Colibactin-Producing Escherichia coli as an Environmental Stimulus Shaping Pre-Cancer Progression

产生大肠杆菌素的大肠杆菌作为塑造癌症前期进展的环境刺激物

• 批准号: 10697373
• 负责人: Martha J. Shrubsole
• 金额: $ 29.94万
• 依托单位: VANDERBILT UNIVERSITY MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-09-15 至 2027-08-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10697373
• 关键词: Acceleration; Address; Adoption; Adverse event; Affect; Anesthesia procedures; Automobile Driving; Bacteroides fragilis; Biological Markers; Biological Specimen Banks; Biology; Cancer Etiology; Cells; Cessation of life; Characteristics; Collaborations; Colon; Colonic Neoplasms; Colonoscopy; Colorectal; Colorectal Cancer; DNA; Data; Data Set; Detection; Developed Countries; Development; Diet; Disease; Disease stratification; Ecosystem; Epidemiology; Epithelial Cells; Epithelium; Escherichia coli; Fostering; Gene Mutation; Genes; Genomics; Hand; Hemorrhage; Human; Immunofluorescence Immunologic; Individual; Indolent; Induced Mutation; Investigation; Lesion; Malignant - descriptor; Malignant Neoplasms; Modeling; Molecular; Mucous Membrane; Mutagens; Mutate; Mutation; Neoplasms; Obesity; Pathogenesis; Pathway interactions; Perforation; Persons; Polypectomy; Polyps; Prevention; Prevention strategy; Public Health; Publishing; Recommendation; Reporting; Risk; Risk Factors; Science; Seminal; Shapes; Smoking; Stimulus; Testing; Time; United States; Virulence; Woman; adenoma; burden of illness; carcinogenesis; clinical predictors; cohort; colon carcinogenesis; colon microbiota; colorectal cancer risk; colorectal cancer screening; cost effective; design; early onset; exome sequencing; human data; improved; improved outcome; lifetime risk; longitudinal design; men; microbial; microbiome; microbiota; molecular marker; polyketide synthase; premalignant; risk stratification; screening; single-cell RNA sequencing; uptake

Sporadic colorectal cancer (CRC) is a public health problem, affecting over a million people each year globally and, in the United States, consistently ranks in the top 2-3 causes of cancer-related death in men and women despite the wide adoption of colonoscopy. Metachronous pre-cancers are also high following polypectomy. However, only a small percent of colon pre-cancers (conventional adenomas or sessile serrated lesions) progress to CRC, and we lack both molecular markers to identify these individuals and an understanding of the mechanisms fostering pre-cancer. The large disease burden of CRC, co-localized with the densely populated colon microbiota, and the recognition that many CRC risk factors (e.g., smoking, obesity, carnivorous diet) modify the colon microbiota has spurred investigations into ‘if and how’ the microbiota contributes to CRC pathogenesis. Accrued data now strongly support the hypothesis that the microbiota is a key environmental contributor to colon carcinogenesis. Nonetheless, little is yet known about ‘if and how’ the microbiota contributes to colon pre- cancers. Our preliminary data identify Escherichia coli that release the non-ribosomal, metabolite genotoxin, colibactin, known as pks+ E. coli (Ecpks), as strongly associated with detection of colon pre-cancers. Further, colibactin is reported to induce specific mutational signatures in colon epithelial cell DNA, in particular, mutations in APC, a CRC driver gene particularly important in adenoma development. Notably, these Ecpks mutations have been associated with CRC. In our COLON MAP study, we have also identified that sessile serrated lesions which account for a large proportion of interval CRC, are likely a result of microbial insult. However, it remains unknown whether Ecpks contributes to SSL development and progression. The few previous human studies, including our preliminary studies, are based on a cross-sectional design. Thus, to address this gap and understand the temporal sequence, we will also include a longitudinal design and human colonoids models to test our core hypothesis that a subset of Ecpks associate with and contribute to driving human pre-cancer progression. We will use a wide array of iterative approaches and conceptual and experimental integration of this project with Projects 1 and 3 and the cores of this U54. Our specific aims in this translational project are: 1) To evaluate the association of Ecpks colonization with human colorectal pre-cancers with greater progressive vs. lower (“indolent”) potential using in-hand human cohorts, clinical predictors, and longitudinal data; 2) To examine mechanisms associated with pre-cancer colon lesions stratified by disease state (indolent or progressive) and Ecpks status using whole exome sequencing, single cell RNAseq and multiplex immunofluorescence (MxIF) approaches; and 3) To identify Ecpks virulence determinants associated with progressive (vs indolent) colon pre-cancer and disease mechanisms using human colonoid models. Together, our studies have the potential to accelerate noninvasive, cost-effective CRC screening and surveillance for a critical subset of individuals at increased risk for sporadic CRC.

散发性结直肠癌(CRC)是一个公共卫生问题，每年影响全球100多万人。 在美国，男性和女性因癌症而死亡的原因一直排在前2-3位 尽管结肠镜检查被广泛采用。息肉切除术后异时性癌前病变的发生率也很高。 然而，只有一小部分结肠癌前病变(传统性腺瘤或固有性锯齿状病变) CRC的进展，我们既缺乏识别这些个体的分子标记，也缺乏对 孕育癌前病变的机制。结直肠癌巨大的疾病负担，与人口稠密的人同处一地 结肠微生物区系，以及对许多结直肠癌危险因素(如吸烟、肥胖、食肉饮食)修改的认识 结肠微生物区系促进了对微生物区系是否以及如何促进CRC发病机制的研究。 现在积累的数据有力地支持了这样的假设，即微生物区系是结肠的关键环境贡献者 致癌。尽管如此，关于微生物区系是否以及如何对结肠前收缩做出贡献的信息还知之甚少。 癌症。我们的初步数据确定了释放非核糖体、代谢物基因毒素的大肠杆菌， Colibactin，即PKS+E.Coli(ECPKS)，与检测结肠癌前病变密切相关。此外， 据报道，Colibactin可以在结肠上皮细胞DNA中诱导特定的突变特征，特别是突变 在APC中，一种在腺瘤发展中特别重要的CRC驱动基因。值得注意的是，这些ecpks突变 都与儿童权利公约有关联。在我们的结肠映射研究中，我们还发现了无梗锯齿状病变 它们在间歇性CRC中占很大比例，很可能是微生物侮辱的结果。然而，它仍然 不知道ECPKS是否有助于SSL的发展和进步。之前为数不多的人体研究， 包括我们的初步研究，都是基于横断面设计。因此，为了解决这一差距，并 了解时间序列，我们还将包括纵向设计和人类结肠腺模型 测试我们的核心假设，即ECPK的子集与人类癌前病变相关并有助于推动人类癌前病变 进步。我们将使用广泛的迭代方法以及概念和实验集成 这个项目包括项目1和项目3，以及这架U54的核心。我们在这个翻译项目中的具体目标是：1) 评估ECPK定植与进展较快的人类结直肠癌前病变的关系 使用现有的人类队列、临床预测者和纵向数据对比较低的(“惰性”)潜力；2) 检查与癌前病变相关的机制，按疾病状态分层(惰性或 利用整个外显子组测序、单细胞RNAseq和多重技术检测ECPK状态 免疫荧光(MxIF)方法；以及3)鉴定与ECPK毒力相关的决定因素 使用人类结肠模型的进行性(vs.惰性)结肠癌前病变和疾病机制。一起， 我们的研究有可能加速无创、经济高效的结直肠癌筛查和监测 散发性结直肠癌风险增加的关键人群。