Modeling bi-directional signaling and cytoskeletal dynamics in 3D cell migrations

描述（由申请人提供）：健康和患病系统中的细胞结构和功能受细胞与底层和周围三维细胞外基质相互作用的调节。众所周知，这些复杂的生物化学和生物力学相互作用独立地调节肿瘤进展、侵袭和转移。例如，在转移性乳腺癌中，细胞对生物化学和生物物理刺激的异常反应通常由细胞骨架机制的参与引发。因此，肌动蛋白相互作用蛋白被发现在生化和粘附促进线索之间的信号网络串扰的联系。一个这样的例子是Mena，肌动蛋白调节蛋白的Ena/VASP家族的成员，其特征在于在侵袭和转移期间的异常细胞信号传导应答。然而，改变的信号网络如何转化为机械过程，以及这些亚细胞机械过程如何在3D环境中转化为全细胞迁移仍然很难理解。在这里，基于我们的初步数据，我们假设在3D环境中增加的肿瘤细胞侵袭性是由将异常分子水平的信号传导事件与分子、大分子和细胞生物力学过程相结合来控制的。 我们在这项提案中的主要目标是通过弥合分子水平上的体外信号研究与3D中的分子力学和细胞模型之间的知识差距来严格测试我们的假设，并通过3D环境中的定量实验来测试我们模型的预测。我们计划开发和验证我们的细胞模型，使用以下三个具体目标：目标一：开发一个整合的亚细胞模型的细胞骨架粘弹性和细胞内信号 在原生的3D矩阵中。目的II：在3D矩阵中开发细胞迁移的定量模型， 利用来自Aim I的亚细胞模型的结果。目标三：目的I和II B的结果，量化了信号传导如何与细胞力学机制和细胞外基质特性协同作用以调节3D中的细胞迁移。所有这三个目标都建立在计算和实验研究的强有力的初步数据基础上，并将为机械和生物化学途径之间的耦合以及从亚细胞结构到细胞水平的信息整合提供基本见解。与此同时，对3D环境的关注将创造有关原生环境中细胞系统的新的生理相关知识。最后，通过这项工作开发的新平台将能够测试临床相关的假设，并有助于定量了解癌症进展各个阶段的复杂多尺度过程。

DESCRIPTION (provided by applicant): Cellular structure and function, in healthy and diseased systems, is regulated by the interaction of cells with the underlying and surrounding three-dimensional extra-cellular matrix. These complex biochemical and biomechanical interactions, independently, are well known to regulate tumor progression, invasion and metastasis. For example, the aberrant response of cells to biochemical and biophysical stimuli in metastatic breast cancer is often initiated by engagement of the cytoskeletal machinery. As such, actin interacting proteins are found at the nexus of signaling network crosstalk between biochemical and adhesion-promoting cues. One such example is Mena, a member of the Ena/VASP family of actin regulatory proteins, which has been characterized for aberrant cell-signaling response during invasion and metastasis. However, how the altered signaling network is translated into the mechanical processes, and how are these sub-cellular mechanical processes then converted into whole cell migration in 3D environments remain largely elusive. Here, based on our preliminary data, we hypothesize that increased tumor cell invasiveness in 3D environments, is governed by coupling aberrant molecular level signaling events to molecular, macromolecular and cellular biomechanical processes. Our primary goal in this proposal is to rigorously test our hypothesis by bridging the knowledge gap between in vitro signaling studies at the molecular level, and molecular mechanical and cellular models in 3D, and test the predictions of our models through quantitative experiments in 3D environments. We plan to develop and validate our cellular models using the following three specific aims: Aim I: Develop an integrated subcellular model of cytoskeletal viscoelasticity and intracellular signaling in native like 3D matrices. Aim II: Develop a quantitative model of cell migration, in 3D matrices, utilizing results from the subcellular model of Aim I. Aim III: Validate results of Aims I and II b quantifying how signaling acts cooperatively with cellular mechanics machinery and extracellular matrix properties to regulate cell migration in 3D. All three aims build upon strong preliminary data in both computation and experimental studies and will provide both fundamental insights into the coupling between mechanical and biochemical pathways and integration of information from sub-cellular structures to the cellular level. At the same time, the focus on 3D environments will create new and physiologically relevant knowledge about cellular systems in native like environments. Finally, novel platforms developed through this work will be able to test clinically relevant hypotheses and help in quantitatively understanding complex multi-scale processes during various stages of cancer progression.