中文摘要：

目的观察丝氨酸/苏氨酸激酶15基因（serine/threonine kinase15,STK15）沉默后对胃癌细胞系MKN45体内外生长的抑制作用,探讨STK15基因作为胃癌靶点治疗的可行性.方法应用RNA干扰技术（RNA interference,RNAi）抑制STK15基因的表达;Western blot检测STK15蛋白质的表达变化;体外侵袭实验检测MKN45细胞侵袭能力的变化;MTT法检测MKN45细胞增殖速度的变化.将裸鼠随机分成2组,每组10只,皮下移植经STK15siRNA处理的MKN45细胞,观察其成瘤性的改变.结果MKN45细胞经STK15 siRNA作用后,蛋白表达水平均明显降低;STK15-组与对照组比较体外侵袭能力明显下降[平均A值为（182±27）比（308±38）,P＜0.05];更多的MKN45细胞聚集于G2/M期附近[G2期DNA含量细胞为（30±5）%比（14±3）%,P＜0.05];增殖速度明显减缓（P＜0.05）;在裸鼠体内成瘤性明显减低[平均肿瘤重量为（0.15±0.07）g比（0.29±0.16）g,P＜0.05].结论靶向STK15的siRNA可在体内外抑制胃癌MKN45细胞的增殖,STK15有可能成为胃癌治疗的靶点.

英文摘要：

Objective To observe the effect of STK15 gene silencing on the growth of gastric cancer cell line-MKN45 in vitro and vivo. Methods STK15 expression was inhibited by RNAi techenique, STK15 protein level was detected by Western blot, the ability of MKN45 invasion in vitro was assessed by cell migration and invasion assay, the change of cell cycle distribution was detected by flow-cytometry, MKN45 proliferation was measured by MTT method, and MKN45 cells treated with STK15 siRNA were transplanted subcutanuously in nude mice and their tumorgenesis ability were observed. Results After treatment with STK15 siRNA, STK15 protein level decreased obviously. Compared with control group, STK15^- group showed lower invasion ability in vitro [ mean A value ： （ 182 ± 27） vs. （308 ± 38 ）, P 〈 0. 05 ] , more MKN45 cells accumulated at G2/M phase [ mean G2 DNA content cells： （ 30 ± 5 ） % vs. （ 14 ± 3 ） % , P 〈 0. 05 ] and proliferated slowerly （ P 〈 0. 05 ）, the tumorgenesis ability in vivo also substantially decreased [ mean tumor weight： （ 0. 15 ± 0. 07 ） g vs. （ 0.29 ± 0. 16 ） g, P 〈 0. 05 ]. Conclusions siRNA targeting STK15 could inhibit the proliferation of MKN45 cells in vitro and vivo, STK15 could be a novel target for the treatment of gastric cancer.