REGULATION OF AURORA-A KINASE ACTIVITIES BY AURORA-A INTERACTING PROTEINS

这个子项目是许多利用 由NIH/NCRR资助的中心赠款提供的资源。子项目和 研究者（PI）可能从另一个NIH来源获得了主要资金， 因此可以在其他CRISP条目中表示。所列机构为 研究中心，而研究中心不一定是研究者所在的机构。 癌症研究人员面临的一个主要挑战是开发显着提高治愈率的技术。 只有当我们更充分地了解癌症的病理生理学，才能发现新的抗癌药物，并更好地整合药物基因组学，才能实现这一目标。 Aurora-A在细胞周期和有丝分裂过程中调节多个过程，包括中心体成熟、有丝分裂进入、核膜破裂、双极纺锤体形成和定向、胞质分裂和细胞极性以实现不对称细胞分裂。因此，发现Aurora-A在大量癌症中扩增并不奇怪，特别是白血病和上皮来源的癌症，即乳腺癌、结肠癌、膀胱癌、卵巢癌和胰腺癌。 Aurora-A可能促进肿瘤的发生、发展和转移，其功能障碍可能以多种不同的方式导致细胞转化和癌症。 通过与不同的Aurora-A相互作用蛋白（AurAIP）相互作用，Aurora-A可以组装成不同的信号传导模块，其失调可以将细胞转化为不同的癌症类型，这些癌症类型对Aurora-A抑制剂有不同的反应。 因此，迫切需要了解这些途径是如何激活的，以及它们激活的结果，以便了解它们在肿瘤形成中的作用并制定治疗策略。 我们实验室的长期目标是开发一种有效的诊断和治疗方法，用于利用Aurora A激酶（Aurora-A）途径治疗癌症。 我们建议利用我们对Aurora-A相互作用蛋白（Aurora-A interacting proteins，AurAIPs）如何激活Aurora-A的理解来开发翻译应用，这将增强人群靶向治疗的潜力。 我们的实验室已经表征了几种致癌AurAIP之一，TPX 2作为Aurora-A的第一个激活剂。 我们已经确定HURP作为另一种AurAIP，激活爪蟾卵提取物中的Aurora-A。 我们将利用我们实验室开发的新方法来了解Aurora-A如何在有丝分裂的各个步骤中受到这些结构无关的AurAIP的调控。 了解每个Aurora-A激活途径如何与肿瘤发生联系将有助于快速诊断，并确保Aurora-A途径用于抗癌治疗的适当人群靶向。 A.1.研究AurAIPs与Aurora-A的相互作用是如何调节的 我们发表的研究已经描述了AurAIP，TPX 2，如何与Aurora-A时空相互作用。 简而言之，活性TPX 2与Aurora-A相互作用并将Aurora-A靶向纺锤体。 Importin与TPX 2的结合阻止TPX 2与Aurora-A相互作用。 Ran是纺锤体组装的空间调节剂，其可以从Importin的抑制性结合中释放TPX 2。 在这个目标中，我们将描述其他AurAIP与Aurora-A的相互作用如何在细胞周期进程中受到调节。 A.2. 检查Aurora-A与其底物的结合是否受AurAIPs的调节 为了发挥分子支架的作用，AurAIPs应该能够通过局部浓缩蛋白质并将Aurora-A定位在其底物附近来提高信号传导的效率。 我们将研究AurAIPs是否也通过选择性地将特异性底物引入Aurora-A来调节Aurora-A的通路特异性。 A.3.研究AurAIPs如何调节Aurora-A功能 虽然已经有很多努力致力于研究个别的AurAIPs的功能，很少有研究已经针对了解这些AurAIPs的行动是如何相互耦合，以及这种耦合是否是重要的Aurora-A功能的调节。 解决这个问题的研究一直受到缺乏检测方法的阻碍，使人们能够解决交叉调节的复杂问题。 我们计划使用一些体外和体内试验来研究四种AurAIP如何协调调节Aurora-A功能。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. A major challenge facing cancer researchers is the development of technologies that significantly increase cure rates. This can only be achieved when we more fully understand cancer pathophysiology so that new anticancer agents can be discovered and better integration of pharmacogenomics can be developed. Aurora-A regulates multiple processes during the cell cycle and mitosis, including centrosome maturation, mitosis entry, nuclear envelope breakdown, bi-polar spindle formation and orientation, cytokinesis and cell polarity for asymmetric cell division. Thus, it is not surprising that Aurora-A is found to be amplified in a plethora of cancers particularly leukemia and those of epithelial origin, namely, breast, colon, bladder, ovarian, and pancreatic. Aurora-A may promote tumor initiation, progression and metastasis, and its malfunction may lead to cell transformation and cancer in a number of different ways. By interacting with distinct Aurora-A interacting proteins (AurAIPs), Aurora-A could assemble into different signaling modules, and its misregulation could transform cells into different cancer types that would differentially respond to Aurora-A inhibitors. Thus, there is an urgent need to understand how these pathways are activated and the result of their activation in order to understand their role in neoplasia and develop strategies for treatment. The long-term goal of our lab is to develop an effective diagnosis and therapeutic approach for cancer treatment utilizing the Aurora A kinase (Aurora-A) pathways. We proposed to use our understanding of how Aurora-A is activated by Aurora-A interacting proteins (AurAIPs) to develop translational applications, which will enhance the potential for population-targeted therapy. Our lab has characterized one of the several oncogenic AurAIPs, TPX2 as the first activator identified for Aurora-A. We have identified HURP as another AurAIP that activates Aurora-A in Xenopus egg extract. We will utilize novel assays developed by our lab to understand how Aurora-A is regulated by these structurally-unrelated AurAIPs in the various steps of mitosis. Understanding how each Aurora-A activation pathway links to tumorigenesis will facilitate rapid diagnosis and ensure appropriate population targeting of the Aurora-A pathway for anti-cancer therapy. A.1. Examine how AurAIPs interaction with Aurora-A is regulated Our published studies have characterized how one AurAIP, TPX2, spatiotemporally interacts with Aurora-A. Briefly, active TPX2 interacts with Aurora-A and targets Aurora-A to the spindle. Binding of Importin ¿/¿ to TPX2 prevents TPX2 from interacting with Aurora-A. Ran is a spatial regulator of spindle assembly that can release TPX2 from the inhibitory binding of Importin ¿/¿. In this aim, we will characterize how the interaction of other AurAIPs with Aurora-A is regulated in cell cycle progression. A.2. Examine whether the association of Aurora-A with its substrates is regulated by AurAIPs To function as molecular scaffolds, AurAIPs should be able to increase the efficiency of signaling by locally concentrating proteins and positioning Aurora-A in close proximity to its substrates. We will investigate whether AurAIPs also regulate pathway-specificity of Aurora-A by selectively bringing specific substrate(s) to Aurora-A. A.3. Examine how AurAIPs regulate Aurora-A function Although much effort has been devoted to studying the functions of AurAIPs individually, very few studies have been directed at understanding how the actions of these AurAIPs are coupled with one another and whether this coupling is important in the regulation of Aurora-A function. Studies addressing this question have been hampered by a lack of assays allowing one to address the complex issue of cross regulation. We plan to use a number of in vitro and in vivo assays to study how four AurAIPs might coordinately regulate Aurora-A function.