title: [Genome DNA hypomethylation in HaCaT cells after short exposure to SiO2 nanoparticles].
abstract: OBJECTIVE
  To observe the effect of SiO2 nanoparticles on genome DNA methylation profile in cultured cells.
  
  
  METHODS
  HaCaT cells were treated with nm-SiO2 at 2.5, 5 and 10 microg/ml and micro-SiO2 at 10 microg/ml for 24h and DAC treatment was given at 10 microg/ml group for 48h. The mC/(mC + C) percent was quantified by high performance capillary electrophoresis (HPCE) assay, and the expression level of mRNA and protein was detected by Real-time Q-PCR and westernblot assay. The activity of DNMTs was determined by DNA Methyltransferase Activity/Inhibition Assay Kit.
  
  
  RESULTS
  HPCE assay showed that nm-SiO2-treated cells were decreased in some degree. An average proportion of methylated mC/ (mC + C) was 4.82% in control, 2.7% in 2.5 microg/ml and 2.17% in 10 microg/ml groups, while 3.1% in micro-SiO2 groups, which got the consistent downtrend of genome methylation level during increasing nm-SiO2 dose nanoparticles. The mRNA expression level for DNMT1 decreased gradually with increased dose of nm-SiO2 nanoparticles. The alterations at protein level were similar to those at the mRNA level.
  
  
  CONCLUSIONS
  Genomic DNA methylation levels were decreased in HaCaT cells after short-term exposure to SiO2 nanoparticles.
authors: Shenzhen Center for Chronic Disease Control, Shenzhen 518020, China. spring417@126.com
authors: Chunmei
authors: C
authors: Gong
authors: Linqing
authors: L
authors: Yang
authors: Gonghua
authors: G
authors: Tao
authors: Qingcheng
authors: Q
authors: Liu
authors: Jianjun
authors: J
authors: Liu
authors: Zhixiong
authors: Z
authors: Zhuang
mesh_terms: D002460:Cell Line; D002478:Cells, Cultured; D019175:DNA Methylation / Q000187:drug effects*; D019075:Electrophoresis, Capillary; D016678:Genome / Q000235:genetics; D006801:Humans; D015603:Keratinocytes / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D053758:Nanoparticles / Q000633:toxicity*; D012822:Silicon Dioxide / Q000633:toxicity*; D012867:Skin / Q000166:cytology
chemical_list: D012822:Silicon Dioxide