工频磁场对人乳腺癌细胞基因表达的影响

Effects of 50 Hz magnetic fields on gene expression in MCF-7 cells

目的:了解工频磁场对人乳腺癌细胞株MCF-7细胞基因表达谱的影响,筛选工频磁场的可能反应基因,判断工频磁场对细胞功能的影响。方法:将体外传代培养的MCF-7细胞随机分为2组,分别接受0.4 mT的50 Hz磁场连续辐照和假辐照24 h。辐照结束后,立即提取细胞总RNA,用Affymetrix公司的人类基因组芯片U133A进行基因组转录水平分析,芯片实验数据采用MAS5.0软件和DMT 3.0软件进行分析。采用定量逆转录-聚合酶链反应(RT-PCR)验证基因芯片分析筛选到的候选差异表达基因。结果:MCF-7细胞受50 Hz磁场辐照后,有30个100%一致变化的候选差异基因。6次重复定量RT-PCR实验结果表明,MCF-7细胞受50 Hz磁场辐照后,SCNN1A基因和METTL3基因被显著性上调(P<0.05),GPR137B基因被显著性下调(P<0.05);而其它基因则未发生显著性改变(P>0.05)。结论:本研究检测到50 Hz工频磁场对MCF-7细胞基因表达的微弱变化,并确定了MCF-7细胞3个50 Hz工频磁场反应基因SCNN1A、GPR137B和METTL3。

Objective： To investigate whether 50 Hz magnetic fields （MF） can change the gene expression profile in MCF-7 cells and to screen MF responsive genes. Methods： In vitro cultured MCF-7 cells were continuously exposed or sham-exposed to 0. 4 mT of 50 Hz MF for 24 hours. Affymetrix Human Genome Genechips （U133A） were applied to analyze gene expression profiles in MF exposed and sham-exposed MCF-7 cells and the data were processed with Genechip data analysis software MAS 5.0 and DMT 3.0. Real-time RT-PCR assay was employed to examine the differentially expressed genes. Results： Thirty differentially expressed genes were screened with 100% consistency change calls in the MF exposed MCF-7 cells. Six independent real-time RT- PCR analyses showed that SCNN1A, METTL3 and GPR137B were slightly but statistically significantly changed in MCF-7 cells after exposure to 50 Hz MF （P〈0.05） ,while other analyzed genes exhibited slight up- and down-fluctuations in expressions and no increase or decrease in each gene expression reached statistical significance （P〉0.05）. Conclusion： The present study identified three 50 Hz MF responsive genes in MCF-7 cells and the biological consequences of expression changes in these MF responsive genes need to be further investigated.