Mechanisms of adhesion and invasion in hyaluronic acid matrices

项目摘要/摘要 透明质酸(HA)是人脑中含量最丰富的成分，在那里它提供基本的结构， 机械和细胞教育功能。透明质酸与其受体CD44之间的黏附对调节 发育和动态平衡，以及HA和/或CD44的失调导致了许多脑部疾病， 包括侵袭致命性脑肿瘤的胶质母细胞瘤(GBM)。尽管有明确的生物学意义， HA-CD44黏附，对HA-CD44黏附的生物物理机制知之甚少。 CD44相互作用推动细胞黏附、迁移或基质重塑或HA如何组成(例如，分子 重量)会影响黏附和迁移。在过去的十年里，我们的团队做出了开创性的贡献 解决这些问题，包括引入和提炼合成3D HA矩阵作为 研究基底膜的侵袭。我们还发现，CD44转导基于HA的机械信号来调节 细胞形状、细胞骨架组装和运动性。最近，我们发现GBM细胞通过使用 “微触角”(McTns)是一种依赖CD44的过程，从细胞体延伸出几十微米，是 与HA消化相关，并通过包括以下的复合体机械连接到细胞骨架 IQGAP1和CLIP170。McTns与在侵袭性疾病中观察到的结构具有重要的相似之处 在活体中，McTN组分的过度表达预示着侵袭性进展和不良进展 在GBM中存活。在此R01应用程序中，我们将利用这些发现和生物材料平台来 促进该领域对HA和CD44如何促进细胞黏附、迁移和侵袭的理解。在……里面 我们的第一个目标，我们将研究McTns如何促进黏附、侵袭和基质重塑。在我们的 第二个目标，我们将确定脑组织中HA网络的生物物理特征如何对3D做出贡献 迁移，使用GBM作为模型系统。我们的方法的特点是紧密集成了工程化 生物材料培养模型，以人GBM干细胞/启动细胞为特征的小鼠模型，以及活检分析 取自人类基底膜的特定解剖区域。我们的多机构团队还独特地结合了 在生物材料、机械生物学、神经外科和癌症生物学方面的专业知识。成功完成这些任务 研究将对HA和CD44参与的生物物理基础产生前所未有的见解 粘连和侵袭，这是一个高度关注的问题，可能导致新的治疗靶点 GBM。

PROJECT SUMMARY/ABSTRACT Hyaluronic acid (HA) is the most abundant component of the human brain, where it serves essential structural, mechanical, and cell-instructive functions. Adhesion between HA and its receptor CD44 critically regulates development and homeostasis, and dysregulation of HA and/or CD44 causally drives many brain pathologies, including invasion of the deadly brain tumor glioblastoma (GBM). Despite the clear biological significance of HA-CD44 adhesion, comparatively little is known about either the biophysical mechanisms through which HA- CD44 interactions drive cell adhesion, migration, or matrix remodeling or how HA composition (e.g. molecular weight) influences adhesion and migration. Over the past decade, our team has made seminal contributions to addressing these questions, including introducing and refining synthetic 3D HA matrices as a culture model for studying GBM invasion. We also discovered that CD44 transduces HA-based mechanical signals to regulate cell shape, cytoskeletal assembly, and motility. Most recently, we discovered that GBM cells engage HA using “microtentacles” (McTNs), CD44-dependenent processes that extend tens of microns from the cell body, are associated with HA digestion, and mechanically couple to the cytoskeleton through a complex that includes IQGAP1 and CLIP170. McTNs bear important similarities to structures that have been observed in invasive GBMs in vivo, and overexpression of McTN components is predictive of with aggressive progression and poor survival in GBM. In this R01 application, we will leverage these discoveries and biomaterial platforms to advance the field’s understanding of how HA and CD44 contribute to cell adhesion, migration, and invasion. In our first aim, we will investigate how McTNs facilitate adhesion, invasion, and matrix remodeling. In our second aim, we will determine how biophysical features of the HA network in brain tissue contributes to 3D migration, using GBM as a model system. Our approach is distinguished by tight integration of engineered biomaterial culture models, mouse models featuring human GBM stem/initiating cells, and analysis of biopsies obtained from specific anatomic regions of human GBMs. Our multi-institutional team also uniquely combines expertise in biomaterials, mechanobiology, neurosurgery, and cancer biology. Successful completion of these studies will yield unprecedented insight into the biophysical basis through which HA and CD44 contribute to adhesion and invasion, a problem of high fundamental interest that may lead to novel therapeutic targets in GBM.