摘要目的 探讨敲低信号转导及转录活化因子3(STAT3)表达对人胶质瘤细胞系U251细胞功能的影响及相关作用机制. 方法 脂质体介导STAT3反义寡聚核苷酸转染人胶质瘤细胞系U251细胞,同时设无义序列组和空白对照组,48 h后MTT检测STAT3反义核苷酸对U251细胞增殖的影响,流式细胞仪检测各组细胞周期、细胞凋亡的变化,Transwell实验检测各组细胞的侵袭能力,Western blotting检测STAT3和磷酸化STAT3(pSTAT3)蛋白、尿激酶型纤溶酶原激活物受体(uPAR)、B细胞淋巴瘤/白血病-2相关X蛋白(Bax)、B细胞淋巴瘤/白血病-2(Bcl-2)的表达水平. 结果 与空白对照组、无义序列组比较,STAT3反义核苷酸组细胞的相对存活率降低,G1/G0期细胞比例、细胞凋亡增加,Transwell实验显示滤膜细胞数明显减少,STAT3、pSTAT3、uPAR和Bcl-2蛋白的表达降低、Bax蛋白表达增加,差异均有统计学意义(P＜0.05). 结论 反义STAT3可能通过调节相关基因表达抑制U251细胞侵袭能力并诱导其调亡,STAT3可作为胶质瘤基因治疗的有效靶点.

abstractsObjective To investigate the role of signal transducer and activator of transcription 3 (STAT3) knockdown in regulating the invasion and apoptosis of glioma cells.Methods Liposome-mediated STAT3 antisense oligonucleotide was transfected into the U251 glioma cells;nonsense sequence group and blank control group were also established.The effect of STAT3 antisense oligonucleotide on the growth of U251 glioma cells was examined by MTT assay; the cell cycle and apoptosis were evaluated by flow cytometry; the cell migration was determined by Transwell invasion assay.Western blotting was employed to explore the protein expressions of STAT3 and pSTAT3,urokinase-type plasminogen activator receptor (uPAR),Bax and Bcl-2 in glioma cells.Results As compared with the nonsense sequence group and blank control group,liposome-mediated STAT3 antisense oligonucleotide group had lower survival rate,inhibited cell proliferation and cells being arrested at G0/G1 phases; Transwell invasion assay indicated that STAT3 antisense oligonucleotide suppressed the invasion and promoted the apoptosis of U251 cells.The STAT3,pSTAT3,uPAR and Bcl-2 expression levels in the iposome-mediated STAT3 antisense oligonucleotide group were signficantly decreased as compared with those in the nonsense sequence group and blank control group,while Bax level was obviously elevated (P＜0.05).Conclusion STAT3 antisense oligonucleotide can inhibit the invasion and promote the apoptosis of U251 cells by regulating its downstream gene expression; STAT3 can be used as an effective target for glioma gene therapy.