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)

Monoclonal antibodies were used in one step sandwich enzyme immunoassay (one step sandwich EIA) for human serum immunoreactive type IV collagen. The one step sandwich EIA using either polystyrene ball or microplate was characterized by carrying out two immunoreactions simultaneously, type IV collagen reacting with both a monoclonal antibody as a solid phase and a horseradish peroxidase-labeled monoclonal antibody (Fab') against human type IV collagen as a conjugate. Sensitivity of one step sandwich EIA system by using either polystyrene ball or microplate was 0.22 ng per tube or 0.04 ng per well for type IV collagen, and linearity was obtained between 0.22-40 ng/tube or 0.04-20 ng per well, respectively. Both methods gave reproducible quantitative analysis of immunoreactive type IV collagen levels in the sera of patients with hepatocellular carcinoma and patients with liver cirrhosis, which were apparently higher than the levels in the sera of healthy subjects. Protein immunoblotting shows that the immunoreactive type IV collagen trapped in our present one step sandwich EIA system was not the 7-S and NC1 domains of type IV collagen.
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PMID:One step sandwich enzyme immunoassay for human type IV collagen using monoclonal antibodies. 254 37

Hepatocellular carcinoma (HCC) possessed the ability of vascular invasiveness toward hepatic portal vein on the process of progression. This biological character of HCC can influence the patients survival on clinically. In this paper, we tried to establish the in vitro portal invasion model with human materials. The hepatic portal vein endothelial cell (HPVEC) derived from intrahepatic portal veins by surgically, have been propagated, as outgrowth cultures in RPMI-1640 medium with 10% fetal bovine serum, on permeable collagen membranes (KOKEN, Tokyo) containing mainly type I collagen, covered with a solubilized tissue basement membrane (MATRIGEL, Collaborate Res., Inc., Bedford MA) involving type IV collagen, laminin and proteoglycan. The primary cultured HPVEC with polygonal shaped cells forming a pavement stone sheet, were positively stained with Factor VIII related antigen and synthesized both prostacyclin and collagenase inhibitor. Co-culture of primary human HPVEC and HuH-7 (human HCC cell line obtained from Prof. Satoh, Okayama Univ.,) cells were inoculated onto reverse side between collagen membrane and gell formed basement membrane. Morphological alterations on the side of HPVEC can be obtained such as polylayered cells and different cytoplasmic cells among HPVEC. These results indicate that this experimental model can provide an useful in vitro model for the study of HCC portal invasion.
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PMID:[An attempt of in vitro portal invasion model of hepatocellular carcinoma utilizing permeable collagen membrane]. 256 88

Basic fibroblast growth factor (FGF) is synthesized as a phosphoprotein by both bovine capillary endothelial and human hepatoma cells in culture. Because basic FGF is characterized by its high affinity for heparin and its association in vivo with the extracellular matrix, we examined the possibility that the phosphorylation of this growth factor by purified protein kinase C (PK-C) and the catalytic subunit of cAMP-dependent protein kinase-A (PK-A) can be modulated by components of the extracellular matrix. Heparin and other glycosaminoglycans (GAGs) inhibit the ability of PK-C to phosphorylate basic FGF. In contrast, heparin can directly increase the phosphorylation of basic FGF by PK-A. While fibronectin, laminin, and collagen IV have no effect on the ability of PK-C to phosphorylate basic FGF, they all can inhibit the effects of PK-A. Thus, there is a differential effect of extracellular matrix-derived proteins and GAGs on the phosphorylation of basic FGF. The enhanced phosphorylation of basic FGF that is mediated by heparin is associated with a change in the kinetics of the reaction and the identity of the amino acid targeted by this enzyme. The amino acids that are targeted by PK-C and PK-A have been identified by phosphopeptide analyses as Ser64 and Thr112, respectively. In the presence of heparin, basic FGF is no longer phosphorylated by PK-A at the usual PK-A consensus site (Thr112), but instead is phosphorylated at the canonical PK-C site (Ser64). Accordingly, heparin inhibits the phosphorylation of basic FGF by PK-C presumably by masking the PK-C dependent consensus sequence surrounding Ser64. Thus, when basic FGF is no longer phosphorylated by PK-A in the receptor binding domain (Thr112), it loses the increased receptor binding ability that characterizes PK-A phosphorylated basic FGF. The results presented here demonstrate three novel features of basic FGF. First, they identify a functional effect of the binding of heparin to basic FGF. Second, they establish that the binding of heparin to basic FGF can induce structural changes that alter the substrate specificity of protein kinases. Third, and perhaps most important, the results demonstrate the existence of a novel interaction between basic FGF, fibronectin, and laminin. Although the physiological significance of this phosphorylation is not known, these results clearly suggest that the biological activities of basic FGF are regulated by a complex array of biochemical interactions with the proteins, proteoglycans, and glycosaminoglycans present in the extracellular milieu and the cytoplasm.
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PMID:Differential effects of heparin, fibronectin, and laminin on the phosphorylation of basic fibroblast growth factor by protein kinase C and the catalytic subunit of protein kinase A. 259 18

By a combination of high-performance affinity chromatographic (HPAC) methods, several membrane proteins from liver, Morris hepatoma and kidney were isolated. The use of a tandem system, consisting of a concanavalin A (ConA) and a wheat germ agglutinin (WGA) high-performance liquid chromatographic (HPLC) column, as a first purification step allowed the isolation of proteins directly from organ homogenates. In a subsequent step, the membrane proteins can be isolated by simply using a combination of immunoaffinity HPLC and preparative sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE). However, with these methods most proteins lose their biological activity. If native proteins are required, a combination of different HPAC methods has to be applied. Several membrane proteins were isolated in milligram amounts under non-denaturing conditions using either HPAC columns or Mem Sep membranes with immobilized lectins, collagen, amino acids, crown ethers or heparin.
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PMID:Preparative isolation of glycoproteins from plasma membranes of different rat organs. 261 91

alpha 1-Antitrypsin (alpha 1-AT) is considered a typical plasma protein and a prototype of the serine proteinase inhibitor (serpin) family. It is synthesized in hepatocytes and, to a lesser extent, in macrophages. In this study we show that the alpha 1-AT gene is also expressed in human intestine and in a human colonic epithelial tumor cell line, Caco2. A single 1.6-kilobase alpha 1-AT-specific mRNA is present in jejunum and in Caco2 cells. It is identical in apparent size to that present in human hepatoma HepG2 cells but slightly smaller than that present in human macrophages, cells in which an alternative upstream transcriptional start site is used. Synthesis and secretion of alpha 1-AT in Caco2 cells is similar to that in HepG2 cells. It is synthesized as an approximately 52-kDa precursor polypeptide, converted to its mature, fully glycosylated 55-kDa form intracellularly, and the native protein is secreted with a half-time of 37 min. Functionally active alpha 1-AT is secreted into the basolateral and apical (luminal) fluid in pulse-chase labeling experiments of Caco2 cells cultured in polarized orientation on collagen-coated nitrocellulose membranes. Expression of alpha 1-AT in Caco2 enterocytes is not affected by soluble factors that regulate expression of alpha 1-AT in macrophages and hepatocytes. However, expression of alpha 1-AT increases markedly in Caco2 cells as they differentiate into enteric villous-type cells.
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PMID:The alpha 1-antitrypsin gene is expressed in a human intestinal epithelial cell line. 278 94

Hepatocellular carcinomas, cholangiocellular carcinomas, and "indeterminate" forms have been studied by immunohistochemical detection of several antigens: alpha-fetoprotein and CEA, as well as type IV collagen, laminin, and keratin. While the first two antigens were variably detectable in different samples, in the poorly differentiated areas of hepatocellular carcinoma type IV collagen and laminin were both absent. These basement membrane glycoproteins constantly surrounded the cholangiocellular carcinoma tubular structures and were always present in those areas of the "indeterminate" group where the cells were organized as pseudoglandular or ductular aggregates. Keratin was absent in all cases of hepatocellular carcinoma, was variably detectable in the "indeterminate" neoplasms and was always present in cholangiocellular tumors. The neoplasias with mixed histopathological features usually showed morphological and biochemical biliary differentiation at the periphery, in contact with the collagenous stroma. We postulate that in some cases hepatocarcinoma cells undergo metaplastic transformation giving rise to cholangiocellular forms. Type IV collagen, laminin, and keratin seem to be accurate markers of phenotypical differentiation and show that a continuous phenotypical spectrum exists between hepatocellular and cholangiocellular entities.
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PMID:Primary liver cell carcinoma. New insight for a more correct approach to its classification. 282 Jan 84

The identification and characterization of collagenous and non-collagenous glycoproteins have made it possible to use specific antibodies as tools for the topographical localization of the various connective tissue components, and thus to follow the progression of parenchymal-stromal interactions. This investigation is an approach to the study of in vivo relationships between basement membrane components (type IV collagen, laminin) and neoplastic cells of hepatocellular carcinoma. Ten cases of hepatic carcinomas were analysed and paraffin-embedded sections were immunostained with anti-laminin and anti-type IV collagen antibodies. The avidin-biotin-peroxidase complex technique was used. In well differentiated neoplasms with hepatic tumour cells organized in a trabecular pattern lined by sinusoid structures, type IV collagen was always detected at the sinusoidal level. Laminin was evident only in two cases with a prominent intraparenchymal vascular bed. In less differentiated neoplasms, sinusoids were almost absent and only large tumour vessels were positive for both laminin and type IV collagen. At the interface between tumour tissue and the surrounding stroma, some carcinomatous elements were surrounded by laminin and type IV collagen. Our data further support the hypothesis that basement membrane phenotypic expression may be influenced both by the degree of tumour differentiation and by the characteristics of the micro-environment.
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PMID:Hepatocellular carcinoma: expression of basement membrane glycoproteins. An immunohistochemical approach. 282 85

Human hepatoma cell lines were shown for the first time to contain various types of procollagen mRNAs. The amounts and types of procollagen mRNAs differed depending on the cell lines. Pro alpha 1 (III) and pro alpha 1 (IV) collagen mRNAs were present in PLC/PRF/5, a hepatocellular carcinoma cell line, whereas pro alpha 1 (I), pro alpha 2 (I), pro alpha 1 (IV) and pro alpha 2 (V) collagen genes contrast, HepG2 cells derived from hepatoblastoma contained little, if any, mRNAs for these types of procollagens we had examined.
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PMID:Presence of different types of procollagen messenger RNAs in human hepatoma cell lines. 282 74

Type V collagen-degrading enzyme activity in the cancer front was extremely high in a hepatocellular carcinoma (HCC) patient with severe metastasis to the lungs. However, the similar results were not found in other two patients with only slight or no metastasis.
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PMID:Elevation of type V collagen-degrading enzyme activity in invasive hepatocellular carcinoma. 282 27

The activity of serum type IV collagen-degrading enzyme was measured in 18 patients with hepatocellular carcinoma (HCC). The enzyme activity was significantly higher, in HCC patients with a tumor thrombus in the portal vein than in healthy controls, liver cirrhosis patients and HCC patients without a tumor thrombus. Moreover, the activity in HCC patients with lung metastasis tended to be higher than that in HCC patients without lung metastasis. The activity of serum type IV collagen-degrading enzyme did not correlate with tumor size, serum alpha-fetoprotein level, or macroscopic classification of tumor growth. These results suggest that the activity of serum type IV collagen-degrading enzyme represents the metastatic potential or the ongoing metastatic activity of HCC. The enzyme is a useful serum marker of metastasis from HCC.
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PMID:Serum type IV collagen-degrading enzyme in hepatocellular carcinoma with metastasis. 283 17


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