GROWTH ARREST IN NORMAL AND CANCER CELLS

正常细胞和癌细胞生长停滞

• 批准号: 6102318
• 负责人: Thea D Tlsty
• 金额: $ 17.31万
• 依托单位: UNIV OF NORTH CAROLINA CHAPEL HILL
• 依托单位国家: 美国
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-05-01 至 2001-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6102318
• 关键词: aneuploidy; apoptosis; cell fusion; cell growth regulation; cell population study; chemical carcinogen; chromosome aberrations; clone cells; cytogenetics; fibroblasts; flow cytometry; fluorescent dye /probe; gene expression; hybrid cells; in situ hybridization; natural gene amplification; neoplasm /cancer genetics; neoplastic cell; oncogenes; southern blotting; tumor suppressor genes

We have found that there is a striking difference between normal, diploid cells and tumorigenic ell in their ability to amplify a given endogenous gene. Amplification frequency is high in tumorigenic cells (10-3), lower in nontumorigenic, preneoplastic cells (10-5) and undetectable in normal, diploid cells (lessor10-9). To investigate the genetic control of gene amplification, amplification frequency was measured in hybrids formed between tumorigenic cells and normal, diploid cells. The ability to amplify an endogenous gene behaved as a recessive genetic trait. Amplification frequency in the hybrid cells was suppressed by over five orders of magnitude (10-3 to lessor10-8). We observed that diploid cells that had not detectable frequency of gene amplification are arresting in the cell cycle when placed in the metabolic inhibitor, PALA. Tumorigenic cells do not arrest but proceed to make a choice between growth (containing amplified target genes) or suicide, the activation of apoptosis. In this application we wish to address two questions. 1) is there a functional connection between the metabolic growth arrest in normal cells and their ability to amplify? and 2) is apoptosis the default alternative? We will approach these goals by examining the relationship between growth arrest and amplification using flowcytometry as a method of detection we can determine if the cellular arrest generates amplification intermediates. We will also examine amplification of genes that are not directly connected to the production of nucleotide precursors. Finally, we will ask if genes that suppress amplification ability suppress apoptosis. We will use the somatic cell hybrids we have characterized for these purposes.

我们发现正常的二倍体之间存在明显的差异 细胞和肿瘤ELL具有扩增给定内源性的能力 基因。 肿瘤细胞的扩增频率很高（10-3），较低 在非肿瘤的，肿瘤的细胞（10-5）中，在正常情况下无法检测到 二倍体细胞（Lessor10-9）。 研究基因的遗传控制 放大，放大频率在形成的杂种中测量 在肿瘤细胞和正常的二倍体细胞之间。 能力 放大性内源基因表现为隐性遗传特征。 杂交细胞中的扩增频率被抑制超过五个 数量级（10-3至Lessor10-8）。 我们观察到二倍体细胞 无法检测到基因扩增的频率正在阻止 将细胞周期放置在代谢抑制剂Pala中时。 肿瘤 细胞不会逮捕，但继续在生长之间做出选择（包含 放大靶基因）或自杀，凋亡的激活。 在这个 应用我们希望解决两个问题。 1）是否有功能 正常细胞中的代谢生长停滞及其它们的联系 能力放大？ 2）凋亡是默认替代方案吗？ 我们将 通过检查增长逮捕之间的关系来实现这些目标 并使用流循环仪作为检测方法进行扩增我们可以 确定细胞停滞是否会产生放大中间体。 我们 还将检查未直接连接到与的基因的放大 核苷酸前体的产生。 最后，我们会问是否基因 抑制放大能力抑制凋亡。 我们将使用 我们为这些目的而表征的体细胞杂种。