The Role of JNK in Glial Tumor Pathogenesis

JNK 在胶质瘤发病机制中的作用

• 批准号: 6503341
• 负责人: ALBERT J. WONG
• 金额: $ 31.44万
• 依托单位: THOMAS JEFFERSON UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-04-01 至 2007-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6503341
• 关键词: 3T3 cells; JUN kinase; angiogenesis; apoptosis; astrocytes; athymic mouse; biological signal transduction; carcinogenesis; cell proliferation; epidermal growth factor; glioblastoma multiforme; growth factor receptors; guanine nucleotide binding protein; guanosinetriphosphatases; human tissue; immunoprecipitation; mass spectrometry; mitogen activated protein kinase; neoplastic growth; platelet derived growth factor; receptor expression; thin layer chromatography; transcription factor; western blottings

DESCRIPTION (provided by applicant): Our long term goals are to understand the molecular mechanisms underlying glioblastoma multiforme, the most common and deadly among human brain tumors. The EGF receptor has been strongly implicated and much research on its downstream signaling has focused on the ERK signaling module. Unexpectedly, our work has instead led us to study a pathway not commonly considered downstream of the EGF receptor or in tumorigenesis, the JNK pathway. We have found that 86 percent of primary glioblastoma tumors show activation of a 54 kDa JNK isoform. EGF induces strong JNK activation in 69 percent of cell lines derived from glioblastoma tumors but only weak activation was observed in 6 normal cell lines. Further work in two tumor cell lines has indicated that JNK is important for anchorage independent growth and the prevention of apoptosis. We hypothesize that an important difference between glioblastoma tumors and normal tissues is that EGF receptor signals are also directed towards the JNK pathway. The goals of this application are to further study the mechanisms by which JNK becomes activated and how it contributes to multiple phenotypes. In Specific Aim #1, we will examine the mechanisms underlying the enhanced EGF induced activation of JNK seen in glioblastoma cell lines. Several points at which signals can be directed towards the JNK signaling module will be examined: 1) the small GTPases, Rac and Cdc42; 2) PI 3-kinase; and 3) Gab1. These molecules will be tested for increased activity/binding following EGF addition in glioblastoma cell lines as compared to normal astrocyte cell lines. Dominant negative versions of these molecules will be used to confirm their roles in JNK activation. In Specific Aim #2, we will determine which JNK isoform the 54 kDa form corresponds to using RNase protection. Next, we will identify the mechanisms by which it became preferentially phosphorylated. Most importantly, we will determine what properties this isoform has that might contribute to tumorigenesis. The localization of the 54 kDa isoform will be studied in tumor sections and the transcription factors that bind to this isoform in tumors will also be studied. In Specific Aim #3, we will evaluate the relative contribution of JNK and ERK to glial tumorigenesis. The notion that JNK contributes to tumorigenesis is relatively new and not well studied, especially in animal models, but there is a much more extensive literature on the contribution of ERK to tumorigenesis. Thus, we will attempt to clarify the relative contribution of these two signaling modules to these critical phenotypes in vivo: 1) tumor formation in athymic mice, 2) angiogenesis, 3) cell proliferation, and 4) prevention of apoptosis. This work will further enhance our knowledge of this novel signaling pathway in this human cancer and provide new avenues for diagnostics and therapeutics.

描述（由申请人提供）：我们的长期目标是了解 多形性胶质母细胞瘤的分子机制，最常见的， 致命的人类脑瘤。EGF的作用机制 其下游信号通路的研究主要集中在ERK信号通路上 module.出乎意料的是，我们的工作反而引导我们研究一种途径， 通常被认为是EGF受体的下游或在肿瘤发生中，JNK 通路我们发现86%的原发性胶质母细胞瘤肿瘤 54 kDa JNK同种型的活化。EGF诱导JNK活化69例 来自胶质母细胞瘤肿瘤的细胞系的百分比，但仅弱活化 在6个正常细胞系中观察到。在两种肿瘤细胞系中的进一步研究 表明JNK对锚定非依赖性生长是重要的， 防止细胞凋亡。我们假设， 胶质母细胞瘤肿瘤和正常组织是EGF受体信号也 针对JNK通路。该应用程序的目标是进一步 研究JNK被激活的机制以及它如何有助于 多种表型在具体目标#1中，我们将研究 在胶质母细胞瘤细胞中观察到的增强的EGF诱导的JNK活化的基础 线信号可以指向JNK的几个点 将检测以下信号传导模块：1）小GTP酶，Rac和Cdc 42; 2）PI 3-激酶;和3）Gab 1.这些分子将被检测是否增加 在胶质母细胞瘤细胞系中加入EGF后的活性/结合， 正常的星形胶质细胞系。这些分子的主要负性版本 将用于确认它们在JNK激活中的作用。在具体目标#2中， 将使用RNase确定54 kDa形式对应于哪种JNK同种型 保护接下来，我们将确定它成为 优先磷酸化。最重要的是，我们将确定 这种同种型具有可能有助于肿瘤发生的特性。的 将在肿瘤切片中研究54 kDa同种型的定位， 还将研究在肿瘤中与该同种型结合的转录因子。 在具体目标#3中，我们将评估JNK和ERK的相对贡献。 神经胶质肿瘤的发生JNK参与肿瘤发生的观点是 相对较新，没有得到很好的研究，特别是在动物模型中，但有 关于ERK对肿瘤发生的贡献的更广泛的文献。 因此，我们将试图澄清这两个相对的贡献 这些关键表型在体内的信号传导模块：1）肿瘤形成， 无胸腺小鼠，2）血管生成，3）细胞增殖，和4）预防 凋亡这项工作将进一步增强我们对这种新型信号的认识 在这种人类癌症中的途径，并提供新的诊断途径， 治疗学