Elucidating a Novel Mechanism for SPOP in Suppressing Prostate Tumorigenesis

阐明 SPOP 抑制前列腺肿瘤发生的新机制

• 批准号: 9223978
• 负责人: Jinfang Zhang
• 金额: $ 16.88万
• 依托单位: BETH ISRAEL DEACONESS MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-08-01 至 2019-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9223978
• 关键词: Award; Basic Science; Binding; Biochemical; Biological Assay; Biological Process; COPS5 gene; Cancer Biology; Cancer Diagnostics; Cancer Etiology; Cancer Patient; Cancerous; Cell Aging; Cells; Cessation of life; Complex; Country; Cullin Proteins; Data; Deubiquitinating Enzyme; Deubiquitination; Development; Diagnosis; Disease; Ectopic Expression; Family; Family member; Future; Genetic Status; Genetically Engineered Mouse; Genome Stability; Goals; Half-Life; Human; In Vitro; Individual; Israel; Link; Machado-Joseph Disease; Malignant Neoplasms; Malignant neoplasm of prostate; Mediating; Medical center; Meprin; Modification; Molecular; Molecular and Cellular Biology; Mutation; Neoplasm Metastasis; Oncogenes; Outcome; Pathway interactions; Peptide Hydrolases; Phase; Phenotype; Physiological; Play; Polyubiquitination; Problem Solving; Process; Prostate Cancer therapy; Proteins; Recurrence; Regulation; Research; Role; Scientist; Signal Pathway; Signaling Protein; Somatic Mutation; Stem cells; Time; Tissues; Training; Translational Research; Tumor Suppressor Proteins; Ubiquitin; Ubiquitination; United States; anticancer research; authority; base; cancer stem cell; cancer therapy; career; cullin-3; design; experimental study; in vivo; insight; medical schools; men; metalloenzyme; mouse model; novel; novel therapeutics; ovarian neoplasm; pluripotency; preclinical study; prostate carcinogenesis; protein function; self-renewal; skills; stemness; targeted treatment; transcription factor; tumor; tumor progression; tumorigenesis; ubiquitin C-terminal hydrolase; ubiquitin-protein ligase; ubiquitin-specific protease

Abstract: Recent intensive studies revealed that recurrent somatic mutation is also a key feature of prostate cancer. Notably, mutations in SPOP (Speckle-type POZ protein), which functions as a substrate-interacting adaptor for the Cullin 3-based E3 ubiquitin ligase, occur in 10%-15% of primary human prostate cancers, representing as the molecular feature of one of the seven sub-types of prostate cancer (PrCa). However, the molecular mechanism and physiological role of SPOP in regulating prostate tumorigenesis remains largely elusive. Moreover, although several downstream ubiquitin substrates have been identified in recent years for Cullin 3SPOP, the upstream signaling pathway to control SPOP stability is largely unknown. Hence, the major goal of this proposal is to explore the upstream regulator as well as to uncover a novel tumor suppressor role of the Cullin 3SPOP ubiquitin E3 ligase in controlling tumorigenesis in the prostate cancer setting. To this end, I have obtained preliminary data showing that the deubiquitinating enzyme OTUD3, but not other OTUD family member, specifically interacts and dequbiquitinates SPOP. More importantly, I identified Nanog, a transcription factor that plays a pivotal role in the maintance of self-renewal and stemness of cancerous cells, as a novel ubiquitin substrate of SPOP. This critical finding, for the first time, links the tumor suppressive role of SPOP E3 ligase to the regulation of prostate cancer stem cells. In this proposal, I plan to: 1) Characterize OTUD3 as an upstream regulator that positively regulates SPOP stability largely through deubiquitination of SPOP; 2) Determine the physiological role of Cullin 3SPOP in suppressing prostate tumorigenesis largely through poly- ubiquitination and degradation of Nanog; 3) Determine whether and how SPOP mutation contributes prostate cancer development and metastasis in vivo. The long-term goals of my career are to apply the insights of molecular and cellular biology to understand the physiological significance of deregulated proteolytic pathways that are important in the development of human malignancies, especially in prostate cancer, and to search for proper druggable targets. This K99/R00 award will provide protected time for me to pursue the novel hypotheses of this proposal, obtain new skill sets to execute experiments and solve problems. In addition, the award will also allow me to focus my efforts on independently conducting basic and translational research, and to train future young scientists in the cancer biology field. Should I receive this award, I will pursue this research at Beth Israel Deaconess Medical Center (BIDMC), Harvard Medical School, where authorities in the fields of ubiquitin E3 ligase and prostate cancer research locate. The outcome of the proposed studies will help elucidate whether the newly identified SPOP mutations could directly regulate prostate tumorigenesis in vivo, and whether blocking its downstream pluripotency maintaining transcription factor Nanog could retard prostate cancer progression.

摘要： 最近的深入研究表明，复发性体细胞突变也是前列腺癌的一个关键特征。 值得注意的是，SPOP（斑点型POZ蛋白）中的突变，其作为底物相互作用的衔接子， 基于Cullin 3 E3泛素连接酶存在于10%-15%的原发性人前列腺癌中，代表为 前列腺癌的七种亚型之一（PrCa）的分子特征。然而，分子 SPOP在调节前列腺肿瘤发生中的机制和生理作用仍然很难解释。 此外，尽管近年来已经鉴定了Cullin的几种下游泛素底物， 3SPOP，控制SPOP稳定性的上游信号通路在很大程度上是未知的。因此， 这项提议是为了探索上游调节因子，并揭示一种新的肿瘤抑制作用， Cullin 3SPOP泛素E3连接酶在前列腺癌背景下控制肿瘤发生。为此，我 获得的初步数据显示，去泛素化酶OTUD 3，而不是其他OTUD家族 成员，特别是相互作用和dequbiquitinates SPOP。更重要的是，我发现了纳诺格， 在维持癌细胞的自我更新和干细胞性方面起关键作用的因子，作为一种新的 SPOP的泛素底物。这一重要发现首次将SPOP E3的肿瘤抑制作用联系起来， 连接酶对前列腺癌干细胞的调控。在这个提案中，我计划：1）将OTUD 3描述为 主要通过SPOP的去泛素化正向调节SPOP稳定性的上游调节因子; 2） 确定Cullin 3SPOP在抑制前列腺肿瘤发生中的生理作用，主要是通过多聚- Nanog的泛素化和降解; 3）确定SPOP突变是否以及如何有助于前列腺 体内癌症发展和转移。我职业生涯的长期目标是应用 分子和细胞生物学，以了解失调的蛋白水解途径的生理意义 在人类恶性肿瘤，特别是前列腺癌的发展中很重要， 合适的药物目标这个K99/R 00奖将为我提供受保护的时间来追求小说 该提案的假设，获得新的技能来执行实验和解决问题。此外该 该奖项还将使我能够专注于独立开展基础和转化研究， 培养未来的癌症生物学领域的年轻科学家。如果我获得这个奖项，我将继续努力， 在哈佛医学院贝丝以色列女执事医疗中心（BIDMC）进行的研究， 泛素E3连接酶和前列腺癌研究领域。拟议研究的结果将有助于 阐明新鉴定的SPOP突变是否可以直接调节体内前列腺肿瘤发生， 以及阻断其下游的多能性维持转录因子Nanog是否可以延缓前列腺增生， 癌症进展