反义DNA甲基转移酶1改变肝癌SMMC-7721细胞对肿瘤坏死因子相关凋亡诱导配体的敏感性及其机理的研究

Antisense DNMT1 gene fragment in the sensitivity change of SMMC-7721 cells to tumor necrosis factor related apoptosis inducing ligand and its mechanism

目的 观察转入反义DNA甲基转移酶 1(DNMT1)基因片段后的肝癌SMMC 772 1细胞对肿瘤坏死因子相关凋亡诱导配体 (TRAIL)的敏感性改变 ,初步阐明其机理。方法 台盼蓝排斥实验检测活细胞率 ;TUNEL法检测细胞凋亡率 ;流式细胞仪检测bcl 2、bax和bad蛋白的表达。结果 转入反义DNMT1基因片段的肝癌SMMC 772 1细胞与转入正义DNMT1基因片段和空载体的细胞相比 ,活细胞率显著降低 (P <0 .0 5,P <0 .0 1) ,凋亡率显著增高 (P <0 .0 5,P <0 .0 1)。流式细胞仪结果显示 ,转入反义DNMT1基因片段的SMMC 772 1细胞 ,其bax和bad表达 ,尤其是bax的表达 ,明显高于转入正义DNMT1基因片段和空载体的细胞 ,但对bcl 2的表达无影响。结论 转入反义DNMT1基因片段的肝癌SMMC 772 1细胞对TRAIL的敏感性明显增强 。

Objective To observe the sensitivity change of SMMC -7721 cells tra nsfected with antisense DNMT1 gene fragment to tumor necrosis factor relate d apoptosis inducing ligand (TRAIL) and its mechanism. Methods Cell survival rat e was measured by trypan blue, apoptosis rate by TUNEL method and the expression of bcl-2, bax and bad by flow cytometry. Results Cell survival rate of SMMC-77 21 cells transfected with antisense DNMT1 gene fragment was markedly lower than that transfected with sense DNMT1 gene fragment or empty vector (P<0.05 and 0.01 ), but the apoptosis rate was on the contrary (P<0.05 or 0.01). The expressi on o f bax and bad (especially the former), but not bcl-2 of SMMC-7721 cells trans fe cted with antisense DNMT1 gene fragment was markedly higher than those of SMMC- 7721 cells transfected with sense DNMT1 gene fragment or empty vector. Conclusion The sensitivity of SMMC-7721 cells to TRAIL can be enhanced by the transfectio n of antisense DNMT1 gene fragment, which may be related to the increase of bax and bad expression.