There is abundant evidence that the urokinase-type plasminogen activator (uPA), its inhibitors PAI-1 and PAI-2 (plasminogen activator inhibitor type-1 and type-2) and its cells surface receptor (uPA-R, CD87) play a fundamental role in tumor invasion and metastasis and are of significant prognostic significance for many tumor types.
Tumour-associated proteinases, matrix metalloproteinases and plasminogen activators are reported to be involved in pancreatic cancer invasion and metastasis.
The urokinase plasminogen activator (uPA) is regarded as the crucial trigger for plasmin generation, which is involved in several diseases especially for neoplasm metastasis.
It is a specific cell surface receptor for its ligand uPA, which catalyzes the formation of plasmin from plasminogen, thereby activating the proteolytic cascade that contributes to the breakdown of extracellular matrix, a key step in cancer metastasis.
We investigated the role of the fibrinolytic enzyme plasmin in tumor cell migration across brain endothelial cells and growth of brain metastases in an experimental metastatic melanoma model.
The Plasminogen Activation (PA) system, including urokinase plasminogen activator (uPA), its receptor and its inhibitor, plasminogen activator inhibitor type 1(PAI-1), also plays a key role in cancer invasion and metastasis, either through proteolytic degradation or by non-proteolytic modulation of cell adhesion and migration.
These data suggest that the invasive and metastatic potential of human large-cell lung carcinoma cell lines is associated with differential expressions of the components of the plasminogen activator system and that the determination of these components may be used as a marker for judging clinically the possibility of tumor metastasis as well as the prognoses of patients.
Annexin A2 is reported to be a powerful activator of plasminogen and, therefore, is implicated in many normal and pathological processes such as haemostasis and metastasis.
PAI-1 inhibits the activation of uPA (which converts plasminogen to plasmin), and is involved in cancer invasion and metastasis, by remodeling the extracellular matrix (ECM) through regulating plasmin.
It is a specific cell surface receptor for its ligand, urokinase-type plasminogen activator, which catalyzes the formation of plasmin from plasminogen to generate the proteolytic cascade and leads to the breakdown of the extracellular matrix. uPAR has been shown to correlate with a propensity to tumor invasion and metastasis in several types of non-central nervous system tumors.
The serine protease urokinase plasminogen activator (uPA) and the plasminogen activator inhibitor type-1 (PAI-1) play an important role in tumour invasion and metastasis.
Because no data are available on the involvement of the plasmin activation system in matrix degradation by thyroid carcinoma, the present study was performed using follicular thyroid carcinoma cell lines obtained from a primary tumor (FTC-133) and metastases (FTC-236 and FTC-238) of one patient.
Streptokinase is a virulence factor of streptococci and acts as a plasminogen activator to generate the serine protease plasmin which promotes bacterial metastasis.
There is abundant evidence that the plasminogen activator (PA) system with its key components uPA (urokinase-type plasminogen activator), its cell surface receptor uPA-R (CD87) and its inhibitor PAI-1 plays a key role in tumour invasion and metastasis.
These results suggest involvement of the PA/plasmin system in IGF-induced migration and indicate important roles these systems may have in RMS metastasis.
Plasmin, the major fibrinolytic enzyme in blood, also participates in a number of physiologic functions involving protein processing and tissue remodelling, and may play an important role in tumor invasion and metastasis.
These findings suggest that VEGF-B may contribute to tumour progression by a non-angiogenic mechanism, possibly by increasing plasminogen activators and hence metastasis, as has been described in vitro.