Tracing the origins of chromosomal translocations in prostate cancer

追踪前列腺癌染色体易位的起源

• 批准号: 9045579
• 负责人: Ram Shankar Mani
• 金额: $ 24.9万
• 依托单位: UT SOUTHWESTERN MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-08-15 至 2018-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9045579
• 关键词: 5' Untranslated Regions; Affect; Air; Androgen Receptor; Androgens; Antibodies; Architecture; Binding; Biological Assay; Carcinoma; Cell Cycle Progression; Cell Line; Cells; ChIP-seq; Chromatin Interaction Analysis by Paired-End Tag Sequencing; Chromosomal translocation; Coculture Techniques; DNA; DNA Double Strand Break; Data; Data Set; Development; ERG gene; ETS Family Gene; Enzyme Activation; Etiology; Future; Gene Expression Profiling; Gene Expression Regulation; Gene Fusion; Genes; Genome; Genomics; Goals; Hematologic Neoplasms; Human; Human Genome; Inflammation; LNCaP; Lead; Lentivirus Vector; Light; Link; Malignant Neoplasms; Malignant neoplasm of prostate; Mediating; Mentors; Methodology; Modeling; Mus; Mutate; Mutation; Noise; Oncogene Activation; Operative Surgical Procedures; PSA screening; Pathway interactions; Patients; Phase; Phosphorylation; Prevalence; Prostate; Publications; Recurrence; Regulation; Resources; Role; Signal Transduction; Soft Tissue Neoplasms; Specificity; Suggestion; TMPRSS2 gene; Technology; Testing; Tissue Microarray; Tissues; Up-Regulation; abstracting; activation-induced cytidine deaminase; base; career; cell type; cohort; genome sequencing; genome-wide; improved; in vivo; leukemia/lymphoma; macrophage; next generation sequencing; novel; overexpression; p65; research study; sarcoma; skills; transcriptome sequencing; tumor progression; whole genome

Abstract Chromosomal translocations are a hallmark of cancer progression. These translocations often result in gene fusions, a common mechanism for oncogene activation. Until recently, recurrent gene fusions were predominantly associated with hematological malignancies (leukemias and lymphomas) and soft tissue tumors (sarcomas), but were rarely linked to common epithelial carcinomas. This view changed with the discovery of recurrent gene fusions involving ETS family genes in prostate cancer. Among the ETS family gene fusions, the TMPRSS2-ERG fusions involving the 5’untranslated region of androgen-regulated gene TMPRSS2 with the ERG gene are the most common and found in approximately 50% of prostate cancers. The development of next generation sequencing based approaches like RNA-Seq and paired-end whole-genome sequencing have accelerated the discoveries of gene fusions in prostate cancer. However, the mechanisms underlying the formation and cell type specificities of chromosomal translocations are far from clear. Our proposal aims to bridge the gap between the rapid discovery of chromosomal translocations and our limited understanding of the mechanisms leading to their formation. In our recent study, we demonstrate that androgen signaling induces chromosomal proximity between TMPRSS2 and ERG loci, and facilitates the formation of the TMPRSS2-ERG gene fusion when subjected to an agent that causes DNA double strand breaks. These results provide a conceptual framework for the genesis of gene fusions in human prostate cancer. In specific aim 1, we propose to employ next-generation sequencing to identify genome-wide chromosomal interactions mediated by androgen signaling. The mentor’s expertise in throughput technologies will help the candidate acquire the necessary skill-set to accomplish aim 1. Interestingly, we identified novel recurrent mutations in the androgen receptor AR collaborating factor FOXA1, which is mutated in 5 of 147 (3.4%) prostate cancers. Preliminary functional studies on one representative mutation revealed that mutated FOXA1 disrupts androgen signaling and increases proliferation. In specific aim 2, we propose to study the effect of FOXA1 mutations in regulating AR signaling and interactome. Aim 2, a logical extension of aim 1 will be pursued during the independent phase (R00). Accomplishment of these two aims will provide us with a comprehensive understanding of the three dimensional genomic architecture of prostatic cells, how AR regulates this architecture, the influence mutations in AR collaborating factors, and importantly how this impacts the formation of gene fusions. While spatial proximity is necessary for chromosomal translocations, it is not sufficient. DNA breaks synergize with spatial proximity to fuel chromosomal translocations. In specific aim 3, we will study the role of inflammation mediated activation of NF-κB pathway in the formation of DNA breaks and ETS gene fusions in prostate cancer. Successful completion of the aims outlined in this proposal will improve our understanding of the origins of chromosomal translocations in prostate cancer, may have broader implications for understanding and treating cancer and may provide suggestions as to the general etiology of human prostate cancer. These projects have been conceived based on my original ideas. Dr. Chinnaiyan has extended his full support towards my career goals and has encouraged me to take these projects to my independent lab in the future.

抽象的 染色体易位是癌症进展的标志，这些易位通常会导致基因突变。 融合是癌基因激活的常见机制，直到最近，复发性基因融合仍然存在。 主要与血液恶性肿瘤（白血病和淋巴瘤）和软组织肿瘤相关 （肉瘤），但很少与常见的上皮癌联系起来，这种观点随着肉瘤的发现而改变。 前列腺癌中涉及 ETS 家族基因的复发性基因融合。 TMPRSS2-ERG 将雄激素调节基因 TMPRSS2 的 5’非翻译区与 ERG 基因是最常见的，在大约 50% 的前列腺癌中都有发现。 基于下一代测序的方法，如 RNA-Seq 和双端全基因组测序， 加速了前列腺癌基因融合的发现，然而，其背后的机制。 染色体易位的形成和细胞类型特异性尚不清楚。 弥合染色体易位的快速发现与我们对染色体易位的有限理解之间的差距 在我们最近的研究中，我们证明了雄激素信号传导。 诱导 TMPRSS2 和 ERG 位点之间的染色体接近，并促进形成 当受到导致 DNA 双链断裂的试剂时，TMPRSS2-ERG 基因融合。 具体而言，结果为人类前列腺癌中基因融合的发生提供了概念框架。 目标 1，我们建议采用下一代测序来识别全基因组染色体相互作用 由雄激素信号传导介导的导师在吞吐量技术方面的专业知识将帮助候选人。 获得实现目标 1 所需的技能。暗示，我们在 雄激素受体 AR 协同因子 FOXA1，在 147 例前列腺癌中的 5 例 (3.4%) 中发生突变。 对一种代表性突变的初步功能研究表明，突变的 FOXA1 会破坏雄激素 在具体目标 2 中，我们建议研究 FOXA1 突变对细胞的影响。 目标 2 是目标 1 的逻辑延伸。 独立阶段（R00）的实现将为我们提供全面的支持。 了解前列腺细胞的三维基因组结构，AR 如何调节它 架构、AR 协作因素的影响突变，以及重要的是这如何影响 虽然空间接近对于染色体易位是必要的，但事实并非如此。 在具体目标 3 中，DNA 断裂与空间邻近性协同作用。 我们将研究炎症介导的 NF-κB 通路激活在 DNA 断裂形成中的作用 前列腺癌中的 ETS 基因融合将成功完成本提案中概述的目标。 提高我们对前列腺癌染色体易位起源的理解，可能具有更广泛的意义 对理解和治疗癌症的影响，并可能为癌症的一般病因学提供建议 这些项目是根据 Chinnaiyan 博士的原创想法构思的。 他对我的职业目标给予了全力支持，并鼓励我将这些项目付诸实践。 未来有独立实验室。