The Role of BCL2 Mediated Calcium Signaling in Leukemia Stem Cell Metabolism

BCL2 介导的钙信号传导在白血病干细胞代谢中的作用

• 批准号: 10425260
• 负责人: Anagha Inguva
• 金额: $ 5.18万
• 依托单位: UNIVERSITY OF COLORADO DENVER
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-07-01 至 2023-10-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10425260
• 关键词: Acute Myelocytic Leukemia; Address; Affect; Animals; BCL2 gene; Biological Assay; Biological Models; Biology; Calcium; Calcium Binding; Calcium Channel; Calcium Channel Binding; Calcium Channel Inhibition; Calcium Signaling; Cell Death; Cell Survival; Cell physiology; Cellular Metabolic Process; Citric Acid Cycle; Data; Dependence; Disease; Disease Progression; Disease remission; Engraftment; Enzymes; Genetic; Genus Hippocampus; Hematologic Neoplasms; Homeostasis; Human; ITPR1 gene; Immune; Immunocompromised Host; Isocitrate Dehydrogenase; Jordan; Ketoglutarate Dehydrogenase Complex; Link; Maps; Mass Spectrum Analysis; Mediating; Membrane; Metabolic; Metabolism; Mitochondria; Molecular; Molecular Genetics; Movement; Mus; Outcome; Oxidative Phosphorylation; Pathway interactions; Patients; Pharmaceutical Preparations; Pharmacology; Pharmacotherapy; Population; Production; Proteins; Reaction; Regulation; Relapse; Resistance; Role; Sampling; Signal Transduction; Small Interfering RNA; Specimen; Stem Cell Development; Structure-Activity Relationship; Testing; Therapeutic; Therapeutic Agents; Transplantation; Work; base; cancer stem cell; cell killing; cell type; chemotherapy; effective therapy; enzyme activity; experimental study; hematopoietic stem cell differentiation; improved; inhibitor therapy; knock-down; leukemic stem cell; metabolomics; mortality; novel; novel therapeutic intervention; novel therapeutics; overexpression; pyruvate dehydrogenase; release of sequestered calcium ion into cytoplasm; response; self renewing cell; standard of care; stem cell biology; stem cell population; tool; uptake

PROJECT SUMMARY The objective of this study is to define the molecular mechanisms that control survival of malignant stem cells in acute myeloid leukemia (AML). Acute myeloid leukemia (AML) is a hematologic malignancy characterized by poorly differentiated hematopoietic stem cells (25). Traditionally, outcomes have been poor with a 30% response rate to standard of care in patients 65 years and older (25,26). A large cause of resistance and relapse to therapy is the persistence of leukemia stem cells (LSCs) (27-30). LSCs are a population of self-renewing cells that are able to initiate and maintain disease in immune-compromised animals (27). Traditional chemotherapy agents do not efficiently eradicate LSCs, and development of more effective therapies is a significant unmet need (27-30). Previous work from the Jordan lab has shown that LSCs have a unique dependence on oxidative phosphorylation (OXPHOS) for energy production (1-3,24). Further, BCL2 has a non-canonical role in regulating LSC metabolism as inhibition of BCL2 led to decreased OXPHOS and subsequent cell death in primary human LSCs (1-3,24). Analysis of samples from AML patients treated with the BCL2 inhibitor drug venetoclax revealed direct targeting of LSCs, which correlated with a 70% response rate (3). Thus, the underlying premise of the current proposal is that BCL2-mediated control of OXPHOS represents a key vulnerability that can be exploited to selectively target LSCs. Further, determining how OXPHOS is inhibited through BCL2 has implications for improving therapeutic strategies for AML patients. This proposal aims to elucidate the mechanistic link between BCL2 and LSC OXPHOS. In several model systems, BCL2 has been shown to have a non-canonical function in influencing calcium uptake and release at the ER and mitochondria through direct interactions with membrane bound calcium channels (7). Intracellular calcium homeostasis is crucial for cell survival, signaling and metabolism. In particular, the three rate limiting enzymes of the TCA cycle, pyruvate dehydrogenase, alpha-ketoglutarate dehydrogenase and isocitrate dehydrogenase are calcium dependent reactions (7). Therefore, BCL2 mediated calcium movement between the ER and mitochondria could be a mechanistic link between BCL2 and OXPHOS activity. BCL2 modulates the activity of calcium channels at the ER and mitochondria differently, based on the cell type being studied (7). Therefore, my proposal is focused on determining how BCL2 modulates OXPHOS activity by regulating calcium channel biology in leukemia stem cells. My hypothesis is that BCL2 mediated calcium localization is a critical regulator of OXPHOS activity in leukemia stem cells. This proposal will determine whether 1) BCL2 mediates calcium channel biology in LSCs 2) calcium channel biology modulates LSC metabolism/function and 3) regulation of calcium localization is the mechanism of action of BCL2 inhibition in LSCs.

项目摘要 这项研究的目的是定义控制恶性茎存活的分子机制 急性髓样白血病（AML）中的细胞。急性髓细胞性白血病（AML）是一种血液系统恶性肿瘤的特征 通过分化较差的造血干细胞（25）。传统上，结果一直很差，30％ 65岁及以上患者的护理标准的应答率（25,26）。抗药性和复发的重要原因 治疗是白血病干细胞（LSC）的持久性（27-30）。 LSC是自我更新细胞的人群 能够在免疫功能低下的动物中引发和维持疾病（27）。传统的化学疗法 代理不会有效地消除LSC，而开发更有效的疗法是一个重要的未得到的 需要（27-30）。 约旦实验室的先前工作表明，LSC对氧化具有独特的依赖性 能量产生的磷酸化（OXPHOS）（1-3,24）。此外，BCL2在调节中具有非典型作用 LSC代谢作为对BCL2的抑制作用导致OXPHOS降低和随后的细胞死亡。 LSC（1-3,24）。分析用BCL2抑制剂药物Venetoclax治疗的AML患者的样品显示 直接靶向LSC，与70％的响应率相关（3）。因此， 当前的建议是Bcl2介导的OXPHOS的控制代表了可以利用的关键漏洞 有选择地靶向LSC。此外，确定如何通过BCL2抑制Oxphos对 改善AML患者的治疗策略。 该建议旨在阐明BCL2和LSC OXPHOS之间的机械联系。在几种模型中 系统，BCL2已显示在影响钙吸收和释放时具有非典型功能 ER和线粒体通过与膜结合钙通道的直接相互作用（7）。细胞内 钙稳态对于细胞存活，信号传导和代谢至关重要。特别是限制三个速率 TCA循环，丙酮酸脱氢酶，α-酮戊二酸脱氢酶和异位酸的酶的酶 脱氢酶是钙依赖性反应（7）。因此，Bcl2介导的钙运动 ER和线粒体可能是BCL2和OXPHOS活性之间的机械联系。 Bcl2调节 根据所研究的细胞类型，钙通道在ER和线粒体上的活性不同（7）。 因此，我的建议重点是确定Bcl2如何通过调节钙调节OXPHOS活性 在白血病干细胞中的生物学。我的假设是Bcl2介导的钙定位是 白血病干细胞中OXPHOS活性的关键调节剂。该建议将确定1）BCL2是否 LSC中介导钙通道生物学2）钙通道生物学调节LSC代谢/功能和 3）钙定位的调节是LSC中BCL2抑制作用的作用机理。