The role of the histone chaperone Chaf1b in sustaining the Hoxa9-driven AML differentiation block

组蛋白伴侣 Chaf1b 在维持 Hoxa9 驱动的 AML 分化阻断中的作用

• 批准号: 9295511
• 负责人: Mario Andres Blanco
• 金额: $ 19.2万
• 依托单位: UNIVERSITY OF PENNSYLVANIA
• 依托单位国家: 美国
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-09-01 至 2021-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9295511
• 关键词: ATAC-seq; Acute Myelocytic Leukemia; Affect; Animal Model; Automobile Driving; Bachelor' s Degree; Biochemical; Biochemistry; Blast Cell; Blood; Boston; Breast cancer metastasis; Cancer Biology; Cancer Etiology; Cell Cycle Arrest; Cell Differentiation process; Cell physiology; Cells; Cessation of life; ChIP-seq; Chromatin; Collaborations; Complex; Computational Biology; Consultations; DNA; DNA Modification Process; Data; Development; Differentiated Gene; Differentiation Therapy; Doctor of Philosophy; Epigenetic Process; Faculty; Fellowship; Foundations; Funding; Gene Expression; Genetic; Genetic Screening; Genetic Transcription; Genomics; Goals; Grant; Hematologic Neoplasms; Hematopoiesis; Hematopoietic Neoplasms; Hematopoietic stem cells; Histones; Interview; Journals; Knockout Mice; Laboratories; MLL-AF9; Malignant Neoplasms; Malignant neoplasm of brain; Mediating; Methodology; Modeling; Molecular; Molecular Biology; Molecular Chaperones; Mus; Myelogenous; Nature; Neoadjuvant Therapy; Nucleosomes; Paper; Pathology; Patients; Pediatric Hospitals; Pennsylvania; Phase; Physiological; Plant Roots; Positioning Attribute; Postdoctoral Fellow; Process; Proteins; Publishing; RNA; RNA immunoprecipitation sequencing; Relapse; Reporting; Research; Research Personnel; Role; Schools; Scientist; Societies; Solid Neoplasm; Stimulus; Testing; Therapeutic; Training; Transgenes; Tretinoin; United States National Institutes of Health; Universities; Untranslated RNA; Vision; Visit; Work; Writing; Yang; anticancer research; base; blocking factor; burden of illness; career; cell type; cellular pathology; chemotherapy; chromatin remodeling; clinically relevant; design; epigenetic regulation; epigenomics; in vivo; interest; leukemia/lymphoma; medical schools; member; mouse model; novel; programs; recruit; response; screening; small hairpin RNA; stemness; tenure track; therapeutic candidate; therapeutic target; transcription factor; transcriptome sequencing; transcriptomics

Project Summary/Abstract I received my undergraduate degree from Cornell University, my PhD in molecular biology from Princeton University, and am currently a postdoctoral researcher and Special Fellow of the Leukemia and Lymphoma Society at Harvard Medical School and Boston Children's Hospital. After studying the molecular basis of breast cancer metastasis in graduate school, I transitioned to the field of epigenetics in the laboratory of Yang Shi for my postdoc. I have received extensive experimental and scholarly training in my postdoc. I learned the rigors of basic chromatin biochemistry in my first postdoctoral project, and recently published a co-first author paper based on this work. This study was featured as the cover article in the journal Cell and reported the identification of a novel metazoan epigenetic DNA modification, N6-methyladenine (6mA). My scholarly training has involved extensive scientific writing and has enabled me to write three successful postdoc fellowship applications (from the NIH, ACS, and LLS), two successful grants for Dr. Shi based on my work (from the Samuel Waxman Cancer Research Foundation and the Harvard Epigenetics Initiative), and one recently published review paper as a co-author in the journal Nature Reviews Molecular Biology. My current postdoctoral research merges my background in cancer biology with my recent training in chromatin biochemistry and focuses on the epigenetic basis of the differentiation block that characterizes acute myeloid leukemia (AML). AML is the most lethal hematological malignancy and is the cause of more than 10,000 annual US death. AML is typically treated by chemotherapy, though patients often relapse and have limited therapeutic options. The promyelocytic subtype of AML can be cured by “differentiation therapy” – induction of differentiation and inhibition of proliferation with retinoic acid – but this approach has been ineffective in other AML subtypes. Recent work has suggested that this block to non-APL AML differentiation is epigenetic in nature. Stable – yet reversible – chromatin alterations are thought to disable myeloid differentiation gene expression programs in these cells. I have recently established a robust genetic screening approach to uncover epigenetic regulators of non-APL AML differentiation programs. These screens have identified the Chaf1b subunit of the Caf-1 histone remodeling complex as a critical regulator of the Hoxa9- driven AML differentiation block. The overall goal of the work proposed in this application is to determine the molecular, chromatin-based mechanisms by which Chaf1b functions to regulate AML cell differentiation. The goal of my first Aim in this proposal is to use biochemical approaches to identify the proteins and long non- coding RNAs (lncRNAs) that associate with Chaf1b and the greater Caf-1 complex in AML cells. I will then focus on determining which of these interacting proteins and RNAs are most critical in recruiting Chaf1b to its target genomic loci and help sustain its activity as a differentiation-blocking protein. In Aim 2 I will use extensive epigenomic profiling approaches to identify the chromatin remodeling and transcriptomic processes that are altered as cells differentiate in response to inhibition of Chaf1b. I will then compare these epigenomic data to those obtained from my recent profiling of the normal, physiological myeloid differentiation program to determine whether loss of Chaf1b induces differentiation through typical or atypical mechanisms. Finally, in Aim 3 I will determine the potential of Chaf1b as a candidate therapeutic target by testing whether its inhibition induces differentiation and reduces disease burden or affects normal hematopoiesis in mouse AML models. While I am currently a postdoc, the proposed research is to be carried out as an independent investigator, which is my immediate career goal. The initial phase of preparing for this transition has been very promising. I have recently had interviews for tenure-track faculty positions at the University of Pennsylvania, Princeton University, and the Mount Sinai School of Medicine. Mt. Sinai has recently invited me for a second visit and I am awaiting responses from UPenn and Princeton. To help facilitate this transition, I will have collaborative and consultative support of field leaders in hematopoiesis (Dr. David Scadden), AML (Dr. Kimberly Stegmaier), and lncRNA/computational biology (Dr. John Rinn). These scientists are committed to guiding me through the transition process and helping me start my independent career in the strongest possible position. Once independent, my research will focus on epigenetic regulation of AML cell differentiation. However, my long term vision is to bring the concept of targeting cell fate decisions from blood lineage cancers to selected solid tumors of interest. “Differentiation therapy” has been underexplored in solid tumors, but the importance of stemness and de-differentiation programs has been clearly implicated in certain malignancies such as brain cancer. Therefore, toward the end of the proposed funding period, I will aim to establish differentiation-based screening methodology for selected brain cancers and will work on characterizing the molecular mechanisms of screen hits using a combination of genetic, biochemical, epigenomic, and animal models. I believe that this direction will lead to conceptual and therapeutic advances and will have direct clinical relevance.

项目总结/摘要 我在康奈尔大学获得本科学位，在普林斯顿大学获得分子生物学博士学位 目前在中国科学院白血病与淋巴瘤研究所担任博士后研究员， 社会在哈佛医学院和波士顿儿童医院。在研究了 在研究生院乳腺癌转移时，我过渡到了表观遗传学领域的杨学实验室 我是博士后。我在博士后期间接受了广泛的实验和学术培训。我学会了 在我的第一个博士后项目中，基本染色质生物化学的严格要求，最近发表了一份共同第一作者的论文。 基于这项工作的论文。这项研究被作为封面文章刊登在《细胞》杂志上，并报道了 鉴定一种新后生动物表观遗传DNA修饰，N6-甲基腺嘌呤（6 mA）。我的学术 培训涉及广泛的科学写作，使我能够写三个成功的博士后 奖学金申请（来自NIH，ACS和LLS），基于我的工作，施博士两次成功赠款 (from塞缪尔·韦克斯曼癌症研究基金会和哈佛表观遗传学倡议），以及一个 最近在《自然评论分子生物学》杂志上以合著者的身份发表了一篇评论论文。 我目前的博士后研究将我在癌症生物学方面的背景与我最近的培训相结合 染色质生物化学，并侧重于分化块的表观遗传基础， 骨髓性白血病（AML）。AML是最致命的血液恶性肿瘤，是导致超过1000人死亡的原因。 美国每年有1万人死亡。AML通常通过化疗进行治疗，尽管患者经常复发， 有限的治疗选择。早幼粒细胞型AML可通过“分化治疗”治愈- 用视黄酸诱导分化和抑制增殖-但是这种方法已经被 对其他AML亚型无效。最近的研究表明，这种对非APL AML分化的阻断 是表观遗传的稳定但可逆的染色质改变被认为是使骨髓细胞丧失功能的原因。 这些细胞中的分化基因表达程序。我最近建立了一个强大的基因筛选 揭示非APL AML分化程序的表观遗传调节因子的方法。这些屏幕具有 鉴定了Caf-1组蛋白重塑复合物的Chaf 1b亚基作为Hoxa 9- 驱动的AML分化阻滞。本申请中提出的工作的总体目标是确定 Chaf 1b调控AML细胞分化的分子染色质机制。 我的第一个目标是利用生物化学的方法来识别蛋白质和长期的非蛋白质。 AML细胞中与Chaf 1b和更大的Caf-1复合物相关的编码RNA（lncRNA）。然后我将 重点是确定这些相互作用的蛋白质和RNA是最关键的招募Chaf 1b， 靶向基因组位点并帮助维持其作为分化阻断蛋白的活性。在目标2中，我将使用 广泛的表观基因组分析方法，以确定染色质重塑和转录过程 当细胞对Chaf 1b的抑制作出反应而分化时，这些蛋白质会发生改变。然后我会将这些表观基因组 这些数据来自我最近对正常的生理性骨髓分化程序的分析， 确定Chaf 1b的缺失是否通过典型或非典型机制诱导分化。最后在 目的3通过检测Chaf 1b的抑制作用，确定Chaf 1b作为候选治疗靶点的潜力。 在小鼠AML模型中诱导分化并减少疾病负担或影响正常造血。 虽然我目前是一名博士后，但拟议中的研究将作为一名独立调查员进行， 这是我的职业目标筹备这一过渡的最初阶段非常有希望。我 我最近参加了普林斯顿宾夕法尼亚大学终身教职的面试 大学和西奈山医学院。山西奈半岛最近邀请我第二次访问，我 我正在等待宾夕法尼亚大学和普林斯顿大学的答复。为了帮助促进这一过渡，我将与 造血领域领导人（大卫斯卡登博士）、AML领域领导人（金伯利·斯泰格迈尔博士）的咨询支持，以及 lncRNA/计算生物学（John Rinn博士）。这些科学家致力于引导我通过 帮助我在最有利的位置开始我的独立职业生涯。 一旦独立，我的研究将集中在AML细胞分化的表观遗传调控。不过我 长期愿景是将从血液谱系癌症中靶向细胞命运决定的概念引入到选择性癌症中， 感兴趣的实体瘤。“分化治疗”在实体瘤中的探索不足，但分化治疗的重要性是显而易见的。 干细胞和去分化程序已经清楚地涉及某些恶性肿瘤， 癌因此，在拟议的融资期结束时，我将致力于建立基于差异化的 筛选选定的脑癌的方法，并将致力于表征分子机制 筛选命中使用遗传，生物化学，表观基因组和动物模型的组合。我相信这 方向将导致概念和治疗的进步，并将有直接的临床意义。