The Role of miRNAs in Epithelial-Mesenchymal Transition and Metastasis

miRNA 在上皮-间质转化和转移中的作用

• 批准号: 8264374
• 负责人: Yibin Kang
• 金额: $ 31.92万
• 依托单位: PRINCETON UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-04-01 至 2015-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8264374
• 关键词: Animal Model; Animals; Biochemical; Biological Assay; Biological Models; Breast Cancer Cell; Cancer cell line; Candidate Disease Gene; Cell Line; Cessation of life; Complex; Data; Disseminated Malignant Neoplasm; Distant; E-Cadherin; Ectopic Expression; Engineering; Epithelial; Epithelial Cells; Family; Gene Expression Profiling; Gene Targeting; Genes; Genetic; Genomics; In Vitro; Invaded; Laboratories; Lead; Lesion; Malignant Epithelial Cell; Malignant Neoplasms; Mammary Neoplasms; Mammary gland; Mass Spectrum Analysis; Mediating; Mesenchymal; Metastatic to; Methods; Methyl-CpG-Binding Protein 2; MicroRNAs; Molecular; Mouse Mammary Tumor Virus; Mus; Neoplasm Metastasis; New Agents; Oncogenes; Organ; Pathologic Processes; Phenotype; Physiological; Physiology; Play; Prevention; Primary Neoplasm; Process; Proteomics; Regulator Genes; Research; Role; Site; Staging; Testing; Therapeutic; Tissues; Transgenic Mice; Validation; Xenograft procedure; epithelial to mesenchymal transition; gene function; improved; in vivo; in vivo Model; inhibitor/antagonist; insight; interdisciplinary approach; interest; malignant breast neoplasm; migration; mouse model; neoplastic cell; novel; overexpression; public health relevance; research study; tumor; tumor progression; tumorigenesis

DESCRIPTION (provided by applicant): MicroRNAs (miRNAs) have been increasingly recognized to play important roles in normal physiology and in pathological processes, including cancer. We recently identified the miR-200 family and the miR-194/192 cluster of miRNAs as negative regulators of epithelial-mesenchymal transition (EMT), which is thought to be the critical initiating step of cancer metastasis. These miRNAs maintain the epithelial cell phenotype and inhibit EMT by repressing the expression of transcriptional inhibitors of E-cadherin, including ZEB1/ZEB2 and MeCP2. Overexpression of these miRNAs inhibits TGF¿-induced EMT in normal mammary epithelial cells. Furthermore, ectopic expression of the EMT-related miRNAs in invasive breast tumor cells induces mesenchymal-epithelial transition (MET), the reverse process of EMT, with significant reduction of migration and invasion. Surprisingly, we also found that elevated miR-200 expression is correlated with increased ability of tumor cells to generate macroscopic lesions at secondary metastasis sites. These data in aggregate imply that there is a stage-specific role of these miRNAs in metastasis. Decreased miRNA expression in the primary tumor may stimulate EMT and subsequent dissemination of tumor cells, whereas increased miRNA expression will lead to MET and colonization of distant organs. As potentially new agents for anti-metastasis therapeutics, the functional role and molecular mechanism of these miRNAs in different stages of cancer progression require further characterization. We hypothesize that these miRNAs are critical master regulators of the transition between the epithelial and mesenchymal states of tumor cells and play important roles in both the initial invasion of primary tumors as well as metastatic colonization of secondary target organs. We will use a comprehensive approach to study the molecular mechanism of miRNA-mediated EMT and cancer metastasis, taking advantage of in vitro and in vivo models as well as genomic and proteomic research platforms available in our laboratory. To study the potential biphasic role of these miRNAs in metastasis, we will employ orthotopic and experimental metastasis assays. We will overexpress the miRNAs and modulate their downstream genes of interest in various mouse and human breast cancer cell lines and utilize in vivo animal models to investigate stage-specific effects on breast cancer metastasis (Aim 2). We will use combined analysis of gene expression profiling and mass spectrometry to identify novel target genes of EMT-related miRNAs and test the functional importance of these genes in EMT and metastasis using well-established in vitro and in vivo assays (Aim 2). Finally, we will evaluate the importance of EMT-related miRNAs in mammary gland function and mammary tumor progression using transgenic mouse models. We will generate MMTV transgenic mice for these miRNAs and test the role of these miRNAs in breast cancer progression in tumor-prone animals that overexpress the oncogene Neu or PyMT in their mammary tissue (Aim 3). Through these experiments, we will reveal the potential stage-specific roles and functional mechanisms for EMT-related miRNAs in cancer metastasis and provide important novel insights for improving the prevention and treatment of metastatic cancer. PUBLIC HEALTH RELEVANCE: Over 90% of cancer related deaths are due to the metastatic spread of primary tumor cells to distant vital organs. Epithelial-mesenchymal transition (EMT) and the reverse process, MET, have been postulated to be important processes for tumor cells to gain the ability to migrate and invade into their surrounding tissue and to regain their epithelial phenotype to facilitate colonization once they reach the target organs. This study will investigate how microRNAs, a novel class of genetic regulators, regulate EMT and will provide some of the best evidence to date as to whether EMT can promote early dissemination of tumor cells while MET may be essential for efficient colonization of distant target organs.

描述（由申请人提供）： 人们越来越认识到 MicroRNA (miRNA) 在正常生理学和病理过程（包括癌症）中发挥重要作用，我们最近将 miR-200 家族和 miR-194/192 miRNA 簇鉴定为阴性。上皮间质转化 (EMT) 的调节因子，被认为是癌症转移的关键起始步骤。通过抑制 E-钙粘蛋白转录抑制剂（包括 ZEB1/ZEB2 和 MeCP2）的表达来抑制 EMT，这些 miRNA 的过度表达会抑制 TGF¿此外，在侵袭性乳腺肿瘤细胞中，EMT 相关 miRNA 的异位表达会诱导间充质上皮转化（MET），这是 EMT 的逆过程，令人惊讶的是，我们发现迁移和侵袭显着减少。还发现，miR-200 表达升高与肿瘤细胞在继发性转移部位产生肉眼可见病变的能力增强相关，这些数据总的来说表明存在阶段特异性。这些 miRNA 在转移中的作用。原发肿瘤中 miRNA 表达的减少可能会刺激 EMT 和随后肿瘤细胞的扩散，而 miRNA 表达的增加将导致 MET 和远处器官的定植。这些 miRNA 在癌症进展的不同阶段中的作用和分子机制需要进一步表征，我们发现这些 miRNA 是肿瘤细胞上皮状态和间质状态之间转变的关键主调节因子。我们将利用体外和体内的综合方法来研究 miRNA 介导的 EMT 和癌症转移的分子机制。为了研究这些 miRNA 在转移中的潜在双相作用，我们将采用原位和实验转移测定法，我们将过度表达 miRNA 并调节它们。我们将利用基因表达谱和质谱的联合分析来确定新的靶标，并利用体内动物模型来研究对乳腺癌转移的阶段特异性影响（目标 2）。我们研究了 EMT 相关 miRNA 的基因，并使用成熟的体外和体内试验测试这些基因在 EMT 和转移中的功能重要性（目标 2）。使用转基因小鼠模型研究乳腺功能和乳腺肿瘤进展我们将针对这些 miRNA 生成 MMTV 转基因小鼠，并在乳腺组织中过度表达癌基因 Neu 或 PyMT 的易患肿瘤动物中测试这些 miRNA 在乳腺癌进展中的作用（Aim）。 3）通过这些实验，我们将揭示EMT相关miRNA在癌症转移中的潜在阶段特异性作用和功能机制，并为改善转移的预防和治疗提供重要的新见解。癌症。 公共健康相关性：超过 90% 的癌症相关死亡是由于原发肿瘤细胞转移至远处重要器官所致，而上皮间质转化 (EMT) 和相反的过程 MET 被认为是肿瘤细胞的重要过程。获得迁移和侵入周围组织的能力，并恢复其上皮表型，以便在到达目标器官后促进定殖。这项研究将如何研究 microRNA（一类新型遗传基因）。监管机构负责调节 EMT，并将提供迄今为止最好的一些证据，证明 EMT 是否可以促进肿瘤细胞的早期传播，而 MET 可能对于远处靶器官的有效定植至关重要。