苏氨酸磷酸酶抑癌蛋白磷酸酶 2A (PP2A) 及其在影响增殖与增殖中的作用 AML 中的差异化决策。对于 F99 阶段，我们确定了 PP2A 在驱动骨髓细胞中的新作用 AML 中的分化和细胞周期停滞。根据我们的初步数据，我们的总体假设是 PP2A 通过细胞周期调节因子 p21 驱动分化和细胞周期停滞。我们特别寻求建立 PP2A 介导 p21 诱导的机制以及潜在下游因素视网膜母细胞瘤的作用蛋白和 CEBP 蛋白利用基因过表达和敲低驱动 AML 分化系统、CHIP-Seq 和使用质谱细胞术的单细胞分析。 K00 阶段的重点是鉴定介导 DNA 损伤诱导分化的因素。而DNA 损伤已被证明可诱导 AML 和造血祖细胞的分化，这是分子机制尚不清楚。有趣的是，DNA修复机制包括ATM和ATR丝氨酸苏氨酸激酶保护白血病细胞免受损伤诱导的分化，并且在 AML 中过度激活。这引发了抑制 DNA 修复可以促进基因组应激诱导的分化。我的假设 K00期是PP2A可以拮抗DNA修复激酶并响应DNA促进分化 AML 中的损害。我将确定 PP2A 的角色以及从初步数据中确定的其他潜在候选者以及文献，例如 GADD45 蛋白和 p21 在 DNA 损伤中使用遗传基因诱导 AML 分化 PP2A 的药理激活、GADD45 的过表达、敲低和敲除以及全局体外和体内 RNAi 以及全基因组 CRISPER 筛选分析。顺利完成本提案将产生对能够诱导生长停滞和终末分化的细胞途径的新见解成熟可以阻止 AML 等癌症。