Urokinase directly activates matrix metalloproteinases-9: a potential role in glioblastoma invasion.
Previous reports showed that urokinase plasminogen activator (uPA) converts plasminogen to plasmin which then activates matrix metalloproteinases (MMPs). Here, we report that uPA directly cleaved pro-MMP-9 in a time-dependent manner at both C- and N-terminus and generated two gelatinolytic bands. uPA-activated-MMP-9 efficiently degraded fibronectin and blocked by uPA inhibitor B428 and recombinant tissue inhibitor of metalloproteinase-1 (TIMP-1). B428 inhibited basal and PMA-induced active MMP-9 in glioblastomas (GBM) U1242 cell media as well as cell invasion in vitro. A combination of MMP-9 and uPA antibodies more significantly inhibited U1242 cell invasion than uPA or MMP-9 antibody alone. Both uPA and MMP-9 were highly expressed in U1242 cell and GBM patient specimens. Furthermore, two active MMP-9 fragments with identical molecular weights to the uPA-activated MMP-9 products were detected in GBM patient specimens. These results suggest that uPA-mediated direct activation of MMP-9 may promote GBM cell invasion.
Zhao
Yunge
Y
Department of Pathology, University of Virginia, 415 Lane Road, MR5 Rm3332, Charlottesville, VA 22908, USA.
Lyons
Charles E
CE
Xiao
Aizhen
A
Templeton
Dennis J
DJ
Sang
Qingxiang Amy
QA
Brew
Keith
K
Hussaini
Isa M
IM
D000209:Acute-Phase Proteins / Q000378:metabolism; D001932:Brain Neoplasms / Q000201:enzymology / Q000473:pathology*; D004789:Enzyme Activation; D005353:Fibronectins / Q000737:chemistry; D005780:Gelatin / Q000737:chemistry; D005909:Glioblastoma / Q000201:enzymology / Q000473:pathology*; D006801:Humans; D000071068:Lipocalin-2; D054834:Lipocalins / Q000378:metabolism; D020780:Matrix Metalloproteinase 9 / Q000737:chemistry / Q000378:metabolism*; D009361:Neoplasm Invasiveness; D011518:Proto-Oncogene Proteins / Q000378:metabolism; D019715:Tissue Inhibitor of Metalloproteinase-1 / Q000378:metabolism; D014568:Urokinase-Type Plasminogen Activator / Q000737:chemistry / Q000378:metabolism*
D000209:Acute-Phase Proteins; D005353:Fibronectins; C489506:LCN2 protein, human; D000071068:Lipocalin-2; D054834:Lipocalins; D011518:Proto-Oncogene Proteins; D019715:Tissue Inhibitor of Metalloproteinase-1; D005780:Gelatin; D014568:Urokinase-Type Plasminogen Activator; D020780:Matrix Metalloproteinase 9