Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

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Query: EC:3.2.1.23 (beta-galactosidase)
14,648 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In order to clarify the relationship between hydrolases and the invasion of gastric carcinoma, both fibronectin and proteoglycan in pericancerous matrix and beta-galactosidase activity in gastric carcinoma were investigated by means of histochemical, immunohistochemical and ruthenium red electrocytochemical stains. The results showed that the activity of beta-galactosidase in mucous cell carcinoma was more intensive than that in well-differentiated and poorly-differentiated adenocarcinoma. RR granules and fibronectin were not found in the pericancerous matrix close to the mucous cell carcinoma, but were obtained in the region far from the mucous cell carcinoma. Nevertheless, both of them were present and intact near the well-differentiated adenocarcinoma. The result of this study suggests that mucous cell carcinoma may secrete beta-galactosidase into the surrounding matrix, inducing degradation of proteoglycan and fibronectin in favour of further infiltration and metastasis.
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PMID:[The relationship between hydrolases and invasion of gastric carcinoma]. 166 9

The ability to express recombinant genes in vivo offers potential new treatments for human disease if questions of safety and toxicity can be addressed. Complications of gene transfer could include, for example, overexpression of introduced genes for growth or angiogenic factors or insertional mutagenesis, both of which could cause uncontrolled cell growth. We report the development of a suicide retroviral vector that provides a method to eliminate cells undergoing rapid growth in vivo. A murine amphotropic retroviral vector was constructed in which the gene for herpesvirus thymidine kinase was included to render proliferating cells sensitive to ganciclovir, and the Escherichia coli beta-galactosidase gene served as a reporter. This vector's efficacy was first assessed in vitro, and beta-galactosidase activity was abolished in several cell lines after treatment with ganciclovir. In vivo, a transplantable murine CT26 adenocarcinoma whose cells were transduced with this vector regressed completely after administration of ganciclovir. In contrast, expression in nondividing cells within rabbit arteries transduced by retroviral infection in vivo was unaffected. This suicide vector therefore eliminates transformed cells but allows survival of normal nondividing cells that express its specific recombinant genes in vivo, and may thus improve the safety and efficacy of gene transfer into living organisms.
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PMID:Selective elimination of recombinant genes in vivo with a suicide retroviral vector. 175 52

The spontaneous differentiation of CaCo-2 human colonic adenocarcinoma cells to enterocytes in culture is associated with a decrease in polylactosaminoglycans, particularly those attached to the lysosomal membrane glycoprotein h-lamp-1 (Youakim et al., Cancer Res., 49:6889-6895, 1989). To elucidate the biosynthetic mechanisms leading to these alterations we have compared glycosyltransferase activities that are involved in the synthesis of polylactosaminoglycans and of the N- and O-glycan structures that provide the framework for the attachment of these chains. Glycosyltransferase activities in cell homogenates obtained from undifferentiated and differentiated CaCo-2 cells were assayed by high pressure liquid chromatography separation of enzyme products. The beta-galactosidase activities and extremely high pyrophosphatase activities in differentiated cells were effectively inhibited by 5 mM gamma-galactonolactone and 10 mM AMP, respectively. CaCo-2 cells contain most of the enzymes that are involved in N-glycan branching [N-acetylglucosamine (GlcNAc) transferases I to V] with the exception of GlcNAc transferase VI. The levels of GlcNAc transferase I activities were comparable in undifferentiated and differentiated cells, but GlcNAc transferase II to V activities were significantly increased upon differentiation. The enzyme activities that are directly involved in the synthesis of linear polylactosaminoglycans (Gal beta 4GlcNAc beta 3- repeating units), blood group i UDP-GlcNAc:Gal beta-R beta 3-GlcNAc transferase and UDP-Gal:GlcNAc beta 4-Gal transferase, were found at similar levels in undifferentiated and differentiated CaCo-2 cells. Since GlcNAc transferase III activity is known to inhibit further branching and galactosylation, these results suggest that its increased activity in differentiated CaCo-2 cells may be partly responsible for the decreased synthesis of fucosylated polylactosaminoglycans. Differentiated cells showed a 2-fold increase in O-glycan core 2 UDP-GlcNAc:Gal beta 3GalNAc alpha-R [GlcNAc to N-acetylgalactosamine (GalNAc)] beta 6-GlcNAc transferase activity. In contrast, O-glycan core 1 UDP-Gal:GalNAc alpha-R beta 3-Gal transferase activity was found decreased. Several enzymes that are found in homogenates from normal human colonic tissue are absent or barely detectable in CaCo-2 cells. These include blood group I UDP-GlcNAc:GlcNAc beta 3Gal beta-R (GlcNAc to Gal) beta 6-GlcNAc transferase, O-glycan core 3 UDP-GlcNAc:GalNAc alpha-R beta 3 GlcNAc transferase and O-glycan core 4 UDP-GlcNAc:GlcNAc beta 3GalNAc-R (GlcNAc to GalNAc) beta 6-GlcNAc transferase.
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PMID:Glycosyltransferase changes upon differentiation of CaCo-2 human colonic adenocarcinoma cells. 190 2

Lacto-series glycolipids, comprising two isomeric types distinguished as type 1 or 2 based upon the linkage of the terminal galactose of the chains, form the basis for a diversity of cell surface antigens expressed on cells. Experimentally, type 2 chain precursors are generally more abundant in tissues for extractive purposes to yield rather large quantities of material compared to the type 1 chain structures. Conditions have been defined for in vitro conversion of terminal Gal beta 1----4GlcNAc linkages of type 2 chain precursors to yield type 1 lacto-series chain based terminal Gal beta 1----3GlcNAc structures in 5- to 10-mg amounts or higher. The terminal galactose of underivatized type 2 chain structures is removed by hydrolysis with jack bean beta-galactosidase followed by transfer of galactose in beta 1----3 linkage catalyzed by a beta 1----3-galactosyltransferase from human colonic adenocarcinoma Colo 205 cells which was first depleted of beta 1----4-galactosyltransferase by chromatography on alpha-lactalbumin-Sepharose. Scaled-up reaction mixtures provided a final yield of product after isolation of about 90% from the immediate Lc3Cer precursor in the 5-mg product range. The biosynthetic product was subjected to extensive chemical analysis by 1H NMR and mass spectrometric methods. These results indicated the presence of a high purity terminal Gal beta 1----3-linked product. The amount of material was sufficient for nondestructive characterization by 2-D NMR, with subsequent confirmation of structure by +FAB-MS and methylation analysis by GC-MS. The results indicate an effective means to rapidly generate lacto-series type 1 precursors in vitro as a superior alternative to direct tissue extractive procedures.
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PMID:Preparative in vitro generation of lacto-series type 1 chain glycolipids catalyzed by beta 1----3-galactosyltransferase from human colonic adenocarcinoma Colo 205 cells. 250 75

A factor that cross reacts with the carcinoembryonic antigen (CEA), which we call P factor, was isolated from normal human plasma. To demonstrate the difference between this P factor and the nonspecific cross-reacting antigen (NCA), the same anti-CEA serum was absorbed in an identical manner with both the antigens. Absorption was checked by immunohistochemistry by the beta-galactosidase procedure on sections of colonic adenocarcinoma and normal colonic mucosa. The unabsorbed antiserum recognizes both tissues; after absorption with NCA the staining becomes paler on both tissues, but maintains color on the normal colonic mucosa and granulocytes. Only absorption with the P factor will give an unstained field of normal colonic mucosa, thus revealing the tumor structure. Data obtained by us suggest that the NCA (tissue extract) is an antigen that is not suitable to the absorption of anti-CEA serum for immunocytochemistry techniques, whereas the P factor (plasma extract) appears to be utilizable with good results.
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PMID:Two CEA cross-reacting antigens: differences in absorbing the same anti-CEA serum. 356 3

MAT-B1 and MAT-C1 ascites sublines of the 13762 rat mammary adenocarcinoma both contain sialomucin as a major cell surface component and are resistant to cytolysis by normal rat spleen lymphocytes [3 +/- 2% (SD) and 0 +/- 1%, respectively]. Susceptibility to lysis did not increase following treatment of cells with neuraminidase, fucosidase, or alpha- or beta-galactosidase. Treatment with trypsin significantly increased the susceptibility of MAT-B1 (14 +/- 3%) but not MAT-C1 (5 +/- 2%). Following 1 month in culture, the sialomucin content of MAT-B1 cells dropped from 30% to 8% (determined by glucosamine labeling) and natural cell-mediated cytolysis increased to 16 +/- 4%, whereas the sialomucin content and susceptibility of MAT-C1 cells did not change. The results indicate that the relatively minor changes associated with removal of cell surface sialic acid or fucose residues do not result in increased susceptibility of the ascites cells to cytolysis. However, susceptibility of MAT-B1 cells to lysis by normal rat spleen lymphocytes was inversely correlated with the amount of major glycoprotein (r = -0.96).
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PMID:Cell surface sialomucin and resistance to natural cell-mediated cytotoxicity of rat mammary tumor ascites cells. 373 Nov 8

Monoclonal IgG1 antibodies 2C8 and 2F7, derived by immunization of mice with a glycoprotein-enriched fraction of human ovarian adenocarcinoma, recognized a 60 kD glycoprotein in the ovarian tumor but not in normal ovary. Survey of other normal adult tissues by an indirect solid-phase radioimmunoassay (RIA) revealed the presence of the antigen in trace amounts in various normal organs such as small intestine, liver colon and urinary bladder, except in lung where its concentration was as high as in tumors. Among fetal tissues tested, intestine and placenta had the highest activities. By RIA, about 50% of ovarian and colonic tumors had elevated levels of the antigen. All ovarian cyst fluids, both benign as well as malignant, also contained a high level of the antigen. Immunodepletion studies indicated that the antigen was distinct from carcinoembryonic antigen and the ovarian cancer antigens described in our laboratory with other monoclonal antibodies. The antigen bound to Con A-Sepharose and was eluted with 2% alpha-D-mannoside, was soluble in 0.6 M perchloric acid and stable at 100 degrees C for 30 min. The antigenic activity in isolated plasma membrane enriched fractions of ovarian adenocarcinomas was sensitive to trypsin, chymotrypsin or protease treatment but unaffected by neuraminidase, beta-galactosidase, periodate or methanol treatment. By immunoperoxidase staining, the antigen was localized in a variety of human tumors showing widespread distribution.
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PMID:Production and characterization of monoclonal antibody to a 60-kD glycoprotein in ovarian carcinoma. 389 88

The MAT-B1 and MAT-C1 ascites sublines of the 13762 rat mammary adenocarcinoma, which differ in several cell surface properties, contain a major mucin-type glycoprotein, termed ASGP-1. The sialic acid content of MAT-C1 ASGP-1 is 2-3-fold greater than MAT-B1 ASGP-1 (Sherblom, A. P., Buck, R. L., and Carraway, K. L. (1980) J. Biol. Chem. 255, 783-790). Sialic acid analysis demonstrated that, whereas MAT-C1 ASGP-1 contained approximately equal amounts of N-acetylneuraminic acid (NeuAc) and N-glycolylneuraminic acid (NeuGl), MAT-B1 ASGP-1 was devoid of NeuGl. MAT-B1 microsomes also did not contain NeuGl. MAT-B1 cells incubated with [3H]N-acetylmannosamine did not synthesize either labeled CMP-NeuGl or free NeuGl, even though the CMP-sialic acid synthetase was active with the substrate NeuGl. Thus, MAT-B1 cells may be deficient in the enzyme N-acetylneuraminate monooxygenase. The O-linked oligosaccharides from both MAT-B1 and MAT-C1 ASGP-1 have been shown to contain a core tetrasaccharide Gal(beta 1-4)GlcNAc(beta 1-6)(Gal(beta 1-3]GalNAc in which both galactose residues may be linked to additional sugars (Hull, S. R., Laine, R. A., Kaizu, T., Rodriquez, I., and Carraway, K. L. (1984) J. Biol. Chem. 259, 4866-4877). The distribution of NeuAc and NeuGl between the two galactose termini of the core tetrasaccharide was examined for MAT-C1 ASGP-1. Oligosaccharides were released by alkaline-borohydride treatment of MAT-C1 ASGP-1 which had been labeled with [14C]glucosamine and galactose oxidase/B3H4. Following fractionation by Bio-Gel P-4, DEAE-Sephadex, and high-performance liquid chromatography, oligosaccharides were analyzed for NeuAc and NeuGl and for susceptibility to digestion with beta-galactosidase. Three disialylated oligosaccharides were identified containing 2 mol of NeuAc (5.5% recovery), 2 mol of NeuGl (4.5%), or 1 mol each of NeuAc and NeuGl (11.1%). For monosialylated oligosaccharides, NeuGl appeared preferentially associated with the Gal(beta 1-4)GlcNAc terminus (9.0%), whereas significant amounts of oligosaccharide containing NeuAc at both the Gal(beta 1-3)GalNAc (2.6%) and Gal(beta 1-4)GlcNAc (4.5%) termini were detected. Each of the major qualitative differences between MAT-B1 and MAT-C1 oligosaccharides, including the presence of NeuGl (MAT-C1), sulfate (MAT-B1), and alpha-linked galactose (MAT-B1), occurs at the Gal(beta 1-4)GlcNAc terminus.
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PMID:N-Acetylneuraminic acid and N-glycolylneuraminic acid in the O-linked oligosaccharides of a tumor cell glycoprotein. Incorporation and distribution. 391 40

The activities of six glycosidases in a rat colorectal adenocarcinoma were measured and compared with those of normal colonic mucosa. The specific activities of beta-galactosidase (EC 3.2.1.23) and beta-glucuronidase (EC 3.2.1.31) in the adenocarcinoma were similar to those of the corresponding ones in the normal mucosa, whereas those of beta-N-acetylglucosaminidase (EC 3.2.1.30), alpha-L-fucosidase (EC 3.2.1.51), alpha-galactosidase (EC 3.2.1.22) and beta-glucosidase (EC 3.2.1.21) were reduced in the former as compared with those in the latter. In the case of alpha-L-fucosidase, two forms were newly detected in the tumor. The relative abundance of three forms of beta-N-acetylglucosaminidase was quite different between the adenocarcinoma and the normal mucosa, and the level of the intermediate form in the tumor was markedly reduced. However, thermostability and Km values of two forms A and B in the tumor were not different from those of the corresponding ones in the normal tissue.
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PMID:Alteration in glycosidases from well-differentiated colorectal adenocarcinoma of rat. 404 71

It has been shown by us that the human blood-group MN antigenic determinants are not the products of allelomorphic genes as believed so far, but that N is the precursor substance of M and that the allelomorph to the M gene is amorph. The determinant structure of the N antigen is branched and possesses as non-reducing termini beta-d-galactopyranosyl (Gal) and alpha-N-acetylneuraminic acid (NANA) linked to beta-Gal. The M substance differs from N only in that alpha-NANA covers the terminal beta-Gal of the N determinant. Vicia graminea anti-N reacts with terminal beta-Gal of the N antigen as well as its precursor. A human blood-group N-like antigen in the cell surface of the TA3 mammary adenocarcinoma (ascites form) has been found by us. The TA3 cancer occurs as the non-strain specific Ha subline and as the strain-specific St subline. This is the first description of an N-like antigen in a non-primate as well as a tumor. This antigen reacts with Vicia anti-N. In serological specificity the Vicia agglutinin is closely related to the Thomsen-Friedenreich anti-T agglutinin present in most human and animal sera. These sera plus complement kill ordinary TA3-St cells and sialidase-treated Ha cells to less than 95 percent. Untreated TA3-Ha cells are fully resistant even though they absorb cytotoxin. Beta-galactosidase treatment of either Ha or St cells abolishes the killing activity of the sera. The cancer cells absorb anti-T but they lose this capability after exposure to beta-galactosidase. An immunological cross-relationship between the human blood-group MN antigens and the receptor for an oncogenic virus, the avian subgroup B leukosis sarcoma virus has been observed.
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PMID:Relation of human blood-groups MN to cancer cell surface antigens and to receptors for oncogenic viruses. 414 44


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