A novel determinant of prostate cancer growth

项目总结/摘要 前列腺癌（CaP）将在2020年导致超过33，000名美国男性死亡，因为系统性 转移性CaP的治疗失败。新疗法的可行靶点， 机制，旁路对当前疗法的抗性，以及驱动CaP进展的控制生物学是必要的。 以提高患者生存率。长期目标是针对控制CaP细胞的机制 增殖和CaP生长用于治疗干预。我们的目标是获得所需的见解， 确定抑制有丝分裂激酶柠檬酸激酶（CIT）的作用作为新的 CaP治疗。我们推测CIT及其激酶活性控制CaP细胞的机制可能与CIT的作用机制有关。 增殖可用作替代性CaP治疗以克服对常规CaP的获得性抗性 治疗这一假设是根据我们实验室的初步工作制定的， CIT及其激酶活性作为CaP生长的新的关键决定因素。理由是，这项工作可能奠定 一种急需的新型CaP治疗剂的基础，该治疗剂在疾病期间特异性靶向CaP生长 进展我们将通过追求3个具体目标来测试这一假设：1）定义控制 CIT蛋白表达，2）确定CIT传递侵袭性CaP行为的方式，和3） 确定CaP进展期间靶向CIT的治疗潜力。AIM 1将使用分子生物学 和细胞生物学方法来描绘新的E2 F2-Skp 2信号轴的分子机制， 诱导CIT蛋白水平，特别是Skp 2介导的p27降解的作用。在目标2中， 将通过分离CIT蛋白相互作用组来定义CIT传递侵袭性CaP行为的方式 和介导CaP细胞增殖的CIT激酶底物。整合的激酶底物测定和邻近性 将进行与质谱联用的连接测定。目标3将定义 对CaP细胞系异种移植物、PDX和新鲜患者组织生长的遗传或药理学CIT抑制 在ADT之前和之后取出，并将其功效与通过标准护理实现的功效进行比较。拟议 这项研究是创新的，因为它专注于一种完全不同的治疗方法：靶向 新型CaP生长调节剂抑制晚期CaP进展和绕过CaP治疗的作用 阻力这一贡献意义重大，因为它是预期的连续研究的第一步 导致开发新的治疗方式，专门针对分子机制， 控制致命的CaP进展。关于预期成果，拟议的研究将说明如何 CIT控制CaP细胞增殖并确立其作为CaP期间急需的治疗靶点的价值 进展这些结果将产生重大的积极影响，因为它们将从根本上推进 控制CaP生长的机制的知识，一般来说，并提供CIT作为一个全新的， 功能上不同的目标，迫切需要的新的帽治疗，特别是。

Project Summary/Abstract Prostate cancer (CaP) will cause the deaths of more than 33,000 American men in 2020 because systemic treatments for metastatic CaP fail. Actionable targets for novel treatments that work via entirely different mechanisms, bypass resistance to current therapies, and control biology that drives CaP progression are needed urgently to improve patient survival. The long-term goal is to target the mechanism(s) that control CaP cell proliferation and CaP growth for therapeutic intervention. Our objective here is to derive the insights needed to determine the feasibility and applicability of inhibiting the action of the mitotic kinase citron kinase (CIT) as novel CaP treatment. We hypothesize that the mechanism(s) by which CIT, and its kinase activity, control CaP cell proliferation can be exploited as alternative CaP treatment to overcome acquired resistance to conventional CaP therapies. This hypothesis is formulated based on preliminary work produced in our laboratory, which identified CIT and its kinase activity as a novel critical determinant of CaP growth. The rationale is that this work may lay the foundation of a much-needed novel CaP therapeutic that targets specifically CaP growth during disease progression. We will test this hypothesis by pursuing 3 Specific Aims: 1) to define the mechanism(s) that control CIT protein expression, 2) to determine the manner in which CIT conveys aggressive CaP behavior, and 3) to determine the therapeutic potential of targeting CIT during CaP progression. Aim 1 will use molecular biology and cell biology approaches to delineate the molecular mechanism by which the novel E2F2-Skp2 signaling axis induces CIT protein levels, and specifically the role of Skp2-mediated degradation of p27 herein. In Aim 2, we will define the manner in which CIT conveys aggressive CaP behavior by isolating the CIT protein interactome and CIT kinase substrates that mediate CaP cell proliferation. Integrated kinase substrate assays and proximity ligation assays coupled with mass spectrometry will be performed. Aim 3 will define the therapeutic potential of genetic or pharmacological CIT inhibition on the growth of CaP cell line xenografts, PDXs and fresh patient tissue explants before and after ADT, and compare its efficacy to that achieved by the standard of care. The proposed research is innovative because it focuses on an entirely different approach to CaP treatment: targeting the action of a novel regulator of CaP growth to inhibit progression of advanced CaP and to bypass CaP treatment resistance. This contribution is significant because it is the first step in a continuum of research that is expected to lead to the development of novel treatment modalities that target specifically the molecular mechanisms that control lethal CaP progression. With respect to expected outcomes, the proposed studies will delineate how CIT controls CaP cell proliferation and establish its value as much-needed therapeutic target during CaP progression. These results will have a significant positive impact because they will fundamentally advance knowledge of the mechanisms that control CaP growth, in general, and provide CIT as an entirely new and functionally distinct target for much-needed novel Cap treatments, specifically.