Transcriptional & cell cycle control by dietary indoles

转录的

• 批准号: 6815112
• 负责人: GARY L FIRESTONE
• 金额: $ 27.41万
• 依托单位: UNIVERSITY OF CALIFORNIA BERKELEY
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-07-30 至 2009-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6815112
• 关键词: MCF7 cell; athymic mouse; biological signal transduction; breast neoplasms; cell growth regulation; cell proliferation; chemoprevention; cyclin dependent kinase; genetic promoter element; genetic regulation; genetic transcription; indoles; intermolecular interaction; neoplastic cell; nutrition aspect of cancer; nutrition related tag; plasmids; posttranslational modifications; protein sequence; transcription factor; transfection /expression vector; vegetables

DESCRIPTION (provided by applicant): Indole-3-carbinol (I3C), a naturally occurring compound in vegetables such as cabbage, broccoli and Brussel's sprouts, and its dimerization product 3-3'-diindolylmethane (DIM) are promising chemotherapeutic and chemopreventative agents for human reproductive cancers. We have demonstrated that the direct exposure of human breast cancer cells to I3C or DIM induces a stringent G1 cell cycle arrest through a multistep signaling cascade that controls expression, activity and cellular utilization of key cell cycle components. I3C, but not DIM, down-regulates cyclin dependent kinase-6 (CDK6) expression and promoter activity, whereas, DIM selectively and rapidly stimulates expression and promoter activity of p21Waf1/Cip1, a critical inhibitor of certain CDKs. The indole regulation of cell cycle gene expression result from specific changes in Sp1 transcription factor-promoter interactions. We have recently discovered that I3C, but not DIM, alters the size, composition and subcellular localization (nuclear to cytoplasm) of the CDK2 protein complex, and a novel 85 kDa protein was uncovered that associates with the CDK2 protein complex in an I3C dependent manner. Thus, the transcriptional control of CDK6 and p21Waf1/Cip1, and the posttanslational regulation of CDK2 protein complex utilization are newly defined down-stream targets of the anti-proliferative indole signaling pathway in human breast cancer cells. Our hypothesis is that I3C and DIM induce a G1 cell cycle arrest of human reproductive cancer cells by activating complementary and distinct cascades that that subsequently control the transcription and posttranslational utilization of key cell cycle components. The indole regulated transcription factors, in addition to Spl, that target the CDK6 and p21Waf1/Cip1 promoters will be identified by interactions with indole responsive regions of cell cycle gene promoters, and functionally tested in a cellular text by manipulation of their expression and/or activity. The novel 85 kDa protein that interacts with the CDK2 protein complex in an I3C dependent manner will be defined and characterized for its role in the I3C disruption of the CDK2 protein complex. The actions of the I3C regulated cell cycle components on cancer cell invasion properties, and in the formation of human breast cancer cell-derived tumors will be assessed using in vitro and in vivo strategies. Our collaborative studies represent the first experimental steps necessary to understand the transcriptional and posttranslational mechanisms by which natural indoles control the cell cycle of human breast cancer cells. This information will be particularly valuable to develop new classes of I3C-based therapeutics for reproductive cancers.

描述（由申请人提供）：吲哚-3-甲醇（I3C），一种天然存在于蔬菜中的化合物，例如卷心菜，西兰花和布鲁塞尔的芽菜，以及其3-3'-二烷基甲烷（DIM）的二聚化产品是有希望的化学疗法和化学疗法的人类的化学疗法和化学剂的人体复制犬。我们已经证明，人类乳腺癌细胞直接暴露于I3C或DIM通过多步信号传导级联反应，可控制钥匙细胞周期成分的表达，活性和细胞利用。 I3C，但不降低，下调细胞周期蛋白依赖性激酶-6（CDK6）表达和启动子活性，而暗线化和迅速刺激P21WAF1/CIP1的表达和启动子活性，P21WAF1/CIP1（某些CDKS的关键抑制剂）的表达和启动子活性。细胞周期基因表达的吲哚调节是由SP1转录因子促进剂相互作用的特定变化引起的。我们最近发现，I3C（但不是昏暗的）改变了CDK2蛋白复合物的大小，组成和亚细胞定位（核至细胞质），并发现了一种新型的85 kDa蛋白，以与I3C相关的方式与CDK2蛋白复合物相关联。因此，CDK6和P21WAF1/CIP1的转录控制以及CDK2蛋白复合物利用的转换后调节是人类乳腺癌细胞中抗增殖性吲哚信号通路的新定义的下游靶标。 我们的假设是I3C和DIM通过激活互补和不同的级联反应，从而诱导人类生殖癌细胞的G1细胞周期停滞，从而控制关键细胞周期成分的转录和翻译后利用。除SPL之外，还将通过与细胞周期基因启动子的吲哚响应区域的相互作用来识别吲哚调节的转录因子，该因子靶向CDK6和P21WAF1/CIP1启动子，并通过操纵其表达和/或活性在细胞文本中进行了功能测试。以I3C依赖性方式与CDK2蛋白复合物相互作用的新型85 kDa蛋白将因其在CDK2蛋白复合物的I3C破坏中的作用而定义和表征。 I3C调节细胞周期成分对癌细胞浸润特性的作用以及人类乳腺癌细胞衍生的肿瘤的形成将使用体外和体内策略进行评估。我们的协作研究是了解自然吲哚控制人类乳腺癌细胞细胞周期的转录和翻译后机制所需的第一个实验步骤。这些信息对于开发新的基于I3C的疗法的生殖癌症将特别有价值。