中文摘要：

目的：探讨siRNA抑制Mcl-1基因表达后对胃癌细胞MGC-803生物学行为的影响。方法合成针对Mcl-1的靶向siRNA（Mcl-1 siRNA组），以空白细胞（空白对照组）和分别转染脂质体试剂（脂质体对照组）及阴性对照siRNA（阴性对照组）作为对照组。噻唑蓝（MTT）实验检测Mcl-1 siRNA对MGC-803细胞增殖能力的影响；流式细胞术观察各组细胞凋亡及周期变化情况；转染48 h后应用Transwell小室分析细胞侵袭、迁移能力的变化。结果Mcl-1 siRNA组转染后24 h、48 h、72 h的A值低于3个对照组（P＜0.05），其细胞增殖抑制率分别为8.9%、21.6%和18.8%。转染48 h后，Mcl-1 siRNA组细胞凋亡率高于空白对照组、脂质体对照组和阴性对照组（%：19.61±1.66 vs 3.69±0.37 vs 3.54±0.47 vs 3.68±0.55，F=12.230，P＜0.05）。Mcl-1 siRNA组G0/G1[（41.03±1.86）%]、G2/M期[（1.80±0.46）%]比例均低于3个对照组，S期比例[（57.17±1.72）%]高于3个对照组（均P＜0.05）。Mcl-1 siRNA组侵袭、迁移实验中的穿膜细胞数（分别是42.00±4.00、76.33±3.51）均低于空白对照组（分别是79.33±3.51、108.00±3.61）、脂质体对照组（分别是74.67±2.52、110.67±4.04）和阴性对照组（分别是77.33±3.06、109.33±4.51）。以上指标在3个对照组间差异均无统计学意义。结论抑制Mcl-1表达可有效降低胃癌细胞的增殖、侵袭及迁移能力，并促进肿瘤细胞凋亡。

英文摘要：

Objective To investigate the effect of inhibiting Mcl-1 gene expression on the biological behavior of gas-tric cancer cell MGC-803 by using a small interference RNA （siRNA）. Methods Synthesized siRNA targeting Mcl-1（Mcl-1 siRNA group） was transfected into MGC-803 cells. On the other hand, MGC-803 cells transfected with negative siRNA （Mcl-1siRNA-NC group）, MGC-803 cells transfected with Lipofectamine 2000（liposomes control group）and vacant MGC-803 cells（blank control group）were used as controls. Proliferation of MGC-803 cells after transfection of Mcl-1 siRNA was investigated by MTT assay. After 48 h transfection of Mcl-1 siRNA, flow cytometry （FCM） was used to examine the apoptosis cells and cell cycle in all four groups. Polycarbonate membrane transwell chamber was used for evaluating the invasion and migration of the cell line. Results The absorbance of MGC-803 cells decreased greatly after transfected with Mcl-1siRNA for 24、48 and 72 h compared to those in control groups （P＆lt;0.05）;After transfected 48 h, apoptosis rate in Mcl-1siRNA group was higher than in the blank control group, liposomes control group and Mcl-1siRNA-NC group （%：19.61 ＆#177; 1.66 vs 3.69＆#177;0.37 vs 3.54＆#177;0.47 vs 3.68＆#177;0.55,F=12.230, P＆lt;0.05）,G0/G1 [（41.03＆#177;1.86）%] and G2/M phase ratio [（1.80＆#177; 0.46）%] in Mcl-1 siRNA group were lower than in the three control groups, S phase ratio [（57.17＆#177;1.72）%] in siRNA group was higher than in three control groups （P＆lt;0.05）. The number of transmembrane cells in Mcl-1 siRNA group in polycarbonate mem-brane transwell chamber experiment （42.00 ＆#177; 4.00,76.33 ＆#177; 3.51 respectively） were less than in blank control group （79.33 ＆#177; 3.51,108.00 ＆#177; 3.61 respectively）, liposome control group （74.67 ＆#177; 2.52,110.67 ＆#177; 4.04 respectively） and negative control group （77.33 ＆#177; 3.06,109.33 ＆#177; 4.51 respectively）. However, there was no significant difference in a