Dissecting and Targeting Deregulated Mitochondrial Apoptosis in Human Cancer

剖析和靶向人类癌症中失调的线粒体凋亡

• 批准号: 10474551
• 负责人: Loren David Walensky
• 金额: $ 103.12万
• 依托单位: DANA-FARBER CANCER INST
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-08-24 至 2028-07-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10474551
• 关键词: Advanced Development; Apoptosis; Apoptotic; BAX gene; BCL-2 Protein; BCL2 gene; Binding; Binding Sites; Biochemistry; Cancer Biology; Cells; Cellular biology; Cessation of life; Chemicals; Chemistry; Chemoresistance; Cysteine; Development; Enzymes; Family; Goals; Human; Length; Ligands; Long-Chain-Acyl-CoA Dehydrogenase; MCL1 gene; Maintenance; Malignant Neoplasms; Mediating; Metabolic; Mitochondria; Modification; Molecular; Molecular Conformation; Pathogenesis; Pathologic; Pathway interactions; Pediatric Oncologist; Pharmacology; Phase; Post-Translational Protein Processing; Protein Family; Proteins; Proteomics; Regulation; Relapse; Research; Resistance; Role; Signal Pathway; Structure; Surface; Technology; Work; apoptosis deregulation; cancer therapy; fatty acid metabolism; fatty acid oxidation; in vivo evaluation; inhibitor; insight; interdisciplinary approach; monomer; mutant; next generation; novel; novel therapeutics; programs; prototype; refractory cancer; structural biology; tool; tumor metabolism

PROJECT SUMMARY/ABSTRACT BCL-2 proteins participate in a dynamic interaction network that determines whether a cell will live or die. Deregulation of this essential signaling pathway underlies the pathogenesis of human cancer and resistance to treatment. The goal of this R35 research program is to elucidate the fundamental protein interaction mechanisms that drive the apoptotic program and harness these insights to develop next-generation cancer treatments. Over the last five years of R35 support, we applied novel chemical tools and a host of analytical technologies to achieve mechanistic discoveries that revealed new druggable binding sites and compounds to target them. We found that covalent modification of distinct cysteines in pro-apoptotic BAX and anti-apoptotic MCL-1 and BFL-1 differentially regulate their apoptotic functions. Our pursuit of covalent ligands that mimic these post-translational modifications are yielding prototype BAX activators and MCL-1 and BFL-1 inhibitors for cancer therapy. Deciphering how BAX and BAK are directly activated, and the conformational mechanisms that underlie their conversion from latent monomers into toxic mitochondrial oligomers, has also been a major focus of our work. Indeed, the elusive structures of the BAX and BAK death channels represent the “holy grail” of apoptosis research. We recently generated the first full-length homogeneous BAX oligomer (BAXO) amenable to structure- function characterizations, providing a glimpse into the macromolecular organization of a functional BAXO species. BAXO and its mutants are enabling us to pinpoint the structural determinants for each step of the BAX- activation pathway and thus inform new control points for pharmacologic activation of apoptosis. In addition to dissecting these high-priority, canonical BCL-2 protein interactions, we have developed proteomic tools to identify non-canonical targets and recently found that MCL-1 directly interacts with the fatty acid oxidation enzyme VLCAD, revealing a dual role for MCL-1 at the intersection of apoptosis and metabolic regulation. We hypothesize that MCL-1-driven cancers rely on both apoptotic suppression and fatty acid metabolism to maximize pathologic survival, potentially explaining why MCL-1 is the most widely expressed anti-apoptotic protein across human cancers. Here, we build on our newest mechanistic insights to interrogate a spectrum of BCL-2 family interactions that drive human cancer and mine each opportunity to pharmacologically subvert them. Specifically, our next set of R35 goals are: (1) identify the structural and functional determinants that mediate the “execution phase” of mitochondrial apoptosis; (2) solve the structure of a BAX oligomer; (3) characterize the non-canonical role of MCL-1 at the intersection of apoptosis and cancer metabolism; and (4) advance the development and in vivo testing of BCL-2 family molecular modulators as next-generation therapies for human cancer. We tackle these goals using multidisciplinary approaches that span chemistry, structural biology, proteomics, biochemistry, cell biology, and in vivo testing. As a chemical biologist and pediatric oncologist, I am committed to transforming our fresh mechanistic insights into new therapies for relapsed and refractory cancers.

项目摘要/摘要 Bcl-2蛋白参与一个动态交互网络，该网络确定单元格是生命还是死亡。 这种基本信号通路的管制是人类癌症的发病机理和对 治疗。该R35研究计划的目的是阐明基本蛋白质相互作用机制 这推动了凋亡计划并利用这些见解来开发下一代癌症治疗。超过 R35支持的最后五年，我们应用了新型的化学工具和许多分析技术 实现机械性发现，揭示了新的可吸毒结合位点和化合物以靶向它们。我们 发现在促凋亡的Bax和抗凋亡MCL-1和BFL-1中，不同的半胱氨酸的共价修饰 差异调节其凋亡功能。我们追求可以模仿这些翻译后的共价配体 修饰是产生原型BAX激活剂，MCL-1和BFL-1抑制剂进行癌症治疗。 破译Bax和Bak是如何直接激活的，以及构成其基础的概念机制 从潜在的单体转化为有毒的线粒体寡聚物，也是我们工作的重点。 确实，Bax和Bak死亡通道的难以捉摸的结构代表了凋亡的“圣杯” 研究。我们最近生成了第一个全长均质Bax低聚物（Baxo） 功能字符，可瞥见功能性Baxo的大分子组织 Baxo及其突变体使我们能够指出Bax-的每个步骤的结构决定者 激活途径，从而为凋亡的药物学激活提供新的控制点。此外 剖析了这些高优先级，规范的Bcl-2蛋白相互作用，我们开发了蛋白质组学工具 识别非规范目标，最近发现MCL-1与脂肪酸氧化直接相互作用 酶VLCAD，揭示了MCL-1在凋亡和代谢调节的交集中的双重作用。我们 假设MCL-1驱动的癌症依赖于凋亡抑制和脂肪酸代谢 最大化病理生存，有可能解释为什么MCL-1是最广泛表达的抗凋亡 人类癌的蛋白质。在这里，我们以最新的机械见解为基础，询问一系列 BCL-2家庭互动会推动人类癌症并挖掘出每一个机会颠覆它们的机会。 具体而言，我们的下一组R35目标是：（1）确定介导的结构和功能确定词 线粒体凋亡的“执行阶段”； （2）解决Bax低聚物的结构； （3）表征 MCL-1在凋亡和癌症代谢的交集中的非经典作用； （4）推进 Bcl-2家族分子调节剂的开发和体内测试作为人类的下一代疗法 癌症。我们使用跨越化学，结构生物学的多学科方法来解决这些目标 蛋白质组学，生物化学，细胞生物学和体内测试。作为化学生物学家和小儿肿瘤学家，我是 致力于将我们的新机械洞察力转变为接力和难治性癌症的新疗法。