Activation of tumor cell matrix metalloproteinase-2 by neutrophil proteinases requires expression of membrane-type 1 matrix metalloproteinase.
BACKGROUND
Matrix metalloproteinase-2 (MMP-2), an enzyme involved in tumor invasion, is secreted as an inactive proenzyme and requires interaction with membrane-type 1 MMP (MT1-MMP) for activation. We have previously demonstrated that polymorphonuclear neutrophils (PMNs) release a soluble factor(s) that activates pro-MMP-2. Therefore, we tested the hypothesis that PMN-derived proteinases act in concert with MT1-MMP to activate pro-MMP-2.


METHODS
Human HT-1080 cells transfected with MT1-MMP cDNA (HT-SE) or the corresponding antisense cDNA (HT-AS) or an empty vector (HT-V), which expressed differing levels of MT1-MMP, were incubated with serum-free, human PMN-conditioned medium with or without proteinase inhibitors. The culture supernatants were analyzed by gelatin zymography.


RESULTS
Ht-1080 cells expressing basal (HT-V) or low levels (HT-AS) of MT1-MMP secreted MMP-2 in proenzyme from (72 kd). Ht-1080 cells with high levels of MT1-MMP (HT-SE) secreted pro MMP-2 and a 68 kd intermediate activation product. Addition of PMN-conditioned medium to either HT-SE or HT-V clones resulted in dose-dependent generation of active, 62 kd MMP-2. In contrast, when PMN-conditioned medium was added to HT-AS clones, no MMP-2 activation occurred.


CONCLUSIONS
PMN-derived serine proteinases act in concert with MT1-MMP to activate proMMP-2. This finding indicates a potential role for inflammatory cells in promoting extracellular matrix breakdown during tumor invasion.
Schwartz
J D
JD
New York University School of Medicine, Department of Surgery, S. Arthur Localio Surgical Research Laboratory, NY, USA.
Shamamian
P
P
Monea
S
S
Whiting
D
D
Marcus
S G
SG
Galloway
A C
AC
Mignatti
P
P
D007611:Aprotinin / Q000494:pharmacology; D017364:Collagenases / Q000378:metabolism*; D015853:Cysteine Proteinase Inhibitors / Q000494:pharmacology; D010450:Endopeptidases / Q000378:metabolism; D004789:Enzyme Activation / Q000276:immunology; D004792:Enzyme Precursors / Q000378:metabolism; D005354:Fibrosarcoma; D018093:Gelatinases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D006801:Humans; D007930:Leucine / Q000031:analogs & derivatives / Q000494:pharmacology; D020781:Matrix Metalloproteinase 1; D020778:Matrix Metalloproteinase 2; D020780:Matrix Metalloproteinase 9; D061965:Matrix Metalloproteinase Inhibitors; D008666:Metalloendopeptidases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D009361:Neoplasm Invasiveness; D009504:Neutrophils / Q000201:enzymology*; D010436:Pepstatins / Q000494:pharmacology; D010649:Phenylalanine / Q000031:analogs & derivatives / Q000494:pharmacology; D011480:Protease Inhibitors / Q000494:pharmacology; D015842:Serine Proteinase Inhibitors / Q000494:pharmacology; D013876:Thiophenes / Q000494:pharmacology; D014162:Transfection; D014407:Tumor Cells, Cultured / Q000187:drug effects / Q000201:enzymology; D000515:alpha 1-Antitrypsin / Q000494:pharmacology
D015853:Cysteine Proteinase Inhibitors; D004792:Enzyme Precursors; D061965:Matrix Metalloproteinase Inhibitors; D010436:Pepstatins; D011480:Protease Inhibitors; D015842:Serine Proteinase Inhibitors; D013876:Thiophenes; D000515:alpha 1-Antitrypsin; C014195:Streptomyces pepsin inhibitor; D010649:Phenylalanine; D007611:Aprotinin; C080985:batimastat; D010450:Endopeptidases; D017364:Collagenases; D018093:Gelatinases; D008666:Metalloendopeptidases; D020778:Matrix Metalloproteinase 2; D020780:Matrix Metalloproteinase 9; D020781:Matrix Metalloproteinase 1; D007930:Leucine; C024974:E 64; C031375:pepstatin