(PQ5) Imaging mitochondrial heterogeneity in LKB1 mutant lung cancer

(PQ5) LKB1 突变肺癌线粒体异质性成像

基本信息

批准号：
9750637
负责人：
David B Shackelford
金额：
$ 34.17万
依托单位：
UNIVERSITY OF CALIFORNIA LOS ANGELES
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：
2016-09-01 至 2021-08-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9750637
关键词：
Adenosine Monophosphate Anabolism Anions Antibodies Apoptosis Apoptotic Area Avidity Biochemical Biology Cancer Patient Cancer cell line Cardiolipins Cell Line Chemicals Complex Coupled Coupling Data Defect Development Diagnosis Dissection Electron Microscopy Exposure to Genetic Genetically Engineered Mouse Genus Hippocampus Goals Health Heterogeneity Homeostasis Human Image In Vitro Inner mitochondrial membrane Lead Link Longitudinal Studies Lung Neoplasms Malignant Neoplasms Malignant neoplasm of lung Maps Measurement Measures Mediating Membrane Potentials Mitochondria Modeling Molecular Morphology Mus Mutate Mutation Neoplasm Metastasis Nodule Non-Small-Cell Lung Carcinoma Outer Mitochondrial Membrane Pathway interactions Patients Phosphotransferases Physiological Population Positron-Emission Tomography Protein Tyrosine Phosphatase Public Health RNA Interference Regulation STK11 gene Signal Pathway Stress Structure Testing Transmission Electron Microscopy Tumor Suppressor Genes Tumor Suppressor Proteins Work Xenograft procedure field study imaging detection improved outcome in vivo inhibitor/antagonist lung development lung tumorigenesis microscopic imaging mitochondrial membrane mutant neoplastic cell new therapeutic target novel novel therapeutics radiotracer restoration sensor tumor tumor progression voltage

项目摘要

ABSTRACT The goal of this study is to utilize PET imaging in GEMMs to perform a mechanistic study of mitochondrial heterogeneity following inactivation of the LKB1/AMPK signaling pathway during lung tumor development. LKB1 functions as a master kinase that regulates cellular energetics and mitochondrial function through activation of the adenosine monophosphate activated kinase (AMPK) that is frequently mutated in cancer. LKB1 mutations lead to inactivation of the AMPK signaling pathway resulting in severe defects in cellular energetics and mitochondrial homeostasis. This results in highly variable mitochondrial pools within human and mouse tumors that consist of numerous atypical mitochondria of differing size, morphology and function that we define as mitochondrial heterogeneity,. However, little is understood at a physiological or mechanistic level how mitochondrial heterogeneity resulting from LKB1 inactivation impact lung tumorigenesis or therapy. We examined mitochondrial structural and functional heterogeneity in lung tumors in vivo by coupling electron microscopy (EM) and positron emission tomography (PET) imaging of Lkb1-/- genetically engineered mouse models (GEMMs). Using a voltage sensitive mitochondrial specific radiotracer [18F]-Fluorobenzyl- triphenylphosphonium (FTP) we are able to measure mitochondrial membrane potential (∆Ψ) in lung tumors by PET imaging. FTP PET imaging identified lung tumor populations with heterogeneous mitochondrial activity in vivo. Additionally, mitochondrial defects sensitize LKB1-/- tumor cells to undergo mitochondrial outer membrane permeabilization (MOMP) and apoptosis and we discovered the LKB1/AMPK pathway is a potential regulator of MOMP and apoptosis through voltage dependent anion 1 (VDAC1). Lastly, as a result of a synthetic lethal chemical screen, we identified protein tyrosine phosphatase mitochondria 1 (PTPMT1), a key regulator of cardiolipin biosynthesis and mitochondrial integrity as a novel therapeutic target in LKB1-/- lung cancer. We hypothesize that inactivation of the LKB1 tumor suppressor induces heterogeneity in mitochondrial structure and function that drives lung tumor development. To test this hypothesis we will integrate PET and EM imaging of Lkb1-/- GEMMs of lung cancer to longitudinally study mitochondrial heterogeneity at distinct stages of lung tumor development. In Aim1 we will use FTP PET imaging to map mitochondrial heterogeneity and dynamics in vivo during lung tumorigenesis following LKB1 loss. In Aim 2 we will identify the molecular mechanisms by which the LKB1/AMPK pathway regulates the mitochondrial outer membrane. In Aim 3 perform an in vivo dissection of the PTPMT1-cardiolipin pathway in LKB1-/- lung tumors. We propose first-in- field studies that will advance our fundamental understanding of mitochondrial biology and the impact of mitochondrial heterogeneity has on promoting lung tumorigenesis. The proposed work has relevance to human health in the areas of PET imaging based detection diagnosis of lung cancer as well as the development of new therapies to improve outcomes for lung cancer patients.

抽象的这项研究的目的是利用PEMM中的PET成像进行线粒体的机械研究肺部肿瘤发育过程中LKB1/AMPK信号通路失活后的异质性。 LKB1充当主激酶，可调节细胞能量和线粒体功能经常在癌症中突变的单磷酸腺苷激活激活激活激活。 LKB1突变导致AMPK信号通路失活，导致细胞中严重缺陷能量和线粒体稳态。这导致人类和小鼠肿瘤由许多不同的线粒体组成，具有分化尺寸，形态和功能我们将其定义为线粒体异质性。但是，在物理或机械水平上几乎没有理解 LKB1失活导致的线粒体异质性如何影响肺肿瘤发生或治疗。我们通过与电子耦合相关的肺肿瘤中检查的线粒体结构和功能异质性显微镜（EM）和正电子发射断层扫描（PET）LKB1 - / - 一般工程小鼠的成像模型（宝石）。使用电压敏感的线粒体特异性放射性训练仪[18F] -Fluorobenzyl- Triphenylphosphonium（FTP）我们能够通过肺肿瘤中的线粒体膜电位（∆ψ）测量宠物成像。 FTP PET成像鉴定出具有异质线粒体活性的肺肿瘤种群体内。另外，线粒体缺陷敏感性LKB1 - / - 肿瘤细胞进行线粒体外部膜通透性（MOMP）和凋亡，我们发现LKB1/AMPK途径是潜在的通过电压依赖性阴离子1（VDAC1）的MOMP和凋亡调节剂。最后，由于合成致死化学筛选，我们鉴定了蛋白质酪氨酸磷酸酶线粒体1（PTPMT1），钥匙 Cardiolipin生物合成和线粒体完整性的调节剂，作为LKB1 - / - 肺中的新型热靶癌症。我们假设LKB1肿瘤抑制剂失活会诱导线粒体异质性驱动肺部肿瘤发育的结构和功能。为了检验这一假设，我们将整合宠物和 LKB1的EM成像 - / - 肺癌的宝石，以纵向研究线粒体异质性。肺部肿瘤发育的阶段。在AIM1中，我们将使用FTP PET成像来映射线粒体异质性 LKB1损失后肺肿瘤发生过程中的体内动力学。在AIM 2中，我们将确定分子 LKB1/AMPK途径调节线粒体外膜的机制。在目标3中在LKB1 - / - 肺肿瘤中对PTPMT1-钙钙蛋白酶途径进行体内解剖。我们提出了第一个将提高我们对线粒体生物学的基本理解的现场研究以及线粒体异质性对促进肺部肿瘤发生。拟议的工作与基于宠物成像的肺癌诊断和开发新疗法以改善肺癌患者的预后。