MOLECULAR DISSECTION OF TUMOR INVASION

描述：（申请人的描述） 该项目的长期目标是提高我们的诊断能力， 阻止人类癌症最致命的阶段，获得侵入性的 状态对细胞侵袭的分子机制知之甚少， 还没有开发出用于分析该过程的强大的模型系统。我们 利用果蝇遗传学来发展卵室形态发生， 强大的细胞和组织模型，用于解剖细胞的分子机制 入侵卵室是分析细胞入侵的例外，因为 它们简单的结构提供了易于评分的测定。 这项建议 重点关注保守的肿瘤抑制因子椎间盘-大（Dlg）在 抑制细胞侵袭。人Dlg同源物SAP 97结合APC，最大程度地结合APC。 结肠直肠癌中常见的突变基因，而另一个 人类Dig同系物ZO-1在大多数侵袭性肿瘤中特异性丢失， 乳腺肿瘤Dlg、SAP 97和ZO-1是具有三个PDZ的支架蛋白 结构域、SH 3结构域和GuK结构域。PDZ结构域对于 抑制果蝇的细胞入侵，并直接与蛋白质结合， 在果蝇和果蝇中， 人组织，包括细胞粘附分子Fas II/NCAM和EGF 受体（EgfR）。 另一种保守的分子Kekkonl（Keki）与两者结合， Dlg PDZ和EgfR，但其在细胞侵袭中的作用仍有待确定。 这些结果表明，D1 g组织和调节一个大的组装， 控制正常细胞迁移和抑制肿瘤细胞的蛋白质 入侵 以下具体目的利用分子生物学的组合。 遗传学、细胞生物学和生物化学，以深入了解D1 g是如何 蛋白质家族组织和调节超分子组装，以防止 细胞入侵目的1是确定单个Dig结构域在 阻止细胞侵入。目的2是确定PDZ结合蛋白Fas II Kek 1与Dlg共同阻断细胞侵袭。目标3：确定 Dlg和EgfR信号通路之间的关键相互作用。目标4： 确定Dlg侵袭细胞绕过正常细胞的细胞途径， 迁移路径。目的5是表征额外的候选D1 g PDZ结合 proteins.这个模型系统是强大的，因为关键分子和 类似于人类疾病的细胞过程已经被确定。 的 分析保守的肿瘤抑制基因和癌基因的能力， 细胞侵袭试验将揭示超分子的结构和功能， 阻止细胞入侵的组装。这项工作很可能揭示细胞和 分子靶点阻断肿瘤细胞侵袭作为癌症治疗手段。

DESCRIPTION: (Applicant's Description) The long-term goal of this project is to improve our ability to diagnose and block the most lethal phase of human cancer, acquisition of the invasive state. Little is known about the molecular mechanisms of cell invasion because no powerful model systems have been developed for analyzing this process. We have used Drosophila genetics to develop egg chamber morphogenesis as a powerful cell and tissue model for dissecting the molecular mechanisms of cell invasion. Egg chambers are exceptional for analyzing cell invasion because their simple architecture provides an easy to score assay. This proposal focuses on the role of the conserved tumor suppressor Discs-large (Dlg) in suppressing cell invasion. The human Dlg homolog SAP97 binds to APC, the most commonly mutated gene in colorectal cancer, while another human Dig homolog, ZO-1, is specifically lost in the majority of invasive breast tumors. Dlg, SAP97, and ZO-1 are scaffolding proteins have three PDZ domains, an SH3 domain, and a GuK domain. The PDZ domains are crucial for suppressing cell invasion in Drosophila, and directly bind to proteins that are specifically involved in suppressing cell invasion in both Drosophila and human tissues, including the cell adhesion molecules FasII/NCAM and the Egf receptor (EgfR). Another conserved molecule, Kekkonl (Keki), binds to both Dlg PDZ and EgfR, but it role in cell invasion remains to be established. These results suggest that D1g organizes and regulates a large assembly of proteins in controlling normal cell migration and suppressing tumor cell invasion. The following specific aims utilize a combination of molecular genetics, cell biology, and biochemistry to obtain insight into how the D1g family of proteins organize and regulate a supramolecular assembly to prevent cell invasion. Aim 1 is to determine the role of individual Dig domains in blocking cell invasion. Aim 2 is to determine how PDZ-binding proteins FasII and Kek1 cooperate with Dlg to block cell invasion. Aim 3 is to determine critical interactions between Dlg and the EgfR signaling pathway. Aim 4 is to determine the cellular routes by which Dlg invasive cells bypass normal migration pathways. Aim 5 is characterize additional candidate D1g PDZ-binding proteins. This model system is strong because both key molecules and a cellular process that resembles human disease have been identified. The ability to analyze conserved tumor suppressors and oncogenes in a powerful cell invasion assay will reveal the structure and function of a supramolecular assembly that blocks cell invasion. This work is likely to uncover cell and molecular targets to block tumor cell invasion as a means of cancer therapy.