Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:4.2.2.7 (heparinase)
 1,270 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Glycosaminoglycans have been characterized from a normal human breast cell line (HBL-100) and two different cell lines from human breast carcinoma (MDA-MB-231 and MCF-7). The glycosaminoglycans were labeled by exposure of cell cultures to [3H]glucosamine and [35S]sulfate and then isolated from both spent media and cells by pronase digestion and cetylpyridinium chloride fractionation. They were further characterized by (a) hexosamine composition, (b) controlled-pore glass exclusion chromatography, (c) reactivity with specific enzymes (hyaluronidase chondroitinase, heparitinase, and heparinase), (d) nitrous acid degradation, and (e) DEAD-Sephadex chromatography. The results indicate that the HBL-100 line synthesizes mainly hyaluronic acid, most of which is secreted into the medium. Chondroitin sulfate and heparan sulfate are the predominant glycosaminoglycans synthesized by the cancer lines; both are found mainly in the spent medium, but the hyaluronic acid synthesized by the MDA-MB-231 line remains cell associated. The cell-associated heparan sulfate had a molecular weight in excess of 13,000 and may contain linkages susceptible to testicular hyaluronidase. The MCF-7 cells produce significantly lower amounts of glycosaminoglycans than do the other two lines.
Cancer Res 1979 Mar
PMID:Glycosaminoglycans of normal and malignant cultured human mammary cells. 42 76

Two AKR lymphoma variants of low (LM) and high (HM) malignancy were characterized for cell properties important for metastatic capacity. Previous data suggested that these murine lymphoma variants differed in the late phase of metastasis. In the present study we attempted to determine more accurately the stage in which they differ. The HM cells attached less efficiently than the LM ones to both endothelial cells (5 times) and extracellular matrix (twice), possibly indicating a more efficient extravasation capacity of the HM cells. The level of heparinase was low in the two variant cells. Attachment to liver sections was, however, more efficient with the HM than with the LM cells.
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PMID:Cellular functions related to metastasis differing between low- and high-malignancy variants of AKR lymphoma. 162 61

The synthesis and secretion of mucin-like high-molecular glycoprotein was studied in 2 human colon cancer cell lines that spontaneously differentiate in culture (Caco-2 and T84) and in 2 cell lines that do not spontaneously differentiate (LS174T and HT29). Mucin, quantitated by 3H-glucosamine labelling and chromatography on Sepharose CL-4B was found to be produced by all 4 cell lines. The mucinous nature of the labelled high-molecular glycoprotein was verified by enzymatic degradation treatments (heparinase, hyaluronidase, chondroitinase ABC, and N-glycanase), alkaline-borohydride treatment, inhibition of labelling by the glycosylation inhibitor benzyl-alpha-GalNAc, and by CsCl-density-gradient centrifugation. In all 4 cell lines, an inverse correlation of mucin synthesis with cell density was demonstrated. In Caco-2 cells, the spontaneous post-confluent enterocytic differentiation with increased brush-border enzyme expression was associated with a decrease in mucin synthesis and in the activities of polypeptidyl GalNAc transferase and beta 1,3-galactosyltransferase activity. Using cDNA probes for 2 distinct human intestinal mucins (MUC2 and MUC3), we found that all 4 colon cancer cell lines expressed mucin message, but the types of mucin mRNA expressed differed. These data indicate that mucin-like glycoproteins can be synthesized by cell lines derived from non-mucinous colon cancer, whether or not they undergo spontaneous differentiation in culture. These cell lines may serve as in vitro models for studying apomucin heterogeneity and control of mucin gene expression.
Int J Cancer 1992 Jan 02
PMID:Mucin synthesis and secretion in relation to spontaneous differentiation of colon cancer cells in vitro. 172 5

Constituents of the bone marrow microenvironment have the capacity to influence both normal and malignant hematopoietic cell behavior. For example, HL-60 human promyelocytic leukemia cells in vitro display a more mature phenotype when grown on a bone marrow stroma-derived matrix. To elucidate which component(s) of the stromal matrix is capable of modulating HL-60 cell phenotype, matrices were treated with a variety of chemicals and enzymes prior to being used in the differentiation assay. Treatment of matrices with collagenase, pronase, chondroitinase, or chloroform:methanol:ether could not abolish the differentiation-promoting activity of bone marrow stroma. In contrast, the activity was destroyed by alkali treatment (0.5 M NaOH for 18 h) or heparinase/heparitinase enzymes. Heparin added to cultures increased maturation of HL-60 cells as determined by esterase production, Fc rosette formation, and morphological appearance. Other stromal components such as laminin, fibronectin, collagen I, collagen IV, or chondroitin sulfate did not alter the HL-60 leukemia cell phenotype. Stroma-derived matrix material which labeled with [35S]sulfate and eluted on a DEAE ion-exchange column as a high ionic fraction in 1.5 M LiCl and 7.5% sodium dodecyl sulfate contained the active fraction. A heparan sulfate proteoglycan component isolated by polyacrylamide-agarose gel electrophoresis induced a more mature HL-60 phenotype, and digestion with heparinase/heparitinase in the presence of protease inhibitors abrogated the effects on HL-60 phenotype. We conclude that a heparan sulfate-associated fraction of the bone marrow matrix plays a key role in the regulation of leukemic cell maturation.
Cancer Res 1990 Jun 15
PMID:A heparan sulfate-containing fraction of bone marrow stroma induces maturation of HL-60 cells in vitro. 214 Feb 91

We have examined the adhesion of primary Sertoli cells to a seminiferous tubule basement membrane (STBM) preparation in vitro. The STBM isolation procedure (Watanabe, T.K., L.J. Hansen, N.K. Reddy, Y.S. Kanwar, and J.K. Reddy, 1984, Cancer Res., 44:5361-5368) yields segments of STBM that retain their histotypic form in both three-dimensional tubular geometry and ultrastructural appearance. The STBM sleeves contain two laminae: a thick, inner basal lamina that was formed in vivo between Sertoli cells and peritubular myoid cells; and a thinner, outer basal lamina that was formed between myoid cells and sinusoidal endothelial cells. Characterization by immunofluorescence and SDS PAGE revealed that the isolated STBM retained fibronectin, laminin, and putative type IV collagen among its many components. When the STBM sleeves were gently shaken with an enriched fraction of primary Sertoli cells, the Sertoli cells bound preferentially to the lumenal basal lamina at the ends of the STBM sleeves. Few Sertoli cells bound to either the outer basal lamina of the STBM sleeves or to vascular extracellular matrix material which contaminated the STBM preparation. 3T3 cells, in contrast, bound to all surfaces of the STBM sleeves. Pretreatment of the STBM sleeves with proteases, 0.1 M Na metaperiodate, 4 M guanidine HCl, or heating to 80 degrees-90 degrees C inhibited lumenal Sertoli cell binding, but binding was not inhibited by chondroitinase ABC, heparinase, hyaluronidase, or 4 M NaCl. The lumenal Sertoli cell binding occurred in the presence or absence of added soluble laminin, but not fibronectin. The addition of soluble laminin, but not fibronectin, restored random binding of Sertoli cells to trypsinized STBM sleeves. Our in vitro model system indicates that Sertoli cells recognize differences in two basal laminae produced in vivo on either side of myoid cells.
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PMID:Sertoli cell binding to isolated testicular basement membrane. 352 69

Previous studies have suggested that mucin gene expression is tissue-specific; however, the relationship between unique mucin gene products and the biochemical properties of mucins is unknown. The purpose of this study was to determine the biochemical and molecular characteristics of mucin synthesized by adenocarcinoma cell lines derived from breast (ZR-75-1), stomach (MGC-803), pancreas (Capan-2), and lung (Chago K-1). Mucin was quantitated by [3H]glucosamine labeling and Sepharose CL-4B chromatography. The mucinous nature of the labeled high molecular weight glycoproteins (HMG) was verified by alkaline borohydride treatment, cesium chloride density gradient ultracentrifugation, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Specific mucin gene expression was determined using cDNA probes for 2 distinct intestinal mucins (MUC-2 and MUC-3) and one breast cancer mucin (MUC-1). Specific core mucin proteins were confirmed by immunoblots using antibodies that recognize MUC-1, MUC-2, and MUC-3 core peptides. These experiments demonstrate that all cell lines contained HMG in the medium, cytosol, and membrane fractions. The HMG was mucinous in breast, pancreatic, and lung cell lines. In contrast, most of the HMG secreted by the gastric cell line was proteoglycan-like, due to its susceptibility to hyaluronidase, heparinase, and chondroitinase avidin-biotin complex. Ion-exchange (DEAE-Sephacel) chromatography of [3H]glucosamine-labeled HMG demonstrated that the acidic or basic nature of the mucin was different in all cancer cell lines tested. Despite these differences, mRNA and immunoblot analysis suggest that all cell lines predominantly express MUC-1 apomucin, small amounts of MUC-2 apomucin, and no MUC-3. Immunoprecipitation of MUC-1-type mucin using the 139H2 monoclonal antibody demonstrated that different sizes of mucin peptides were present in all cell lines, corresponding to the known length polymorphism of this mucin. The amount and nature of carbohydrate epitopes were analyzed by immunoblots using anti-T (peanut lectin), anti-Tn (91S8 monoclonal antibody), and anti-sialosyl Tn (JT10e monoclonal antibody). T and Tn antigens were significantly higher in breast and pancreatic cells as compared with lung and gastric cell lines. These findings correlated with increased activities of polypeptidyl N-acetylgalactosaminyl transferase and beta-1,3-galactosyltransferase.(ABSTRACT TRUNCATED AT 400 WORDS)
Cancer Res 1993 Mar 15
PMID:Mucin synthesis and secretion in various human epithelial cancer cell lines that express the MUC-1 mucin gene. 844 22

The MCF-7 breast cancer cells exhibit remarkable growth enhancement in response to basic fibroblast growth factor (FGF-2) stimulation in a dose dependent manner. To investigate the involvement of proteoglycans on control of FGF-2 induced proliferation, polysaccharide chains were degraded by specific enzymes. Our results showed that MCF-7 cells were unsensitive to FGF-2 after enzymatic degradation of heparin sulfate proteoglycans (HSPG) by heparinase. After metabolic inhibition of sulphation by sodium chloride, radiolabelled proteoglycans were purified and quantified by ion exchange chromatography. Sodium chlorate treatment reduced by 70% sulfation of proteoglycans. This decrease of sulphation totally inhibited FGF-2-mediated proliferation. The sulphated glycosaminoglycans which were critical in FGF-2-induced proliferation were strictly HSPG, as an addition of heparin in cell culture medium can restore FGF-2 mitogenic activity. In contrast, other glycosaminoglycans (chondroitin sulfate/hyaluronic acid) did not show any effect. These results provide clear evidence for the critical role of HSPG in FGF-2-induced proliferation on MCF-7 breast cancer cells.
Bull Cancer 1996 Feb
PMID:[Involvement of sulfated proteoglycans in the control of proliferation of MCF-7 breast cancer cells]. 865 6

Alkaline phosphatase, a marker of differentiation in the human alveolar adenocarcinoma cell line A549, is inducible by conditioned medium from lung fibroblasts and by cytokines including oncostatin M and interleukin 6, but only in the presence of a glucocorticoid, dexamethasone. Dexamethasone was shown to induce incorporation of [3H]glucosamine into three fractions of medium and cell trypsinate from subconfluent A549 cells, eluting from DEAE ion-exchange chromatography. The first peak did not correspond to any of the unlabelled glycosaminoglycans and was not characterized further. Induction was seen in two other peaks, corresponding to hyaluronic acid and heparan sulphate. Of these, heparan sulphate, eluting as one well-defined peak (referred to as HS1) and another of lower activity and less well defined (HS2), was selected as the most likely to interact with growth factors and cytokines and was isolated from the eluate, concentrated and desalted, and used in alkaline phosphatase induction experiments in place of dexamethasone. HS1 isolated from the medium (HS1m) of subconfluent A549 cells was shown to replace dexamethasone in induction experiments with fibroblast-conditioned medium, oncostatin M and interleukin 6. HS1 from the cell trypsinate and HS2 from the medium and trypsinate were inactive. As the activity of HS1m could be abolished by heparinase and heparitinase but not by chondroitinase ABC, it was concluded that HS1m was a fraction of heparan sulphate involved in the regulation of paracrine growth factor activity in lung fibroblast-conditioned medium, and in the regulation of other growth factors with potential roles in the paracrine control of cell differentiation.
Br J Cancer 1997
PMID:Activation of paracrine growth factors by heparan sulphate induced by glucocorticoid in A549 lung carcinoma cells. 925 93

We report a detailed analysis of heparan sulfate (HS) structure using a model of human colon carcinogenesis. Metabolically radiolabeled HS was isolated from adenoma and carcinoma cells. The chain length of HS was the same in both cell populations (Mr 20,000; 45-50 disaccharides), and the chains contained on average of two sulfated domains (S domains), identified by heparinase I scission. This enzyme produced fragments of approximate size 7 kDa, suggesting that the S domains were evenly spaced in the intact HS chain. The degree of polymer sulfation and the patterns of sulfation were strikingly different between the two HS species. When compared with adenoma HS, the iduronic acid 2-O-sulfate content of the carcinoma-derived material was reduced by 33%, and the overall level of N-sulfation was reduced by 20%. However, the level of 6-O-sulfation was increased by 24%, and this was almost entirely attributable to an enhanced level of N-sulfated glucosamine 6-O-sulfate, a species whose data implied was mainly located in the mixed sequences of alternating N-sulfated and N-acetylated disaccharides. The results indicate that in the transition to malignancy in human colon adenoma cells, the overall molecular organization of HS is preserved, but there are distinct modifications in both the S domains and their flanking mixed domains that may contribute to the aberrant behavior of the cancer cell.
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PMID:Heparan sulfate undergoes specific structural changes during the progression from human colon adenoma to carcinoma in vitro. 941 46

Many matrix metalloproteinases (MMPs) are tightly bound to tissues; matrilysin (MMP-7), although the smallest of the MMPs, is one of the most tightly bound. The most likely docking molecules for MMP-7 are heparan sulfate proteoglycans on or around epithelial cells and in the underlying basement membrane. This is established by extraction experiments and confocal microscopy. The enzyme is extracted from homogenates of postpartum rat uterus by heparin/heparan sulfate and by heparinase III treatment. The enzyme is colocalized with heparan sulfate in the apical region of uterine glandular epithelial cells and can be released by heparinase digestion. Heparan sulfate and MMP-7 are expressed at similar stages of the rat estrous cycle. The strength of heparin binding by recombinant rat proMMP-7 was examined by affinity chromatography, affinity coelectrophoresis, and homogeneous enzyme-based binding assay; the K(D) is 5-10 nM. Zymographic measurement of MMP-7 activity is greatly enhanced by heparin. Two putative heparin-binding peptides have been identified near the C- and N-terminal regions of proMMP-7; however, molecular modeling suggests a more extensive binding track or cradle crossing multiple peptide strands. Evidence is also found for the binding of MMP-2, -9, and -13. Binding of MMP-7 and other MMPs to heparan sulfate in the extracellular space could prevent loss of secreted enzyme, provide a reservoir of latent enzyme, and facilitate cellular sensing and regulation of enzyme levels. Binding to the cell surface could position the enzyme for directed proteolytic attack, for activation of or by other MMPs and for regulation of other cell surface proteins. Dislodging MMPs by treatment with compounds such as heparin might be beneficial in attenuating excessive tissue breakdown such as occurs in cancer metastasis, arthritis, and angiogenesis.
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PMID:Heparan sulfate proteoglycans as extracellular docking molecules for matrilysin (matrix metalloproteinase 7). 1066 May 81


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