中文摘要：

目的研究纳米二氧化硅（nm-SiO2）对人皮肤表皮细胞（HaCaT）中p53基因的表达及基因启动子区甲基化的影响。方法分别以2.5、5、10μg/ml的nm-SiO2溶液和10μg/ml的微米级SiO2（micro-SiO2）处理HaCaT24h;以3μmol/LDNA甲基化转移酶抑制剂5-脱氧杂氮胞苷（DAC）处理48h的10μg/mlnm-SiO2组为阳性对照,并设立溶剂对照组。应用荧光定量PCR检测p53基因mRNA水平的表达,Western-blot法检测其蛋白水平的变化,应用甲基化特异性PCR（MSP）检测p53基因启动子区CpG岛的甲基化状态。结果nm-SiO2作用24h后,HaCaT细胞中p53基因表达呈上调趋势并且p53启动子区未检测出甲基化状态。结论nm-SiO2暴露可以上调HaCaT细胞中p53基因的表达,尚未发现这种上调与p53基因启动子区CpG岛的甲基化水平改变有关。

英文摘要：

Objective To study the effect of silicon dioxide nanoparticles on the expression and promoter region Cp G islands methylation of p53 gene in human Ha Ca T cell. Methods HaCaT cells were treated with nm-SiO2 at 0,2. 5,5 and 10 μg / ml and microSiO2 at 10 μg / ml for 24 h and DAC treatment was given at 10 μg / ml group for 48 h. Real time-PCR and western-blot assay was used to detect the expression of p53 mRNA and protein. The methylation specific polymerase chain reaction（ MSP） was used to detect the promoter region Cp G islands methylation status of p53 gene. Results After exposure to nano-SiO2 particles,the mRNA and protein expression of p53 was upregulated and the p53 promoter region Cp G islands showed demethylation. Conclusion nano-SiO2 can upregulate p53 expression in Ha Ca T cell and this increase has not been found to be related with the methylation of p53 gene promoter Cp G island level related.