Translational control of EMT by the CELF1 RNA Binding Protein

CELF1 RNA 结合蛋白对 EMT 的翻译控制

• 批准号: 10395222
• 负责人: Joel R Neilson
• 金额: $ 8万
• 依托单位: BAYLOR COLLEGE OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-04-20 至 2022-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10395222
• 关键词: Biochemical; Breast Epithelial Cells; Data; Epithelial Cells; Event; Experimental Models; Genes; Human; Malignant Neoplasms; Modeling; Myotonic dystrophy type 1; Neoplasm Metastasis; Normal tissue morphology; Pathway interactions; Play; Process; Proteins; RNA-Binding Proteins; Role; Solid Neoplasm; Surveys; System; Testing; Transforming Growth Factor beta; Translational Activation; Translations; Work; epithelial to mesenchymal transition; gene product; in vivo Model; insight; malignant breast neoplasm; mammary epithelium; metastasis prevention; mortality; multicatalytic endopeptidase complex; novel; prevent; therapeutic candidate; therapeutic target; tumor

By some estimates, tumor metastasis is responsible for over 90% of cancer mortality. At the cellular level, epithelial to mesenchymal transition (EMT) is the initiating event in tumor metastasis. We have been investigating the contribution of translational control to TGF-β-induced EMT in a breast epithelial model. Our preliminary data unambiguously demonstrate that the CELF1 RNA binding protein, most well known for its role in Type 1 Myotonic Dystrophy, is both necessary and sufficient for EMT in this system. In epithelial cells, the CELF1 protein is actively degraded via the proteasome. However, upon TGF-β addition and EMT, this protein is stabilized and appears to increase the translation of several target genes, some of which have already been defined as positive regulators of EMT. To our knowledge this is the first data directly demonstrating the role of this gene product in EMT. Our overall objective is to further elucidate the mechanism by which TGF-β induces EMT via the CELF1 protein. We predict that a more developed understanding of the cellular mechanisms at play in this pathway will reveal enzymatic activities playing critical roles in EMT, and that eventual therapeutic targeting of these activities may be viable therapeutic targets for the prevention of metastasis in early stage cancers. We hope to achieve our objective by testing our core hypothesis that induced stability of CELF1 protein drives EMT via translational activation of distinct downstream effector proteins. We propose doing this via three Specific Aims. First, we will identify the downstream effectors by which CELF1 promotes EMT and tumor metastasis in experimental models via a candidate approach. Using classical biochemical approaches, we will next establish the mechanism by which TGF-β treatment leads to an increase in CELF1 protein levels. Finally, we will determine to what extent misexpression of CELF1 impacts tumor colonization and metastasis in in vivo models, and survey a broad range of human breast cancers to determine whether CELF1 is misexpressed in these tumors as compared to normal tissue. The proposed work is directly relevant to cancer because EMT is a core mechanism underlying tumor metastasis. Identification of the enzymatic activities by which CELF1 stability and function are controlled in the context of EMT will reveal candidate therapeutic targets for the prevention of metastasis of early-stage cancers. Downstream effectors of the CELF1 protein may also prove to be potential therapeutic targets, but are certain to provide insight into the cellular mechanisms underlying EMT that may be translatable to a broad range of solid tumors.

据估计，肿瘤转移占癌症死亡率的90%以上。在手机上 从上皮到间充质转化(EMT)是肿瘤转移的始动事件。我们有 我一直在研究翻译控制在转化生长因子-β诱导的乳腺上皮细胞内皮细胞转化中的作用 模特。我们的初步数据明确地表明，CELF1 RNA结合蛋白，大多数 众所周知，它在1型强直性肌营养不良中的作用，是EMT在这方面的必要和充分条件 系统。在上皮细胞中，CELF1蛋白通过蛋白酶体被主动降解。然而，一旦 转化生长因子-β的加入和EMT，这种蛋白质是稳定的，并似乎增加了几个翻译 靶基因，其中一些已经被定义为EMT的正调控因子。致我们的 这是第一个直接证明该基因产物在EMT中的作用的数据。 我们的总体目标是进一步阐明转化生长因子-β通过 CELF1蛋白。我们预测，对细胞机制的更深入了解将在 这一途径将揭示酶活性在EMT中发挥关键作用，并最终治疗 靶向这些活性可能是预防早期转移的可行的治疗靶点。 分期癌症。我们希望通过测试我们的核心假设来实现我们的目标，即诱导稳定性 CELF1蛋白通过翻译激活不同的下游效应蛋白来驱动EMT。我们 建议通过三个具体目标来实现这一点。首先，我们将确定下游效应器， CELF1通过候选途径在实验模型中促进EMT和肿瘤转移。vbl.使用 经典的生化方法，接下来我们将建立转化生长因子-β治疗的机制 导致CELF1蛋白水平升高。最后，我们将确定错误表达在多大程度上 CELF1在体内模型中影响肿瘤的定植和转移，并调查了广泛的 以确定CELF1在这些肿瘤中是否错误表达 正常组织。 这项拟议的工作与癌症直接相关，因为EMT是肿瘤的核心机制 转移。影响CELF1稳定性和功能的酶活性鉴定 在EMT的背景下进行控制将揭示预防 早期癌症的转移。CELF1蛋白的下游效应器也可能被证明是 潜在的治疗靶点，但肯定能提供对潜在细胞机制的洞察 可翻译为多种实体肿瘤的EMT。