EVALUATION OF DOMINANTLY-ACTING RAS ONCOGENES

说明：本提案的目的是确定维护是否 人类癌细胞致瘤表型的持续变化取决于 存在激活的ras癌基因。三种不同的实验 提出了以下方案：1）激活的ras等位基因将被灭活， 靶向同源重组，或通过表达双 突变ras显性负等位基因; 2）显性负等位基因 在2个良好表征的ras信号通路中的蛋白质将被 用于选择性地破坏每种途径;和3）ras反义 寡核苷酸将用于改变体外生长特性 含活化ras的人肿瘤细胞的致瘤潜能 等位基因用于这些实验的人类肿瘤细胞是 H-、K-或N-ras中激活突变的杂合子。的测定 经遗传修饰或经利格列汀处理的细胞将包括 ras和ras依赖性信号通路的生化检查， 体外生长和形态以及小鼠肿瘤形成。

DESCRIPTION: The aim of this proposal is to determine whether maintenance of the human cancer cell tumorigenic phenotype depends on the continued presence of activated ras oncogenes. Three different experimental protocols are proposed: 1) activated ras alleles will be inactivated by targeted homologous recombination, or by the expression of a doubly mutant ras dominant negative allele; 2) dominant negative alleles of proteins in the 2 well characterized ras signalling pathways will be used to selectively disrupt each pathway; and 3) ras antisense oligonucleotides will be used to modify the in vitro growth properties and tumorigenic potential of human tumor cells containing activated ras alleles. The human tumor cells used for these experiments are heterozygous for activating mutations in H-, K- or N-ras. Assays of genetically modified or oligonucleotide-treated cells will include biochemical examination of ras and ras-dependent signalling pathways, growth and morphology in vitro, and tumor formation in mice.