Defining novel pathways that arrest genetically unstable tetraploid cells

定义阻止遗传不稳定四倍体细胞的新途径

• 批准号: 8321030
• 负责人: NEIL J. GANEM
• 金额: $ 14.99万
• 依托单位: DANA-FARBER CANCER INST
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-08-16 至 2013-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8321030
• 关键词: Address; Advisory Committees; Agar; Applications Grants; Area; Award; Biochemical; Bioinformatics; Biological; Biological Assay; Candidate Disease Gene; Cell Cycle; Cell Cycle Arrest; Cell Cycle Progression; Cell Proliferation; Cell division; Cells; Cellular biology; Committee Members; Cytokinesis; Cytoskeleton; DNA Damage; Dana-Farber Cancer Institute; Data; Defect; Development; Environment; Enzymes; Faculty; Failure; Fluorescence Microscopy; Foundations; Future; G1 Arrest; Gene Expression Profiling; Genes; Goals; Growth; Housing; Human; Human Cell Line; In Vitro; Individual; Institution; Lead; MDM2 gene; Malignant Neoplasms; Mass Spectrum Analysis; Medial; Medical; Mentors; Microarray Analysis; Mitosis; Mutate; Nature; Pathway interactions; Pediatric Oncology; Phase; Positioning Attribute; Proliferating; Protein Biochemistry; Proteins; Publications; RNA Interference; Regulation; Research; Research Personnel; Research Training; Resources; Role; Schools; Screening Result; Screening procedure; Signal Pathway; Signal Transduction; Small Interfering RNA; Sorting - Cell Movement; Stress; System; Testing; Tetraploidy; Time; Training; Tumor Suppression; Tumor Suppressor Proteins; Ubiquitin; Work; base; cancer cell; cancer therapy; cancer type; career; experience; feeding; genome wide association study; genome-wide; in vitro activity; in vivo; innovation; interest; meetings; mouse model; novel; overexpression; prevent; programs; research study; response; tumor; tumorigenesis

DESCRIPTION (provided by applicant): Research: Tetraploid cells, which are a common byproduct of cell division failures, are genetically unstable and have the capacity to facilitate tumorigenesis. Consequently, cells possess p53-dependent tumor suppression mechanisms that limit the further proliferation of these cells by promoting a durable G1 cell cycle arrest. However, unlike other common cellular insults that activate p53 and promote G1 arrest, such as the DNA damage response, the mechanisms governing G1 arrest in response to tetraploidy remain largely unexplored. A major goal of this proposal is to uncover how cells 'sense' cellular changes associated with tetraploidy and then relay that information into the p53 pathway to prevent cell cycle progression. To address this fundamental question, I have developed a novel genome-wide RNAi screening assay to comprehensively identify proteins that are necessary to activate or maintain G1 cell cycle arrest after cytokinesis failure and the induction of tetraploidy. Results from this screen, in combination with complementary bioinformatic and biochemical approaches, will illuminate the nature of the stresses associated with tetraploidy: this includes identifying how these stresses are sensed, how they feed into signaling cascades that activate p53, and how they are ultimately overcome by cancer cells. Strong gene hits from this screen will be examined to determine if they are similarly required to activate G1 arrest in response to other common cellular defects, and whether they are commonly lost or mutated in human cancers. Ultimately, the most interesting candidate genes will be tested for tumor suppressive activities in vitro and in vivo. Overall, the aims described in this proposal have strong potential to identify the cellular defects associated with tetraploidy, as well as to uncover novel regulatory mechanisms of p53. Moreover, this work may also lead to the identification of new pathways that can be targeted by chemotherapeutics to reinforce G1 arrest in abnormal cancer cells. Candidate Career Goals: My long-term career goal is to obtain a tenure-track faculty position at a leading academic institution and establish a lab that is at the forefront of unraveling the many mysteries of cell cycle progression. In particular, I have noticed a great divide in the approaches used by cell biologists and cancer biologists to understand both the causes and consequences of cancer: in my lab, I plan on bridging this gap by combining my pre-existing cell biological expertise with the new training opportunities in genome-wide screening, bioinformatics, and transformation assays described in this proposal. Ultimately, my aim is to blend these two fields in order to take a unique multifaceted experimental approach to probe the detailed mechanisms governing cell cycle progression. The K99/R00 award will provide the protected time I need for focused advanced training in order to achieve this career goal. I expect the mentored phase of this proposal, which includes completing the genome-wide screen and characterizing novel pathways that regulate p53, to take 1-2 years and result in at least one high quality publication. The following independent phase of the award will then permit me to further explore the activation and regulation of these signaling pathways, as well as to uncover new tumor suppressor pathways. Together, these data will be used to justify future studies proposed in an R01 grant application that I expect to submit at the beginning of the third year of the independent phase. Environment: The Department of Pediatric Oncology at the Dana-Farber Cancer Institute (DFCI) and Harvard Medial School has an internationally recognized research program that houses a number of expert researchers in the areas of cell proliferation, tumorigenesis, and cancer cell biology. I have assembled a stellar mentoring and advisory committee (Dr. David Pellman, Dr. William Kaelin, Dr. Ron Depinho, Dr. Matt Meyerson, and Dr. William Hahn) that will greatly benefit my research and training experience. I will meet with members of this committee informally as needed for specific scientific or experimental advice, and formally twice a year to discuss the general progress of my project, identify key future directions, and plan for my transition to independence. In addition, the Harvard Medical Area has all of the necessary physical resources required to for me to complete the proposed training and research studies, including facilities for FACS sorting, mass spectrometry, microarray analysis, and genome-wide screening.

描述（由申请人提供）：研究：四倍体细胞是细胞分裂失败的常见副产品，遗传不稳定，具有促进肿瘤发生的能力。因此，细胞具有p53依赖的肿瘤抑制机制，通过促进持久的G1细胞周期阻滞来限制这些细胞的进一步增殖。然而，与其他激活p53并促进G1阻滞的常见细胞损伤（如DNA损伤反应）不同，四倍体反应中控制G1阻滞的机制在很大程度上仍未被探索。该提案的主要目标是揭示细胞如何“感知”与四倍体相关的细胞变化，然后将该信息传递到p53途径以防止细胞周期进展。为了解决这个基本问题，我开发了一种新的全基因组RNAi筛选方法，以全面鉴定在细胞质分裂失败和诱导四倍体后激活或维持G1细胞周期停滞所必需的蛋白质。结合互补的生物信息学和生化方法，该筛选结果将阐明与四倍体相关的压力的本质：这包括确定这些压力是如何被感知的，它们是如何进入激活p53的信号级联的，以及它们最终是如何被癌细胞克服的。我们将检查来自该筛选的强基因命中，以确定它们是否同样需要激活G1抑制以响应其他常见的细胞缺陷，以及它们是否在人类癌症中通常丢失或突变。最终，最有趣的候选基因将在体外和体内进行肿瘤抑制活性测试。总的来说，本提案中描述的目标具有很强的潜力，可以识别与四倍体相关的细胞缺陷，并揭示p53的新调控机制。此外，这项工作还可能导致发现新的途径，这些途径可以被化疗药物靶向，以加强异常癌细胞中的G1阻滞。