INTEGRATION OF ONCOGENIC SIGNALS BY THE NUCLEOLAR ARF-NPM NETWORK

通过核仁 ARF-NPM 网络整合致癌信号

• 批准号: 8265314
• 负责人: Jason Weber
• 金额: $ 30.59万
• 依托单位: WASHINGTON UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-07-01 至 2014-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8265314
• 关键词: Acute; Affect; Basic Science; Benign; Binding; Biogenesis; Biology; Cancer Biology; Cancer Patient; Cell Cycle; Cell Nucleolus; Cell Proliferation; Cellular biology; Clinical; Complex; Data; Genes; Growth; Human; In Vitro; Investigation; Knowledge; Label; Malignant Neoplasms; Mus; Mutate; Oncogenic; Organelles; Prevalence; Property; Proteins; Proto-Oncogenes; Ribosomes; Role; Second Primary Cancers; Signal Transduction; Time; Tumor Suppressor Proteins; Work; abstracting; base; cell growth; cell transformation; in vivo; inhibitor/antagonist; mutant; novel; nucleophosmin; prevent; protein expression; protein p68; stoichiometry; therapeutic target; tumor

ABSTRACT Initially described as an organelle contained within specific chromosomal regions, the nucleolus has advanced through the past century imparting much knowledge about cell and cancer biology along the way. Once hindered with the label as being the static center of ribosome biogenesis, a newfound appreciation for this visible organelle has been established in recent years. One of the most dynamic occupants of the mammalian nucleolus is the ARF tumor suppressor protein. Since its discovery, the mechanism behind ARF's tumor suppressive function has been under intense investigation. Initially touted as a bona fide inhibitor of the p53 negative regulator, Mdm2, more recent studies have identified a p53-independent role for ARF in suppressing tumor formation in mice and humans. Much of the more recent work has focused on the novel localization of ARF in the nucleolus, a seemingly benign organelle in terms of transformation properties. One of the least understood aspects of ARF biology is what is ARF doing in the nucleolus. Numerous labs, including ours, have identified the nucleophosmin (NPM) proto-oncogene as a nucleolar binding partner of ARF. Our preliminary data demonstrates that hypergrowth signals emanating from the loss of the Tsc1 tumor suppressor stimulate the protein expression of both NPM and ARF in an effort to influence ribosome synthesis rates. Additionally, basal nucleolar ARF proteins interact with a pool of NPM in the nucleolus and acute loss of these basal ARF molecules results in dysregulated NPM function and increased ribosome biogenesis. Loss of nucleolar ARF alters the landscape of the nucleolus, allowing for proteins, such as the p68 RNA helicase, to interact more readily with NPM to potentially promote ribosome biogenesis and cell transformation. We hypothesize that ARF resides in the nucleolus to tightly regulate ribosome biogenesis through the sensing of hypergrowth signals and to halt unwarranted NPM-p68 activities. Based on our preliminary data and our stated hypothesis, three specific aims are proposed: 1) Determine how oncogenic growth signals are interpreted by the nucleolar ARF-NPM complex, 2) Establish the physical and functional interaction of the p68 RNA helicase with NPM, and 3) Determine the in vitro and in vivo ability of ARF to act as a nucleolar checkpoint protein. PROJECT NARRATIVE The ARF tumor suppressor is the second most commonly mutated gene in human cancers, second only to p53. We are just beginning to appreciate how this critical tumor suppressor functions to prevent unwarranted cell growth and proliferation. We seek to understand the mechanism behind ARF's ability to regulate p53-independent growth arrest in vivo and to move these findings into a more clinical setting where novel ARF-targeted therapeutics might affect a broad spectrum of cancer patients. Thus, basic research into ARF biology is appropriate given its mutational prevalence in human cancers.

抽象的 核仁最初被描述为包含在特定染色体区域内的细胞器，现已发展为 在过去的一个世纪中，我们一路传授了许多有关细胞和癌症生物学的知识。一次 被标签为核糖体生物发生的静态中心所阻碍，这是对此的新发现 可见细胞器是近年来建立的。哺乳动物中最具活力的居住者之一 核仁是ARF肿瘤抑制蛋白。自发现以来，ARF肿瘤背后的机制 抑制功能一直在深入研究中。最初被吹捧为真正的 p53 抑制剂 负调节因子 Mdm2，最近的研究发现 ARF 在抑制 小鼠和人类的肿瘤形成。最近的大部分工作都集中在新颖的本地化上 核仁中的 ARF，从转化特性来看是一种看似良性的细胞器。最少的之一 ARF 生物学的已知方面是 ARF 在核仁中的作用。许多实验室，包括我们的实验室， 已确定核磷蛋白 (NPM) 原癌基因为 ARF 的核仁结合伴侣。我们的 初步数据表明，过度生长信号源自 Tsc1 肿瘤抑制因子的缺失 刺激 NPM 和 ARF 的蛋白质表达，以影响核糖体合成速率。 此外，基础核仁 ARF 蛋白与核仁中的 NPM 池相互作用，并且这些蛋白会急剧丧失 基础 ARF 分子导致 NPM 功能失调并增加核糖体生物发生。损失 核仁 ARF 改变核仁的结构，允许蛋白质（例如 p68 RNA 解旋酶） 更容易与 NPM 相互作用，从而潜在地促进核糖体生物合成和细胞转化。我们 假设 ARF 存在于核仁中，通过感知 过度生长信号并停止不必要的 NPM-p68 活动。根据我们的初步数据和我们声明的 假设，提出了三个具体目标：1）确定致癌生长信号如何被解释 核仁 ARF-NPM 复合物，2) 建立 p68 RNA 解旋酶的物理和功能相互作用 与 NPM 一起使用，以及 3) 确定 ARF 作为核仁检查点蛋白的体外和体内能力。项目叙述 ARF 肿瘤抑制基因是人类癌症中第二常见的突变基因，位居第二。 仅限p53。我们才刚刚开始了解这种关键的肿瘤抑制因子如何发挥作用 防止细胞不必要的生长和增殖。我们试图了解背后的机制 ARF 能够在体内调节不依赖于 p53 的生长停滞，并将这些发现转化为 新型 ARF 靶向疗法可能影响更广泛的临床环境 癌症患者。因此，考虑到 ARF 的突变性，对 ARF 生物学进行基础研究是合适的。 人类癌症的患病率。

项目成果

Nucleophosmin protein expression level, but not threonine 198 phosphorylation, is essential in growth and proliferation.

• DOI: 10.1038/onc.2009.178
• 发表时间: 2009-09-10
• 期刊: ONCOGENE
• 影响因子: 8
• 作者: Brady, S. N.;Maggi, L. B., Jr.;Winkeler, C. L.;Toso, E. A.;Gwinn, A. S.;Pelletier, C. L.;Weber, J. D.
• 通讯作者: Weber, J. D.

RNA helicase DDX5 is a p53-independent target of ARF that participates in ribosome biogenesis.

• DOI: 10.1158/0008-5472.can-11-1472
• 发表时间: 2011-11-01
• 期刊: Cancer research
• 影响因子: 11.2
• 作者: Saporita AJ;Chang HC;Winkeler CL;Apicelli AJ;Kladney RD;Wang J;Townsend RR;Michel LS;Weber JD
• 通讯作者: Weber JD

Cathepsin K-Cre causes unexpected germline deletion of genes in mice.

• DOI: 10.1371/journal.pone.0042005
• 发表时间: 2012
• 期刊: PloS one
• 影响因子: 3.7
• 作者: Winkeler CL;Kladney RD;Maggi LB Jr;Weber JD
• 通讯作者: Weber JD