title: Shedding of membrane vesicles by tumor and endothelial cells.
abstract: Shedding of membrane vesicles is a vital phenomenon frequently observed in tumor cells and suggested to be involved in several aspects of tumor progression. Our previous studies have shown that human breast tumor cells rapidly shed membrane vesicles containing matrix metalloproteinases (MMPs). In this study we present that human umbilical vein endothelial cells (HUVEC) as well as different tumor cell lines (human ovarian cancer, CABA I and A2780, and hepatocarcinoma cell line, SK-Hep 1) shed vesicles in the extracellular medium. These vesicles carry MMPs and their inhibitors TIMPs. We conclude that tumor and endothelial cells shed MMP-containing vesicles and this may represent a mechanism for regulating focalized proteolytic activity and a way to interact with microenvironment during tumor angiogenesis.
authors.affiliation: Department of Experimental Medicine, University of L'Aquila, L'Aquila, Italy. dolo@univaq.it
authors.forename: V
authors.initials: V
authors.lastname: Dolo
authors.forename: S
authors.initials: S
authors.lastname: D'Ascenzo
authors.forename: I
authors.initials: I
authors.lastname: Giusti
authors.forename: D
authors.initials: D
authors.lastname: Millimaggi
authors.forename: G
authors.initials: G
authors.lastname: Taraboletti
authors.forename: A
authors.initials: A
authors.lastname: Pavan
mesh_terms: D002277:Carcinoma / Q000098:blood supply / Q000503:physiopathology / Q000648:ultrastructure; D006528:Carcinoma, Hepatocellular / Q000098:blood supply / Q000503:physiopathology / Q000648:ultrastructure; D045744:Cell Line, Tumor; D002462:Cell Membrane / Q000502:physiology / Q000648:ultrastructure*; D042783:Endothelial Cells / Q000502:physiology / Q000648:ultrastructure*; D005089:Exocytosis / Q000502:physiology; D005110:Extracellular Space / Q000378:metabolism; D005260:Female; D006801:Humans; D020782:Matrix Metalloproteinases / Q000378:metabolism; D008855:Microscopy, Electron, Scanning; D009361:Neoplasm Invasiveness / Q000503:physiopathology / Q000648:ultrastructure*; D009369:Neoplasms / Q000098:blood supply* / Q000503:physiopathology / Q000648:ultrastructure; D009389:Neovascularization, Pathologic / Q000473:pathology* / Q000503:physiopathology; D010051:Ovarian Neoplasms / Q000098:blood supply / Q000503:physiopathology / Q000648:ultrastructure; D022142:Secretory Vesicles / Q000502:physiology / Q000648:ultrastructure*; D019714:Tissue Inhibitor of Metalloproteinases / Q000378:metabolism; D014471:Umbilical Veins
chemical_list: D019714:Tissue Inhibitor of Metalloproteinases; D020782:Matrix Metalloproteinases