DNA Methylation and GSTP1 Gene Regulation in Gliomas

描述（由申请人提供）：人类恶性神经胶质瘤是最常见的肿瘤之一。 难治性的人类肿瘤。因此，继续迫切需要 需要更好地了解潜在的分子机制， 这些肿瘤的恶性生长、进展和治疗失败。之间 脑肿瘤和其他人类肿瘤中最常见的分子改变是 谷胱甘肽S-转移酶P1（GSTP 1）基因的过度表达。这 应用是基于对人类GSTP 1基因的几个重要发现 我们实验室制造的神经胶质瘤其中包括发现 GSTP 1基因位点的化感多态性和GSTP 1 神经胶质瘤的基因表达是高度异质性的， 患者存活率和对治疗反应指标。我们的目标是 应用是为了更好地了解调节的分子机制， 恶性胶质瘤中GST-π的差异表达。我们将测试 假设GSTP 1在胶质瘤中表达的异质性导致 GSTP 1基因的不同转录活性， GSTP 1基因5 '区CpG甲基化的差异导致 染色质结构的改变和转录因子与 GSTP 1启动子，其最终解释了GSTP 1 胶质瘤之间的表达。使用原代标本和细胞系， 人类恶性胶质瘤，我们将a）确定在何种程度上分化 恶性胶质瘤中GSTP 1的表达在转录水平受到调控 B）确定细胞中CpG的甲基化状态与细胞中CpG的甲基化状态之间的关系。 五个？GSTP 1基因的转录活性和表达 GSTP 1基因在神经胶质瘤中的表达，并检查不同的GSTP 1等位基因是否 差异甲基化和表达，以及是否GSTP 1基因甲基化 状态与神经胶质瘤中的耐药性相关; c）研究 GST P1 5 '区CpG甲基化对转录的影响 与GSTP 1启动子区结合的因子和对GSTP 1启动子功能的影响; d） 检查GSTP 1基因甲基化是否与 GSTP 1基因组蛋白乙酰化/去乙酰化与染色质结构 基因座，以及这些是否共同决定GSTP 1在胶质瘤中的表达。的 拟议的研究是一项重点突出的创新研究工作。的 结果应该产生重要的DNA甲基化相关的新信息， GST P1基因在人脑胶质瘤中过度表达的机制 并将有助于在合理的发展更有效的努力 药物和治疗策略。结果也应该导致 为了更好地理解恶性过程，不仅在胶质瘤中， 也在许多其他人类癌症中表现为GST P1过表达。

DESCRIPTION (provided by applicant): Human malignant gliomas are among the most intractable of human tumors to therapy. There is, therefore, a continued urgent need for a better understanding of the molecular mechanisms underlying the malignant growth, progression and therapeutic failure in these tumors. Among the most common molecular alteration in brain and other human tumors is the over-expression of the glutathione S-transferase P1 (GSTP1) gene. This application is based on several important findings on the GSTP1 gene in human gliomas that have been made in our laboratory. These include the discovery of allelopolymorphism of the GSTP1 gene locus and the demonstration that GSTP1 gene expression in gliomas is highly heterogeneous and is a strong prognostic indicator of patient survival and response to therapy. Our goal in this application is to better understand the molecular mechanisms that regulate differential GST-pi expression among malignant gliomas. We will test the hypothesis that the heterogeneity in GSTP1 expression among gliomas results from differential transcriptional activity of the GSTP1 gene and that differences in methylation of CpGs in the 5'-region of the GSTP1 gene results in altered chromatin structure and altered transcription factor binding to the GSTP1 promoter, which ultimately accounts for the differences in GSTP1 expression between gliomas. Using both primary specimens and cell lines of human malignant gliomas, we will a) Determine be extent to which differential GSTP1 expression among malignant gliomas is regulated at the transcriptional level; b) Determine the relationship between methylation status of CpGs in the 5?-region of the GSTP1 gene and the transcriptional activity and expression of the GSTP1 gene in gliomas, and examine whether different GSTP1 alleles are differentially methylated and expressed, and whether GSTP1 gene methylation status is associated with drug resistance in gliomas; c) Investigate the effects of the methylation of CpGs in the GSTP1 5'-region on transcription factor binding to the GSTP1 promoter region and on GSTP1 promoter function; d) Examine whether methylation of the GSTP1 gene is associated with altered histone acetylation/deacetylation and chromatin structure at the GSTP1 gene locus, and whether these together determine GSTP1 expression in gliomas. The proposed studies represent a well-focused innovative research effort. The results should yield important new information on DNA methylation-related mechanisms involved in the over-expression of the GSTP1 gene in human gliomas and will contribute to efforts in the rational development of more effective agents and treatment strategies for these tumors. The results should also lead to a better understanding of the malignant process, not only in gliomas, but also in many other human cancer characterized be GSTP1 over-expression.