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)

An abnormal fibrinogen in patients with liver diseases, especially liver cirrhosis and hepatocellular carcinoma was examined. In these patients, delayed polymerization of fibrin monomer, which was useful for detecting abnormal fibrinogen in plasma and also detecting one of liver dysfunctions, was observed. Same results were found by using purified abnormal fibrinogen from these patients. However, according to electrophoretic and immunochemical studies, no difference were shown between purified abnormal fibrinogen and purified normal fibrinogen. The total content of sialic acid in purified abnormal fibrinogen was markedly increased as compared to that in purified normal fibrinogen. When coagulation time was examined by using asialofibrinogen treated with neuraminidase, the prolonged coagulation time was partially normalized even in patients with liver cirrhosis. These findings suggested that sialic acid might affect the polymerization of fibrin monomer. It was reported by Harvey (1978) that an abnormal fibrinogen in liver diseases was similar to the fetal fibrinogen in the content of sialic acid and prolongation of thrombin time. Therefore, purified fibrinogen from umbilical cord blood was also investigated by similar methods. Consequently, it was suggested that a dysfunction of fibrinogen in umbilical cord blood was not related to molecular abnormality, but some inhibitory mechanisms which caused the abnormal pattern of coagulation might be existed.
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PMID:[Hemostatic studies on acquired abnormal fibrinogenemia in severe liver diseases and umbilical cord blood]. 407 19

1. Rabbit anti-(rat foetal liver) serum, absorbed with adult rat liver cells, decreased the electrophoretic mobility of foetal liver cells by 51% and rat hepatoma cells by 45%, indicating the presence of a foetal-type antigen on the hepatoma cell membrane. 2. The chemical nature of the surface antigen was investigated. Incubation with neuraminidase had no effect on adult liver cells but decreased the electrophoretic mobility of foetal liver cells by 51% and of hepatoma cells by 34%; the effect of antiserum was decreased to one-fifth. 3. Sialic acid, or the supernatant from neuraminidase-treated cells, partially blocked the decrease in electrophoretic mobility induced by antiserum. 4. The pH-electrophoretic mobility curves of hepatoma cells treated with antisera were consistent with a sialic acidcontaining antigen on the surface of the tumour cells. 5. Treatment with ribonuclease did not decrease the electrophoretic mobility of adult-liver cells, but decreased that of the foetal liver cells by 17% and hepatoma cells by 29%. 6. In parallel studies made with mouse BP8 ascites-tumour cells ribonuclease decreased the electrophoretic mobility by 39%, that of normal mouse lymph-node cells by 4.8% and allergized mouse lymph-node cells by 13.3%. 7. Trypsin treatment also decreased the electrophoretic mobility of hepatoma cells by 22%.
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PMID:A study of the cell surface of tumour, foetal and lymph-node cells by cell electrophoresis after antibody and enzymic treatment. 434 55

gamma-Glutamyltransferase was solubilized from human hepatoma tissues by bromelain treatment, and some of its properties were compared with those of the normal adult liver enzyme. An electrophoretic study showed a slightly different mobility between the two enzymes before and after neuraminidase treatment. The hepatoma tissue enzyme was distinguished from the normal liver enzyme by decreased affinity to Con A. However, the enzymes from the two sources were found to be very similar or identical with respect to molecular weight, Michaelis constant, pH optimum, thermostability, effect of various L-amino acids as acceptors, behavior to divalent cations or ethylenediaminetetraacetate, inhibition by urea or sodium dodecyl sulfate, and immunological properties. These results suggest that the hepatoma tissue gamma-glutamyltransferase is largely due to altered glycosylation of this glycoprotein in hepatoma cells.
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PMID:gamma-Glutamyltransferase from human hepatoma tissue in comparison with normal liver enzyme. 611 82

gamma-Glutamyl transpeptidases, purified from rat yolk sac tumor and AH-66 hepatoma cell lines resemble this enzyme system from rat kidney in their amino acid composition and antigenicity, but differ by having a higher carbohydrate content. The different carbohydrate contents resulted in the tumor cell and rat kidney enzymes having different molecular weights. Isoelectric focusing of the neuraminidase-treated enzymes showed that a substantial portion of the enzymes from yolk sac tumor and AH-66 cells shifted to a form with an isoelectric point at pH 7.4. However, a heterogeneous pattern was still found in the kidney enzyme even after extensive neuraminidase treatment.
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PMID:Physiochemical and immunochemical characterization of gamma-glutamyl transpeptidase from yolk sak tumor and ascitic hepatoma (AH-66) cells. 611 36

We isolated the soluble forms of gamma-glutamyltransferase (EC 2.3.2.2; gamma-GT) from adult and fetal human liver and primary hepatoma and compared their properties. The Km value for L-gamma-glutamyl-p-nitroanilide and glycylglycine, the Ki for anthglutin, and the pH optimum were identical for the enzyme from all three sources. Nor were significant differences observed among the three in their heat stability, inhibition by serine and borate, or ability to transfer the gamma-glutamyl moiety to various amino acids and dipeptides. Unlike membrane-bound gamma-GT, the soluble form from all three sources entered polyacrylamide gel and showed identical electrophoretic mobilities. Treatment with neuraminidase decreased the electrophoretic mobilities to a similar extent. The relative molecular mass of the enzyme from each of the three sources is about 84 000. Immunoinhibition and immunoprecipitation of gamma-GT from the three sources by antibody to fetal liver gamma-GT followed an identical pattern. Gamma-GT from fetal liver and hepatoma differed significantly from that of adult liver in affinity for wheat-germ agglutinin and Ricinus communis agglutinin (RCA-120). In many of the properties studied, soluble gamma-GT resembles the papain-digested form of membrane-bound gamma-GT.
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PMID:Soluble forms of gamma-glutamyltransferase in human adult liver, fetal liver, and primary hepatoma compared. 612 78

The authors discussed the clinical significance and some properties of the novel gamma-GTP isoenzyme (novel gamma-GTP) which was reported to be specific for sera of hepatocellular carcinoma (HCC) in our previous publications. One or more of specific bands (novel gamma-GTP) such as bands II, II' and I' were electrophoretically detectable in 109 (55%) of 200 patients with HCC, but only in 3% of 279 patients with other hepatobiliary diseases. Novel gamma-GTP was found in 38% of HCC patients with AFP levels below 400 ng/ml. The incidence of novel gamma-GTP was independent of the clinical stage as classified by liver scanning. Even in stage I, where filling defects were not seen, the incidence was 52%. It is concluded that novel gamma-GTP is useful in diagnosis of HCC patients with low levels of AFP or at a relatively early stage. Some properties of gamma-GTP purified from HCC tissues were investigated and compared with those of the normal kidney enzyme. The enzymes from HCC and kidney were identical in enzymatic and immunological properties, whereas a considerable difference was observed in electrophoresis, Con A affinity, effect of neuraminidase and isoelectric point. Respective bands II, II' and I' could be differentiated in Con A affinity and neuraminidase reaction. These results support the possibility that novel gamma-GTP in sera of HCC patients is largely due to a difference in carbohydrate moiety of gamma-GTPs.
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PMID:[A new tumor marker--novel gamma-GTP isoenzyme]. 613 55

In order to elucidate the characteristics of novel gamma-GTP, which was reported in our previous publications to be specific to sera of HCC, gamma-GTP was purified from HCC tissues, and its physicochemical and immunologic properties were compared with those of the normal adult kidney enzyme. The enzyme from HCC tissue and from normal kidney were found to be similar or identical with respect to the Km value for substrate, optimal pH, thermostability, effect of various amino acids as acceptors, behavior to cations or ethylendiaminetetraacetate, and immunologic properties. However, the HCC tissue enzyme was distinguishable from the normal kidney enzyme with respect to molecular weight, electrophoretic mobility before and after neuraminidase treatment, Con-A-affinity, sensitivity to neuraminidase, and isoelectrophoretic point. These results support the conceivability that novel gamma-GTP in the sera of HCC patients is largely due to structural differences in the carbohydrate moieties.
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PMID:Purification of gamma-glutamyltranspeptidase (gamma-GTP) from human hepatocellular carcinoma (HCC), and comparison of gamma-GTP with the enzyme from human kidney. 614 76

The authors discussed the clinical significance and some properties of the novel gamma-GTP isoenzyme (novel gamma-GTP) which was reported to be specific for sera of hepatocellular carcinoma (HCC) in our previous publications. One or more of specific bands (novel gamma-GTP) such as bands II, II' and I' were electrophoretically detectable in 109 (55%) of 200 patients with HCC, but only in 3% of 279 patients with other hepatobiliary diseases. Novel gamma-GTP was found in 38% of HCC patients with AFP levels below 400 ng/ml. The incidence of novel gamma-GTP was independent of the clinical stage as classified by liver scanning. Even in stage I, where filling defects were not seen, the incidence was 52%. It is concluded that novel gamma-GTP is useful in diagnosis of HCC patients with low levels of AFP or at a relatively early stage. Some properties of gamma-GTP purified from HCC tissues were investigated and compared with those of the normal kidney enzyme. The enzymes from HCC and kidney were identical in enzymatic and immunological properties, whereas a considerable difference was observed in electrophoresis, Con A affinity, effect of neuraminidase and isoelectric point. Respective bands II, II' and I' could be differentiated in Con A affinity and neuraminidase reaction. These results support the possibility that novel gamma-GTP in sera of HCC patients is largely due to a difference in carbohydrate moiety of gamma-GTPs.
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PMID:[Novel gamma-GTP isoenzyme and hepatocellular carcinoma]. 614 31

This paper reports the isolation and characterization of a soluble antigen shared by the liver and kidney of human and some other animal species. Homogenates of human liver in saline were centrifugated at 27,000 g and the supernatants were fractionated by preparative polyacrylamide gel electrophoresis. The gels were divided in sections and each was injected into rabbits; after absorption with polymerized normal human serum, the antiserum obtained by injecting one of the sections reacted only with saline extracts of human liver and kidney when tested against a variety of human tissue extracts. The absorbed antiserum, polymerized and insolubilized with glutaraldehyde, was used to purify the antigen by affinity chromatography. The purified antigen proved to be a glycoprotein containing 19 percent carbohydrate, had a molecular weight of 5.8-6.0 x 10(4) Daltons and a pI of 7.2-7.4. The antigen, relatively thermostable, was precipitated by 35-55 percent ammonium sulphate; its antigenic activity was not affected by extraction with 0.6 N perchloric acid or by incubation with ribonuclease, deoxyribonuclease or neuraminidase but was destroyed by incubation with ttypsin or chymotrypsin. Immunoperoxidase studies showed that the antigen appeared concentrated in the neclei of liver and kidney glomerular epithelial and tubular epithelial cells in humans and rats. The antigen could not be detected in human hepatomas or hypernephromas or in the rat Morris hepatoma 5123.
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PMID:Isolation and characterization of a human liver and kidney-specific protein: the hepato-renal (H-R) antigen. 615 31

Goat antibodies directed against a subset of the externally oriented plasma membrane glycoproteins of hepatoma tissue culture (HTC) cells were used to follow the metabolic fate of the membrane antigens and the specifically bound immunoglobulin molecules in this cell type in cultures. Analyses of the immunoprecipitates from cells labeled in situ with neuraminidase and galactose oxidase, followed by reduction with tritiated sodium borohydride, indicate that about 40% of the galactose-labeled plasma membrane glycoproteins are recognized by the antiserum. Fluorescent microscopic analyses of cells treated with fluorescein-conjugated immunoglobulins and analyses of trypsin accessibility indicate that probably all of the antibodies bound to the cell surface are patched and internalized within about 4 hr when the cells are subsequently cultured at 37 degrees C in the presence of rabbit anti-goat immunoglobulins. At the same time, the antigens are also interiorized. Analyses of the cellular localization of the interiorized antigens and antibodies by cell fractionation on Percoll gradients show that the immunoglobulins to the cell surface antigens and the antigens themselves migrate to the same region of the Percoll gradient as lysosomal hydrolases. Although the antibodies bind to the cell surface glycoproteins and bring about patching and interiorization, there is no effect on the degradation of the plasma membrane antigens labeled via the galactose oxidase/borohydride reduction method. Furthermore, the iodinated antibodies directed against these membrane glycoproteins behave in their turnover properties like membrane antigens; the cell-bound specific immunoglobulins have the same half-life as the membrane glycoproteins. When the cells that had been reacted with the goat antibodies to membrane glycoprotein were cultured in the presence of rabbit anti-goat immunoglobulins, degradation of the former antibodies was effectively decreased. Similar results were obtained with concanavalin A and antibodies directed against this plant lectin.
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PMID:Metabolic fate of cell surface glycoproteins during immunoglobulin-induced internalization. 625 73


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