Role of Sox2 in stomach development, regeneration and cancer

Sox2 在胃发育、再生和癌症中的作用

基本信息

批准号：
8348185
负责人：
Konrad Hochedlinger
金额：
$ 35.32万
依托单位：
MASSACHUSETTS GENERAL HOSPITAL
依托单位国家：
美国
项目类别：
财政年份：
2012
资助国家：
美国
起止时间：
2012-07-01 至 2016-06-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8348185
关键词：
Ablation Address Adenocarcinoma Adult Alleles Antral Biochemical Biology Cancer Etiology Cause of Death Cells Cessation of life Chief Cell Complement Development Diffuse Doxycycline E-Cadherin Electron Microscopy Embryo Epithelial Epithelium Evaluation Exhibits Fetal Development Gastric Parietal Cells Gene Expression Profile Genes Genetic Goals Homeostasis Human In Vitro Inflammation Injury Interferons Intestines Kinetics Location Malignant - descriptor Malignant Neoplasms Maps Messenger RNA MicroRNAs Modeling Molecular Molecular Target Mus Mutagenesis Mutate Natural regeneration Oncogenic Organoids Pathway interactions Pattern Phenotype Play Predisposition Process Proteins Pylorus Qualifying Regenerative Medicine Reporter Reporting Role Signal Transduction Staging Stem cells Stimulus Stomach System Testing Tissues Transgenic Organisms Tumor Suppressor Genes Tumor Suppressor Proteins United States adenoma adult stem cell base cancer prevention cancer therapy cell injury cell type cellular targeting chemical genetics gain of function in vivo insight loss of function malignant stomach neoplasm mouse model novel overexpression postnatal prenatal progenitor repaired research study response self-renewal stem stem cell differentiation stem cell niche tool tumor tumor initiation tumorigenesis villin

项目摘要

DESCRIPTION (provided by applicant): The stomach epithelium comprises two main compartments with distinct turnover rates and cell compositions termed antrum or pylorus and corpus or main body. While classical mutagenesis experiments suggested the existence of adult stem cells that continuously replenish these cell types, their identity and localization remains elusive. Notably, a recent report identified Lgr5+ stem cells in the antrum, which are capable of multilineage differentiation over long-term and can serve as the cell type of origin for adenomas upon deletion of the tumor suppressor gene Apc. We have recently identified rare Sox2+ cells in the antrum and corpus of mice. Genetic lineage tracing demonstrates that Sox2+ cells can, like antral Lgr5+ cells, give rise to all mature cell types in the stomach for up to 22 months, thus qualifying as bona fide stem cells. These observations raise the following key questions relevant to the biology of stomach turnover and stomach cancer: (1) When in development are Sox2+ stomach stem cells formed; (2) Are Sox2+ stem cells and Lgr5+ stem cells part of the same lineage; (3) What are the molecular and cellular features of Sox2+ stem cells in antrum and corpus; (4) Do Sox2+ stem cells divide symmetrically or asymmetrically and at which rate; (5) Are Sox2+ stem cells responsive to tissue injury and inflammation; (6) Are Sox2+ cells more amenable to tumorigenesis than differentiated stomach cells; and (7) Is Sox2 itself required for stomach development, tissue homeostasis and cancer? We have developed several novel transgenic tools in mice to address each of these fundamental questions in the context of three major aims and multiple subaims. Specifically, we have generated Sox2-GFP reporter mice as well as Sox2-CreER lineage tracing mice to characterize Sox2+ cells at the molecular and cellular levels at different stages of development. Aim 1 entails characterization of the ultrastructure and transcriptome of Sox2+ cells as well as their self-renewal and differentiation kinetics, establishment of an in vitro culture system and evaluation of the lineage relationship between Sox2+ cells and Lgr5+ cells. In Aim 2, we will cross a novel conditional allele for Sox2 to different Cre drivers to assess the requirement for Sox2 at various stages of pre-and postnatal development and in the context of stomach cell injury inflicted by several genetic and chemotoxic models. Given that stomach cancer is the second-most common cause of cancer-related deaths worldwide with relatively little known about its underlying genetic and cellular origins, we propose to test in Aim 3 the susceptibility of Sox2+ stem cells to malignant transformation. Here, we will evaluate whether Sox2+ stem cells are amenable to transformation into adenomas/adenocarcinomas upon deletion of the Apc tumor suppressor and whether Sox2 protein itself is required for tumor formation. Lastly, we will test the hypothesis that the differentiation state of stomach cells influences their amenability to transformation by deleting the E-Cadherin gene, which is mutated in 50% of human diffuse gastric cancer cases, in Sox2+ stem cells, transit-amplifying cells and differentiated chief cells. PUBLIC HEALTH RELEVANCE: Stomach cancer is the second-most common cancer-related cause of death worldwide with an increase seen specifically in diffuse gastric cancer in the United States. Elucidating the fundamental biology of stomach development and homeostasis is imperative for understanding how stomach cancer develops and for identifying cellular and molecular targets for treatment. Thus, by studying Sox2 and Sox2+ stem cells in the normal and malignant stomach, we will gain new basic insights that can be exploited for regenerative medicine as well as for stomach cancer prevention and treatment.

描述（由申请人提供）：胃上皮包括两个主要的隔室，其周转率不同，细胞组成称为胸骨，幽门，幽门和科体或主体。尽管经典诱变实验表明存在不断补充这些细胞类型的成年干细胞的存在，但它们的身份和定位仍然难以捉摸。值得注意的是，最近的一份报告确定了肌酸中的LGR5+干细胞，可以长期进行多素分化，并在缺失肿瘤抑制基因APC后作为腺瘤的细胞来源类型。我们最近已经确定了小鼠粪便和语料库中的稀有Sox2+细胞。遗传谱系跟踪表明，Sox2+细胞可以像胃肠道LGR5+细胞一样，在长达22个月内会产生胃中所有成熟的细胞类型，从而成为真正的干细胞。这些观察结果提出了以下关键问题，这与胃更新和胃癌的生物学有关：（1）当发育中是SOX2+胃干细胞时；（2）是Sox2+干细胞和同一谱系的LGR5+干细胞一部分；（3）Sox2+干细胞在鼻和语料库中的分子和细胞特征是什么？（4）DO Sox2+干细胞对称或不对称地分裂；（5）是Sox2+干细胞，对组织损伤和炎症有反应；（6）是Sox2+细胞比分化的胃细胞更适合肿瘤发生；（7）Sox2本身是否需要胃，组织稳态和癌症？我们已经在小鼠中开发了几种新型的转基因工具，可以在三个主要目标和多个Subiaims的背景下解决这些基本问题。具体而言，我们已经生成了SOX2-GFP报告基因小鼠以及Sox2-Creer谱系追踪小鼠，以在不同发育阶段在分子和细胞水平上表征Sox2+细胞。 AIM 1需要表征Sox2+细胞的超微结构和转录组以及它们的自我更新和分化动力学，建立体外培养系统以及评估SOX2+细胞和LGR5+细胞之间的谱系关系。在AIM 2中，我们将跨越Sox2的新有条件等位基因到不同的CRE驱动因素，以评估产后和产后发育的各个阶段的Sox2的需求，以及在几种遗传和化学毒性模型造成的胃细胞损伤的背景下。鉴于胃癌是全球与癌症相关死亡的第二常见原因，对其潜在的遗传和细胞起源鲜为人知，我们建议在AIM 3中测试SOX2+干细胞对恶性转化的敏感性。在这里，我们将评估SOX2+干细胞是否可以在缺失APC肿瘤抑制器后转化为腺瘤/腺癌，以及SOX2蛋白本身是否需要肿瘤形成。最后，我们将检验以下假设：胃细胞的分化状态通过删除e-Sox2+干细胞中50％的人类弥漫性胃癌病例中50％的E-钙粘着蛋白基因来影响其转化性，该基因在50％的人类弥漫性胃癌病例中突变。分化的主要细胞。公共卫生相关性：胃癌是全世界与癌症相关的第二个常见死亡原因，在美国的弥漫性胃癌中特别有所增加。阐明胃发育和稳态的基本生物学对于了解胃癌的发展以及鉴定细胞和分子靶标的治疗至关重要。因此，通过研究正常和恶性胃中的Sox2和Sox2+干细胞，我们将获得可用于再生医学以及预防胃癌的新基本见解。