HYPOXIA STRESS GENES IN VITRO AND IN SOLID TUMORS

肿瘤血液供应不足建立了氧、葡萄糖、 生长调节剂和其他物质沿着扩散路径辐射 来自血管。 这些压力环境代表了生理 肿瘤组织与正常组织的差异。 SRI 研究人员表明 人类和啮齿动物肿瘤细胞的缺氧应激会诱导合成 一组称为氧调节蛋白或 ORP 的蛋白质。 它是 假设受缺氧应激调节的基因很重要 恶性进展的参与者。 为了研究这个假设， SRI提出测量肿瘤组织中特定ORP的表达 并开发一个模型来测试 ORP 表达关系 对治疗有抵抗力。 该信息将允许创建 确定某些人类预后和治疗的新策略 癌症。 将使用两种方法来识别肿瘤组织的缺氧区域 （FaDu、SQ-20B 和 A431 人鳞状癌细胞）并建立 与 ORP 表达的相关性： (1) 氟化抗体 生物还原药物将用作阳性对照以可视化缺氧 体外肿瘤模型中的细胞，以及所选 ORP 的表达（例如， 血红素加氧酶-1 [HO-1; ORP 33]，金属硫蛋白 IIA [MT-IIA； ORP 7]，和 血管内皮生长因子[VEGF]）将通过原位检测 杂交和免疫组织化学； (2) 类似的实验将 可以用人类肿瘤异种移植物进行。 SRI 的初步研究表明，人 MT-IIA 是一种合适的 ORP 研究缺氧引起的治疗抵抗的发展 和复氧。 我们将使用瞬时和稳定的转染子 人鳞状癌细胞创建多细胞肿瘤球体 用于研究 (1) 缺氧响应 MT-IIA 5'-调节的模型 (2)MT-IIA表达对顺铂耐药的影响。 这些实验旨在创建体外肿瘤模型 人 MT-IIA (ORP 7) 5'-调节区和编码序列 低氧和葡萄糖应激对临床的影响研究 相关缺氧应激蛋白。 该模型将提供一个测试系统 用于与缺氧和复氧相关的诱导耐药性。

Deficiencies in tumor blood supply establish gradients of oxygen, glucose, growth regulators, and other substances along diffusion paths radiating from blood vessels. These stress environments represent physiological differences between tumor and normal tissue. SRI researchers have shown that hypoxic stress in human and rodent tumor cells induces the synthesis of a set of proteins called oxygen regulated proteins or ORPs. It is hypothesized that genes regulated by hypoxic stress are important participants in malignant progression. To investigate this hypothesis, SRI proposes to measure the expression of specific ORPs in tumor tissue and to develop a model to test the relationship of expression of an ORP with resistance to therapy. This information will permit the creation of novel strategies for determining the prognosis and treatment of some human cancers. Two approaches will be used to identify hypoxic regions of tumor tissue (FaDu, SQ-20B, and A431 human squamous carcinoma cells) and establish correlations with ORP expression: (1) antibodies to a fluorinated bioreductive drug will be used as a positive control to visualize hypoxic cells in tumor models in vitro, and the expression of selected ORPs (e.g., heme oxygenase-1 [HO-1; ORP 33], metallothionein IIA [MT-IIA; ORP 7], and vascular endothelial growth factor [VEGF]) will be detected by in situ hybridization and immunohistochemistry; and (2) similar experiments will be performed with human tumor xenografts. SRI's preliminary studies indicate that human MT-IIA is a suitable ORP for investigating the development of therapeutic resistance caused by hypoxia and reoxygenation. We will use transient and stable transfectants of human squamous carcinoma cells to create multicellular tumor spheroid models for investigating (1) a hypoxia-responsive MT-IIA 5'-regulatory region and (2) the effect of MT-IIA expression on resistance to cisplatin. These experiments are directed toward creating an in vitro tumor model of the human MT-IIA (ORP 7) 5'-regulatory region and coding sequence for investigation of the effects of hypoxic and glucose stress on a clinically relevant hypoxic stress protein. This model will provide a test system for inducible drug resistance associated with hypoxia and reoxygenation.