title: Cysteine peptidase and its inhibitor activity levels and vitamin E concentration in normal human serum and colorectal carcinomas.
abstract: OBJECTIVE
  Cysteine peptidase (CP) and its inhibitor (CPI) are a matrix protease that may be associated with colorectal carcinoma invasion and progression, and vitamin E is also a stimulator of the immunological system. Our purpose was to determine the correlation between the expression of cysteine peptidases and their endogenous inhibitors, and the level of vitamin E in sera of patients with colorectal cancer in comparison with healthy individuals.
  
  
  METHODS
  The levels of cysteine peptidases and their inhibitors were determined in the sera of patients with primary and metastatic colorectal carcinoma and healthy individuals using fluorogenic substrate, and the level of vitamin E was determined by HPLC.
  
  
  RESULTS
  The levels of cysteine peptidases and their inhibitors were significantly higher in the metastatic colorectal cancer patients than that in the healthy controls (P<0.05). The activity of CP increased 2.2-fold, CPI 2.8-fold and vitamin E decreased 3.4-fold in sera of patients with metastasis in comparison with controls. The level of vitamin E in healthy individuals was higher, whereas the activity of cysteine peptidases and their inhibitors associated with complexes was lower than that in patients with cancer of the digestive tract.
  
  
  CONCLUSIONS
  These results suggest that the serum levels of CP and their inhibitors could be an indicator of the prognosis for patients with metastatic colorectal cancer. Vitamin E can be administered prophylactically to prevent digestive tract neoplasmas.
authors.affiliation: Clinic of Surgery and Oncology, Wroclaw Medical University, Poland.
authors.forename: Robert
authors.initials: R
authors.lastname: Szwed
authors.forename: Zygmunt
authors.initials: Z
authors.lastname: Grzebieniak
authors.forename: Yousif
authors.initials: Y
authors.lastname: Saleh
authors.forename: Godwin Bwire
authors.initials: GB
authors.lastname: Ekonjo
authors.forename: Maciej
authors.initials: M
authors.lastname: Siewinski
mesh_terms: D000328:Adult; D000368:Aged; D015415:Biomarkers; D015179:Colorectal Neoplasms / Q000175:diagnosis / Q000378:metabolism* / Q000556:secondary; D003546:Cysteine Endopeptidases / Q000097:blood*; D015853:Cysteine Proteinase Inhibitors / Q000097:blood*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D014810:Vitamin E / Q000097:blood*
chemical_list: D015415:Biomarkers; D015853:Cysteine Proteinase Inhibitors; D014810:Vitamin E; D003546:Cysteine Endopeptidases