Design and characterization of bacterial population dynamics in solid tumor models

实体瘤模型中细菌种群动态的设计和表征

• 批准号: 10456087
• 负责人: JEFF M HASTY
• 金额: $ 62.84万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN DIEGO
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-08-01 至 2025-04-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10456087
• 关键词: Affect; Ally; Anaerobic Bacteria; Animal Model; Bacteria; Bacterial Genes; Behavior; Biological Models; Biosensing Techniques; Biosensor; CCL21 gene; CRISPR/Cas technology; Cancer Model; Colonoscopy; Colorectal; Colorectal Cancer; Colorectal Neoplasms; Complex; Cues; Cytolysis; Data; Development; Disease; Drug Delivery Systems; Engineered Probiotics; Engineering; Environment; Escherichia coli; Future; Gases; Gel; Gene Cluster; Gene Expression; Genes; Genetic; Genome; Glucose; Goals; Growth; Growth Factor; Harvest; Health; High Fat Diet; Histology; Human; Human body; Hypoxia; Image; Imaging technology; Immunologic Surveillance; In Situ Hybridization; In Vitro; Intercellular Fluid; Intestines; Lead; Liquid substance; Liver; Luciferases; Maintenance; Malignant Neoplasms; Malignant neoplasm of gallbladder; Malignant neoplasm of liver; Malignant neoplasm of lung; Malignant neoplasm of ovary; Malignant neoplasm of pancreas; Measures; Methods; Microbe; Microfluidic Microchips; Microscopy; Modeling; Molecular; Monitor; Mucous Membrane; Mus; Nutrient; Optical reporter; Oral; Organoids; Pathologic; Penetration; Play; Population; Population Dynamics; Primary carcinoma of the liver cells; Probiotics; Property; Reporting; Research; Resolution; Role; Safety; Solid Neoplasm; Specificity; Structure; System; Techniques; Technology; Testing; Time; Tissues; Ultrasonography; Vesicle; base; clinically relevant; design; design and construction; drug production; effectiveness study; environmental change; genome wide screen; genome-wide; high resolution imaging; human disease; improved; in vivo; in vivo Model; liver cancer model; luminescence; malignant breast neoplasm; malignant mouth neoplasm; microbial; microfluidic technology; mouse model; neoplastic; nonalcoholic steatohepatitis; novel; pre-clinical; preference; promoter; quorum sensing; response; screening; synthetic biology; tool; tumor; tumor growth; tumor microenvironment; ultrasound

Project Summary It is increasingly clear that bacteria play an important role in human health. While it is natural to focus on how intestinal bacteria affect disease, intriguing findings have elucidated the extent to which bacteria inhabit solid tumors. Microbes have been detected in lung, pancreatic, breast, oral, gallbladder, ovarian, liver, and colorectal cancers. Localization has been ascribed to several mechanisms, including preference for anaerobic or facultative anaerobic bacteria to grow in the hypoxic core of tumors, presence of bacterial nutrients, lack of immune surveil- lance, and leakiness of the often poorly structured vasculature surrounding neoplastic tissue. This tendency for localization to solid tumors suggests that bacteria could be engineered for precise and robust drug production and delivery from within the solid tumor environment. This dovetails with 20 years of progress in synthetic biology, which has tended to focus on microbial engineering. However, information on how the tumor microenvironment affects bacterial growth is largely unknown. The microenvironment will affect bacterial gene expression that ul- timately underlies the functionality of engineered therapies, and it is difficult to imagine a predictive framework for engineered bacterial therapies without a quantitative understanding of how bacteria react to the environment of a growing tumor. We will use a probiotic strain of E. coli with an established safety record to develop a novel class of biosensors to noninvasively investigate bacterial growth in the tumor microenvironment. Initially, we will develop lysis-based biosensors that respond to specific tumor environment targets: hypoxia, pH, glucose, and lactate (Aim 1). We will also engineer an inducible quorum sensing (QS) system that enables external control of bacterial population dynamics, including the ability to eliminate a specific strain whenever desired (Aim 1). Together these strains will allow us to modulate and monitor population dynamics in vivo, enabling both sens- ing of the local environment and maintenance of an external control switch. We will test these strains using an established in vitro organoid model (Aim 2) and in two clinically relevant animal models for solid tumor growth. Additionally, we will use our previously developed dynOMICS technology to screen tumor extract from the two animal models and construct a second suite of biosensors for monitoring the tumor environment (Aim 2). These biosensors will then be tested in the animal models. We will visualize bacterial populations in a colorectal tumor model with bacteria that are engineered to produce luciferase in order to monitor colony dynamics using our es- tablished methods (Aim 3). We will also build on recently reported technology whereby bacteria are modified for use with ultrasound through addition of gas vesicles that permit high resolution imaging of the engineered bac- teria. We will use the ultrasound method to investigate NASH-induced hepatocellular carcinoma (HCC) where a high-fat diet is used to induce HCC at 20 weeks in mice (Aim 4). This project will quantitatively characterize how bacterial strains sense, respond, and grow in the tumors. The results will establish a platform for future exploration of therapies that are produced and delivered by bacteria that grow within solid tumors.

项目摘要 越来越清楚的是，细菌在人类健康中发挥着重要作用。虽然关注如何 肠道细菌影响疾病，有趣的发现已经阐明了细菌在固体中的栖息程度 肿瘤的在肺、胰腺、乳腺、口腔、胆囊、卵巢、肝脏和结直肠中检测到微生物 癌的定位已被归因于几种机制，包括偏好厌氧或兼性 厌氧细菌在肿瘤的缺氧核心中生长，细菌营养物的存在，缺乏免疫监视， 以及肿瘤组织周围通常结构不良的脉管系统的渗漏。这种倾向， 定位于实体瘤表明细菌可以被工程化用于精确和稳健的药物生产， 从实体瘤环境内递送。这与合成生物学20年来的进展相吻合， 它倾向于关注微生物工程。然而，关于肿瘤微环境如何 影响细菌生长的因素在很大程度上是未知的。微环境会影响细菌基因的表达， 它是工程治疗功能的基础，很难想象一个预测框架。 在没有定量了解细菌如何对环境作出反应的情况下， 一个正在生长的肿瘤。我们将使用E.大肠杆菌与建立安全记录，以开发一种新的 这类生物传感器用于非侵入性地研究肿瘤微环境中的细菌生长。最初我们 将开发基于裂解的生物传感器，对特定的肿瘤环境目标做出反应：缺氧，pH值，葡萄糖， 和乳酸（目标1）。我们还将设计一个诱导性群体感应（QS）系统，使外部控制 细菌种群动态，包括在需要时消除特定菌株的能力（目标1）。 这些菌株将使我们能够调节和监测体内的种群动态，使两种意义上的 本地环境的维护和外部控制开关的维护。我们将使用 建立体外类器官模型（Aim 2）和两种临床相关的实体瘤生长动物模型。 此外，我们将使用我们以前开发的dynOMICS技术来筛选两种肿瘤提取物， 动物模型，并构建第二套生物传感器用于监测肿瘤环境（目标2）。这些 然后将在动物模型中测试生物传感器。我们将观察结直肠肿瘤中的细菌种群 模型与细菌，工程生产荧光素酶，以监测菌落动态使用我们的es- 方法（目标3）。我们还将建立在最近报道的技术基础上， 通过加入允许工程化BAC的高分辨率成像的气泡与超声一起使用， teria。我们将使用超声方法研究NASH诱导的肝细胞癌（HCC）， 使用高脂肪饮食在小鼠中诱导20周的HCC（目的4）。该项目将定量描述 细菌菌株是如何感知、反应和在肿瘤中生长的。研究结果将为未来的 探索由实体瘤内生长的细菌产生和提供的疗法。