title: Activity of cysteine proteases and their inhibitors in the lymph nodes of larynx cancer patients.
abstract: BACKGROUND
  Cysteine endopeptidases and their inhibitors play an important role in the process of carcinogenesis. Positive correlation has been found between tumor invasiveness, its metastatic potential and the secretion of cysteine endopeptidases. Cysteine protease inhibitory activity is also altered in malignant tumors and various body fluids of patients with cancer.
  
  
  METHODS
  Total cysteine endopeptidase activity and cysteine proteinase inhibitory activity were measured in homogenates of cervical lymph node tissue surgically obtained from the larynx of cancer patients. The tissue samples were histologically examined, and each was divided into two parts: positive (PCN), with mostly cancer cells, and negative (NCN), with no cancer cells.
  
  
  RESULTS
  In the PCNs, the levels of the assayed enzymes and their inhibitors were significantly higher than in the NCNs. The mean values of cysteine protease activity were 2.70I2.29 and 1.59I1.28 for PCNs and NCNs, respectively (p<0.005). The mean values of cysteine protease inhibitors were 9.1I8.6 and 6.1I6.3 for PCNs and NCNs, respectively (p<0.02). An altered protease-inhibitor activity ratio was also found in PCN samples compared to NCNs.
  
  
  CONCLUSIONS
  These data suggest increased activity of cysteine peptidases and their inhibitors in the case of secondary tumor tissue. The cancer cells metastasized to lymph node tissue produce some alteration in balance between cysteine protease activity and the endogenous inhibitors of the proteases.
authors.affiliation: Department of Medical Biochemistry, Medical University of Wrocław, Poland.
authors.forename: Maciej
authors.initials: M
authors.lastname: Siewiński
authors.forename: Izabela
authors.initials: I
authors.lastname: Berdowska
authors.forename: Wojciech
authors.initials: W
authors.lastname: Mikulewicz
authors.forename: Jan
authors.initials: J
authors.lastname: Wnukiewicz
authors.forename: Jan
authors.initials: J
authors.lastname: Gutowicz
mesh_terms: D003546:Cysteine Endopeptidases / Q000378:metabolism*; D015853:Cysteine Proteinase Inhibitors / Q000378:metabolism*; D006801:Humans; D007822:Laryngeal Neoplasms / Q000209:etiology / Q000378:metabolism*; D008198:Lymph Nodes / Q000378:metabolism*; D008207:Lymphatic Metastasis
chemical_list: D015853:Cysteine Proteinase Inhibitors; D003546:Cysteine Endopeptidases