Regulation of Epidermal Differentiation on Engineered Polymer Substrates

描述(由申请人提供)：整合素介导的黏附在许多细胞过程中发挥核心作用，包括增殖、迁移和分化。在皮肤的表皮中，整合素受体已知影响干细胞分化；然而，来自ECM的信号与其他信号通路协调以决定细胞命运的机制尚不清楚。本研究的总体目标是研究整合素介导的黏附和β-连环蛋白相关信号通路在调节表皮分化中的相互作用。拟议的研究将使用工程聚合物底物来控制呈现给细胞的细胞黏附配体的类型、密度和空间组织。这些明确的细胞-基质相互作用对表皮分化的影响将使用从野生型小鼠和表达可诱导的β-连环素、Notch和c-Myc的转基因小鼠分离的角质形成细胞来检验。这项工作的中心假设是整合素介导的与细胞外基质的黏附调节角质形成细胞的分化，这些反应受到β-连环蛋白信号和其他相关途径的调节。这项研究将在三个具体目标下进行：目标1：开发具有可控密度和模式的细胞黏附配体的聚(OEGMA)底物，以调节角质形成细胞的黏附和形态。目的：检测整合素介导的工程化基质黏附对角质形成细胞增殖和体外分化的影响。目的：探讨整合素介导的黏附和β-连环素相关途径在调节表皮分化中的相互作用。这项研究方案的成功完成将为研究参与调节表皮分化的多个途径的相互作用提供重要的见解。长期目标是建立新的实验系统，以提高对干细胞谱系选择、分化和自我更新的基本理解。这项研究在癌细胞生物学领域具有重要意义。由于整合素和β-连环素信号也影响肿瘤的发展和侵袭，深入了解表皮干细胞的行为将促进目前对皮肤癌病理的理解，并有助于治疗药物的开发。

DESCRIPTION (provided by applicant): Integrin-mediated adhesion plays a central role in numerous cellular processes including proliferation, migration, and differentiation. Within the epidermis of the skin, integrin receptors are known to influence stem cell differentiation; however, the mechanism by which cues from the ECM coordinate with other signaling pathways to determine cell fate remains unclear. The overall goal of this research proposal is to investigate the interaction between integrin-mediated adhesion and beta-catenin related signaling pathways in the regulation of epidermal differentiation. The proposed studies will employ engineered polymer substrates to control the type, density, and spatial organization of cell-adhesive ligands presented to the cells. The influences of these defined cell-matrix interactions on epidermal differentiation will be examined using keratinocytes isolated from wild type mice and transgenic mice with inducible beta-catenin, Notch, and c-Myc expression. The central hypothesis for this work is that integrin-mediated adhesion to the extracellular matrix regulates keratinocyte differentiation and that these responses are modulated by the strength of beta-catenin signaling and other related pathways. This research will be carried out in three specific aims: Aim 1: Develop poly-(OEGMA) substrates presenting controlled densities and patterns of cell adhesive ligands to modulate keratinocyte adhesion and morphology. Aim 2: Examine the effects of integrin-mediated adhesion to engineered substrates on keratinocyte proliferation and in vitro differentiation. Aim 3: Investigate the interactions between integrin-mediated adhesion and beta-catenin related pathways in the regulation epidermal differentiation. The successful completion of this research proposal will provide significant insights into the interacting roles of multiple pathways involved in the regulation of epidermal differentiation. The long term objective is to establish novel experimental systems that will improve the fundamental understanding of stem cell lineage selection, differentiation, and self renewal. This research has important implications in the field of cancer cell biology. Since integrin and beta-catenin signaling also influence tumor development and invasion, insights into the behavior of epidermal stem cells will advance the current understanding of skin cancer pathology and aid in the development of therapeutic agents.