title: The value of serum GPDA-F for the diagnosis of primary hepatocellular carcinoma.
abstract: OBJECTIVE
  To investigate the role of glycylproline dipeptidyl aminopeptidase isoenzymes in the diagnosis of primary hepatocellular carcinoma (PHC).
  
  
  METHODS
  We developed a stage gradient polyacrylamide gel electrophoresis system to separate serum GPDA isoenzymes. Total GPDA activities, alpha-fetoprotein, the sizes of tumors and alanine aminotransferase (ALT) activities were also measured simultaneously and the correlation between GPDA-F and these indices was analyzed.
  
  
  RESULTS
  Serum GPDA was separated into two bands, namely fast band (GPDA-F) and slow band (GPDA-S). GPDA-F was negative in all healthy persons as well as in the patients with benign liver filling defects, while it was positive in 85.3% cases of PHC. Liver cirrhosis, chronic hepatitis, extrahepatic carcinoma and metastatic liver carcinoma had low positive rates. GPDA-F was positively correlated with serum total GPDA activities, but had no correlation with AFP and size of the tumors. There was the correlation between GPDA-F and ALT in benign liver diseases, but no correlation between GPDA-F and ALT in PHC. Serial measurements of serum GPDA-F showed that GPDA-F was persistently positive in PHC but might change into negative in benign liver diseases. Dynamic determination of GPDA-F might be helpful to differentiate true positive of PHC from false positive of benign liver diseases.
  
  
  CONCLUSIONS
  GPDA-F is a new serum marker of PHC. Measurement of serum GPDA-F is of value for the diagnosis of PHC, especially for those at early stage or with negative AFP.
authors.affiliation: Department of Gastroenterology, Affiliated Hospital of Nantong Medical College, Nantong, Jiangsu Province, 226001, China.
authors.forename: M
authors.initials: M
authors.lastname: Li
authors.forename: R
authors.initials: R
authors.lastname: Ni
authors.forename: J
authors.initials: J
authors.lastname: Huang
authors.forename: M
authors.initials: M
authors.lastname: Xiao
authors.forename: H
authors.initials: H
authors.lastname: Zhang
authors.forename: Q
authors.initials: Q
authors.lastname: Wei
authors.forename: F
authors.initials: F
authors.lastname: Jiang
authors.forename: X
authors.initials: X
authors.lastname: Meng
mesh_terms: D000410:Alanine Transaminase / Q000097:blood; D000626:Aminopeptidases / Q000097:blood*; D006528:Carcinoma, Hepatocellular / Q000175:diagnosis* / Q000201:enzymology; D006801:Humans; D007527:Isoenzymes / Q000097:blood*; D008113:Liver Neoplasms / Q000175:diagnosis* / Q000201:enzymology
chemical_list: D007527:Isoenzymes; D000410:Alanine Transaminase; D000626:Aminopeptidases; C018085:glycylproline dipeptidyl aminopeptidase