IL-18促进肺癌细胞转移的功能鉴定  

Function of IL-18 in promoting metastasis of lung cancer

作　　者：蒋代凤[1] 刘万里[1] 陆应麟[2] 邱宗荫[3] 贺福初[1] 

机构地区：[1]北京军事医学科学院放射医学研究所,100850400016 [2]北京军事医学科学院基础医学研究所 [3]重庆医科大学检验系

出　　处：《中华肿瘤杂志》2003年第4期348-352,共5页Chinese Journal of Oncology

基　　金：国家重点基础研究资助项目 (G2 0 0 1CB5 10 2 0 1;G19980 5 12 13 ) ;国家自然科学基金资助项目 ( 3 973 0 2 700;3 9990 60 0 )

摘　　要：目的　探讨IL 18是否具有促进肺癌细胞转移的功能以及通过何种途径发挥作用。方法　以人肺巨细胞癌高、低转移株为肿瘤转移的研究模型 ,采用Westernblot和半定量RT PCR结合Northernblot法检测IL 18蛋白或mRNA在肺巨细胞癌高、低转移株的差异表达 ;随后采用基因转染技术将IL 18的正义或反义表达质粒分别转染肺巨细胞癌低或高转移株 ,比较IL 18稳定转染细胞转移表型的改变。采用MICS系统检测稳定转染细胞体外迁移和侵袭能力的改变 ,采用Westernblot法检测稳定转染细胞转移表型相关指标的改变 ,从而确定IL 18通过何种途径促进肺癌细胞转移。结果由于IL 18蛋白和mRNA仅在肺巨细胞癌高转移株检测到 ,因此 ,将IL 18正义表达质粒转染肺巨细胞癌低转移株后 ,可检测到IL 18融合蛋白的表达 ,且稳定转染细胞出现了细胞体外迁移能力的显著上调和上皮细胞间黏附分子E cadherin蛋白的显著下调 ;相反 ,将IL 18反义表达质粒转染肺巨细胞癌高转移株后 ,可检测到内源性IL 18蛋白和mRNA水平的下调 ,且稳定转染细胞出现了细胞体外侵袭能力的显著下调和E cadherin蛋白的显著上调。结论　IL 18可能通过抑制上皮细胞间黏附分子E cadherin蛋白的表达来促进肺癌细胞的转移。Objective To study the function of IL 18 in promoting metastasis of lung cancer. Methods The differential expression of IL 18 protein or mRNA level between highly and poorly metastatic sublines of human lung giant cell carcinoma metastatic model was detected by Western blot, semi quantitative RT PCR and northern blot analysis. The poorly metastatic PLA801C subline or highly metastatic PLA801D subline was transfected with constructed IL 18 sense or IL 18 antisense expressed plasmid by lipofectamine stable transfection technique. The metastasis related effect mediated by IL 18, the metastatic phenotype differences, cell motility and cell invasion potential in vitro determined by MICS system and the expression level of metastasis associated biomarkers detected by Western blot analysis, were compared between IL 18 stably transfectants and mock control, i.e. between PLA801C/IL 18(S) and PLA801C/pcDNA3.1, or between PLA801D/ IL 18(As) and PLA801D/pcDNA3. Results IL 18 was only present in highly metastatic PLA801D subline at either protein or mRNA level, which implied that IL 18 might play a role in promoting metastasis of lung cancer. After IL 18 sense expressed plasmid was transfected into poorly metastatic PLA801C subline, IL 18 fused protein with myc tag detected by Western blot analysis using either IL 18 or myc tag monoclonal antibody. In addition, cell motility ability in vitro was significantly increased about 3 times and E cadherin protein was significantly down regulated at about 50% in PLA801C/IL 18(S) transfectants compared with mock control. While IL 18 expressed plasmid was transfected into highly metastatic PLA801D subline, IL 18 protein and mRNA were simultaneously decreased by 30%. In addition, cell invasion ability in vitro was significantly decreased at about 75% and E cadherin protein was significantly up regulated in PLA801D/IL 18(As) transfectants compared with mock control.Conclusion IL 18 might play a role in enhancing tumor metastasis of lung cancer by down r

关 键 词：肺癌 肿瘤转移 白细胞介素-18 基因转染 E-CADHERIN蛋白 

分 类 号：R734.2[医药卫生—肿瘤]