title: Cathepsin B expression in tumour cells and laminin distribution in pulmonary adenocarcinoma.
abstract: OBJECTIVE
  To determine the correlation between cathepsin B expression and laminin distribution in pulmonary adenocarcinoma tissue.
  
  
  METHODS
  The distribution of cathepsin B and laminin was examined in 28 formalin fixed, paraffin wax embedded specimens of pulmonary adenocarcinoma tissue, using a double immunostaining technique with commercially available antibodies to cathepsin B and laminin, respectively.
  
  
  RESULTS
  Tumour cells in 23 (82%) cases reacted to cathepsin B: 13 cases were weakly positive and 10 were strongly positive. Laminin in tumour associated basement membrane produced various staining patterns: two cases had an almost continuous distribution of laminin in tumour associated basement membrane in the tumour tissues, while a moderately discontinuous laminin distribution pattern was found in 12 cases, and a highly fragmented pattern was found in 14 cases. The degree of cathepsin B expression in tumour cells was significantly correlated with the break up of laminin staining. In some cases a discontinuous pattern of tumour associated laminin was frequently observed adjacent to cathepsin B positive tumour cell nests.
  
  
  CONCLUSIONS
  Considering that cathepsin B has the capacity to degrade basement membrane components, including laminin, the inverse correlation shown in this study between the increase in cathepsin B expression by tumour cells and the diminution of laminin in tumour associated basement membrane could reflect local progression and spread by pulmonary adenocarcinoma.
authors.affiliation: Department of Thoracic Surgery, Centre for Adult Diseases, Osaka, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Higashiyama
authors.forename: O
authors.initials: O
authors.lastname: Doi
authors.forename: K
authors.initials: K
authors.lastname: Kodama
authors.forename: H
authors.initials: H
authors.lastname: Yokouchi
authors.forename: R
authors.initials: R
authors.lastname: Tateishi
mesh_terms: D000230:Adenocarcinoma / Q000737:chemistry* / Q000201:enzymology; D001485:Basement Membrane / Q000737:chemistry; D002401:Cathepsin B / Q000032:analysis*; D006801:Humans; D007124:Immunoenzyme Techniques; D007797:Laminin / Q000032:analysis*; D008175:Lung Neoplasms / Q000737:chemistry* / Q000201:enzymology; D009363:Neoplasm Proteins / Q000032:analysis*
chemical_list: D007797:Laminin; D009363:Neoplasm Proteins; D002401:Cathepsin B