title: Tumor promoter TPA stimulates MMP-9 secretion from human keratinocytes by activation of superoxide-producing NADPH oxidase.
abstract: Matrix metalloproteinase-9 (MMP-9) is involved in physiological tissue remodelling processes as well as in tumor invasion and metastasis. The tumor promoter 12-O-tetradecanoylphorbol-13-acetate (TPA) increases MMP-9 secretion from normal human epidermal keratinocytes (NHEK) in vivo and in vitro. Here we show that the flavoprotein inhibitor diphenyleneiodinium (DPI) and the NADPH oxidase inhibitor apocynin block TPA-induced MMP-9 secretion of NHEK in vitro. Furthermore, N-acetyl-L-cysteine and L-cysteine lowered TPA-induced MMP-9 secretion, suggesting an involvement of reactive oxygen species(ROS). TPA exerts its effect on MMP-9 gene expression and secretion via the superoxide-producing enzyme NADPH oxidase: TPA rapidly stimulates generation of superoxide anion as well as gene expression of two cytosolic NADPH oxidase subunits (p47-phox and p67-phox) after 2 h, which is followed by induction of MMP-9 gene expression after 4 h. Taken together, the novel finding herein is the TPA-induced MMP-9 secretion from normal human epidermal keratinocytes through a NADPH oxidase dependent pathway.
authors.affiliation: Biochemistry and Molecular Biology I, Heinrich-Heine-University Düsseldorf, Universitästrasse 1, D-40225 Düsseldorf, Germany.
authors.forename: Holger
authors.initials: H
authors.lastname: Steinbrenner
authors.forename: Maria C
authors.initials: MC
authors.lastname: Ramos
authors.forename: Dominik
authors.initials: D
authors.lastname: Stuhlmann
authors.forename: Dragana
authors.initials: D
authors.lastname: Mitic
authors.forename: Helmut
authors.initials: H
authors.lastname: Sies
authors.forename: Peter
authors.initials: P
authors.lastname: Brenneisen
mesh_terms: D001798:Blood Proteins / Q000378:metabolism; D002273:Carcinogens / Q000494:pharmacology*; D004789:Enzyme Activation / Q000187:drug effects*; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006801:Humans; D015603:Keratinocytes / Q000166:cytology / Q000187:drug effects* / Q000201:enzymology; D020780:Matrix Metalloproteinase 9 / Q000378:metabolism*; D019255:NADPH Oxidases / Q000378:metabolism*; D010750:Phosphoproteins / Q000378:metabolism; D013481:Superoxides / Q000378:metabolism*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology*
chemical_list: D001798:Blood Proteins; D002273:Carcinogens; D004791:Enzyme Inhibitors; D010750:Phosphoproteins; C079789:neutrophil cytosol factor 67K; C039077:platelet protein P47; D013481:Superoxides; D019255:NADPH Oxidases; D020780:Matrix Metalloproteinase 9; D013755:Tetradecanoylphorbol Acetate