title: Identification of CD63 as a tissue inhibitor of metalloproteinase-1 interacting cell surface protein.
abstract: This study identified CD63, a member of the tetraspanin family, as a TIMP-1 interacting protein by yeast two-hybrid screening. Immunoprecipitation and confocal microscopic analysis confirmed CD63 interactions with TIMP-1, integrin beta1, and their co-localizations on the cell surface of human breast epithelial MCF10A cells. TIMP-1 expression correlated with the level of active integrin beta1 on the cell surface independent of cell adhesion. While MCF10A cells within a three-dimensional (3D) matrigel matrix form polarized acinar-like structures, TIMP-1 overexpression disrupted breast epithelial cell polarization and inhibited caspase-mediated apoptosis in centrally located cells, necessary for the formation and maintenance of the hollow acinar-like structures. Small hairpin RNA (shRNA)-mediated CD63 downregulation effectively reduced TIMP-1 binding to the cell surface, TIMP-1 co-localization with integrin beta1, and consequently reversed TIMP-1-mediated integrin beta1 activation, cell survival signaling and apoptosis inhibition. CD63 downregulation also restored polarization and apoptosis of TIMP-1 overexpressing MCF10A cells within a 3D-matrigel matrix. Taken together, the present study identified CD63 as a cell surface binding partner for TIMP-1, regulating cell survival and polarization via TIMP-1 modulation of tetraspanin/integrin signaling complex.
authors.affiliation: Department of Pathology, Barbara Ann Karmanos Cancer Institute, Wayne State University School of Medicine, Detroit, MI 48201, USA.
authors.forename: Ki-Kyung
authors.initials: KK
authors.lastname: Jung
authors.forename: Xu-Wen
authors.initials: XW
authors.lastname: Liu
authors.forename: Rosemarie
authors.initials: R
authors.lastname: Chirco
authors.forename: Rafael
authors.initials: R
authors.lastname: Fridman
authors.forename: Hyeong-Reh Choi
authors.initials: HR
authors.lastname: Kim
mesh_terms: D015703:Antigens, CD / Q000378:metabolism / Q000502:physiology*; D017209:Apoptosis; D002448:Cell Adhesion; D002460:Cell Line; D002462:Cell Membrane / Q000378:metabolism; D016764:Cell Polarity; D002470:Cell Survival; D015536:Down-Regulation; D004847:Epithelial Cells / Q000166:cytology / Q000378:metabolism; D015723:Gene Library; D006801:Humans; D019012:Integrin beta1 / Q000378:metabolism*; D042361:Mammary Glands, Human / Q000166:cytology; D008565:Membrane Proteins / Q000378:metabolism*; D010980:Platelet Membrane Glycoproteins / Q000378:metabolism / Q000502:physiology*; D011485:Protein Binding; D015398:Signal Transduction; D060149:Tetraspanin 30; D019715:Tissue Inhibitor of Metalloproteinase-1 / Q000378:metabolism*; D020798:Two-Hybrid System Techniques
chemical_list: D015703:Antigens, CD; C554586:CD63 protein, human; D019012:Integrin beta1; D008565:Membrane Proteins; D010980:Platelet Membrane Glycoproteins; D060149:Tetraspanin 30; D019715:Tissue Inhibitor of Metalloproteinase-1