目的： 利用重组人5型复制缺陷型腺病毒载体介导miRNA-29a(miR-29a)过表达，观察miR-29a对人胃癌细胞系SGC-7901 及AGS的增殖抑制作用。 方法： 构建含pre-miR-29a的重组腺病毒Ad-miR29a及含LacZ基因的对照腺病毒Ad-LacZ，分别感染人胃癌SGC-7901及AGS细胞，采用real-time PCR法检测SGC-7901及AGS细胞中miR-29a的表达，CCK-8法检测miR-29a对SGC-7901及AGS细胞增殖的抑制作用，流式细胞术检测SGC-7901及AGS细胞的细胞周期，Transwell法检测miR-29a对SGC-7901及AGS细胞迁移能力的影响。 结果： 与Ad-LacZ对照组相比，Ad-miR29a组感染后胃癌SGC-7901及AGS细胞中miR-29a的表达均显著增加\[（17.35±0.71） vs （1.12±0.09），（26.50±1.09） vs （ 0.95±0.04）；均P<0.01\]；且胃癌SGC-7901及AGS细胞增殖明显受到抑制，感染6 d后D值均显著降低\[（0.54±0.03） vs （0.77±0.04），（0.70±0.03） vs （088±0.04）；均P<0.01）\]，而Ad-LacZ感染组与未感染组相比则无明显变化（P>0.05）；与Ad-LacZ对照组相比，Ad-miR29a组SGC-7901及AGS细胞中G0/G1期细胞比例均显著增加\[（63.10±4.91）% vs （47.60±5.31）%，（6980±3.15）% vs （54.60±4.22）%；均P<0.05\]，但胃癌SGC-7901及AGS细胞的迁移能力并没有明显差异。 结论： miR-29a过表达可有效抑制胃癌SGC-7901及AGS细胞的增殖，miR-29a有望成为治疗胃癌的新靶标。

Objective:To explore the inhibitory effect of miRNA-29a(miR-29a) on the proliferation of human gastric cancer cell lines SGC-7901 and AGS through over-expression of miR-29a mediated by the recombinant replication-deficient human adenovirus type 5 vector. Methods: The recombinant adenovirus Ad-miR-29a containing pre-miR-29a or control adenovirus Ad-LacZ containing LacZ gene was constructed and infected into human gastric cancer SGC-7901 and AGS cells, respectively. The expressions of miR-29a in SGC-7901 and AGS cells were detected by real-time PCR. CCK-8 assay was employed to examine the inhibitory effect of miR-29a on the proliferation of human gastric cancer cell lines. The flow cytometry assay was used to analyze cell cycle of SGC-7901 and AGS cells. The migration ablilities of SGC-7901 and AGS cells were assessed by Transwell assay. Results: Compared with the Ad-LacZ group, the Ad-miR29a group expressed higher level of miR-29a in both SGC-7901 and AGS cells (\[17.35±0.71\] vs \[1.12±0.09\], \[26.50±109\] vs \[0.95±0.04\], P<001). The proliferation of SGC-7901 and AGS was significantly inhibited in the Ad-miR29a group as compared with that in the Ad-LacZ group. Six days after Ad-miR29a infection, the D value was significantly decreased (\[0.54± 003\] vs \[0.77 ± 0.04\], \[0.70 ± 0.03\] vs \[0.88 ± 0.04\], P<0.01). The proliferation of cells in the Ad-LacZ group showed no significant changes as compared with that in the uninfected group (P>005). Meanwhile, The percentage of SGC-7901 or AGS cells arrested in G0/G1 period in the Ad-miR29a group was significantly higher than that in the Ad-LacZ group (\[63.10±4.91\]% vs \[47.60±5.31\]%，\[69.80±3.15\]% vs \[5460±422\]%, P<0.05\]. However, no significant changes were found in the migration ability of gastric cancer SGC-7901 and AGS cells. Conclusion:miR-29a can effectively suppress the proliferation of human gastric cancer cells, which makes a promising new therapeutic target for gastric cancer.

重庆市自然科学基金资助项目（No. CSTC, 2010BB5158，No. CSTC, 2011AC5024，No. CSTC, 2011jjA0878，No. CSTC, 2011jjA0882）