title: Protection of prostatic acid phosphatase activity in human serum samples by plasmin inhibitors.
abstract: BACKGROUND
  The level of prostatic acid phosphatase in serum is an established marker for prostate carcinoma.
  
  
  METHODS
  Inactivation of homogeneous prostatic acid phosphatase from human seminal fluid by purified plasmin and human serum was studied in the presence and absence of bovine pancreatic trypsin inhibitor, a plasmin inhibitor, or phenylmethylsulfonylfluoride, a serine protease inhibitor.
  
  
  RESULTS
  Plasmin or serine protease inhibitors protect against prostatic acid phosphatase inactivation in serum samples.
  
  
  CONCLUSIONS
  The immediate addition of serine protease inhibitors to serum samples taken for prostatic acid phosphatase determinations should provide more accurate results and permit extended storage of samples. The stabilization of the enzyme activity and immunological properties of prostatic acid phosphatase in blood samples by these protease inhibitors resurrects the clinical significance of prostatic acid phosphatase measurements in prostate cancer screenings.
authors: Edward A. Doisy Department of Biochemistry and Molecular Biology, Saint Louis University School of Medicine, 1402 S. Grand Boulevard, St. Louis, MO 63104, USA.
authors: Abdul
authors: A
authors: Waheed
authors: Robert L
authors: RL
authors: Van Etten
mesh_terms: D000135:Acid Phosphatase; D000933:Antifibrinolytic Agents / Q000494:pharmacology*; D015415:Biomarkers / Q000097:blood; D004795:Enzyme Stability / Q000187:drug effects; D006801:Humans; D008297:Male; D008403:Mass Screening; D009928:Organ Specificity; D011467:Prostate / Q000201:enzymology; D011471:Prostatic Neoplasms / Q000097:blood / Q000175:diagnosis* / Q000201:enzymology; D011480:Protease Inhibitors / Q000494:pharmacology; D011489:Protein Denaturation / Q000187:drug effects; D017027:Protein Tyrosine Phosphatases / Q000037:antagonists & inhibitors / Q000097:blood* / Q000276:immunology / Q000378:metabolism*; D013048:Specimen Handling / Q000379:methods*; D013997:Time Factors
chemical_list: D000933:Antifibrinolytic Agents; D015415:Biomarkers; D011480:Protease Inhibitors; D000135:Acid Phosphatase; C428439:prostatic acid phosphatase; D017027:Protein Tyrosine Phosphatases