Genetic and Dietary Interactions in MMR Deficient Colon Tumorigenesis

MMR 缺陷性结肠肿瘤发生中的遗传和饮食相互作用

• 批准号: 10405006
• 负责人: LEONARD H AUGENLICHT
• 金额: $ 59.58万
• 依托单位: ALBERT EINSTEIN COLLEGE OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-07-05 至 2024-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10405006
• 关键词: ATAC-seq; Address; Back; Benign; CRISPR/Cas technology; Carcinoma; Cells; Characteristics; Chromatin; Chromatin Structure; Clinical; Collaborations; Colon; Colonic Adenoma; Colonic Neoplasms; Colorectal Cancer; Critiques; DNA; DNA Repair; Data; Databases; Defect; Detection; Development; Diet; Dietary Factors; Dissection; Early Diagnosis; Engineering; Epidemiology; Epigenetic Process; Epithelial Cells; Etiology; Gene Expression; General Population; Genes; Genetic; Genetic Models; Hereditary Nonpolyposis Colorectal Neoplasms; Histopathology; Homeostasis; Human; Incidence; Individual; Inherited; Intake; Intestinal Neoplasms; Intestines; Link; Mismatch Repair; Modeling; Modification; Molecular; Mucinous; Mucous Membrane; Mus; Mutation; Nutrient; Oligonucleotides; Oxidative Phosphorylation; Pathogenesis; Pathology; Pathway interactions; Patients; Penetrance; Prevention; Prevention strategy; Public Health; Publishing; Relative Risks; Risk; Risk Marker; Rodent; Sentinel; Site; Small Intestinal Neoplasm; Societies; Somatic Mutation; Specificity; Stomach; Stretching; Time; Tissues; Transforming Growth Factor beta; WNT Signaling Pathway; Wild Type Mouse; Work; adenoma; base; beta catenin; colon tumorigenesis; design; dietary; dietary control; exome sequencing; feeding; genome-wide analysis; histone modification; individualized medicine; mouse genetics; mouse model; novel; response; stem cell function; stem cell population; stem cells; transcriptome sequencing; tumor; tumorigenesis; villin; western diet

Mouse genetic models of Lynch syndrome (LS)/defective MMR (dMMR) driven tumorigenesis produce small intestinal tumors. However, long-standing collaborative work of the Co-PIs has now developed a new mouse model that causes LS/dMMR tumorigenesis in the mouse colon by integrating the genetic and environmental etiology that mimics that of the human. In the Villin-cre, Msh2loxp/loxp, TgfbRIIhu/hu mice (VMshThu), homozygous inactivation of Msh2 in intestinal and colonic epithelial cells causes tissue tissue-specific dMMR. Further, “G” residues in an otherwise “A” stretch in the mouse TgfbRll gene were altered by CRISPR/Cas9 to be oligoA, replicating the oligoA in the human gene that makes TgbRll a key target of dMMR. The mice develop intestinal tumors with the unique histopathologies of flat adenoma progressing to mucinous invasive carcinoma characteristic of LS/dMMR tumors, and every tumor has a mutation in the oligo A of the “humanized” TgfbRII gene. Feeding a purified rodent western-style diet (NWD1) to VMshThu mice shifts tumor penetrance into the colon, producing the same unique pathologies as in human LS/dMMR. The NWD1 recapitulates intake for the mouse of several nutrients at levels of each epidemiologically linked in western-societies to higher incidence of colorectal cancer. This new model has very high relevance to human LS, including historical data linking dietary shift in human LS to colon penetrance, as well as for somatically linked dMMR and sporadic colon tumorigenesis in the general population. Our published and submitted data establish that feeding NWD1 to wild-type mice profoundly alters function of intestinal stem cells in homeostasis and tumorigenesis, with underlying changes in stem cell programming and accumulation, spectra and signature of mutations. Therefore, we hypothesize shift to colon tumor penetrance by feeding NWD1 to VMshThu mice is due to altered colonic stem cell function. Aim 1 dissects alterations in function, programming, epigenetic and genetic changes induced by NWD1 in VMshThu mice in Lgr5hi, Bmi1+ and Aldh1+ colonic stem cell populations. Emphasis is on the Tgfb, Wnt signaling, DNA repair and oxidative phosphorylation pathways, and extended globally. Aim 2 addresses the fundamental public health issue of persistence of specific programming, epigenetic and genetic changes in long-lived colonic stem cells and their progeny upon switching the protumorigenic NWD1 back to purified control diet. Aim 3 dissects molecular changes that characterize the progression of the unique benign flat adenomas to mucinous invasive carcinomas. Further, using unique RNAseq data bases of LS patients compared to average risk individuals for the uninvolved mucosa, and for adenomas and carcinomas of LS and dMMR patients, correspondence between genes and pathways in the mouse model and in human will be determined. This will prioritize targets for development of markers of risk and progression and for further mechanistic dissection.

林奇综合征 (LS)/缺陷 MMR (dMMR) 驱动的肿瘤发生的小鼠遗传模型产生小 然而，Co-PI 的长期合作现已开发出一种新的小鼠。 通过整合遗传和环境导致小鼠结肠 LS/dMMR 肿瘤发生的模型 在 Villin-cre、Msh2loxp/loxp、TgfbRIIhu/hu 小鼠 (VMshThu) 中，纯合子的病因学。 肠和结肠上皮细胞中 Msh2 的失活会导致组织特异性 dMMR。 小鼠 TgfbRll 基因中“A”片段中的残基被 CRISPR/Cas9 改变为oligoA， 复制人类基因中的oligoA，使TgbRll成为dMMR的关键目标。小鼠发育出肠道。 具有扁平腺瘤进展为粘液浸润性癌的独特组织病理学的肿瘤 LS/dMMR 肿瘤的特征，每个肿瘤在“人源化”TgfbRII 的寡核苷酸 A 中都有突变 给 VMshThu 小鼠喂食纯化的啮齿动物西式饮食 (NWD1) 可将肿瘤外显率转变为 结肠，产生与人类 LS/dMMR 相同的独特病理学。 在西方社会，小鼠摄入多种营养素水平的流行病学与较高的发病率有关 这个新模型与人类 LS 具有非常高的相关性，包括与饮食相关的历史数据。 人类 LS 向结肠外显率的转变，以及与体细胞相关的 dMMR 和散发性结肠肿瘤发生 在一般人群中。 我们发表和提交的数据表明，给野生型小鼠喂食 NWD1 会深刻改变 肠道干细胞在稳态和肿瘤发生中的作用，以及干细胞编程和肿瘤发生的潜在变化 因此，我们转向结肠肿瘤外显率。 通过给 VMshThu 小鼠喂食 NWD1 是由于结肠干细胞功能的改变。目的 1 剖析了结肠干细胞功能的改变。 VMshThu 小鼠 Lgr5hi、Bmi1+ 中 NWD1 诱导的功能、编程、表观遗传和遗传变化 和 Aldh1+ 结肠干细胞群 重点是 Tgfb、Wnt 信号传导、DNA 修复和氧化。 目标 2 解决了基本的公共卫生问题。 长寿结肠干细胞及其中特定编程、表观遗传和遗传变化的持续存在 将促肿瘤 NWD1 转回纯化对照饮食后的后代 Aim 3 剖析了分子。 独特的良性扁平腺瘤进展为粘液侵袭性特征的变化 此外，使用 LS 患者的独特 RNAseq 数据库与平均风险个体进行比较。 未受累粘膜，对于 LS 和 dMMR 患者的腺瘤和癌，之间的对应关系 小鼠模型和人类中的基因和通路将被确定，这将确定优先目标。 开发风险和进展标记并进行进一步的机械解剖。