反义调控DNA甲基转移酶3b基因对人胆管癌细胞QBC939生长的影响

目的观察转染反义DNMT3b基因真核表达质粒对人胆管癌细胞QBC939生长的影响，初步探讨DNMT3b基因在胆管癌发生中的作用。方法构建反义DNMT3b基因真核表达质粒，用脂质体介导法将其转人人胆管癌细胞株QBC939；Western blot检测转染前后DNMT3b蛋白表达的变化；MTT法和软琼脂克隆形成试验观察细胞的生长增殖能力；流式细胞术观察细胞生长周期及凋亡率的变化。结果转染反义基因能使DNMT3b蛋白表达水平降低；转染反义DNMT3b基因不能抑制QBC939的生长曲线，对其软琼脂克隆形成率亦无影响（P=0．717）；转染反义DNMT3b基因不能改变QBC939的细胞周期和促进细胞凋亡（P=0．089）。结论转染反义DNMT3b基因真核表达质粒可下调DNMT3b在QBC939细胞中的表达水平，但对QBC939的生长和增殖无影响，也不能改变QBC939的细胞周期和促进细胞凋亡的发生。

Effect of down-regulating DNMT3b expression by transfection with antisense gene on the growth of human cholangiocarcinoma cell line QBC939

Objective To study the effect of transfection with antisense DNMT3b gene eukaryotic expression plasmid on the growth of human cholangiocarcinoma cell line QBC939,and to explore the role of DNMT3b in the cholangiocarcinoma tumorigenesis.Methods The constructed antisense DNMT3b gene eukaryotic expression plasmid was transfected into QBC939 cells using liposome.The expression level of DNMT3b protein was detected by Western blot after stable transfection.The growth curves of transfected cells and un-transfected cells were observed by MTT method respectively.The cell proliferation ability was also observed by the test of colony formation in soft agar.The alterations of the cell cycle and the apoptosis rate were detected by FCM.Results Following the transfection,the protein level of DNMT3b decreased significantly;transfection with antisense DNMT3b gene eukaryotic expression plasmid did not affect the cell growth curve of QBC939,and did not decrease the cell colony formation rate(P=0.717);transfection with antisense DNMT3b gene also did not result in cell cycle alterations or induce cell apoptosis(P=0.089).Conclusions Transfection with antisense DNMT3b gene eukaryotic expression plasmid can down-regulate the expression level of DNMT3b in QBC939.It can not affect the growth and proliferation of human cholangiocarcinoma cell line QBC939,nor alter the cell cycle and induce cell apoptosis.