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)

Since cell adhesiveness is very important in the metastatic process and because both hyperthermia and treatment with Retinol can modify the fluidity of the lipid components of the plasma membrane (and therefore its receptor distribution), we investigated if a hyperthermic treatment (at 42 degrees C or 44 degrees C, for one hour) of HTC hepatoma cells, preceded or followed by treatment with 5 microM Retinol, could alter cell adhesiveness to Laminin or to Fibronectin-coated substrata. Hepatoma cells, after such treatments, were collected and processed by Auerbach's method. In the control cells thermal treatment alone caused a decrease of adhesiveness to Laminin but no change in that to Fibronectin. When treatment with Retinol was carried out before hyperthermia, the cells showed an increased adhesiveness to Laminin and a decreased adhesiveness to Fibronectin. Instead, when treatment with Retinol was performed in cells previously thermo-selected, a decrease of adhesiveness to both tested ligands was observed.
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PMID:[Effect of hyperthermia and retinol treatment in vitro on HTC cell adhesiveness to laminin and fibronectin]. 130 26

Many tests for hepatitis C virus (HCV) infection have been developed and have proved useful for prevention of post-blood transfusion hepatitis C. However, there are at least 4 genotypes of HCV and the predominant type is different among countries. None of the tests using antigens from one genotype are sensitive in detecting the antibodies against another genotype. More sensitive tests using a more stable part of the HCV RNA sequences such as 5'-noncoding region must be developed for clinical use. Automated PCR methods and DNA sandwich hybridization methods using branched DNA amplification multimers may be candidates. Recently a hepatocyte growth factor test has been developed in Japan. Multicenter trials of this test reveal that it is useful for assessment of acute severe hepatitis. Tests for collagen type IV, fibronectin receptor, and prolyl hydroxylase have been reported useful for assessment of liver fibrosis. However, serum prolyl hydroxylase is prone to increase in response to hepatocellular damage as well as fibrotic processes. Enzymatic methods for determination of branched amino acids and tyrosine have been developed. The molar ratio of branched amino acids to tyrosine seems to have same pathophysiological meaning as the ratio of branched amino acids to aromatic amino acids (Fischer ratio) in assessment of liver cirrhosis. Lidocaine test is reported to be useful for predicting survival of transplanted liver and also assessing the function of the cirrhotic liver. Profiles of alpha-fetoprotein subfractions based on lectin-reactivity and galactosyl transferase II isoenzyme have been reported to be useful for detecting hepatocellular carcinoma but this remains to be proved.
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PMID:[Recent advances in laboratory tests for liver diseases]. 130 30

The effects of fibronectin (FN) on cytodifferentiation and cell cycle in a human hepatoma cell line QGY-7703 were studied by flow cytometry, electron microscopy, etc. The results indicated that FN inhibited cell proliferation and mitosis; significant differences were noted between the control group and the experimental group (P < 0.01). FN blocked the cell cycle in phase S; cell spreading improved with less cell overlapping, and the growth of monolayer cell was partially restored. The number of microvilli and marginal ruffles decreased and that of mitochondria, Golgi complex, endoplasmic reticulum increased. The findings suggested that FN could partially restore QGY-7703 cell normal phenotype and probably be useful for the treatment of tumor.
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PMID:[Effects of fibronectin on cytodifferentiation and cell cycle in a human hepatoma cell line QGY-7703]. 133 92

Tenascin is an oligomeric glycoprotein of the extracellular matrix synthesized during embryonic development. It is prominently expressed in a variety of tumors. The role of tenascin in liver tissue is, however, unknown. We used immunocytochemistry to define the localization of tenascin and compare this with the localization of non-collagenous proteins, such as laminin and fibronectin, in normal human liver and pathological liver from patients with chronic hepatitis, liver cirrhosis and hepatocellular carcinoma. In normal liver, tenascin expression was localized along the sinusoidal and vascular wall. In fibrotic liver, tenascin was also observed in the region between the hepatic parenchyma and the fibrosing portal tracts, especially in areas of piecemeal necrosis in chronic hepatitis. Immuno-EM study of liver tissue in chronic hepatitis strongly suggested the synthesis and secretion of tenascin by fat-storing cells into the space of Disse. In hepatocellular carcinoma, tenascin was expressed in both the capsule and lobular septa, but not in the sinusoidal walls of the tumors. These results led us to postulate a close relationship between the occurrence of this protein and disease processes such as fibrosis and cancer invasion.
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PMID:Tenascin expression in human chronic liver disease and in hepatocellular carcinoma. 137 63

Cells of an adherent subline (74AD, adhesion greater than 95%) and a floating subline (74FL, adhesion less than 1%) of rat ascites hepatoma AH7974 produced substrates containing fibronectin (FN), laminin (LN) and type IV collagen (CL-IV), with 74AD cells producing higher levels of each component. 74AD cells possessed high adhesion affinities to LN and CL-IV substrates. By contrast, 74FL cells hardly adhered to these purified attachment proteins. The difference in adhesion between the two lines in vitro tended to increase on incubation of the cells in medium containing fetal bovine serum. However, 74FL and 74AD cells adhered avidly to the extracellular matrix (ECM) of vascular endothelial cells. Although the cell-ECM adhesion apparently was not inhibited by pretreatment of the ECM with anti-FN, anti-LN and anti-CL-IV antibodies, the 74FL cell-ECM adhesion was inhibited considerably by pretreatment of the ECM with a mixture of these antibodies, especially with a combination of anti-FN and anti-LN antibodies. The lung-colonizing potential of 74FL cells was greater than that of 74AD cells, but the liver-colonizing potential of 74FL cells was less than that of 74AD cells. These results suggest that rat ascites hepatoma cells with extremely reduced substrate adhesiveness retain an adhesion mechanism that binds to FN and LN in the ECM of vascular endothelial cells. This mechanism may be a minimum essential unit of tumor cell-ECM adhesion in lung colonization, but the unit is insufficient for liver colonization of these cells.
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PMID:Substrate adhesiveness and experimental metastatic potential of rat ascites hepatoma AH7974-derived variant sublines. 137 14

The extracellular matrix adhesion molecule fibronectin exhibits different isoforms derived by alternative splicing as well as recently demonstrated variation in O-glycosylation. Although fibronectin is widely distributed in normal tissues, the individual isoforms have been found to show restricted tissue distribution and association with malignancies. The monoclonal antibody FDC-6 defines a cancer-associated de novo glycosylation of a specific threonine residue in the C-terminal region of the fibronectin molecule termed oncofetal fibronectin. Here we report an immunohistological study of oral squamous cell carcinomas (n = 33), premalignant lesions (n = 15), and normal oral mucosa (n = 10) using the FDC-6 antibody. A selective expression of the oncofetal fibronectin epitope was demonstrated in close relation to the invading carcinoma, whereas no staining was observed in premalignant lesions without epithelial dysplasia, or in normal epithelium. Furthermore, we attempted to identify additional carbohydrate-related epitopes distinguishing fibronectin of human hepatoma cell line HUH-7 from plasma fibronectin. No novel epitopes were identified, as all generated monoclonal antibodies lacking reactivity with plasma fibronectin showed the same specificity as FDC-6. Previous studies have indicated that the de novo glycosylation is induced by a novel transferase activity only found in fetal and carcinoma cell lines, placenta and hepatoma tissues. Here we provide further evidence that a purified UDP-GalNAc:peptide N-acetylgalactosaminyltransferase from normal bovine thymus and human placentae is incapable of utilizing the hexapeptide VTHPGY as a substrate. The results demonstrate that oncofetal fibronectin is highly associated with malignancy, and appears to be induced by expression of a unique glycosyltransferase or modification of the specificity of the normally expressed transferase.
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PMID:Cancer-associated changes in glycosylation of fibronectin. Immunohistological localization of oncofetal fibronectin defined by monoclonal antibodies. 138

The dynamic changes of fibronectin (FN) content and nuclear features (DNA content, morphological parameters) during the development of hepatoma induced by 3'-Me-DAB were studied via computer-assisted image analysis. The results showed that the amount of FN decreased progressively and even disappeared completely during hepatocarcinogenesis. The difference between distinctive foci or nodules was highly significant (P less than 0.0001) and the DNA content was also increased coincidently during the same process.
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PMID:[Dynamic changes of fibronectin, DNA and morphology of the nuclei of experimental hepatoma in rats]. 149 77

The synthesis and secretion of fibronectin (FN) was observed in 4 human hepatocellular carcinoma (HCC)-derived cell lines using a serum-free conditioned medium. It was also demonstrated that FNs secreted from these cell lines (HCC-FN) were structurally altered compared to plasma FN produced by normal hepatocytes. Using limited proteolysis with cathepsin D followed by immunoblot analysis with a carboxy-terminal specific antibody, the existence of an extra domain (ED) segment in the carboxy-terminal region of HCC-FNs was confirmed. Expression of the additional nucleotide insert (ED sequence), which is reported to be absent in hepatocyte mRNA and is characteristic of cellular FN-mRNA, was confirmed in mRNA from all 4 HCC cell lines. It is now evident that HCC cells secrete different variants of FN compared with normal hepatocytes due to alternative splicing of mRNA precursors. This differential RNA processing seems to be one of the phenotypic alterations associated with the oncogenic transformation of hepatocytes.
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PMID:Structural alterations in fibronectins secreted from 4 human hepatoma cell lines: demonstration of hepatoma-associated alternative splicing of mRNA precursors. 166 73

Vitronectin (VN), fibronectin (FN) and laminin (LM), which are known to be important glycoproteins in cell attachment, are produced by such liver cells as hepatocytes, Kupffer cells endothelial cells and Ito cells. In this study, the levels of plasma VN, FN and serum LM P1 in patients with chronic hepatitis, liver cirrhosis and hepatocellular carcinoma accompanied with cirrhosis were examined and compared with those in normal subjects. Plasma VN levels in patients with chronic hepatitis, compensated cirrhosis and decompensated cirrhosis were less than that in normal subjects. As hepatic dysfunction deteriorated, plasma VN level decreased in chronic liver diseases. Plasma FN levels in patients with compensated and decompensated cirrhosis were also less than that of patients with chronic hepatitis, which was not significantly different from that of normal subjects. Plasma VN and FN levels in patients with hepatocellular carcinoma were similar to those in patients with compensated cirrhosis. Plasma VN and FN levels in patients with chronic liver diseases including hepatocellular carcinoma showed positive correlations with serum albumin content, cholinesterase activity, and normalized normo test value. On the other hand, serum LM P1 levels in patients with chronic hepatitis, compensated cirrhosis and decompensated cirrhosis were higher than that of normal subjects. As hepatic dysfunction deteriorated, serum LM P1 level increased in chronic liver diseases. Level of serum type IV collagen 7S, which is related to hepatic fibrosis, was similar to that of serum LM P1; serum LM P1 concentration in patients with chronic liver diseases showed a significant positive correlation with that of serum type IV collagen 7S. Immunolocalization of VN in liver tissue from patients with chronic hepatitis and cirrhosis was examined by the method of avidin-biotin-complex staining, and positive reaction was observed in enlarged portal tracts, central veins and fibrous septa. These results suggest that decreased levels of plasma VN and FN and increased level of serum LM P1 in patients with chronic liver diseases are related to hepatic dysfunction, and that changes in the levels of these glycoproteins involved in cell attachment are important in the development of hepatic fibrosis in patients with chronic liver diseases.
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PMID:[Changes in plasma vitronectin, fibronectin, and serum laminin P1 levels and immunohistochemical study of vitronectin in the liver of patients with chronic liver diseases]. 170 42

Cell interactions with the extracellular matrix are consistently modified in neoplasia. Malignant transformation has been correlated with modifications in the synthesis and distribution of matrix components and with alterations of cell adhesive properties to these components. A particular class of genes, able to suppress the transformed phenotype in normal cells, may be involved in those phenotypic changes. By studying somatic cell hybrids between mouse hepatoma (BWTG3) cells and normal rat skin fibroblasts (RSF), Islam and co-workers were able to localize a gene or a group of genes controlling anchorage dependence and cell growth in vitro. This (or these) gene(s) was (were) assigned to the q22-23 fragment of rat chromosome 5. In the present study, we compare the morphology and the interactions with the extracellular matrix proteins (laminin, fibronectin, and collagen IV) and the synthesis of these proteins by RSF X BWTG3 hybrid cells that had either retained (BS181p10) or lost (BS181a5) the q22-23 region of rat chromosome 5. Our results suggest that the rat 5q22-23 fragment controls a part of the cell differentiation program including morphology, attachment to extracellular matrix, and synthesis of some matrix proteins, particularly alpha 1 and alpha 2 chains of collagen IV.
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PMID:Rat chromosome 5 (q22-23) contains elements that control cell morphology and interactions with the extracellular matrix: a study of normal fibroblast x malignant hepatoma cell hybrids. 171 82


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