LncRNA-MEG3对胃癌生物学特性及铂类化疗敏感性的研究

Effect of LncRNA-MEG3 on proliferation and apoptosis of gastric cancer and chemosensitivity of cisplatin

目的探讨Lnc RNA-MEG3对胃癌增殖、凋亡及顺铂化疗敏感性的影响。方法以人正常胃黏膜上皮细胞GES1作为对照细胞,实时荧光定量聚合酶链反应(qRT-PCR)检测胃癌MKN28、SGC7901、AGS及BGC823细胞中LncRNA-MEG3的表达;将过表达MEG3的质粒转染BGC823细胞作为pcDNA3.1-MEG3组,转染空白质粒的阴性对照作为pcDNA3.1组,同时设置Control组;将BGC823细胞分为pcDNA3.1组、pcDNA3.1-MEG3组、顺铂组及pcDNA3.1-MEG3+顺铂组。qRT-PCR检测转染48 h后细胞中LncRNA-MEG3的表达;pcDNA3.1-MEG3、顺铂单独或共同处理BGC823细胞,细胞计数试剂盒法及流式细胞仪分别检测细胞活力及凋亡率;Western blotting检测STAT3、磷酸化的信号转导与转录因子3(p-STAT3)、Cyclin D1和Bcl-2的表达。结果胃癌细胞中LncRNA-MEG3的表达均低于GES1细胞(P <0.05);4组LncRNA-MEG3相对表达量比较,差异有统计学意义(P <0.05);pcDNA3.1-MEG3组和顺铂组Cyclin D1、Bcl-2及p-STAT3的蛋白表达低于pcDNA3.1组(P <0.05),细胞凋亡率高于pcDNA3.1组(P <0.05)。结论胃癌细胞中LncRNA-MEG3表达降低,过表达LncRNA-MEG3可降低胃癌细胞活力并诱导细胞凋亡,增加顺铂的化疗敏感性,其机制与下调STAT3信号通路有关。

To investigate the effect of LncRNA-MEG3 on the proliferation and apoptosis of gastric cancer and the chemosensitivity of cisplatin. Methods Using human normal gastric epithelial cell GES1 as control cells, the expressions of LncRNA-MEG3 in MKN28, SGC7901, AGS and BGC823 gastric cancer cells were detected by qRT-PCR;the plasmid that overexpressed MEG3 was transfected into BGC823 cells (pcDNA3.1- MEG3 group), and blank plasmid was added as negative control (pcDNA3.1 group), and blank control group was set up, and the expression of LncRNA-MEG3 was detected by qRT-PCR cells transfected with 48h;BGC823 cells were treated by pcDNA3.1-MEG3 and cisplatin alone or together, and CCK8 assay and flow cytometry were used to detect cell viability and apoptosis rate;the expression of STAT3, p-STAT3Cyclin D1 and Bcl-2 protein were detected by western blotting. Results The expression of LncRNA-MEG3 in gastric cancer cells was lower than that in GES1 cells (P < 0.05);the relative expression of LncRNA-MEG3 in four groups was significantly different (P < 0.05);the expressions of Cyclin D1, Bcl-2 and p-STAT3 protein were significantly lower in pcDNA3.1-MEG3 group and cisplatin group than those in pcDNA3.1 group, but apoptosis rate was significantly higher (P < 0.05). Conclusions The expression of LncRNA-MEG3 decreases in gastric cancer cells. Overexpression of LncRNA-MEG3 can reduce gastric cancer cell viability and induce cell apoptosis, and increase the chemosensitivity of cisplatin, which is related to downregulation of STAT3 signaling pathway.