heparitin-sulfate and Liver-Neoplasms

heparitin-sulfate has been researched along with Liver-Neoplasms* in 44 studies

Reviews

2 review(s) available for heparitin-sulfate and Liver-Neoplasms

ArticleYear
Heparanase-1: From Cancer Biology to a Future Antiviral Target.
    Viruses, 2023, 01-14, Volume: 15, Issue:1

    Heparan sulfate proteoglycans (HSPGs) are a major constituent of the extracellular matrix (ECM) and are found to be implicated in viral infections, where they play a role in both cell entry and release for many viruses. The enzyme heparanase-1 is the only known endo-beta-D-glucuronidase capable of degrading heparan sulphate (HS) chains of HSPGs and is thus important for regulating ECM homeostasis. Heparanase-1 expression is tightly regulated as the uncontrolled cleavage of HS may result in abnormal cell activation and significant tissue damage. The overexpression of heparanase-1 correlates with pathological scenarios and is observed in different human malignancies, such as lymphoma, breast, colon, lung, and hepatocellular carcinomas. Interestingly, heparanase-1 has also been documented to be involved in numerous viral infections, e.g., HSV-1, HPV, DENV. Moreover, very recent reports have demonstrated a role of heparanase-1 in HCV and SARS-CoV-2 infections. Due to the undenied pro-carcinogenic role of heparanase-1, multiple inhibitors have been developed, some reaching phase II and III in clinical studies. However, the use of heparanase inhibitors as antivirals has not yet been proposed. If it can be assumed that heparanase-1 is implicated in numerous viral life cycles, its inhibition by specific heparanase-acting compounds should result in a blockage of viral infection. This review addresses the perspectives of using heparanase inhibitors, not only for cancer treatment, but also as antivirals. Eventually, the development of a novel class antivirals targeting a cellular protein could help to alleviate the resistance problems seen with some current antiretroviral therapies.

    Topics: Antiviral Agents; Biology; Carcinoma, Hepatocellular; COVID-19; Glucuronidase; Heparan Sulfate Proteoglycans; Heparitin Sulfate; Humans; Liver Neoplasms; SARS-CoV-2

2023
[Proteoglycans in the liver].
    Magyar onkologia, 2004, Volume: 48, Issue:3

    Proteoglycans are macromolecules formed by a protein core to which sugar chains are covalently attached. They are present on the cell surface and in the ECM of living things. In normal liver syndecan-1 is the dominant transmembrane proteoglycan, trace amounts of ECM proteoglycans are in the stromal components. The amounts of proteoglycans we studied increase in liver cirrhosis. In liver cancer abnormal localization of syndecan-1 and stroma rich in agrin was characteristic. The core proteins as well as the sugar chains of proteoglycans interact with and modulate the effect of regulatory factors. This implies that structural alterations of proteoglycans contribute to the development of malignant phenotype. Heparan sulfate chains of liver cancer are undersulfated with decreased or altered biological activity. Their binding capacity for transcription factor decreases, and they do not inhibit topoisomerase I enzyme. Truncated form of syndecan-1 lacking the extracellular domain of the molecule induces differentiation of hepatoma cell line and inhibits the shedding of syndecan-1. This phenomenon calls attention to the importance of syndecan-1 shedding in the regulation of cell behavior.

    Topics: Animals; Cell Differentiation; Cell Transformation, Neoplastic; Heparitin Sulfate; Humans; Liver; Liver Cirrhosis; Liver Diseases; Liver Neoplasms; Membrane Glycoproteins; Proteoglycans; Signal Transduction; Syndecan-1; Syndecans

2004

Trials

1 trial(s) available for heparitin-sulfate and Liver-Neoplasms

ArticleYear
Effect of Hydroxyethyl Starch Loading on Glycocalyx Shedding and Cerebral Metabolism During Surgery.
    The Journal of surgical research, 2020, Volume: 246

    Fluid therapy influences glycocalyx shedding; however, the effect of this intervention on glycocalyx shedding in patients with glioma remains unclear. In this study, we have investigated glycocalyx shedding and cerebral metabolism during colloid loading in patients with and without glioma.. Forty patients undergoing general anesthesia were assigned to the glioma brain group (n = 20) or the normal brain group (n = 20); patients in the normal brain group were undergoing partial hepatectomy to treat liver cancer. All patients were subjected to 15 mL/kg hydroxyethyl starch (HES) loading after the induction of anesthesia. Glycocalyx shedding, reflected by syndecan-1 and heparan sulfate levels at the jugular venous bulb, was measured in both groups. We also evaluated cerebral metabolism parameters, including jugular venous oxygen saturation (SjvO. Our results showed that patients in the glioma brain group had lower preoperative basal syndecan-1 shedding in plasma than patients in the normal brain group. The hematocrit (Hct)-corrected syndecan-1 level was significantly increased after 15 mL/kg HES fluid administration (19.78 ± 3.83 ng/mL) compared with the Hct-correct baseline syndecan-1 level (15.67 ± 2.35 ng/mL) in patients in the glioma brain group. Similarly, for patients in the normal brain group, Hct-corrected syndecan-1 level was significantly increased after HES loading (34.71 ± 12.83 ng/mL) compared with the baseline syndecan-1 level (26.07 ± 12.52 ng/mL). However, there were no intergroup or intragroup differences in Hct-corrected heparan sulfate levels at any time point. Our study also showed that the SjvO. Preoperative 15 mL/kg HES loading had similar effects on systemic glycocalyx shedding in both the glioma brain and normal brain groups, although patients in the normal brain group had higher levels of plasma syndecan-1. Furthermore, the intraoperative anesthetic management may substantially influence cerebral metabolism in patients with glioma.

    Topics: Adult; Brain; Brain Neoplasms; Endothelium, Vascular; Female; Fluid Therapy; Glioma; Glycocalyx; Heparitin Sulfate; Humans; Hydroxyethyl Starch Derivatives; Intraoperative Care; Jugular Veins; Liver Neoplasms; Male; Middle Aged; Preoperative Care; Prospective Studies; Syndecan-1

2020

Other Studies

41 other study(ies) available for heparitin-sulfate and Liver-Neoplasms

ArticleYear
Expression of glycosaminoglycans in cirrhotic liver and hepatocellular carcinoma-a pilot study including etiology.
    Analytical and bioanalytical chemistry, 2022, Volume: 414, Issue:13

    Chronic liver diseases have both high incidence and mortality rates; therefore, a deeper understanding of the underlying molecular mechanisms is essential. We have determined the content and sulfation pattern of chondroitin sulfate (CS) and heparan sulfate (HS) in human hepatocellular carcinoma and cirrhotic liver tissues, considering the etiology of the diseases. A variety of pathological conditions such as alcoholic liver disease, hepatitis B and C virus infections, and primary sclerosing cholangitis were studied. Major differences were observed in the total abundance and sulfation pattern of CS and HS chains. For example, the 6-O-sulfation of CS is fundamentally different regarding etiologies of cirrhosis, and a 2-threefold increase in HS N-sulfation/O-sulfation ratio was observed in hepatocellular carcinoma compared to cirrhotic tissues.

    Topics: Carcinoma, Hepatocellular; Chondroitin Sulfates; Glycosaminoglycans; Heparitin Sulfate; Humans; Liver Cirrhosis; Liver Neoplasms; Pilot Projects

2022
Syndecan-1 Promotes Hepatocyte-Like Differentiation of Hepatoma Cells Targeting Ets-1 and AP-1.
    Biomolecules, 2020, 09-23, Volume: 10, Issue:10

    Syndecan-1 is a transmembrane heparan sulfate proteoglycan which is indispensable in the structural and functional integrity of epithelia. Normal hepatocytes display strong cell surface expression of syndecan-1; however, upon malignant transformation, they may lose it from their cell surfaces. In this study, we demonstrate that re-expression of full-length or ectodomain-deleted syndecan-1 in hepatocellular carcinoma cells downregulates phosphorylation of ERK1/2 and p38, with the truncated form exerting an even stronger effect than the full-length protein. Furthermore, overexpression of syndecan-1 in hepatoma cells is associated with a shift of heparan sulfate structure toward a highly sulfated type specific for normal liver. As a result, cell proliferation and proteolytic shedding of syndecan-1 from the cell surface are restrained, which facilitates redifferentiation of hepatoma cells to a more hepatocyte-like phenotype. Our results highlight the importance of syndecan-1 in the formation and maintenance of differentiated epithelial characteristics in hepatocytes partly via the HGF/ERK/Ets-1 signal transduction pathway. Downregulation of Ets-1 expression alone, however, was not sufficient to replicate the phenotype of syndecan-1 overexpressing cells, indicating the need for additional molecular mechanisms. Accordingly, a reporter gene assay revealed the inhibition of Ets-1 as well as AP-1 transcription factor-induced promoter activation, presumably an effect of the heparan sulfate switch.

    Topics: Carcinoma, Hepatocellular; Cell Differentiation; Cell Proliferation; Gene Expression Regulation, Neoplastic; Hep G2 Cells; Heparitin Sulfate; Hepatocyte Growth Factor; Hepatocytes; Humans; Liver Neoplasms; MAP Kinase Signaling System; Proto-Oncogene Protein c-ets-1; Signal Transduction; Syndecan-1; Transcription Factor AP-1

2020
Heparanase-1-induced shedding of heparan sulfate from syndecan-1 in hepatocarcinoma cell facilitates lymphatic endothelial cell proliferation via VEGF-C/ERK pathway.
    Biochemical and biophysical research communications, 2017, 04-01, Volume: 485, Issue:2

    Heparanase-1/syndecan-1 axis plays critical roles in tumorigenesis and development. The main mechanism includes heparanase-1 (HPA-1) degrades the heparan sulfate chain of syndecan-1 (SDC-1), and the following shedding of heparan sulfate from tumor cell releases and activates SDC-1 sequestered growth factors. However, the significance of Heparanase-1/syndecan-1 axis and its effects on the microenvironment of lymphatic metastasis in hepatocellular carcinogenesis (HCC) procession have not been reported. Herein, we found that HPA-1 could degrade the heparan sulfate on hepatocarcinoma cell surface. Importantly, HPA-1-induced shedding of heparan sulfate chain from SDC-1 facilitated the release of vascular endothelial growth factor C (VEGF-C) from SDC-1/VEGF-C complex into the medium of hepatocarcinoma cell. Further studies indicated that VEGF-C secretion from hepatocarcinoma cell promoted lymphatic endothelial cell growth through activating extracellular signal-regulated kinase (ERK) signaling. Taken together, this study reveals a novel existence of Heparanase-1/syndecan-1 axis in hepatocarcinoma cell and its roles in the cross-talking with the microenvironment of lymphatic metastasis.

    Topics: Animals; Blotting, Western; Carcinoma, Hepatocellular; Cell Line, Tumor; Cell Proliferation; Endothelial Cells; Glucuronidase; Heparitin Sulfate; Liver Neoplasms; Lymphatic Metastasis; Lymphatic Vessels; MAP Kinase Signaling System; Mice; Protein Binding; Reverse Transcriptase Polymerase Chain Reaction; RNA Interference; Syndecan-1; Tumor Microenvironment; Vascular Endothelial Growth Factor C

2017
Evaluating Tumor-Associated Activity of Extracellular Sulfatase by Analyzing Naturally Occurring Substrate in Tumor Microenvironment of Hepatocellular Carcinoma.
    Analytical chemistry, 2016, 12-20, Volume: 88, Issue:24

    The progress of cancer is intimately connected with the activity of the extracellular matrix (ECM) enzymes. To evaluate the promoting effect of these enzymes on tumor development in a pathological biocontext, we propose in this work to analyze their natural substrates in the ECM. This strategy is demonstrated by studying heparan sulfate (HS), the substrate of ECM sulfatase, in the development of hepatocellular carcinoma (HCC). An assay is designed to study the abundance and sulfation of HS and to evaluate the interactions between HS and the growth factors, such as fibroblast growth factor 2 (FGF2). Peptides derived from the amyloid peptide and various growth factors are employed to detect HS and evaluate their affinity toward the growth factors, whereas the ruthenium polypyridyl complex is taken as a photocatalyst to achieve a more sensitive signal readout. Applying this method to HepG2 cells, correlated changes between the activity of sulfatase 2 in regulating FGF2-induced cell proliferation and the abundance, degree of sulfation, and growth factor binding of HS can be observed. This method has also been applied to analyze clinical tissue samples of HCC. The results may suggest tumor-progress-related alterations in the above-studied biochemical features of HS. These results may point to the prospect of using this method to facilitate the diagnosis and prognosis of HCC in the future.

    Topics: Carcinoma, Hepatocellular; Fibroblast Growth Factor 2; Hep G2 Cells; Heparitin Sulfate; Humans; Liver Neoplasms; Models, Molecular; Substrate Specificity; Sulfatases; Sulfotransferases; Tumor Microenvironment

2016
Human Monoclonal Antibody Targeting the Heparan Sulfate Chains of Glypican-3 Inhibits HGF-Mediated Migration and Motility of Hepatocellular Carcinoma Cells.
    PloS one, 2015, Volume: 10, Issue:9

    Heparan sulfate proteoglycans (HSPGs) participate in many processes related to tumor development, including tumorigenesis and metastasis. HSPGs contain one or more heparan sulfate (HS) chains that are covalently linked to a core protein. Glypican-3 (GPC3) is a cell surface-associated HSPG that is highly expressed in hepatocellular carcinoma (HCC). GPC3 is involved in Wnt3a-dependent HCC cell proliferation. Our previous study reported that HS20, a human monoclonal antibody targeting the HS chains on GPC3, inhibited Wnt3a/β-catenin activation. In the current study, we showed that the HS chains of GPC3 could mediate HCC cells' migration and motility. Knocking down GPC3 or targeting the HS chains by HS20 inhibited HCC cell migration and motility. However, HS20 had no effect on GPC3 knockdown cells or GPC3 negative cells. In addition, an antibody that recognizes the core protein of GPC3 did not change the rate of cell motility. HCC cell migration and motility did not respond to either canonical or non-canonical Wnt induction, but did increase under hepatocyte growth factor (HGF) treatment. HS20-treated HCC cells exhibited less ability for HGF-mediated migration and motility. Furthermore, HS20 inhibited in vitro HCC spheroid formation and liver tumor growth in mice. GPC3 interacted with HGF; however, a mutant GPC3 lacking the HS chain showed less interaction with HGF. Blocking the HS chains on GPC3 with HS20 reduced c-Met activation in HGF-treated HCC cells and 3D-cultured spheroids. Taken together, our study suggests that GPC3 is involved in HCC cell migration and motility through HS chain-mediated cooperation with the HGF/Met pathway, showing how HS targeting has potential therapeutic implications for liver cancer.

    Topics: Antibodies, Monoclonal; Carcinoma, Hepatocellular; Cell Line, Tumor; Cell Movement; Glypicans; Heparitin Sulfate; Hepatocyte Growth Factor; Humans; Liver Neoplasms

2015
Inactivation of Wnt signaling by a human antibody that recognizes the heparan sulfate chains of glypican-3 for liver cancer therapy.
    Hepatology (Baltimore, Md.), 2014, Volume: 60, Issue:2

    Wnt signaling is important for cancer pathogenesis and is often up-regulated in hepatocellular carcinoma (HCC). Heparan sulfate proteoglycans (HSPGs) function as coreceptors or modulators of Wnt activation. Glypican-3 (GPC3) is an HSPG that is highly expressed in HCC, where it can attract Wnt proteins to the cell surface and promote cell proliferation. Thus, GPC3 has emerged as a candidate therapeutic target in liver cancer. While monoclonal antibodies to GPC3 are currently being evaluated in preclinical and clinical studies, none have shown an effect on Wnt signaling. Here, we first document the expression of Wnt3a, multiple Wnt receptors, and GPC3 in several HCC cell lines, and demonstrate that GPC3 enhanced the activity of Wnt3a/β-catenin signaling in these cells. Then we report the identification of HS20, a human monoclonal antibody against GPC3, which preferentially recognized the heparan sulfate chains of GPC3, both the sulfated and nonsulfated portions. HS20 disrupted the interaction of Wnt3a and GPC3 and blocked Wnt3a/β-catenin signaling. Moreover, HS20 inhibited Wnt3a-dependent cell proliferation in vitro and HCC xenograft growth in nude mice. In addition, HS20 had no detectable undesired toxicity in mice. Taken together, our results show that a monoclonal antibody primarily targeting the heparin sulfate chains of GPC3 inhibited Wnt/β-catenin signaling in HCC cells and had potent antitumor activity in vivo.. An antibody directed against the heparan sulfate of a proteoglycan shows efficacy in blocking Wnt signaling and HCC growth, suggesting a novel strategy for liver cancer therapy.

    Topics: Animals; Antibodies, Monoclonal; beta Catenin; Carcinoma, Hepatocellular; Cell Surface Display Techniques; Female; Glypicans; Hep G2 Cells; Heparitin Sulfate; Humans; Liver Neoplasms; Mice; Mice, Inbred BALB C; Mice, Nude; Wnt Signaling Pathway; Xenograft Model Antitumor Assays

2014
WNT/β-catenin signaling and hepatocellular carcinoma.
    Hepatology (Baltimore, Md.), 2014, Volume: 60, Issue:2

    Topics: Animals; Antibodies, Monoclonal; Carcinoma, Hepatocellular; Female; Glypicans; Heparitin Sulfate; Humans; Liver Neoplasms; Wnt Signaling Pathway

2014
Granulin-epithelin precursor interacts with heparan sulfate on liver cancer cells.
    Carcinogenesis, 2014, Volume: 35, Issue:11

    Granulin-epithelin precursor (GEP) is a pluripotent secretory growth factor which promotes cancer progression in a number of human cancers. However, how cancer cells interact with GEP remains unknown. In this study, we aimed to identify the cell surface-binding partner of GEP on liver cancer cells. Human recombinant GEP (rGEP) was expressed and purified to homogeneity. The rGEP was shown to trigger phosphorylation of AKT and ERK1/2 in liver cancer cells. We demonstrated cell surface attachment of rGEP, which was blocked by prebinding of platelet-derived growth factor-AA, platelet-derived growth factor-BB and fibroblast growth factor-2. Therefore, heparan sulfate (HS) had been reasoned as the binding partner of rGEP. Heparinase digestion validated the role of HS on supporting the attachment. The heparin-binding domain of GEP was mapped to RRH(555-557) in the C-terminal region. Suppression of the HS polymerase exostosin-1 reduced the rGEP binding and rGEP-mediated signaling transduction. Suppression of a specific HS proteoglycan, glypican-3, also showed a partial reduction of rGEP binding and an inhibition on rGEP-mediated activation of AKT. Furthermore, glypican-3 was shown to correlate with the expressions of GEP in clinical samples (Spearman's ρ = 0.363, P = 0.001). This study identified HS, partly through glypican-3, as a novel binding partner of GEP on the surface of liver cancer cells.

    Topics: Carcinoma, Hepatocellular; Fibroblast Growth Factor 2; Gene Expression Regulation, Neoplastic; Glypicans; Hep G2 Cells; Heparitin Sulfate; Humans; Intercellular Signaling Peptides and Proteins; Liver Neoplasms; MAP Kinase Signaling System; Oncogene Protein v-akt; Progranulins; Protein Binding

2014
Heparin and liver heparan sulfate can rescue hepatoma cells from topotecan action.
    BioMed research international, 2014, Volume: 2014

    Topotecan (TpT) is a major inhibitory compound of topoisomerase (topo) I that plays important roles in gene transcription and cell division. We have previously reported that heparin and heparan sulfate (HS) might be transported to the cell nucleus and they can interact with topoisomerase I. We hypothesized that heparin and HS might interfere with the action of TpT. To test this hypothesis we isolated topoisomerase I containing cell nuclear protein fractions from normal liver, liver cancer tissues, and hepatoma cell lines. The enzymatic activity of these extracts was measured in the presence of heparin, liver HS, and liver cancer HS. In addition, topo I activity, cell viability, and apoptosis of HepG2 and Hep3B cells were investigated after heparin and TpT treatments. Liver cancer HS inhibited topo I activity in vitro. Heparin treatment abrogated topo I enzyme activity in Hep3B cells, but not in HepG2 cells, where the basal activity was higher. Heparin protected the two hepatoma cell lines from TpT actions and decreased the rate of TpT induced S phase block and cell death. These results suggest that heparin and HS might interfere with the function of TpT in liver and liver cancer.

    Topics: Carcinoma, Hepatocellular; Cell Cycle; Cell Proliferation; DNA Topoisomerases, Type I; DNA, Neoplasm; Hep G2 Cells; Heparin; Heparitin Sulfate; Humans; Liver; Liver Neoplasms; Topotecan

2014
Shedding of syndecan-1 from human hepatocytes alters very low density lipoprotein clearance.
    Hepatology (Baltimore, Md.), 2012, Volume: 55, Issue:1

    We recently showed that the heparan sulfate proteoglycan syndecan-1 mediates hepatic clearance of triglyceride-rich lipoproteins in mice based on systemic deletion of syndecan-1 and hepatocyte-specific inactivation of sulfotransferases involved in heparan sulfate biosynthesis. Here, we show that syndecan-1 expressed on primary human hepatocytes and Hep3B human hepatoma cells can mediate binding and uptake of very low density lipoprotein (VLDL). Syndecan-1 also undergoes spontaneous shedding from primary human and murine hepatocytes and Hep3B cells. In human cells, phorbol myristic acid induces syndecan-1 shedding, resulting in accumulation of syndecan-1 ectodomains in the medium. Shedding occurs through a protein kinase C-dependent activation of ADAM17 (a disintegrin and metalloproteinase 17). Phorbol myristic acid stimulation significantly decreases DiD (1,1'-dioctadecyl-3,3,3',3'-tetramethylindodicarbocyanine perchlorate)-VLDL binding to cells, and shed syndecan-1 ectodomains bind to VLDL. Although mouse hepatocytes appear resistant to induced shedding in vitro, injection of lipopolysaccharide into mice results in loss of hepatic syndecan-1, accumulation of ectodomains in the plasma, impaired VLDL catabolism, and hypertriglyceridemia.. These findings suggest that syndecan-1 mediates hepatic VLDL turnover in humans as well as in mice and that shedding might contribute to hypertriglyceridemia in patients with sepsis.

    Topics: Animals; Carcinogens; Cell Line, Tumor; Heparitin Sulfate; Hepatocytes; Humans; Hypertriglyceridemia; Lipopolysaccharides; Lipoproteins, VLDL; Liver Neoplasms; Mice; Mice, Inbred C57BL; Mice, Mutant Strains; Protein Kinase C; Sepsis; Syndecan-1; Tetradecanoylphorbol Acetate; Triglycerides

2012
Effect of heparin, fucoidan and other polysaccharides on adhesion of enterohepatic helicobacter species to murine macrophages.
    Applied biochemistry and biotechnology, 2011, Volume: 164, Issue:1

    Helicobacter species have been isolated and cultured from both the gastric and enterohepatic niches of the gastrointestinal tract and are associated with a wide spectrum of diseases. Some members of the enterohepatic Helicobacter species (EHS), which include Helicobacter bilis, Helicobacter hepaticus and Helicobacter pullorum, are associated with chronic inflammatory and proliferative bowel inflammation, hepatitis and in experimental murine studies with hepatic cancer. The present study aimed to explore if polysulphated polysaccharides can prevent adhesion of EHS to the murine macrophage cell line J774A.1. A competitive binding assay showed that heparin and heparan sulphate at a concentration of 1.25 mg/ml reduced binding of H. hepaticus and H. pullorum to the host cells, but not H. bilis. Of the tested Helicobacter spp, the highest inhibition by heparin was demonstrated for H. pullorum (P < 0.01), the most hydrophilic strain. Partially or completely de-sulphated heparin derivatives lost the ability to inhibit adherence of EHS, indicating the importance of sulphated groups of heparin. The most efficient inhibitor of EHS binding to macrophages was fucoidan, which reduced bacterial adhesion of the three enterohepatic Helicobacter species to a greater extent than heparin, 60-90% inhibition vs 30-70% inhibition by heparin. Identification of receptors that EHS ligands bind to is important for understanding the development of infection and may provide a rational target to prevent infection and therapy.

    Topics: Animals; Bacterial Adhesion; Binding, Competitive; Cell Line; Fluorescein-5-isothiocyanate; Gastrointestinal Tract; Helicobacter; Helicobacter Infections; Heparin; Heparitin Sulfate; Hepatitis; Hydrophobic and Hydrophilic Interactions; Liver Neoplasms; Macrophages; Mice; Microscopy, Fluorescence; Polysaccharides; Structure-Activity Relationship

2011
Mutation of herpesvirus Saimiri ORF51 glycoprotein specifically targets infectivity to hepatocellular carcinoma cell lines.
    Journal of biomedicine & biotechnology, 2011, Volume: 2011

    Herpesvirus saimiri (HVS) is a gamma herpesvirus with several properties that make it an amenable gene therapy vector; namely its large packaging capacity, its ability to persist as a nonintegrated episome, and its ability to infect numerous human cell types. We used RecA-mediated recombination to develop an HVS vector with a mutated virion protein. The heparan sulphate-binding region of HVS ORF51 was substituted for a peptide sequence which interacts with somatostatin receptors (SSTRs), overexpressed on hepatocellular carcinoma (HCC) cells. HVS mORF51 showed reduced infectivity in non-HCC human cell lines compared to wild-type virus. Strikingly, HVS mORF51 retained its ability to infect HCC cell lines efficiently. However, neutralisation assays suggest that HVS mORF51 has no enhanced binding to SSTRs. Therefore, mutation of the ORF51 glycoprotein has specifically targeted HVS to HCC cell lines by reducing the infectivity of other cell types; however, the mechanism for this targeting is unknown.

    Topics: Amino Acid Sequence; Animals; Carcinoma, Hepatocellular; Cell Line, Tumor; Cloning, Molecular; Electrophoresis, Agar Gel; Flow Cytometry; Genetic Vectors; Heparitin Sulfate; Herpesvirus 2, Saimiriine; Humans; Liver Neoplasms; Membrane Glycoproteins; Mice; Molecular Sequence Data; Mutation; Neutralization Tests; Receptors, Somatostatin; Viral Envelope Proteins

2011
Quantitative and qualitative alterations of heparan sulfate in fibrogenic liver diseases and hepatocellular cancer.
    The journal of histochemistry and cytochemistry : official journal of the Histochemistry Society, 2010, Volume: 58, Issue:5

    Heparan sulfate (HS), due to its ability to interact with a multitude of HS-binding factors, is involved in a variety of physiological and pathological processes. Remarkably diverse fine structure of HS, shaped by non-exhaustive enzymatic modifications, influences the interaction of HS with its partners. Here we characterized the HS profile of normal human and rat liver, as well as alterations of HS related to liver fibrogenesis and carcinogenesis, by using sulfation-specific antibodies. The HS immunopattern was compared with the immunolocalization of selected HS proteoglycans. HS samples from normal liver and hepatocellular carcinoma (HCC) were subjected to disaccharide analysis. Expression changes of nine HS-modifying enzymes in human fibrogenic diseases and HCC were measured by quantitative RT-PCR. Increased abundance and altered immunolocalization of HS was paralleled by elevated mRNA levels of HS-modifying enzymes in the diseased liver. The strong immunoreactivity of the normal liver for 3-O-sulfated epitope further increased with disease, along with upregulation of 3-OST-1. Modest 6-O-undersulfation of HCC HS is probably explained by Sulf overexpression. Our results may prompt further investigation of the role of highly 3-O-sulfated and partially 6-O-desulfated HS in pathological processes such as hepatitis virus entry and aberrant growth factor signaling in fibrogenic liver diseases and HCC.

    Topics: Agrin; Animals; Carcinoma, Hepatocellular; Chronic Disease; Disaccharides; Focal Nodular Hyperplasia; Glucuronidase; Glypicans; Heparan Sulfate Proteoglycans; Heparitin Sulfate; Humans; Immunohistochemistry; Liver; Liver Cirrhosis; Liver Neoplasms; Male; Rats; Rats, Wistar; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Sulfotransferases; Syndecan-1

2010
WSS25 inhibits growth of xenografted hepatocellular cancer cells in nude mice by disrupting angiogenesis via blocking bone morphogenetic protein (BMP)/Smad/Id1 signaling.
    The Journal of biological chemistry, 2010, Oct-15, Volume: 285, Issue:42

    The highly expressed Id1 (inhibitor of DNA binding/differentiation) protein promotes angiogenesis in HCC and is a well established target for anti-angiogenesis therapeutic strategies. Heparan sulfate (HS) mimetics such as PI-88 can abrogate HS-protein interactions to inhibit angiogenesis. Id1 is the direct downstream effector of bone morphogenetic proteins (BMPs), which are angiogenic and HS-binding proteins. Thus, targeting BMPs by HS mimetics may inhibit angiogenesis via attenuating Id1 expression. We report here that a HS mimetic WSS25 potently inhibited the tube formation of HMEC-1 cells on Matrigel and their migration. Meanwhile, WSS25 (25 μg/ml) nearly completely blocked Id1 expression in the HMEC-1 cells as demonstrated by oligo-angiogenesis microarray analysis and further confirmed by RT-PCR and Western blotting. BMP/Smad/Id1 signaling also was blocked by WSS25 treatment in HMEC-1 cells. Importantly, Id1 knockdown in HMEC-1 cells caused the disruption of their tube formation on Matrigel. By employing quartz crystal microbalance analysis, we found that WSS25 strongly bound to BMP2. Moreover, WSS25 impaired BMP2-induced tube formation of HMEC-1 cells on Matrigel and angiogenesis in Matrigel transplanted into C57BL6 mice. Furthermore, WSS25 (100 mg/kg) abrogated the growth of HCC cells xenografted in male nude mice. Immunohistochemical analysis showed that both the expression of Id1 and the endothelial cell marker CD31 were lower in the WSS25-treated tumor tissue than in the control. Therefore, WSS25 is a potential drug candidate for HCC therapy as a tumor angiogenesis inhibitor.

    Topics: Animals; Bone Morphogenetic Proteins; Carcinoma, Hepatocellular; Cell Line, Tumor; Glucans; Heparitin Sulfate; Humans; Inhibitor of Differentiation Protein 1; Liver Neoplasms; Male; Mice; Mice, Inbred BALB C; Mice, Inbred C57BL; Mice, Nude; Molecular Structure; Neoplasm Transplantation; Neoplasms, Experimental; Neovascularization, Pathologic; Quartz Crystal Microbalance Techniques; Signal Transduction; Smad Proteins; Transplantation, Heterologous

2010
Glycosaminoglycan mimetics inhibit SDF-1/CXCL12-mediated migration and invasion of human hepatoma cells.
    Glycobiology, 2009, Volume: 19, Issue:12

    We have recently reported that the CXC-chemokine stromal cell-derived factor-1 (SDF-1)/CXCL12 induces proliferation, migration, and invasion of the Huh7 human hepatoma cells through its G-protein-coupled receptor CXCR4 and that glycosaminoglycans (GAGs) are involved in these events. Here, we demonstrate by surface plasmon resonance that the chemokine binds to GAG mimetics obtained by grafting carboxylate, sulfate or acetate groups onto a dextran backbone. We also demonstrate that chemically modified dextrans inhibit SDF-1/CXCL12-mediated in vitro chemotaxis and anchorage-independent cell growth in a dose-dependent manner. The binding of GAG mimetics to the chemokine and their effects in modulating the SDF-1/CXCL12 biological activities are mainly related to the presence of sulfate groups. Furthermore, the mRNA expression of enzymes involved in heparan sulfate biosynthesis, such as exostosin-1 and -2 or N-deacetylase N-sulfotransferases remained unchanged, but heparanase mRNA and protein expressions in Huh7 cells were decreased upon GAG mimetic treatment. Moreover, decreasing heparanase-1 mRNA levels by RNA interference significantly reduced SDF-1/CXCL12-induced extracellular signal-regulated kinase 1/2 (ERK 1/2) phosphorylation. Therefore, we suggest that GAG mimetic effects on SDF-1/CXCL12-mediated hepatoma cell chemotaxis may rely on decreased heparanase expression, which impairs SDF-1/CXCL12's signaling. Altogether, these data suggest that GAG mimetics may compete with cellular heparan sulfate chains for the binding to SDF-1/CXCL12 and may affect heparanase expression, leading to reduced SDF-1/CXCL12 mediated in vitro chemotaxis and growth of hepatoma cells.

    Topics: Binding, Competitive; Carcinoma, Hepatocellular; Cell Adhesion; Cell Communication; Cell Movement; Chemokine CXCL12; Glucuronidase; Glycosaminoglycans; Heparitin Sulfate; Humans; Liver Neoplasms; Neoplasm Invasiveness; RNA, Small Interfering; Tumor Cells, Cultured

2009
Kasabach-Merritt syndrome associated with giant liver hemangioma: the effect of combined therapy with danaparoid sodium and tranexamic acid.
    Haematologica, 2005, Volume: 90 Suppl

    n patients with Kasabach-Merritt syndrome (KMS), local activation of coagulation commonly results in disseminated intravascular coagulation (DIC). Progress of DIC is associated with 30-40% mortality as a result of uncontrollable hemorrhage. A 39-year-old woman with an enlarging giant liver hemangioma was diagnosed as having KMS with DIC. To control the hemorrhagic diathesis, we commenced combination therapy for DIC with danaparoid (1,250 Ux2/day, intravenously (IV)) and tranexamic acid (0.5 g x 3/day, peros (PO). Rapid improvement of the bleeding tendency and coagulopathy occurred in response to this treatment - that is, DIC was controlled without removing the giant hemangioma. The therapy did not restrict the behavior of the patient by continuous drip and angiography could be performed without bleeding. Such therapy may be beneficial in chronic DIC with activation of fibrinolysis.

    Topics: Adult; Antifibrinolytic Agents; Blood Proteins; Chondroitin Sulfates; Dermatan Sulfate; Disseminated Intravascular Coagulation; Drug Therapy, Combination; Female; Hemangioma; Hemorrhagic Disorders; Heparitin Sulfate; Hepatic Artery; Humans; Ligation; Liver Neoplasms; Syndrome; Tranexamic Acid

2005
hSulf1 Sulfatase promotes apoptosis of hepatocellular cancer cells by decreasing heparin-binding growth factor signaling.
    Gastroenterology, 2004, Volume: 126, Issue:1

    The heparin-binding growth factors fibroblast growth factor (FGF) and hepatocyte growth factor (HGF) are potent mitogens for hepatocellular carcinomas (HCCs). Heparin-binding growth factor signaling is regulated by sulfation of cell-surface heparan sulfate proteoglycans (HSPGs). We hypothesized that hSulf1, a recently described sulfatase, regulates growth signaling in HCCs.. Expression of hSulf1 in human HCC tumors was determined by real-time PCR. Down-regulation of hSulf1 expression was investigated by analyzing loss of heterozygosity (LOH) at the hSulf1 locus and the effect of the DNA methylation inhibitor 5-aza-deoxycytidine on hSulf1 expression. The subcellular location of hSulf1 and sulfation state of cell-surface HSPGs were assessed by immunocytochemistry. FGF and HGF signaling was examined by phospho-specific immunoblot analysis. Cell growth was measured by trypan blue exclusion, and the MTT assay and apoptosis were quantitated by fluorescence microscopy.. hSulf1 expression was decreased in 29% of HCCs and 82% of HCC cell lines. There was LOH at the hSulf1 locus in 42% of HCCs. Treatment with 5-aza-deoxycytidine reactivated hSulf1 expression in hSulf1-negative cell lines. Low hSulf1-expressing cells showed increased sulfation of cell-surface HSPGs, enhanced FGF and HGF-mediated signaling, and increased HCC cell growth. Conversely, forced expression of hSulf1 decreased sulfation of cell-surface HSPGs and abrogated growth signaling. HCC cells with high-level hSulf1 expression were sensitive to staurosporine- or cisplatin-induced apoptosis, whereas low expressing cells were resistant. Transfection of hSulf1 into hSulf1-negative cells restored staurosporine and cisplatin sensitivity.. Down-regulation of hSulf1 contributes to hepatocarcinogenesis by enhancing heparin-binding growth factor signaling and resistance to apoptosis.

    Topics: Apoptosis; Carcinoma, Hepatocellular; Cell Division; Cell Line, Tumor; Cell Membrane; Cisplatin; DNA Methylation; Fibroblast Growth Factor 2; Heparitin Sulfate; Hepatocyte Growth Factor; Humans; Liver Neoplasms; Loss of Heterozygosity; Protein Structure, Tertiary; RNA, Messenger; Signal Transduction; Staurosporine; Sulfates; Sulfotransferases

2004
Exploitation of heparanase inhibitors from microbial metabolites using an efficient visual screening system.
    The Journal of antibiotics, 2004, Volume: 57, Issue:2

    In this paper we describe the establishment of an efficient visual method for screening heparanase inhibitors, and we present the results of screening 10,000 microbial culture broths. Heparanase-overexpressing stable clones of the human hepatocellular carcinoma HepG2 cells were established and used as an enzyme source. Digestion of heparan sulfate (HS) was detected using novel HS-containing tablets or SDS-polyacrylamide gel electrophoresis. This method was able to find suramin, a known heparanase inhibitor, from a library of typical enzyme inhibitors. By screening 10,000 culture broths of microorganisms (actinomycetes, fungi, and bacteria) an actinomycete strain, RK99-A234, was found to have heparanase inhibitory activity. RK-682 was identified in the fermentation broth as a heparanase inhibitor, IC50 = 17 microM.

    Topics: Actinobacteria; Animals; Blotting, Western; Carcinoma, Hepatocellular; Cell Line, Tumor; Clone Cells; Culture Media; DNA, Complementary; Drug Evaluation, Preclinical; Electrophoresis, Polyacrylamide Gel; Enzyme Inhibitors; Glucuronidase; Heparitin Sulfate; Humans; Liver Neoplasms; Phosphoprotein Phosphatases; Transfection

2004
Expression of the CD44v2-10 isoform confers a metastatic phenotype: importance of the heparan sulfate attachment site CD44v3.
    Cancer research, 2003, Feb-15, Volume: 63, Issue:4

    We expressed the full-length CD44v2-10 isoform in SKHep1 cells, a nonmetastatic human hepatocellular carcinoma cell line that does not express any endogenous CD44v isoforms. In SCID mice, expression of CD44v2-10 by SKHep1 cells had no effect on s.c. primary tumor development but caused pulmonary metastases in 41% (7 of 17) of animals compared with control SKHep1 cells (0 of 16; P < 0.01). CD44v2-10 expression by SKHep1 cells resulted in enhanced heparan sulfate (HS) attachment and an enhanced capacity to bind heparin-binding growth factors. Mutation of the v3 domain to prevent HS attachment and growth factor binding abolished the metastatic phenotype, demonstrating that HS modification of CD44v2-10 plays a critical role in the development of metastases in this model. However, in vitro proliferation, motility, and invasion were not altered by CD44v2-10 expression.

    Topics: Alternative Splicing; Binding Sites; Carcinoma, Hepatocellular; Cell Adhesion; Cell Division; Cell Movement; Growth Substances; Heparitin Sulfate; Humans; Hyaluronan Receptors; Hyaluronic Acid; Liver Neoplasms; Lung Neoplasms; Neoplasm Metastasis; Protein Isoforms; Tumor Cells, Cultured

2003
Effect of heparin and liver heparan sulphate on interaction of HepG2-derived transcription factors and their cis-acting elements: altered potential of hepatocellular carcinoma heparan sulphate.
    The Biochemical journal, 2000, Aug-15, Volume: 350 Pt 1

    Proteoglycan assembly in malignant tumours is subject to profound changes. The significance of these alterations is not well understood; especially, their role in nuclear regulation is a topic for debate. The capacity of heparin and liver carcinoma heparan sulphate (HS) to alter DNA-transcription factor interactions has been studied to provide further evidence concerning the regulatory potential of glycosaminoglycan (GAG) in the nucleus. Experiments both in vitro and in vivo indicated that heparin and HS are capable of inhibiting the interaction of transcription factors with their consensus oligonucleotide elements. Among five transcription factors studied, AP-1, SP-1, ETS-1 and nuclear factor kappaB proved to be sensitive to heparin and heparan sulphate, whereas TFIID was hardly inhibited in either in vitro or in vivo systems. Interestingly, HS from peritumoral liver was five times more effective than heparin. Liver carcinoma HS was less effective than liver HS, but its activity was comparable with that of heparin. These results indicate that the structural differences of GAG chains strongly influence their biological behaviour. The loss of their recognized functional activity in malignant tumours might promote the development of uncontrolled growth and gene expression favouring the neoplastic process.

    Topics: Carcinoma, Hepatocellular; DNA-Binding Proteins; Heparin; Heparitin Sulfate; Humans; Liver; Liver Neoplasms; Protein Binding; Transcription Factors; Tumor Cells, Cultured

2000
Substrate specificity of heparanases from human hepatoma and platelets.
    The Journal of biological chemistry, 1998, Jul-24, Volume: 273, Issue:30

    Heparan sulfate proteoglycans, attached to cell surfaces or in the extracellular matrix, interact with a multitude of proteins via their heparan sulfate side chains. Degradation of these chains by limited (endoglycosidic) heparanase cleavage is believed to affect a variety of biological processes. Although the occurrence of heparanase activity in mammalian tissues has been recognized for many years, the molecular characteristics and substrate recognition properties of the enzyme(s) have remained elusive. In the present study, the substrate specificity and cleavage site of heparanase from human hepatoma and platelets were investigated. Both enzyme preparations were found to cleave the single beta-D-glucuronidic linkage of a heparin octasaccharide. A capsular polysaccharide from Escherichia coli K5, with the same (-GlcUAbeta1,4-GlcNAcalpha1,4-)n structure as the unmodified backbone of heparan sulfate, resisted heparanase degradation in its native state as well as after chemical N-deacetylation/N-sulfation or partial enzymatic C-5 epimerization of beta-D-GlcUA to alpha-L-IdceA. By contrast, a chemically O-sulfated (but still N-acetylated) K5 derivative was susceptible to heparanase cleavage. O-Sulfate groups, but not N-sulfate or IdceA residues, thus are essential for substrate recognition by the heparanase(s). In particular, selective O-desulfation of the heparin octasaccharide implicated a 2-O-sulfate group on a hexuronic acid residue located two monosaccharide units from the cleavage site, toward the reducing end.

    Topics: Animals; Antithrombin III; Blood Platelets; Carbohydrate Sequence; Carcinoma, Hepatocellular; Escherichia coli; Glucuronidase; Glycoside Hydrolases; Heparin; Heparitin Sulfate; Humans; Isoenzymes; Liver Neoplasms; Mast-Cell Sarcoma; Mice; Microsomes; Molecular Sequence Data; Substrate Specificity; Tumor Cells, Cultured

1998
Heparan sulphate proteoglycan expression in human primary liver tumours.
    The Journal of pathology, 1998, Volume: 185, Issue:3

    Heparan sulphate proteoglycans (HSPGs) play important biological roles in cell-matrix adhesion processes and are essential regulators of growth factor actions (e.g., as co-receptor for hepatocyte growth factor). Since in liver carcinogenesis, interactions between cells, the matrix, and growth factors play a major role, the aim of this study was to investigate whether the distribution pattern of HSPGs is altered in human primary liver tumours. Twenty-two primary liver tumours and five normal liver biopsies were studied, using specific monoclonal antibodies against syndecans-1, -2, -3, and -4; glypican; perlecan; and heparan sulphate chains. Cholangiocarcinomas as well as hepatocellular carcinomas showed an altered immunoreactivity pattern of the different HSPGs in comparison with normal liver parenchyma, probably reflecting the growth regulatory roles of HSPGs. Intracellular positivity for integral membrane HSPGs syndecan-1 and especially syndecan-4 was a constant finding in most tumours, suggesting increased synthesis or internalization of these HSPGs. Syndecan-3 and perlecan expression in tumours was found in an expected distribution pattern. The strong reactivity for syndecan-3 and perlecan in tumoral stromal vessels might suggest a role for these HSPGs in tumoral angiogenesis. In addition, perlecan probably exerts its known growth factor reservoir function also in the stroma of primary liver tumours.

    Topics: Bile Duct Neoplasms; Bile Ducts, Intrahepatic; Carcinoma, Hepatocellular; Cholangiocarcinoma; Heparan Sulfate Proteoglycans; Heparitin Sulfate; Humans; Immunohistochemistry; Liver; Liver Neoplasms; Membrane Glycoproteins; Microscopy, Immunoelectron; Proteoglycans; Retrospective Studies; Syndecan-1; Syndecans

1998
Role of sinusoidal heparan sulfate proteoglycan in liver metastasis formation.
    International journal of cancer, 1997, May-29, Volume: 71, Issue:5

    Previous studies have indicated that the predominant sites of tumor cell extravasation in the liver are the sinusoidal vessels, where tumor cells contact the sinusoidal endothelium and the subendothelial extracellular matrix containing the basic components of the basement membrane. We studied the role of sinusoidal extracellular matrix in metastatsis formation by 3LL-HH murine tumor cells selected for their preferential liver colonization. 3LL-HH tumor cells did not efficiently adhere to cryosections of the liver, but they recognized the sinusoids and vessel walls. Pre-treatment of the mice with polyclonal anti-basement membrane antibodies [anti-laminin, anti-fibronectin and anti-heparan sulfate proteoglycan (HSPG)] significantly modulated the organ distribution of tumor cell colonies following intracardial injection: all 3 antibodies inhibited kidney colonization; anti-laminin and anti-fibronectin antibodies inhibited lung colonization; and only anti-HSPG antibody inhibited liver colonization. In several organs such as the heart, stomach, pancreas and bladder, anti-basement membrane antibody treatment did not alter the process of colonization. Immunofluorescence studies showed that anti-HSPG antibody recognized the basement membranes of sinusoids and blood vessels. Our data suggest a specific involvement of sinusoidal HSPG in the liver colonization of 3LL-HH cells.

    Topics: Animals; Basement Membrane; Cell Division; Endothelium, Vascular; Extracellular Matrix; Fibronectins; Fluorescent Antibody Technique; Heparan Sulfate Proteoglycans; Heparin; Heparitin Sulfate; Immunization, Passive; Laminin; Liver Neoplasms; Mice; Mice, Inbred C57BL; Neoplasm Transplantation; Proteoglycans; Tumor Cells, Cultured

1997
Protein kinase C bound to the Golgi apparatus supports the formation of constitutive transport vesicles.
    The Biochemical journal, 1996, Dec-01, Volume: 320 ( Pt 2)

    Constitutive secretion of heparan sulphate proteoglycans (HSPGs) was stimulated in human hepatoma HepG2 cells by phorbol 12-myristate 13-acetate (PMA) and inhibited by calphostin C, a specific inhibitor of protein kinase C (PKC). To delineate more closely the site of PKC action, the packaging in vitro of 35SO4-labelled HSPGs into transport vesicles was investigated. Formation of transport vesicles at the trans-Golgi network was stimulated by PMA and inhibited by calphostin C or Ro 31-8220 by using a post-nuclear supernatant. Treatment of either isolated Golgi-enriched membranes or cytosolic proteins with calphostin C provided evidence that membrane-bound PKC forms strongly supported vesicle formation, whereas cytosolic PKC forms showed a marginal effect. The PKC isoforms PKC-alpha and PKC-zeta were attached to highly purified Golgi membranes, as shown by Western blotting. Both isoforms were localized by confocal immunofluorescence microscopy in the Golgi area of HepG2 cells. Immunoelectron microscopy of ultrathin cryosections of HepG2 cells showed that PKC-zeta predominantly attaches to the trans-Golgi region, whereas PKC-alpha binds to the cis- and trans-Golgi area.

    Topics: Carcinoma, Hepatocellular; Cell Fractionation; Cell Line; Cell-Free System; Cytoplasmic Granules; Egtazic Acid; Enzyme Inhibitors; Golgi Apparatus; Heparan Sulfate Proteoglycans; Heparitin Sulfate; Humans; Indoles; Intracellular Membranes; Isoenzymes; Kinetics; Liver Neoplasms; Naphthalenes; Protein Binding; Protein Kinase C; Protein Kinase C-alpha; Proteoglycans

1996
Modulation of heparan-sulphate/chondroitin-sulphate ratio by glycosaminoglycan biosynthesis inhibitors affects liver metastatic potential of tumor cells.
    International journal of cancer, 1995, Sep-15, Volume: 62, Issue:6

    Previous data have indicated that the proteoglycan (PG) pattern is different on tumor cells with different liver metastatic potential. We selected "conventional" glycosaminoglycan (GAG) biosynthesis inhibitors, beta-D-xyloside (BX), 2-deoxy-D-glucose (2-DG), ethane-l-hydroxy-l,l-diphosphonate (ETDP) and the newly discovered 5-hexyl-2-deoxyuridine (HUdR), to modulate PGs on highly metastatic/liver-specific 3LL-HH murine carcinoma and HT168 human melanoma cells and to influence their liver colonization potential. These compounds all induced remarkable changes in GAG biosynthesis, but to varying degrees: glucosamine labelling was affected mainly by 2-DG, and HUdR and sulphation by BX and HUdR. Furthermore, the ratio of heparan sulphate/chondroitin sulphate (HS/CS) of PGs was increased by ETDP and decreased after treatment by HUdR. In addition to changes in PG metabolism, tumor-cell proliferation and adhesion to fibronectin were affected; BX and 2-DG stimulated cell proliferation and adhesion, while HUdR inhibited both proliferation and adhesion. Most interestingly, HUdR, the most effective inhibitor of HS/HSPG, depressed the formation of liver colonies, while ETDP, the most effective inhibitor of CS/CSPG, stimulated the appearance of liver colonies. These observations indicated that, at least in these experimental systems, tumor cells with a high HS/CS ratio are more likely to form liver metastases; consequently, anti-HS agents could also be anti-metastatic.

    Topics: Animals; Antimetabolites; Antimetabolites, Antineoplastic; Chondroitin Sulfates; Deoxyglucose; Deoxyuridine; Etidronic Acid; Glycosaminoglycans; Glycosides; Heparitin Sulfate; Humans; Liver Neoplasms; Melanoma; Mice; Tumor Cells, Cultured

1995
Secretion-capture role for apolipoprotein E in remnant lipoprotein metabolism involving cell surface heparan sulfate proteoglycans.
    The Journal of biological chemistry, 1994, Jan-28, Volume: 269, Issue:4

    To determine the impact of enhanced apolipoprotein (apo) E secretion on the mechanism of remnant lipoprotein uptake, rat hepatoma cells (McA-RH7777) were stably transfected with normal human apoE3 or receptor binding-defective apoE-Leiden. After a 2-h incubation, the human apoE secreted from the transfected hepatocytes was 10-12 times greater than the endogenous rat apoE. The apoE3-transfected cells bound and internalized rabbit beta-very low density lipoproteins (beta-VLDL) to a much greater degree than did apoE-Leiden-transfected cells and nontransfected cells. The apoE3-secreting cells displayed a 2-3.5-fold enhancement of cell-associated beta-VLDL compared to either the apoE-Leiden-transfected or nontransfected cells. Fluorescently labeled beta-VLDL were observed to concentrate within intracellular granules of the apoE3-transfected cells, presumably within endosomes and lysosomes. Furthermore, electron microscopy revealed that the apoE3-secreting cells displayed abundant beta-VLDL and chylomicron remnants on their cell surfaces and microvilli, in contrast to non-transfected or apoE-Leiden-secreting cells. Electron microscopy also revealed an abundance of chylomicron remnants within intracellular vesicles and multivesicular bodies of apoE3-transfected hepatocytes. Heparinase treatment (3 units/ml) completely abolished the increased association of beta-VLDL with apoE3-transfected cells but did not affect the limited association of beta-VLDL with apoE-Leiden-transfected or nontransfected cells. We established that the apoE3-enriched beta-VLDL were bound to cell surface heparan sulfate proteoglycans, as was the newly synthesized and secreted apoE3 (approximately 12% of the total secreted apoE3 was released by heparinase and suramin; 4% by heparin). In addition, reisolation of beta-VLDL by fast performance liquid chromatography after their incubation with exogenous apoE3, with medium from apoE3-secreting cells, or with the apoE3-secreting cells themselves revealed that the particles were enriched in apoE3 and displayed enhanced binding. These results suggest a secretion-capture role for apoE and indicate an important role for heparan sulfate proteoglycans on the cell surface for remnant lipoprotein metabolism.

    Topics: Animals; Apolipoprotein E3; Apolipoproteins E; Biological Transport; Cell Line; Cell Membrane; Heparan Sulfate Proteoglycans; Heparitin Sulfate; Humans; Kinetics; Lipoproteins, VLDL; Liver Neoplasms; Liver Neoplasms, Experimental; Low Density Lipoprotein Receptor-Related Protein-1; Microscopy, Electron; Models, Biological; Models, Structural; Proteoglycans; Rabbits; Rats; Receptors, Lipoprotein; Transfection; Tumor Cells, Cultured

1994
Role of heparan sulfate proteoglycans in the binding and uptake of apolipoprotein E-enriched remnant lipoproteins by cultured cells.
    The Journal of biological chemistry, 1993, May-15, Volume: 268, Issue:14

    Addition of apolipoprotein (apo) E to rabbit beta-very low density lipoproteins (beta-VLDL) has been shown to result in a marked enhancement of their binding and uptake by various cell types. Apolipoprotein E binds to lipoprotein receptors and proteoglycans. To distinguish between apoE binding to these sites, cells were treated with heparinase. Heparinase treatment of receptor-negative familial hypercholesterolemic (FH) fibroblasts and human hepatoma cells (HepG2) released 30-40% of newly synthesized cell surface 35S-labeled proteoglycans and decreased the binding of beta-VLDL+apoE to FH and normal fibroblasts and HepG2 cells by more than 80%. Furthermore, heparinase treatment significantly decreased the uptake of fluorescently labeled beta-VLDL+apoE by HepG2 cells and decreased cholesteryl ester synthesis in FH fibroblasts by 75%. Likewise, canine chylomicron remnants enriched in apoE demonstrated enhanced binding that was 80% inhibited by heparinase treatment of HepG2 cells. Heparinase treatment did not affect beta-VLDL (without added apoE) or low density lipoprotein (LDL) binding to these cells or the binding activity of beta-VLDL+apoE to the LDL receptor-related protein (LRP) or to the LDL receptor on ligand blots. Chinese hamster ovary (CHO) mutant cells lacking the synthesis of either heparan sulfate (pgsD-677) or all proteoglycans (pgsA-745) did not display any enhanced binding of the beta-VLDL+apoE. By comparison, wild-type CHO cells demonstrated enhanced binding of beta-VLDL+apoE that could be abolished by treatment with heparinase. These mutant cells and wild-type CHO cells possessed a similar amount of LRP, as determined by ligand blot analyses and by alpha 2-macroglobulin binding, and possessed a similar amount of LDL receptor activity, as determined by LDL binding. Therefore, we would interpret these data as showing that heparan sulfate proteoglycan may be involved in the initial binding of the apoE-enriched remnants with the subsequent involvement of the LRP in the uptake of these lipoproteins. It remains to be determined whether the heparan sulfate proteoglycan can function by itself in both the binding and internalization of the apoE-enriched remnants or whether the proteoglycan is part of a complex with LRP that mediates a two-step process, i.e. binding and subsequent internalization by the receptor.

    Topics: alpha-Macroglobulins; Animals; Apolipoproteins E; Biological Transport; Carcinoma, Hepatocellular; Cell Membrane; Cells, Cultured; CHO Cells; Cholesterol; Cholesterol Esters; Cricetinae; Diet, Atherogenic; Fibroblasts; Heparan Sulfate Proteoglycans; Heparin Lyase; Heparitin Sulfate; Humans; Hyperlipoproteinemia Type II; Lipoproteins, LDL; Lipoproteins, VLDL; Liver; Liver Neoplasms; Membrane Proteins; Polysaccharide-Lyases; Protein Binding; Proteoglycans; Rabbits; Rats; Receptors, LDL; Transfection; Tumor Cells, Cultured

1993
Potential markers (enzymes, proteoglycans) for human liver tumors.
    Acta bio-medica de L'Ateneo parmense : organo della Societa di medicina e scienze naturali di Parma, 1993, Volume: 64, Issue:5-6

    In the present work the activities of GGT and G-6-Pase and the content of Cyt P-450 were determined in surgically removed liver specimens (16 hepatocellular carcinomas, 8 focal nodular hyperplasias and 4 adenomas). The activities were compared to the surrounding seemingly normal liver tissue. In the adenomas neither of the enzymes studied showed alterations, characteristic for hepatocarcinogenesis. Four out of 8 FNHs had the enzyme pattern that was found in experimental liver carcinogenesis. Liver carcinoma specimens proved to be heterogenous. Neither elevated GGT nor reduced G-6-Pase activity was consistent in these samples although the average of G-6-Pase activity decreased to 50 percent. Cytochrome P-450 was significantly reduced in the majority of cases, showing the best agreement with the tendency observed in experimental models. As an other approach, the qualitative and quantitative alterations of proteoglycans (PG) were analized in the same tumor samples. The amount of sugar components of PGs the glycosaminoglycans (GAG) increased by many times in liver tumors. Carcinoma samples were characterized by about twentyfold increase in chondroitin sulfate content, compared to normal liver. The enhancement of GAGs is partly the consequence of a selective alteration in PG expression. The amount of perlecan and decorin was found to be increased, while syndecan disappeared from liver carcinomas. These data suggest that malignant transformation in liver is accompanied by specific alteration in the content, composition and structure of PGs. Presumably, these changes have significance in tumor progression and have also the potential to be used as markers for liver tumors.

    Topics: Adenoma; Biomarkers, Tumor; Carcinoma, Hepatocellular; Clinical Enzyme Tests; Cytochrome P-450 Enzyme System; Diagnosis, Differential; gamma-Glutamyltransferase; Glucose-6-Phosphatase; Glycosaminoglycans; Heparan Sulfate Proteoglycans; Heparitin Sulfate; Humans; Hyperplasia; Liver; Liver Neoplasms; Membrane Glycoproteins; Proteoglycans; Syndecans

1993
Low density lipoprotein receptor internalizes low density and very low density lipoproteins that are bound to heparan sulfate proteoglycans via lipoprotein lipase.
    The Journal of biological chemistry, 1993, May-05, Volume: 268, Issue:13

    It has previously been shown that lipoprotein lipase (LPL) enhances the binding of low density lipoproteins (LDL) and very low density lipoproteins (VLDL) to HepG2 cells and fibroblasts, up to 80-fold. This increase in binding is LDL receptor-independent and is due to a bridging of LPL between extracellular heparan sulfate proteoglycans (HSPG) and the lipoproteins. In the present paper, we show that preincubation of the cells with LPL, followed by washing prior to the binding experiment, increased binding to the same extent as occurs when the binding is performed in the presence of LPL. This indicates that the formation of a complex of LPL with the lipoproteins is not a prerequisite of binding. Binding curves and Scatchard analyses reveal that both the number of binding sites and the affinity of the binding are increased 20-30-fold by the addition of 3.4 micrograms/ml LPL. The addition of LPL also resulted in an enhanced uptake and subsequent lysosomal degradation of both LDL and VLDL when compared with binding, although to a lesser extent (up to 25-fold when measured after 5 h at 37 degrees C). Strikingly, enhanced uptake did not occur in LDL receptor-negative fibroblasts. In addition, down-regulation of the LDL receptor activity by preincubation of the cells for 48 h with either LDL or beta-VLDL resulted in a parallel decrease in the uptake of LPL-mediated HSPG-bound LDL, whereas the LPL-mediated binding itself was not diminished. These observations indicate that the uptake of LPL-mediated HSPG-bound LDL and VLDL mainly proceeds via the LDL receptor. Binding of labeled LDL to the cells at 4 degrees C for 2 h followed by a chase period at 37 degrees C revealed that in absolute terms, the initial rate of internalization of HSPG-bound LDL is comparable with that of LDL receptor-bound LDL (0.58 and 0.44 ng/min/mg of cell protein, respectively). We conclude that in LDL receptor-positive cells, the LPL-mediated binding of LDL and VLDL to HSPG is followed by internalization of the lipoproteins mainly through the rapid process of the classical LDL receptor recycling system, whereas only a minor portion is internalized via the much slower process of HSPG uptake.

    Topics: Animals; Biological Transport; Carcinoma, Hepatocellular; Cattle; Female; Fibroblasts; Heparan Sulfate Proteoglycans; Heparin Lyase; Heparitin Sulfate; Humans; Kinetics; Lipoprotein Lipase; Lipoproteins, LDL; Lipoproteins, VLDL; Liver Neoplasms; Milk; Models, Biological; Polysaccharide-Lyases; Protein Binding; Proteoglycans; Receptors, LDL; Tumor Cells, Cultured

1993
Heparin and hormonal regulation of mRNA synthesis and abundance of autocrine growth factors: relevance to clonal growth of tumors.
    Molecular and cellular biology, 1991, Volume: 11, Issue:1

    Highly sulfated, heparinlike species of heparan sulfate proteoglycans, with heparinlike glycosaminoglycan chains, are extracellular matrix components that are plasma membrane bound in growth-arrested liver cells. Heparins were found to inhibit the growth and lower the clonal growth efficiency of HepG2, a minimally deviant, human hepatoma cell line. Heparan sulfates, closely related glycosaminoglycans present in the extracellular matrix around growing liver cells, had no effect on the growth rate or clonal growth efficiency of HepG2 cells. Neither heparins nor heparan sulfates had any effect on the growth rate or clonal growth efficiency of two poorly differentiated, highly metastatic hepatoma cell lines, SK-Hep-1 and PLC/PRF/5. Heparin's inhibition of growth of HepG2 cells correlated with changes in the mRNA synthesis and abundance of insulinlike growth factor II (IGF II) and transforming growth factor beta (TGF beta). HepG2 cells expressed high basal levels of mRNAs encoding IGF II and TGF beta that were inducible, through transcriptional and posttranscriptional mechanisms, to higher levels by specific heparin-hormone combinations. For both IGF II and TGF beta, the regulation was multifactorial. Transcriptionally, IGF II was regulated by the additive effects of insulin, glucagon, and growth hormone in combination with heparin; TGF beta was regulated primarily by the synergistic effects of insulin and growth hormone in combination with heparin. Posttranscriptionally, the mRNA abundance of the IGF II 4.5- and 3.7-kb transcripts was affected by insulin. Heparin induction of all IGF II transcripts was also dependent on triiodotyronine and prolactin, but it is unknown whether their induction by heparin was via transcriptional or posttranscriptional mechanisms. Heparin-insulin combinations regulated TGF beta posttranscriptionally. The poorly differentiated hepatoma cell lines PLC/PRF/5 and SK-Hep-1 either did not express or constitutively expressed low basal levels of IGF I, IGF II, and TGF beta, whose mRNA synthesis and abundance showed no response to any heparin-hormone combination. We discuss the data as evidence that matrix chemistry is a variable determining the expression of autocrine growth factor genes and the biological responses to them.

    Topics: Blotting, Northern; Carcinoma, Hepatocellular; Cell Differentiation; Cell Division; Clone Cells; Growth Substances; Heparin; Heparitin Sulfate; Hormones; Humans; In Vitro Techniques; Insulin-Like Growth Factor II; Liver Neoplasms; Neoplasm Metastasis; RNA, Messenger; RNA, Neoplasm; Transforming Growth Factor beta; Tumor Cells, Cultured

1991
Differential basement membrane composition in multiple epithelioid haemangioendotheliomas of liver and lung.
    Histopathology, 1991, Volume: 18, Issue:4

    We report a case of epithelioid haemangioendothelioma involving both lung and liver. The tumour cells were positive for factor-VIII-related antigen. Immunohistochemical analysis of various basement membrane components in tumour tissue of lung and liver showed striking differences. In the liver tumour there was selective expression of collagen IV, with minimal and focal amounts of laminin and basement membrane-associated heparan sulphate proteoglycan. In the lung tumour nodules, in contrast, all these basement membrane components were present. These patterns of basement membrane expression closely resemble those of normal liver and lung basement membrane respectively. We suggest that this provides evidence that epithelioid haemangioendothelioma arises from local endothelial cell proliferation and that it supports the assumption of a multicentric rather than metastatic origin when multiple tumour deposits are found.

    Topics: Aged; Basement Membrane; Chondroitin Sulfate Proteoglycans; Collagen; Female; Hemangioendothelioma; Heparan Sulfate Proteoglycans; Heparitin Sulfate; Humans; Immunohistochemistry; Liver Neoplasms; Lung Neoplasms; Membrane Glycoproteins; Neoplasms, Multiple Primary; von Willebrand Factor

1991
Lewis lung carcinoma variants with differing metastatic specificities adhere preferentially to different defined extracellular matrix molecules.
    Invasion & metastasis, 1988, Volume: 8, Issue:2

    Differential cell adhesion has been proposed to play a role in organ-specific tumor metastasis. To further explore this hypothesis, we have employed a Lewis lung carcinoma cell line and 2 variants that differ in their ability to metastasize to lung and liver. The three cell lines were tested for their ability to adhere to defined extracellular matrix components that had been previously adsorbed to nylon membranes. Our results demonstrate that the parental cell line adheres preferentially to fibronectin relative to all other adhesion molecules tested. The lung colonizing variant, M27, adheres well to fibronectin and also to type V collagen but adheres poorly to laminin, to types I and VI collagen or to heparan sulfate. In contrast, the liver colonizing H59 cell line was highly adherent to laminin as well as to fibronectin but did not adhere to heparan sulfate or to any of the collagen types tested. These results demonstrate that three related cell lines with differing metastatic specificities have marked differences in their abilities to bind to defined matrix molecules. Such differences may play a role in the preferential localization to specific organ beds in vivo.

    Topics: Animals; Carcinoma; Cell Adhesion; Collagen; Extracellular Matrix; Fibronectins; Heparitin Sulfate; Kinetics; Laminin; Liver Neoplasms; Lung Neoplasms; Mice; Neoplasm Metastasis

1988
Changes in charge density of heparan sulfate isolated from cancerous human liver tissue.
    Cancer research, 1981, Volume: 41, Issue:1

    Heparan sulfate fractions were isolated from three normal human livers and three cancerous human liver tissues, and their polyanionic properties were examined using electrophoresis, sequential partition fractionation, and chemical analyses. More than 60% of total glycosaminoglycans from normal human liver and about 30% from cancerous liver tissue were found to be heparan sulfate from their resistance to exhaustive digestion with chondroitinase ABC and their susceptibility to nitrous acid treatment. The heparan sulfate isolated from cancerous liver tissue afforded a lower sulfate/uronic acid molar ratio (0.58 to 0.65) than did normal human liver heparan sulfate (0.76 to 0.80). Also, the former showed lower electrophoretic mobility in 0.1 M HCl and a different partition fractionation profile in comparison with the latter. These differences in charge density of the macromolecule were not detected on the chondroitin sulfate and/or dermatan sulfate fractions isolated from normal human liver and cancerous liver tissue.

    Topics: Chemical Fractionation; Electrophoresis, Cellulose Acetate; Glycosaminoglycans; Heparitin Sulfate; Humans; Liver; Liver Neoplasms; Nitrous Acid

1981
Biochemical composition and heterogeneity of heparan sulfates isolated from AH-130 ascites hepatoma cells and fluid.
    Biochimica et biophysica acta, 1978, Feb-01, Volume: 538, Issue:3

    The glycosaminoglycan composition of AH-130 ascites hepatoma cells and fluid were examined using enzymatic digestion, electrophoresis, and sequential partition fractionation. The cell-associated glycosaminoglycans were found to consist of 93% heparan sulfate, with the remainder consisting primarily of chondroitin sulfate. The glycosaminoglycans isolated from the ascitic fluid were found to consist of 58% heparan sulfate, 26% hyaluronic acid and 16% chondroitin sulfate. Dermatan sulfate was not detected in either cells or fluid. The heparan sulfate isolated from AH-130 cells in low-sulfate and highly heterogeneous with respect to biochemical composition. Fractions isolated by partition fractionation varied from 0.14 mol sulfate/mol uronic acid to 0.6 mol sulfate/mol uronic acid. Of the total sulfate 70--80% is N-sulfate in the former and 50% in the latter. Electrophoresis in 0.1 M HCl showed a highly heterogeneous material with mobility between that of hyaluronic acid and beef lung heparan sulfate. The heparan sulfate isolated from the fluid was similar to that isolated from the cells but was, however, somewhat more homogeneous with respect to charge.

    Topics: Animals; Ascitic Fluid; Carcinoma, Hepatocellular; Cattle; Glycosaminoglycans; Heparitin Sulfate; Hexosamines; Liver; Liver Neoplasms; Lung; Male; Rats; Sulfates; Uronic Acids

1978
Release of glycopeptides and mucopolysaccharides from ascites hepatoma cells by tryptic treatment.
    Journal of biochemistry, 1978, Volume: 83, Issue:1

    Two types of ascites hepatoma cells, AH 66 and AH 130 FN, were treated with trypsin to observe the release of complex carbohydrates constituting the plasma membranes. From AH 66 cells, mucopolysaccharide (heparan sulfate) was preferentially released. From AH 130 FN cells, N-glycosidic glycopeptides were preferentially released whereas no mucopolysaccharide (chondroitin sulfate A) was released.

    Topics: Animals; Carcinoma, Hepatocellular; Cells, Cultured; Female; Glucosamine; Glycopeptides; Glycosaminoglycans; Heparitin Sulfate; Liver Neoplasms; Rats; Sulfates; Trypsin

1978
Urinary glycosaminoglycan patterns in angiosarcoma of the liver.
    Cancer, 1977, Volume: 40, Issue:6

    Glycosaminoglycans extracted from 24-hour urine specimens from patients with hepatic angiosarcoma and from normal/controls were separated as cetylpyridinium complexes into "hyaluronic acid," "chondroitin sulfate," and "heparin" fractions, then further separated and characterized by anion-exchange chromatography and hyaluronidase susceptibility. The chromatographic pattern of the urinary chondroitin sulfate fraction in patients with angiosarcoma of the liver differed from those of controls in that there was a relative increase in the total amount of uronic acid in a hyaluronidase-resistant fraction and a decrease in a fraction susceptible to hyaluronidase digestion. These changes appeared to become more pronounced with advancing disease. Chromatographic patterns and determinations of hyaluronidase susceptibility indicated that the resistant fraction was heparan sulfate and that the susceptible fraction was chondroitin-4-sulfate and/or chondroitin-6-sulfate.

    Topics: Chondroitin Sulfates; Glycosaminoglycans; Hemangiosarcoma; Heparin; Heparitin Sulfate; Humans; Hyaluronic Acid; Hyaluronoglucosaminidase; Liver Neoplasms; Male; Middle Aged

1977
35S incorporation into sulfated mucopolysaccharides from embryonic, normal, and neoplastic liver cells.
    Zeitschrift fur Krebsforschung und klinische Onkologie. Cancer research and clinical oncology, 1976, Jan-02, Volume: 85, Issue:1

    The incorporation of 35S into the sulfated mucopolysaccharides from hepatoma, normal and embryonic liver cells has been studied by means of anion exchange chromatography of the isolated mucopolysaccharide. Comparatively to liver cells, while showing a higher labeling of low sulfated mucopolysaccharides the hepatoma cells incorporate much less 35S into the heparin fraction.

    Topics: Animals; Ascitic Fluid; Carcinoma, Hepatocellular; Chondroitin; Female; Glycosaminoglycans; Heparin; Heparitin Sulfate; Liver; Liver Neoplasms; Pregnancy; Rats; Sulfates

1976
The glycosaminoglycans in human hepatic cancer.
    Cancer research, 1975, Volume: 35, Issue:3

    A method is proposed for the analysis of glycosaminoglycans that were isolated from human liver, combining cellulose acetate electrophoresis and enzymatic digestion with mucopolysaccharidases. The major constituent of glycossaminoglycans in the healthy liver is heparin sulfate and/or heparin (about 65%), with approximately equal quantities of dermatan sulfate and hyalauronic acid (about 13.5 and 13%, respectively) and a small amount of chondroitin sulfate. These components, especially chondroitin sulfate and hyaluronic acid, are markedly increased in hepatic carcinomas.

    Topics: Adenoma, Bile Duct; Carcinoma, Hepatocellular; Chondroitin; Dermatan Sulfate; Electrophoresis; Glycosaminoglycans; Heparin; Heparitin Sulfate; Humans; Hyaluronic Acid; Hydrolysis; Liver; Liver Neoplasms

1975
Stimulation of synthesis of free chondroitin sulfate chains by beta-D-xylosides in cultured cells.
    The Journal of biological chemistry, 1975, Jul-25, Volume: 250, Issue:14

    Beta-Xylosides stimulate 2- to 6-fold the synthesis of glycosaminoglycans by three types of nonconnective tissue cells (RG-C6, NB41A, and rat hepatoma cells, and normal and simian virus 40 (SV40)-transformed normal human skin fibroblasts. The effect, which is specific for the anomeric linkage and the glycone, is observed in the presence and absence of puromycin. Beta-Xylosides may substitute for xylosylated core protein as initiators of synthesis of chondroitin sulfate chains. No stimulation of synthesis of heparan sulfate was observed. With the use of a fluorogenic xyloside, 4-methylumbelliferyl-beta-D-xyloside, it was demonstrated that the free chondroitin sulfate chains secreted into the medium bear the xyloside at the reducing end, and have an average molecular weight of 16,500.

    Topics: Animals; Carcinoma, Hepatocellular; Cells, Cultured; Chondroitin; Chromatography, Gel; Dermatan Sulfate; Fibroblasts; Galactose; Glycosaminoglycans; Glycosides; Heparitin Sulfate; Humans; Hyaluronic Acid; Hymecromone; Liver Neoplasms; Mice; Neuroblastoma; Neuroglia; Nitrophenols; Rats; Simian virus 40; Skin; Spectrometry, Fluorescence; Sulfur Radioisotopes; Sulfuric Acids; Tritium; Xylose

1975
The isolation and characterization of glycopeptides and mucopolysaccharides from plasma membranes of an ascites hepatoma, AH 130.
    Journal of biochemistry, 1975, Volume: 78, Issue:5

    Plasma membranes were isolated from an ascites hepatoma, AH 130, by the fluorescein mercuric acetate (FMA) method. Glycopeptides and mucopolysaccharides were prepared by digesting the membranes with pronase, then by fractionating the digest chromatographically and electrophoretically. Isolated fractions were analyzed for their amino acid and carbohydrate compositions. Results were compared with those for corresponding fractions from AH 66 (J. Biochem. 76, 319-333 (1974)). Mucopolysaccharides and a series of glycopeptides were isolated from the fraction excluded from Sephadex G-50. The mucopolysaccharides were identified as a family of heparan sulfates with different electrophoretic mobilities. The glycopeptides contained serine, threonine, galactose, galactosamine, glucosamine, and sialic acid as the major constituents as aspartic acid and mannose as minor ones. This suggests that most of the carbohydrate moieties are linked to serine or threonine (O-glycosidic), and that some are linked to asparagine (N-glycosidic). No nearly purely O-glycosidic glycopeptides were found in this fraction from AH 130, through they were the major glycopeptides from the AH 66 plasma membranes. In the fraction included in the gel, glycopeptides containing fucose, galactose, mannose, glucosamine, glaactosamine, and sialic acid were found. The presence of galactosamine suggests that some of the glycopeptides are O-glycosidic though most are N-glycosidic. In the corresponding fraction from AH 66, nearly purely N-glycosidic glycopeptides were found.

    Topics: Animals; Aspartic Acid; Carcinoma, Hepatocellular; Cell Membrane; Female; Glycopeptides; Glycosaminoglycans; Heparitin Sulfate; Hexosamines; Hexoses; Liver Neoplasms; Rats; Serine; Sialic Acids; Sulfuric Acid Esters; Threonine

1975
The isolation and characterization of glycopeptides from plasma membranes of an ascites hepatoma, AH 66.
    Journal of biochemistry, 1974, Volume: 76, Issue:2

    Topics: Amino Acids; Animals; Carcinoma, Hepatocellular; Cell Membrane; Centrifugation, Density Gradient; Chromatography, Gel; Chromatography, Ion Exchange; Electrophoresis; Female; Fucose; Galactosamine; Galactose; Glucosamine; Glucose; Glycopeptides; Heparitin Sulfate; Inositol; Liver Neoplasms; Mannose; Microscopy, Phase-Contrast; Molecular Weight; Protein Binding; Rats; Sialic Acids; Sulfur Radioisotopes; Tritium; Uronic Acids

1974