Roles for Intracellular pH Dynamics in Cancer

细胞内 pH 动态在癌症中的作用

基本信息

批准号：
9906489
负责人：
DIANE L BARBER
金额：
$ 8.41万
依托单位：
UNIVERSITY OF CALIFORNIA, SAN FRANCISCO
依托单位国家：
美国
项目类别：
财政年份：
2016
资助国家：
美国
起止时间：
2016-06-01 至 2021-05-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9906489
关键词：
6-Phosphofructokinase Address Adult Affinity Amino Acid Substitution Amino Acids BRAF gene Behavior Biochemistry Bioinformatics Biosensor Cancer Cluster Carbon Cell Cycle Progression Cell physiology Cells Cellular Morphology Cellular biology Classification Consumption Data Databases Detection Disease Progression Drosophila genus Dysplasia Enzymes Epidermal Growth Factor Receptor Exploratory/Developmental Grant for Diagnostic Cancer Imaging Genetic Glucose Glycolysis Heterogeneity Histidine International Lactate Dehydrogenase Ligand Binding Magnetic Resonance Spectroscopy Malignant Neoplasms Measures Mediating Metabolic Metabolism Methods Mitochondria Mitochondrial Matrix Molecular Molecular Conformation Mutation Neoplasm Metastasis Normal Cell Oncogenes Oncogenic Outcome Oxidative Phosphorylation PHluorin Post-Translational Protein Processing Property Protein Conformation Proteins Proton-Motive Force Publishing Reporting Role Shapes Signal Pathway Somatic Mutation Structure TP53 gene Testing Therapeutic Time Tissues United States National Institutes of Health Warburg Effect Work aerobic glycolysis base cancer cell cancer subtypes cancer type cell behavior cell motility design in vivo insight lysylglutamic acid metabolic profile molecular dynamics mouse model neoplastic cell new therapeutic target novel strategies novel therapeutic intervention pressure prognostic programs protein function protonation public health relevance sensor structural biology tool tumor behavior tumor heterogeneity tumor metabolism tumor progression tumorigenesis tumorigenic

项目摘要

DESCRIPTION (provided by applicant): Constitutively increased intracellular pH (pHi) is common to most cancers regardless of their tissue origin or genetic background. However, how a higher pHi enables disease progression and the molecular mechanisms mediating pHi-dependent cancer cell behaviors are understudied and mostly not understood. We previously revealed how increased pHi can enable metastatic progression by regulating pH-sensing proteins controlling directed cell migration. We now will address how increased pHi enables three additional cancer cell behaviors: tumor formation, metabolic reprograming and retention of recurring somatic mutations. We exploit our unique expertise in resolving at the molecular, cellular and tissue levels how pHi dynamics regulates cell functions. We have a strong track record of bridging structural and cell biology to reveal the design principles and functional significance of pH sensors, defined as proteins with activities or ligand binding affinities regulated within the narrow pH range of the cell. To identify pH sensors we integrate analyses of signaling pathways, cancer mutations databases, and titrating networks of ionizable residues in proteins with molecular dynamics simulations, biochemistry and cell physiology. Our expertise in measuring real-time pHi dynamics in vivo using a genetically encoded biosensor brings a distinct new approach to understanding cancer cell biology. In Aim 1 we will test the hypothesis that increased pHi is necessary and sufficient for tumorigenic behaviors. We will resolve mechanisms for pHi-dependent tumorigenesis in mouse models to determine the synthetic lethality we reported in Drosophila with loss of H+ efflux and oncogene expression. We will determine how increased pHi in the absence of oncogenes induces dysplasia, and measure spatial and temporal pHi dynamics during tumorigenesis as a new metric to inform us about heterogeneity of tumor cells. These studies include a structural and functional analysis of pH sensors predicted to enable oncogenic behaviors. In Aim 2 we will test the hypothesis that increased pHi enables metabolic reprograming in cancer. We will determine mechanisms for how increased pHi can promote a switch in glucose utilization from mitochondrial oxidative phosphorylation to increased aerobic glycolysis. These studies include a structural and functional analysis of the recognized pH-sensitive glycolytic enzymes phosphofructokinase-1 and lactate dehydrogenase. We also resolve how increased pHi suppresses mitochondrial oxidative phosphorylation and regulates carbon fates, determined by magnetic resonance spectroscopy. In Aim 3 we will test the hypothesis that increased pHi provides a selective pressure for the retention of somatic mutations with histidine residues. These studies are supported by findings from an R21 award that verified pH sensitivity of recurring somatic mutations in cancers and with bioinformatics analyses identified cancer subtypes based on amino acid substitution signatures, which we will test for shared functional properties. Outcomes of our proposal will generate new insights on molecular mechanisms enabling cancer that can inform therapeutic approaches targeting pH sensors to limit disease progression.

描述（由申请人提供）：无论其组织起源或遗传背景如何，细胞内 pH (pHi) 的组成性升高对于大多数癌症来说都是常见的。然而，较高的 pHi 如何导致疾病进展以及介导 pHi 依赖性癌细胞行为的分子机制尚未得到充分研究。我们之前揭示了 pHi 增加如何通过调节控制定向细胞迁移的 pH 感应蛋白来促进转移进展，现在我们将讨论 pHi 增加如何促进三种额外的癌细胞行为：肿瘤形成、代谢。我们利用我们在分子、细胞和组织水平上解决 pHi 动力学如何调节细胞功能的独特专业知识，我们在桥接结构和细胞生物学方面拥有丰富的经验，可以揭示设计原理和功能意义。 pH 值，定义为在细胞的狭窄 pH 范围内调节活性或配体结合亲和力的蛋白质。为了识别 pH 传感器，我们利用分子动力学分析了信号通路、癌症突变数据库和蛋白质中可电离残基的滴定网络。我们在使用基因编码生物传感器测量体内实时 pHi 动态方面的专业知识为理解癌细胞生物学提供了一种独特的新方法。在目标 1 中，我们将测试以下假设：增加 pHi 对于癌症细胞生物学来说是必要且充分的。我们将解决小鼠模型中 pHi 依赖性肿瘤发生的机制，以确定我们在果蝇中报告的 H+ 外流和癌基因表达缺失的综合致死率。 In Aim 2 中，在没有癌基因的情况下会诱导发育异常，并测量肿瘤发生过程中的空间和时间 pHi 动态，作为一种新的指标来告知我们肿瘤细胞的异质性。我们将检验 pHi 增加能够促进癌症代谢重编程的假设。我们将确定 pHi 增加如何促进葡萄糖利用从线粒体氧化磷酸化转变为增加有氧作用的机制。这些研究包括对公认的 pH 敏感糖酵解酶磷酸果糖激酶 1 和乳酸脱氢酶的结构和功能分析，我们还通过磁共振波谱法确定了增加的 pHi 如何抑制线粒体氧化磷酸化和调节碳命运。将检验以下假设：pHi 的增加为保留组氨酸残基的体细胞突变提供了选择压力。这些研究得到了一项研究结果的支持。 R21 奖项验证了癌症中反复出现的体细胞突变的 pH 敏感性，并通过生物信息学分析根据氨基酸取代特征识别了癌症亚型，我们将测试其共同的功能特性，我们提案的结果将产生关于使癌症能够发生的分子机制的新见解。为针对 pH 传感器的治疗方法提供信息，以限制疾病进展。