Role of PC1, Pc2 and HDAC6 in cyst formation in ADPKD

PC1、Pc2 和 HDAC6 在 ADPKD 囊肿形成中的作用

• 批准号: 8767384
• 负责人: Valeriu Cebotaru
• 金额: $ 7.58万
• 依托单位: JOHNS HOPKINS UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-09-01 至 2015-01-04
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8767384
• 关键词: 5' -AMP-activated protein kinase; Address; Affect; Animal Model; Autophagocytosis; Autosomal Dominant Polycystic Kidney; Basic Science; Binding; Biochemistry; Calcium Signaling; Cancer cell line; Cell Polarity; Cell membrane; Cells; Combined Modality Therapy; Complex; Cyst; Cystic kidney; Data; Development; Doctor of Philosophy; Duct (organ) structure; EGF gene; Embryo; Epidemiology; Epidermal Growth Factor Receptor; Epithelial; Epithelial Cells; Epithelium; Exhibits; Five-Year Plans; Future; Gel; Growth; Hereditary Disease; Human; ITPR1 gene; K-Series Research Career Programs; Kidney; Knock-out; Knockout Mice; Lead; Link; Liquid substance; MDCK cell; Malignant Neoplasms; Mentors; Mentorship; Molecular Biology; Molecular Medicine; Mus; Mutation; Nephrology; Outcome; PKD1 gene; PKD2 gene; PKD2 protein; Pathway interactions; Phenotype; Physicians; Play; Polycystic Kidney Diseases; Proteins; Regulation; Renal tubule structure; Research; Research Proposals; Research Training; Role; STIM1 gene; Scientist; Signal Transduction; Testing; Universities; V2 Receptors; Vasopressins; apical membrane; base; cancer cell; career; experience; histone deacetylase 6; human FRAP1 protein; indexing; inhibitor/antagonist; insight; instructor; kidney epithelial cell; knock-down; mutant; new therapeutic target; novel; overexpression; polycystic kidney disease 1 protein; prevent; protein expression; public health relevance; receptor; response; skills; statistics; trafficking; tubacin

DESCRIPTION (provided by applicant): Valeriu Cebotaru, MD, is an Instructor in the Division of Nephrology at Johns Hopkins University. He seeks a Mentored Basic Science-Oriented Research Career Development Award in order to obtain essential skills and mentored research experience for an independent career as a physician scientist in the field of polycystic kidney disease. The research proposal details a five-year plan consisting of coursework in Molecular Medicine, Statistics and Epidemiology, mentorship by Dr. William Guggino, PhD and basic science research training in molecular biology and biochemistry with primary focus on autosomal dominant polycystic kidney disease (ADPKD). ADPKD is a hereditary disorder that affects 1:1000 to 1:500 people and is characterized by fluid-filled cysts that arise from renal tubules. ADPKD results from mutations in either the PKD1 or PKD2 gene, which encode the gene products polycystin 1 (PC1) and polycystin 2 (PC2), respectively. Although PC1 and PC2 have been studied intensively, information on how they function to promote tubulogenesis or how a malfunction of either protein leads to cyst formation is still emerging. Histone deacetylase 6 (HDAC6) expression and activity are increased in Pkd1 mutant renal epithelial cells, and we have found that HDAC6 levels are increased in Pkd2 knockout MEF cells, suggesting that an intact PC1-PC2 complex is required to regulate HDAC6. In PKD, the cystic epithelium has an increased proliferative index; interestingly, overexpression of HDAC6 promotes anchorage-independent proliferation, whereas knockdown of HDAC6 inhibits anchorage-independent proliferation in cancer cell lines. We propose a novel concept in which disruption of the PC1-PC2 complex as a result of mutations in the PKD1 or PKD2 gene leads to increased HDAC6 levels/activity and subsequent cyst formation; targeting HDAC6 activity could prevent cyst formation or perhaps slow down cyst growth. The specific aims of the research agenda are to: 1) To determine the role of the PC1, PC2, and HDAC6 interrelationship in cyst formation. The overall hypothesis of this Aim is that in the absence of PC1 or PC2, increased HDAC6 activity will promote cyst formation. 2) To assess the impact of HDAC6 binding to PC2. The overall hypothesis of this Aim is that aberrant degradation and trafficking of PC2 is regulated by HDAC6 and by additional signal transduction systems regulated by PC1. 3) To define the role of HDAC6 in tubule function. The overall hypothesis of this Aim is that increased activity of HDAC6 will lead to aberrant calcium signaling and cell polarity in ADPKD, two critical epithelial functions that are dysregulated in ADPKD. Currently, there is no cure for ADPKD. One promising therapy involves the vasopressin V2 receptor antagonist, which inhibits cyst development in animal models of ADPKD and has been tested in humans but has not yet been approved as a therapy. However, given the multitude of pathways mis-regulated in ADPKD, a combination therapy that targets different pathways may be more efficacious. Our hypothesis is that disruption of the PC1-PC2 complex as a result of mutations in the PKD1 or PKD2 gene will lead to increased HDAC6 level/activity and could subsequently lead to cyst formation; targeting HDAC6 activity could prevent cyst formation or perhaps slow down cyst growth. This pre-translational proposal will study how the PC1-PC2 complex regulates cyst formation through HDAC6 in both 3D culture and animal models of PKD. HDAC6 inhibitors are being tested intensively in the treatment of various malignancies and could be considered as an ADPKD treatment in the future.

描述（由申请人提供）：医学博士Valeriu Cebotaru，是约翰·霍普金斯大学肾脏科学系的讲师。他寻求一个受过指导的基础科学研究职业发展奖，以获得基本的技能，并为多囊肾脏病领域的医师科学家提供独立职业的研究经验。该研究建议详细介绍了一项五年计划，该计划包括分子医学，统计和流行病学的课程，威廉·古金诺（William Guggino）博士，博士学位和分子生物学的基础科学研究培训，主要关注常染色体显性多囊性肾脏病（ADPKD）。 ADPKD是一种影响1：1000至1：500人的遗传性疾病，其特征是由肾小管引起的充满液体的囊肿。 ADPKD分别由PKD1或PKD2基因中的突变产生，该突变分别编码了基因产物Polycystin 1（PC1）和Polycystin 2（PC2）。尽管已经对PC1和PC2进行了深入的研究，但有关它们如何促进肾变发生的功能或任何两种蛋白质的功能的信息仍在出现。 PKD1突变体肾上皮细胞中组蛋白脱乙酰基酶6（HDAC6）的表达和活性增加，我们发现PKD2基因敲除MEF细胞中HDAC6水平升高，这表明需要完整的PC1-PC2复合物来调节HDAC6。在PKD中，囊性上皮具有增加的增殖指数。有趣的是，HDAC6的过表达促进了独立的锚固增殖，而HDAC6的敲低抑制了癌细胞系中锚定非依赖性的增殖。我们提出了一个新颖的概念，其中PC1-PC2复合物因PKD1或PKD2基因突变而导致HDAC6水平/活性以及随后的囊肿形成增加。靶向HDAC6活性可以防止形成囊肿或减慢囊肿的生长。研究议程的具体目的是：1）确定PC1，PC2和HDAC6相互关系在囊肿形成中的作用。该目标的总体假设是，在没有PC1或PC2的情况下，HDAC6活性增加将促进囊肿的形成。 2）评估HDAC6与PC2结合的影响。该目标的总体假设是，PC2的异常降解和运输受HDAC6和PC1调节的其他信号转导系统调节。 3）定义HDAC6在小管功能中的作用。该目标的总体假设是，HDAC6的活性增加将导致ADPKD中异常的钙信号传导和细胞极性，这两个关键上皮功能在ADPKD中失调。目前，ADPKD无法治愈。一种有前途的疗法涉及加压素V2受体拮抗剂，该疗法抑制了ADPKD动物模型中的囊肿发展，并已在人类中进行了测试，但尚未被批准作为治疗。但是，鉴于ADPKD中的多种途径错误，靶向不同途径的组合疗法可能更有效。我们的假设是，由于PKD1或PKD2基因突变，PC1-PC2复合物的破坏将导致HDAC6水平/活性增加，并随后导致囊肿形成。靶向HDAC6活性可以防止形成囊肿或减慢囊肿的生长。这项预先翻译的建议将研究PC1-PC2复合物如何在PKD的3D培养物和动物模型中通过HDAC6调节囊肿形成。 HDAC6抑制剂在治疗各种恶性肿瘤方面进行了深入的测试，将来可以被视为ADPKD治疗。