Mechanisms of Dynamic Transcriptional Reprogramming in Metastasis Stem Cells

转移干细胞动态转录重编程的机制

• 批准号: 10577727
• 负责人: Karuna Ganesh
• 金额: $ 39.68万
• 依托单位: SLOAN-KETTERING INST CAN RESEARCH
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-03-01 至 2027-01-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10577727
• 关键词: 3' Untranslated Regions; Acceleration; Adherens Junction; Advanced Malignant Neoplasm; Binding; Binding Proteins; Biochemical; Biological Assay; Biological Models; Cancer Etiology; Cell Cycle; Cells; Cessation of life; Chromatin; Clinical; Colitis; Colon; Colorectal Cancer; Complex; Cytoplasmic Granules; Data; Development; Disseminated Malignant Neoplasm; Distant; E-Cadherin; Elements; Engineering; Epigenetic Process; Epithelial Cells; Epithelium; Family; Fluorescence; Gene Expression; Genes; Genetic; Genetic Transcription; Homeostasis; Immunofluorescence Immunologic; Immunoprecipitation; Impairment; Injections; Intestinal Neoplasms; Intestines; Invaded; Knock-in; LGR5 gene; Maintenance; Malignant Neoplasms; Mediating; Mediator; Messenger RNA; Modeling; Molecular; Mutation; Natural regeneration; Neoplasm Metastasis; Neural Cell Adhesion Molecule L1; Neurons; Neurosecretory Systems; Oncogenes; Organ; Organoids; Outcome; Output; Patient-Focused Outcomes; Patients; Phase; Phenotype; Physiologic pulse; Physiological; Primary Neoplasm; Proliferating; Proteins; RNA; RNA-Binding Proteins; Rectum; Recurrence; Regulation; Reporter; Resistance; Role; Sampling; Stress; Structure; Structure of splenic vein; Time; Tissues; Tumor Suppressor Proteins; Untranslated Regions; Work; Xenograft procedure; cancer cell; cancer initiation; cancer stem cell; colorectal cancer metastasis; crosslink; derepression; in vivo; insight; intestinal epithelium; knock-down; mRNA Transcript Degradation; member; mouse model; neoplastic; neuroendocrine differentiation; novel; overexpression; posttranscriptional; progenitor; programs; protein complex; rectal; regenerative; regenerative cell; repaired; response; restoration; self-renewal; single cell mRNA sequencing; stem cell self renewal; stem cells; stemness; therapeutic target; therapy outcome; tissue regeneration; transcriptional reprogramming; transcriptome sequencing; transcriptomics; tumor; tumor initiation; tumor progression; whole genome; wound healing

Metastasis causes >90% of cancer death. The persistence and lethality of metastasis is driven by cells capable of self-renewal, slow cell-cycling, tumor re-initiation, and therapy resistance, termed metastasis stem cells (MetSCs). Development of effective strategies for eliminating metastasis requires a better understanding of the mechanisms that MetSCs exploit for survival. We recently demonstrated that (1) disseminating colorectal cancers (CRC) undergo a dynamic phenotypic switch from an LGR5+ tumor-initiating cancer stem cell (CSC) state to a distinct LGR5lowL1CAM+ state required for metastasis. (2) This phenotypic plasticity of MetSCs is retained in ex vivo patient derived organoids, which can be used to dissect mechanisms of plasticity. (3) L1CAM+ MetSCs are functionally distinct from intestinal tumor-initiating LGR5+ CSCs: L1CAM is required for organoid formation, the regeneration of intestinal epithelium after colitis, and tumor formation after metastatic dissemination. But unlike LGR5, it is dispensable for epithelial homeostasis or intestinal tumor initiation. In contrast to tumor initiation, where homeostatic stem cells undergo oncogene-driven hyper proliferation in intact tissues, metastasis subverts a regenerative mechanism to survive and regrow outside an intact epithelial niche. (4) We have shown that the principal driver of L1CAM expression is loss of epithelial integrity itself, acting via loss of E-cadherin intercellular adherens junctions to transiently displace the transcriptional silencer REST/NSRF from chromatin in quiescent MetSCs, in turn derepressing expression of L1CAM and other genes required for tissue regeneration1. Proliferation, restoration of epithelial structures, and macrometastatic outgrowth, on the other hand, require high REST levels. Our evidence suggests that MetSCs cells are regenerative stem cells that emerge directly in response to loss of epithelial integrity to drive repair, a phenotype of physiological wound healing that is redeployed in MetSCs. In this proposal, we will define the molecular mechanism by which REST chromatin binding is dynamically regulated in MetSCs, and how this in turn enables cell fate plasticity from stemness to proliferation. Our preliminary data implicates the mRNA binding protein ZFP36L1/2 in REST- mediated metastatic plasticity. Project hypothesis: The ZFP36L1/2REST axis is a master regulator of cell fate plasticity in intestinal epithelial progenitors. Aim 1: Define the function of the ZFP36L1/2-REST axis in normal and neoplastic intestinal stem cell self-renewal, differentiation, and proliferation. Aim 2: Dissect the molecular mechanism of ZFP36L1/2-mediated cell fate plasticity. Aim 3: Determine the functional consequences of ZFP36L1/2-REST dynamic regulation in metastatic seeding and colonization. Results will define mechanisms of cancer progression and identify putative therapeutic targets to limit regenerative plasticity, with potential to impact clinical outcomes.

90%的癌症死亡是由转移引起的。转移的持久性和致命性是由能够 自我更新、细胞周期缓慢、肿瘤重新启动和治疗耐药的一部分，称为转移干细胞 (MetSCs)。开发有效的消除转移的策略需要更好地了解 金属间充质干细胞赖以生存的机制。我们最近证明：(1)传播结直肠 肿瘤(CRC)经历LGR5+肿瘤起始肿瘤干细胞(CSC)的动态表型转换 状态为转移所需的独特LGR5lowL1CAM+状态。(2)MetSCs的这种表型可塑性是 保留在体外患者衍生的有机类化合物，可用于剖析可塑性的机制。(3)L1CAM+ 间质干细胞在功能上不同于启动肠道肿瘤的LGR5+CSCs：有机类细胞需要L1CAM 结肠炎后肠上皮的形成、再生和转移后的肿瘤形成 传播。但与LGR5不同的是，它对于上皮内稳态或肠道肿瘤的启动是必不可少的。在……里面 与肿瘤启动相反，在肿瘤启动过程中，体内平衡干细胞在完整的体内经历癌基因驱动的过度增殖 组织，转移颠覆了一个再生机制，在一个完整的上皮生态位外生存和再生。 (4)我们已经证明L1CAM表达的主要驱动因素是上皮完整性本身的丧失，通过 E-钙粘附素的细胞间黏附连接瞬间取代转录沉默因子REST/NSRF 从静止的MetSCs中的染色质，进而降低L1CAM和其他基因的表达 组织再生1。上皮结构的增殖、修复和大转移性生长。 另一方面，需要较高的休息水平。我们的证据表明，骨髓间充质干细胞是再生干细胞， 直接出现对上皮完整性丧失的反应以驱动修复，这是一种生理性伤口的表型 在MetSCs中重新部署的修复。在这个提案中，我们将定义休息的分子机制 染色质结合在MetSCs中动态调节，以及这如何反过来使细胞命运可塑性从 从茎到增殖。我们的初步数据表明，mRNA结合蛋白ZFP36L1/2在REST- 转移性可塑性。项目假设：ZFP36L1/2REST轴是细胞命运的主要调节者 肠上皮祖细胞的可塑性。目标1：定义ZFP 36L1/2-Rest轴在正常状态下的功能 和肿瘤肠道干细胞的自我更新、分化和增殖。目标2：剖析分子 ZFP36L1/2介导的细胞命运可塑性机制。目标3：确定以下各项的功能后果 ZFP36L1/2-REST在转移种植和定植中的动态调节结果将定义 癌症进展和确定假定的治疗靶点以限制再生可塑性，具有潜在的 影响临床结果。