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Query: UMLS:C0019204 (hepatocellular carcinoma)
 71,386 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Among the patients with liver cirrhosis (LC) who undergo the operation, the postoperative complications are not infrequent and sometimes prove fatal. The impaired hepatic function, especially the impaired reticuloendothelial system (RES) function, has been claimed to be a possible pathogenic factor for these complications. The present experimental and clinical studies were undertaken to investigate the RES function and the effect of preoperative OK-432 administration as an RES potentiator in LC. The results are as follows: 1) CCl4-induced LC rats were evaluated for RES global phagocytic function, Kupffer cell phagocytic function, plasma opsonic activity and plasma opsonic substances such as fibronectin, C3 and IgG. All parameters except IgG showed significant depression compared to those values in normal rats. However, the administration of OK-432 (0.1 KE/rat, ip) improved all these depressed parameters. The OK-432 administration also significantly improved the survival following panperitonitis in LC rats. 2) Among 18 LC patients with hepatocellular carcinoma undergoing partial hepatectomy, the RES global phagocytic function, plasma opsonic activity and plasma opsonic substances were evaluated. Same as the experimental study, all parameters except IgG were significantly depressed among the LC patients compared to those values in the patients with normal liver. However, the preoperative OK-432 administration (5 KE/day sc for 4 days) significantly improved these parameters and consequently decreased the postoperative complications. These results indicate that the preoperative RES activation by the OK-432 was effective and useful for the prevention of the postoperative complications in the LC patients.
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PMID:[Experimental and clinical studies on the effect of reticuloendothelial system (RES) potentiator in the depressed RES function in cirrhotics]. 362 94

Retinoids enhanced adhesion of spontaneously-transformed mouse fibroblasts to the substrate of culture in a reversible way. They also caused an increase in the incorporation of radioactively-labeled mannose into 'complex type' oligosaccharides of glycopeptides isolated from the cell surface. Consistent with this response was a similar increase in 'complex type' oligosaccharide chains from the collagen binding domain of fibronectin from retinoid-treated, more adhesive rat sternal chondrocytes. Tumor promoting phorbol esters caused a decrease in adhesion and the shedding of fibronectin from the cell surface. Opposing actions of tumor promoting agents and retinoids exist at the level of expression of squamoid metaplasia of the respiratory tract. Both hepatomas with minimal and a maximal growth rate contained less retinyl palmitate than host liver. Similarly, the level of the cellular retinol binding protein (CRBP) was greatly reduced in the hepatoma tissue. Considerations on the antagonistic actions of tumor promoters and retinoids, the phenotype of squamous cell carcinomas of the bronchus and the vitamin A deficient status of hepatoma tissue suggested the following concepts: compounds which perform essential functions (e.g. vitamin A) may prevent initiated cells from expressing the tumorigenic phenotype; tumor promoters may act by interfering either directly or indirectly with the essential function of these compounds; normal cells respond to deficiency of essential function by differentiation and/or cell death; and initiated cells express the new phenotype, have a growth advantage and become self-sufficient.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Retinoids and tumorigenesis: mechanistic considerations. 406 4

Transglutaminase activity was reduced in malignant hepatoma, virus-transformed human and hamster cells, and chemically transformed mouse cells when compared to normal counterparts. The reduction in enzyme activity reflected the presence of fewer transglutaminase molecules in transformed cells. Greater amounts of the enzyme activity were particulate-associated in confluent and arrested normal human cells. Indirect immunofluorescence studies with antibody to cellular transglutaminase demonstrated the presence of transglutaminase in Triton X-100-insoluble material. A parallel between pericellular fibronectin and transglutaminase (TGase) was demonstrated. Normal human and mouse cells that elicited contact inhibition of growth and had the high TGase activity also had more epsilon-(gamma-glutamyl) lysine isopeptide bonds than transformed counterparts. Similarly nonproliferating human cells had higher transglutaminase activity and isopeptide levels than did proliferating populations. These results suggest that isopeptide bond formation stabilizes the cell membrane and contributes to a nonproliferating state. Inhibition of isopeptide formation should therefore lead to a mitogenic response. Preliminary results support such a relationship. A model depicting control of isopeptide formation at either enzyme or substrate level is presented.
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PMID:Transglutaminase and epsilon-(gamma-glutamyl) lysine isopeptide bonds in eukaryotic cells. 610 9

A rat hepatoma cell line was shown to synthesize heparan sulfate and chondroitin sulfate proteoglycans. Unlike cultured hepatocytes, the hepatoma cells did not deposit these proteoglycans into an extracellular matrix, and most of the newly synthesized heparan sulfate proteoglycans were secreted into the culture medium. Heparan sulfate proteoglycans were also found associated with the cell surface. These proteoglycans could be solubilized by mild trypsin or detergent treatment of the cells but could not be displaced from the cells by incubation with heparin. The detergent-solubilized heparan sulfate proteoglycan had a hydrophobic segment that enabled it to bind to octyl-Sepharose. This segment could conceivably anchor the molecule in the lipid interior of the plasma membrane. The size of the hepatoma heparan sulfate proteoglycans was similar to that of proteoglycans isolated from rat liver microsomes or from primary cultures of rat hepatocytes. Ion-exchange chromatography on DEAE-Sephacel indicated that the hepatoma heparan sulfate proteoglycans had a lower average charge density than the rat liver heparan sulfate proteoglycans. The lower charge density of the hepatoma heparan sulfate can be largely attributed to a reduced number of N-sulfated glucosamine units in the polysaccharide chain compared with that of rat liver heparan sulfate. Hepatoma heparan sulfate proteoglycans purified from the culture medium had a considerably lower affinity for fibronectin-Sepharose compared with that of rat liver heparan sulfate proteoglycans. Furthermore, the hepatoma proteoglycan did not bind to the neoplastic cells, whereas heparan sulfate from normal rat liver bound to the hepatoma cells in a time-dependent reaction. The possible consequences of the reduced sulfation of the heparan sulfate proteoglycan produced by the hepatoma cells are discussed in terms of the postulated roles of heparan sulfate in the regulation of cell growth and extracellular matrix formation.
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PMID:Structure and properties of an under-sulfated heparan sulfate proteoglycan synthesized by a rat hepatoma cell line. 623 Mar 67

This paper describes the isolation and partial characterization of a collagen cell attachment protein from the spent culture medium of rat hepatoma cells. When compared with serum fibronectin, this attachment protein differed in several biochemical parameters. The hepatoma attachment protein was partially purified by adsorbing and eluting from an inorganic gel, magnesium oxide. Cell adhesive activity may routinely recovered at levels of 10 to 30%, and a 2000-fold purification was attained. The hepatoma attachment protein was shown to be sensitive to trypsin and chymotrypsin, to be heat inactivated at 61 degrees, to have a molecular weight of 58,000, to have an isoelectric point of 4.1, to show an electrophoretic mobility on cellulose acetate of approximately one-half that of fibronectin, and not to cross-react with antifibronectin antisera.
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PMID:Collagen cell attachment protein from rat hepatoma cells. 626 32

A human hepatoma cell line, HuH-7, which was established from a hepatocellular carcinoma, was found to replicate continuously in a chemically defined medium when the medium was supplemented with Na2SeO3. The cells grew better in this medium than in serum-containing medium without any adaptation period. Other established human hepatoma and hepatoblastoma cell lines, HuH-6 cl-5, PLC/PRF/5, huH-1, and huH-4, also grew in the defined medium. Although HLEC-1 cells failed to proliferate continuously with Na2SeO3 alone, they grew if a cell-free conditioned medium from HuH-7 cells was added to the medium. These cell lines, except the HLEC-1 cell line, produced the following human plasma proteins among those examined: albumin, prealbumin, alpha 1-antitrypsin, ceruloplasmin, fibrinogen, fibronectin, haptoglobin, hemopexin, beta-lipoprotein, alpha 2-macroglobulin, beta 2-microglobulin, transferrin, lipoprotein, alpha 2-macroglobulin, beta 2-microglobulin, transferrin, Complement Components 3 and 4, and alpha 1-fetoprotein. Beside plasma proteins, the media from HuH-7, HuH-6 cl-5, PLC/PRF/5, and huH-1 contained anti-carcinoembryonic antigen-reactive proteins, and those from PLC/PRF/5, huH-1, and huH-4 medium contained hepatitis B surface antigen. These proteins were detected during periods of serial cultivation over 9 months under the above culture conditions. The hepatoma cell lines grown in the fully defined synthetic medium may provide a new approach for investigating the growth and metabolism of human hepatoma cells in vitro.
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PMID:Growth of human hepatoma cells lines with differentiated functions in chemically defined medium. 628 15

The tumor promoter teleocidin inhibited the proliferation of human HUH hepatoma cells in tissue culture. HUH cells cultured with teleocidin developed elongated cytoplasm. In addition, these biological effects of teleocidin were associated with a remarkable decrease in the amount of cellular fibronectin. The synthesis of structural proteins and the number of cell surface receptors for epidermal growth factor were not altered in cells treated with teleocidin, suggesting that teleocidin acted selectively on some of the cellular constituents such as fibronectin. The present data also suggest a possible relationship between the cellular fibronectin content and the biological characters of HUH cells.
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PMID:Effects of the tumor promoter teleocidin on human hepatoma cells in tissue culture. 629 66

Human liver specimens with hepatocellular carcinoma were studied for distribution of fibronectin by immunofluorescence staining. Fibronectin was detected in the cytoplasm and/or on the cell surface in certain cases, which is in contrast to the observations in vivo for hepatocytes of normal and other fibrotic livers. The present finding is also in contrast to those for various other carcinomas so far reported.
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PMID:Fibronectin in human hepatocellular carcinoma. 629 70

When the hepatoma cells (AH 70Btc, Clone 10-5) were cultured in the presence of 1 mM-dibutyryl cyclic AMP for 2 days, the incorporation of [14C]glucosamine into protein was increased over 2-fold. At the same time, dibutyryl cyclic AMP increased the incorporation of [14C]glucosamine into dolichol-linked N-acetylglucosamine and NN'-diacetylchitobiose about 1.5-fold and into dolichol-linked oligosaccharides about 3-fold. Analysis of cellular glycoproteins by sodium dodecyl sulphate/polyacrylamide-gel electrophoresis after reduction showed that dibutyryl cyclic AMP specifically enhanced the glycosylation of a fibronectin-like glycoprotein with an apparent mol.wt. of 220 000 and two other high-molecular-weight glycoproteins (apparent mol.wts. 270 000 and 185 000). Increased glycosylation of the glycoproteins with mol.wts. of 220 000 and 185 000 was shown to be linked to increased synthesis of the polypeptide portion. In addition to the above effects, dibutyryl cyclic AMP enhanced the adhesiveness of AH 70Btc cells to glass surfaces. Both the effects on the glycosylation pathway and on adhesiveness of cells were reversed by further treatment of the cells with 1 microgram of tunicamycin/ml. The results indicated that dibutyryl cyclic AMP increased the synthesis of dolichol-linked oligosaccharides and N-glycosylation of proteins in AH 70Btc cells. The enhancement of adhesiveness may be mediated by the increased synthesis of dolichol-linked oligosaccharides and also may be related to the increased synthesis of fibronectin.
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PMID:Effects of dibutyryl cyclic AMP on the syntheses of dolichol-linked saccharides and glycoproteins in cultured hepatoma cells. Correlation with the effect on the adhesiveness of the cells. 630 56

Fibronectin is a family of immunologically similar glycoproteins which mediate a variety of cell-cell and cell-substratum interactions. It is a constituent of the extracellular matrix of connective tissue and circulates in plasma. When suspension and adherent cultures of a human hepatoma cell line (SK-HEP-1) were incubated in serum-free medium, the resulting conditioned medium contained material which was specifically immunoprecipitated by antisera to human plasma fibronectin. By double immunodiffusion, a component in the conditioned culture medium was shown to form a line of identity with fibronectin in human plasma and to migrate as an alpha 2- to beta-globulin during immunoelectrophoresis. Human fibronectin was quantified in conditioned medium by electroimmunodiffusion, and was found to increase for at least three days at about 0.1 micrograms/10(6) cells/day. Adherent cultures of SK-HEP-1 cells were incubated with L-[35S]methionine to label newly synthesized proteins. Labeled fibronectin in conditioned medium or in cell extracts comigrated with fibronectin in human plasma as shown by autoradiography following crossed-immunoelectrophoresis. Fibronectin was demonstrated in the extra-cellular matrix of adherent SK-HEP-1 cultures by immunofluorescence. We had shown previously that SK-HEP-1 cells synthesize alpha 1-protease inhibitor, one of the products of normal hepatocytes. The finding that these hepatoma cells also synthesize fibronectin supports the concept that the hepatocyte may be one source of circulating fibronectin, a possibility consistent with the established role of this cell type in blood plasma protein synthesis.
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PMID:Fibronectin synthesized by a human hepatoma cell line. 632 32


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