Plasminogen activators and tumor development in the human colon: activity levels in normal mucosa, @entity6523 , and XXXX .

@entity1127 @entity5932 @entity189 @entity6523 @entity14 @entity3479 @entity420 @entity2290
Malignant changes are often accompanied by alterations in activity and composition of the plasminogen activators (PA). To study the relationship between PA expression and the development of @entity14 , we determined @entity2290 ( @entity2290 ) and @entity3479 ( @entity3479 ) activity in normal mucosa (n = 80), @entity6523 (n = 76), and @entity420 (n = 71) of the colon. Tissues obtained from surgical resection or polypectomy were analyzed for @entity3479 and @entity2290 activity in a specific enzymatic assay using plasminogen, a chromogenic substrate, and selective quenching with monospecific antibodies to both activators. The plasminogen activator activities were found to be changed in @entity420 as @entity5932 . The relative contribution of @entity2290 (expressed as percentage of @entity2290 ) was raised from 6 to 50% for, respectively, normal mucosa and @entity420 . This change could be attributed to a 3-fold decrease in @entity3479 activity and a 5-fold increase in @entity2290 activity in the @entity189 . @entity6523 as a group showed percentages of @entity2290 [20.2 +/- 1.3 (SE)] which were intermediate as well as significantly different (P less than 0.001) from those of normal mucosa and @entity420 . This observation was strengthened by a gradual rise in the relative contribution of @entity2290 in four resection specimens containing both @entity6523 and @entity420 . Zymography showed the presence of minor quantities of PA-PA inhibitor complexes in the tissue extracts studied. The present study shows that the sequence of normal mucosa-adenomatous @entity1127 in the colon is associated with a parallel change in plasminogen activator activity. Thus, change in the regulation of plasminogen activator activity is an early event in the development of @entity14 .
