Microfluidic tumor models to analyze the role of physicochemical cues in the angi

描述（由申请人提供）：血管生成开关在肿瘤血管形成和转移中起着重要作用;然而，微环境条件调节这一过程的潜在细胞和分子机制仍不清楚。该项目将解决这样的假设，即不同的肿瘤样小生境的产生和位于这些小生境内的细胞之间的串扰上调了关键肿瘤细胞因子的表达，这些细胞因子有助于招募骨髓来源的内皮祖细胞（EPCs）和增强肿瘤血管生成。为了解决我们的假设，我们将利用基于物理科学的癌症生物学方法，该方法结合了3D细胞培养，微流体和数学建模。我们的研究设计基于4个目标：在目标1中，我们将设计3-D微流体肿瘤培养物，这将使我们能够测试以下假设：可溶性因子的信号传导（由氧张力的空间分辨差异调节）提供了一种旁分泌机制，该机制跨越小生境以调节肿瘤细胞和基质细胞的细胞因子差异表达。在目标2中，我们将评估目标1中阐明的肿瘤和基质细胞信号传导的整体和局部动力学是否影响侵袭性血管生成。为此，我们将扩展目标1中开发的微流控平台，以整合内皮化微通道。该系统将是可重塑的，并且可以进行调整以表现出增强的基质硬度，这是肿瘤基质的典型特征。在目标3中，我们将确定目标2中定义的物理化学介导的新血管形成变化是否导致血管龛的形成，这些血管龛影响EPCs的表型身份、空间和时间贡献、生物学功能及其在肿瘤血管生成中的作用。最后，在目标4中，我们将对已经并入微流体微容器中的EPC进行动态全局转录组和表观基因组分析。生成的数据将被纳入计算信号转导网络分析，以确定可能负责物理化学介导的血管生成开关变化的分子靶点。我们提出的研究有可能通过提高我们对肿瘤血管生成开关的理解和确定可能参与这一过程的分子机制来改善目前的抗血管生成治疗策略，并提供治疗相关的靶点。 公共卫生相关性：肿瘤血管生成是肿瘤的一个关键事件，涉及骨髓来源的内皮祖细胞的募集;然而，微环境条件调节这些过程的确切机制和作用尚不清楚。使用显微病理学3-D肿瘤模型和数学建模方法，本研究将解决的假设，即氧依赖性肿瘤龛的创建，这些龛之间的旁分泌细胞串扰，上调表达的关键肿瘤细胞因子，影响侵袭血管生成和招募内皮祖细胞。这种跨学科的策略有可能彻底改变我们对肿瘤血管形成的理解，并从根本上阐明癌症中促血管生成活性的新机制，从而为改善抗血管生成治疗和临床结局奠定基础。

DESCRIPTION (provided by applicant): The angiogenic switch plays a fundamental role in tumor vascularization and metastasis; however, the underlying cellular and molecular mechanisms by which microenvironmental conditions regulate this process are still unclear. This project will address the hypothesis that the creation of distinct tumor-like niches and crosstalk between cells residing within these niches up-regulates expression of pivotal tumor cytokines that contribute to the recruitment of bone marrow-derived endothelial progenitor cells (EPCs) and enhanced tumor angiogenesis. To address our hypothesis we will utilize a physical-sciences based cancer biology approach that combines 3-D cell culture, microfluidics, and mathematical modeling. Our study design is based on 4 aims: In aim 1, we will design 3-D microfluidic tumor cultures that will allow us to test the hypothesis that the signaling of soluble factors, as regulated by spatially resolved differences in oxygen tension, provides a paracrine mechanism that spans between niches to regulate the differential expression of cytokines by both tumor and stromal cells. In aim 2, we will evaluate whether the global and local dynamics of tumor and stromal cell signaling, as elucidated in aim 1, impact invasion angiogenesis. To this end, we will expand the microfluidic platform developed in aim 1 to integrate endothelialized microchannels. This system will be remodelable and can be adjusted to exhibit enhanced matrix stiffness as typical of the tumor stroma. In aim 3, we will determine whether physicochemically mediated changes in neovessel formation as defined in aim 2 lead to the formation of vascular niches that impact the phenotypic identity, spatial and temporal contribution, and biological function of EPCs and their role in tumor angiogenesis. Finally, in aim 4, we will conduct dynamic global transcriptome and epigenome analysis of EPCs that have incorporated in the microfluidic microvessels. The generated data will be incorporated into computational signal transduction network analysis to identify molecular targets that may be responsible for physicochemically mediated changes in the angiogenic switch. Our proposed studies have the potential to improve current strategies of anti-angiogenic therapies by enhancing our understanding of the tumor angiogenic switch and identifying molecular mechanisms that may be involved in this process and provide therapeutically relevant targets. PUBLIC HEALTH RELEVANCE: Tumor angiogenesis represents a critical event of cancer that involves the recruitment of bone marrow derived endothelial progenitor cells; however, the exact mechanisms and effects by which microenvironmental conditions regulate these processes are not well understood. Using micropathological 3-D tumor models and mathematical modeling approaches this research will address the hypothesis that the creation of oxygen dependent tumor niches, and paracrine cellular crosstalk between these niches, up-regulates expression of pivotal tumor cytokines that impact invasion angiogenesis and the recruitment of endothelial progenitor cells. This interdisciplinary strategy has the potential to revolutionize our understanding of tumor vascularization and elucidate fundamentally new mechanisms of pro-angiogenic activity in cancers that could form a basis for improved anti-angiogenic therapies and clinical outcomes.