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

描述(申请人提供)：血管生成开关在肿瘤血管形成和转移中起重要作用；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。这个项目将解决的假设是，不同的肿瘤样小生境的创建和驻留在这些小生境中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骨髓来源的内皮祖细胞(EPC)的招募和增强肿瘤血管生成。为了解决我们的假设，我们将利用一种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四个目标：在目标1中，我们将设计三维微流控肿瘤培养物，使我们能够检验这样一个假设，即受空间分辨的氧分压差异调节的可溶性因子的信号提供跨越生态位之间的旁分泌机制，以调节肿瘤和基质细胞的细胞因子的差异表达。在目标2中，我们将评估在目标1中阐明的肿瘤和基质细胞信号的全局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。该系统将是可改装的，可以调整以显示增强的基质硬度，这是肿瘤间质的典型特征。在目标3中，我们将确定目标2中定义的新血管形成的物理化学中介变化是否会导致血管生态位的形成，从而影响内皮祖细胞的表型特征、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，我们将对已整合到微流体微血管中的内皮祖细胞进行动态的全局转录组和表观基因组分析。生成的数据将被合并到计算信号转导网络分析中，以确定可能对血管生成开关的物理化学中介变化负责的分子靶点。我们提出的研究有可能通过加强我们对肿瘤血管生成开关的理解，识别可能参与这一过程的分子机制，并提供治疗相关的靶点，来改进当前的抗血管生成治疗策略。 公共卫生相关性：肿瘤血管生成是癌症的一个关键事件，涉及骨髓源性内皮祖细胞的招募；然而，微环境条件调节这些过程的确切机制和影响尚不清楚。利用微病理三维肿瘤模型和数学建模方法，本研究将解决这样的假设，即氧依赖肿瘤壁龛的创建以及这些壁龛之间的旁分泌细胞串扰，上调了关键肿瘤细胞因子的表达，影响侵袭血管生成和内皮祖细胞的招募。这种跨学科的策略有可能彻底改变我们对肿瘤血管生成的理解，并从根本上阐明癌症促血管生成活性的新机制，这可能形成改善抗血管生成治疗和临床结果的基础。

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.