SIRT2沉默对胃癌SGC-7901细胞增殖、迁移和侵袭的影响

Influences of SIRT2 silence on proliferation, migration and invasion of gastric cancer SGC-7901 cells

目的探究沉默信息调节蛋白2(SIRT2)对人胃癌SGC-7901细胞增殖、迁移和侵袭的影响及机制。方法采用实时荧光定量PCR(q RT-PCR)检测SIRT2在胃癌SGC-7901细胞和正常胃上皮GES-1细胞中的表达。采用RNA干扰技术处理SGC-7901细胞,SIRT2沉默组转染靶向SIRT2的干扰小RNA(SIRT2-siRNA1组、SIRT2-siRNA2组),阴性对照组转染SIRT2-si RNA阴性对照序列,空白对照组不转染。CKK-8法和平板细胞克隆形成实验检测SGC-7901细胞增殖, Transwell法检测SGC-7901细胞侵袭迁移能力,蛋白印迹检测SGC-7901细胞中SIRT2、丝氨酸/苏氨酸蛋白激酶(Akt)和磷脂酰肌醇-3激酶(PI3K)蛋白表达。结果人胃癌细胞SNU-1、KATO III、SGC-7901中SIRT2m RNA和蛋白水平均高于正常胃上皮GES-1细胞(P<0.05)。转染SIRT2-si RNA的SGC-7901细胞中SIRT2m RNA和蛋白水平均低于阴性及空白对照组(P<0.05);转染SIRT2-si RNA后,SGC-7901细胞增殖能力、克隆形成能力、迁移和侵袭能力均降低(P<0.05);转染SIRT2-siRNA后SGC-7901细胞中Akt、PI3K蛋白磷酸化程度显著下降(P <0.05)。结论 SIRT2在胃癌细胞中表达上调,沉默SIRT2可能通过调节PI3K/Akt通路抑制胃癌细胞增殖、迁移和侵袭,推测SIRT2可能作为潜在靶标应用于胃癌的基因治疗。

Objective To investigate the influences and mechanisms of silencing sirtuin-2（SIRT2） on proliferation, migration and invasion of human gastric cancer SGC-7901 cells. Methods The expressions of SIRT2 in gastric cancer SGC-7901 cells and normal gastric epithelial GES-1 cells was detected by real-time fluorescence quantitative PCR （qRT-PCR）. The SGC-7901 cells were treated with RNA interference technique, the SIRT2 silence group was transfected with interfering small RNAs targeting SIRT2 （group SIRT2-siRNA1, group SIRT2-siRNA2）, the negative control group was transfected with SIRT2-siRNA negative control sequence, blank control group was not transfected. CKK-8 assays and panel cell colony formation experiments were used to detect the proliferation of SGC-7901 cells. Transwell assay was applied to detect the invasion and migration abilities of SGC-7901 cells. The expressions of SIRT2, serine/threonine rotein kinase （Akt） and phosphatidylinositol-3 kinase （PI3K） in SGC-7901 cells were detected by Western blot. Results SIRT2 mRNA and protein levels in human gastric cancer cells SNU-1, KATO III and SGC-7901 were higher than those in normal gastric epithelial GES-1 cells （P 〈 0.05）. The levels of SIRT2 mRNA and protein in SGC-7901 cells transfected with SIRT2-siRNA were lower than those in negative and blank control groups （P 〈 0.05）; after SIRT2-siRNA transfection, the proliferation, clonality, migration and invasion of SGC-7901 cells were decreased （P 〈 0.05）; after transfection of SIRT2-siRNA, the phosphorylation of Akt and PI3K proteins in SGC-7901 cells were decreased significantly （P 〈 0.05）. Conclusion SIRT2 is up-regulated in gastric cancer cells and SIRT2 silence may inhibit proliferation, migration and invasion of gastric cancer cells by regulating PI3K/Akt pathway, on which it is speculated that SIRT2 may be used as a potential target for gene therapy of gastric cancer.