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Ramani V.C.,University of Alabama at Birmingham | Purushothaman A.,University of Alabama at Birmingham | Stewart M.D.,University of Alabama at Birmingham | Thompson C.A.,University of Alabama at Birmingham | And 3 more authors.
FEBS Journal | Year: 2013

Heparanase is an endoglucuronidase that cleaves heparan sulfate chains of proteoglycans. In many malignancies, high heparanase expression and activity correlate with an aggressive tumour phenotype. A major consequence of heparanase action in cancer is a robust up-regulation of growth factor expression and increased shedding of syndecan-1 (a transmembrane heparan sulfate proteoglycan). Substantial evidence indicates that heparanase and syndecan-1 work together to drive growth factor signalling and regulate cell behaviours that enhance tumour growth, dissemination, angiogenesis and osteolysis. Preclinical and clinical studies have demonstrated that therapies targeting the heparanase/syndecan-1 axis hold promise for blocking the aggressive behaviour of cancer. Levels of the heparan sulfate proteoglycan syndecan-1 and the heparan sulfate degrading enzyme heparanase are elevated in many cancers. Together these two molecules form a powerful axis that promotes an aggressive tumor phenotype. This review focuses on the mechanism of action of the heparanase/syndecan-1 axis and emerging therapeutic strategies to target this axis. © 2013 The Authors Journal compilation © 2013 FEBS. Source


Ostrovsky O.,Chaim Sheba Medical Center | Shimoni A.,Chaim Sheba Medical Center | Rand A.,Chaim Sheba Medical Center | Vlodavsky I.,Cancer and Vascular Biology Research Center | Nagler A.,Chaim Sheba Medical Center
Blood | Year: 2010

Graft-versus-host disease (GVHD) is the most common cause of nonrelapse mortality and morbidity after hematopoietic stem cell transplantation (HSCT). The welldocumented involvement of heparanase in the process of inflammation and autoimmunity led us to investigate an association between HPSE gene single-nucleotide polymorphisms (SNPs) and the risk of GVHD. The present study indicates a highly significant correlation of HPSE gene SNPs rs4693608 and rs4364254 and their combination with the risk of developing acute GVHD. Moreover, the study revealed that discrepancy between recipient and donor in these SNPs may elevate significantly the risk of acute GVHD. This association was statistically significant when the recipients possessed genotype combinations dictating higher levels of heparanase compared with their human leukocyte antigen (HLA)-matched donors. In addition, HPSE gene SNPs disclosed a correlation with extensive chronic GVHD, nonrelapse mortality, and overall survival. Our study indicates involvement of heparanase in the development of acute and extensive chronic GVHD. Moreover, it suggests a possible mechanism for the aggressive behavior of T lymphocytes leading to GVHD when the recipients possess genotype combinations that dictate high levels of heparanase mRNA compared with their HLA matched donors expressing low levels of heparanase. © 2010 by The American Society of Hematology. Source


Borsig L.,University of Zurich | Vlodavsky I.,Cancer and Vascular Biology Research Center | Ishai-Michaeli R.,Hebrew University of Jerusalem | Vismara E.,Polytechnic of Milan
Neoplasia | Year: 2011

Development of compounds that target both heparanase and selectins is emerging as a promising approach for cancer therapy. Selectins are vascular cell adhesion molecules that mediate tumor cell interactions with platelets, leukocytes, and the vascular endothelium. Heparanase is an endoglycosidase that degrades heparan sulfate in the tumor microenvironment, cell surfaces, and vessel wall. Acting together, these molecules facilitate tumor cell arrest, extravasation, and metastasis. Here, we report the preparation of novel semisynthetic sulfated tri annose C-C-linked dimers (STMCs) endowed with heparanase and selectin inhibitory activity. The P-selectin specificity of the STMC was defined by the anomeric linkage of the C-C bond. This STMC hexasaccharide is an effective inhibitor of P-selectin in vivo. We show that selective inhibition of heparanase attenuates metastasis in B16-BL6 melanoma cells, expressing high levels of this endoglycosidase, but has no effect on the metastasis of MC-38 carcinoma cells that express little or no heparanase activity. P-selectin-specific STMC attenuated metastasis in both animal models, indicating that inhibition of tumor cell interaction with the vascular endothelium is critical for cancer dissemination. Thus, the small size, the stability of the C-C bond, and the chemically defined structure of the newly generated STMCs make them superior to heparin derivatives and signify STMCs as valuabl candidates for further evaluation. © 2011 Neoplasia Press, Inc. All rights reserved. Source


Baker A.B.,University of Texas at Austin | Gibson W.J.,Harvard-MIT Division of Health Sciences and Technology | Kolachalama V.B.,Harvard-MIT Division of Health Sciences and Technology | Golomb M.,Harvard-MIT Division of Health Sciences and Technology | And 6 more authors.
Journal of the American College of Cardiology | Year: 2012

Objectives: The purpose of this study was to examine the role of heparanase in controlling thrombosis following vascular injury or endovascular stenting. Background: The use of endovascular stents are a common clinical intervention for the treatment of arteries occluded due to vascular disease. Both heparin and heparan sulfate are known to be potent inhibitors of thrombosis. Heparanase is the major enzyme that degrades heparan sulfate in mammalian cells. This study examined the role of heparanase in controlling thrombosis following vascular injury and stent-induced flow disturbance. Methods: This study used mice overexpressing human heparanase and examined the time to thrombosis using a laser-induced arterial thrombosis model in combination with vascular injury. An ex vivo system was used to examine the formation of thrombus to stent-induced flow disturbance. Results: In the absence of vascular injury, wild type and heparanase overexpressing (HPA Tg) mice had similar times to thrombosis in a laser-induced arterial thrombosis model. However, in the presence of vascular injury, the time to thrombosis was dramatically reduced in HPA Tg mice. An ex vivo system was used to flow blood from wild type and HPA Tg mice over stents and stented arterial segments from both animal types. These studies demonstrate markedly increased thromboses on stents with blood isolated from HPA Tg mice in comparison to blood from wild type animals. We found that blood from HPA Tg animals had markedly increased thrombosis when applied to stented arterial segments from either wild type or HPA Tg mice. Conclusions: Taken together, this study's results indicate that heparanase is a powerful mediator of thrombosis in the context of vascular injury and stent-induced flow disturbance. © 2012 American College of Cardiology Foundation. Source


Sela S.,Hebrew University of Jerusalem | Natanson-Yaron S.,Hadassah University Hospital Mount Scopus | Zcharia E.,Cancer and Vascular Biology Research Center | Vlodavsky I.,Cancer and Vascular Biology Research Center | And 2 more authors.
Circulation Research | Year: 2011

Rationale: The vascular endothelial growth factor (VEGF) decoy receptor soluble VEGF-R1 (sVEGF-R1) is thought to protect the cells that produce it from adverse VEGF signaling. To accomplish this role, a mechanism for pericellular retention of sVEGF-R1 is required. Local retention may also prevent the accumulation of high circulating levels of sVEGF-R1 and resulting interference with homeostatic VEGF functions in remote organs. Objective: To reveal natural storage depots of sVEGF-R1 and determine mechanisms underlying its pericellular retention. To uncover natural mechanisms regulating its systemic release. Methods and Results: We show that both the canonical and human-specific isoforms of sVEGF-R1 are strongly bound to heparin. sVEGF-R1 produced by vascular smooth muscle cells is stored in the vessel wall and can be displaced from isolated mouse aorta by heparin. Another major reservoir of sVEGF-R1 is the placenta. Heparin increases the level of sVEGF-R1 released by cultured human placental villi, and pregnant women treated with low molecular weight heparin showed markedly elevated levels of sVEGF-R1 in the circulation. Heparanase is expressed in human placenta at the same locales as sVEGF-R1, and its transgenic overexpression in mice resulted in a marked increase in the levels of circulating sVEGF-R1. Conversely, heparanase inhibition, by either a neutralizing antibody or by inhibition of its maturation, reduced the amounts of sVEGF-R1 released from human placental villi, indicating a natural role of heparanase in sVEGF-R1 release. Conclusions: Together, the findings uncover a new level of regulation governing sVEGF-R1 retention versus release and suggest that manipulations of the heparin/heparanase system could be harnessed for reducing unwarranted release of sVEGF-R1 in pathologies such as preeclampsia. © 2011 American Heart Association, Inc. Source

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