HYPOXIA STRESS MECHANISMS IN RADIATION AND CHEMOTHERAPY

放疗和化疗中的缺氧应激机制

• 批准号: 3460597
• 负责人: BRIAN J MURPHY
• 金额: $ 12.22万
• 依托单位: SRI INTERNATIONAL
• 依托单位国家: 美国
• 财政年份: 1992
• 资助国家: 美国
• 起止时间: 1992-08-15 至 1997-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3460597
• 关键词: DNA footprinting; SDS polyacrylamide gel electrophoresis; drug resistance; gel mobility shift assay; gene expression; genetic library; genetic promoter element; heme; hypoxia; immunocytochemistry; neoplasm /cancer chemotherapy; neoplasm /cancer radiation therapy; oxygen; oxygenases; polymerase chain reaction; protein biosynthesis; protein sequence; radiation sensitivity; reporter genes; site directed mutagenesis; stress proteins

Hypoxic stress induces changes at the molecular level that may be important for aspects of tumor progression and therapy. Specifically, the increased synthesis of a set of proteins termed oxygen-regulated proteins (ORPs) is induced by severe hypoxia. This induction and subsequent decay upon; reoxygenation are temporally correlated with the occurrence of drug resistance and radiosensitivity. The original group of five documented ORPs has now been expanded to include at least four other polypeptides. We have identified three ORPs, including heme oxygenase- 1 as an ORP 33 and ORPs 80 and 100 as glucose-regulated proteins 78 and 94, respectively. We also have data suggesting that hypoxia causes increased synthesis of the epidermal growth factor receptor. The ORPs are a unique group of stress proteins that are probably induced in response to disruption of cellular energy metabolism. The putative hypoxia-responsive elements of the ORP genes have not been investigated. Experiments are proposed here to study the mechanisms of induction and regulation of these hypoxia-induced stress proteins by using heme oxygenase-1 as a model. We believe that these studies will contribute to a better understanding of the genetic elements involved in the early events of cellular adaptation to hypoxia and may aid in the design of new strategies for therapeutic intervention. We also propose to isolate other prominent ORPs and to determine the identities of three of them by peptide sequencing or screening of cDNA libraries. Selection of specific ORPs for detailed studies will be determined by criteria outlined in Experimental Design and Methods. Purified proteins will also be used to prepare antibodies for visualizing the intracellular locations of the ORPs. We anticipate that these studies of ORP characterization and regulation will lead to a fundamental understanding of the role of hypoxic microenvironments in tumor biology.

缺氧应激会引起分子水平的变化，这可能很重要 用于肿瘤进展和治疗方面。 具体来说，增加的 一组称为氧调节蛋白（ORP）的蛋白质的合成是 严重缺氧所致。 这种感应和随后的衰减； 再氧合与药物的发生在时间上相关 电阻和放射敏感性。 最初的五人小组记录 ORP 现在已扩展到包括至少四种其他多肽。 我们已经确定了三种 ORP，包括作为 ORP 33 的血红素加氧酶- 1 和 ORP 80 和 100 分别为葡萄糖调节蛋白 78 和 94。 我们 还有数据表明缺氧会导致合成增加 表皮生长因子受体。 ORP 是一组独特的压力 可能是响应细胞破坏而诱导的蛋白质 能量代谢。 ORP 基因的假定缺氧反应元件尚未被证实。 调查了。 这里建议进行实验来研究其机制 通过使用诱导和调节这些缺氧诱导的应激蛋白 血红素加氧酶-1 作为模型。 我们相信这些研究将有助于 以便更好地了解参与早期发育的遗传因素 细胞适应缺氧的事件，可能有助于设计新的 治疗干预策略。 我们还建议隔离其他突出的 ORP 并确定 通过肽测序或 cDNA 筛选确定其中三个的身份 图书馆。 将选择具体的 ORP 进行详细研究 根据实验设计和方法中概述的标准确定。 纯化的蛋白质也将用于制备用于可视化的抗体 ORP 的细胞内位置。 我们预计这些研究 ORP 表征和调节的研究将导致根本性的 了解低氧微环境在肿瘤生物学中的作用。