CMA: Cancer Stem Cells in the Pathogenesis and Treatment of Colorectal Cancer

摘要 该提案是作为全国退伍军人事务部一组相关绩效审查申请的一部分提交的 结直肠癌（CRC）专家组成了结直肠癌细胞基因组学联盟（VA 4C） 在2017年5月参加了在芝加哥举行的一次成功的实地会议（由VA ORD资助）后。 具体来说，这项建议将是一组价值审查项目的一部分，这些项目旨在推进我们的 了解CRC发病机制和治疗反应，重点是微生物组的作用， CRC干细胞。肠道微生物组对CRC的发展和进展的重要性是 由一系列证据支持，包括饮食和CRC风险之间的流行病学联系，可重复性 特定微生物如梭杆菌与人CRC的关联，小鼠模型表明 微生物群增加CRC形成和转移，小鼠模型显示， 微生物组调节化疗反应。我们假设：1）肠道微生物组，通过 肿瘤组织的直接侵袭和生物活性微生物产物的释放与特定的CRC相关 临床/组织学表型和由转录谱定义的分子亚类。2)肠 微生物组通过调节抗肿瘤药物影响手术和化疗后复发的风险 免疫和化疗药物的代谢。3)局部晚期结直肠癌的外科治疗 切除和化疗改变了肠道微生物组，这可能会影响未来的可能性。 反复发作。为了研究这些假设，在目标1中，我们将利用本研究的多中心临床基础设施， CMA将从400名患有I-III期CRC的男性和女性退伍军人中收集粪便和肿瘤样本进行分析 微生物组、代谢组和转录组。将鉴定肠道微生物和代谢物， 与肿瘤表型和分子特征相关，如由基因转录物、功能性 途径和非编码RNA。在目标2中，我们将对200名II期退伍军人进行纵向随访- III结直肠癌，以阐明预测随后复发风险的基线微生物和代谢物。 此外，我们将在手术前、手术中和手术后以及化疗后每年采集粪便样本 此后，以确定治疗过程中微生物的变化及其与未来复发的关系。在目标3中， 将通过使用C57 BL/6 ApcMin将肠道微生物组的组成和功能变化与CRC联系起来 对自发性肠腺瘤形成高度敏感的小鼠品系。我们会研究 用从具有高或低免疫浸润的患者获得的人微生物群定殖的效果， 免疫转录状态，以评估腺瘤/CRC形成和瘤内免疫应答。我们将 还研究了移植CRC细胞并用粪便定殖的小鼠对化疗的反应。 复发或持续缓解的患者，以评估微生物群介导的 治疗反应。

ABSTRACT This proposal is being submitted as part of a group of linked merit review applications from nationwide VA experts in colorectal cancer (CRC) who have formed a colorectal cancer cell-genomics consortium (VA4C) after participating in a successful field-based meeting in Chicago in May 2017 (funded by VA ORD). Specifically, this proposal will be part of a cluster of merit review projects that are aimed at advancing our understanding of CRC pathogenesis and treatment response with a focus on the roles of the microbiome and CRC stem cells. The importance of the intestinal microbiome to the development and progression of CRC is supported by a range of evidence including epidemiological links between diet and CRC risk, reproducible associations of specific microbes such as Fusobacterium with human CRC, mouse models indicating augmentation of CRC formation and metastasis by microbiota, and mouse models showing that the microbiome modulates chemotherapy response. We hypothesize that: 1) The intestinal microbiome, through direct invasion of tumor tissue and release of bioactive microbial products, is associated with specific CRC clinical/histologic phenotypes and molecular subclasses defined by transcriptional profiles. 2) The intestinal microbiome influences the risk of recurrence after surgery and chemotherapy by modulating anti-tumor immunity and the metabolism of chemotherapeutics. 3) The treatment of locally advanced CRC with surgical resection and chemotherapy alters the intestinal microbiome, which may influence the likelihood of future recurrences. To study these hypotheses, in Aim 1 we will utilize the multi-center clinical infrastructure of this CMA to collect fecal and tumor samples from 400 male and female Veterans with stage I-III CRC for analysis of the microbiome, metabolome, and transcriptome. Intestinal microbes and metabolites will be identified that are associated with tumor phenotype and molecular signature, as defined by gene transcripts, functional pathways and non-coding RNAs. In Aim 2, we will perform longitudinal follow-up of 200 Veterans with stage II- III colorectal cancer to elucidate baseline microbes and metabolites that predict subsequent risk for recurrence. In addition, we will obtain fecal samples before, during and after surgery then chemotherapy, and annually thereafter to identify microbial shifts with treatment and their association with future recurrence. In Aim 3, we will link compositional and functional shifts in the intestinal microbiome to CRC by using the C57BL/6 ApcMin strain of mice that is highly susceptible to spontaneous intestinal adenoma formation. We will examine the effect of colonization with human microbiota obtained from patients with high or low immune infiltration and immune transcriptional state, to assess adenoma/CRC formation and the intratumor immune response. We will also study the response to chemotherapy in mice engrafted with CRC cells and colonized with the stool of patients that had a recurrence, or a sustained remission, to evaluate microbiome-mediated differences in therapeutic response.