环氧化酶-2RNA干扰对肺癌A549细胞凋亡及caspase家族的影响

目的观察环氧化酶-2（COX-2）RNA干扰对肺癌细胞凋亡的影响，以及对凋亡调控蛋白caspase-8、caspase-9、caspase-3的调控作用。方法构建COX-2特异性干扰质粒，并转染至肺癌A549细胞株中，AnnexinV-FITC／PI联合流式细胞仪检测细胞凋亡，Western Blot检测caspase-8、caspase-9、caspase-3的活性。结果成功构建COX-2特异性干扰质粒并转染至肺癌A549细胞株中，获得抑制COX-2表达的肺癌细胞模型；干扰COX-2的A549细胞凋亡率（24．3±2．46）％]较未干扰组（6．52±0．13）％]明显升高（P〈0．01）。干扰COX-2的肺癌细胞．4549caspase．8蛋白表达（0．86±0．09）较未干扰组（0．12±0．01）明显升高（P〈0．01），caspase-3蛋白表达（0．94±0．09）较未干扰组（0．16±0．02）明显升高（P〈0．01），caspase-9蛋白表达（1．12±0．11）较未干扰组（0．13±0．01）明显升高（P〈0．01）。结论干扰COX-2可以促进肺癌A549细胞的凋亡，并且活化caspase-8及caspase-9，从而活化caspase-3。

Effects of cyclooxygenase-2 RNA interference to the apoptosis of gastric cancer cell A549 and the expression of caspase family

Objective To observe the effects of COX-2 RNA interference （RNAi） to apoptosis of A549 cells and the expression of caspase-8/9/3. Methods The COX-2 specific RNAi plasmid was constructed and transfected into A549 cells. The cell apoptosis was detected by Annexin V-FITC/PI combined with flow eytometry and the levels of caspase-8/9/3 were detected by Western Blot. Results The COX-2 specific RNAi plasmid was constructed and transfected into A549 cells, and then the cell model of interferenced COX-2 expression was obtained. The apoptosis rate in interferenced group（24. 3± 2.46% ）was significant higher than that in non-interfereneed group（6. 52 ± 0. 13% ） （ P 〈 0. 01 ）. Western-blot detection demonstrated that the expression of caspase-8 protein in interferenced group （0.86 ± 0. 09） was obvious higher than that in control group （ 0. 12 ± 0. 01 ） （ P 〈 0. 01 ）, the expression of caspase-3 protein in interferenced group （0.94 ± 0.09 ） was obvious higher than that in control group （ 0. 16 ± 0. 02 ） （ P 〈 0. 01 ） and the expression of caspase-9 protein in interferenced group （ 1.12 ± 0. 11 ） was obvious higher than that in control group（0. 13 ± 0. 01 ）（P 〈 0. 01 ）. Conclusions COX-2 RNAi enhanced apoptosis of A549 cells and strengthened the expression of caspase-8/9/3 in A549 cells.