Neta Ilan

Technion - Israel Institute of Technology, H̱efa, Haifa, Israel

Are you Neta Ilan?

Claim your profile

Publications (131)652.76 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Heparanase is an endo-beta D-glucuronidase capable of cleaving heparan sulfate side chains, yielding heparan sulfate fragments. Heparanase activity has been correlated with the metastatic potential of tumor-derived cells, angiogenesis, autoimmunity and inflammation. We performed a study of heparanase expression in specimens obtained from patients with Langerhans cell histiocytosis (LCH). Paraffin embedded slides from 25 patients were studied by immunohistochemistry for heparanase. Most patients had positive staining for heparanase (21/25). There was no positive association with severity of disease and other clinical characteristics. Further studies are required to clarify the role of heparanase in the pathogenesis of LCH. Pediatr Blood Cancer © 2014 Wiley Periodicals, Inc.
    Pediatric Blood & Cancer 10/2014; 61(10). DOI:10.1002/pbc.25046 · 2.39 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Heparanase has been implicated in cancer but its contribution to the early stages of cancer development is uncertain. In this study, we utilized non-transformed human MCF10A mammary epithelial cells and two genetic mouse models (Hpa-transgenic and knockout mice) to explore heparanase function at early stages of tumor development. Heparanase overexpression resulted in significantly enlarged asymmetrical acinar structures, indicating increased cell proliferation and decreased organization. This phenotype was enhanced by co-expression of heparanase variants with a mutant H-Ras gene, which was sufficient to enable growth of invasive carcinoma in vivo. These observations were extended in vivo by comparing the response of Hpa-transgenic (Hpa-Tg) mice to a classical two-stage DMBA/TPA protocol for skin carcinogenesis. Hpa-Tg mice overexpressing heparanase were far more sensitive than control mice to DMBA/TPA treatment, exhibiting a 10-fold increase in the number and size of tumor lesions. Conversely, DMBA/TPA-induced tumor formation was greatly attenuated in Hpa-KO mice lacking heparanase, pointing to a critical role of heparanase in skin tumorigenesis. In support of these observations, the heparanase inhibitor PG545 potently suppressed tumor progression in this model system. Taken together, our findings establish that heparanase exerts pro-tumorigenic properties at early stages of tumor initiation, co-operating with Ras to dramatically promote malignant development.
    Cancer Research 06/2014; 74(16). DOI:10.1158/0008-5472.CAN-13-2962 · 9.33 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Heparanase is an endo-β-D-glucuronidase that cleaves heparan sulfate chains of proteoglycans, resulting in the disassembly of the extracellular matrix. Heparanase has a central role in the development of various tumors, and its expression has been associated with increased tumor growth, angiogenesis and metastasis, but there is insufficient information about the function of heparanase in sarcomas. Study aims 1) To evaluate heparanase levels in adult soft tissue sarcomas (STS); 2) To examine the correlation between heparanase levels and pathological and clinical parameters and treatment outcome. Pathological specimens of primary or metastatic STS were subjected to immunohistochemical analysis applying an anti-heparanase antibody. The clinical and the pathological data, together with the data of heparanase levels, were evaluated in a logistic regression model for tumor recurrence and survival. One hundred and one samples were examined, 55 from primary tumors and 46 from metastatic sites. A high expression of heparanase was observed in 29 (52.7%) and 22 specimens (47.8%), respectively. There was no statistically significant difference between heparanase expressions in the primary vs. metastatic sites of tumors. Moreover, no correlation was observed between heparanase staining and tumor aggressiveness, tumor recurrence or patient survival in various groups of patients. Expression of heparanase was observed in 50% of the STS, in various histological subtypes. A larger study with homogenous groups of specific sub-types of STS or stages of disease is required to validate over-expression of heparanase as a marker of disease aggressiveness.
    Journal of Experimental & Clinical Cancer Research 05/2014; 33(1):39. DOI:10.1186/1756-9966-33-39 · 4.43 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Heparanase activity plays a decisive role in cell dissemination associated with cancer metastasis. Cellular uptake of heparanase is considered a pre-requisite for the delivery of latent 65-kDa heparanase to lysosomes and its subsequent proteolytic processing and activation into 8- and 50-kDa protein subunits by cathepsin L. Heparan sulfate proteoglycans, and particularly syndecan, are instrumental for heparanase uptake and activation, through a process that has been shown to occur independent of rafts. Nevertheless, the molecular mechanism underlying syndecan-mediated internalization outside of rafts is unclear. Here, we examined the role of syndecan-1 cytoplasmic domain in heparanase processing, utilizing deletion constructs lacking the entire cytoplasmic domain (Delta), the conserved (C1 or C2), or variable (V) regions. Heparanase processing was markedly increased following syndecan-1 over-expression; in contrast, heparanase was retained at the cell membrane and its processing was impaired in cells over-expressing syndecan-1 deleted for the entire cytoplasmic tail. We have next revealed that conserved domain 2 (C2) and variable (V) regions of syndecan-1 cytoplasmic tail mediate heparanase processing. Furthermore, we found that syntenin, known to interact with syndecan C2 domain, and α actinin are essential for heparanase processing.
    Cellular and Molecular Life Sciences CMLS 05/2014; 71(22). DOI:10.1007/s00018-014-1629-9 · 5.81 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: In order to explore the mechanism(s) underlying the pro-tumorigenic capacity of heparanase we established an inducible Tet-on system. Heparanase expression was markedly increased following addition of doxycycline (Dox) to the culture medium of CAG human myeloma cells infected with the inducible heparanase gene construct, resulting in increased colony number and size in soft agar. Moreover, tumor xenografts produced by CAG-heparanase cells were markedly increased in mice supplemented with Dox in their drinking water compared with control mice maintained without Dox. Consistently, we found that heparanase induction is associated with decreased levels of CXCL10, suggesting that this chemokine exerts tumor suppressor properties in myeloma. Indeed, recombinant CXCL10 attenuated the proliferation of CAG, U266 and RPMI-8266 myeloma cells. Similarly, CXCL10 attenuated the proliferation of human umbilical vein endothelial cells (HUVEC), implying that CXCL10 exhibits anti-angiogenic capacity. Strikingly, development of tumor xenografts produced by CAG-heparanase cells over expressing CXCL10 was markedly reduced compared with control cells. Moreover, tumor growth was significantly attenuated in mice inoculated with human or mouse myeloma cells and treated with CXCL10-Ig fusion protein, indicating that CXCL10 functions as a potent anti-myeloma cytokine.Leukemia accepted article preview online, 04 April 2014; doi:10.1038/leu.2014.121.
    Leukemia: official journal of the Leukemia Society of America, Leukemia Research Fund, U.K 04/2014; 28(11). DOI:10.1038/leu.2014.121 · 10.43 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Heparanase has generated substantial interest as therapeutic target for antitumor therapy, because its activity is implicated in malignant behavior of cancer cells and in tumor progression. Increased heparanase expression was found in numerous tumor types and correlates with poor prognosis. Heparanase, an endoglucuronidase responsible for heparan sulfate cleavage, regulates the structure and function of heparan sulfate proteoglycans, leading to disassembly of the extracellular matrix. The action of heparanase is involved in multiple regulatory events related, among other effects, to augmented bioavailability of growth factors and cytokines. Inhibitors of heparanase suppress tumor growth, angiogenesis and metastasis by modulating growth factor-mediated signaling, ECM barrier function and cell interactions in the tumor microenvironment. Therefore, targeting heparanase has potential implications for anti-tumor, anti-angiogenic and anti-inflammatory therapies. Current approaches for heparanase inhibition include development of chemically-modified heparins, small molecule inhibitors and neutralizing antibodies. The available evidence supports the emerging utility of heparanase inhibition as a promising antitumor strategy, specifically in rational combination with other agents. The recent studies with compounds designed to block heparanase (e.g., modified heparins) provide a rational basis for their therapeutic application and optimization.
    Biochemical pharmacology 02/2014; 89(1). DOI:10.1016/j.bcp.2014.02.010 · 5.01 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: In an attempt to isolate a heparanase receptor, postulated to mediate non-enzymatic functions of the heparanase protein, we utilized human urine collected from healthy volunteers. Affinity chromatography of this rich protein source on immobilized heparanase revealed resistin as a heparanase binding protein. Co-immunoprecipitation and ELISA further confirmed the interaction between heparanase and resistin. Importantly, we found that heparanase potentiates the bioactivity of resistin in its standard bioassay in which monocytic human leukemia cell line, THP1, differentiates into adherent macrophage-like foam cells. It is thus conceivable that this newly identified complex of heparanase and resistin exerts a stimulatory effect also in various inflammatory conditions known to be affected by the two proteins.
    PLoS ONE 01/2014; 9(1):e85944. DOI:10.1371/journal.pone.0085944 · 3.23 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Heparanase is an endo-β-glucuronidase that specifically cleaves the saccharide chains of HSPGs, important structural and functional components of the ECM. Cleavage of HS leads to loss of the structural integrity of the ECM and release of HS-bound cytokines, chemokines, and bioactive angiogenic- and growth-promoting factors. Our previous study revealed a highly significant correlation of HPSE gene SNPs rs4693608 and rs4364254 and their combination with the risk of developing GVHD. We now demonstrate that HPSE is up-regulated in response to pretransplantation conditioning, followed by a gradual decrease thereafter. Expression of heparanase correlated with the rs4693608 HPSE SNP before and after conditioning. Moreover, a positive correlation was found between recipient and donor rs4693608 SNP discrepancy and the time of neutrophil and platelet recovery. Similarly, the discrepancy in rs4693608 HPSE SNP between recipients and donors was found to be a more significant factor for the risk of aGVHD than patient genotype. The rs4693608 SNP also affected HPSE gene expression in LPS-treated MNCs from PB and CB. Possessors of the AA genotype exhibited up-regulation of heparanase with a high ratio in the LPS-treated MNCs, whereas individuals with genotype GG showed down-regulation or no effect on HPSE gene expression. HPSE up-regulation was mediated by TLR4. The study emphasizes the importance of rs4693608 SNP for HPSE gene expression in activated MNCs, indicating a role in allogeneic stem cell transplantation, including postconditioning, engraftment, and GVHD.
    Journal of leukocyte biology 12/2013; 95(4). DOI:10.1189/jlb.0313147 · 4.29 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Heparanase functions as a heparan sulphate-degrading enzyme and as a ligand for an unidentified signalling receptor(s). Here, several reactions involved in the activation of the PI3K-AKT pathway by latent heparanase were characterised. Protein suppression using specific siRNAs revealed that heparanase-induced phosphorylation of AKT at Ser473 was RICTOR-mTOR-dependent, while ILK and PAK1/2 were dispensable. p110α was the PI3K catalytic isoform preferred by heparanase for AKT activation and cell proliferation, as the p110α inhibitor YM024 blocked these processes. Heparanase-induced AKT phosphorylation was low in MEF cells expressing a RAS interaction-defective p110α compared to wild type cells, indicating that RAS has an important role in the PI3K-AKT activation. The response to heparanase was also inefficient in suspension cultures of several cell lines, suggesting a requirement of integrins in this pathway. Adhesion via either αVβ3 or α5β1 promoted heparanase-induced AKT phosphorylation, and a stronger effect was seen when both integrins were engaged. Simultaneous inhibition of FAK and PYK2 using a chemical inhibitor, or suppression of their expression, inhibited heparanase-induced AKT activation and cell proliferation. Stimulation of cells with heparanase enhanced their resistance against oxidative stress- or growth factor starvation-induced apoptosis. These results demonstrate that there is an intimate crosstalk between the heparanase receptor(s) and integrins during induction of the pro-survival PI3K-AKT pathway by heparanase.
    Journal of Biological Chemistry 03/2013; 288(17). DOI:10.1074/jbc.M112.435172 · 4.57 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Heparanase, the sole mammalian endoglycosidase degrading heparan sulfate, is causally involved in cancer metastasis, angiogenesis, inflammation and kidney dysfunction. Despite the wide occurrence and impact of heparan sulfate proteoglycans in vascular biology, the significance of heparanase in vessel wall disorders is underestimated. Blood vessels are highly active structures whose morphology rapidly adapts to maintain vascular function under altered systemic and local conditions. In some pathologies (restenosis, thrombosis, atherosclerosis) this normally beneficial adaptation may be detrimental to overall function. Enzymatic dependent and independent effects of heparanase on arterial structure mechanics and repair closely regulate arterial compliance and neointimal proliferation following endovascular stenting. Additionally, heparanase promotes thrombosis after vascular injury and contributes to a pro-coagulant state in human carotid atherosclerosis. Importantly, heparanase is closely associated with development and progression of atherosclerotic plaques, including stable to unstable plaque transition. Consequently, heparanase levels are markedly increased in the plasma of patients with acute myocardial infarction. Noteworthy, heparanase activates macrophages, resulting in marked induction of cytokine expression associated with plaque progression towards vulnerability. Together, heparanase emerges as a regulator of vulnerable lesion development and potential target for therapeutic intervention in atherosclerosis and related vessel wall complications.
    Matrix biology: journal of the International Society for Matrix Biology 03/2013; 32(5). DOI:10.1016/j.matbio.2013.03.002 · 5.07 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: T5 is a novel splice variant of heparanase, an endo-β-D-glucuronidase capable of cleaving heparan sulfate side chains at a limited number of sites. T5 splice variant is endowed with pro-tumorigenic properties, enhancing cell proliferation, anchorage independent growth and tumor xenograft development despite lack of heparan sulfate-degrading activity typical of heparanase. T5 is over expressed in the majority of human renal cell carcinoma biopsies examined, suggesting that this splice variant is clinically relevant. T5 is thought to assume a distinct three-dimensional conformation compared with the wild type heparanase protein. We sought to exploit this presumed feature by generating monoclonal antibodies that will recognize the unique structure of T5 without, or with minimal recognition of heparanase, thus enabling more accurate assessment of the clinical relevance of T5. We provide evidence that such a monoclonal antibody, 9c9, preferentially recognizes T5 compared with heparanase by ELISA, immunoblotting and immunohistochemistry. In order to uncover the clinical significance of T5, a cohort of renal cell carcinoma specimens was subjected to immunostaining applying the 9c9 antibody. Notably, T5 staining intensity was significantly associated with tumor size (p = 0.004) and tumor grade (p = 0.02). Our results suggest that T5 is a functional, pro-tumorigenic entity.
    PLoS ONE 12/2012; 7(12):e51494. DOI:10.1371/journal.pone.0051494 · 3.23 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Objective: Factors and mechanisms that activate macrophages in atherosclerotic plaques are incompletely understood. We examined the capacity of heparanase to activate macrophages. Methods and results: Highly purified heparanase was added to mouse peritoneal macrophages and macrophage-like J774 cells, and the levels of tumor necrosis factor-α, matrix metalloproteinase-9, interlukin-1, and monocyte chemotactic protein-1 were evaluated by ELISA. Gene expression was determined by RT-PCR. Cells collected from Toll-like receptor-2 and Toll-like receptor-4 knockout mice were evaluated similarly. Heparanase levels in the plasma of patients with acute myocardial infarction, stable angina, and healthy subjects were determined by ELISA. Immunohistochemistry was applied to detect the expression of heparanase in control specimens and specimens of patients with stable angina or acute myocardial infarction. Addition or overexpression of heparanase variants resulted in marked increase in tumor necrosis factor-α, matrix metalloproteinase-9, interlukin-1, and monocyte chemotactic protein-1 levels. Mouse peritoneal macrophages harvested from Toll-like receptor-2 or Toll-like receptor-4 knockout mice were not activated by heparanase. Plasma heparanase level was higher in patients with acute myocardial infarction, compared with patients with stable angina and healthy subjects. Pathologic coronary specimens obtained from vulnerable plaques showed increased heparanase staining compared with specimens of stable plaque and controls. Conclusions: Heparanase activates macrophages, resulting in marked induction of cytokine expression associated with plaque progression toward vulnerability.
    Arteriosclerosis Thrombosis and Vascular Biology 11/2012; 33(2). DOI:10.1161/ATVBAHA.112.254961 · 6.00 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Heparanase is an endo-β-glucuronidase that cleaves heparan sulfate side chains, leading to structural modifications that loosen the extracellular matrix barrier and associated with tumor metastasis, inflammation and angiogenesis. In addition, the highly sulfated heparan sulfate proteoglycans are important constituents of the glomerular basement membrane and its permselective properties. Recent studies suggest a role for heparanase in several experimental and human glomerular diseases associated with proteinuria such as diabetes, minimal change disease, and membranous nephropathy. Here, we quantified blood and urine heparanase levels in renal transplant recipients and patients with chronic kidney disease (CKD), and assessed whether alterations in heparanase levels correlate with proteinuria and renal function. We report that in transplanted patients, urinary heparanase was markedly elevated, inversely associated with estimated glomerular filtration rate (eGFR), suggesting a relationship between heparanase and graft function. In CKD patients, urinary heparanase was markedly elevated and associated with proteinuria, but not with eGFR. In addition, urinary heparanase correlated significantly with plasma heparanase in transplanted patients. Such a systemic spread of heparanase may lead to damage of cells and tissues alongside the kidney.The newly described association between heparanase, proteinuria and decreased renal function is expected to pave the way for new therapeutic options aimed at attenuating chronic renal allograft nephropathy, leading to improved graft survival and patient outcome.
    PLoS ONE 09/2012; 7(9):e44076. DOI:10.1371/journal.pone.0044076 · 3.23 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Activity of heparanase is implicated strongly in dissemination of metastatic tumor cells and cells of the immune system. In addition, heparanase enhances the phosphorylation of selected signaling molecules, including SRC and EGFR, in a manner that requires secretion but not enzymatic activity of heparanase and is mediated by its C-terminal domain. Clinically, heparanase staining is associated with larger tumors and increased EGFR phosphorylation in head and neck carcinoma. We hypothesized that signal transducer and activator of transcription (STAT) proteins mediate the protumorigenic function of heparanase downstream of the EGFR. We provide evidence that heparanase enhances the phosphorylation of STAT3 and STAT5b but not STAT5a. Moreover, enhanced proliferation of heparanase transfected cells was attenuated by STAT3 and STAT5b siRNA, but not STAT5a or STAT1 siRNA. Clinically, STAT3 phosphorylation was associated with head and neck cancer progression, EGFR phosphorylation, and heparanase expression and cellular localization. Notably, cytoplasmic rather than nuclear phospho-STAT3 correlated with increased tumor size (T-stage; p = 0.007), number of metastatic neck lymph nodes (p = 0.05), and reduced survival of patients (p = 0.04).
    Journal of Biological Chemistry 12/2011; 287(9):6668-78. DOI:10.1074/jbc.M111.271346 · 4.57 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Pituitary tumorigenesis involves remodeling of the extracellular matrix (ECM). Heparanase, an endoglycosidase capable of degrading heparan sulfate, a major polysaccharide constituent of the ECM, is implicated in diverse processes associated with ECM remodeling, such as morphogenesis, angiogenesis, and tumor invasion. The aim of this study was to investigate the possible role of heparanase in pituitary tumorigenesis. Human normal pituitaries and pituitary tumors were examined for heparanase mRNA and protein expression using real-time PCR and immunohistochemistry, respectively. Cell proliferation was assessed by colony formation after heparanase overexpression in GH3 and MtT/S cells. Cell viability and cell cycle progression were evaluated after heparanase gene silencing. Higher heparanase mRNA and protein expression was noted in GH tumors as compared with normal pituitaries. Heparanase overexpression in GH3 and MtT/S cells resulted in a 2- to 3-fold increase in colony number, compared with control cells. Cell viability decreased by 50% after heparanase gene silencing due to induced apoptosis reflected by increased fraction of cleaved poly-ADP-ribose polymerase and sub-G1 events. Notably, exogenously added heparanase enhanced epidermal growth factor receptor, Src, Akt, ERK, and p38 phosphorylation in pituitary tumor cells. Our results indicate that heparanase enhances pituitary cell viability and proliferation and may thus contribute to pituitary tumor development and progression.
    Endocrinology 12/2011; 152(12):4562-70. DOI:10.1210/en.2011-0273 · 4.50 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Heparan sulfate proteoglycans (HSPGs) are primary components at the interface between virtually every eukaryotic cell and its extracellular matrix. HSPGs not only provide a storage depot for heparin-binding molecules in the cell microenvironment, but also decisively regulate their accessibility, function and mode of action. As such, they are intimately involved in modulating cell invasion and signaling loops that are critical for tumor growth, inflammation and kidney function. In a series of studies performed since the cloning of the human heparanase gene, we and others have demonstrated that heparanase, the sole heparan sulfate degrading endoglycosidase, is causally involved in cancer progression, inflammation and diabetic nephropathy and hence is a valid target for drug development. Heparanase is causally involved in inflammation and accelerates colon tumorigenesis associated with inflammatory bowel disease. Notably, heparanase stimulates macrophage activation, while macrophages induce production and activation of latent heparanase contributed by the colon epithelium, together generating a vicious cycle that powers colitis and the associated tumorigenesis. Heparanase also plays a decisive role in the pathogenesis of diabetic nephropathy, degrading heparan sulfate in the glomerular basement membrane and ultimately leading to proteinuria and kidney dysfunction. Notably, clinically relevant doses of ionizing radiation (IR) upregulate heparanase expression and thereby augment the metastatic potential of pancreatic carcinoma. Thus, combining radiotherapy with heparanase inhibition is an effective strategy to prevent tumor resistance and dissemination in IR-treated pancreatic cancer patients. Also, accumulating evidence indicate that peptides derived from human heparanase elicit a potent anti-tumor immune response, suggesting that heparanase represents a promising target antigen for immunotherapeutic approaches against a broad variety of tumours. Oligosaccharide-based compounds that inhibit heparanase enzymatic activity were developed, aiming primarily at halting tumor growth, metastasis and angiogenesis. Some of these compounds are being evaluated in clinical trials, targeting both the tumor and tumor microenvironment.
    Cancer Microenvironment 08/2011; 5(2):115-32. DOI:10.1007/s12307-011-0082-7
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Metastases formation depends on the ability of tumor cells to invade basement membranes in a process involving enzymes capable of degrading extracellular matrix components. We examined the expression of heparanase in oral carcinomas and correlated its staining extent, intensity, and cellular localization with patients' outcome. Quantitative real-time polymerase chain reaction (PCR) revealed over 4-fold increase in heparanase levels in oral carcinomas compared to adjacent normal tissue. Normal oral epithelium was found negative for heparanase, while all oral carcinomas stained positively for heparanase. Heparanase staining was associated with Ki67 staining, a measure of cell proliferation. Notably, whereas cytoplasmic localization of heparanase was associated with high-grade carcinomas, nuclear localization of the enzyme was found primarily in low-grade, well-differentiated tumors, and in all oral verrucous carcinomas. Expression level and cellular localization of heparanase could serve as an important diagnostic marker in patients with oral cancer.
    Head & Neck 06/2011; 33(6):871-7. DOI:10.1002/hed.21545 · 2.64 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Heparanase is an endoglycosidase that specifically cleaves heparan sulfate side chains of heparan sulfate proteoglycans. Utilizing an ELISA method capable of detection and quantification of heparanase, we examined heparanase levels in the plasma and urine of a cohort of 29 patients diagnosed with type 2 diabetes mellitus (T2DM), 14 T2DM patients who underwent kidney transplantation, and 47 healthy volunteers. We provide evidence that heparanase levels in the urine of T2DM patients are markedly elevated compared to healthy controls (1162 ± 181 vs. 156 ± 29.6 pg/ml for T2DM and healthy controls, respectively), increase that is statistically highly significant (P<0.0001). Notably, heparanase levels were appreciably decreased in the urine of T2DM patients who underwent kidney transplantation, albeit remained still higher than healthy individuals (P<0.0001). Increased heparanase levels were also found in the plasma of T2DM patients. Importantly, urine heparanase was associated with elevated blood glucose levels, implying that glucose mediates heparanase upregulation and secretion into the urine and blood. Utilizing an in vitro system, we show that insulin stimulates heparanase secretion by kidney 293 cells, and even higher secretion is observed when insulin is added to cells maintained under high glucose conditions. These results provide evidence for a significant involvement of heparanase in diabetic complications.
    PLoS ONE 02/2011; 6(2):e17312. DOI:10.1371/journal.pone.0017312 · 3.23 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Tumor metastasis, the leading cause of cancer patients' death, is still insufficiently understood. While concepts and mechanisms of tumor metastasis are evolving, it is widely accepted that cancer metastasis is accompanied by orchestrated proteolytic activity executed by array of proteases. While matrix metalloproteinases (MMPs) attracted much attention, other proteases constitute the tumor milieu, of which a large family consists of cysteine proteases named cathepsins. Like MMPs, some cathepsins are often upregulated in cancer and, once secreted or localized to the cell surface, can degrade components of the extracellular matrix. In addition, cathepsin L is held responsible for processing and activation of heparanase, an endo-β-glucuronidase capable of cleaving heparan sulfate side chains of heparan sulfate proteoglycans, activity that is strongly implicated in cell dissemination associated with tumor metastasis, angiogenesis, and inflammation. In this review, we discuss recent progress in heparanase research focusing on heparanase-related molecules namely, cathepsin L and heparanase 2 (Hpa2), a heparanase homolog.
    CANCER AND METASTASIS REVIEW 02/2011; 30(2):253-68. DOI:10.1007/s10555-011-9288-x · 7.23 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Heparanase is an endo-β-D-glucuronidase that cleaves heparan sulfate (HS) side chains at a limited number of sites, activity that is strongly implicated with cell invasion associated with cancer metastasis, a consequence of structural modification that loosens the extracellular matrix barrier. Heparanase activity is also implicated in neovascularization, inflammation, and autoimmunity, involving migration of vascular endothelial cells and activated cells of the immune system. The cloning of a single human heparanase cDNA 10 years ago enabled researchers to critically approve the notion that HS cleavage by heparanase is required for structural remodeling of the extracellular matrix (ECM), thereby facilitating cell invasion. Heparanase is preferentially expressed in human tumors and its over-expression in tumor cells confers an invasive phenotype in experimental animals. The enzyme also releases angiogenic factors residing in the tumor microenvironment and thereby induces an angiogenic response in vivo. Heparanase up-regulation correlates with increased tumor vascularity and poor postoperative survival of cancer patients. These observations, the anticancerous effect of heparanase gene silencing and of heparanase-inhibiting molecules, as well as the unexpected identification of a single functional heparanase suggest that the enzyme is a promising target for anticancer drug development. Progress in the field expanded the scope of heparanase function and its significance in tumor progression and other pathologies such as inflammatory bowel disease and diabetic nephropathy. Notably, while heparanase inhibitors attenuated tumor progression and metastasis in several experimental systems, other studies revealed that heparanase also functions in an enzymatic activity-independent manner. Thus, point-mutated inactive heparanase was noted to promote phosphorylation of signaling molecules such as Akt and Src, facilitating gene transcription (i.e. VEGF) and phosphorylation of selected Src substrates (i.e. EGF receptor). The concept of enzymatic activity-independent function of heparanase gained substantial support by elucidation of the heparanase C-terminus domain as the molecular determinant behind its signaling capacity and the identification of a human heparanase splice variant (T5) devoid of enzymatic activity, yet endowed with protumorigenic characteristics. Resolving the heparanase crystal structure will accelerate rational design of effective inhibitory molecules and neutralizing antibodies, paving the way for advanced clinical trials in patients with cancer and other diseases involving heparanase.
    01/2011; 2(1):e0019. DOI:10.5041/RMMJ.10019

Publication Stats

5k Citations
652.76 Total Impact Points


  • 2006–2014
    • Technion - Israel Institute of Technology
      • Ruth and Bruce Rappaport Faculty of Medicine
      H̱efa, Haifa, Israel
  • 2010
    • University of North Carolina at Chapel Hill
      • Department of Medicine
      North Carolina, United States
  • 2002–2009
    • Tel Aviv University
      • • Faculty of Life Sciences
      • • Department of Molecular Biology and Ecology of Plants
      • • Department of Physiology and Pharmacology
      Tell Afif, Tel Aviv, Israel
  • 1988–2008
    • Hebrew University of Jerusalem
      • • Department of Oncology
      • • Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture
      Yerushalayim, Jerusalem, Israel
  • 2007
    • Carmel Medical Center
      H̱efa, Haifa District, Israel
  • 2005
    • InSight Biopharmaceuticals Ltd.
      Tell Afif, Tel Aviv, Israel
  • 1998–2001
    • Yale-New Haven Hospital
      • Department of Pathology
      New Haven, Connecticut, United States
  • 2000
    • Yale University
      New Haven, Connecticut, United States
  • 1996
    • Agricultural Research Organization ARO
      • Institute of Animal Science
      Beit Dajan, Central District, Israel