title: Expression of matrix metalloproteinases and their inhibitors in squamous cell carcinoma of the tonsil and their clinical significance.
abstract: OBJECTIVE
  To investigate expressions of matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) in squamous cell carcinoma of the tonsil and to correlate expression profiles with clinicopathological characteristics.
  
  
  METHODS
  Paraffin blocks were obtained from 45 tonsil squamous cell carcinoma (SCC) patients, who underwent surgery as an initial treatment between 1994 and 2004, and from 20 normal controls. Expressions of MMP-2, MMP-9, MMP-13, TIMP-1, and TIMP-2 were investigated immunohistochemically.
  
  
  RESULTS
  The expressions of MMPs (except MMP-2) and TIMPs were found to be significantly different in tonsil SCC and normal control tissues. Furthermore, MMP-13 expression was found to be correlated with tumor invasion (P=0.05), and the expressions of MMP-9 and TIMP-1 with nodal metastasis (P=0.048, 0.031). No relation was found between MMP or TIMP expression and recurrence. However, MMP-9 expression was found to be significantly associated with 5-year survival in tonsil SCC patients by multivariate analysis (hazard ratio, 3.853; P=0.013).
  
  
  CONCLUSIONS
  Significant overexpressions of multiple MMPs and TIMPs were found in tonsil SCC tissues. Furthermore, our findings suggest that MMP-9 expression might be a useful prognostic factor.
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, Chung-Ang University College of Medicine, Seoul, Korea.
authors.forename: Sei Young
authors.initials: SY
authors.lastname: Lee
authors.forename: Sung Yoon
authors.initials: SY
authors.lastname: Park
authors.forename: Se-Heon
authors.initials: SH
authors.lastname: Kim
authors.forename: Eun Chang
authors.initials: EC
authors.lastname: Choi