Interleukin-1 beta and transforming growth factor-alpha/epidermal growth factor induce expression of M(r) 95,000 type IV collagenase/gelatinase and interstitial fibroblast-type collagenase by rat mucosal keratinocytes.
Rat mucosal keratinocytes serially propagated under permanently serum-free conditions responded to interleukin (IL)-1 beta/IL-alpha and to transforming growth factor (TGF)-alpha/epidermal growth factor (EGF) (as well as to 12-O-tetradecanoylphorbol-13-acetate (TPA)) by upregulation of M(r) 95,000 gelatinase (MMP-9) (M(r) 95K GL) and fibroblast-type collagenase (MMP-1) (FIB-CL), whereas control cells expressed barely detectable levels of either of these enzymes. The cells secreted 8-10 micrograms/10(6) cells/day (M(r) 95K GL) and 2-3 micrograms/10(6) cells/day (FIB-CL) of enzyme protein for at least 24 h when maximally induced. This level was attained only after a 24-h lag period, and the earliest emergence of enzyme protein in the culture medium required 10-14 h. IL-1 beta was by far the most potent cytokine with maximal effect already at 10(-10) M, whereas IL-1 alpha, TGF-alpha, and EGF required 20-100-fold higher concentrations. Pretreatment of the cells with TPA (10(-7) M) abolished the subsequent response to IL-1 beta, TGF-alpha, and EGF and at the same time resulted in > 90% reduction of cytosolic protein kinase C activity. Surprisingly, staurosporine, a potent kinase inhibitor, not only failed to block growth factor/cytokine responses but itself stimulated expression of the enzymes at a magnitude comparable to TPA. The inducing effect of TGF-alpha/EGF was down-regulated by 70-85% by 10(-7) M dexamethasone. Dexamethasone was less effective in ablating the IL-1 beta response yielding 60% reduction M(r) 95K GL and little or no reduction of FIB-CL. Dexamethasone also failed to block the TPA response.
Department of Oral Biology, University of Alabama School of Dentistry, University of Alabama, Birmingham 35294.
J G
JG
Lyons
B
B
Birkedal-Hansen
M C
MC
Pierson
J M
JM
Whitelock
H
H
Birkedal-Hansen
D000470:Alkaloids / Q000494:pharmacology; D000818:Animals; D002460:Cell Line; D017364:Collagenases / Q000378:metabolism*; D003907:Dexamethasone / Q000494:pharmacology; D010450:Endopeptidases / Q000378:metabolism*; D004790:Enzyme Induction; D004797:Enzyme-Linked Immunosorbent Assay; D004815:Epidermal Growth Factor / Q000494:pharmacology*; D005347:Fibroblasts / Q000201:enzymology; D018093:Gelatinases; D007375:Interleukin-1 / Q000494:pharmacology*; D015603:Keratinocytes / Q000201:enzymology*; D008325:Mammary Neoplasms, Experimental; D008970:Molecular Weight; D009061:Mouth Mucosa / Q000201:enzymology; D011493:Protein Kinase C / Q000378:metabolism; D051381:Rats; D019311:Staurosporine; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D016211:Transforming Growth Factor alpha / Q000494:pharmacology*; D014407:Tumor Cells, Cultured
D000470:Alkaloids; D007375:Interleukin-1; D016211:Transforming Growth Factor alpha; D004815:Epidermal Growth Factor; D003907:Dexamethasone; D011493:Protein Kinase C; D010450:Endopeptidases; D017364:Collagenases; D018093:Gelatinases; D019311:Staurosporine; D013755:Tetradecanoylphorbol Acetate