MOLECULAR MECHANISM IN RESISTANCE TO FOLATE ANALOGUES

抵抗叶酸类似物的分子机制

• 批准号: 3164383
• 负责人: ROBERT T SCHIMKE
• 金额: $ 33.01万
• 依托单位: STANFORD UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1977
• 资助国家: 美国
• 起止时间: 1977-05-01 至 1990-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3164383
• 关键词: dihydrofolate reductase; drug resistance; extrachromosomal DNA; fibroblasts; folate; folate antagonist; gene expression; genetic manipulation; genome; immunologic techniques; messenger RNA; methotrexate; molecular oncology; neoplasm /cancer chemotherapy; neoplasm /cancer genetics; neoplastic cell; nucleic acid metabolism; nucleic acid sequence; nutrition related tag; tissue /cell culture; virus RNA

The long-term objectives of this grant are to increase understanding of the mechanisms whereby cultured cells and tumors change genetic properties by the process of gene amplification, predominately with studies on resistance to methotrexate. The studies to be undertaken include: 1) an analysis of the nucleotide sequences constituting promoter regions of the dihydrofolate reductase gene, and studies on the synthesis and metabolism of the dihydrofolate reductase mRNA in the cell cycle; 2) an analysis of the propensity of normal, malignant, and metastatic breast epithelium to undergo spontaneous or induced amplification of the dihydrofolate reductase gene as detected by use of the fluorescence activated cell sorter and molecular biology technology; 3) an analysis of resistance to methotrexate that is associated with an unstable phenotype and increased ability to bind methotrexate at 4 degrees, and which has the properties of an altered transport of methotrexate, employing a combination of techniques to characterize the putative overproduced protein and its gene; 4) an attempt to generate resistance to radiomimetic drugs in such a fashion as to select for cells in which there is an increased capability for DNA recombination which results in the resistance phenotype by a gene amplification mechanism.

这笔赠款的长期目标是增进对 培养细胞和肿瘤通过以下方式改变遗传特性的机制 基因扩增过程，主要是耐药性研究 甲氨蝶呤。 需要进行的研究包括： 1) 分析 构成二氢叶酸启动子区的核苷酸序列 还原酶基因及其合成与代谢研究 细胞周期中的二氢叶酸还原酶 mRNA； 2）分析 正常、恶性和转移性乳腺上皮的倾向 经历二氢叶酸还原酶的自发或诱导扩增 使用荧光激活细胞分选仪检测到的基因 分子生物学技术； 3）甲氨蝶呤耐药性分析 这与不稳定的表型和增强的结合能力有关 甲氨蝶呤在 4 度时具有改变的特性 甲氨蝶呤的运输，采用多种技术的组合 描述假定的过量产生的蛋白质及其基因的特征； 4）尝试 以这样的方式产生对拟放射药物的抗性，以便选择 对于 DNA 重组能力增强的细胞 这通过基因扩增机制导致抗性表型。