Identification of Green Tea Polyphenol-Targeted Genes

绿茶多酚靶向基因的鉴定

• 批准号: 6681266
• 负责人: STEPHEN De HSU
• 金额: $ 14.14万
• 依托单位: AUGUSTA UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-06-12 至 2005-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6681266
• 关键词: RNA; apoptosis; biological signal transduction; chemoprevention; cysteine endopeptidases; flavonoids; gene expression; gene induction /repression; genetic transcription; genetic translation; head /neck neoplasm; keratinocyte; neoplasm /cancer genetics; northern blottings; polymerase chain reaction; squamous cell carcinoma; tea; tissue /cell culture; western blottings

DESCRIPTION (provided by applicant): Green tea polyphenols appear to be chemopreventive against certain cancers, including oral cancer; but how cancer cells succumb while normal cells survive this polyphenol exposure is not known. Lack of this information prevented clinical uses of polyphenols for oral cancer chemoprevention or treatment. The long-term goal of this investigation is to elucidate the signal pathways and mechanisms by which green tea polyphenols differentially target normal and malignant cells to direct protective or apoptotic effects. Preliminary data from our laboratories have demonstrated that normal epithelial cells express p57 (KIP2) in response to green tea polyphenols in a dose- and time-dependent manner. We propose a novel concept, that green tea polyphenols are able to activate two pathways: 1) a p57-mediated survival pathway, and/or 2) a caspase 3-dependent apoptosis pathway. The hypotheses to be tested is that p57 induction by green tea polyphenols in normal epithelial cells may serve an anti-apoptotic function, absence of the p57 response in malignant cells may result in induction of caspase 3-dependent apoptosis. The immediate goal of this proposal is to identify the survival or apoptotic genes that are regulated by green tea polyphenols. In this proposed project, the survival/apoptosis gene expression profile will be determined following green tea polyphenol exposure, in normal human epidermal keratinocytes and in human oral squamous cell carcinoma cells. Specifically, the levels of p57 expression induced by the most potent green tea polyphenol, (-)- epigallocatechin-3-gallate (EGCG), in normal human epithelial cells will be determined. Using RT-PCR, mRNA stability assay, Northern and Western blot analyses, the relationship between transcription/translation levels of p57 induction and the time/dose of EGCG will be established. The RNA samples at specific time points will be subjeted to gene array analysis and profiling. Not only will the expression profile of those genes that are either activated or suppressed by EGCG in normal or tumor cells, but promising cellular targets for future chemotherapeutic intervention may be identified. Data generated from this proposal may reveal novel drug targets for treatment of head and neck cancer.

描述（由申请人提供）：绿色茶多酚似乎对某些癌症，包括口腔癌具有化学预防作用;但癌细胞如何屈服而正常细胞在这种多酚暴露下存活尚不清楚。缺乏这方面的信息阻碍了多酚在口腔癌化学预防或治疗中的临床应用。本研究的长期目标是阐明绿色茶多酚差异靶向正常和恶性细胞以直接保护或凋亡作用的信号通路和机制。我们实验室的初步数据表明，正常上皮细胞表达p57（KIP 2），以响应绿色茶多酚的剂量和时间依赖性的方式。我们提出了一个新的概念，即绿色茶多酚能够激活两条途径：1）p57介导的存活途径，和/或2）caspase 3依赖的凋亡途径。有待检验的假设是，在正常上皮细胞中由绿色茶多酚诱导的p57可能具有抗凋亡功能，在恶性细胞中p57应答的缺失可能导致诱导半胱天冬酶3依赖性凋亡。这项提议的直接目标是鉴定受绿色茶多酚调节的存活或凋亡基因。在这个拟议的项目中，生存/凋亡基因表达谱将确定以下绿色茶多酚暴露，在正常的人表皮角质形成细胞和人口腔鳞状细胞癌细胞。具体地，将测定由最有效的绿色茶多酚（-）-表没食子儿茶素-3-没食子酸酯（EGCG）在正常人上皮细胞中诱导的p57表达水平。采用RT-PCR、mRNA稳定性测定、北方和Western印迹分析，建立p57诱导的转录/翻译水平与EGCG的时间/剂量之间的关系。将对特定时间点的RNA样本进行基因阵列分析和分析。不仅将在正常或肿瘤细胞中被EGCG激活或抑制的那些基因的表达谱，而且可以鉴定未来化疗干预的有希望的细胞靶点。从这个提议中产生的数据可能会揭示治疗头颈癌的新药物靶点。