摘要
目的:通过建立小鼠模型,模拟并观察慢性阻塞性肺疾病(chronic obstructive pulmonary disease,COPD)慢性炎症环境对肺癌生长及转移的影响,检测并分析相关炎症细胞因子IL-1β,IL-6,TNF-α和IL-8在这一过程中发挥的作用,并探讨可能相关的信号通路。方法:选用5~8周龄(20~25 g)的雄性C57/BL6小鼠,用熏烟加气道滴注LPS的方法构建COPD模型,在COPD模型的基础上注射Lewis肺癌(Lewis lung cancer,LLC)细胞建立COPD合并肺癌小鼠模型;在COPD合并肺癌小鼠模型的基础上通过注射甲强龙控制慢性炎症,以建立经甲强龙治疗的COPD合并肺癌小鼠模型。观察并比较经甲强龙治疗的COPD合并肺癌模型小鼠、未经甲强龙治疗的COPD合并肺癌模型小鼠以及单纯肺癌模型小鼠3组肿瘤的生长体积及转移灶数量。以正常小鼠作为对照,用ELISA检测并比较单纯COPD小鼠、单纯肺癌小鼠、COPD合并肺癌小鼠、经甲强龙治疗的COPD合并肺癌小鼠血清IL-1β,IL-6,TNF-α,IL-8水平,用Real-time PCR的方法检测这5组小鼠肺组织内上述炎症细胞因子相应的mRNA的表达水平,并用Western印迹检测这5组小鼠肺组织内一些相关信号通路上的信号分子Stat3,ERK1/2,NF-κB,IκBα的活化比例。结果:与单纯肺癌小鼠相比,COPD合并肺癌小鼠的中位生存期较短,肺部病灶的体积较大,肺部转移灶数量较多,差异有统计学意义(P<0.05);而经甲强龙治疗的COPD合并肺癌小鼠,这些改变都较未治疗组有所下降,差异有统计学意义(P<0.05)。IL-1β,IL-6,IL-8在COPD合并肺癌肺组织及血清中的表达比例均较单纯肺癌组及单纯COPD组上调,差异有统计学意义(P<0.05),其中IL-6在COPD合并肺癌小鼠肺组织内的表达水平较单纯肺癌及单纯COPD小鼠增加2倍以上,且较正常对照组小鼠增加5倍以上,上调比例较其他3种炎症细胞因子大,而经甲强龙治疗的小鼠这些炎症细胞因子的水平均有所下降,差异有统计学意义(P<0.05)。COPD合并肺癌小鼠肺组织内相关的信号分子Stat3,NF-κB,IκBα的活化比例高于正常对照组、单纯肺癌组及单纯COPD组,差异有统计学意义(P<0.05),经甲强龙治疗的COPD合并肺癌小鼠肺组织匀浆内这3种信号分子的活化比例均较未治疗组有不同程度的下降,差异有统计学意义(P<0.05)。结论:COPD慢性炎症环境可促进肺癌的生长及转移,从而缩短肺癌小鼠的生存期,使用甲强龙控制炎症反应后可抑制这种促进作用;IL-6,IL-8可能参与COPD慢性炎症环境对肺癌生长及转移的促进过程。
Objective： To observe the influence of chronic obstructive pulmonary disease（COPD）-like chronic inflammation on the growth and metastasis of lung cancer through a mouse model, analyze the role of IL-1β, IL-6, TNF-α and IL-8 in the progression, and to find the probable signaling pathway. Methods： We selected male C57/BL6 mice aged 5–8 weeks, weighted 20–25 g to establish a COPD-like mouse model by smoking and instilled intratracheally with LPS. Lewis lung cancer cells（LLC） were implanted by directly puncturing through the skin and intercostal space into the lung to establish a lung cancer model, and implanted into the lung of COPD-like mouse to establish a COPD combined with lung cancer model. Methylprednisolone was injected into COPD combined with lung cancer model to establish a methylprednisolone-treated model. We observed and compared the tumor size and metastases number of COPD-lung cancer mouse model, lung cancer mouse model and methylprednisolonetreated COPD-lung cancer mouse model. We detected the levels of IL-1β, IL-6, IL-8, TNF-α in serum by ELISA, and the expression of their m RNA in lung using real-time PCR in each group. And we also detected the expression of some probable signal molecule（Stat3, ERK1/2, NF-κB, and IκBα） in the lung of these 5 mice groups to find out the relative signaling pathway involved in the promoting process of chronic inflammation in COPD on the growth and metastasis of lung cancer. Results： Compared with lung cancer mice, the mice with lung cancer combined COPD had shorter median survival times, larger volumes of tumor nudes, and larger numbers of metastases, but if they were treated with methylprednisolone, all these changes come down, the differences were all statistically significant（P〈0.05）. The levels of IL-1β, IL-6, IL-8 in the COPD-lung cancer mice serum were significantly higher than COPD mice without lung cancer and lung cancer mice without COPD（P〈0.05）, and IL-6 increased much more sharply than other inflammatory cytokines in COPD-lung cancer mice, which increased about 2 times more than COPD mice and lung cancer mice, and 5 times more than control mice. In methylprednisolone-treated COPD-lung cancer mice, levels of all the inflammatory cytokines decreased. The activation ratios of Stat3, NF-κB, IκBα were significantly higher in COPD-lung cancer mice than control mice, COPD mice, and lung cancer mice（P〈0.05）, and significantly lower in methylprednisolone-treated COPD-lung cancer mice than untreated（P〈0.05）. Conclusion： The chronic inflammatory environment can promote the growth and metastasis of lung cancer, and then shorten the survival of lung cancer in our mouse model, controlling the inflammation using methylprednisolone can inhibit the promoting effect of COPD on lung cancer. IL-6 and IL-8 play roles in the promoting effect of chronic inflammation in COPD mice on the growth and metastasis of lung cancer.
出处
《临床与病理杂志》
2017年第11期2323-2331,共9页
Journal of Clinical and Pathological Research
关键词
慢性阻塞性肺疾病
肺癌
小鼠模型
肿瘤生长转移
炎症细胞因子
Lewis lung cancer cells（LLC）
lung cancer model
COPD
chronic inflammation
median survival times
tumor nudes
