title: Heparanase induces tissue factor pathway inhibitor expression and extracellular accumulation in endothelial and tumor cells.
abstract: Heparanase activity is implicated in cell invasion, tumor metastasis and angiogenesis. Recently, we have reported that heparanase stimulates tissue factor (TF) expression in endothelial and cancer cells, resulting in elevation of coagulation activity. We hypothesized that heparanase regulates other coagulation modulators, and examined the expression and localization of tissue factor pathway inhibitor (TFPI) following heparanase over-expression or exogenous addition. Primary human umbilical vein endothelial cells (HUVEC) and human tumor-derived cell lines were incubated with heparanase, or were stably transfected with heparanase gene-constructs, and TFPI expression and secretion were examined. Heparanase over-expression or exogenous addition stimulated TFPI expression by 2-3 folds. TFPI accumulation in the cell culture medium exceeded in magnitude the observed induction of TFPI gene transcription reaching 5- to 6-fold increase. Extracellular accumulation of TFPI was evident already 60 min following heparanase addition, prior to TFPI protein induction, and correlated with increased coagulation activity. This effect was found to be independent of heparanase enzymatic activity and interaction with heparan-sulfate, and correlated with reduced TFPI levels on the cell surface. Data were verified in heparanase transgenic mice tissues and plasma. Interaction between heparanase and TFPI was evident by co-immunoprecipitation. Interaction of heparanase with TFPI resulted in its displacement from the surface of the vascular endothelium and in increased pro-coagulant activity. Thus, heparanase facilitates blood coagulation on the cell surface by two independent mechanisms: dissociation of TFPI from the vascular surface shortly after local elevation of heparanase levels, and subsequent induction of TF expression.
authors.affiliation: Cancer and Vascular Biology Research Center, The Bruce Rappaport Faculty of Medicine, Technion, Haifa 31096, Israel.
authors.forename: Yona
authors.initials: Y
authors.lastname: Nadir
authors.forename: Benjamin
authors.initials: B
authors.lastname: Brenner
authors.forename: Sveta
authors.initials: S
authors.lastname: Gingis-Velitski
authors.forename: Flonia
authors.initials: F
authors.lastname: Levy-Adam
authors.forename: Neta
authors.initials: N
authors.lastname: Ilan
authors.forename: Eyal
authors.initials: E
authors.lastname: Zcharia
authors.forename: Erez
authors.initials: E
authors.lastname: Nadir
authors.forename: Israel
authors.initials: I
authors.lastname: Vlodavsky
mesh_terms: D000818:Animals; D001777:Blood Coagulation / Q000235:genetics; D045744:Cell Line, Tumor; D002462:Cell Membrane / Q000201:enzymology / Q000378:metabolism*; D002478:Cells, Cultured; D042783:Endothelial Cells / Q000201:enzymology / Q000378:metabolism*; D005966:Glucuronidase / Q000235:genetics / Q000378:metabolism*; D006497:Heparan Sulfate / Q000378:metabolism; D006801:Humans; D008074:Lipoproteins / Q000235:genetics / Q000378:metabolism*; D051379:Mice; D008822:Mice, Transgenic; D009369:Neoplasms / Q000201:enzymology / Q000235:genetics / Q000378:metabolism*; D011485:Protein Binding; D012333:RNA, Messenger / Q000378:metabolism; D011994:Recombinant Proteins / Q000378:metabolism; D013925:Thromboplastin / Q000378:metabolism; D013997:Time Factors; D014158:Transcription, Genetic; D014162:Transfection; D015854:Up-Regulation; D000099175:Heparanase
chemical_list: D005966:Glucuronidase; D006497:Heparan Sulfate; D008074:Lipoproteins; D012333:RNA, Messenger; D011994:Recombinant Proteins; D013925:Thromboplastin; D000099175:Heparanase; C051928:lipoprotein-associated coagulation inhibitor