Prevention of Lung Cancer Growth by Angiotensin-(1-7)

通过血管紧张素-(1-7)预防肺癌生长

• 批准号: 6770194
• 负责人: Ann Ann Tallant
• 金额: $ 7.18万
• 依托单位: WAKE FOREST UNIVERSITY HEALTH SCIENCES
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-07-01 至 2006-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6770194
• 关键词: angiotensin receptor; angiotensins; apoptosis; cell cycle; cell line; cell proliferation; cell transformation; chemoprevention; flow cytometry; growth inhibitors; laboratory mouse; lung neoplasms; mitogen activated protein kinase; neoplastic growth; nucleic acid purification; polymerase chain reaction; receptor coupling; western blottings

DESCRIPTION (provided by applicant): Lung cancer is a leading cause of death in both men and women, accounting for approximately 160,000 deaths annually in the United States with over 1,000,000 new cases of lung cancer worldwide. Despite a number of clinical trials testing various compounds as chemopreventive agents, none were effective in reducing the risk of lung cancer. However, treatment of hypertensive patients with angiotensin converting enzyme (ACE) inhibitors reduced the risk of cancer, especially lung cancer. Inhibition of ACE activity decreases angiotensin II (Ang II) and increases the levels of both bradykinin and angiotensin-(1-7) [Ang-(1-7)]. We showed that Ang-(1-7) reduces vascular growth in vitro and prevents neointimal formation in vivo. More importantly, our preliminary studies showed that Ang-(1-7) markedly inhibits the growth of human lung cancer cells and reduces tumor growth in vivo. Thus, we propose that the antiproliferative response to Ang-(1-7) extends beyond its effects on vascular cells and that Ang-(1-7) inhibits the growth of cancer cells. The studies outlined in this application are designed to determine whether Ang-(1-7) inhibits the proliferation of human lung cancer cells and identify the molecular mechanisms involved in this regulation. Established cell lines of human lung carcinomas will be examined for growth inhibition following treatment with various doses of Ang-(1-7). Attenuation of cell growth will be assessed by 3H-thymidine incorporation into proliferating cells, reductions in cell number using the modified MTT assay, and cell cycle analysis by flow cytometry. The specificity of the antiproliferative response to Ang-(1-7) will be determined using other angiotensin peptides and receptor antagonists. The attenuation of lung cancer cell growth by Ang-(1-7) will be examined in mice with chemically-induced lung tumors, to demonstrate that Ang-(1-7) prevents or reduces lung tumor formation in vivo. Gene array analysis identified candidate genes regulated by Ang-(1-7) following mitogen stimulation of human lung cancer cells, including up-regulation of genes encoding tumor suppressors and cell death signals and downregulation of genes encoding signaling pathways stimulating cell growth. Regulation of specific genes and proteins by Ang-(1-7) will be assessed by reverse transcriptase-polymerase chain reaction (RT-PCR) assays and Western blot hybridization, to determine their role in Ang-(1-7)-mediated lung cancer cell growth inhibition. The results of these studies will determine whether Ang-(1-7) effectively attenuates the proliferation of human lung cancer cells and identify the cellular pathways involved in the inhibitory response. The ultimate goal of this work is to determine whether administration of Ang-(1-7) or agents, which increase circulating Ang-(1-7) is an effective chemopreventive treatment for lung cancers.

描述（由申请人提供）： 肺癌是男性和女性的主要死亡原因，在美国，每年约有16万人死亡，全球有100万例新的肺癌病例。尽管许多临床试验测试了各种化合物作为化学预防剂，但没有一个可以有效降低肺癌的风险。然而，治疗高血压患者血管紧张素转化酶（ACE）抑制剂的治疗降低了癌症的风险，尤其是肺癌。 ACE活性的抑制会降低血管紧张素II（ANG II），并增加了心动激肽和血管紧张素 - （1-7）[Ang-（1-7）]的水平。我们表明，Ang-（1-7）在体外减少了血管生长，并防止体内新内膜形成。更重要的是，我们的初步研究表明，ANG-（1-7）显着抑制人类肺癌细胞的生长并减少体内肿瘤的生长。因此，我们建议对Ang-（1-7）的抗增殖反应超出其对血管细胞的影响，并且ANG-（1-7）抑制了癌细胞的生长。该应用中概述的研究旨在确定ANG-（1-7）是否抑制了人类肺癌细胞的增殖并确定所涉及的该调节的分子机制。在用各种剂量的ANG-（1-7）治疗后，将检查已建立的人肺癌的细胞系以进行生长抑制。细胞生长的衰减将通过掺入增殖细胞中的3H-胸苷评估，使用改良的MTT分析减少细胞数，以及通过流式细胞仪进行细胞周期分析。使用其他血管紧张素肽和受体拮抗剂来确定对Ang-（1-7）抗增殖反应的特异性。在化学诱导的肺部肿瘤的小鼠中将检查肺癌细胞生长的衰减，以证明Ang-（1-7）可防止或减少体内的肺肿瘤形成。基因阵列分析确定了促丝分裂原子刺激人类肺癌细胞后由Ang-（1-7）调节的候选基因，包括编码编码肿瘤抑制因子和细胞死亡信号的基因上调以及编码刺激细胞生长的信号通路的基因下调。通过逆转录酶 - 聚合酶链反应（RT-PCR）测定法和蛋白质印迹杂交对特定基因和蛋白质的调节，以确定其在Ang-（1-7）介导的肺癌细胞生长抑制中的作用。这些研究的结果将确定ANG-（1-7）是否有效地减弱了人类肺癌细胞的增殖并确定抑制反应中涉及的细胞途径。这项工作的最终目的是确定施用Ang-（1-7）或增加循环ANG-（1-7）的药物是对肺癌的有效化学预防治疗。