The Role of FAK-related-non-kinase (FRNK) in Lung Fibrosis

描述（由申请人提供）：特发性肺纤维化（IFF）的特征是成纤维细胞/肌成纤维细胞灶和过度的细胞外基质（ECM）蛋白积累，其中成纤维细胞迁移到损伤区域起关键作用。Focal Adhesion Kinase （FAK）介导整合素和生长因子启动的细胞迁移。过度表达FAK的c端同源蛋白，FAK相关的非激酶（FRNK），抑制间充质细胞中生长因子和整合素受体促进的依赖FAK的细胞迁移。然而，FRNK在肺成纤维细胞迁移中的作用及其在包括肺纤维化在内的体内组织损伤/修复过程中的作用仍未明确。我们假设FRNK通过抑制fak依赖性成纤维细胞迁移来调节体内肺纤维化。为了验证这一假设，提出了三个具体目标。在Specific Aim 1中，我们将确定FRNK在抑制fak介导的肺成纤维细胞迁移和迁移信号传导中的作用。成纤维细胞迁移将在获得/失去FRNK功能的方法中进行测试，使用来自肺纤维化患者和非纤维化对照组的患者来源的原代人肺成纤维细胞。在特异性目标2中，我们将确定FRNK在体内肺纤维化中的作用。将在frnk基因敲除小鼠和基因野生型小鼠中评估对促纤维化剂博来霉素的损伤/修复反应。此外，从这些小鼠分离的原代肺成纤维细胞的细胞迁移和迁移信号将被确定。FRNK在骨髓来源的细胞和纤维细胞、上皮-间充质转化和肌成纤维细胞分化中的募集作用及其由此产生的纤维化作用将被确定。在Specific Aim 3中，我们将确定FRNK表达与博莱霉素诱导的肺纤维化纤维增生性病变的时空关系，并表征FRNK在肺成纤维细胞中表达的体内介质。这些数据将支持或反驳我们的假设，即FRNK调节肺损伤和修复过程中成纤维细胞的迁移，从而影响体内纤维化过程。这些研究将支持我的实验室的长期目标，即利用从这些研究中获得的知识来开发针对人类特发性肺纤维化的新型治疗方法。

DESCRIPTION (provided by applicant): Idiopathic pulmonary fibrosis (IFF) is characterized by fibroblast/myofibroblastic foci and excessive extracellular matrix (ECM) protein accumulation, in which fibroblast migration into the injured areas plays a critical role. Focal Adhesion Kinase (FAK) mediates integrin- and growth factor-initiated cell migration. Overexpression of FAK's C-terminal homologous protein, FAK-related-non-kinase (FRNK), inhibits FAKdependent cell migration promoted by growth factors and integrin receptors in mesenchymal cells. However, the role of FRNK in lung fibroblast migration and its role in tissue injury/repair processes in vivo including lung fibrosis remain undefined. We hypothesize that FRNK modulates lung fibrosis in vivo through inhibition of FAK-dependent fibroblast cell migration. To test this hypothesis, three specific aims are proposed. In Specific Aim 1, we will determine the role of FRNK in inhibiting FAK-mediated lung fibroblast cell migration and migration signaling. Fibroblast migration will be tested in gain/loss of FRNK function approaches using patient-derived primary human lung fibroblast cells from pulmonary fibrotic patients and non-fibrotic controls. In Specific Aim 2, we will determine the role of FRNK in lung fibrosis in vivo. The injury/repair response to the pro-fibrotic agent, Bleomycin, will be assessed in FRNK-knockout mice and congenic wild type mice. Furthermore, cell migration and migration signaling of primary lung fibroblasts isolated from these mice will be determined. The role of FRNK in the recruitment, and its resultant fibrotic effects, on bone-marrow derived cells and fibrocytes, and on epitheilal-mesenchymal transition, and on myofibroblast differentiation will be determined. In Specific Aim 3, we will determine the spatial-temporal relationship of FRNK expression with fibroproliferative lesions in Bleomycin-induced lung fibrosis, and characterize the in vivo mediators of FRNK expression in lung fibroblasts. These data will either support or refute our hypothesis that FRNK modulates fibroblast migration during lung injury and repair, and thereby affects the fibrotic processes in vivo. These studies will support the long-term goal of my laboratory to utilize knowledge gained from these studies to develop novel therapeutic approaches targeted to idiopathic pulmonary fibrosis in humans.