INTERACTION OF ANTITUMOR AGENTS WITH ACTIVATED ONCOGENES

这个应用程序的总体目标是确定DNA损伤 由临床上使用的烷基化抗肿瘤药物生产的可以 改变激活的癌基因的表达，这些癌基因对 肿瘤形成表型的维持。使用Maxam-Gilbert DNA测序方法学初步研究将确定 氮芥末(HN-2)、L-苯丙氨酸芥末(L-PAM)和两种 环磷酰胺衍生物(4-HC和C2)具有DNA序列 对来自几个克隆编码区的攻击的偏好 激活的致癌基因。这种DNA损伤对 受损癌基因序列的转录将在#年进行研究。 一种体外RNA转录系统。其序列选择性 这些药物随后将在治疗的肿瘤细胞中进行研究，方法是 确定癌基因和其他基因中的烷基化模式 关键细胞基因因抗肿瘤作用的不同而不同 探员们。这些实验也将使研究修复 激活的癌基因中的DNA损伤。然后这些药物将被 研究DNA损伤特性，测量细胞毒性 集落形成实验及其对癌基因表达的影响 Dot和Northern印迹分析)在人肿瘤细胞中的表达 这些致癌基因被激活的品系。细胞系具有单个 复制过度表达的癌基因将与具有 同一癌基因的扩增拷贝以确定是否有抗- 肿瘤药物或多或少对癌基因失活有效。 细胞杀伤率取决于癌基因的拷贝数。从这些 研究希望可以选择抗肿瘤药物 用于对抗特定的癌基因，这是由于 特定的抗肿瘤药物可有效灭活关键 肿瘤细胞中的癌基因。

The overall goal of this application is to determine if DNA damage produced by clinically used alkylating anti-tumor agents can alter the expression of activated oncogenes which are critical for the maintenance of the tumorigenic phenotype. Using Maxam-Gilbert DNA sequencing methodology initial studies will determine if nitrogen mustard (HN-2), L-phenylalanine mustard (L-PAM), and two cyclophosphamide derivatives (4-HC and C2) have DNA sequence preferences for attack in cloned coding regions from several activated oncogenes. The effects of this DNA damage on transcription of the damaged oncogene sequence will be studied in an in vitro RNA transcription system. The sequence selectivity of the agents will then be studied in treated tumor cells by determining if alkylation patterns in oncogenes and other critical cellular genes differ with the different anti-tumor agents. These experiments will also allow the study of the repair of DNA damage in activated oncogenes. The drugs will then be studied for DNA damaging properties, cytotoxicity as measured by colony formation assays, and effects on oncogene expression (as measured by Dot and Northern blot analysis) in human tumor cell lines having these oncogenes activated. Cell lines having single copy over-expressed oncogenes will be compared to cell lines having amplified copies of the same oncogene to determine if the anti- tumor agents are more, or less, effective at oncogene inactivation and cell killing depending on the oncogene copy number. From these studies it is hoped that anti-tumor agents might be selected for use against specific oncogenes due to the ability of the particular anti-tumor agent to efficiently inactivate critical oncogenes in the tumor cell.