miR-645调控干扰素诱导蛋白2对肺癌细胞增殖和侵袭的作用及机制

Role of miR-645 in promoting proliferation and invasion of lung cancer cells by regulating IFIT2 and its mechanism

目的探讨miR-645对干扰素诱导蛋白2(interferon inducible protein 2, IFIT2)的表达以及对肺癌细胞增殖、侵袭的影响。方法采用反转录PCR法检测肺癌组织和细胞以及配对的正常组织和细胞中miR-645相对表达量。对数生长期人肺癌细胞H460分为对照组和转染组,分别转染NC mimic和miR-645 mimic,采用CCK-8法检测2组细胞增殖率,采用Transwell小室实验检测2组细胞侵袭率;采用荧光素酶报告基因实验检测2组细胞miR-645和IFIT2的结合活性;采用反转录PCR法检测2组细胞miR-645和IFIT2 mRNA相对表达量。结果肺癌组织(3.25±0.25)和肺癌细胞(2.85±0.22)miR-645相对表达量均高于正常肺组织(1.00±0.12)和正常肺上皮细胞(1.00±0.08)(P<0.05);转染组细胞增殖率[(220±12)%]、细胞侵袭率[(65.6±5.2)%]均高于对照组[(100±8)%、(25.9±3.2)%](P<0.05);转染组野生型3’UTR(WT-IFIT2)相对荧光素酶活性(0.48±0.06)低于对照组(1.00±0.12)(P<0.05),突变型3’UTR(MUT-IFIT2)相对荧光素酶活性(1.12±0.09)与对照组(1.00±0.08)比较差异无统计学意义(P>0.050);转染组细胞IFIT2 mRNA相对表达量(0.32±0.05)低于对照组(1.00±0.10)(P<0.05),miR-645在肺癌细胞中表达水平与IFIT2呈负相关(r=-0.743,P<0.001)。结论 miR-645可促进肺癌细胞H460的增殖和侵袭,其作用机制是通过调控IFIT2的表达而实现。

Objective To investigate the influences of miR-645 on the expression of interferon inducible protein 2(IFIT2) and the proliferation and invasion of lung cancer cells. Methods Reverse transcription PCR was used to detect the relative expression of miR-645 in lung cancer tissues and cells as well as their matched normal tissues and cells. Human lung cancer cell line H460 in logarithmic growth phase was divided into transfection group and control group, transfected with miR-645 mimic and NC mimic, respectively. CCK-8 assay was used to detect the cell proliferation rate. Transwell chamber assay was used to detect the invasion rate. Luciferase report experiment was used to verify the binding activity of miR-645 and IFIT2. Reverse transcription PCR was used to detect the relative expressions of miR-645 and IFIT2. Results The relative expressions of miR-645 in lung cancer tissues(3.25±0.25) and lung cancer cells(2.85±0.22) were higher than those in normal lung tissues(1.00±0.12) and normal lung epithelial cells(1.00±0.08)(P<0.05). The cell proliferation rate((220±12)%) and invasion rate((65.6±5.2)%) in transfection group were higher than those in control group((100±8)%,(25.9±3.2)%)(P<0.05). The relative luciferase activity of the wild type 3’UTR was lower in transfection group(0.48±0.06) than that in control group(1.00±0.12)(P<0.05), and the relative luciferase activity of the mutant 3’UTR showed no significant difference between transfection group(1.12±0.09) and control group(1.0±0.08)(P>0.05). The relative expression of IFIT2 mRNA was lower in transfection group(0.32±0.05) than that in control group(1.00±0.10)(P<0.05). The expression of miR-645 in lung cancer cells was negatively correlated with IFIT2(r=-0.743, P<0.001). Conclusion miR-645 can aggravate the proliferation and invasion of H460 by regulating the expression of IFIT2.