Development of novel metastatic mouse models that recapitulate the major immune contexts of human colon cancer

开发新的转移性小鼠模型来概括人类结肠癌的主要免疫环境

基本信息

批准号：
10304921
负责人：
TYLER E. JACKS
金额：
$ 32.21万
依托单位：
MASSACHUSETTS INSTITUTE OF TECHNOLOGY
依托单位国家：
美国
项目类别：
财政年份：
2019
资助国家：
美国
起止时间：
2019-12-01 至 2022-11-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10304921
关键词：
Address Adoptive Transfer Alleles Antibodies Antigens Benchmarking CRISPR/Cas technology Cancer Model Chickens Clinical Clinical Trials Colon Colon Carcinoma Colonoscopy Colorectal Cancer Comparative Study DNA Development Disease Dissection Engineering Enterobacteria phage P1 Cre recombinase FDA approved Genes Genetic Genetic Engineering Goals Guide RNA Histology Human Immune Immune Evasion Immune checkpoint inhibitor Immune response Immunotherapy Injections Kinetics Knock-out Lentivirus Liver Lung MSH2 gene Mediating Methodology Methods Mismatch Repair Mismatch Repair Deficiency Modeling Mus Mutation Neoplasm Metastasis Organoids Ovalbumin Patients Preclinical Testing Predisposition Primary Neoplasm Refractory Research Solid Neoplasm Somatic Mutation Standardization Stimulus T cell response T cell therapy T-Lymphocyte Techniques Testing Tissues Translational Research Treatment outcome Tumor Antigens Tumor-infiltrating immune cells analog anti-CTLA4 antibodies anti-PD-1 antigen-specific T cells base cancer therapy cancer type chemotherapy clinical predictors colon cancer patients design exhaustion immune checkpoint immune checkpoint blockade immunogenic immunogenic cell death immunogenicity immunotherapy trials improved inducible gene expression innovation model development mouse genetics mouse model mutant neoantigens next generation sequencing novel organoid transplantation patient population patient subsets pre-clinical preclinical trial programmed cell death protein 1 response transplant model tumor tumor-immune system interactions

项目摘要

The purpose of this proposal is to develop novel mouse models of colorectal cancer (CRC) with appropriate immune responses. These models have been designed to address limitations present in current models of CRC in order to enhance their suitability for translational research in immunotherapy. Immune checkpoint inhibitors have revolutionized treatment of solid tumors, and brought to light the critical importance of tumor immune context in treatment outcome. CRC with DNA mismatch repair (MMR) deficiency is characterized by a high burden of somatic mutations, increased T cell infiltration, and a favorable response to checkpoint blockade. Unfortunately, the majority of CRC has a lower mutational burden and is refractory to these treatments. Preclinical mouse models are powerful platforms for investigating the factors underlying response to immunotherapy. However, no single model faithfully recapitulates primary tumor development in the colon microenvironment, metastatic dissemination to the liver and lung, and the major immune contexts underlying variability in immunotherapy response in human CRC. To address these significant translational deficiencies, we will use an innovative technique employing colonoscopy-guided sub-mucosal injection of lentivirus or tumor organoids to induce focal autochthonous and orthotopic tumors in the colon that readily metastasize. In Aim 1, we will engineer a model that modulates tumor immunogenicity through inducible expression of a model antigen. We will dissect the features of the induced anti-tumor T cell response and investigate the utility of this model for testing adoptive T cell therapy by transferring antigen-specific T cells. To potentiate adoptive T cell therapy and mirror ongoing clinical trials in humans, we will assess the efficacy of CRISPR-Cas9-mediated deletion of immune checkpoints in T cells prior to transfer. In Aim 2, we will model immunotherapy-responsive CRC by targeting the essential DNA MMR genes Msh2 and Mlh1 and use next-generation sequencing to characterize the mutational landscapes of resulting MMR-deficient versus proficient tumors. In Aim 3, we will perform preclinical trials of immune checkpoint blockade in these models to explore their ability to recapitulate the responses of human CRC patient populations. We will also test a novel combination of immunogenic chemotherapy and checkpoint blockade, based on the hypothesis that immunogenic cell death may sensitize tumors with low mutational burden or minimal pre-existing T cell involvement to immune attack. This strategy is aimed at improving treatment for the majority of CRC patients, whose tumors are non-immunogenic and non- responsive to immunotherapy. The overarching goal of this research plan is to develop and benchmark a set of highly comparable CRC models that will be used to address why only a fraction of patients respond to immunotherapy. The proposed strategy is innovative in that it uses cutting-edge methods in mouse genetic engineering and cancer modeling to capture critical features of human CRC. This research will also include deep characterization of the immune microenvironment in these models and a comparison to humans.

该建议的目的是开发新型的结直肠癌的小鼠模型（CRC）免疫反应。这些模型旨在解决当前模型中存在的局限性 CRC为了增强其对免疫疗法转化研究的适用性。免疫检查点抑制剂已经彻底改变了对实体瘤的治疗，并揭示了肿瘤的重要性治疗结果中的免疫环境。 DNA不匹配修复（MMR）缺陷的CRC的特征是体细胞突变的高负担，T细胞浸润增加以及对检查点的有利反应封锁。不幸的是，大多数CRC具有较低的突变负担治疗。临床前鼠标模型是调查响应因素的强大平台进行免疫疗法。但是，没有单一模型忠实地概括了结肠中的原发性肿瘤的发展微环境，转移到肝脏和肺部以及主要的免疫背景人CRC免疫疗法反应的变异性。为了解决这些重大的翻译缺陷，我们将使用一种创新技术，采用结肠镜检查引导的慢跑病毒或肿瘤注射的亚粘膜下注射器官在结肠中诱导局灶性自围候和原位肿瘤，很容易转移。在AIM 1中，我们将设计一个模型，该模型通过模型的诱导表达调节肿瘤免疫原性抗原。我们将剖析诱导的抗肿瘤T细胞反应的特征，并研究此效用通过转移抗原特异性T细胞来测试过养T细胞疗法的模型。增强收养T细胞治疗和镜像正在进行的人类正在进行的临床试验，我们将评估CRISPR-CAS9介导的疗效在转移之前，T细胞中免疫检查点的删除。在AIM 2中，我们将建模免疫疗法响应性 CRC通过靶向必需的DNA MMR基因MSH2和MLH1并使用下一代测序表征由MMR缺陷与熟练肿瘤的突变景观。在AIM 3中，我们将在这些模型中对免疫检查点封锁进行临床前试验，以探索其概括的能力人类CRC患者人群的反应。我们还将测试免疫原性的新型组合化学疗法和检查点阻滞，基于免疫原性死亡可能敏感的假设突变负担低或最小的T细胞涉及免疫攻击的肿瘤。这个策略是旨在改善大多数CRC患者的治疗对免疫疗法的反应。该研究计划的总体目标是制定和基准一组高度可比的CRC模型将用于解决为什么只有一小部分患者反应的原因免疫疗法。提出的策略具有创新性，因为它在鼠标遗传中使用了尖端方法工程和癌症建模以捕获人类CRC的关键特征。这项研究还将包括在这些模型中对免疫微环境的深度表征以及与人类的比较。