Mechanisms of hepatocyte growth factor stimulation of keratinocyte metalloproteinase production.
Matrix metalloproteinases participate in normal physiologic processes; however, their overproduction has been associated with connective tissue destruction in a variety of pathological states. Migrating basal keratinocytes transiently express collagenase-1 during normal cutaneous reepithelialization. However, the overexpression of both collagenase-1 and stromelysin-1 has been associated with the pathogenesis of chronic nonhealing ulcers. Aberrant expression of metalloproteinases in inflammation is mediated, at least in part, by soluble factors. Since hepatocyte growth factor/scatter factor (HGF/SF) has been reported to promote keratinocyte migration and proliferation, key events in wound repair, and since HGF/SF is produced by dermal fibroblasts and its c-Met receptor is expressed by basal keratinocytes in wounded skin, we have studied the effects of HGF/SF upon keratinocyte metalloproteinase expression. We have found that HGF/SF can stimulate keratinocyte collagenase-1 and stromelysin-1 production in a dose-dependent and matrix-dependent manner. Expression of 92-kDa gelatinase was not affected by HGF/SF. We determined that HGF/SF regulation of collagenase-1 expression is transcriptionally mediated and requires tyrosine kinase and protein kinase C activaties. HGF/NK1, a naturally occurring, truncated form of HGF/SF, also stimulates collagenase-1 production, but much less efficiently than does the parent molecule. However, HGF/NK2, another HGF/SF splice variant, as well as heparin, potently inhibit HGF/SF-induced collagenase-1 synthesis. These results indicate that HGF/SF and its naturally occurring splice variants have diverse biological effects on keratinocytes and suggest an additional mechanism whereby HGF/SF may regulate keratinocyte function during wound repair.
Dunsmore
S E
SE
Department of Medicine (Dermatology), Washington University School of Medicine, St. Louis, Missouri 63110, USA.
Rubin
J S
JS
Kovacs
S O
SO
Chedid
M
M
Parks
W C
WC
Welgus
H G
HG
D000328:Adult; D002478:Cells, Cultured; D017364:Collagenases / Q000096:biosynthesis*; D006493:Heparin / Q000494:pharmacology; D017228:Hepatocyte Growth Factor / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D006801:Humans; D015603:Keratinocytes / Q000187:drug effects* / Q000201:enzymology; D019278:Matrix Metalloproteinase 3 / Q000096:biosynthesis*; D011493:Protein Kinase C / Q000378:metabolism; D011505:Protein-Tyrosine Kinases / Q000378:metabolism
D017228:Hepatocyte Growth Factor; D006493:Heparin; D011505:Protein-Tyrosine Kinases; D011493:Protein Kinase C; D017364:Collagenases; D019278:Matrix Metalloproteinase 3