lncRNA MEG3通过调控miR-21表达增加肺癌细胞放射敏感性

lncRNA MEG3 increases the radiosensitivity of lung cancer cells by regulating miR-21

目的探讨长链非编码RNA(lncRNA)MEG3对肺癌细胞H1299的放射敏感性调控机制。方法运用qRT-PCR法检测具有放射抗性的H1299细胞中MEG3、miR-21-5p的表达。将过表达对照组(转染pcDNA3.1)、过表达MEG3组(转染pcDNA3.1-MEG3)、抑制miR-NC组(转染anti-miR-NC)、抑制miR-21-5p组(转染anti-miR-21-5p)、过表达MEG3+过表达miR-NC组(转染pcDNA3.1-MEG3和miR-NC)、过表达MEG3+过表达miR-21-5p组(转染pcDNA3.1-MEG3和miR-21-5p mimics)均用脂质体法转染。克隆形成实验检测细胞存活分数,流式细胞术检测细胞凋亡,双荧光素酶报告基因检测实验检测细胞中MEG3与miR-21-5p的结合力。结果与正常肺上皮细胞相比,H1299细胞中MEG3表达明显降低,miR-21-5p表达明显升高;过表达MEG3或抑制miR-21-5p均可促进H1299细胞凋亡,增强放射敏感性;MEG3可靶向调控miR-21-5p的表达。过表达miR-21-5p可逆转MEG3对H1299细胞放射增强作用。结论lncRNA MEG3可增强H1299细胞放射敏感性,其机制也许可能与靶向miR-21-5p有关。

Objective To investigate the regulatory mechanism of long-chain non-coding RNA(lncRNA)MEG3 on the sensitivity of lung cancer cell line H1299 to irradiation.Methods The expression of MEG3 and miR-21-5p in lung cancer cell line H1299 was detected by qRT-PCR.Overexpression control group(transfected with pcDNA3.1),MEG3 overexpression group(transfected with pcDNA3.1-MEG3),miR-NC inhibition group(transfected anti-miR-NC),miR-21-5p inhibition group(transfected with anti-miR-21-5p),MEG3 overexpression+miR-NC overexpression group(co-transfected with pcDNA3.1-MEG3 and miR-NC),MEG3 overexpression+miR-21-5p overexpression group(co-transfected with pcDNA3.1-MEG3 and miR-21-5p mimics)were all transfected into H1299 cells by liposome method treated with 4Gy irradiation.Cell survival fraction was detected by colony formation assay.Cell apoptosis was detected by flow cytometry.The binding of MEG3 to miR-21-5p in cells was assessed by dual luciferase reporter assay.Results Compared with normal lung epithelial cells,the expression of MEG3 was significantly decreased,whereas the expression of miR-21-5p was significantly increased in the radioresistant lung cancer cells H1299.Overexpression of MEG3 or inhibition of miR-21-5p could promote the apoptosis and enhance the radiosensitivity of H1299 cells.MEG3 could targetedly regulate the expression of miR-21-5p.Overexpression of miR-21-5p could reverse the enhanced radiosensitivity of MEG3 to H1299 cells.Conclusion LncRNA MEG3 can enhance the sensitivity of lung cancer cells H1299 to irradiation.The mechanism may be related to targeting miR-21-5p.