Defining the role of type III collagen and the collagen-binding receptor DDR1 in metastatic dormancy

项目概要/摘要 背景：转移是癌症患者死亡的主要原因。播散性肿瘤细胞 (DTC) 治疗后数年或数十年，留下原发肿瘤并产生转移的种子靶器官。这个 生长延迟是由称为肿瘤休眠的过程介导的。细胞外基质（ECM）-肿瘤细胞 相互作用已被证明可以调节癌症的特征；从原发肿瘤生长到迁移， 侵袭和转移。然而，ECM 传感和重塑如何诱导和维持休眠 DTC 不清楚。此外，DTC 是否组装支持休眠的 ECM 利基来维持其 表型也是一个悬而未决的问题。我们将探讨 ECM 通过休眠进行重塑的假设 细胞通过构建富含 III 型胶原 (COL III) 的休眠 ECM 生态位来促进肿瘤休眠。 假设：我们的总体假设表明，休眠的癌细胞可以构建自己的“休眠- 通过重塑和沉积富含 COL III 的 ECM 来维持其表型，从而实现“支持性利基”。 目标：该项目的总体目标有两个：1）了解 COL III ECM 在 休眠支持生态位的形成以及 2) 确定与 III 型胶原 ECM 的相互作用 通过 DDR1 调节休眠到重新激活的转换。 具体目标：#1：确定纤维状胶原 III 网络如何有助于建立休眠支持网络 利基。 #2：确定胶原蛋白受体 DDR1 调节组装的分子机制 促静止 ECM。 研究设计/方法：1）可用于实时体内研究休眠细胞生物学的方法 是有限的。我们建议使用高分辨率成像工具结合休眠模型来研究肿瘤 休眠期间细胞-ECM 相互作用。我们一直在开发一种成像方法，包括：i) 多光子成像和二次谐波产生 (SHG) 以及 ii) 与休眠相关的活动报告器 测量休眠期间 p38/ERK 信号传导和细胞周期状态变化的特定途径。 2) 至 我们与 Naba 博士合作使用定量蛋白质组学来分析 ECM 组成和重塑。 相关性：该项目在概念和方法层面都是创新的。我们建议 研究转移的以下方面：1）DTC 如何创建富含 COL III 的休眠 ECM 生态位 维持休眠； 2）COL III/DDR1相互作用在调节休眠中的作用； 3) IFNg/STAT1信号传导如何 通过 ECM 重塑调节肿瘤休眠； 4) 如何破坏促静止 ECM 蛋白质组和 LTBP1 的增加介导休眠到重新激活的转变。我们希望我们的研究能够产生重大影响 对生物医学的影响，因为它们将揭示调节休眠细胞-ECM相互作用的机制， 这将是确定预防转移目标的有效方法。

Project Summary/Abstract Background: Metastasis is the primary cause of death of cancer patients. Disseminated tumor cells (DTCs) leave the primary tumor and seed target organs originating metastasis, years or decades after treatment. This delay in growth is mediated by a process called tumor dormancy. The extracellular matrix (ECM)-tumor cell interactions have been shown to regulate the hallmark of cancer; from primary tumor growth to migration, invasion and metastasis. However, how ECM sensing and remodeling can induce and sustain dormancy of DTCs is unclear. Moreover, whether DTCs assemble dormancy-supportive ECM niches to sustain their phenotype is also an unanswered question. We will explore the hypothesis that ECM remodeling by dormant cells contribute to tumor dormancy by constructing a dormant ECM niche rich in collagen III (COL III). Hypothesis: Our overall hypothesis states that dormant cancer cells can construct their own “dormancy- supportive niche” by remodeling and depositing a COL III rich ECM that sustain their phenotype. Objective: The overall goal of this project is two-fold: 1) to understand the role of the COL III ECM on the formation of dormancy-supportive niches and 2) to determine how the interaction with the collagen III ECM through DDR1 regulates the dormancy-to-reactivation transition. Specific Aims: #1: To determine how fibrillar collagen III networks contribute to establish a dormancy-supportive niche. #2: To identify the molecular mechanisms through which collagen receptor DDR1 modulates assembly of a pro-quiescence ECM. Study design/Methods: 1) The approaches available to study the biology of dormant cells in real-time in vivo are limited. We propose to use high-resolution imaging tools combined with dormancy models to study tumor cell-ECM interactions during dormancy. We have been developing an imaging approach that includes: i) Multiphoton imaging and second harmonic generation (SHG) and ii) activity reporters for dormancy-related specific pathways to measure changes in p38/ERK signaling and cell cycle status during dormancy. 2) To analyze the ECM composition and remodeling we use quantitative proteomics in collaboration with Dr. Naba. Relevance: This project is innovative both at the conceptual and at the methodological level. We propose to study the following aspects of metastasis: 1) how DTCs create a dormant ECM niche enriched in COL III to sustain dormancy; 2) the role of COL III/DDR1 interaction in regulating dormancy; 3) how IFNg/STAT1 signaling regulates tumor dormancy through ECM remodeling; 4) how disruption of a pro-quiescence ECM proteome and increase in LTBP1 mediate dormancy-to-reactivation transition. We expect our studies to have a significant impact on biomedicine because they will uncover the mechanisms regulating dormant cell-ECM interactions, which will be an efficient way of identifying targets to prevent metastasis.