Investigating the role of epitranscriptomic A-to-I RNA editing in T-cell acute lymphoblastic leukemia

项目摘要 这项建议的最终目标是解决一个迫切的未得到满足的医疗需求，以确定新的 癌基因转化的表位转录机制将指导诊断和治疗的发展 预测和预防T细胞急性淋巴母细胞瘤进展的治疗策略 白血病(T-ALL)。急性淋巴细胞性白血病(ALL)是我国最常见的血液病 年龄在14岁以下的儿童。尽管在强化化疗方面取得了进展，但20%-25%的儿童 超过50%的成年患者对治疗和复发表现出抵抗。广泛的反常 表位转录的ADAR1介导的腺苷到肌苷(A-to-I)RNA编辑与 几种癌症类型的临床特点及白血病起始细胞的产生 增强了支持生存和自我更新的能力。有趣的是，Janus Kinase(JAK)/STAT的激活 白介素7(IL-7)信号转导关键干细胞调控通路ADAR1-LIN28和 包括T-ALL在内的血液系统恶性肿瘤中的促生存因子。我们的中心假设是 突变的促炎信号，如Noch和JAK/STAT信号通路，诱导异常 增强存活率的T-ALL启动细胞中ADAR1激活驱动的RNA编辑 和自我更新能力。这三个具体目标将是(1)检查ADAR1介导的RNA编辑 通过增强T-ALL LIC促进正常T细胞前体细胞向T-ALL LIC的致癌转化 生存和自我更新途径；(2)检测T-ALL LIC细胞ADAR1活性是否增强 由于Notch或JAK/STAT信号通路被激活，最后(3)确定是否直接 ShRNA策略抑制ADAR1活性损害T-ALL细胞存活和自我更新 维修。这项提议将利用已建立的初级T-ALL患者样本的生物库， 以及年龄匹配的健康对照样本。此外，基于慢病毒的工具和建立的健壮 在体人异种移植T-ALL小鼠模型将用于选择性消融ADAR1转录本 深入探讨ADAR1表达与耐药T细胞产生的关系 全启动LIC电池。详细的功能和机制慢病毒导向的转录本过表达 基因敲除研究将验证敏感的整个转录组RNA测序 ADAR1表达与LIC存活和自我更新信号通路及干细胞基因表达 签名。这一研究策略独一无二地融入了我的职业发展计划，包括 在数据管理、基础研究和翻译研究、研究伦理以及 专业和领导力发展。通过更机械化地理解 ADAR1在癌症中的应用，这笔赠款将为未来的RNA编辑酶检测和抑制策略提供信息，这些策略可能 有助于消除癌症耐药性和复发。

Project Summary The ultimate goal of this proposal is to address a compelling unmet medical need to identify novel epitranscriptomic mechanisms of oncogenic transformation that will guide development of diagnostic and therapeutic strategies capable of predicting and preventing progression of T-cell acute lymphoblastic leukemia (T-ALL). Acute lymphoblastic leukemia (ALL) is the most prevalent hematological cancer in children younger than 14 years of age. Despite progress in intensive chemotherapy, 20-25% of pediatric and over 50% of adult patients show resistance to therapy and relapse. Widespread aberrant epitranscriptomic ADAR1-mediated adenosine-to-inosine (A-to-I) RNA editing has been associated with clinical characteristics of several cancer types and generation of leukemia initiating cells (LICs) with enhanced pro-survival and self-renewal capacity. Interestingly, activation of janus kinase (JAK)/STAT signaling by interleukin-7 (IL-7) drives expression of key stem cell regulatory pathway ADAR1-LIN28 and pro-survival factors in hematological malignancies including T-ALL. Our central hypothesis is that mutational pro-inflammatory signals, such as NOTCH and JAK/STAT signaling pathway, induce aberrant RNA editing driven by ADAR1 activation in T-ALL-initiating cells that accentuated by enhanced survival and self-renewal capacity. The three specific aims will be (1) examine if the ADAR1-mediated RNA editing promotes oncogenic transformation of normal T cell progenitor to T-ALL LICs by enhancing T-ALL LIC survival and self-renewal pathways; (2); examine whether ADAR1 activity is enhanced in T-ALL LIC cells due to NOTCH or JAK/STAT signaling pathway activation, and lastly (3) determine whether direct inhibition of ADAR1 activity by shRNA strategy impairs the survival and self-renewal impairs T-ALL LIC maintenance. This proposal will utilize established biorepository of primary T-ALL patient specimen, along with age-matched healthy control samples. In addition, lentiviral-based tools and established robust in vivo human xenograft T-ALL mouse models will be used for selective ablation of ADAR1 transcripts to thoroughly investigate the relationship between ADAR1 expression and generation of drug-resistant T- ALL-initiating LIC cells. Detailed functional and mechanistic lentiviral-directed transcript overexpression and knockdown studies will validate sensitive whole transcriptome RNA-Sequencing that correlate ADAR1 expression with LIC survival and self-renewal signaling pathway and stem cell gene expression signatures. This research strategy is uniquely integrated into my career development plan, including additional trainings in data management, basic and translational research, research ethics, and professional and leadership development. By providing a more mechanistic understanding of the role of ADAR1 in cancer, this grant will inform future RNA editase detection and inhibition strategies that may help to obviate cancer resistance and relapse.