title: [Hexosoaminidase gene expression in cholesteatoma in adults].
abstract: BACKGROUND
  Middle ear cholesteatoma is a cyst like structure composed of keratinizing squamous epithelium that contains keratin debris and subepithelial connective tissue. Bone resorption may lead to destruction of ossicular chain and temporal bone. The higher activity of N-acetyl-beta3-glucosaminidase (HEX) was noted in cholesteatoma tissue, compared to the controls. It is supposed, that HEX takes part in bone resorption in middle ear cholesteatoma. Using of HEX inhibitors in cultured fibroblasts and evaluation HEX mRNA expression may contribute to showing new ways of understanding cholesteatoma pathogenesis.
  
  
  OBJECTIVE
  was to elaborate cholesteatoma fibroblast cell culture (CF) technique and evaluate in vitro inhibition potential of pyrimethamine.
  
  
  METHODS
  Cholesteatoma and normal retroauricular skin sample obtained during surgical treatment were used in the study. CF served as a study group and fibroblast derived from skin specimens--as controls. Pyrimethamine was used at the concentrations of 1.5, 3, 10 and 20 microg/ml. The reverse transcriptase-polymerase chain reaction (RT-PCR) was carried out for the determination of HEX gene expression.
  
  
  RESULTS
  RT-PCR established the elevated expression of HEXA and HEXB mRNA in cholesteatoma. HEXA mRNA in CF was six times higher than in the controls. HEX mRNA expression found to be regulated by pyrimethamine. Inhibition of HEXA and HEXB mRNA expression was achieved when the highest concentration of PYR was used. Low concentrations of pyrimethamine upregulated HEX gene in CF.
  
  
  CONCLUSIONS
  Pyrimethamine, depending on its concentration, contributes to regulating the HEX gene expression in CF and controls. Pyrimethamine may be regarded as a new future research direction on factors, that may limit development of cholesteatoma.
authors.affiliation: Klinika Otolaryngologii Uniwersytetu Medycznego w Białymstoku.
authors.forename: Justyna
authors.initials: J
authors.lastname: Rutkowska
authors.forename: Ewa
authors.initials: E
authors.lastname: Olszewska
authors.forename: Edyta
authors.initials: E
authors.lastname: Waniewska
authors.forename: Sylwia
authors.initials: S
authors.lastname: Czechowska
authors.forename: Oksana
authors.initials: O
authors.lastname: Kowalczuk
authors.forename: Maria
authors.initials: M
authors.lastname: Borawska
authors.forename: Marlena
authors.initials: M
authors.lastname: Zukowska
authors.forename: Renata
authors.initials: R
authors.lastname: Markiewicz
authors.forename: Marek
authors.initials: M
authors.lastname: Rogowski
mesh_terms: D000328:Adult; D002478:Cells, Cultured; D018424:Cholesteatoma, Middle Ear / Q000378:metabolism*; D004424:Ear Canal / Q000201:enzymology; D015870:Gene Expression; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D012333:RNA, Messenger / Q000378:metabolism*; D012016:Reference Values; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012680:Sensitivity and Specificity; D001619:beta-N-Acetylhexosaminidases / Q000235:genetics / Q000378:metabolism*
chemical_list: D012333:RNA, Messenger; D001619:beta-N-Acetylhexosaminidases