BOMBESIN RECEPTORS MEDIATING METHADONE INDUCED APOPTOSIS

铃蟾肽受体介导美沙酮诱导的细胞凋亡

• 批准号: 6173953
• 负责人: RHODA MANECKJEE
• 金额: $ 18.47万
• 依托单位: OREGON HEALTH & SCIENCE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-07-08 至 2003-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6173953
• 关键词: 3T3 cells; ADP ribosylation; G protein; apoptosis; binding proteins; bombesin; drug receptors; drug screening /evaluation; enzyme activity; guanosine diphosphate; immunoregulation; lung neoplasms; methadone; mitogen activated protein kinase; neoplastic cell; neurotoxins; nicotine; nucleoside triphosphate; pertussis toxin; pharmacokinetics; phosphorylation; protein structure function; receptor binding; site directed mutagenesis; synthetic peptide

The therapeutic opioid drug methadone, that is generally used to treat cancer pain and opioid addiction, is also a potent inducer of apoptosis in human lung cancer cells, thus inhibiting their growth. This suggests a new therapeutic approach for the treatment of this cancer. However, in contrast to its central nervous system (CNS) actions, the apoptosis-inducing effects of methadone appear to be mediated through a non-opioid mechanism involving a dual- functioning bombesin receptor that is known to play a central role in the early events of pulmonary carcinogenesis. Methadone's effect is blocked in specific types of lung cancer cells that secrete high concentrations of bombesin and also by nicotine, suggesting the presence of an endogenous system coupling the apoptotic effects of nicotine, bombesin and opioids in these cells. This proposal aims to define the role of the bombesin receptor in this system, and determine whether distinct structural components are involved in the binding and functional coupling of the three ligands, with the aim of developing methadone ligands targeted towards tumor cells, and without CNS-associated toxic side effects. The specific aims of the proposal are (1) to identify the bombesin receptor type(s) involved in methadone's effects on the mitogen-activated protein (MAP) kinase signaling pathway, and apoptosis, using (a) Balb 3T3 cells transfected with the cloned bombesin receptor types (GRP, NMB and BRS-3), and (b) the different histologic types of lung cancer cells that differentially express these receptor types; (2) to determine whether nicotine acts- through this receptor type(s) to block methadone's effects; (3) to identify the structural features of the bombesin receptor involved in methadone and nicotine actions, using synthetic peptides and site-directed mutagenesis; (4) to determine the role of guanine nucleotide-binding proteins in the observed differential regulation of the bombesin receptor by methadone and bombesin. A clinical trial of methadone therapy for lung cancer patients is in progress, and these studies are expected to contribute significantly to our understanding of methadone's actions at the molecular level.

通常用于治疗癌症疼痛和阿片类药物成瘾的治疗阿片类药物美沙酮也是人类肺癌细胞凋亡的有效诱导剂，因此抑制了其生长。这暗示了一种治疗该癌症的新治疗方法。然而，与其中枢神经系统（CNS）作用相反，美沙酮的凋亡诱导作用似乎是通过涉及双功能bombesin受体的非阿片类药物机制介导的，该机制已知在肺癌发生的早期事件中起着核心作用。美沙酮的作用在特定类型的肺癌细胞中被阻止，这些肺癌细胞分泌高浓度的孟买和尼古丁，这表明存在这些细胞中尼古丁，bombesin和阿片类药物的凋亡作用的内源性系统。该提案旨在定义孟买受体在该系统中的作用，并确定三种配体的结合和功能偶联是否涉及三种配体的结合和功能偶联，目的是开发针对肿瘤细胞的美沙酮配体，并且没有CNSS SSS相关的毒性副作用。该提案的具体目的是（1），使用（a）BALB 3T3细胞鉴定白沙酮对促有丝分裂原激活蛋白（MAP）激酶信号通路和凋亡的影响的孟买受体类型，使用（a）BALB 3T3细胞用克隆的炸弹受体类型（GRP，NMB和nMB和BRENT and Carlung and Carlund and Cancelicic）构成（a）BALB 3T3细胞（a）BALB 3T3细胞（a）受体类型； （2）确定尼古丁是否通过这种受体类型作用以阻断美沙酮的作用； （3）使用合成肽和定向诱变，以确定与美沙酮和尼古丁作用有关的孟买受体的结构特征； （4）确定鸟嘌呤核苷酸结合蛋白在美沙酮和孟买观察到的bombesin受体的差异调节中的作用。美沙酮治疗对肺癌患者的临床试验正在进行中，预计这些研究将对我们对美沙酮在分子水平的作用的理解产生重大贡献。