肺泡上皮细胞间质转化对肺癌细胞转移影响的研究  

Effect of epithelial-mesenchymal transition of alveolar epithelial cells on metastasis of lung cancer

作　　者：黄振杰[1] 郑金旭[2] 汤艳[2] 蔡文华[1] 曾彤华[1] 陈文海[1] 梁海青[1] 

机构地区：[1]北海市人民医院呼吸科,广西北海536000 [2]江苏大学附属医院呼吸科,江苏镇江212001

出　　处：《中华肿瘤防治杂志》2011年第16期1230-1234,共5页Chinese Journal of Cancer Prevention and Treatment

基　　金：卫生部科研项目(wkj2006-2-026);江苏省"333工程"资助项目(苏人才办2007-16-09)

摘　　要：目的:通过以TGF-β1诱导肺腺癌细胞系A549细胞出现上皮细胞-间质细胞转化(EMT),并探讨EMT过程的信号转导途径及肺EMT与肺癌转移之间的关系。方法:体外培养A549细胞,以TGF-β1进行干预,收集不同时段的细胞,用荧光实时定量PCR检测上皮及间质细胞标志的mRNA表达,蛋白质印迹法检测上皮及间质细胞标志的蛋白表达、信号转导蛋白P-Smad2/3、Snail1和Snail2的表达及基质金属蛋白酶MMP-2和MMP-9的表达,通过倒置相差显微镜观察肺EMT过程中细胞形态学的变化。结果:TGF-β1干预后,A549细胞上皮细胞标志(E-cad、CK19)的mRNA和蛋白表达下调(P<0.01),间质细胞标志(Vimentin、α-SMA)的mRNA和蛋白表达上调,P<0.05;信号转导蛋白P-Smad 2/3和Snail1上调(P<0.05),Snail2弱表达,P>0.05;基质金属蛋白酶MMP-2上调(P<0.05),MMP-9弱表达,P>0.05;倒置相差显微镜观察到TGF-β1干预后A549细胞由鹅卵石状变为梭形,形态如同肌纤维母细胞。结论:在TGF-β1的诱导下,肺腺癌细胞从上皮细胞向间质细胞转化,其与Smad 2/3和Snail1信号转导途径相关,同时伴随了MMP-2的表达增强,因此肺泡上皮细胞向间质细胞的转化可能通过改变细胞形态学和增加基质金属蛋白酶的表达,增强了癌细胞的侵袭性,促进肺癌的转移。而通过阻断肺癌细胞的EMT过程及其信号转导途径有可能抑制肺癌的转移。OBJECTIVE：By inducing epithelial-mesenchymal transition（EMT） of adenocarcinoma cells of lung A549 with transforming growth factorβ1（TGF-β1）and investigating its signalling pathway,to explore the relation between EMT of alveolar epithelial cells and metastasis of lung cancer.METHODS： A549 cells cultured in vitro were treated by TGF-β1,then harvested at different time points to assay the expression of the markers of epithelial cell and mesenchymal cell by Real-time PCR and Western blot,to assay the expression of signal transducers P-Smad 2/3,Snail1,Snail2 and matrix metalloproteinases MMP-2,MMP-9 by Western blot.Cellular morphology changes in EMT of alveolar epithelial cells were observed by phase-contrast microscope.RESULTS： After A549 cells being treated by TGF-β1,mRNA and protein expression of epithelial markers（E-cad and CK19） was down-regulated（P0.01） and that of mesenchymocyte markers（Vimentin and α-SMA） up-regulated（P0.05）.Signal transducers P-Smad 2/3 and Snail1 were up-regulated（P0.05） in Western blot,with a weak expression of Snail2（P0.05）.Matrix metalloproteinase MMP-2 was also up-regulated（P0.05）,with a weak expression of MMP-9（P0.05）.A549 cells were observed by inverted phase contrast microscope to turn from pebble shape to fusiform shape,a myofibroblast-like morphology.CONCLUSIONS： TGF-β1 can induce EMT of adenocarcinoma cells of lung in vitro,associated with signalling pathway Smad 2/3 and Snail1,apart from Snail2.Meanwhile,this course accompanied an increased expresssion of MMP-2.EMT of alveolar epithelial cells may strengthen infestation of cancer cell and promote metastasis of lung cancer by changeing cellular morphology and increasing expresssion of matrix metalloproteinases.It may restrain metastasis of lung cancer to block the EMT process and its signalling pathway of lung cancer cell.

关 键 词：A549细胞 转化生长因子Β1 上皮细胞间质转化 肺肿瘤 

分 类 号：R734.2[医药卫生—肿瘤]