PURPOSE
We measured the gastric cancer tissue uPA and plasminogen activator inhibitor-1 (PAI-1) levels and compared them to those of the peripheral and portal blood levels to evaluate the correlation.
MATERIALS AND METHODS
Tissue uPA and PAI-1 levels were measured by ELISA assay (Monozyme, Netherland) in paired 85 normal and cancer tissues resected from gastric cancer patients. In 50 patients, blood uPA and PAI-1 levels were measured from pre- operative peripheral and portal blood, post-operative portal blood.
RESULTS
Gastric cancer tissue uPA and PAI-1 levels increased from the early stage. The elevated cancer-to-normal ratios of the uPA and PAI-1 were constant from stage I to IV. There were correlations of uPA between normal and cancer tissues (r2=0.38) and between peripheral and pre-resection portal blood level (r2=0.64). There were no correlations between tissue PAI-1 level and blood PAI-1 levels. However, there were correlations in PAI- 1/uPA ratio between cancer tissue and peripheral blood (r2=0.25), peripheral blood and pre- resection portal blood (r2=0.60).
CONCLUSION
Even if the cancer tissue levels of uPA and PAI-1 increased from the early stage of gastric cancer, only blood uPA level correlated with tissue uPA level. A modest correlation found in PAI-1/uPA ratio between cancer tissue and blood suggests applicability of blood PAI-1/uPA ratio in predicting tissue uPA, PAI-1 expression.