Proteases of the plasminogen-plasminogen activator (PA) system play an important role in cancer @entity3 . We have examined the expression of these proteases and their cell surface receptors and inhibitors in @entity521 , a @entity5 that originates in cells of the neural crest and is the second most common @entity5 in @entity1 . This analysis was performed in seven established @entity1 cell lines and 20 primary @entity5 specimens. Urokinase PA and, in particular, tissue-type PA were expressed in cell lines and in @entity5 tissues; however, their levels of expression did not correlate with clinical stage. There was little evidence suggesting that @entity521 cells concentrate PA activity at their cell surface because urokinase-type PA receptor mRNA was detected in two cell lines and in 5 of 20 @entity5 samples by reverse transcription-PCR only. @entity10933 was absent in all cell lines and @entity5 tissue samples examined. However, @entity2289 , which was not expressed by the cell lines, was expressed by stromal cells and, specifically, endothelial cells in @entity5 tissue. By extending the analysis of @entity2289 expression in 64 primary @entity5 specimens, we found that high @entity2289 expression paradoxically correlated with metastatic stage and @entity5 recurrence. In vitro experiments indicated that the expression of @entity2289 by @entity1 microvascular endothelial cells was stimulated in the presence of SK-N-BE(2) @entity1 @entity521 cells and @entity521 culture medium. Recombinant @entity2289 also promoted SK-N-BE(2) cell detachment from @entity4732 and migration from @entity4732 toward fibronectin. From these data, we conclude that the up-regulation of @entity2289 expression in endothelial cells may promote rather than inhibit @entity3 in @entity521 .

The plasminogen-plasminogen activator (PA) system in XXXX : role of PA inhibitor-1 in @entity3 .

@entity1 :: ('9606', 'Species') :: ['children', 'human'] @entity2289 :: ('5054', 'Gene') :: ['PAI-1'] @entity5 :: ('MESH:D009369', 'Disease') :: ['tumor', 'solid tumor'] @entity521 :: ('MESH:D009447', 'Disease') :: ['neuroblastoma'] @entity10933 :: ('5055', 'Gene') :: ['PA inhibitor (PAI)-2'] @entity3 :: ('MESH:D009362', 'Disease') :: ['metastasis'] @entity4732 :: ('7448', 'Gene') :: ['vitronectin']
@entity521 :: (MESH:D009447,Disease) :: ['neuroblastoma']
