Conserved coamplification event in HER2+ breast cancer increases metastasis

HER2 乳腺癌中保守的共扩增事件会增加转移

• 批准号: 10603730
• 负责人: Carson Dennis Broeker
• 金额: $ 4.77万
• 依托单位: MICHIGAN STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-09-29 至 2026-09-28
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10603730
• 关键词: 17q21; Address; Affect; Automobile Driving; Binding; Biological Assay; Breast Cancer Patient; Breast cancer metastasis; Candidate Disease Gene; Cause of Death; Cell Line; Cell Survival; Cells; Chromosome 17; Chromosomes; Clinical; Co-Immunoprecipitations; Collagen; Collagen Gene; Collagen Type I; Data; Dependence; Distant; ERBB2 gene; Epidermal Growth Factor Receptor; Epithelial Cells; Evaluation; Event; Exhibits; Extracellular Matrix; Extravasation; Failure; Family; Future; Gene Dosage; Gene Expression; Gene Expression Profiling; Gene set enrichment analysis; Genes; Genetic; Genomics; Goals; Human; Human Cell Line; Human Characteristics; Human Chromosomes; Immunocompromised Host; Immunohistochemistry; Immunoprecipitation; In Situ Nick-End Labeling; Individual; Injections; Integrins; Knock-out; Knowledge; Literature; MAP Kinase Gene; MEKs; Malignant Neoplasms; Measures; Mediating; Methods; Modeling; Molecular; Monoclonal Antibodies; Mouse Cell Line; Mouse Mammary Tumor Virus; Mus; Neoplasm Metastasis; Oncogenic; Outcome; Paper; Pathway interactions; Patients; Phenotype; Preclinical Testing; Primary Neoplasm; Proliferating; Protein Isoforms; Proteins; Public Health; Ras/Raf; Rattus; Receptor Protein-Tyrosine Kinases; Research; Role; Sampling; Signal Pathway; Signal Transduction; Signal Transduction Pathway; Stains; Testing; The Cancer Genome Atlas; Transgenic Mice; Tyrosine Kinase Inhibitor; Up-Regulation; Woman; arm; cancer diagnosis; cell motility; chemotherapy; driving force; experimental study; extracellular; genome sequencing; genomic data; improved; in vivo; knock-down; malignant breast neoplasm; migration; mortality; mouse model; overexpression; prognosis biomarker; prognostic indicator; prohibitin; promoter; protein protein interaction; relapse risk; targeted treatment; transcriptomics; tumor; tumor microenvironment; whole genome

PROJECT SUMMARY Breast cancer is the most common cancer diagnosed among women and is estimated to be the leading cause of death for women worldwide. Approximately one fifth of breast cancer patients’ tumors overexpress the human epidermal growth factor receptor 2 (HER2) protein; this is the result of an amplification event on the long arm of human chromosome 17, leading to high copy number gains of the HER2/Neu gene (ERBB2). Metastatic HER2+ breast cancer is more aggressive than other subtypes of breast cancer, responds poorly to general chemotherapy, and is invariably fatal. Lack of understanding of the molecular mechanisms that underpin the metastatic cascade leads to limited therapy options and poor clinical outcomes. To study the mechanisms of metastasis in HER2+ breast cancer, we utilize a transgenic mouse model which overexpresses Neu, the rat isoform of HER2, under control of the mouse mammary tumor virus (MMTV) promoter, henceforth known as MMTV-Neu. Interestingly, our recent paper describing whole genome sequencing (WGS) of MMTV-Neu primary tumors revealed a coamplification event centered on mouse chromosome 11qD, near Erbb2, in a majority of samples. Comparing these results to human genomic data through The Cancer Genome Atlas (TCGA) reveals an analogous amplification event on the highly syntenic human chromosome 17q21.33 near, but separate from, the ERBB2 amplicon. This secondary amplicon was found to be present in 25% of HER2+ patients, 9% of all breast cancers, and contains a number of candidate genes that putatively mediate metastasis. Preliminary data addresses the potential for these candidate genes in mediating metastasis, but the molecular mechanisms for how this occurs remains unknown. The central hypothesis of this proposal is that upregulation of three genes in this amplicon, collagen type 1 alpha 1 chain (Col1A1), chondroadherin (CHAD), and prohibitin (PHB), increases metastasis through alterations to the tumor microenvironment and oncogenic signaling pathways. This hypothesis will be evaluated using three independent aims that will collectively identify key events and dependencies in the HER2+ metastatic cascade. Aim 1 identifies the stage of metastasis affected by the 17q21.33 amplicon by knockout/knockdown and overexpression of the three candidate genes in HER2+/Neu overexpressing cell lines injected into syngeneic mice. Aim 2 utilizes transcriptomic differences between tumors, immunohistochemistry (IHC), and co-immunoprecipitation (Co-IP) to determine signaling network differences between tumors +/- for candidate genes and spatial expression of genes within the tumor. Aim 3 determines what genes in the amplicon are necessary or sufficient to increase metastasis by overexpressing candidate genes alone or in tandem and measuring effects on migration and metastasis. The long-term objectives and broad goals of this hypothesis driven proposal are to provide an increased understanding of why some breast cancers become metastatic, ultimately to improve patient clinical outcomes.

项目摘要 乳腺癌是女性中最常见的癌症，估计是女性中最常见的癌症。 全球女性的死亡原因。大约五分之一的乳腺癌患者的肿瘤过度表达 人表皮生长因子受体2（HER 2）蛋白;这是长 人17号染色体臂，导致HER 2/Neu基因（ERBB 2）的高拷贝数增加。转移性 HER 2+乳腺癌比其他乳腺癌亚型更具侵袭性，对一般化疗反应较差。 化疗，并且总是致命的。缺乏对支持这些疾病的分子机制的理解， 转移级联导致有限的治疗选择和差的临床结果。为了研究 在HER 2+乳腺癌的转移中，我们利用过表达Neu的转基因小鼠模型， 在小鼠乳腺肿瘤病毒（MMTV）启动子的控制下，HER 2的同种型，此后称为 MMTV-Neu。有趣的是，我们最近的论文描述了MMTV-Neu原发性 肿瘤显示了一个共扩增事件，集中在小鼠染色体11 qD，靠近Erbb 2，在大多数肿瘤中， 样品通过癌症基因组图谱（TCGA）将这些结果与人类基因组数据进行比较， 在高度同线的人类染色体17q21.33上的类似扩增事件，靠近，但与， ERBB 2扩增子。发现这种二级扩增子存在于25%的HER 2+患者中， 乳腺癌，并含有大量的候选基因，puronectin介导的转移。初步数据 解决了这些候选基因在介导转移中的潜力，但这些候选基因的分子机制尚未阐明。 这是如何发生的仍不清楚。这个提议的中心假设是三个基因的上调 在该扩增子中，1型胶原α 1链（Col 1A 1）、软骨粘附素（CHAD）和抑制素（PHB）， 通过改变肿瘤微环境和致癌信号通路增加转移。这 假设将使用三个独立的目标进行评估，这些目标将共同确定关键事件， HER 2+转移级联中的依赖性。目的1确定受肿瘤转移影响的阶段， 通过在HER 2 +/Neu中敲除/敲低和过表达三个候选基因的17q21.33扩增子 过表达的细胞系注射到同基因小鼠中。目的2利用肿瘤之间的转录组学差异， 免疫组化（IHC）和免疫共沉淀（Co-IP）以确定信号网络差异 候选基因和肿瘤内基因的空间表达的肿瘤之间+/-。目标3确定 扩增子中的哪些基因是通过过度表达候选基因而增加转移所必需或足够的 单独或串联的基因，并测量对迁移和转移的影响。长期目标和 这一假设驱动的建议的广泛目标是提供更多的理解，为什么一些乳房 癌症转移，最终改善患者的临床结果。