TUMOR PROMOTERS & PROTEIN KINASE C IN CANCER METASTASIS

肿瘤促进剂

• 批准号: 3458826
• 负责人: RAYUDU GOPALAKRISHNA
• 金额: $ 9.38万
• 依托单位: UNIVERSITY OF CALIFORNIA LOS ANGELES
• 依托单位国家: 美国
• 财政年份: 1988
• 资助国家: 美国
• 起止时间: 1988-05-01 至 1993-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3458826
• 关键词: anticoagulants; antineoplastics; basement membrane; binding proteins; calcium; cell adhesion; diacylglycerols; enzyme mechanism; histochemistry /cytochemistry; laboratory mouse; lung neoplasms; melanoma; membrane activity; membrane proteins; metastasis; phorbols; phosphorylation; protein kinase C; proteolysis; radiotracer; tumor promoters; vascular endothelium

Tumor promoter phorbol esters, and cellular regulators which elevate intracellular diacylglycerol, induce protein kinase C association to the plasma membrane and thereby influence various cellular functions including cell adhesion and exocytosis. These Ca2+-regulated functions play key roles in hematogenous metastasis. Our original observations showing a strong correlation between the levels of membrane-bound protein kinase C activity and metastatic ability in three well characterized phenotypically stable sublines of B16 murine melanoma exhibiting low (F1), intermediate (BL6) and high (F10) metastatic behaviour prompted the present proposal designed to investigate the role of membrane-bound protein kinase C in hematogenous metastasis. The reasons why membrane-bound protein kinase C activity is low in the F1 subline compared F10 will be tested. Based on observations that 12-0 tetradecanoylphorbol-13-acetate (TPA) (1 h)-treatment stimulates membrane-association of protein kinase C and increases metastasis whereas TPA (24 h) treatment inactivates protein kinase C and decreases metastasis, this study will investigate the effects of physiological regulators and pharmacological agents, which modulate membrane association of protein kinase C, on hematogenous metastasis. Metastasis will be evaluated by counting the number of pulmonary nodules appearing 3 weeks after tail vein injection of treated cells. These cells will also be tested for their in vitro attachment to endothelial monolayers and basement membranes and their early (3 h) in vivo pulmonary retention to assess alterations in cell adhesion mediated by protein kinase C. The study will identify the membrane target proteins phosphorylated by protein kinase C and examine whether their affinity for endothelium and basement membranes is altered. Finally, the mechanism of protein kinase C inactivation with prolonged TPA treatment will be addressed with specific attention placed on the roles of proteolytic inactivation by calpain (Ca2+-activated protease) and oxidative inactivation by reactive oxygen species. Certain agents including anticancer drugs that are known to generate oxygen free radicals will be tested for their ability to inactivate protein kinase C and inhibit metastasis. This study also will evaluate the additional role of tumor promoters in the hematogenous spread of cancer.

肿瘤启动子Phorbol酯和细胞调节剂 升高细胞内二酰基甘油，诱导蛋白激酶C 与质膜的关联，从而影响各种 细胞功能，包括细胞粘附和胞吐作用。 这些 CA2+调节功能在血源中起关键作用 转移。 我们最初的观察结果表明 膜结合蛋白激酶水平之间的相关性 C活性和转移能力以三个良好的特征 B16鼠黑色素瘤表现出表型稳定的肌表型 低（F1），中级（BL6）和高（F10）转移行为 促使目前的提案旨在调查 膜结合的蛋白激酶C在血源转移中。 膜结合蛋白激酶C活性低的原因 在F1 Subline中，将测试F10。 基于 观察到12-0 tetradecanoylphorbol-13-乙酸酯（TPA）（1 h） - 处理刺激蛋白激酶的膜缔合 C并增加转移，而TPA（24小时）处理 灭活蛋白激酶C并减少转移，这项研究 将研究生理调节剂和 药理剂，调节膜关联 蛋白激酶C，在血源转移上。 转移会 通过计算出现的肺结核的数量来评估 尾静脉注射后的细胞后3周。 这些细胞会 还可以在体外附着在内皮上进行测试 单层和地下膜及其早期（3 h）体内 肺部保留以评估细胞粘附的改变 由蛋白激酶C介导的C.该研究将确定 蛋白激酶C和 检查它们对内皮和地下室的亲和力是否 膜发生了变化。 最后，蛋白激酶C的机制 长时间的TPA治疗将与 对蛋白水解失活的作用的具体关注 通过钙蛋白酶（Ca2+活化的蛋白酶）和氧化失活 活性氧。 包括抗癌在内的某些代理商 已知会产生氧气自由基的药物将是 测试了它们灭活蛋白激酶C并抑制的能力 转移。 这项研究还将评估 癌症肿瘤启动子的癌症。