Objective: To investigate the effects of overexpression of long noncoding RNA (lncRNA) MEG3 on the proliferation and invasion of glioblastoma U251 cells by suppressing the expression of hypoxia inducible factor 1α(HIF1α).
Methods: The expression of lncRNA MEG3 and HIF1α mRNA were examined in human fetal glial cells (HFGCs) and U251 cells using realtime quantitative PCR (qRT-PCR), and the expression of HIF1α protein was detected with Western blotting.U251 cells in normal culture or transfected with pcDNA3.1 vector (NC group) or pcDNA3.1-MEG3 vector via lipofectamine2000 were exposed to hypoxia for 12h, and the expressions of HIF1α mRNA and protein were detected with qRT-PCR and Western blotting, respectively.MTT assay and Transwell assay were employed to examine the influence of MEG3 overexpression on the proliferation and invasion of U251 cells.
Results: The expression of MEG3 was significantly lower and HIF1α mRNA and protein expressions were significantly higher in U251 cells than in HFGCs (P < 0.05).In U251 cells, overexpression of MEG3 significantly decreased the mRNA and protein expressions of HIF1α(P < 0.05).Hypoxic exposure for 12h also resulted in significantly lowered expression of HIF1α protein in U251 cells (P < 0.05).Overexpression of MEG3 obviously suppressed the proliferation and invasiveness of U251 cells (P < 0.05).
Conclusions: MEG3 overexpression inhibits the proliferation and invasion of U251 cells through suppressing the expression of HIF1α mRNA and protein, suggesting that MEG3 may serve as a potential therapeutic target for glioblastomas.
目的: 探讨lncRNA MEG3过表达通过调控HIF1α对胶质瘤U251细胞增殖和侵袭的影响。
方法: 采用荧光实时定量PCR (qRT-PCR)法检测人胚脑胶质细胞(HFGC)和胶质瘤U251细胞lncRNA MEG3和HIF1α的表达, HIF1α蛋白的表达则采用Western blot法检测; 将U251细胞分为3组, 6孔/组。Con组:正常培养的U251细胞; NC组:采用脂质体lipofectamine2000将pcDNA3.1空载体转染至U251细胞; pcDNA3.1-MEG3组:采用脂质体lipofectamine2000将pcDNA3.1-MEG3载体转染至U251细胞。另外, 对上述3组细胞进行缺氧处理12 h。分别通过qRT-PCR法或Western blot法检测各组细胞HIF1α的表达, 采用MTT法检测各组U251细胞增殖情况, Transwell侵袭实验检测各组U251细胞的侵袭。
结果: U251细胞中lncRNA MEG3的表达明显低于HFGC (P＜0.05), 而HIF1α mRNA和蛋白的表达均高于HFGC (P＜0.05);U251细胞中, MEG3过表达组HIF1α mRNA和蛋白的表达均降低(P＜0.05), 而且在缺氧12 h后HIF1α蛋白的表达亦降低(P＜0.05)。过表达MEG3导致细胞增殖及侵袭力下降(P＜0.05)。
结论: lncRNA MEG3通过调控HIF1α的表达抑制U251细胞的增殖和侵袭, 并可能为胶质瘤的临床治疗提供潜在的分子靶点。
Keywords: glioblastoma; hypoxia inducible factor 1 alpha; invasion; long noncoding RNA MEG3; proliferation.