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

基本信息

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
项目类别：
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

项目摘要

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.

项目概要越来越明显的是，细菌在人类健康中发挥着重要作用，而人们自然会关注细菌如何发挥重要作用。肠道细菌影响疾病，有趣的研究阐明了细菌在固体中栖息的程度已在肺、胰腺、乳腺、口腔、胆囊、卵巢、肝脏和结直肠中检测到微生物。癌症的定位归因于多种机制，包括对厌氧或兼性的偏好。厌氧细菌在肿瘤缺氧的核心生长，存在细菌营养物质，缺乏免疫监视以及肿瘤组织周围结构不良的脉管系统的渗漏。实体瘤的定位表明细菌可以被设计用于精确和稳健的药物生产这与合成生物学 20 年来的进展相吻合，然而，它倾向于关注微生物工程如何影响肿瘤微环境。影响细菌生长的因素在很大程度上是未知的。微环境会影响细菌的基因表达。工程疗法的功能密切相关，很难想象一个预测框架用于工程细菌疗法，无需定量了解细菌对环境的反应我们将使用具有既定安全记录的大肠杆菌益生菌菌株来开发一种新型药物。最初，我们使用一类生物传感器来非侵入性地研究肿瘤微环境中的细菌生长。将开发基于裂解的生物传感器，可响应特定的肿瘤环境目标：缺氧、pH、葡萄糖、我们还将设计一个可诱导群体感应 (QS) 系统，以实现外部控制。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群体动态，从而使两种感觉我们将使用一个本地环境和外部控制开关的维护来测试这些菌株。建立了体外类器官模型（目标 2）和两个临床相关的实体瘤生长动物模型。此外，我们将使用我们之前开发的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来监测肿瘤环境（目标 2）。然后，我们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群。使用经过工程改造产生荧光素酶的细菌模型，以便使用我们的 es- 监测菌落动态我们还将以最近报道的技术为基础，对细菌进行修饰。通过添加气体囊泡与超声波一起使用，允许对工程化的 bac- 进行高分辨率成像我们将使用超声方法来研究 NASH 诱发的肝细胞癌 (HCC)。使用高脂肪饮食在 20 周时诱导小鼠发生 HCC（目标 4）。细菌如何感知菌株、做出反应并在肿瘤中生长，这些结果将为未来建立一个平台。探索由实体瘤内生长的细菌产生和传递的疗法。