title: [The expression of matrix metalloproteinase-9 and tumor necrosis factor-alpha in cholesteatoma].
abstract: OBJECTIVE
  To observe the expression of MMP-9, TNF-alpha in cholesteatoma and to determine their roles in the destruction of bone.
  
  
  METHODS
  Immunohistochemical method (SP) and the computer image quantitative analysis were used to examine the expression of TNF-alpha, MMP-9 in 22 samples from cholesteatoma and 20 normal cases. At the same time, the correlation between the expressions of the two indexes and the erosion of ossicles were observed.
  
  
  RESULTS
  MMP-9 protein was only expressed in cholesteatoma stromal cells. TNF-alpha was expressed in both epithlium and stromal cells. The results of the computer image quantitative analysis showed that the mean optical density of MMP-9 and TNF-alpha in cholesteatoma were higher than that in normal skin epithelial tissue (P < 0.05), in addition, the two indexes were relative to the extent of ossicle destruction.
  
  
  CONCLUSIONS
  MMP-9 and TNF-alpha are overexpressed in cholesteatoma and they are associated with ossicle destruction, which shows that MMP-9 and TNF-alpha are responsible for bone destruction in cholesteatoma; MMP-9 and TNF-alpha have a correlation in their expression, which suggest that the two factors act on each other possibly; Overexpression of MMP-9 is only observed in stromal cells and the immunostain of TNF-alpha also is observed in stromal cells which indicates that stromal cells play an important role in bone destruction.
authors.affiliation: Department of Otolaryngology, the First Affiliated Hospital of Zhengzhou University, Zhengzhou, 450052, China.
authors.forename: Nan
authors.initials: N
authors.lastname: Li
authors.forename: Zhaobing
authors.initials: Z
authors.lastname: Qin
authors.forename: Mingmin
authors.initials: M
authors.lastname: Dong
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D018424:Cholesteatoma, Middle Ear / Q000378:metabolism* / Q000473:pathology; D005260:Female; D006801:Humans; D008297:Male; D020780:Matrix Metalloproteinase 9 / Q000096:biosynthesis*; D008875:Middle Aged; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis*
chemical_list: D014409:Tumor Necrosis Factor-alpha; D020780:Matrix Metalloproteinase 9