Role of TOP2B in generating complex genomic rearrangements in human cancer

TOP2B 在人类癌症中产生复杂基因组重排的作用

• 批准号: 9437687
• 负责人: Sarah J Wheelan
• 金额: $ 33.62万
• 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: 2014-04-01 至 2019-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9437687
• 关键词: Adult; Androgen Receptor; Androgens; Architecture; Automobile Driving; Binding; Biological Markers; Biological Models; Cancer Biology; Cancer Etiology; Cells; Chromatin Loop; Chromosomal Rearrangement; Clinical Course of Disease; Complex; Computational Biology; Computing Methodologies; DNA Sequence Rearrangement; Data; Development; Diagnosis; Disease Progression; Enzymes; Event; Foundations; Functional disorder; Gene Expression; Generations; Genes; Genetic; Genetic Recombination; Genetic Transcription; Genome; Genomics; Goals; Human; Intercept; Intervention; Malignant Neoplasms; Malignant neoplasm of prostate; Measures; Mediating; Methods; Molecular; Molecular Conformation; Morbidity - disease rate; Oncogenic; Outcome; Pharmacology; Production; Prostate; Receptor Signaling; Recurrence; Reporting; Resolution; Risk stratification; Role; Site; Statistical Methods; Testing; Tissues; Topoisomerase II; United States; Work; base; cancer biomarkers; cancer initiation; cancer prevention; early onset; genome sequencing; innovation; men; mortality; neoplastic; prevent; programs; prostate cancer cell line; prostate cancer prevention; prostate cancer risk; public health relevance; repaired; tool development; transcription factor; tumor progression; whole genome

DESCRIPTION (provided by applicant): Although recent studies have shown the importance of complex genomic rearrangements in prostate cancer initiation and progression, the mechanisms that generate these rearrangements are unknown. Our long-term goal is to understand the causes and consequences of these complex rearrangements in prostate and other cancers. The objective here is to determine the mechanism by which multiple, coordinate, double strand breaks (DSB) likely involved in generating these complex rearrangements can form. Our central hypothesis is that initiation of androgen-induced transcriptional programs in neoplastic prostate cells involves the formation of highly complex topological loops that are mediated in part by topoisomerase II beta (TOP2B); dysfunction of this enzyme can produce multiple simultaneous breaks that can recombine to form complex genomic rear- rangements. We have formulated this hypothesis on the basis of our strong preliminary data showing andro- gen-induced, TOP2B-mediated DSB that are recombinogenic and arise near rearrangement breakpoints ob- served in human prostate cancers. The rationale for this work is that understanding these mechanisms can inform strategies to prevent formation of these rearrangements, potentially allowing cancer prevention and interception, and may also spur development of rearrangement-based biomarkers for prostate cancer risk stratification. We will test our hypothesis through three specific aims: 1) Determine the role of TOP2B in chromosomal conformational remodeling during initiation of androgen receptor (AR) mediated transcriptional programs. 2) Identify the role of TOP2B binding and catalytic activity in generating androgen-induced double strand breaks and recombination/rearrangement events. 3) Determine the relevance and utility of a TOP2B-related rearrangement signature in human prostate cancer. To facilitate these aims, we have innovated and/or established feasibility in our hands for: i) robust methods for genetic and pharmacologic inhibition of TOP2B; ii) well defined prostate cancer cell line model systems to study androgen receptor signaling; iii) identification o rearrangement breakpoints in human prostate cancers with low-pass paired-end sequencing; iv) methods for measuring TOP2B-mediated chromosomal looping interactions, gene expression changes, DSB, and recombination events; and iv) powerful statistical methods for assessing the spatial correlations of these TOP2B- related events with each other and with rearrangement breakpoints identified in human cancers. Using such correlations with data collected here and with publically available data, we will be able to assess whether a TOP2B/AR rearrangement signature has relevance to human prostate cancer rearrangements and whether it can have utility for prostate cancer risk stratification. The approach is innovative and highly significant because it uses powerful new experimental and computational methodologies to test an innovative hypothesis explaining the formation of highly complex, context-specific rearrangements observed in human prostate cancer. This understanding can ultimately inform approaches for prostate cancer prevention and interception.

描述（由申请人提供）：尽管最近的研究表明复杂的基因组重排在前列腺癌的发生和发展中的重要性，但产生这些重排的机制尚不清楚。我们的长期目标是了解前列腺和其他癌症中这些复杂重排的原因和后果。这里的目的是确定可能参与产生这些复杂重排的多个、协调的双链断裂（DSB）可以形成的机制。我们的中心假设是，肿瘤性前列腺细胞中雄激素诱导的转录程序的启动涉及部分由拓扑异构酶II β（TOP 2B）介导的高度复杂的拓扑环的形成;这种酶的功能障碍可以产生多个同时断裂，这些断裂可以重组形成复杂的基因组重排。我们基于我们强有力的初步数据制定了这一假设，这些数据显示雄激素诱导的、TOP 2B介导的DSB是重组原性的，并且在人前列腺癌中观察到的重排断点附近出现。这项工作的基本原理是，了解这些机制可以为预防这些重排形成的策略提供信息，可能允许癌症预防和拦截，并且还可能刺激基于重排的前列腺癌风险分层生物标志物的开发。我们将通过三个具体目标来验证我们的假设：1）确定TOP 2B在雄激素受体（AR）介导的转录程序启动期间染色体构象重塑中的作用。2)确定TOP 2B结合和催化活性在产生雄激素诱导的双链断裂和重组/重排事件中的作用。3)确定TOP 2B相关重排标记在人前列腺癌中的相关性和实用性。为了促进这些目标，我们已经在以下方面进行了创新和/或建立了可行性：i）用于TOP 2B的遗传和药理学抑制的稳健方法; ii）用于研究雄激素受体信号传导的明确定义的前列腺癌细胞系模型系统; iii）用低通配对末端测序鉴定人前列腺癌中的重排断裂点; iv）用于测量T0 P2B介导的染色体成环相互作用、基因表达变化、DSB和重组事件的方法;和iv）用于评估这些TOP 2B的空间相关性的强大统计方法-与人类癌症中鉴定的重排断裂点相关的事件。使用这种与这里收集的数据和临床可用数据的相关性，我们将能够评估TOP 2B/AR重排特征是否与人类前列腺癌重排相关，以及它是否可以用于前列腺癌风险分层。这种方法是创新的，非常重要的，因为它使用强大的新实验和计算方法来测试一个创新的假设，解释在人类前列腺癌中观察到的高度复杂的，上下文特异性重排的形成。这种理解最终可以为前列腺癌的预防和拦截提供信息。