NCI CLINICAL INVESTIGATOR AWARD PROGRAM

遗传重排是体细胞可能是一个重要的 导致细胞恶性潜能的机制。证据 提示癌基因可能通过易位和 多种人类恶性肿瘤与一种特定的 核型异常支持这一概念。然而，几乎没有什么是 了解分子中涉及的机制 重排或基因重组。使用变种人 单纯疱疹病毒(HSV)作为探针，有可能开发出一种 真核细胞中基因重组的检测系统，以及 将正常细胞与来自患者的正常细胞进行比较 DNA修复途径的异常。之间的重组 单纯疱疹病毒(HSV-1)突变体具有不重叠 胸苷激酶或DNA的互补突变 聚合酶基因座是可以定量的。这些研究将确定 如果共感染的HSV-1之间的基因重组受到调控 通过先前对人类细胞的DNA损伤。血管紧张素转换酶抑制剂的作用 大分子合成(蛋白质合成和转录 在基因重组上)将有助于我们的 理解这是否是一种可诱导的现象 人类细胞。 细胞功能的修饰剂，如蛋白酶抑制剂，3- 氨基苯甲酰胺和佛波酯对姐妹色的调节 交换，并可能影响DNA修复途径。我们会 确定这些药物是否通过以下方式调节基因重组 比较预先处理的细胞的水平或重组 这两种药物中的任何一种，都有未经处理的细胞。这些研究可能 帮助阐明这些细胞通路对于 基因重组的表达。 在对宿主细胞上的基因重组进行量化的研究中 患有特定DNA修复障碍的个人(例如，Bloom 综合征，Fanconi贫血)将决定 这两个突变体表达的重组水平不同。 与在正常细胞中观察到的结果不同。特定形式的效果 基因重组对这些细胞造成的DNA损伤将是 测定，连同蛋白水解酶抑制剂和3- 在这个环境中的氨基苯甲酰胺。 以确定这些细胞暴露之前被识别为 重组基因与突变子的表达有关 表型我们将使用一种检测突变的方法 单纯疱疹病毒1型ts突变体对ts+(非温度)的回复 敏感)表型。

Genetic rearrangement is somatic cells may be an important mechanism contributing to a cell's malignant potential. Evidence suggesting that oncogenes may be activated by translocation and the association of multiple human malignancies with a specific karyotypic abnormalities supports this concept. However, little is known about the mechanisms that are involved in molecular rearrangement or genetic recombination. Employing mutants of Herpes Simplex Virus (HSV) as probes it is possible to develop an assay system for genetic recombination in eukaryotic cells, and compare normal cells with those derived from patients having abnormalities in DNA repair pathways. Recombination between Herpes Simplex Virus (HSV-1) mutants having nonoverlapping complementary mutations in the thymidine kinase or DNA polymerase loci can be quantitated. These studies will determine if genetic recombination between co-infected HSV-1 is modulated by prior DNA damage to human cells. The effect of inhibitors of macromolecular synthesis (protein synthesis and transcription of mRNA) on genetic recombination will contribute to our understanding of whether this is an inducible phenomenon in human cells. Modifiers of cell function such as protease inhibitors, 3- aminobenzamide and phorbol esters modulate sister chromatic exchange and may affect DNA repair pathways. We will determine if these agents modulate genetic recombination by comparing the level or recombination in cells pretreated with either of these agents, with untreated cells. These studies may help elucidate those cellular pathways that are important for the expression of genetic recombination. In studies quantitating genetic recombination on host cells from individuals with specific DNA repair disorders (e.g., Bloom Syndrome, Fanconi's anemia) will determine whether either or both of these mutants express levels of recombination different from that observed in normal cells. The effects of specific forms of DNA damage to these cells on genetic recombination will be determined, along with the effects of protease inhibitors and 3- aminobenzamide in this setting. To determine if those cell exposures previously identified as recombinogenic are associated with expression of a mutator phenotype we will employ an assay for mutagenesis that measured reversions of ts mutants of HSV-1 to the ts+ (non-temperature sensitive) phenotype.