Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0019204 (hepatocellular carcinoma)
 71,386 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

It was found that a human hepatoma-associated ALP (orthophosphoric monoester phosphohydrolase, E.C. 3.1.3.1) shared electrophoretic mobility, inactivation by urea, inhibition by inorganic phosphate, ethylenediaminetetraacetate, and amino acids (L-phenylalanine, L-leucine and L-homoarginine), heat stability, sensitivity to neuraminidase, pH optimum, Km value, and antigen site with fast moving ALP isozymes of FL cell strain derived from human amniotic membrane. However, 40-week-old fresh amniotic membrane lacked this isozyme. Instead, it had a placental type ALP consisting of minor components. The other ALP isozyme of FL cells had properties common to hepatoma ALP with regard to L-phenylalanine sensitivity, inhibition by ethylenediaminetetraacetate, inactivation by urea, and antigen site, but differed from it in electrophoretic mobility, sensitivity to L-leucine and L-homoarginine, and the presence of another antigen site. It was more heat stable and more sensitive to inhibition by inorganic phosphate than Hepatoma AP. The possible regulatory mechanism between the hepatoma-type ALP and the placental type ALP in the amnion cells is considered.
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PMID:A hepatoma-associated alkaline phosphatase, the Kasahara isozyme, compared with one of the isozymes of FL amnion cells. 0 Sep 48

Human alpha-fetoprotein (HAFP) isolated by immunoadsorbent column was shown to suppress the mitogenic response of human lymphocytes to phytomitogens, antihuman thymocyte antiserum, and the mixed lymphocyte culture. HAFP isolated from the sera and ascitic fluid of five hepatoma patients, and from fetal liver, varied in biological potency over three orders of magnitude. Extended agarose gel electrophoresis and crossed immunoelectrophoresis demonstrated three molecular species of HAFP. Quantitation of the three species revealed a correlation between the relative amount of the most negatively charged species and biological potency. Treatment of HAFP with neuraminidase to remove completely sialic acid residues did not alter the biological potency, but converted the three species to two species having slower electrophoretic mobilities. We conclude that differences in sialic acid content are only partly responsible for the microheterogeneity demonstrated by HAFP, and that variability in another charged moiety is also present. Variation in the relative proportions of the different molecular species of HAFP may be important in the regulation of its immunosuppressive properties.
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PMID:Human alpha-fetoprotein as a modulator of human lymphocyte transformation: correlation of biological potency with electrophoretic variants. 6 52

Guinea pig T lymphocyte proliferation induced by sodium periodate (NaIO4) or neuraminidase-galactose oxidase (NG) occurs when lymphocytes and macrophages are cultured together after treatment of either purified T lymphocytes or macrophages with these agents. Regardless of which cell initially bears the modified surface carbohydrate, lymphocyte proliferation requires the presence of viable homologous macrophages and fails to occur when they are replaced with fibroblasts, erythrocytes, L2C leukemia cells, thymocytes, PMN, line I hepatoma cells, or murine macrophages. Lymphocyte proliferation resulting from NaIO4 or NG treatment of lymphocytes is diminished when these cells are treated with proteolytic enzymes or aged in in vitro culture for 48 hr. By contrast, proteolytic enzyme treatment or in vitro aging has no effect on the ability of NaIO4 or NG-treated macrophages to induce lymphocyte proliferation. The requirement for macrophage-lymphocyte interaction in NaIO4 or NG-induced lymphocyte proliferation is indicative of a central role for the macrophage in the initiation of T lymphocyte proliferation.
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PMID:The requirement for macrophage-lymphocyte interaction in T lymphocyte proliferation induced by generation of aldehydes on cell membranes. 17 Mar 38

Lectins, plant proteins that bind specific saccharide determinants, have been utilized to examine the effect of neuraminidase digestion on the structure and/or expression of oligosaccharide moieties present at the periphery of Novikoff ascites hepatoma cells. Five lectins were utilized: concanavalin A (Con A), specific for alpha-D-manno- or alpha-D-glucopyranosyl residues; wheat germ agglutinin, specific for 2-acetamido-2-deoxy-D-glucopyranosyl residues; Ricinus communis agglutinin I (RCAI), specific for D-glucopyranosyl residues; R. communis agglutinin II (RCAII), specific for D-galacto- or 2-acetamido-2-deoxy-D-galactopyranosyl residues; and soybean agglutinin, specific for 2-acetamido-2-deoxy-D-galactopyranosyl residues. Neuraminidase treatment of Novikoff cells did not alter their agglutination by Con A or wheat germ agglutinin. Similar treatment produced only a 2-fold increase in their agglutination by RCAI but a 12-fold increase in their agglutination by RCAII, indicating that 2-acetamido-2-deoxy-D-galactopyranosyl residues become expressed upon neuraminidase treatment. This conclusion was confirmed by the observation that neuraminidase-treated Novikoff cells acquired agglutinability by soybean agglutinin. Binding studies using ferritin-conjugated RCAII indicated that neuraminidase treatment exposed cryptic cell surface receptors for RCAII. To ascertain the role of cell surface glycoproteins in lectin-induced agglutination of Novikoff cells, glycopeptides cleaved from the cell surface by papain were assayed for lectin receptor activity. The cell surface glycopeptides exhibited receptor activity for Con A, wheat germ agglutinin and RCAI but not for RCAII and soybean agglutinin. A cell surface macrosialoglycopeptide fraction, resolved by gel filtration and ion-exchange chromatography, possessed a major portion of the Con A and RCAI receptor activity.
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PMID:Effect of neuraminidase and papain treatment on lectin-induced agglutination of Novikoff tumor cells and assay of lectin receptor activity of the glycopeptides released from the cell surface by papain. 17 11

The ascites form of a chemically induced guinea pig hepatoma, line-10, was resistant to killing in vitro by xenogeneic antibody and guinea pig complement. Pretreatment of line-10 cells with certain proteolytic enzymes rendered tham susceptible to the killing action of antibody and guinea pig complement. The effects of enzyme pretreatment were dependent on enzyme concentration, temperature, and could be blocked by addition of competitive or non-competitive inhibitors. The effect of the enzyme treatment could reversed by incubating the treated cells at 37 degrees C (but not at 0 degrees C), in the absence of the enzyme. Effective enzymes included ficin, bromelain, pronase, elastase, papain, trypsin, collagenase, lipases type I and type VI, and the neuraminidase preparation isolated from Clostridium perfringens. The activity of the lipase preparations and the neuraminidase preparation isolated from Clostridium perfringens appeared to be caused by proteolytic enzyme contamination. Enzyme preparations that proved ineffecitve in rendering the line-10 cells sensitive to killing by antibody and guinea pig complement included DNase, RNase, beta-glucuronidase type 6A or type B10, hyaluronidase type V or type VI, and pectinesterase.
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PMID:Lysis of tumor cells by antibody and complement. VI. Enhanced killing of enzyme-pretreated tumor cells. 17 70

The following three parameters were studied in Morris hepatomas of different growth rates: (a) the specific activity of guanosine dephosphate (GDP)-fucose:glycoprotein fucosyltransferase and cytidine monophosphate (CMP)-N-acetylneuraminic acid:glycoprotein sialyltransferase, (B) the content of GDP-fucosee and CMP-N-acetylneuraminic acid, and (c) the activity of alpha-L-fucosidase and neuraminidase. Fucosyltrasferase activities were significantly elevated in all hepatomas investigated. Especially high levels of enzyme were measured in the rapidly growing tumors 7777, 66, and 3924A. The increase varied between 2- and 3-fold when compared with the corresponding host liver. Conversely, the activity of the sialytransferase was greatly decreased in all hepatoma lines with a rapid or intermediate growth rate. In the fast-growing tumor 9618A2, the activity was reduced to 8%. GDP-fucose and CMP-N-acetylneuraminic acid were determined by the isotope dilution technique. In normal rat liver from Buffalo or ACl rats, the concentration of GDP-fucose was 6.5+/-0.9 and 9.5+/-1.1nmoles/g, wet weight, respectively. In the fast-growing hepatomas 3924A and 9121, levels up to 21.5 nmoles/g, wet weight, were found, However, the content of CMP-N-acetylneuraminic acid in hepatomas was indluenced to a lesser extent by the degree of differentiation of the tumor. In the most rapidly growing tumor, 9618A2, a level of alpha-L- fucosidase seven times higher than in host liver was determined. Moreover, there existed a correlation bewteen the age of the hepatoma and enzyme activity. Within the 2nd week after inoculation, fucosidase activity increased from 130 to 343 nmoles/hr/mg of protein. Neuraminidase was measured in a new linked assay system. The activity of this enzyme was lowered by 50% or was at least unchanged when compared to the activity in host liver. Our results indicate that specific alterations of fucose metabolism are a characteristic feature of Morris hepatomas.
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PMID:Glycosyltransferases and glycosidases in Morris hepatomas. 19 53

The binding of Line 10 hepatoma cells to normal syngeneic guinea pig macrophages is increased when the tumor cells are treated with neuraminidase and galactose oxidase (NAGO) before they are added to the macrophage monolayers. The effect is abolished by exposure of the NAGO-treated tumor cells to sodium borohydride. Line 1 hepatoma cells treated with NAGO or with sodium periodate are killed to a greater extent than untreated tumor cells. This effect can also be reversed by sodium borohydride. Further, periodate-treated macrophages become cytotoxic for unmodified tumor cells. These results demonstrate that increased tumor cell killing occurs when artificial contacts (presumably via Schiff bases) are established between normal macrophages and tumor cells. They are consistent with the hypothesis that close cell to cell contact is necessary for macrophage-mediated cytotoxicity.
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PMID:Increased binding and killing of neuraminidase-galactose oxidase-treated tumor cells by normal macrophages. 19 81

We examined 19 hepatoma tissues for alkaline phosphatase isoenzyme and found that six have both the Kasahara isoenzyme and an alkaline phosphatase with a unique electrophoretic mobility, in addition to the liver-type enzyme. From two of six carcinoma tissues, the abnormal enzyme was partly purified and subjected to a detailed analysis, which clarified that the abnormal enzyme resembled a fetal intestinal alkaline phosphatase in most of its enzymic and immunologic properties and also in properties that reflect enzyme structure. This fetal intestinal-type alkaline phosphatase was not found in 24 specimens of normal liver from adults. The relevance of fetal intestinal-type alkaline phosphatase to Kasahara isoenzyme and adult intestinal alkaline phosphatase is discussed. The fetal and adult intestinal alkaline phosphatases differ in electrophoretic mobility, heat stability, and reactivity with concanavalin A. The adult-type enzyme has two components; only the electrophoretically slower, neuraminidase-resistant one is described here.
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PMID:A fetal intestinal-type alkaline phosphatase in hepatocellular carcinoma tissue. 19 84

Cell-surface glycoprotein of 3 rat hepatoma strains and late-embryonic liver was metabolically labelled in vivo with [3H]- or [14C]-fucose. Trypsinization of the cells and exhaustive pronase digestion of combined hepatoma-liver trypsinates followed by gel filtration over Sephadex-Biogel mixtures, yielded elution profiles that contained more early-eluting (high-mol.-wt.) glycopeptides for hepatomas than for liver. At least 3 factors were identified which acted to augment the fraction of early-eluting tumour glycopeptides: (a) increase of neuraminidase-sensitive sialic acid, (b) increase of neuraminidase-insensitive sialic acid that was sensitive to mild HCl hydrolysis, and (c) presence of sugar sulphate groups contributing to a restricted extent, relative to possible unknown factor(s). Whether (a), (b) or (c) operated depended on the hepatoma strain or its mode of growth. Notwithstanding these differences in the nature of the increase in early-eluting glycopeptides, the increase itself appears not to be due to growth per se, nor to an embryonic expression, but rather may serve as a marker of tumourigenicity.
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PMID:Comparison of cell-surface glycoproteins of rat hepatomas and embryonic rat liver. 19 23

A novel alkaline phosphatase differing from the so-called liver-specific isoenzyme was found in four out of twenty-four normal adult livers. Although the mobility of this enzyme was the same as that of so-called liver-specific alkaline phosphatase on the polyacrylamide gel electrophoretogram, its mobility was not altered following neuraminidase treatment, while that of the liver-specific enzyme was affected by the same treatment. Both enzymes also differed in other enzymatic and immunologic properties. The enzyme, however, resembled the so-called intestinal alkaline phosphatase in many enzymatic and immunologic properties. Thus, the inhibition patterns by amino acids, EDTA and inorganic phosphate, the pH optima, KM values for phenyl phosphate and reactivity with anti-intestinal alkaline phosphatase antibody were quite similar for both enzymes. Differences in the properties of this enzyme and intestinal alkaline phosphatase were in sensitivity to denaturation by treatment with heat and urea and to inhibition by Levamisole. The possible origin of the enzyme in normal liver and its relationship to the Kasahara isoenzyme and fetal intestine-type in hepatoma is discussed.
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PMID:A novel alkaline phosphatase, a minor component of normal liver phosphatases. 20 20


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