Crosstalk of LKB1 and KEAP1 mutations in driving growth of lung adenocarcinoma

LKB1 和 KEAP1 突变的串扰驱动肺腺癌的生长

基本信息

批准号：
9897626
负责人：
Shyam Biswal
金额：
$ 40.34万
依托单位：
JOHNS HOPKINS UNIVERSITY
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：
2016-04-15 至 2022-03-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9897626
关键词：
5&apos -AMP-activated protein kinase Adenocarcinoma Adenocarcinoma Cell Affect Animals Antioxidants Automobile Driving Cell Line Cell Proliferation Cell Survival Cells Collaborations Data Defect Drug Metabolic Detoxication Gene Mutation Gene Silencing Genetic Genetically Engineered Mouse Growth Histologic Homeostasis Human Impairment In Vitro Knock-out Knowledge Lead Lung Lung Adenocarcinoma Lung Neoplasms Malignant Neoplasms Malignant neoplasm of lung Metabolic Metabolic Pathway Metabolic stress Modeling Molecular Mus Mutate Mutation NADP Non-Small-Cell Lung Carcinoma Nutrient Oncogenic Oxidation-Reduction Pathway interactions Proteins Reaction Reactive Oxygen Species Resistance Role STK11 gene Signal Transduction Stress The Cancer Genome Atlas Transgenic Mice Up-Regulation cell growth energy balance expectation improved in vivo inhibitor/antagonist loss of function mutation lung tumorigenesis metabolomics mortality mouse model mutant neoplastic cell new therapeutic target novel pre-clinical public health relevance response small molecule stable isotope transcriptomics tumor tumor growth

项目摘要

DESCRIPTION (provided by applicant): Nearly 25% of lung adenocarcinomas (LuAD) have deletions or inactivating mutations of the gene for LKB1. In response to metabolic stress, wildtype LKB1 promotes catabolic reactions for generating ATP and conserving antioxidant (NADPH and GSH) levels. Since LKB1 counteracts ROS resulting from metabolic stress, the inactivation of this gene in cancer seems to be contrary to expectations, and indeed, LKB1-deficient cells are relatively resistant to oncogenic transformation and sensitive to metabolic stress. TCGA sequencing data revealed that ~ 50% of LKB1-mutant LuAD also harbor a Kelch-ECH associated protein 1 (KEAP1) mutation. Can the impaired ability of LKB1-deficient cells to adapt to nutrient and metabolic stress be overcome by parallel loss of KEAP1? Our preliminary studies revealed that combined loss of Lkb1 and Keap1 decrease ROS and dramatically enhances tumor growth (histologically, adenocarcinomas), and mortality in KrasG12D driven mouse model of lung cancer. Even in the absence of oncogenic Kras signaling, Keap1-/-Lkb1-/- animals form tumors in the lungs with long latency. Importantly, LKB1-deficient cells showed impaired ability to adapt to metabolic stress in the absence of Nrf2 pathway activation, but this defect was rescued by simultaneous loss of Keap1 signaling. KEAP1 mutations lead to gain of NRF2 function in NSCLC that drives antioxidant pathways and metabolic alterations. We hypothesize that KEAP1 mutations in LKB1 mutated lung adenocarcinoma cells causes gain of NRF2 for ROS detoxification and metabolic pathway alterations, which are critical for tumor cell survival. To exploit the vulnerability of this adaptation, we hypothesize that inhibiting NRF2 in tumors with loss of LKB1 and KEAP1 will decrease tumor growth due to metabolic stress. Specific aim 1 will determine if selective loss of Keap1 signaling in Lkb1 deficient lung cells maintains cellular redox homeostasis and promotes lung tumorigenesis. We have developed mouse models with selective deletion of Lkb1 and Keap1 (with or without oncogenic stress - KrasG12D), transgenic mice expressing Nrf2 with activating mutation combined with Lkb1 deletion as well as LKB1 mutant human lung adenocarcinoma cell lines with gain of Nrf2 or loss of Keap1 function. Specific aim 2 will determine the mechanisms by which loss of Keap1 signaling cooperates with Lkb1 signaling for metabolic alterations to provide survival advantage. Transcriptomic and stable isotope resolved metabolomics studies will be performed. Specific aim 3 will determine if disruption of Nrf2 signaling in our mouse models of SA 1 will decrease tumor growth and improve survival using genetic as well as small molecule approach. In addition to genetic knockout of Nrf2, our preliminary studies have shown the efficacy of a novel small molecule (developed in collaboration with NCATS) for inhibiting NRF2 in vitro and in which will be explored for its potential for targeting the Nrf2 pathway in treating LKB1-mutant cancers. These studies will (a) provide the molecular understanding of why 50% of LKB1 loss coexist with KEAP1 mutations in LuAD (b) create the preclinical knowledge essential for targeting this cooperation.

描述（由申请人提供）：近 25% 的肺腺癌 (LuAD) 具有 LKB1 基因缺失或失活突变。为了应对代谢应激，野生型 LKB1 促进分解代谢反应，以产生 ATP 并保持抗氧化剂（NADPH 和 GSH）水平。由于 LKB1 可以抵消代谢应激产生的 ROS，因此该基因在癌症中的失活似乎与预期相反，事实上， LKB1 缺陷细胞对致癌转化具有相对抵抗力，并且对代谢应激敏感，约 50% 的 LKB1 突变型 LuAD 也含有 Kelch-ECH 相关蛋白 1 (KEAP1) 突变，可导致 LKB1 的能力受损。 KEAP1 的同时缺失可以克服细胞适应营养和代谢应激的缺陷吗？我们的初步研究表明，Lkb1 和 Keap1 的联合缺失会降低 ROS 并显着促进肿瘤生长。（组织学上，腺癌）和 KrasG12D 驱动的肺癌小鼠模型中的死亡率即使在没有致癌的 Kras 信号传导的情况下，Keap1-/-Lkb1-/- 动物也会在肺部形成具有较长潜伏期的肿瘤。在没有 Nrf2 通路激活的情况下，适应代谢应激的能力受损，但通过同时丢失 KEAP1 信号传导，可以弥补这一缺陷，从而获得增益。我们研究了 LKB1 突变肺腺癌细胞中 NRF2 功能的驱动抗氧化途径和代谢改变，导致 NRF2 获得 ROS 解毒和代谢途径改变，这对于肿瘤细胞的生存至关重要。适应，我们追求在 LKB1 和 KEAP1 缺失的肿瘤中抑制 NRF2 将减少代谢应激引起的肿瘤生长，具体目标 1 将确定 Keap1 信号传导是否选择性缺失。在 Lkb1 缺陷的肺细胞中维持细胞氧化还原稳态并促进肺肿瘤发生我们开发了选择性删除 Lkb1 和 Keap1 的小鼠模型（有或没有致癌应激 - KrasG12D）、表达具有激活突变的 Nrf2 以及 Lkb1 删除的转基因小鼠。获得 Nrf2 或丧失 Keap1 功能的 LKB1 突变人肺腺癌细胞系将确定具体目标 2。将进行转录组学和稳定同位素解析代谢组学研究，确定 Keap1 信号传导缺失与 Lkb1 信号传导协同代谢改变的机制，以确定 SA 1 小鼠模型中 Nrf2 信号传导的破坏是否会减少肿瘤。除了 Nrf2 的基因敲除之外，我们的初步研究还表明了一种新型小分子（与 NCATS 合作开发）的功效。用于在体外抑制 NRF2，并将探索其靶向 Nrf2 通路治疗 LKB1 突变癌症的潜力。这些研究将 (a) 从分子角度理解为什么 50% 的 LKB1 缺失与 LuAD 中的 KEAP1 突变共存。 b) 创建针对这种合作所必需的临床前知识。