title: Transforming growth factor-beta - and tumor necrosis factor-alpha -mediated induction and proteolytic activation of MMP-9 in human skin.
abstract: Both cytokines and matrix metalloproteinases (MMPs) are active during physiologic and pathologic processes such as cancer metastasis and wound repair. We have systematically studied cytokine-mediated MMP regulation. Cytokine-mediated proteinase induction and activation were initially investigated in organ-cultured human skin followed by determination of underlying cellular and molecular mechanisms using isolated skin cells. In this report we demonstrate that tumor necrosis factor-alpha (TNF-alpha) and transforming growth factor-beta (TGF-beta) synergistically induce pro-MMP-9 in human skin as well as isolated dermal fibroblasts and epidermal keratinocytes. Furthermore, TNF-alpha promotes proteolytic activation of pro-MMP-9 by conversion of the 92-kDa pro-MMP-9 to the 82-kDa active enzyme. This activation occurred only in skin organ culture and not by either isolated fibroblasts or keratinocyte, although the pro-MMP-9 activation could be measured in a cell-free system derived from TNF-alpha-activated skin. The cytokine-mediated induction of pro-MMP-9 in dermal fibroblasts was evident by increased mRNA. At the transcription level, we examined the cytokine-mediated transactivation of the 5'-region promoter of the human MMP-9 in dermal fibroblasts. The results demonstrated that TNF-alpha and TGF-beta could independently stimulate the 5'-flanking 670-base pair promoter. A TGF-beta-response element (-474) and an NF-kappaB-binding site (-601) were identified to be the cis-elements for TGF-beta or TNF-alpha activation, respectively. Taken together, these findings suggest a specific mechanism whereby multiple cytokines can regulate MMP-9 expression/activation in the cells of human skin. These results imply roles for these cytokines in the regulation of MMP-9 in physiologic and pathologic tissue remodeling.
authors: Division of Plastic and Reconstructive Surgery, University of Southern California School of Medicine, Los Angeles, California 90033, USA.
authors: Y P
authors: YP
authors: Han
authors: T L
authors: TL
authors: Tuan
authors: M
authors: M
authors: Hughes
authors: H
authors: H
authors: Wu
authors: W L
authors: WL
authors: Garner
mesh_terms: D001483:Base Sequence; D017364:Collagenases / Q000378:metabolism; D017931:DNA Primers; D004305:Dose-Response Relationship, Drug; D004789:Enzyme Activation; D004792:Enzyme Precursors / Q000378:metabolism; D006801:Humans; D006868:Hydrolysis; D066298:In Vitro Techniques; D015603:Keratinocytes / Q000187:drug effects / Q000201:enzymology; D007700:Kinetics; D020780:Matrix Metalloproteinase 9 / Q000096:biosynthesis* / Q000235:genetics / Q000378:metabolism; D011401:Promoter Regions, Genetic; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012867:Skin / Q000187:drug effects* / Q000201:enzymology; D015533:Transcriptional Activation / Q000187:drug effects; D016212:Transforming Growth Factor beta / Q000494:pharmacology*; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology*
chemical_list: D017931:DNA Primers; D004792:Enzyme Precursors; D016212:Transforming Growth Factor beta; D014409:Tumor Necrosis Factor-alpha; D017364:Collagenases; C120487:pro-matrix metalloproteinase 9; D020780:Matrix Metalloproteinase 9