A novel determinant of prostate cancer growth

项目摘要/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 转移性帽子的治疗失败了。通过完全不同的方式发挥作用的新疗法的可操作目标 需要机制、对当前治疗的旁路耐药和控制生物学来驱动帽的进展。 迫切需要提高患者的存活率。长期目标是瞄准控制帽子细胞的机制(S) 用于治疗干预的增殖和帽状生长。我们的目标是获得所需的洞察力 确定抑制有丝分裂期激酶柠檬酸激酶(CIT)作为新的信号通路的可行性和适用性 帽子治疗。我们推测，CIT及其激酶活性控制CAP细胞的机制(S) 可以利用扩散作为替代的CAP治疗方法，以克服对传统CAP的获得性耐药性 治疗。这一假说是基于我们实验室的初步工作提出的，该工作证实了 Cit及其激酶活性作为帽子生长的一个新的关键决定因素。基本原理是这项工作可能会 一种急需的新型帽子疗法的基础，该疗法专门针对疾病期间的生长 进步。我们将通过追求三个具体目标来检验这一假说：1)确定控制的机制(S) CIT蛋白表达，2)确定CIT传递攻击性帽子行为的方式，以及3) 确定在CAP进展期间靶向CIT的治疗潜力。目标1将使用分子生物学 细胞生物学方法描述新的E2F2-Skp2信号轴的分子机制 诱导CIT蛋白水平，特别是Skp2介导的p27降解的作用。在目标2中，我们 将通过分离CIT蛋白相互作用体来定义CIT传递攻击性帽子行为的方式 以及介导帽细胞增殖的CIT激酶底物。整合酶底物测定法及其近似性 将进行连接分析和质谱分析。目标3将定义治疗潜力 遗传或药物CIT对CAP细胞系异种移植、PDX和新鲜患者组织生长的抑制作用 于ADT前、后取外植体，并与按护理标准所达到的疗效进行比较。建议数 研究具有创新性，因为它专注于一种完全不同的治疗上限的方法：针对 新型CAP生长调节剂抑制晚期CAP进展和旁路CAP治疗的作用 抵抗。这一贡献意义重大，因为它是预期中的一系列研究的第一步 导致开发专门针对以下分子机制的新的治疗模式 控制致命上限的进展。关于预期结果，拟议的研究将说明 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 进步。这些结果将产生重大的积极影响，因为它们将从根本上推动 总体上了解控制上限增长的机制，并提供CIT作为一种全新的 特别是针对急需的新型帽子治疗方法，在功能上有明确的目标。

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.