Determine the Functional Role Dub3 in Breast Cancer Progression and Metastasis

确定 Dub3 在乳腺癌进展和转移中的功能作用

• 批准号: 9257365
• 负责人: Binhua P Zhou
• 金额: $ 34.47万
• 依托单位: UNIVERSITY OF KENTUCKY
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-04-01 至 2020-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9257365
• 关键词: Address; Brain; Breast; Breast Cancer Cell; Breast cancer metastasis; Cell Line; Cells; Chromatin; Clinical; Coupled; Crystallization; Data; Deubiquitination; Development; Diagnosis; Disease; Distant Metastasis; Drosophila genus; E-Cadherin; ERG gene; Embryonic Development; Environment; Enzymes; Epithelial; Event; Exposure to; Genes; Goals; Growth; Human; Inflammatory; Intrinsic factor; Investigation; KDM1A gene; Knock-out; Knowledge; Libraries; Location; Lung; MCF7 cell; Malignant Neoplasms; Mammary Neoplasms; Mass Spectrum Analysis; Mesenchymal; Metabolic; Metastatic breast cancer; Modeling; Molecular; Mus; Neoplasm Metastasis; Oncologist; Pathologist; Pharmaceutical Preparations; Phase; Phenotype; Phosphoric Monoester Hydrolases; Phosphorylation; Phosphotransferases; Prognostic Marker; Property; Proteins; Public Health; Reagent; Recording of previous events; Recruitment Activity; Recurrence; Regulation; Research; Role; Sampling; Signal Transduction; Site; Small Interfering RNA; Snails; Specimen; Stromal Neoplasm; Structural Biologist; Structure; T47D; Talents; Testing; Therapeutic; Tissues; Treatment Efficacy; Tumor Cell Invasion; Ubiquitination; Validation; Wound Healing; Xenograft procedure; aerobic glycolysis; base; beta-Transducin Repeat-Containing Proteins; cancer stem cell; cancer therapy; cell growth regulation; cell motility; cytokine; diagnostic biomarker; experimental study; functional plasticity; gastrulation; glycogen synthase kinase 3 beta; in vivo; inhibitor/antagonist; innovation; knock-down; loss of function; macrophage; malignant breast neoplasm; multidisciplinary; neoplastic cell; new therapeutic target; novel strategies; outcome forecast; overexpression; prevent; prognostic; programs; promoter; public health relevance; screening; success; targeted biomarker; targeted treatment; therapy resistant; tumor; tumor microenvironment; tumor progression; ubiquitin-protein ligase; virtual; young woman

 DESCRIPTION (provided by applicant): Basal-like breast cancer (BLBC) presents with an aggressive clinical history, development of recurrence, distant metastasis, shorter survival, and usually occurs in young women. BLBC has an activated epithelial-mesenchymal transition (EMT) program, which provides cells with the increased phenotypic and cellular plasticity required during embryonic development, tissue remodeling, wound healing and metastasis. Our long-term goal is to discover the molecular circuitry that governs the functional plasticity of BLBC cells in metastasis and to identify molecules that may serve as druggable targets for treating this deadly disease. In the last nine years, we have systematically studied the function of Snail and the molecular mechanism by which Snail represses E-cadherin expression in BLBC. Our studies clearly indicate that Snail levels are regulated predominantly through protein ubiquitination. High levels of Snail, due to protein stabilization, contribute significantly to the increased invasion, therapeutic resistance, CSC-like properties, and tumor recurrence. However, the mechanism by which Snail escapes ubiquitination and degradation remains unknown; uncovering this mechanism is crucially important for the development of novel approaches to treat BLBC. Recently, we discovered that Dub3 is a bona fide deubiquitinase of Snail and contributes to Snail stabilization in breast cancer. Dub3 is evolutionarily conserved from Drosophila to humans. Dub3-knockout downregulated Snail and disrupted gastrulation (an event that requires EMT) in Drosophila. Elevated expression of Dub3 correlates unequivocally with Snail expression in BLBC samples and cell lines. Overexpression of Dub3 in luminal breast tumor MCF7 and T47D cell lines, which contain no detectable endogenous Dub3 and Snail, induces transformation to a basal-like phenotype; whereas, Dub3-knockdown downregulates Snail and suppresses cell migration. Intriguingly, Dub3 was an early response gene that appeared after exposure to inflammatory cytokines. We hypothesize that Dub3 is the long-sought "missing molecule" that regulates cellular plasticity by controlling the level of Snail durig EMT and metastasis. The objective of this proposal is to characterize the function and regulation of the Dub3-Snail axis and explore the clinical value of Dub3 as a prognostic biomarker and a druggable target for treating metastatic breast cancer. Guided by strong preliminary data, we will test this hypothesis by pursuing three specific aims: (1) to delineate th molecular mechanism by which Dub3 controls EMT; (2) to determine the function and regulation of Dub3 in breast cancer; and (3) to define the function and therapeutic efficacy of Dub3 in vivo. Our proposal is innovative and significant, because it will not only uncover a new paradigm that significantly increases our understanding of the regulation of cellular plasticity during tumor progression and metastasis but also leads to the development of specific Dub3 inhibitors for treating metastatic breast cancer.

 描述（由申请人提供）：基底样乳腺癌（BLBC）具有侵袭性临床病史、复发、远处转移、生存期较短，通常发生于年轻女性。 BLBC 具有激活的上皮间质转化 (EMT) 程序，可为细胞提供胚胎发育、组织重塑、伤口愈合和转移过程中所需的增强表型和细胞可塑性。我们的长期目标是发现控制 BLBC 细胞在转移中功能可塑性的分子回路，并确定可作为治疗这种致命疾病的药物靶点的分子。近9年来，我们系统研究了Snail的功能以及Snail抑制BLBC中E-cadherin表达的分子机制。我们的研究清楚地表明，Snail 水平主要通过蛋白质泛素化来调节。由于蛋白质稳定，高水平的蜗牛对 增加侵袭、治疗耐药性、CSC 样特性和肿瘤复发。然而，Snail 逃避泛素化和降解的机制仍然未知。揭示这一机制对于开发治疗 BLBC 的新方法至关重要。最近，我们发现 Dub3 是 Snail 真正的去泛素酶，有助于 Snail 在乳腺癌中的稳定。 Dub3 从果蝇到人类在进化上都是保守的。在果蝇中，Dub3 敲除下调了 Snail 的表达并扰乱了原肠胚形成（需要 EMT 的事件）。 Dub3 表达升高与 BLBC 样本和细胞系中的 Snail 表达明确相关。 Dub3 在管腔乳腺肿瘤 MCF7 和 T47D 细胞系中过度表达（不含可检测到的内源性 Dub3 和 Snail），会诱导向基底样表型的转化；而 Dub3 敲低则下调 Snail 并抑制细胞迁移。有趣的是，Dub3 是一种早期反应基因，在暴露于炎症细胞因子后出现。我们假设 Dub3 是长期寻找的“缺失分子”，它通过控制 EMT 和转移过程中 Snail 的水平来调节细胞可塑性。该提案的目的是表征 Dub3-Snail 轴的功能和调节，并探索 Dub3 作为预后生物标志物和治疗转移性乳腺癌的药物靶点的临床价值。在强有力的初步数据的指导下，我们将通过三个具体目标来检验这一假设：（1）描绘Dub3控制EMT的分子机制； (2)确定Dub3在乳腺癌中的功能和调控； (3)明确Dub3在体内的功能和治疗效果。我们的提议具有创新性和意义，因为它不仅揭示了一个新的范例，显着增加了我们对肿瘤进展和转移过程中细胞可塑性调节的理解，而且还导致了用于治疗转移性乳腺癌的特异性 Dub3 抑制剂的开发。