title: Tissue inhibitor of metalloproteinase-3 induces a Fas-associated death domain-dependent type II apoptotic pathway.
abstract: Tissue inhibitors of metalloproteinases (TIMPs) are important regulators of matrix metalloproteinase (MMP) and adamalysin metalloproteinase activity. We previously reported that overexpression of TIMP-3 inhibits MMPs and induces apoptotic cell death in a variety of cell types and demonstrated that apoptosis is mediated through the N terminus of TIMP-3, which harbors the MMP inhibitory domain. However, little is known about the mechanisms underlying TIMP-3-induced apoptosis. Here we demonstrate that overexpression of TIMP-3 induced activation of initiator caspase-8 and -9 and promoted caspase-mediated cleavage of the death substrates poly(ADP-ribose) polymerase and focal adhesion kinase. Furthermore, TIMP-3 induced mitochondrial activation as demonstrated by loss of mitochondrial membrane potential and release of cytochrome c. Intervention studies demonstrated that overexpression of Bcl-2, the anti-apoptotic mitochondrial membrane protein, or CrmA, a viral serpin inhibitor of caspase-8, completely inhibited TIMP-3-induced apoptosis. Furthermore, a dominant-negative Fas-associated death domain mutant inhibited TIMP-3-induced death substrate cleavage and apoptotic death. Taken together, these results indicate that TIMP-3 overexpression induces a type II apoptotic pathway initiated via a Fas-associated death domain-dependent mechanism.
authors.affiliation: Bristol Heart Institute, Level 7, Bristol Royal Infirmary, University of Bristol, Bristol BS2 8HW, United Kingdom. Mark.bond@bris.ac.uk
authors.forename: Mark
authors.initials: M
authors.lastname: Bond
authors.forename: Gillian
authors.initials: G
authors.lastname: Murphy
authors.forename: Martin R
authors.initials: MR
authors.lastname: Bennett
authors.forename: Andrew C
authors.initials: AC
authors.lastname: Newby
authors.forename: Andrew H
authors.initials: AH
authors.lastname: Baker
mesh_terms: D000256:Adenoviridae / Q000235:genetics; D000818:Animals; D001011:Aorta / Q000166:cytology; D017209:Apoptosis; D015153:Blotting, Western; D053181:Caspase 8; D053453:Caspase 9; D020169:Caspases / Q000378:metabolism; D002460:Cell Line; D002478:Cells, Cultured; D003574:Cytochrome c Group / Q000378:metabolism; D004797:Enzyme-Linked Immunosorbent Assay; D051417:Focal Adhesion Kinase 1; D051416:Focal Adhesion Protein-Tyrosine Kinases; D005799:Genes, Dominant; D006367:HeLa Cells; D006801:Humans; D008564:Membrane Potentials; D008928:Mitochondria / Q000378:metabolism; D011065:Poly(ADP-ribose) Polymerases / Q000378:metabolism; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D011505:Protein-Tyrosine Kinases / Q000378:metabolism; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism; D051381:Rats; D015843:Serpins / Q000378:metabolism; D019717:Tissue Inhibitor of Metalloproteinase-3 / Q000378:metabolism*; D014764:Viral Proteins; D019014:fas Receptor / Q000378:metabolism*
chemical_list: D003574:Cytochrome c Group; D019253:Proto-Oncogene Proteins c-bcl-2; D015843:Serpins; D019717:Tissue Inhibitor of Metalloproteinase-3; D014764:Viral Proteins; D019014:fas Receptor; C074641:interleukin-1beta-converting enzyme inhibitor; D011065:Poly(ADP-ribose) Polymerases; D011505:Protein-Tyrosine Kinases; D051417:Focal Adhesion Kinase 1; D051416:Focal Adhesion Protein-Tyrosine Kinases; C496050:PTK2 protein, human; C496052:Ptk2 protein, rat; C505530:CASP8 protein, human; C506433:CASP9 protein, human; C505528:Casp8 protein, rat; C506435:Casp9 protein, rat; D053181:Caspase 8; D053453:Caspase 9; D020169:Caspases