RNA Binding Proteins in Cancer

癌症中的 RNA 结合蛋白

• 批准号: 8018162
• 负责人: Shrikant Anant
• 金额: $ 30.19万
• 依托单位: UNIVERSITY OF KANSAS MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-04-01 至 2014-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8018162
• 关键词: 3' Untranslated Regions; Affinity; Anchorage-Independent Growth; Apoptosis; Behavior; Binding; Binding Sites; C-terminal; Cancer Model; Cause of Death; Cell Death; Cell Survival; Cells; Colon Carcinoma; Consensus; Deletion Mutation; Disease; Elements; Epidermal Growth Factor; Epithelial Cells; Gene Expression; Gene Expression Regulation; Genetic Translation; Glycine; Goals; Growth; Health; Interleukin-8; Intestines; Lead; Malignant Neoplasms; Manuscripts; Mediating; Messenger RNA; Methods; MicroRNAs; Mitosis; Mitotic; Modification; Mus; Mutagenesis; N-terminal; Normal Cell; Nude Mice; Pathway interactions; Phenotype; Phosphorylation; Post-Transcriptional Regulation; Process; Promoter Regions; Protein Binding; Protein Overexpression; Proteins; Proto-Oncogenes; Publishing; RNA Binding; RNA Recognition Motif; RNA Sequences; RNA Stability; RNA-Binding Proteins; Ribonucleoproteins; Ribosomes; Role; Serine; Signal Pathway; Site; Threonine; Transcript; Transcriptional Activation; Translations; Tyrosine Phosphorylation Site; Ubiquitination; United States; Vascular Endothelial Growth Factors; Work; Xenograft procedure; base; cancer cell; cyclooxygenase 2; deletion analysis; human FRAP1 protein; mRNA Decay; mRNA Stability; mTOR protein; mutant; neoplastic cell; notch protein; novel; overexpression; promoter; research study; tumor; tumor xenograft; tumorigenesis

DESCRIPTION (provided by applicant): The broad goal of the project is to understand the mechanisms by which RNA binding protein RBM3 regulates gene expression at the posttranscriptional level of mRNA stability and translation in cancer cells. We have identified that overexpression of the protein causes a normal cell to undergo a transformed phenotype resulting in the cells forming tumors in immunocompromized mice. On the other hand, knockdown of RBM3 expression results in cell death due to mitotic catastrophe. RBM3 interacts with HuR and hnRNP A1, and with AU-RNA sequences to enhance mRNA stability and translation of AU-rich transcripts such as COX-2, VEGF and IL-8. In addition, RBM3 overexpression increases the activation of the mammalian target of rapamycin protein in a Notch dependent mechanism. We have also identified microRNAs regulated upon RBM3 overexpression, including downregulating one that inhibits its own expression. Our studies also suggest that RBM3 is regulated at the posttranslational levels of phosphorylation, ubiquitination and SUMOylation. Based on these observations, we propose three specific aims. In Aim 1, we will determine the mechanism by which RNA binding protein RBM3 regulates gene expression. Here, we will identify the RNA sequences that interact with RBM3. In addition, we will determine the sequenced in COX-2 3'UTR that are required for RBM3-mediated COX-2 mRNA stability and translation. We will also identify the role of HuR and hnRNP-A1 in the process. In Aim 2, we will determine the residues in RBM3 that undergo phosphorylation, ubiquitination and SUMOylation by mutagenesis. We will also determine the effect of the mutants on mRNA stability and translation. In Aim 3, we propose to determine the mechanisms by which RBM3 induces tumorigenesis. We will use an xenograft cancer model to determine the role of mTOR and Notch pathway in RBM3 mediated tumorigenesis. Also, the role of microRNAs in the tumorigenesis will be determined. Completion of these experiments should give us a better understanding of how the RNA binding protein RBM3 functions in normal epithelial cells, and whether changes in the RBM3 expression that is observed in tumor cells is responsible for tumor behavior. PUBLIC HEALTH RELEVANCE: Cancer is the leading cause of death in the United States. Understanding how the normal cell progresses to a cancer will aid in our developing novel therapies for this dreaded disease. We have identified a protein, RBM3 whose expression is increased in cancer cells. Overexpressing RBM3 protein causes a normal cell to become transformed into a cancer cell. Our current proposal deals with identifying mechanisms by which RBM3 expression is regulated, and also how RBM3 induces tumorigenesis. We expect that the work will lead to a better understanding of the tumorigenesis process which should subsequently lead to novel methods to stop or slow down tumorigenesis.

描述（由申请人提供）：该项目的广泛目标是了解RNA结合蛋白RBM3在mRNA稳定性的转录后水平和癌细胞转化的基因表达的机制。我们已经确定，蛋白质的过表达导致正常细胞发生转化的表型，从而导致在免疫功能低下的小鼠中形成肿瘤的细胞。另一方面，RBM3表达的敲低导致因有丝分裂灾难引起的细胞死亡。 RBM3与HUR和HNRNP A1相互作用，并与Au-RNA序列相互作用，以增强富含Au的转录本（例如COX-2，VEGF和IL-8）的mRNA稳定性和翻译。另外，RBM3的过表达增加了雷帕霉素蛋白在凹槽依赖机制中的激活。我们还确定了对RBM3过表达调节的microRNA，包括下调抑制其自身表达的microRNA。我们的研究还表明，RBM3受到磷酸化，泛素化和Sumoylation的翻译后水平的调节。基于这些观察结果，我们提出了三个具体目标。在AIM 1中，我们将确定RNA结合蛋白RBM3调节基因表达的机制。在这里，我们将确定与RBM3相互作用的RNA序列。此外，我们将确定RBM3介导的COX-2 mRNA稳定性和翻译所需的COX-2 3'UTR测序。我们还将确定HUR和HNRNP-A1在此过程中的作用。在AIM 2中，我们将确定RBM3中通过诱变经历磷酸化，泛素化和Sumoylation的残基。我们还将确定突变体对mRNA稳定性和翻译的影响。在AIM 3中，我们建议确定RBM3诱导肿瘤发生的机制。我们将使用异种移植癌模型来确定MTOR和Notch途径在RBM3介导的肿瘤发生中的作用。同样，将确定microRNA在肿瘤发生中的作用。这些实验的完成应使我们更好地了解正常上皮细胞中RNA结合蛋白RBM3的功能，以及在肿瘤细胞中观察到的RBM3表达的变化是否导致肿瘤行为。公共卫生相关性：癌症是美国死亡的主要原因。了解正常细胞如何发展为癌症将有助于我们为这种可怕疾病的新型疗法发展。我们已经确定了一种蛋白质，RBM3，其表达在癌细胞中的表达增加。过表达的RBM3蛋白会导致正常细胞转化为癌细胞。我们当前的建议涉及识别RBM3表达的机制，以及RBM3如何诱导肿瘤发生。我们预计这项工作将导致对肿瘤发生过程的更好理解，这应随后导致停止或减慢肿瘤发生的新方法。