Molecular analysis of intestinal stem cells in the context of premature aging, chronic inflammation and colorectal carcinogenesis

过早衰老、慢性炎症和结直肠癌发生背景下肠道干细胞的分子分析

• 批准号: 251130357
• 负责人: Dr. Sebastian Försch
• 金额: --
• 依托单位: Leibniz-Institut für Alternsforschung - Fritz-Lipmann-Institut e.V. (FLI)
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2014
• 资助国家: 德国
• 起止时间: 2013-12-31 至 2014-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/251130357?language=en
• 关键词: Molecular; analysis; intestinal; stem; cells

Colorectal cancer is one of the most common tumors in industrialized countries and associated with a high morbidity and mortality. Especially elderly patients and patients with inflammatory bowel disease have an increased risk to develop colorectal cancer. As cellular origin of tumorigenesis intestinal stem cells that express the so-called leucine-rich repeat-containing G-protein-coupled receptor 5 (Lgr5) recently moved into the scientific focus. The effects of aging and chronic inflammation on intestinal stem cells are still largely unknown and will be investigated in this research project.Animal models of chronic inflammation and premature aging will be combined with an Lgr5 model. Telomerase-deficient animals with dysfunctional telomeres will serve as an aging model. Animals after chemically-induced chronic colitis (DSS colitis) will serve as an inflammation model. Lgr5-positive intestinal stem cells are isolated from the animals of these models and respective control groups. Then the project will be divided into three parts: (I) The isolated intestinal stem cells, will be analyzed using next-generation sequencing (NGS) to identify genetic differences in tumor-associated signaling pathways. In this examination, prematurely-aged, chronically-inflamed and healthy stem cells will be compared. NGS analysis will be used to identify candidate genes, which have a positive or negative effect on growth, survival and proliferation of intestinal stem cells. (II) The next step will be the creation of specific shRNAs for these candidate genes and their effect on Lgr5-positive intestinal stem cells will be examined in vitro. Gene knockdowns, which lead to an increase in growth and survival of intestinal stem cells in vitro, will be used to produce genetically modified intestinal organoids. (III) These intestinal organoids will be transplanted into healthy animals in order to investigate the influence of aging and chronic inflammation on engraftment, differentiation and colorectal carcinogenesis in vivo.

结直肠癌是工业化国家最常见的肿瘤之一，具有较高的发病率和死亡率。特别是老年患者和炎症性肠病患者患结直肠癌的风险增加。作为肿瘤发生的细胞来源，表达富含亮氨酸重复序列的G蛋白偶联受体5（Lgr5）的肠干细胞最近成为科学研究的焦点。衰老和慢性炎症对肠道干细胞的影响在很大程度上仍然是未知的，将在本研究项目中进行研究。慢性炎症和过早衰老的动物模型将与Lgr 5模型相结合。端粒功能失调的端粒酶缺陷动物将作为衰老模型。化学诱导的慢性结肠炎（DSS结肠炎）后的动物将用作炎症模型。从这些模型和相应对照组的动物中分离lgr 5阳性肠干细胞。然后，该项目将分为三个部分：（一）分离的肠道干细胞，将使用下一代测序（NGS）进行分析，以确定肿瘤相关信号通路的遗传差异。在这项检查中，将比较早熟，慢性炎症和健康的干细胞。NGS分析将用于鉴定对肠干细胞的生长、存活和增殖具有积极或消极影响的候选基因。(II)下一步将是为这些候选基因创建特异性shRNA，并将在体外检查它们对Lgr5阳性肠干细胞的影响。基因敲除，导致体外肠干细胞的生长和存活增加，将用于生产基因修饰的肠类器官。(III)将这些肠类器官移植到健康动物体内，以研究衰老和慢性炎症对体内移植、分化和结直肠癌发生的影响。