GENETIC ALTERATIONS IN MODELS OF COLONIC NEOPLASTIC PROGRESSION

结肠肿瘤进展模型中的基因改变

• 批准号: 6236886
• 负责人: IAN CHARLES SUMMERHAYES
• 金额: $ 18.43万
• 依托单位: BETH ISRAEL DEACONESS MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 1997
• 资助国家: 美国
• 起止时间: 1997-03-07 至 1998-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6236886
• 关键词: DNA repair; athymic mouse; biomarker; cell line; colorectal neoplasms; gastrointestinal epithelium; gene complementation; gene expression; gene mutation; genotype; human tissue; laboratory mouse; laboratory rat; molecular cloning; monoclonal antibody; neoplasm /cancer genetics; neoplastic process; neoplastic transformation; phenotype; polymerase chain reaction; preneoplastic state; protein tyrosine kinase; tissue /cell culture; transfection; tumor suppressor genes; western blottings

The molecular events underlying colonic neoplastic progression potentially involve at least three classes of genetic elements: oncogenes, tumor suppressor genes and DNA repair genes. Although alterations in specific loci have been identified in different colonic lesions, the consequences of activation or inactivation and the interplay between these altered elements in the colonic neoplastic process remain little understood. The long term goal of the work outlined in this proposal is to link genotypic change with the in vivo phenotype generated and to gain an understanding of the individual and cumulative role of genetic changes underlying colon carcinogenesis. Toward this end we have developed a panel of immortalized rat colon epithelial cell lines which act as a vehicle for analysis of the action of both individual and combination genes. The desirability of a human counterpart of these cell lines is self evident and we propose to use culture techniques we have established, to achieve this goal. Immortalized cell lines will be used to isolate novel phosphotyrosyl proteins associated with early events in neoplastic progression, to which monoclonal antibodies will be raised and assessed as potential markers of change in colon mucosa. Analysis of individual genetic events implicated in colon carcinogenesis will be directed not only toward gaining an understanding of their role in progression involving interaction with other altered genes, but also the cellular events accompanying activation or inactivation. These studies will focus on cellular events associated with c-src activation in colon epithelium including the identification and isolation of cellular substrates and protein interactions involved in src signaling pathways. From the use of a heterotopic colon model, with the ability to localize implanted cells, we propose to establish genotypic/phenotypic links associated with altered genetic loci. Alternative use of the heterotopic model is proposed to evaluate possible complementation between APC and K-ras gene mutations in early stages of colonic neoplastic progression. Early and late stage events associated with mutation of the MSH2 locus in colonic tissue will be performed in a mouse model currently under construction.

结肠肿瘤进展潜在的分子事件 至少涉及三类遗传因素：癌基因、肿瘤 抑制基因和DNA修复基因。虽然在特定情况下的更改 已经在不同的结肠病变中发现了基因座，后果是 激活或失活以及这些改变之间的相互作用 结肠肿瘤过程中的因素仍然知之甚少。这个 本提案中概述的工作的长期目标是将基因分型 随着体内产生的表型而变化并获得理解 基因改变在结肠中的个体和累积作用 致癌。为此，我们开发了一组不朽的 作为分析大鼠结肠上皮细胞系的载体 个体基因和组合基因的作用。一种可取的 这些细胞系的人类对应物是不言而喻的，我们建议 使用我们已经建立的培养技术来实现这一目标。 永生化细胞系将用于分离新的磷酸酪氨酰 与肿瘤进展的早期事件相关的蛋白质，到 将提出并评估单抗作为潜在的标记物 结肠粘膜改变。所涉及的个体遗传事件的分析 结肠癌的发生不仅仅是为了获得一个 理解它们在涉及相互作用的进程中的作用 其他改变的基因，以及伴随激活的细胞事件 或失活。这些研究将集中在相关的细胞事件上 C-src在结肠上皮中的激活，包括鉴定和 参与SRC的细胞底物的分离和蛋白质相互作用 信号通路。来自异位结肠模型的使用， 定位移植细胞的能力，我们建议建立 与改变的遗传座位相关的基因类型/表型链接。 提出了异位模型的另一种用途，以评估可能性 乳腺癌早期APC和K-ras基因突变的互补作用 结肠肿瘤进展。关联的早期和后期事件 在结肠组织中进行MSH2基因突变的患者将在 目前正在建造的老鼠模型。