MECHANISMS OF LUNG ADENOMA FORMATION

肺腺瘤形成机制

• 批准号: 3071531
• 负责人: ALVIN M MALKINSON
• 金额: $ 4.96万
• 依托单位: UNIVERSITY OF COLORADO
• 依托单位国家: 美国
• 财政年份: 1984
• 资助国家: 美国
• 起止时间: 1984-09-01 至 1989-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3071531
• 关键词: antibody formation; butylated hydroxytoluene; chemical carcinogen; chemical carcinogenesis; cyclic AMP; gene expression; high performance liquid chromatography; laboratory mouse; laboratory rat; lung neoplasms; neoplasm /cancer genetics; polyurethanes; protein kinase A; radiotracer

An RCDA is requested to relieve a heavy teaching load, and allow full-time research on the project described below as well as time to gain experience in recombinant DNA technology and apply this to lung adenomas. By comparing the effects of the carcinogen, urethane, with those of the lung-toxic and tumor promoting agent, butylated hydroxytoluene (BHT), in mouse strains with different susceptibilities to adenoma formation, we will distinguish biochemical changes unique to neoplasia from those characteristic of a normal proliferative response. The cellular origin of the adenomas induced by urethane in adult Strain A mice is the Type 2 alveolar cell, but adenonas can also arise from Clara cells. The effect of strain, age and carcinogen on adenoma origin will be determined. A single dominant gene in BALB mice which confers resistance to adenomas will be used to differentiate toxic effects of urethane from truly neoplastic ones, and will be mapped using recombinant inbred mice. We will determine whether this gene prevents formation of hyperplastic foci or their further progression. Transplantation studies with dissected embryonic rudiments will determine if this gene acts on epithelial or mesenchymal tissue. The mechanisms by which BHT enhances adenoma formation will be studied using the sensitive analytical techniques, HPLC and GC/MS, to analyze the BHT metabolites produced in vivo and in vitro. The toxic and tumor promoting effects of BHT vary between inbred strains, species and organs. By comparing the metabolites produced in a variety of systems with the physiological effects of BHT in that system, we hope to clearly identify and distinguish between the toxic and tumor promoting derivations of this compound. Adenoma cAMP receptors have a decreased ability to bind the photoaffinity analog, 8-N3-cAMP, and have lost the ability for cAMP to stimulate autophosphorylation. Such changes will be looked for in isolated Type 2 cells at earlier stages of carcinogenesis. Antibodies will be prepared against the R-subunits of cAMP-dependent protein kinases, and used to determine changes in subunit concentrations and turnover rates. The physiological consequence of this loss of receptor sensitivity will be studied in Type 2 cells by monitoring the ability of cAMP to stimulate endogenous protein phosphorylation. Correlation between the activity of protein kinases activated by Ca++ and phospholipids in different strains and the susceptibility of these strains to adenoma induction will be thoroughly investigated, since this kinase may be involved in progression of initiated cells. A photoaffinity analog of cyclic GMP, 8-N3-(32p)cGMP, will be used to monitor the kinases activated by cyclic GMP, which change during normal development and regenerative lung cell division.

RCDA被要求减轻繁重的教学负担，并允许全职 对下述项目的研究以及获得经验的时间 重组DNA技术并将其应用于肺腺瘤。 经过 比较致癌物聚氨酯的影响 肺毒性和肿瘤促进剂丁基羟基甲苯 (BHT) 具有不同腺瘤形成易感性的小鼠品系，我们将 区分肿瘤特有的生化变化和其他生化变化 正常增殖反应的特征。 细胞起源 成年 A 品系小鼠中由尿烷诱发的腺瘤为 2 型 肺泡细胞，但腺细胞也可以由克拉拉细胞产生。 的效果 将确定腺瘤起源的菌株、年龄和致癌物质。 单个 BALB小鼠中赋予腺瘤抵抗力的显性基因将是 用于区分聚氨酯的毒性作用和真正的肿瘤性毒性作用， 并将使用重组近交小鼠进行绘图。 我们将确定 该基因是否可以阻止增生灶的形成或其进一步的形成 进展。 解剖胚胎雏形的移植研究 将确定该基因是否作用于上皮组织或间质组织。 这 将使用以下方法研究 BHT 增强腺瘤形成的机制 使用灵敏的分析技术 HPLC 和 GC/MS 来分析 BHT 体内和体外产生的代谢物。 毒性和促肿瘤作用 BHT 的影响因近交系、物种和器官而异。 经过 将各种系统中产生的代谢物与 BHT 在该系统中的生理效应，我们希望清楚地识别 并区分该衍生物的毒性和促肿瘤作用 化合物。 腺瘤 cAMP 受体结合能力下降 光亲和类似物 8-N3-cAMP，并且已经失去了 cAMP 的能力 刺激自身磷酸化。 此类变化将在孤立的情况下寻找 处于癌变早期阶段的 2 型细胞。 抗体将会 针对 cAMP 依赖性蛋白激酶的 R 亚基制备，并使用 以确定亚基浓度和周转率的变化。 这 受体敏感性丧失的生理后果将是 通过监测 cAMP 刺激的能力，在 2 型细胞中进行了研究 内源性蛋白质磷酸化。 活性之间的相关性 不同菌株中 Ca++ 和磷脂激活的蛋白激酶 这些菌株对腺瘤诱导的敏感性将是 彻底研究，因为该激酶可能参与进展 启动的细胞。 环 GMP 的光亲和类似物，8-N3-(32p)cGMP， 将用于监测由环 GMP 激活的激酶，这些激酶会改变 在正常发育和再生性肺细胞分裂期间。