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：
10469119
负责人：
DIANE L BARBER
金额：
$ 9.33万
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 2023-03-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10469119
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（由适用提供）：无论其组织起源或遗传背景如何，大多数癌症的细胞内pH（PHI）都是常见的。但是，如何了解较高的PHI使疾病的进展和介导PHI依赖性癌细胞行为的分子机制被理解，并且大多数情况尚不清楚。我们先前揭示了增加的PHI如何通过调节控制定向细胞迁移的pH传感蛋白来实现转移性进展。现在，我们将解决增加的PHI如何实现三种其他癌细胞行为：形成肿瘤，代谢重编程和反复出现的体细胞突变的保留。我们利用我们在分子，细胞和组织水平解决PHI动力学如何调节细胞功能方面的独特专业知识。我们在桥接结构和细胞生物学方面有很强的记录，以揭示pH传感器的设计原理和功能意义，该pH传感器定义为蛋白质，其活性或配体结合亲和力在细胞的狭窄pH范围内调节。为了识别pH传感器，我们整合了具有分子动力学模拟，生物化学和细胞生理学的蛋白质中可离子残差的信号通路，癌症突变数据库和滴定网络的分析。我们使用一般编码的生物传感器在体内测量实时PHI动力学方面的专业知识为理解癌细胞生物学的新方法带来了独特的新方法。在AIM 1中，我们将检验以下假设：增加的PHI是必需的，足以满足肿瘤性行为。我们将解决小鼠模型中PHI依赖性肿瘤的机制，以确定我们在果蝇中报告的合成致死性，而H+外排和癌基因表达的损失。我们将在没有癌基因的情况下确定PHI如何增加PHI会诱发发育异常，并在肿瘤过程中测量空间和临时PHI动力学，以告知我们有关肿瘤细胞异质性的信息。这些研究包括对pH传感器的结构和功能分析，该pH传感器预测可实现致癌行为。在AIM 2中，我们将检验以下假设，即增加PHI可以在癌症中代谢重编程。我们将确定增加PHI如何促进从线粒体氧化磷酸化到增加有氧糖酵解的葡萄糖利用的转换的机制。这些研究包括对公认的pH敏感糖酶1的结构和功能分析，并磷酸果果糖酶-1和脱氢酶脱氢酶。我们还解决了增加的PHI如何抑制线粒体氧化磷酸化并通过磁共振光谱确定的碳命运。在AIM 3中，我们将检验以下假设：增加PHI为保留组氨酸保留的体细胞突变提供了选择性压力。这些研究得到了R21奖的发现支持，该结果验证了癌症中反复出现的体细胞突变的pH敏感性，并且通过生物信息学分析确定了基于氨基酸替代特征的癌症亚型，我们将测试共享功能性能。我们提案的结果将产生对癌症的分子机制的新见解，该癌症可以告知靶向pH传感器以限制疾病进展的治疗方法。