TGF-B REGULATED GROWTH INHIBITORY GENES IN CANCER

TGF-B 调节癌症中的生长抑制基因

• 批准号: 3201396
• 负责人: FREDERICK T BOYD
• 金额: $ 13.84万
• 依托单位: UNIVERSITY OF MINNESOTA
• 依托单位国家: 美国
• 财政年份: 1992
• 资助国家: 美国
• 起止时间: 1992-09-01 至 1995-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3201396
• 关键词: cell growth regulation; complementary DNA; flow cytometry; fluorescent dye /probe; genetic library; genetic regulation; neoplasm /cancer genetics; neoplastic growth; nucleic acid sequence; tissue /cell culture; transfection; transforming growth factors

The research outlined in this proposal will investigate the growth inhibitory response of epithelial cells to Transforming Growth Factors-beta (TGF-beta). Changes in epithelial cell responsiveness to TGF-beta has been associated with the carcinogenic process of a large number of epithelial cancers. Further genetic evidence suggests that tumor suppressor genes are inactivated as part of the development of epithelial cancers. Since many tumor suppressor genes are growth inhibitory in the normal physiology of cells, it is possible that some elements of the TGF-beta growth inhibitory pathway of epithelial cells are tumor suppressor genes. The model system used is the mink lung epithelial cell line (CCL 64) in which the investigator has generated a panel of mutants defective in TGF-beta response- in some cases because of biochemically identifiable defects in the TGF-beta receptor. In addition, the investigator has developed a unique in vitro assay for the identification of growth inhibitory cDNAs. This assay is based on the dilution of a lipophilic fluorescent dye among daughter cells as cells divide. If a cell is transfected with a cDNA which slows the transfectants doubling time, the progeny of that cell will retain more dye over time. The population is allowed to grow for approximately four population doublings at which time the brightest cells in the population are isolated and cDNAs associated with that slowly growing population are identified. TGF-beta's growth-inhibitory effects will be investigated using this system by constructing cDNA libraries which are enriched for messages regulated by TGF-beta, transfecting these libraries into TGF-beta-nonresponsive Mv1Lu mutants, and identifying cDNAs induced by TGF-beta which can slow cells growth rates. These TGF-beta-regulated growth inhibitory genes will subsequently be screened for tumor suppressor activity by a variety of genetic and physiological criteria.

本提案中概述的研究将调查增长 上皮细胞对转化生长因子-β的抑制反应 （TGF-β）。 上皮细胞对 TGF-β 反应性的变化 与大量上皮细胞的致癌过程有关 癌症。 进一步的遗传证据表明肿瘤抑制基因 作为上皮癌发展的一部分而失活。 由于许多 肿瘤抑制基因在正常生理学中具有生长抑制作用 细胞中，TGF-β生长抑制的某些元素可能 上皮细胞途径是抑癌基因。 模型系统 使用的是水貂肺上皮细胞系（CCL 64），其中 研究人员已经产生了一组 TGF-β 有缺陷的突变体 反应-在某些情况下是由于生化上可识别的缺陷 TGF-β受体。 此外，研究人员还开发了一种 用于鉴定生长抑制 cDNA 的独特体外测定。 该测定基于亲脂性荧光染料的稀释 细胞分裂时的子细胞。 如果细胞被 cDNA 转染， 减慢转染子倍增时间，该细胞的后代将保留 随着时间的推移，会有更多的染料。 允许人口增长约 四次群体倍增，此时细胞中最亮的细胞 种群被分离出来，并且 cDNA 与缓慢生长的种群相关 人口已确定。 TGF-β的生长抑制作用是 通过构建 cDNA 文库，使用该系统进行了研究 富含 TGF-β 调节的信息，转染这些文库 转化为 TGF-β 无反应性 Mv1Lu 突变体，并鉴定由 TGF-β可以减缓细胞生长速度。 这些 TGF-β 调节的 随后将筛选生长抑制基因作为肿瘤抑制因子 活性由多种遗传和生理标准决定。