title: Role of matrix metalloproteinase-9 in in vitro invasion of esophageal carcinoma cells.
abstract: OBJECTIVE
  Although some investigators recently suggested that MMP-9 may play a critical role in invasion and metastasis, along with MMP-2, in esophageal carcinoma, there has been no direct evidence that MMPs play a critical role in the actual invasion of esophageal carcinoma cells. Here, we investigated the role of MMPs in the in vitro invasion of esophageal carcinoma cell lines (TE-series).
  
  
  METHODS
  Our methods included in vitro invasion assay, gelatin zymography, and enzyme-linked immunosorbent assay (ELISA).
  
  
  RESULTS
  Four cell lines (but not TE-5) secreted MMP-2 and MMP-9 in the culture medium. Using a quantitative in vitro invasion assay, we found a significant (P = 0.002) correlation between the extent of in vitro invasion and the amount of MMP-9, but not of MMP-2, secreted into the conditioned medium in the four cell lines. In these cell lines, R-94138, a specific MMP-9 inhibitor, inhibited in vitro invasion in a dose-dependent manner. Although TE-5 did not secrete MMP-2 or MMP-9, the cells showed a strong in vitro invasion.
  
  
  CONCLUSIONS
  Our data suggest that most of the esophageal carcinoma cell lines use MMP-9 for in vitro invasion, but others may use proteinase(s) other than MMP-9.
mesh_terms: D002294:Carcinoma, Squamous Cell / Q000378:metabolism / Q000473:pathology*; D010450:Endopeptidases / Q000378:metabolism*; D004797:Enzyme-Linked Immunosorbent Assay; D004938:Esophageal Neoplasms / Q000378:metabolism / Q000473:pathology*; D006801:Humans; D020780:Matrix Metalloproteinase 9 / Q000378:metabolism*; D009361:Neoplasm Invasiveness; D014407:Tumor Cells, Cultured / Q000378:metabolism / Q000473:pathology
chemical_list: D010450:Endopeptidases; D020780:Matrix Metalloproteinase 9