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HPSE2, the gene‐encoding heparanase 2 (Hpa2), is mutated in urofacial syndrome (UFS), a rare autosomal recessive congenital disease attributed to peripheral neuropathy. Hpa2 lacks intrinsic heparan sulfate (HS)‐degrading activity, the hallmark of heparanase (Hpa1), yet it exhibits a high affinity toward HS, thereby inhibiting Hpa1 enzymatic activity. Hpa2 regulates selected genes that promote normal differentiation, tissue homeostasis, and endoplasmic reticulum (ER) stress, resulting in antitumor, antiangiogenic, and anti‐inflammatory effects. Importantly, stress conditions induce the expression of Hpa2, thus establishing a feedback loop, where Hpa2 enhances ER stress which, in turn, induces Hpa2 expression. In most cases, cancer patients who retain high levels of Hpa2 survive longer than patients bearing Hpa2‐low tumors. Experimentally, overexpression of Hpa2 attenuates the growth of tumor xenografts, whereas Hpa2 gene silencing results in aggressive tumors. Studies applying conditional Hpa2 knockout (cHpa2‐KO) mice revealed an essential involvement of Hpa2 contributed by the host in protecting against cancer and inflammation. This was best reflected by the distorted morphology of the Hpa2‐null pancreas, including massive infiltration of immune cells, acinar to adipocyte trans‐differentiation, and acinar to ductal metaplasia. Moreover, orthotopic inoculation of pancreatic ductal adenocarcinoma (PDAC) cells into the pancreas of Hpa2‐null vs. wild‐type mice yielded tumors that were by far more aggressive. Likewise, intravenous inoculation of cancer cells into cHpa2‐KO mice resulted in a dramatically increased lung colonization reflecting the involvement of Hpa2 in restricting the formation of a premetastatic niche. Elucidating Hpa2 structure–activity‐relationships is expected to support the development of Hpa2‐based therapies against cancer and inflammation. [ABSTRACT FROM AUTHOR]

The human papillomavirus type 16 (HPV16) causes a large fraction of genital and oropharyngeal carcinomas. To maintain the transformed state, the tumor cells must continuously synthesize the E6 and E7 viral oncoproteins, which makes them tumor‐specific antigens. Indeed, specific T cell responses against them have been well documented and CD8+ T cells engineered to express T cell receptors (TCRs) that recognize epitopes of E6 or E7 have been tested in clinical studies with promising results, yet with limited clinical success. Using CD8+ T cells from peripheral blood of healthy donors, we have identified two novel TCRs reactive to an unexplored E618‐26 epitope. These TCRs showed limited standalone cytotoxicity against E618‐26‐HLA‐A*02:01‐presenting tumor cells. However, a single‐signaling domain chimeric antigen receptor (ssdCAR) targeting L1CAM, a cell adhesion protein frequently overexpressed in HPV16‐induced cancer, prompted a synergistic effect that significantly enhanced the cytotoxic capacity of NK‐92/CD3/CD8 cells armored with both TCR and ssdCAR when both receptors simultaneously engaged their respective targets, as shown by live microscopy of 2‐D and 3‐D co‐cultures. Thus, virus‐specific TCRs from the CD8+ T cell repertoire of healthy donors can be combined with a suitable ssdCAR to enhance the cytotoxic capacity of the effector cells and, indirectly, their specificity. [ABSTRACT FROM AUTHOR]

Heparanase is an endo‐β‐glycosidase that cleaves heparan sulfate chains at the level of the glycosidic bond of selected glucuronic acid residues. Heparin fragments, that can compete with heparan sulfate for binding to heparanase, have been reported as weak heparanase inhibitors. To reinforce their inhibitory activity, a known β‐glucuronidase inhibitor has been introduced at their reducing end to directly interfere with the active site of the enzyme. We report here the synthesis of such oligosaccharides, displaying D‐glucaro‐δ‐lactam at their reducing end. Thanks to the trichloroacetimidate glycosylation method, we could devise experimental conditions allowing O‐glycosylation of the lactam ring, and we thus chemically prepared trisaccharides that were further elongated and sulfated using enzymatic methods. Heparanase inhibitory activity was not significantly improved by the presence of the D‐glucaro‐δ‐lactam ring. [ABSTRACT FROM AUTHOR]

Further, factor VIII (FVIII), a potent and key factor in the coagulation process, is greatly increased in ICU patients with COVID-19.16 In this setting, it has been proposed that the systemic hyperinflammation observed in severe COVID-19 is comparable to a cytokine release syndrome (CRS), or cytokine storm. The coronavirus disease 2019 (COVID-19) pandemic, a viral illness caused by the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2),1 has produced at the time of this writing nearly 33 million cases of infection, with over a million deaths in 235 countries,2 causing an unprecedented burden on healthcare systems and a severe global socioeconomic crisis. COVID-19-induced endotheliitis: emerging evidence and possible therapeutic strategies Most reported cases are asymptomatic or present with mild symptoms; however, 7-26% of hospitalised patients experience severe disease, often requiring admission to intensive care units (ICUs), with progressive multiple organ dysfunction and high mortality.3-5 Such differences in clinical outcomes have led physicians to initiate diverse pharmacological therapies at various stages of the disease, generating challenges as to the most appropriate therapeutic choice for COVID-19. [Extracted from the article]

On March 11, 2020, the World Health Organization declared its assessment of coronavirus disease 2019 (COVID‐19) as a global pandemic. However, specific anti‐severe acute respiratory syndrome‐coronavirus 2 (SARS‐CoV‐2) drugs are still under development, and patients are managed by multiple complementary treatments. We performed a retrospective analysis to compare and evaluate the effect of low molecular weight heparin (LMWH) treatment on disease progression. For this purpose, the clinical records and laboratory indicators were extracted from electronic medical records of 42 patients with COVID‐19 (21 of whom were treated with LMWH, and 21 without LMWH) hospitalized (Union Hospital of Huazhong University of Science and Technology) from February 1 to March 15, 2020. Changes in the percentage of lymphocytes before and after LMWH treatment were significantly different from those in the control group (P = 0.011). Likewise, changes in the levels of D‐dimer and fibrinogen degradation products in the LMWH group before and after treatment were significantly different from those in the control group (P = 0.035). Remarkably, IL‐6 levels were significantly reduced after LMWH treatment (P = 0.006), indicating that, besides other beneficial properties, LMWH may exert an anti‐inflammatory effect and attenuate in part the "cytokine storm" induced by the virus. Our results support the use of LMWH as a potential therapeutic drug for the treatment of COVID‐19, paving the way for a subsequent well‐controlled clinical study. [ABSTRACT FROM AUTHOR]

Heparanase is an endo‐β‐d‐glucuronidase that cleaves heparan sulfate (HS) side chains of heparan sulfate proteoglycans. Compelling evidence tie heparanase levels with all steps of tumor formation including tumor initiation, growth, metastasis and chemo‐resistance, likely involving augmentation of signaling pathways and gene transcription. In order to reveal the molecular mechanism(s) underlying the protumorigenic properties of heparanase, we established an inducible (Tet‐on) system in U87 human glioma cells and applied gene array methodology in order to identify genes associated with heparanase induction. We found that CD24, a mucin‐like cell adhesion protein, is consistently upregulated by heparanase and by heparanase splice variant devoid of enzymatic activity, whereas heparanase gene silencing was associated with decreased CD24 expression. This finding was further substantiated by a similar pattern of heparanase and CD24 immunostaining in glioma patients (Pearson's correlation; R = 0.66, p = 0.00001). Noteworthy, overexpression of CD24 stimulated glioma cell migration, invasion, colony formation in soft agar and tumor growth in mice suggesting that CD24 functions promote tumor growth. Likewise, anti‐CD24 neutralizing monoclonal antibody attenuated glioma tumor growth, and a similar inhibition was observed in mice treated with a neutralizing mAb directed against L1 cell adhesion molecule (L1CAM), a ligand for CD24. Importantly, significant shorter patient survival was found in heparanase‐high/CD24‐high tumors vs. heparanase‐high/CD24‐low tumors for both high‐grade and low‐grade glioma (p = 0.02). Our results thus uncover a novel heparanase–CD24–L1CAM axis that plays a significant role in glioma tumorigenesis. What's new? The heparanase enzyme has been associated with carcinogenesis in many ways but how it affects glioma development remains unknown. Here, the authors find that heparanase overexpression enhances the expression of the mucin‐like cell adhesion protein CD24. CD24 promotes glioma growth while anti‐CD24 antibodies attenuate the growth of glioma xenografts, providing a molecular mechanism underlying the protumorigenic properties of heparanase in glioma. [ABSTRACT FROM AUTHOR]

Heparan sulfate (HS) mediates the activity of various growth factors including TGF-β. Heparanase is an endo-glucuronidase that specifically cleaves and modifies HS structure. In this study, we examined the effect of heparanase expression on TGF-β1-dependent signaling activities. We found that overexpression of heparanase in human tumor cells (i.e., Fadu pharyngeal carcinoma, MCF7 breast carcinoma) attenuated TGF-β1-stimulated Smad phosphorylation and led to a slower cell proliferation. TGF-β1-stimulated Akt and Erk phosphorylation was also affected in the heparanase overexpression cells. This effect involved the enzymatic activity of heparanase, as overexpression of mutant inactive heparanase did not affect TGF-β1 signaling activity. Analysis of HS isolated from Fadu cells revealed an increase in sulfation of the HS that had a rapid turnover in cells overexpressing heparanase. It appears that the structural alterations of HS affect the ability of TGF-β1 to signal via its receptors and elicit a growth response. Given that heparanase expression promotes tumor growth in most cancers, this finding highlights a crosstalk between heparanase, HS, and TGF-β1 function in tumorigenesis. [ABSTRACT FROM AUTHOR]

Because of its impact on multiple biological pathways, heparanase has emerged as a major regulator of cancer, inflammation and other disease processes. Heparanase accomplishes this by degrading heparan sulfate which regulates the abundance and location of heparin-binding growth factors thereby influencing multiple signaling pathways that control gene expression, syndecan shedding and cell behavior. In addition, heparanase can act via nonenzymatic mechanisms that directly activate signaling at the cell surface. Clinical trials testing heparanase inhibitors as anticancer therapeutics are showing early signs of efficacy in patients further emphasizing the biological importance of this enzyme. This review focuses on recent developments in the field of heparanase regulation of cancer and inflammation, including the impact of heparanase on exosomes and autophagy, and novel mechanisms whereby heparanase regulates tumor metastasis, angiogenesis and chemoresistance. In addition, the ongoing development of heparanase inhibitors and their potential for treating cancer and inflammation are discussed. [ABSTRACT FROM AUTHOR]

The pulmonary vasculature constitutively expresses the integrin lymphocyte function-associated antigen-1 ligands intercellular adhesion molecule (ICAM)-1 and -2. In this study, effector T cells were temporarily entrapped by the lung vasculature on their way to inflamed lymph nodes, and this entrapment was strongly reduced in ICAM-1 and -2 double-deficient mice (79 and 86% reduction for CD8+ and CD4+ effectors, respectively, compared with wild-type mice). Although the pulmonary vasculature has been suggested to be masked by the heparan sulfate-containing glycocalyx, which is susceptible to heparanase-mediated shedding, lung and lymphocyte heparanase have been found to be unnecessary for this entrapment. Systemic LPS induced rapid neutrophil entrapment in the lung vasculature, but in contrast to T-cell entrapment, this sequestration was ICAM-1, ICAM-2, and heparanase independent. Furthermore, neutrophil migration into the bronchoalveolar space induced by LPS inhalation and LPS-induced leakage of red blood cells into this space were not dependent on lung ICAMs or heparanase activity. Nevertheless, heparanase was critical for neutrophil accumulation in smoke-exposed lungs. Our results indicate that, whereas T cells use ICAM-1 and -2 for temporary pulmonary entrapment, neutrophils get sequestered and extravasate into inflamed lungs independent of ICAMs. This is the first demonstration that the pulmonary vasculature is differentially recognized by T cells and neutrophils. [ABSTRACT FROM AUTHOR]

Heparanase, the exclusive mammalian heparan sulfate-degrading enzyme, has been suggested to be utilized by leukocytes to penetrate through the dense basement membranes surrounding blood venules. Despite its established role in tumor cell invasion, heparanase function in leukocyte extravasation has never been demonstrated. We found that TH1/TC1-type effector T cells are highly enriched for this enzyme, with a 3.6-fold higher heparanase mRNA expression compared with naive lymphocytes. Using adoptive transfer of wild-type and heparanase-deficient effector T cells into inflamed mice, we show that T-cell heparanase was not required for extravasation inside inflamed lymph nodes or skin. Leukocyte extravasation through acute inflamed skin vessels was also heparanase independent. Furthermore, neutrophils emigrated to the inflamed peritoneal cavity independently of heparanase expression on either the leukocytes or on the endothelial and mesothelial barriers, and overexpression of the enzyme on neutrophils did not facilitate their emigration. However, heparanase absence significantly reduced monocyte emigration into the inflamed peritoneal cavity. These results collectively suggest that neither leukocyte nor endothelial heparanase is required for T-cell and neutrophil extravasation through inflamed vascular barriers, whereas this enzyme is required for optimal monocyte recruitment to inflamed peritoneum. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Heparanase is an endoglycosidase that specifically cleaves heparan sulphate side chains of heparan sulphate proteoglycans, activity that is strongly implicated in cell migration and invasion associated with tumour metastasis, angiogenesis and inflammation. Heparanase up-regulation was documented in an increasing number of human carcinomas, correlating with reduced post-operative survival rate and enhanced tumour angiogenesis. Expression and significance of heparanase in human sarcomas has not been so far reported. Here, we applied the Ewing's sarcoma cell line TC71 and demonstrated a potent inhibition of cell invasion in vitro and tumour xenograft growth in vivo upon treatment with a specific inhibitor of heparanase enzymatic activity (compound SST0001, non-anticoagulant N-acetylated, glycol split heparin). Next, we examined heparanase expression and cellular localization by immunostaining of a cohort of 69 patients diagnosed with Ewing's sarcoma. Heparanase staining was noted in all patients. Notably, heparanase staining intensity correlated with increased tumour size ( P = 0.04) and with patients' age ( P = 0.03), two prognostic factors associated with a worse outcome. Our study indicates that heparanase expression is induced in Ewing's sarcoma and associates with poor prognosis. Moreover, it encourages the inclusion of heparanase inhibitors ( i.e. SST0001) in newly developed therapeutic modalities directed against Ewing's sarcoma and likely other malignancies. [ABSTRACT FROM AUTHOR]

Background. Metastases formation depends on the ability of tumor cells to invade basement membranes in a process involving enzymes capable of degrading extracellular matrix components. Methods. We examined the expression of heparanase in oral carcinomas and correlated its staining extent, intensity, and cellular localization with patients’ outcome. Results. 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. Conclusion. Expression level and cellular localization of heparanase could serve as an important diagnostic marker in patients with oral cancer. [ABSTRACT FROM AUTHOR]

Heparanase up‐regulation was documented in an increasing number of human carcinomas, associated with poor prognosis. The purpose of the current study was to identify mechanisms responsible for heparanase induction. We provide evidence that heparanase expression is regulated at the post‐transcriptional level by sequences at the 3’ untranslated region (3’ UTR) of the gene. Constructing the 3’ UTR immediately following the heparanase cDNA reduces heparanase enzymatic activity and protein levels, resulting in decreased cellular invasion capacity. We further identified a 185‐bp sequence within the 3’ UTR that mediates heparanase down‐regulation, and characterized an adenine (A)/uracil (U)‐rich consensus element (ARE) within this region. Deletion of the entire 185‐bp region or the ARE eliminated the inhibitory effect of the 3’ UTR, resulting in elevated heparanase levels and formation of larger tumor xenografts indistinguishable from those produced by heparanase‐overex‐pressing cells in terms of size, vascularization, and Akt activation. These results suggest that loss of the ARE is an important regulatory mechanism contributing to hepara‐nase induction in human cancer.—Arvatz, G., Barash, U., Nativ, O., Ilan, N., Vlodavsky, I. Post‐transcriptional regulation of heparanase gene expression by a 3’ AU‐rich element. FASEB J. 24, 4969–4976 (2010). www.fasebj.org [ABSTRACT FROM AUTHOR]

Heparanase is an endo-β-d-glucuronidase capable of cleaving heparan sulfate side chains at a limited number of sites, yielding heparan sulfate fragments of still appreciable size. Importantly, heparanase activity correlates with the metastatic potential of tumor-derived cells, attributed to enhanced cell dissemination as a consequence of heparan sulfate cleavage and remodeling of the extracellular matrix and basement membrane underlying epithelial and endothelial cells. Similarly, heparanase activity is implicated in neovascularization, inflammation and autoimmunity, involving the 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 heparan sulfate cleavage by heparanase is required for structural remodeling of the extracellular matrix, thereby facilitating cell invasion. Progress in the field has expanded the scope of heparanase function and its significance in tumor progression and other pathologies. Notably, although 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, inactive heparanase was noted to facilitate adhesion and migration of primary endothelial cells and to promote phosphorylation of signaling molecules such as Akt and Src, facilitating gene transcription (i.e. vascular endothelial growth factor) and phosphorylation of selected Src substrates (i.e. endothelial growth factor receptor). The concept of enzymatic activity-independent function of heparanase gained substantial support by the recent identification of the heparanase C-terminus domain as the molecular determinant behind its signaling capacity. Identification and characterization of a human heparanase splice variant (T5) devoid of enzymatic activity and endowed with protumorigenic characteristics, elucidation of cross-talk between heparanase and other extracellular matrix-degrading enzymes, and identification of single nucleotide polymorphism associated with heparanase expression and increased risk of graft versus host disease add other layers of complexity to heparanase function in health and disease. [ABSTRACT FROM AUTHOR]

Heparanase is a mammalian endo-β-D-glucuronidase that can cleave heparan sulfate side chains, an activity strongly implicated in tumor cell dissemination. The current study aimed to identify and characterize heparanase splice variants. LEADS, Compugen's alternative splicing modeling platform (Compugen, Tel Aviv, Israel), was used to search for splice variants in silico; tumor-derived cell lines (i.e., CAG myeloma) and tumor biopsies were utilized to validate T5 expression in vivo; signaling (i.e., Src phosphorylation) was evaluated following T5 gene silencing or overexpression and correlated with cell proliferation, colony formation, and tumor xenograft development. A novel spliced form of human heparanase, termed T5, was identified. In this splice variant, 144 bp of intron 5 are joined with exon 4, which results in a truncated, enzymatically inactive protein. T5 overexpression resulted in increased cell proliferation and larger colonies in soft agar, mediated by Src activation. Furthermore, T5 overexpression markedly enhanced tumor xenograft development. T5 expression is up-regulated in 75% of human renal cell carcinoma biopsies examined, which suggests that this splice variant is clinically relevant. Controls included cells overexpressing wild-type heparanase or an empty plasmid and normal-looking tissue adjacent the carcinoma lesion. T5 is a novel functional splice variant of human heparanase endowed with protumorigenic characteristics. [ABSTRACT FROM AUTHOR]

The different clinical entities of osteochondromas, hereditary multiple exostoses (HME) and non-familial solitary exostosis, are known to express localized exostoses in their joint metaphyseal cartilage. In the current study biopsies of osteochondromas patients were screened with respect to a number of cellular and molecular parameters. Specifically, cartilaginous biopsy samples of nine HME patients, 10 solitary exostosis patients and 10 articular cartilages of control subjects were collected and cell cultures were established. Results obtained showed that one of the two HME samples that underwent DNA sequencing analysis (HME-1) had a novel mutation for an early stop codon, which led to an aberrant protein, migrating at a lower molecular weight position. The EXT-1 mRNA and protein levels in chondrocyte cultures derived from all nine HME patients were elevated, compared with solitary exostosis patients or control subjects. Furthermore, cell cultures of HME patients had significantly decreased pericellular heparan sulphate (HS) in comparison with cultures of solitary exostosis patients or control subjects. Immunohistochemical staining of tissue sections and Western blotting of cell cultures derived from HME patients revealed higher levels of heparanase compared with solitary exostosis patients and of control subjects. Further investigations are needed to determine whether the low pericellular HS levels in HME patients stem from decreased biosynthesis of HS, increased degradation or a combination of both. In conclusion, it appears that due to a mutated glycosyltransferase, the low content of pericellular HS in HME patients leads to the anatomical deformations with exostoses formation. Hence, elevation of HS content in the pericellular regions should be a potential molecular target for correction. [ABSTRACT FROM AUTHOR]

Background: Heparanase is an endo-beta-D-glucuronidase that is capable of cleaving heparan sulfate (HS) side chains at a limited number of sites, yielding HS fragments of still appreciable size (approximately 5-7 kDa). Heparanase activity has been detected frequently in several cell types and tissues. Heparanase activity correlates with the metastatic potential of tumor-derived cells, a correlation that has been attributed to enhanced cell dissemination as a consequence of HS cleavage and remodeling of the extracellular matrix barrier.Methods: In this study, the authors examined heparanase expression in 114 patients with lung cancer by means of immunohistochemistry and correlated clinical-pathologic data with heparanase immunostaining and cellular localization.Results: Heparanase was overexpressed in 75% of the study patients. Heparanase expression was correlated with lung cancer lymph node status and metastasis classification (P = .04 and P = .01, respectively) and was correlated inversely with patient survival (P = .007). It is noteworthy that this adverse effect depended largely on the cellular localization of heparanase. Thus, whereas cytoplasmic staining of heparanase is associated with a poor prognosis, nuclear heparanase predicts a favorable outcome for patients with lung cancer.Conclusions: The current findings suggest that heparanase expression and cellular localization are decisive for lung cancer patients' prognosis, most likely because of heparanase-mediated tumor cell dissemination by blood and lymph vessels. [ABSTRACT FROM AUTHOR]

Background Heparanase is an endo-β-D-glucuronidase that cleaves heparan sulfate saccharide chains. The enzyme promotes cell adhesion, migration and invasion, and was shown to play a significant role in cancer metastasis and angiogenesis. Methods The present study focuses on the involvement of heparanase in autoimmunity, applying the murine non-obese diabetic (NOD) model, a T-cell-dependent disease often used to investigate the pathophysiology of type 1 diabetes. Results It was found that intra-peritoneal administration of heparanase ameliorated the clinical signs of the disease. In vitro studies revealed that heparanase has an inhibitory effect on the activation of T-cells through modulation of their repertoire of cytokines indicated by a marked increase in the levels of IL-4 and IL-10, and a parallel decrease in IL-12, tumour necrosis factor-alpha (TNF-α) and interferon-gamma (IFN-γ). Conclusions We suggest that heparanase induces a shift from a Th1- to Th2-phenotype, resulting in inhibition of diabetes in NOD mice and possibly other autoimmune disorders. Copyright © 2008 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Objective: To assess the expression of heparanase in the different stages leading to endometrial cancer.Methods: The 38 examined specimens included adenocarcinoma, hyperplasia, and normal endometrium specimens. Heparanase, estrogen, and progesterone receptor expressions were analyzed immunohistochemically and the intensity was scored.Results: Secretory normal endometrium and simple hyperplasia specimens expressed the lowest mean values of expression (1.00 and 0.63, respectively); the complex hyperplasia specimens and G2 endometrioid adenocarcinoma showed the highest values of expression (2.33 and 2.71, respectively). A linear trend (P=0.005) of heparanase expression was observed when comparing the normal endometrium and simple hyperplasia group with the complex hyperplasia+G1 carcinoma group and the G2+G3 carcinoma group. Evaluation of atrophic and inactive endometrium compared with papillary serous carcinomas yielded no significant differences. We found no significant correlation between heparanase expression and estrogen receptor or progesterone receptor expression.Conclusion: Heparanase expression was tightly regulated in endometrial tumorigenesis. [ABSTRACT FROM AUTHOR]

The article presents a study which investigated the up-regulation of heparanase in tongue cancer. Using immunohistochemistry, the authors analyzed heparanase expression in 60 consenting tongue (mobile) cancer patients. They also analyzed the heparanase levels in the saliva of both healthy controls and tongue cancer patients via a novel heparanase enzyme-linked immunosorbent assay method. They found that heparanase staining was positive in 92% and negative in 8% of the tumors and staining intensity correlated with tumor size and tumor stage.

Heparanase is a mammalian endo-β-D-glucuronidase capable of cleaving HS side chains at a limited number of sites, activity that is strongly implicated in tumor metastasis, neovascularization, inflammation, and autoimmunity. Clinically, up-regulation of heparanase mRNA and protein expression has been documented in a variety of primary human tumors, correlating with reduced postoperative survival and increased lymph node and distant metastasis, thus providing strong clinical support for the prometastatic feature of the enzyme and making it an attractive target for the development of anticancer and anti-inflammatory drugs. Screening a panel of monoclonal antibodies for their ability to inhibit heparanase enzymatic activity, we noted that one hybridoma, 6F8, exhibited the opposite effect and significantly enhanced heparanase activity. Here, we provide evidence that antibody 6F8 enhances the activity of recombinant and cellular heparanase, facilitates invasion of tumor-derived cells in vitro, and improves wound healing in a mouse punch model in vivo. These results support a role of heparanase in the course of wound healing and, moreover, suggest that monoclonal antibodies can be applied clinically for the enhancement, rather than inhibition, of certain enzymes. [ABSTRACT FROM AUTHOR]

Vascular cell adhesion molecules, P- and L-selectins, facilitate metastasis of cancer cells in mice by mediating interactions with platelets, endothelium, and leukocytes. Heparanase is an endoglycosidase that degrades heparan sulfate of extracellular matrix, thereby promoting tumor invasion and metastasis. Heparin is known to efficiently attenuate metastasis in different tumor models. Here we identified modified, nonanticoagulant species of heparin that specifically inhibit selectin-mediated cell-cell interactions, heparanase enzymatic activity, or both. We show that selective inhibition of selectin interactions or heparanase with specific heparin derivatives in mouse models of MC-38 colon carcinoma and B16-BL6 melanoma attenuates metastasis. Selectin-specific heparin derivatives attenuated metastasis of MC-38 carcinoma, but heparanase-specific derivatives had no effect, in accordance with the virtual absence of heparanase activity in these cells. Heparin derivatives had no further effect on metastasis in mice deficient in P- and L-selectin, indicating that selectins are the primary targets of heparin antimetastatic activity. Selectin-specific and heparanase-specific derivatives attenuated metastasis of B16-BL6 melanomas to a similar extent. When mice were injected with a derivative containing both heparanase and selectin inhibitory activity, no additional attenuation of metastasis could be observed. Thus, selectin-specific heparin derivatives efficiently attenuated metastasis of both tumor cell types whereas inhibition of heparanase led to reduction of metastasis only in tumor cells producing heparanase. [ABSTRACT FROM AUTHOR]

A family of biopolymers engineered to protect and stabilize heparin binding growth factors (HBGFs) show remarkable properties as wound healing agents in several in vivo tissue repair models to the extend that damaged tissues would recover almost its initial aspect and properties. These polymers where named RGTA for regenerating agents and proposed to act in vivo by enhancing the bioavailability of HBGFs at the site of the injury. To provide support for this hypothesis, we studied interaction of RGTA with FGF‐2, taken as the paradigm of HBGFs, and its high‐ and low‐affinity receptors as well as its ability to inhibit heparanase activity. We show that RGTA is comparable to heparin as it favors FGF‐2 binding to FGFR‐1 and FGF‐2 dimerization and potentiates FGF‐2‐induced mitogenic activity. Furthermore, we show that RGTA inhibits the release of FGF‐2 from its extracellular matrix storage sites by heparanase. Our data provide new evidence to support that RGTA may act in vivo both by enhancing HBGF activity and preserving HBGF availability by protecting the matrix low affinity heparan sulfates from rapid heparanase degradation. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res, 2006 [ABSTRACT FROM AUTHOR]

Heparan sulfate proteoglycans (HSPGs) are ubiquitous macromolecules. In bone, they are associated with cell surfaces and the extracellular matrix (ECM). The heparan sulfate (HS) chains of HSPGs bind a multitude of bioactive molecules, thereby controlling normal and pathologic processes. The HS-degrading endoglycosidase, heparanase, has been implicated in processes such as inflammation, vascularization associated with wound healing and malignancies, and cancer metastasis. Here we show progressive mRNA expression of the hpa gene (encoding heparanase) in murine bone marrow stromal cells undergoing osteoblastic (bone forming) differentiation and in primary calvarial osteoblasts. Bone marrow stromal cells derived from transgenic mice expressing recombinant human heparanase (rh-heparanase) and MC3T3 E1 osteoblastic cells exposed to soluble rh-heparanase spontaneously undergo osteogenic differentiation. In addition, the transgenic bone marrow stromal cells degrade HS chains. In wild-type (WT) and hpa-transgenic (hpa-tg) mice, heparanase is weakly expressed throughout the bone marrow with a substantial increase in osteoblasts and osteocytes, especially in the hpa-tg mice. Heparanase expression was absent in osteoclasts. Micro-computed tomographic and histomorphometric skeletal analyses in male and female hpa-tg versus WT mice show markedly increased trabecular bone mass, cortical thickness, and bone formation rate, but no difference in osteoclast number. Collectively, our data suggest that proteoglycans tonically suppress osteoblast function and that this inhibition is alleviated by HS degradation with heparanase. J. Cell. Physiol. © 2006 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Abstract: Heparanase is an endo-β-glucuronodase involved in cleavage of heparan sulfate side chains, activity that is strongly implicated in cell dissemination associated with tumor metastasis and inflammation. Heparanase is first synthesized as a latent 65kDa precursor that is converted into an active enzyme upon proteolytic processing. Previously, we have reported that elevation of the lysosomal pH results in complete inhibition of heparanase processing, suggesting that lysosomal protease(s) and acidic pH conditions are required for heparanase processing. Here, we adopted a cell fractionation approach and provide evidence that incubation of the pro-enzyme with lysosome/endosome, but not with cytoplasmic fractions resulted in processing and activation of the 65kDa latent heparanase. Moreover, while the water soluble lysosome/endosome fraction exhibited no apparent processing activity, heparanase processing by the water insoluble lysosome/endosome membrane fraction was readily detected and exhibited the expected pH dependency. [Copyright &y& Elsevier]

Orchestration of the rapid formation and reorganization of new tissue observed in wound healing involves not only cells and polypeptides but also the extracellular matrix (ECM) microenvironment. The ability of heparan sulfate (HS) to interact with major components of the ECM suggests a key role for HS in maintaining the structural integrity of the ECM. Heparanase, an endoglycosidase-degrading HS in the ECM and cell surface, is involved in the enzymatic machinery that enables cellular invasion and release of HS-bound polypeptides residing in the ECM. Bioavailabilty and activation of multitude mediators capable of promoting cell migration, proliferation, and neovascularization are of particular importance in the complex setting of wound healing. We provide evidence that heparanase is normally expressed in skin and in the wound granulation tissue. Heparanase stimulated keratinocyte cell migration and wound closure in vitro. Topical application of recombinant heparanase significantly accelerated wound healing in a flap/punch model and markedly improved flap survival. These heparanase effects were associated with enhanced wound epithelialization and blood vessel maturation. Similarly, a marked elevation in wound angiogenesis, evaluated by MRI analysis and histological analyses, was observed in heparanase-overexpressing transgenic mice. This effect was blocked by a novel, newly developed, heparanase-inhibiting glycol-split fragment of heparin. These results clearly indicate that elevation of heparanase levels in healing wounds markedly accelerates tissue repair and skin survival that are mediated primarily by an enhanced angiogenic response. [ABSTRACT FROM AUTHOR]

We have generated homozygous transgenic mice (hpa-tg) overexpressing human heparanase (endo-β-D-glucuronidase) in all tissues and characterized the involvement of the enzyme in tissue morphogenesis, vascularization, and energy metabolism. Biochemical analysis of heparan sulfate (HS) isolated from newborn mice and adult tissues revealed a profound decrease in the size of HS chains derived from hpa-tg vs. control mice. Despite this, the mice appeared normal, were fertile, and exhibited a normal life span. A significant increase in the number of implanted embryos was noted in the hpa-tg vs. control mice. Overexpression of heparanase resulted in increased levels of urinary protein and creatinine, suggesting an effect on kidney function, reflected also by electron microscopy examination of the kidney tissue. The hpa-tg mice exhibited a reduced food consumption and body weight compared with control mice. The effect of heparanase on tissue remodeling and morphogenesis was best demonstrated by the phenotype of the hpa-tg mammary glands, showing excess branching and widening of ducts associated with enhanced neovascularization and disruption of the epithelial basement membrane. The hpa-tg mice exhibited an accelerated rate of hair growth, correlated with high expression of heparanase in hair follicle keratinocytes and increased vascularization. Altogether, characterization of the hpa-tg mice emphasizes the involvement of heparanase and HS in processes such as embryonic implantation, food consumption, tissue remodeling, and vascularization. [ABSTRACT FROM AUTHOR]

Connective tissue-activating peptide III (CTAP III), a CXC chemokine derived from the chemokine precursor platelet basic protein (PBP) by proteolytic cleavage, has been identified in platelets, activated macrophages, neutrophils and T lymphocytes. CTAP III can support stem cell-derived haematopoiesis yet inhibits the proliferation of committed megakaryocyte (MK) progenitors. This investigation was aimed at characterizing CTAP III expression in human MKs and determining it's role in MK differentiation. We report high expression of CTAP III in mature human bone marrow (BM) MKs and megakaryoblast cell lines following differentiation induction with phorbol ester 12-myristate 13-acetate (PMA). Immunostaining with anti-CTAP III antibodies demonstrated its prominent presence in platelet producing zones in the cytoplasm and intense staining around the periphery of the large BM MKs. In cultures of logarithmically growing megakaryoblast cell lines DAMI, CHRF-288 or MEG01, which contain primarily 2N cells, only 15% of the cells expressed CTAP III. The addition of PMA stimulated high levels of CTAP III after 24 h in more than 75% of the cells, being expressed in both the 2N and large polyploid MKs. Reverse transcription polymerase chain reaction (RT-PCR) revealed upregulation of CTAP III mRNA after only 1 h of exposure to PMA that was sustained for 24 h. In the bone marrow of idiopathic thrombocytopenic pupura (ITP) patients undergoing accelerated MK maturation and thrombopoiesis, 99% of large MKs and 95% of small MKs expressed high levels of CTAP III. While the biological function of this chemokine in MKs is not known, these studies demonstrate that molecular upregulation of CTAP III in MKs is associated with maturation and, as with other chemokines, may be involved in proliferation arrest and cellular interactions with extracellular matrix and platelet production. [ABSTRACT FROM AUTHOR]