title: Evaluation of changes in the activity of proteolytic enzymes and their inhibitors in the processes that accompany the growth of gastric cancer.
abstract: BACKGROUND
  Many investigators have observed a correlation between the aggressiveness of malignant tumor growth and the levels of cysteine peptidases and their autogenous inhibitors. Cathepsins B and L are activated by pepsin in an acidic pH. This fact encouraged us to measure the activity of these enzymes in tissue samples of gastric cancer.
  
  
  METHODS
  We measured the activities of cathepsins B and L, and their precursors and inhibitors, in homogenates of tissue samples obtained from operations for gastric cancer. We compared the results for the homogenates of tissues from three different sites: the tumor center, the zone of cancer invasion (border of the tumor), and healthy tissue.
  
  
  RESULTS
  The highest activities of free cysteine peptidases and those in complexes with their inhibitors, as well as their precursors, were observed in the border of the tumor, while the activities in healthy tissue were significantly lower.
  
  
  CONCLUSIONS
  The local activities of cysteine peptidases and their inhibitors reflect the topographical differences between the center of the tumor, the zone of invasion, and healthy tissues in gastric cancer patients. In addition, the results for the pattern of changes in the activity of cysteine peptidases according to the degree of tissue infiltration were not dependent on the method of measurement (colorimetry vs spectrofluorometry).
authors.affiliation: Second Department of General and Oncological Surgery, Wroclaw Medical University, Wroclaw, Poland.
authors.forename: Wojciech
authors.initials: W
authors.lastname: Kielan
authors.forename: Janusz
authors.initials: J
authors.lastname: Suzanowicz
authors.forename: Maciej
authors.initials: M
authors.lastname: SiewiNski
authors.forename: Yousif
authors.initials: Y
authors.lastname: Saleh
authors.forename: Anna
authors.initials: A
authors.lastname: Janocha
authors.forename: Adam
authors.initials: A
authors.lastname: Skalski
authors.forename: Robert
authors.initials: R
authors.lastname: Tarnawa
mesh_terms: D000328:Adult; D000368:Aged; D002401:Cathepsin B / Q000032:analysis / Q000494:pharmacology*; D056668:Cathepsin L; D002403:Cathepsins / Q000032:analysis / Q000494:pharmacology*; D003546:Cysteine Endopeptidases; D018450:Disease Progression; D004791:Enzyme Inhibitors / Q000032:analysis; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D013274:Stomach Neoplasms / Q000201:enzymology* / Q000503:physiopathology* / Q000601:surgery
chemical_list: D004791:Enzyme Inhibitors; D002403:Cathepsins; D003546:Cysteine Endopeptidases; D002401:Cathepsin B; C534281:CTSL protein, human; D056668:Cathepsin L