Targeting mitochondrial dynamics in drug-resistant acute myeloid leukemia

项目摘要/摘要 急性髓系白血病(AML)是成人第二常见的白血病，通常有一种 预后和高死亡率，这体现在28%的五年总存活率。Ventoclax，一种选择性的 抗凋亡蛋白BCL-2的抑制剂，已获得FDA批准用于治疗AML。尽管 AML患者对万乃馨有希望的早期反应，延长治疗和治疗后出现耐药性 强调了深入了解根本机制的紧迫性。最近，我发现 急性髓系白血病细胞的线粒体在耐药时会发生形态变化。使用全基因组 CRISPRi在人类AML筛查中，我发现参与线粒体结构的基因是合成致死基因 AML中ventoclax的漏洞。耐万乃馨的AML细胞线粒体主动修改其 防止细胞凋亡的结构和功能。支持这一点的是线粒体的主要调节者OPA1 冠状突起结构和线粒体伴侣蛋白ClpB在耐万乃馨的AML中显著上调 细胞相对于敏感细胞。ClpB直接与OPA1相互作用以维持生理线粒体 形态学。有希望的是，基因上的ClpB或OPA1消融增强了维尼托-克拉克斯诱导的AML细胞的凋亡， 通过促进眉骨重塑和线粒体应激。 这项建议旨在通过1)描述机制细节来利用这些观察结果， 使用超分辨技术，线粒体动态和稳态导致急性髓系白血病耐药的获得 显微镜，电子断层扫描和生化技术，以及2)评估治疗潜力 干扰线粒体结构以增强临床前急性髓系白血病小鼠模型的静脉锁骨作用。这项研究 将具有重大的临床影响，因为它可以作为开发新的联合治疗的基础 针对急性髓系白血病患者的靶向治疗。 此外，这份提案概述了我的职业发展计划，以获得过渡所需的培训 成为一名成功的独立调查员。这包括我尊敬的导师伊安尼斯博士的指导 Aifantis，血液恶性肿瘤和老鼠模型专家；2)由专家顾问团进行科学培训， 由拉乌尔·蒂贝斯博士、汉斯-威廉·斯诺克博士、基万茨·伯索博士和埃夫里皮迪斯·加瓦蒂奥蒂斯博士组成，他们都在顶级研究机构 纽约大学；3)使用最先进的设备进行实践培训，包括与Eli博士合作的超分辨率显微镜 Rothenberg；4)与显微镜和生物信息学专家合作；5)职业发展课程 由纽约大学赞助。艾芬蒂斯博士的实验室和纽约大学病理学系将提供资源 对我的训练和研究至关重要，确保了我的成功。这一广泛的职业成长计划将指导 我在指导阶段出类拔萃地成为一名独立的学术科学家。总的来说，建议的 研究和职业发展计划预计将产生对规避 AML的靶向治疗耐药性，并为我作为一名独立研究员的未来研究奠定了基础。

PROJECT SUMMARY/ABSTRACT Acute myeloid leukemia (AML) is the second most common leukemia in adults and typically has a dismal prognosis and high mortality, which is exemplified by a 28% five-year overall survival rate. Venetoclax, a selective inhibitor of the anti-apoptotic protein BCL-2, has received FDA approval for the treatment of AML. Despite promising early responses of AML patients to venetoclax, drug resistance ensues after prolonged treatment and highlights the urgency for a deep understanding of the underlying mechanisms. Recently, I discovered that mitochondria in AML cells undergo a morphological change upon venetoclax resistance. Using a genome-wide CRISPRi screen in human AML, I identified genes involved in mitochondrial structure as synthetic lethal vulnerabilities for venetoclax in AML. Mitochondria of venetoclax-resistant AML cells actively modify their architecture and function to prevent apoptosis. Supporting this, OPA1, the master regulator of mitochondrial cristae structure, and CLPB, a mitochondrial chaperonin, were strikingly upregulated in venetoclax-resistant AML cells relative to the sensitive cells. CLPB directly interacts with OPA1 to maintain the physiological mitochondrial morphology. Promisingly, genetic CLPB or OPA1 ablation enhances venetoclax-induced apoptosis of AML cells, by promoting cristae remodeling and mitochondrial stress. This proposal aims to leverage these observations by 1) delineating the mechanistic details by which mitochondrial dynamics and homeostasis lead to acquisition of drug resistance in AML, using super-resolution microscopy, electron tomography, and biochemical techniques, and 2) assessing the therapeutic potential of perturbing mitochondrial structure to augment venetoclax action in preclinical AML mouse models. This research stands to have significant clinical impact, because it can serve as a basis for developing new combinational targeted therapies for patients with AML. In addition, this proposal outlines my career development plan for obtaining the requisite training to transition into a successful independent investigator. This includes 1) guidance from my esteemed mentor Dr. Iannis Aifantis, expert in blood malignancies and mouse models; 2) scientific training by an expert advisory panel, consisting of Drs. Raoul Tibes, Hans-Willem Snoeck, Kivanc Birsoy and Evripidis Gavathiotis, all in top institutes of NYC; 3) hands-on training using state-of-art equipment, including super-resolution microscopy with Dr. Eli Rothenberg; 4) collaboration with experts in microscopy and bioinformatics; and 5) career development courses sponsored by NYU. The laboratory of Dr. Aifantis and NYU Department of Pathology will provide the resources critical to my training and research, ensuring my success. This extensive professional growth program will guide me during the mentored phase excelling as an independent academic scientist. Collectively, the proposed research and career development plans are expected to generate data with significant impact on circumventing targeted-therapy resistance in AML and setting the basis of my future research as an independent researcher.