MECHANISMS OF LUNG ADENOMA FORMATION

肺腺瘤形成机制

• 批准号: 3071528
• 负责人: ALVIN M MALKINSON
• 金额: $ 4.84万
• 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/3071528
• 关键词: antibody formation; butylated hydroxytoluene; chemical carcinogen; chemical carcinogenesis; cyclic AMP; gene expression; high performance liquid chromatography; lung neoplasms; neoplasm /cancer genetics; polyurethanes; 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被要求减轻沉重的教学负担，并允许全职 对下述项目的研究以及获得经验的时间 并将其应用于肺腺瘤。 通过 比较致癌物氨基甲酸乙酯的影响， 肺毒性和肿瘤促进剂，丁基羟基甲苯（BHT）， 对腺瘤形成具有不同易感性的小鼠品系，我们将 区分肿瘤特有的生化变化和 正常增殖反应的特征。 的细胞起源 尿烷诱发的A系成年小鼠腺瘤为2型 肺泡细胞，但腺细胞也可以从克拉拉细胞产生。 的影响 将确定腺瘤来源菌株、年龄和致癌物。 单个 在BALB小鼠中赋予对腺瘤的抗性的显性基因将是 用于区分尿烷的毒性作用和真正的肿瘤作用， 并将使用重组近交系小鼠绘制地图。 我们将确定 该基因是否阻止增生灶的形成或其进一步的 进展 用解剖的胚胎雏形进行移植研究 将决定这个基因是作用于上皮组织还是间质组织。 的 BHT增强腺瘤形成的机制将使用 分析BHT的灵敏分析技术，HPLC和GC/MS 体内和体外产生的代谢物。 毒性和促肿瘤作用 BHT的影响在近交系、种和器官之间不同。 通过 将各种系统中产生的代谢物与 BHT在该系统中的生理效应，我们希望能够清楚地识别 并区分其毒性和促肿瘤衍生物 化合物. 腺瘤cAMP受体结合肿瘤细胞的能力降低， 光亲和类似物，8-N3-cAMP，并且已经失去了cAMP 刺激自身磷酸化。 这种变化将在孤立的 2型细胞在癌变的早期阶段。 抗体将 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。 的 这种受体敏感性丧失的生理后果将是 在2型细胞中通过监测cAMP刺激 内源性蛋白磷酸化。 活性之间的关联 不同菌株中Ca~（++）和磷脂激活的蛋白激酶 并且这些菌株对腺瘤诱导的敏感性将是 由于这种激酶可能参与进展， 启动的细胞。 环GMP的光亲和类似物，8-N3-（32 p）cGMP， 将用于监测由环鸟苷酸激活的激酶， 在正常发育和再生肺细胞分裂期间。