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World Journal of Gastroenterology Aug 2014To demonstrate that administering heparanase inhibitor PI-88 at 160 mg/d is safe and promising in reducing hepatocellular carcinoma (HCC) recurrence for up to 3 year... (Observational Study)
Observational Study Randomized Controlled Trial
AIM
To demonstrate that administering heparanase inhibitor PI-88 at 160 mg/d is safe and promising in reducing hepatocellular carcinoma (HCC) recurrence for up to 3 year following curative resection.
METHODS
A total of 143 patients (83.1% of the 172 participants in the phase II study) participated in the follow-up study. Of these patients, 50 had received no treatment, 48 had received 160 mg/d PI-88, and 45 had received 250 mg/d PI-88 during the phase II trial. Safety parameters and the following efficacy endpoints were investigated: (1) time to recurrence; (2) disease-free survival; and (3) overall survival.
RESULTS
PI-88 at 160 mg/d delayed the onset and frequency of HCC recurrence, and provided a clinically significant survival advantage for up to 3 years after treatment compared with those of the control group: (1) the recurrence-free rate increased from 50% to 63%, and (2) time to recurrence at the 36th percentile was postponed by 78%. The efficacy of administering PI-88 at 250 mg/d was confounded by a high dropout rate (11 out of 54 patients). Additionally, subgroup analyses of patients with (1) multiple tumors or a single tumor ≥ 2 cm; and (2) hepatitis B or C revealed that administering PI-88 at 160 mg/d conferred the most significant survival advantage (56.8% improvement in disease-free survival, P = 0.045) for patients with both risk factors for recurrence.
CONCLUSION
Administering PI-88 at 160 mg/d is a safe and well-tolerated dosage that may confer significant clinical benefits for patients with HCC.
Topics: Adult; Aged; Antineoplastic Agents; Carcinoma, Hepatocellular; Chemotherapy, Adjuvant; Disease-Free Survival; Drug Administration Schedule; Enzyme Inhibitors; Female; Glucuronidase; Humans; Liver Neoplasms; Male; Middle Aged; Oligosaccharides; Risk Factors; Survival Analysis; Taiwan; Time Factors; Treatment Outcome
PubMed: 25170226
DOI: 10.3748/wjg.v20.i32.11384 -
Matrix Biology : Journal of the... Jun 2013Heparanase (Hpse) is an endo-β-d-glucuronidase that degrades the glycosaminoglycan heparan sulfate (HS) in basement membranes (BMs) to facilitate leukocyte migration... (Review)
Review
Heparanase (Hpse) is an endo-β-d-glucuronidase that degrades the glycosaminoglycan heparan sulfate (HS) in basement membranes (BMs) to facilitate leukocyte migration into tissues. Heparanase activity also releases HS-bound growth factors from the extracellular matrix (ECM), a function that aids wound healing and angiogenesis. In disease states, the degradation of HS in BMs by heparanase is well recognized as an invasive property of metastatic cancer cells. Recent studies by our group, however, have identified unexpected new roles for heparanase and HS. First, we discovered that in Type 1 diabetes (T1D) (i) HS in the pancreatic islet BM acts as a barrier to invading cells and (ii) high levels of HS within the insulin-producing islet beta cells themselves are critical for beta cell survival, protecting the cells from free radical-mediated damage. Furthermore, catalytically active heparanase produced by autoreactive T cells and other insulitis mononuclear cells was shown to degrade intra-islet HS, increasing the susceptibility of islet beta cells to free radical damage and death. This totally novel molecular explanation for the onset of T1D diabetes opens up new therapeutic approaches for preventing disease progression. Indeed, administration of the heparanase inhibitor, PI-88, dramatically reduced T1D incidence in diabetes-prone NOD mice, preserved islet beta cell HS and reduced islet inflammation. Second, in parallel studies it has been shown that heparanase and HS can be transported to the nucleus of cells where they impact directly or indirectly on gene transcription. Based on ChIP-on-chip studies heparanase was found to interact with the promoters and transcribed regions of several hundred genes and micro-RNAs in activated Jurkat T cells and up-regulate transcription, with many of the target genes/micro-RNAs being involved in T cell differentiation. At the molecular level, nuclear heparanase appears to regulate histone 3 lysine 4 (H3K4) methylation by influencing the recruitment of demethylases to transcriptionally active genes. These studies have unveiled new functions for heparanase produced by T lymphocytes, with the enzyme mediating unexpected intracellular effects on T cell differentiation and insulin-producing beta cell survival in T cell-dependent autoimmune T1D.
Topics: Animals; Cell Proliferation; Diabetes Mellitus, Type 1; Enzyme Inhibitors; Extracellular Matrix; Free Radicals; Gene Expression Regulation; Glucuronidase; Heparitin Sulfate; Humans; Islets of Langerhans; Mice; Oligosaccharides; Signal Transduction; T-Lymphocytes
PubMed: 23499527
DOI: 10.1016/j.matbio.2013.02.007 -
Investigative Ophthalmology & Visual... Oct 2012Heparanase and VEGF are related closely to angiogenesis in cancer. The purpose of our study was to evaluate the expression and correlation of heparanase and VEGF in... (Comparative Study)
Comparative Study
PURPOSE
Heparanase and VEGF are related closely to angiogenesis in cancer. The purpose of our study was to evaluate the expression and correlation of heparanase and VEGF in hypoxia-induced retinal neovascularization.
METHODS
C57BL/6 oxygen-induced retinopathy (OIR) mice and human retinal microvascular endothelial cells (HRECs) were treated with the hypoxia mimetic agent cobalt chloride (CoCl₂), and in the presence of the heparanase inhibitor phosphomannopentaose sulfate (Muparfostat, PI-88). Heparanase activity was assayed in HRECs, and the expression of heparanase, VEGF protein and mRNA were evaluated by immunofluorescence, ELISA, Western blot, and real-time PCR while retinal flat mounts were used to evaluate the area of neovascularization of mice retina.
RESULTS
HREC heparanase activity was increased by treatment with CoCl₂, but was decreased by PI-88. Immunofluorescence showed that heparanase and VEGF staining was intense in hypoxia-treated HRECs and OIR mice retina, while VEGF staining was faint in the normoxia and PI-88-treated ones. Western blot and real-time PCR results indicated that the expression of heparanase and VEGF was increased under hypoxic conditions, and the increase of VEGF was inhibited by PI-88. Retinal flat mounts showed that the area of new vessels in retina of OIR mice was increased compared to the normoxic mice, and this effect was inhibited by PI-88.
CONCLUSIONS
Heparanase is upregulated and associated with the VEGF expression in hypoxia-induced retinal diseases. Heparanase is involved in hypoxia-induced neovascularization through promoting VEGF expression and may be a new therapeutic target for hypoxia-induced neovascularization retinal diseases.
Topics: Animals; Animals, Newborn; Blotting, Western; Disease Models, Animal; Enzyme-Linked Immunosorbent Assay; Female; Gene Expression Regulation; Glucuronidase; Humans; Hypoxia; Male; Mice; Mice, Inbred C57BL; RNA; Real-Time Polymerase Chain Reaction; Retina; Retinal Neovascularization; Vascular Endothelial Growth Factor A
PubMed: 22956610
DOI: 10.1167/iovs.11-9144 -
Molecular Vision 2012Vascular endothelial growth factor (VEGF) is the most potent angiogenic mitogen, and has been associated with angiogenesis. Heparanase is an endoglycosidase that...
Phosphomannopentaose sulfate (PI-88) suppresses angiogenesis by downregulating heparanase and vascular endothelial growth factor in an oxygen-induced retinal neovascularization animal model.
PURPOSE
Vascular endothelial growth factor (VEGF) is the most potent angiogenic mitogen, and has been associated with angiogenesis. Heparanase is an endoglycosidase that specifically cleaves heparan sulfate side chains, which can induce VEGF expression. The aims of the present study were to evaluate the heparanase expression and its relationship with VEGF in the retina of oxygen-induced retinopathy (OIR) mice, and to investigate the effect of the heparanase inhibitor phosphomannopentaose sulfate (PI-88) in the OIR retinas.
METHODS
Seventy-seven newborn C57BL/6 mice were involved in this study. On postnatal day 7 (P7), pups were exposed to a hyperoxia condition (75% oxygen) for 5 days, and on P12, the mice were returned to room air. Control mice were exposed to room air from birth until P17, with normally developing retinal vasculature. PI-88 was administered intraperitoneally to OIR mice at a dose of 35.7 mg/kg/day for 5 consecutive days. The expression level of heparanase and VEGF in the retinas was assayed using immunohistochemistry, Q-RT-PCR, and western blot.
RESULTS
The expression levels of heparanase and VEGF were increased in the OIR retinas compared with the control mice. The Q-RT-PCR results showed that the mRNA expression levels of heparanase and VEGF in OIR retina were increased 1.71 fold (p<0.0001) and 4.34 fold (p<0.0001), respectively. The western blot results showed that the protein expression levels of heparanase and VEGF were increased 1.49 fold (p<0.0001) and 1.72 fold (p<0.0001), respectively, in the OIR retinas compared with the normal retinas. The immunohistochemistry analysis revealed that the heparanase and VEGF signals were intense in the retinal vascular endothelia of the OIR mice but faint in those of the normal controls. The increased protein and mRNA expression levels of heparanase and VEGF in the mouse retinas were significantly decreased by PI-88 administration (p<0.0001).
CONCLUSIONS
Heparanase expression was upregulated and correlated with an increase in VEGF expression in the OIR mouse retinas, and might be involved in the progress of retinopathy of prematurity. Inhibition of heparanase expression by PI-88 could be used as a novel therapeutic method for retinopathy of prematurity.
Topics: Animals; Animals, Newborn; Disease Models, Animal; Down-Regulation; Glucuronidase; Humans; Infant, Newborn; Injections, Intraperitoneal; Mice; Mice, Inbred C57BL; Oligosaccharides; Oxygen; Retinal Neovascularization; Retinopathy of Prematurity; Vascular Endothelial Growth Factor A
PubMed: 22773903
DOI: No ID Found -
Bioorganic & Medicinal Chemistry Letters Jul 2012Tumor-associated angiogenesis is a complex process that involves the interplay among several molecular players such as cell-surface heparan sulfate proteoglycans,...
Tumor-associated angiogenesis is a complex process that involves the interplay among several molecular players such as cell-surface heparan sulfate proteoglycans, vascular endothelial growth factors and their cognate receptors. PI-88, a highly sulfonated oligosaccharide, has been shown to have potent anti-angiogenic activity and is currently in clinical trials. However, one of the major drawbacks of large oligosaccharides such as PI-88 is that their synthesis often requires numerous complex synthetic steps. In this study, several novel polysulfonated small molecule carbohydrate mimetics, which can easily be synthesized in fewer steps, are identified as promising inhibitors of angiogenesis in an in vitro tube formation assay.
Topics: Angiogenesis Inhibitors; Animals; Biomimetic Materials; Cattle; Drug Evaluation, Preclinical; Endothelial Cells; Microtubules; Oligosaccharides; Small Molecule Libraries; Sulfur
PubMed: 22627041
DOI: 10.1016/j.bmcl.2012.04.014 -
Matrix Biology : Journal of the... Jun 2012Heparin and its derivatives are known to regulate a variety of pathophysiological events related to vascular biology. In the present manuscript we examine a variety of...
Heparin and its derivatives are known to regulate a variety of pathophysiological events related to vascular biology. In the present manuscript we examine a variety of heparinomimetics biochemically (electrophoretic behavior and enzymatic degradation) and pharmacologically (in vitro anticoagulant activity and in vivo hemorrhagic and antithrombotic tests) as well as their interactions with cells from the vessel wall using a time resolved fluorometric method and confocal microscopy. Data were determined for unfractionated heparin (UFH), enoxaparin, synthetic heparin pentasaccharide, C3 heparin derived oligosaccharides and phosphosulfomannan (PI-88). While being structurally distinct from UFH, all compounds exhibited anticoagulant, antithrombotic and hemorrhagic activities. In addition, besides the pentasaccharide, they all stimulated the synthesis of an antithrombotic heparan sulfate present at the cell surface and secreted by endothelial cells. Also, like UFH, they interacted with both endothelial and smooth muscle cells and dislodged UFH from its binding sites in a dose dependent manner but, with distinct saturable curves showing that the binding of polymeric structures to extracellular matrix (ECM) proteins does not depend on a glycosaminoglycan backbone. The data also suggest a common pathway, which does not depend on the presence of the conventionally accepted antithrombin binding pentasaccharide, for ECM dependent activity of the heparinomimetic stimulated synthesis of antithrombotic heparan sulfate. Notably, although of similar molecular weight as well as polymeric backbone, the synthetic heparin pentasaccharide showed significant hemorrhagic action and negligible antithrombotic activity in a venous thrombosis model, contrasting with C3, that displayed negligible hemorrhagic effect and potent antithrombotic action. These results provide evidence that structurally unrelated polymers can elicit similar hemostatic activities and show that polymeric sequence is not always crucial for certain activities. The results also suggest that non-GAG structures may provide an alternative route for the pharmaceutical control of hemostasis.
Topics: Animals; Anticoagulants; Binding Sites; Dose-Response Relationship, Drug; Endothelial Cells; Extracellular Matrix; Fibrinolytic Agents; Hemostasis; Heparin; Heparin Lyase; Molecular Weight; Myocytes, Smooth Muscle; Oligosaccharides; Protein Binding; Proteolysis; Rabbits; Rats; Substrate Specificity
PubMed: 22504459
DOI: 10.1016/j.matbio.2012.03.001 -
Neoplasia (New York, N.Y.) Nov 2010Heparanase-1 (HPR1), an endoglycosidase that specifically degrades heparan sulfate (HS) proteoglycans, is overexpressed in a variety of malignancies. Our present study...
Heparanase-1 (HPR1), an endoglycosidase that specifically degrades heparan sulfate (HS) proteoglycans, is overexpressed in a variety of malignancies. Our present study sought to determine whether oncogene BRAF and RAS mutations lead to increased HPR1 expression. Reverse transcription-polymerase chain reaction analysis revealed that HPR1 gene expression was increased in HEK293 cells transiently transfected with a mutant BRAF or RAS gene. Flow cytometric analysis revealed that B-Raf activation led to loss of the cell surface HS, which could be blocked by two HPR1 inhibitors: heparin and PI-88. Cotransfection of a BRAF or RAS mutant gene with HPR1 promoter-driven luciferase reporters increased luciferase reporter gene expression in HEK293 cells. Knockdown of BRAF expression in a BRAF-mutated KAT-10 tumor cell line led to the suppression of HPR1 gene expression, subsequently leading to increased cell surface HS levels. Truncational and mutational analyses of the HPR1 promoter revealed that the Ets-relevant elements in the HPR1 promoter were critical for BRAF activation-induced HPR1 expression. Luciferase reporter gene expression driven by a four-copy GA binding protein (GABP) binding site was significantly lower in BRAF siRNA-transfected KAT-10 cells than in the control siRNA-transfected cells. We further showed that BRAF knockdown led to suppression of the expression of the GABPβ, an Ets family transcription factor involved in regulating HPR1 promoter activity. Taken together, our study suggests that B-Raf kinase activation plays an important role in regulating HPR1 expression. Increased HPR1 expression may contribute to the aggressive behavior of BRAF-mutated cancer.
Topics: Binding Sites; Blotting, Western; Cell Line, Tumor; Enzyme Activation; GA-Binding Protein Transcription Factor; Gene Expression Regulation, Enzymologic; Glucuronidase; HEK293 Cells; Heparin; Heparitin Sulfate; Humans; Luciferases; Microscopy, Fluorescence; Mutation; Oligosaccharides; Promoter Regions, Genetic; Proto-Oncogene Proteins B-raf; RNA Interference; Response Elements; Reverse Transcriptase Polymerase Chain Reaction; ras Proteins
PubMed: 21076620
DOI: 10.1593/neo.10790 -
Antiviral Research May 2010Although sulfated polysaccharides potently inhibit the infectivity of herpes simplex virus (HSV) and human immunodeficiency virus in cultured cells, these compounds fail...
Although sulfated polysaccharides potently inhibit the infectivity of herpes simplex virus (HSV) and human immunodeficiency virus in cultured cells, these compounds fail to show protective effects in humans, most likely due to their poor virucidal activity. Herein we report on sulfated oligosaccharide glycosides related to muparfostat (formerly known as PI-88) and their assessment for anti-HSV activity. Chemical modifications based on the introduction of specific hydrophobic groups at the reducing end of a sulfated oligosaccharide chain enhanced the compound's capability to inhibit the infection of cells by HSV-1 and HSV-2 and abrogated the cell-to-cell transmission of HSV-2. Furthermore, modification with a highly lipophilic cholestanyl group provided a compound with virucidal activity against HSV. This glycoside targeted the viral particle and, to a lesser degree, the cell, and exhibited an antiviral mode of action typical for sulfated polysaccharides and virucides, i.e., interference with the virus attachment to cells and irreversible inactivation of virus infectivity, respectively. The virucidal activity was decreased in the presence of human cervical secretions suggesting that higher doses of this glycoside might be needed for in vivo application. Altogether, the sulfated oligosaccharide-cholestanyl glycoside exhibits potent anti-HSV activity and is, therefore, a good candidate for development as a virucide.
Topics: Animals; Antiviral Agents; Bodily Secretions; Cell Line; Chlorocebus aethiops; Herpesvirus 1, Human; Herpesvirus 2, Human; Humans; Microbial Viability; Microscopy, Electron, Transmission; Molecular Structure; Oligosaccharides; Viral Plaque Assay
PubMed: 20176055
DOI: 10.1016/j.antiviral.2010.02.318 -
Canadian Journal of Ophthalmology.... Feb 2010Heparanase, an endoglycosidase, exhibits strong proangiogenic capacity that can induce vascular endothelial growth factor (VEGF) expression in tumour angiogenesis. The...
OBJECTIVE
Heparanase, an endoglycosidase, exhibits strong proangiogenic capacity that can induce vascular endothelial growth factor (VEGF) expression in tumour angiogenesis. The purpose of this study was to evaluate heparanase expression and its relationship with VEGF in streptozotocin (STZ)-induced diabetic rats' retinas.
DESIGN
Experimental study.
PARTICIPANTS
STZ-induced rats and non-diabetic control rats.
METHODS
Heparanase expression was initially evaluated in cultured human retinal microvascular endothelial cells (HRECs) under high-glucose conditions by Western blot. Diabetes was induced in Sprague-Dawley rats by STZ intraperitoneal injection. Retinal heparanase expression was assayed in rats by immunohistochemistry. Heparanase inhibitor (phosphomannopentaose sulfate) was administrated to high-glucose-treated HRECs and diabetic rats. VEGF levels were evaluated in HRECs and retinas using enzyme-linked immunosorbent assay.
RESULTS
Heparanase expression was increased in HRECs under high-glucose conditions compared with controls (p < 0.01). Immunohistochemical studies indicated that heparanase signals were intense in the retinal vascular endothelia of diabetic rats, but faint in those of nondiabetic control rats. Quantitative analysis showed that heparanase protein expression was increased by 3.2-fold in diabetic rats' retinas compared with nondiabetic rats' retinas (p < 0.01). VEGF level was increased, as was heparanase expression, in high-glucose-treated HRECs and in the retinas of diabetic rats, and these increases were significantly decreased by phosphomannopentaose sulfate administration (p < 0.01).
CONCLUSIONS
Heparanase expression was upregulated and associated with an increase of VEGF expression in STZ-induced diabetic rat retinas. The data suggest that heparanase may be involved in the development of diabetic retinopathy and represents a possible novel target for therapeutic intervention.
Topics: Animals; Blotting, Western; Cells, Cultured; Diabetes Mellitus, Experimental; Dose-Response Relationship, Drug; Endothelium, Vascular; Enzyme-Linked Immunosorbent Assay; Glucose; Glucuronidase; Humans; Immunohistochemistry; Male; Oligosaccharides; Rats; Rats, Sprague-Dawley; Retina; Retinal Vessels; Severity of Illness Index; Staining and Labeling; Vascular Endothelial Growth Factor A
PubMed: 20130710
DOI: 10.3129/i09-200 -
Journal of Medicinal Chemistry Feb 2010A series of polysulfated penta- and tetrasaccharide glycosides containing alpha(1-->3)/alpha(1-->2)-linked mannose residues were synthesized as heparan sulfate (HS)...
A series of polysulfated penta- and tetrasaccharide glycosides containing alpha(1-->3)/alpha(1-->2)-linked mannose residues were synthesized as heparan sulfate (HS) mimetics and evaluated for their ability to inhibit angiogenesis. The compounds bound tightly to angiogenic growth factors (FGF-1, FGF-2, and VEGF) and strongly inhibited heparanase activity. In addition, the compounds exhibited potent activity in cell-based and ex vivo assays indicative of angiogenesis, with tetrasaccharides exhibiting activity comparable to that of pentasaccharides. Selected compounds also showed good antitumor activity in vivo in a mouse melanoma (solid tumor) model resistant to the phase III HS mimetic 1 (muparfostat, formerly known as PI-88). The lipophilic modifications also resulted in reduced anticoagulant activity, a common side effect of HS mimetics, and conferred a reasonable pharmacokinetic profile in the rat, as exemplified by the sulfated octyl tetrasaccharide 5. The data support the further investigation of this class of compounds as potential antiangiogenic, anticancer therapeutics.
Topics: Angiogenesis Inhibitors; Animals; Blood Coagulation; Drug Resistance, Neoplasm; Fibroblast Growth Factor 1; Fibroblast Growth Factor 2; Glucuronidase; Glycosides; Heparitin Sulfate; Humans; In Vitro Techniques; Male; Melanoma, Experimental; Mice; Mice, Inbred C57BL; Molecular Mimicry; Neovascularization, Pathologic; Neovascularization, Physiologic; Oligosaccharides; Protein Binding; Rats; Rats, Sprague-Dawley; Structure-Activity Relationship; Sulfuric Acid Esters; Vascular Endothelial Growth Factor A; Xenograft Model Antitumor Assays
PubMed: 20128596
DOI: 10.1021/jm901449m