Probing cytosolic nucleic acid sensing pathways in cancer

探索癌症中的胞质核酸传感途径

基本信息

批准号：
10321271
负责人：
Samuel F Bakhoum
金额：
$ 70.46万
依托单位：
WEILL MEDICAL COLL OF CORNELL UNIV
依托单位国家：
美国
项目类别：
财政年份：
2021
资助国家：
美国
起止时间：
2021-01-01 至 2025-12-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10321271
关键词：
Antitumor Response Back Biological Assay Breast Cancer Model Bypass CXCL10 gene Cell Differentiation process Cell Shape Cells Chromosomal Instability Chronic Clustered Regularly Interspaced Short Palindromic Repeats Cytoplasm Cytosol DNA Data Dependence Development Double-Stranded RNA Embryonic Development Epithelial Gene Silencing Gene Targeting Genes Genetic Transcription Genetically Engineered Mouse Genomic Instability Immune Immune response Immune system Immunotherapy In Vitro Inflammation Inflammation Mediators Inflammatory Inflammatory Response Interferon Type I Interferons Knock-out Link Logic Malignant Neoplasms Malignant neoplasm of lung Mammalian Cell Maps Mediating Mediator of activation protein Medicine Mus Mutagenesis Nature Neoplasm Metastasis Normal Cell Nucleic Acids Output Pathway interactions Phenotype Predisposition Process Production Reporter Resistance Role STING agonists STING1 gene Signal Transduction Source Stimulator of Interferon Genes Stimulus System Testing Therapeutic Thinking Transplantation Tumor Immunity Viral Work anti-tumor immune response autoinflammatory cancer cell cancer cell differentiation combinatorial cytokine ds-DNA early phase clinical trial experimental study genetic manipulation immune activation immune checkpoint blockade immune resistance in vivo innate immune pathways interest man mouse model neoplastic cell novel pancreatic cancer model progenitor programs receptor resistance mechanism response sensor single cell sequencing stem stem cells synergism therapeutically effective therapy development tissue regeneration transcription factor tumor tumor heterogeneity vector wound healing

项目摘要

ABSTRACT The ability of mammalian cells to elicit inflammation is central to many processes including embryogenesis, wound healing, tissue regeneration, and cancer metastasis. A major source of inflammatory signaling is the aberrant presence of double-stranded (ds) nucleic acids in the cytoplasm. Mammalian cells have evolved high- ly conserved mechanisms to detect cytosolic nucleic acids as an anti-viral defense. In normal cells, cGAS (cy- clic GMP-AMP synthase) and its downstream signaling effector STING (stimulator of interferon genes) have been proposed as essential mediators of type I interferon (IFN) signaling and downstream immune activation. We have shown however, that in cancer cells with chromosomal instability (CIN), there is no evidence of type I IFN signaling despite the presence of cytosolic DNA and constitutive activation of cGAS and STING. Instead, cancer cells rewire their signaling downstream of STING to selectively suppress IFN signaling and enable oth- er pro-metastatic pathways such as NF-κB. Three important pieces of evidence bring into question the essen- tiality of the cGAS-STING pathway in promoting anti-tumor immunity and suggest heretofore unappreciated redundancies and context dependence of nucleic acid sensing in cancer: 1) chromosomally unstable cancer cells retain IFN-responsiveness to cytosolic dsRNA. 2) Cancer cells with CIN can still elicit a robust, anti-tumor immune response to cytosolic dsDNA, in a manner independent of cGAS-STING and type I IFN. 3) Expression of nucleic acid sensors and downstream inflammatory pathways is highly variable across tumor subpopulations and metastatic cell states – in which a continuum of stem-like to more committed epithelial progenitors is ob- served. Together, these findings challenge the current view that cGAS-STING signaling is the universal media- tor of inflammation in response to cytosolic dsDNA. Herein, we aim to understand functional redundancies and interactions across cytosolic nucleic acid sensing pathways and how their transcriptional outputs vary with tu- mor cell differentiation status. We will systematically interrogate key nucleic acid sensors and their downstream effectors in three syngeneic mouse models characterized by increased metastatic potential and high levels of CIN. We will experimentally manipulate CIN rates to identify cytosolic nucleic acid-dependent, but cGAS- STING-independent mechanisms of immune activation (Aim 1). We will then couple high-throughput single-cell sequencing with combinatorial CRISPR-mediated gene inactivation of key cytosolic nucleic acid sensors and effectors in metastasis-initiating stem cells distinguished by SOX2 expression, versus their more differentiated counterparts, to map the cell state-specific regulatory logic of this pathway (Aim 2). Unraveling the context- dependence of this extremely important and versatile signaling cascade has the potential to transform our thinking about chronic inflammation in cancer and to reveal therapeutic vulnerabilities in chromosomally unsta- ble cancer cells that are otherwise resistant to cGAS-STING signaling.

抽象的哺乳动物细胞引发炎症的能力是许多过程的核心，包括胚胎发生、伤口愈合、组织再生和癌症转移是炎症信号的主要来源。哺乳动物细胞的细胞质中异常存在双链（ds）核酸。在正常细胞中，cGAS（cy-）是检测胞质核酸作为抗病毒防御的保守机制。 clic GMP-AMP 合酶）及其下游信号效应器 STING（干扰素基因刺激器）已被提议作为 I 型干扰素 (IFN) 信号传导和下游免疫激活的重要介质。然而，我们已经证明，在具有染色体不稳定 (CIN) 的癌细胞中，没有证据表明 I 型尽管存在胞质 DNA 以及 cGAS 和 STING 的组成型激活，但 IFN 信号传导相反。癌细胞重新连接 STING 下游的信号传导，以选择性抑制 IFN 信号传导并启用其他功能呃促转移途径，例如 NF-κB，三个重要的证据对本质提出了质疑。 cGAS-STING 通路在促进抗肿瘤免疫方面的重要性，并表明迄今为止尚未得到重视癌症中核酸传感的冗余和背景依赖性：1）染色体不稳定的癌症细胞保留对胞浆 dsRNA 的 IFN 反应性 2) 具有 CIN 的癌细胞仍然可以引发强大的抗肿瘤作用。对胞质 dsDNA 的免疫反应，其方式独立于 cGAS-STING 和 I 型 IFN 3) 表达。核酸传感器和下游炎症途径的变化在肿瘤亚群中存在很大差异和转移细胞状态——其中干细胞样到更定向的上皮祖细胞的连续体是观察到的这些发现共同挑战了当前的观点，即 cGAS-STING 信号传导是通用媒体。在此，我们的目标是了解功能冗余和炎症反应。跨胞质核酸传感途径的相互作用以及它们的转录输出如何随tu-变化我们将系统地研究关键的核酸传感器及其下游。三种同基因小鼠模型中的效应子，其特征是转移潜力增加和高水平我们将通过实验操纵 CIN 率来识别胞质酸依赖性但 cGAS- 独立于 STING 的免疫激活机制（目标 1）然后我们将耦合高通量单细胞。通过组合 CRISPR 介导的关键胞质核酸传感器基因失活进行测序转移起始干细胞中的效应子通过 SOX2 表达来区分，与其分化程度更高的干细胞相比臂，绘制该通路的细胞状态特异性调控逻辑（目标 2）。这种极其重要且多功能的信号级联的依赖性有可能改变我们的思考癌症中的慢性炎症并揭示染色体不稳定的治疗脆弱性 ble 癌细胞，否则对 cGAS-STING 信号有抵抗力。