PROJECT 3:CONNEXIN AND CADHERIN CROSSTALK IN PROSTATE CANCER PROGRESSION

项目 3：连接蛋白和钙粘蛋白在前列腺癌进展中的相互作用

• 批准号: 8360443
• 负责人: Parmender Paul Mehta
• 金额: $ 1.42万
• 依托单位: UNIVERSITY OF NEBRASKA MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-07-01 至 2012-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8360443
• 关键词: Cadherins; Cell-Cell Adhesion; Cells; Chimera organism; Connexin 43; Connexins; E-Cadherin; E-Cadherin Staining Method; Endocytosis; Epithelial Cells; Extracellular Domain; Funding; Gap Junctions; Grant; Growth; In Vitro; Malignant neoplasm of prostate; Mediating; Molecular; N-Cadherin; National Center for Research Resources; Nebraska; PC3 cell line; Pathogenesis; Principal Investigator; Prostatic Neoplasms; Protein Family; Research; Research Infrastructure; Resources; Role; Signal Transduction; Source; Testing; United States National Institutes of Health; cancer cell; cell motility; cost; in vivo; knock-down; molecular mass; prevent; small molecule; tumor progression

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. Gap junctions are conglomerations of cell-cell channels that are formed by a family of proteins, called connexins, which are designated according to molecular mass. They permit the direct passage of small molecules between adjoining cells. Our studies have shown that in invasive prostate tumors connexin32 and connexin43 remain intracellular whereas in well differentiated prostate tumors both connexins are assembled into gap junctions. Moreover, forced expression of both connexins in prostate cancer cells induces differentiation and inhibits growth in vitro and in vivo. Our studies have also shown that expression of anti-metastatic E-cadherin facilitates gap junction assembly, whereas expression of pro-invasive N-cadherin disrupts assembly. Our central hypothesis is that bidirectional signaling between cadherins and connexins is required to maintain the polarized and the differentiated state of epithelial cells and that gap junction assembly is the downstream target of signaling initiated by cadherins, with E-cadherin facilitating the assembly and N-cadherin promoting the disassembly. The proposed studies in aim 1 will determine how E-cadherin mediated cell-cell adhesion controls the assembly of connexins into gap junctions in prostate cancer cells. The hypothesis to be tested is that cadherin mediated cell-cell adhesion induces a signaling cascade, which modulates gap junction assembly. Wild type and extracellular domain deleted cadherins that are unable to induce cell-cell adhesion will be used. The proposed studies in aim 2 will determine the molecular mechanisms by which E-cadherin and N-cadherin modulate gap junction assembly differentially. This aim tests the hypothesis that E-cadherin facilitates gap junction assembly by preventing the endocytosis of connexins whereas N-cadherin promotes disassembly by inducing endocytosis. E-cadherin and N-cadherin will be knocked down in various prostate cancer cell lines in which connexins are either assembled into gap junctions or remain intracellular. Alternatively, wild type N-cadherin, and its chimeras that modulate cell motility differentially, will be expressed in Ecadherin expressing prostate cancer cell lines. These studies will enhance our understanding about the role of cadherins and connexins in the pathogenesis of prostate cancer.

该子项目是利用资源的众多研究子项目之一 由 NIH/NCRR 资助的中心拨款提供。子项目的主要支持 并且子项目的首席研究员可能是由其他来源提供的， 包括其他 NIH 来源。 子项目可能列出的总成本 代表子项目使用的中心基础设施的估计数量， NCRR 赠款不直接向子项目或子项目工作人员提供资金。 间隙连接是细胞-细胞通道的聚集体，由一系列蛋白质形成，称为 连接蛋白，根据分子质量命名。它们允许直接通过 相邻细胞之间的小分子。我们的研究表明，在侵袭性前列腺肿瘤中 connexin32 和 connexin43 保留在细胞内，而在分化良好的前列腺肿瘤中 连接蛋白组装成间隙连接。此外，两种连接蛋白的强制表达 前列腺癌细胞在体外和体内诱导分化并抑制生长。我们的研究有 还表明，抗转移性 E-钙粘蛋白的表达促进间隙连接组装，而 促侵袭性 N-钙粘蛋白的表达会破坏组装。我们的中心假设是双向 钙粘蛋白和连接蛋白之间的信号传导需要维持极化和 上皮细胞的分化状态，间隙连接组装是下游目标 信号传导由钙粘蛋白发起，E-钙粘蛋白促进组装，N-钙粘蛋白促进 拆解。目标 1 中拟议的研究将确定 E-钙粘蛋白如何介导细胞间相互作用 粘附控制前列腺癌细胞中连接蛋白组装成间隙连接。这 要测试的假设是钙粘蛋白介导的细胞间粘附诱导信号级联反应， 它调节间隙连接组装。野生型和胞外域删除的钙粘蛋白 将使用不能诱导细胞-细胞粘附的。目标 2 中拟议的研究将确定 E-钙粘蛋白和 N-钙粘蛋白调节间隙连接组装的分子机制 有区别地。该目的检验了 E-钙粘蛋白通过以下方式促进间隙连接组装的假设： 防止连接蛋白的内吞作用，而 N-钙粘蛋白通过诱导促进分解 内吞作用。 E-钙粘蛋白和N-钙粘蛋白将在多种前列腺癌细胞系中被敲低 这些连接蛋白要么组装成间隙连接，要么保留在细胞内。或者，野生 N-型钙粘蛋白及其差异调节细胞运动的嵌合体将在 Ecadherin 中表达 表达前列腺癌细胞系。这些研究将加深我们对 钙粘蛋白和连接蛋白在前列腺癌发病机制中的作用。