title: [Inhibition of micro RNA-9 expression promotes UV-induced ROS damage in nasopharyngeal carcinoma cells].
abstract: OBJECTIVE
  To investigate the effects of down-regulated miR-9 expression on ultraviolet rays (UV)-induced reactive oxygen species (ROS) damage in nasopharyngeal carcinoma (NPC) cells.
  
  
  METHODS
  The NPC cells were transfected with inhibitors of miR-9 by lipofectamine to decrease the expression of miR-9, and the cells transfected with inhibitor control as the control. ROS levels following UV exposure were examined with DCF-DA method and the concentration of glutathione was analyzed via the benzoic acid method; DNA damage and apoptosis also were evaluated.
  
  
  RESULTS
  There was significant difference in ROS levels between miR-9 expression-inhibited cells and control cells (26 895 ± 218 vs 15 765 ± 927, t = 39.754, P < 0.001), and also there were significant differences in DNA damage rates (28.0% ± 10.0% vs 23.6% ± 9.2%) and in apoptosis rates (8.0% ± 0.9% vs 4.5% ± 0.8%) following UV exposure between two groups of cells. The miR-9 expression-inhibited cells showed lower level (1.87 ± 0.15) µmol/L of glutathione compared with the control cells (9.85 ± 0.15) µmol/L (t = -48.832, P < 0.001).
  
  
  CONCLUSIONS
  Inhibition of miR-9 expression promoted UV-induced ROS damage in nasopharyngeal carcinoma cells.
authors.affiliation: Department of Otorhinolaryngology of Shenzhen People's Hospital, Shenzhen 518020, China.
authors.forename: Chao-pan
authors.initials: CP
authors.lastname: Zheng
authors.forename: Ling
authors.initials: L
authors.lastname: Han
authors.forename: Wei-jian
authors.initials: WJ
authors.lastname: Hou
authors.forename: Yi-hui
authors.initials: YH
authors.lastname: Wen
authors.forename: Ran
authors.initials: R
authors.lastname: Fu
authors.forename: Ren-qiang
authors.initials: RQ
authors.lastname: Ma
authors.forename: Wei-ping
authors.initials: WP
authors.lastname: Wen
mesh_terms: D017209:Apoptosis; D002277:Carcinoma; D045744:Cell Line, Tumor; D004249:DNA Damage; D006801:Humans; D035683:MicroRNAs / Q000378:metabolism*; D000077274:Nasopharyngeal Carcinoma; D009303:Nasopharyngeal Neoplasms / Q000378:metabolism*; D017382:Reactive Oxygen Species / Q000378:metabolism*; D014162:Transfection
chemical_list: D035683:MicroRNAs; D017382:Reactive Oxygen Species