Role of the Oxidative Stress Pathway in Drug Resistance

氧化应激途径在耐药性中的作用

• 批准号: 6743721
• 负责人: RANDY S STRICH
• 金额: $ 28.26万
• 依托单位: RESEARCH INST OF FOX CHASE CAN CTR
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-05-01 至 2008-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6743721
• 关键词: Saccharomyces cerevisiae; antineoplastics; biological signal transduction; cell line; cisplatin; cyclins; drug resistance; etoposide; fluorouracil; free radical oxygen; gene environment interaction; gene expression; gene targeting; genetic regulation; genetic transcription; human genetic material tag; methotrexate; microarray technology; mitomycin C; neoplasm /cancer chemotherapy; neoplastic cell; oxidative stress; phosphatidylinositols; phospholipase C; tissue /cell culture

DESCRIPTION (provided by applicant)Cellular resistance to anti-cancer agents is the predominant reason why chemotherapy regimens fail to eradicate disseminated malignancies. Therefore, elucidating the resistance mechanisms is of great importance for improving patient outcome. Several mechanisms for drug resistance have been identified including elevated drug pump activity and p53 mutation. In addition, the drug sensitivity of many tumors is influenced by induction of the stress response pathway. Moreover, the pathway that responds to reactive oxygen species (ROS) appears to be of singular importance for influencing drug sensitivity. However, the molecular mechanisms underlying the role of the ROS pathway in altering the drug response are largely unknown. The long-term goal of this proposal is to fully describe the ROS response system and determine how this pathway influences drug sensitivity in both normal and transformed cells. Toward this goal, we have chosen to study the relationship between the oxidative stress pathway and drug response in the budding yeast S. cerevisiae. Previous studies from this laboratory have identified two critical regulators that control both the oxidative stress-induced signal transduction pathway and gene expression. Ume3p is the yeast C-type cyclin that, rather than control the cell cycle, represses the transcription of several stress response genes. To relieve this repression, Ume3p is destroyed in cells exposed to oxidative stress. This destruction requires the conserved signaling molecule phosphatidylinositol-specific phospholipase C (PLC1). The importance of Plc1p-directed destruction of Ume3p is underscored by the finding that deleting the cyclin can rescue plc1 mutants from stress-induced cell death. The conservation of this pathway is supported by two findings. First, Plc1p is most similar to mammalian Plc-gamma, which also transduces an oxidative stress signal. In addition, the human cyclin C is also destroyed in response to stress in both human and yeast cells. The proposal combines the powerful genetic and molecular tools available in yeast to dissect the oxidative stress signaling pathway and determine its nuclear targets. We will combine our genetic system with microarray analysis to pinpoint genes whose expression is essential for viability in response to ROS. Finally, these genes will be ectopically activated or deleted in both yeast and human cells to determine their role in drug susceptibility or resistance.

描述（由申请人提供）对抗癌药的细胞耐药性是化学疗法方案无法消除传播性恶性肿瘤的主要原因。因此，阐明抗药性机制对于改善患者预后至关重要。已经确定了几种耐药性机制，包括升高的药物泵活性和p53突变。另外，许多肿瘤的药物敏感性受到应力反应途径的诱导影响。此外，对活性氧（ROS）响应的途径似乎对影响药物敏感性至关重要。但是，ROS途径在改变药物反应中作用的基础机制是未知的。该建议的长期目标是充分描述ROS响应系统，并确定该途径如何影响正常细胞和转化细胞的药物敏感性。为了实现这一目标，我们选择研究酿酒酵母酿酒酵母中氧化应激途径与药物反应之间的关系。该实验室的先前研究已经确定了两个关键调节剂，这些调节剂控制着氧化应激诱导的信号转导途径和基因表达。 UME3P是酵母C型细胞周期蛋白，而不是控制细胞周期，而是抑制了几种应激反应基因的转录。为了缓解这种抑制，UME3P在暴露于​​氧化应激的细胞中被破坏。这种破坏需要保守的信号分子磷脂酰肌醇特异性磷脂酶C（PLC1）。 PLC1P指导的UME3P的破坏的重要性强调了删除细胞周期蛋白可以从应激诱导的细胞死亡中拯救PLC1突变体的发现。该途径的保护得到了两个发现的支持。首先，PLC1P与哺乳动物PLC-gamma最相似，后者也会转导氧化应激信号。另外，人类细胞周期蛋白C也因人和酵母细胞的压力而被破坏。该提案结合了酵母中可用的强大遗传和分子工具，以剖析氧化应激信号通路并确定其核靶标。我们将我们的遗传系统与微阵列分析相结合，以查明基因，其表达对于响应ROS的生存力至关重要。最后，这些基因将在酵母和人类细胞中被异位激活或删除，以确定它们在药物敏感性或抗性中的作用。