MOLECULAR DISSECTION OF TUMOR INVASION

描述：(申请人描述) 这个项目的长期目标是提高我们的诊断和 阻断人类癌症最致命的阶段，获得侵袭性 州政府。对细胞入侵的分子机制知之甚少，因为 还没有开发出强大的模型系统来分析这一过程。我们 利用果蝇遗传学发展卵室形态发生作为一种 用于剖析细胞分子机制的强大细胞和组织模型 入侵。卵室对于分析细胞入侵来说是例外的，因为 它们简单的架构提供了一种易于评分的测试方法。这项建议 重点介绍了保守的抑癌基因Discs-Large(DLG)在肿瘤中的作用 抑制细胞入侵。人DLG同源基因SAP97与APC结合最多 结直肠癌中常见的突变基因，而另一个 人地高辛同源基因ZO-1在大多数侵袭性肿瘤中特异性缺失 乳房肿瘤。DLG、SAP97和ZO-1是具有三个PDZ的支架蛋白 域、SH3域和GUK域。PDZ域对以下各项至关重要 抑制果蝇的细胞入侵，并直接与 特异性地参与抑制果蝇和果蝇的细胞入侵 人体组织，包括细胞黏附分子FasII/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尚不清楚。 这些结果表明，D1g组织和调节了大量的 控制正常细胞迁移和抑制肿瘤细胞的蛋白质 入侵。以下特定目的利用分子组合 遗传学、细胞生物学和生物化学来深入了解D1g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。目标1是确定单个DIG结构域在 阻止细胞入侵。目的2是确定PDZ结合蛋白FasII是如何 KEK1与DLG协同阻断细胞侵袭。目标3是确定 DLG和EGFR信号通路之间的关键相互作用。目标4是 确定DLG侵袭细胞绕过正常细胞的细胞途径 迁徙路径。目标5是表征额外的候选D1G PDZ结合 蛋白质。这个模型系统很强大，因为关键分子和一个 类似于人类疾病的细胞过程已经被发现。这个 能够分析保守的抑癌基因和癌基因 细胞侵袭实验将揭示一种超分子的结构和功能 阻止细胞入侵的组件。这项工作很可能会发现细胞和 阻断肿瘤细胞侵袭的分子靶点作为癌症治疗的手段。

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.