title: Microarray analysis of gene expression alteration in human middle ear epithelial cells induced by micro particle.
abstract: OBJECTIVE
  The primary aim of this study is to reveal the effect of particulate matter (PM) on the human middle ear epithelial cell (HMEEC).
  
  
  METHODS
  The HMEEC was treated with PM (300 μg/ml) for 24 h. Total RNA was extracted and used for microarray analysis. Molecular pathways among differentially expressed genes were further analyzed by using Pathway Studio 9.0 software. For selected genes, the changes in gene expression were confirmed by real-time PCR.
  
  
  RESULTS
  A total of 611 genes were regulated by PM. Among them, 366 genes were up-regulated, whereas 245 genes were down-regulated. Up-regulated genes were mainly involved in cellular processes, including reactive oxygen species generation, cell proliferation, apoptosis, cell differentiation, inflammatory response and immune response. Down-regulated genes affected several cellular processes, including cell differentiation, cell cycle, proliferation, apoptosis and cell migration. A total of 21 genes were discovered as crucial components in potential signaling networks containing 2-fold up regulated genes. Four genes, VEGFA, IL1B, CSF2 and HMOX1 were revealed as key mediator genes among the up-regulated genes. A total of 25 genes were revealed as key modulators in the signaling pathway associated with 2-fold down regulated genes. Four genes, including IGF1R, TIMP1, IL6 and FN1, were identified as the main modulator genes.
  
  
  CONCLUSIONS
  We identified the differentially expressed genes in PM-treated HMEEC, whose expression profile may provide a useful clue for the understanding of environmental pathophysiology of otitis media. Our work indicates that air pollution, like PM, plays an important role in the pathogenesis of otitis media.
authors.affiliation: Department of Otorhinolaryngology-Head and Neck Surgery, Dongguk University Ilsan Hospital, Goyang, Gyeonggi, Republic of Korea.
authors.forename: Jae-Jun
authors.initials: JJ
authors.lastname: Song
authors.forename: Jee Young
authors.initials: JY
authors.lastname: Kwon
authors.forename: Moo Kyun
authors.initials: MK
authors.lastname: Park
authors.forename: Young Rok
authors.initials: YR
authors.lastname: Seo
mesh_terms: D000393:Air Pollutants / Q000009:adverse effects; D002454:Cell Differentiation / Q000235:genetics; D002478:Cells, Cultured; D015536:Down-Regulation; D004432:Ear, Middle / Q000166:cytology; D004847:Epithelial Cells / Q000166:cytology / Q000187:drug effects; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D006801:Humans; D035683:MicroRNAs / Q000235:genetics*; D046228:Microarray Analysis; D010033:Otitis Media / Q000235:genetics* / Q000473:pathology* / Q000503:physiopathology; D052638:Particulate Matter / Q000009:adverse effects*; D060888:Real-Time Polymerase Chain Reaction / Q000379:methods; D056910:Republic of Korea; D012680:Sensitivity and Specificity; D015398:Signal Transduction / Q000235:genetics; D015854:Up-Regulation
chemical_list: D000393:Air Pollutants; D035683:MicroRNAs; D052638:Particulate Matter
keywords: Air pollution; Microarray; Otitis media; Particulate matter; RNA