Dissecting Nrf2-dependent HIF1a activation mechanism in arsenic-induced cancer stem-like cells

剖析砷诱导的癌症干细胞样细胞中 Nrf2 依赖性 HIF1a 激活机制

• 批准号: 10515655
• 负责人: Fei Chen
• 金额: $ 35.55万
• 依托单位: STATE UNIVERSITY NEW YORK STONY BROOK
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-09-15 至 2025-10-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10515655
• 关键词: Address; Affect; Arsenic; Biochemical; Biological Assay; Bladder; CRISPR/Cas technology; Carcinogens; Cells; ChIP-seq; Characteristics; Citric Acid Cycle; Consumption; Country; Data; Deposition; Environmental Carcinogens; Environmental Exposure; Epigenetic Process; Epithelial Cells; Exhibits; Exposure to; Food; Fruit; Generations; Genes; Genetic Transcription; Glucose; Glycolysis; Grain; HIF1A gene; Hematopoietic System; Histone H3; Human; In Vitro; Industrialization; Irrigation; Kidney; Link; Liver; Lung; Lysine; MAPK8 gene; Maintenance; Malignant - descriptor; Malignant Neoplasms; Malignant neoplasm of lung; Metabolic; Metabolism; Metals; Methylation; Minerals; Mitochondria; Organ; Oxidative Phosphorylation; Pathway interactions; Pattern; Persons; Planet Earth; Play; Proteomics; Public Health; Research; Rice; Role; Signal Transduction; Skin; Soil; Testing; Translating; Ubiquitination; United States; Vegetables; Water; Workplace; arsenic carcinogenesis; bronchial epithelium; cancer type; carcinogenicity; chromatin remodeling; epigenetic marker; ground water; histone methylation; in vivo; inhibitor; metabolomics; mitochondrial metabolism; response; self-renewal; stem cells; stem-like cell; stemness; targeted cancer therapy; transcription factor; transcriptome sequencing; transcriptomics

Long-term exposure to arsenic, esp. the inorganic trivalent arsenic (iAs), a human carcinogen that occurs naturally in the earth's crust or work place due to industrial settings, has been linked to various types of cancers, esp. lung cancer. It has been known for decades that multiple different mechanisms might be involved in iAs-induced malignant transformation. However, whether and how iAs induces cancer stem-like cells (CSCs) from non-stem cells hadn’t been studied. We had previously shown that consecutive treatment of the human bronchial epithelial cells with 0.125 to 0.25 M (~9 to 18ppb) iAs for six months induced generation of the CSCs. In addition to the higher expression of the stemness circuit genes, including Oct4, Sox2, myc, Klf4, etc., these iAs-induced CSCs also exhibited a unique metabolic pattern featured with an active glycolysis and diminished mitochondrial oxidative phosphorylation (OXPHOS). ChIP-seq analysis of the parental cells and the iAs-induced CSCs revealed a substantial increase in the enrichment of histone H3 lysine4 trimethylation (H3K4me3), an active epigenetic marker for gene transcription, among genes critical for the stemness and glycolysis of the CSCs. To understand how iAs induces these metabolic and epigenetic changes and the generation of the CSCs, we recently also investigated the capability of iAs on the activation of Nrf2 and HIF1 signaling through both biochemical and ChIP-seq approaches. The data indicate that Nrf2 and HIF1 may serve as initiators for the metabolic and epigenetic reprograming, and the acquisition of the CSC features. Accordingly, we hypothesize that iAs-activated Nrf2 is an upstream activator for HIF1 signaling linked to glycolysis, and the subsequent epigenetic reprogramming and generation of the CSCs. To test this hypothesis, the following three specific aims will be pursued: Aim1, dissecting Nrf2 activation pathways with an emphasis on the iAs-induced ubiquitination and degradation of Keap1, the endogenous inhibitor of Nrf2; Aim 2, investigating mechanisms of Nrf2-dependent initiation of HIF1 signaling in the cells in response to iAs; and Aim 3, understanding how iAs-induced Nrf2-HIF1 signaling shifts the metabolism from mitochondrial TCA cycle to glycolysis that linked to reprogramming of the histone methylation profiles and the generation of CSCs. We expect that the data from the completion of this research plan will be the first to reveal the importance of Nrf2 and HIF1 in iAs- induced CSCs, which may be translated into new strategies of cancer therapy by targeting the Nrf2- HIF1 signaling and the CSCs.

长期接触砷，尤其是。无机三价砷（IAS），一种人类致癌物 由于工业环境而自然发生在地壳或工作地点，与各种 癌症类型，特别是。肺癌。数十年来，已经知道多种不同的机制 可能参与IAS引起的恶性转化。但是，IAS是否以及如何影响 来自非茎细胞的癌症干细胞（CSC）尚未研究。我们以前表明 连续治疗人支气管上皮细胞，用0.125至0.25M（〜9至18ppb）IAS治疗 六个月诱导CSC产生。除了较高的茎表达 电路基因，包括OCT4，SOX2，MYC，KLF4等，这些IAS诱导的CSC也暴露了独特的 具有活性糖酵解和线粒体氧化降低的代谢图案。 磷酸化（OXPHOS）。亲本细胞和IAS诱导的CSC的芯片序列分析 发现组蛋白H3赖氨酸三甲基化（H3K4ME3）的富集大幅增加 基因转录的活性表观遗传标记，在对干性和糖酵解至关重要的基因中 CSC。了解IAS如何影响这些代谢和表观遗传学变化以及 CSC的产生，我们最近还研究了IAS在NRF2和 HIF1通过生化和CHIP-SEQ方法发出信号。数据表明NRF2和 HIF1可以用作代谢和表观遗传重编程的发起人，并获得了习得 CSC功能。彼此之间，我们假设IAS激活的NRF2是HIF1的上游激活因子 与糖酵解有关的信号传导以及随后的表观遗传重编程和生成 CSC。为了检验这一假设，将追求以下三个特定目标：AIM1，剖析NRF2 激活途径着重于IAS引起的泛素化和降解Keap1， NRF2的内源性抑制剂； AIM 2，研究HIF1的NRF2依赖性计划的机制 响应IAS的细胞中的信号传导；和目标3，了解IAS诱导的NRF2-HIF1如何 信号传导将代谢从线粒体TCA循环转移到与重编程有关的糖酵解 组蛋白甲基化谱和CSC的产生。我们希望来自 该研究计划的完成将是第一个揭示NRF2和HIF1在IAS中的重要性 - 诱导的CSC，可以通过靶向NRF2-来转化为癌症治疗的新策略 HIF1信号和CSC。