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Query: UMLS:C0019204 (
hepatocellular carcinoma
)
71,386
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
An alpha-fucosyltransferase activity has been demonstrated in rat ascites
hepatoma
AH 7974F cells catalyzing the transfer of L-fucose to asialo-GM1 prepared from bovine brain GM1 ganglioside to form a fucolipid in the presence of Triton X-100. The radioactive fucolipid was shown to be Fuc-(alpha1 leads to 2)-
Gal
-(beta1 leads to 3)-GalNAc-(beta1 leads to 4)-
Gal
-(beta1 leads to 4)-Glc-ceramide from the following results. The radioactive product coincided with authentic blood group H-active fucolipid from AH 7974F cell on thin-layer chromatography. The product formed a precipitation line not only with Ulex europeus lectin but also with eel anti-H serum on agarose gel plates. The terminal 14C-labeled fucose was released by Bacillus fulminans alpha(1 leads to 2)fucosidase as well as Charonia lampas alpha-fucosidase. The optimum pH value for the incorporation of L-fucose into asialo-GM1 was 5.8 in cacodylate/HCl buffer. The fucosyltransferase was highly specific for asialo-GM1.
...
PMID:Enzymic synthesis of a new type of fucose-containing glycolipid with fucosyltransferase of rat ascites hepatoma cell, AH 7974F. 3 11
The highly malignant rat
hepatoma
27 was found to have increased amounts of lipid-bound sialic acid as compared with normal liver whereas in regenerating liver the lipid-bound sialic acid level was reduced. In contrast to the liver the
hepatoma
contained higher amounts of disialogangliosides and no trisialogangliosides, which are abundant in the liver. The main disialoganglioside of the
hepatoma
had no analogue among the liver gangliosides and was identified as
Gal
-GalNAc(AcNeu-AcNeu)-Glc-Cer (GD1b), which in other tissues is known to be a precursor of trisialogangliosides. These findings may be explained by a reduced activity of glycosyltransferases in the
hepatoma
and apparently do not simply reflect differences in growth rate since the ganglioside pattern of regenerating rat liver was not altered significantly in comparison with the liver. Liver and
hepatoma
microsomes were found to be enriched in gangliosides as compared with whole cells, liver mitochondria were slightly poorer, while the ganglioside level of
hepatoma
mitochondria was much higher than that of the
hepatoma
cells. It thus appears that the existing image of the plasma membranes as the only sites of high ganglioside concentration may not hold true for weakly differentiated hepatomas of high malignancy.
...
PMID:Gangliosides of hepatoma 27, normal and regenerating rat liver. 17 87
The relationship between cell differentiation/tumorisation and plasma membrane glycoproteins was approached using peanut agglutinin (PNA) a lectin specific for the
Gal
-beta(1,3)GalNAc sequence and a homologous cell system consisted of normal rat hepatocytes (HyC) and a poorly differentiated
hepatoma
(ZHC). This work is focused on the molecular nature of PNA receptors. PNA bound strongly to ZHC, but bound very weakly, if at all to hepatocytes. After sialidase treatment this binding was slightly enhanced in ZHC and HyC. The total number of binding sites on ZHC was 9.6 x 10(6)/cell and 1.2 x 10(7)/cell before and after sialidase treatment respectively. In contrast, this number could not be calculated on HyC, even after sialidase treatment. The PNA receptors were isolated and identified from ZHC using affinity chromatography on immobilized PNA and lectin overlay. Two bands were revealed after SDS-PAGE of PNA receptors: a major one with a relative molecular mass of 160 kDa and a minor one of 110 kDa. The latter disappeared after sialidase treatment of ZHC suggesting the possibility that these two bands could be less and more sialylated forms of the PNA receptors, respectively. In contrast no PNA receptors could be detected on HyC. These PNA receptors could be considered O-linked glycoproteins containing the
Gal
-beta(1,3)GalNAc disaccharide because: i) PNA carbohydrate specificity toward this disaccharide found in this glycoprotein type; ii) their carbohydrate composition with
Gal
and GalNAc but not man residues; iii) their sensitivity to alkaline treatment; and iv) strong inhibition of PNA binding to ZHC with the
Gal
-beta(1,3)GalNAc structure. The absence of PNA receptors on HyC appeared to be related to the absence of this glycoprotein containing the disaccharide but not to the change or failure of glycosylation of the polypeptide chain of PNA receptors. The relationship between the presence of PNA receptors and differentiation/tumorisation phenomena as well as the mechanism that induced the expression of these receptors are discussed.
...
PMID:Identification of peanut agglutinin receptors related to the state of tumoral liver cell differentiation. 157 2
Two murine monoclonal antibodies, 2A3D2 and 2D11E2 (both IgM), which are directed to the gangliosides and sialoglycoproteins related to a rare blood group antigen, Cad, were obtained by using a ganglioside mixture prepared from human
hepatocellular carcinoma
cells (PLC/PRF/5) as the immunogen. These two monoclonal antibodies detected multiple ganglioside antigens present in the PLC/PRF/5 cells, and the major antigenic ganglioside was characterized as IV4GalNAc beta-GD1a, which has the carbohydrate structure GalNAc beta 1----4(NeuAc alpha 2----3)
Gal
beta 1----3GalNAc beta 1---- 4(NeuAc alpha 2----3)
Gal
beta 1----Cer. The two antibodies also reacted with GM2 (GalNAc beta 1----4[NeuAc alpha 2----3]
Gal
beta 1----4Glc beta 1----Cer) and a Cad-active lactoseries ganglioside (IV4GalNAc beta-sialosylparagloboside, GalNAc beta 1----4[NeuAc alpha 2----3]
Gal
beta 1----4GlcNAc beta 1---- 3Gal beta 1----4Glc beta 1----Cer), which have carbohydrate structures related to IV4GalNAc beta-GD1a. Beside gangliosides, both antibodies recognized the carbohydrate determinant carried by glycophorin A on very rare Cad-positive human RBC; the structure of which is GalNAc beta 1----4(NeuAc alpha 2----3)
Gal
beta 1----3(NeuAc alpha 2---- 6)GalNAc alpha 1----Ser/Thr. From these findings, it is clear that monoclonal antibodies 2A3D2 and 2D11E2 both recognize the nonreduced carbohydrate terminus composed of three sugar residues, GalNac beta 1----4(NeuAc alpha 2----3)
Gal
beta 1----R, and are useful for detecting the Cad-related antigen in cells and tissues. By using these monoclonal antibodies, it was revealed that many cultured human
hepatocellular carcinoma
cell lines and cancer tissues taken from patients with
hepatocellular carcinoma
contain both Cad-active glycoprotein antigens and related gangliosides, while normal liver tissues contain no appreciable amount of either species of antigen. The Cad-active glycoprotein antigens in cultured human
hepatocellular carcinoma
cells appeared as triplet bands having molecular weights of 92,000, 75,000, and 61,000, under either reducing or nonreducing conditions in sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Essentially the same triplet proteins were observed in as many as 4 of 9 cases (44%) of cancer tissue from patients with
hepatocellular carcinoma
, but not in neighboring cirrhotic tissues or normal livers tissues. These results suggest that the rare blood group antigen Cad is associated with human cancers, especially
hepatocellular carcinoma
.
...
PMID:Gangliosides and sialoglycoproteins carrying a rare blood group antigen determinant, Cad, associated with human cancers as detected by specific monoclonal antibodies. 216 57
1.
Gal
beta 1-4GlcNAc alpha 2-6 sialyltransferase was assayed in FAZA
hepatoma
cells and the cell culture medium following growth of cells in presence of dexamethasone and phorbol ester. 2. There was about a seven-fold increase in sialyltransferase activities in cells and medium in presence of dexamethasone with the maximum effect occurring at 10(-6)-10(-7) M dexamethasone. 3. The presence of 10(-6) M phorbol ester in the culture medium increased sialyltransferase activities in cells and medium by ca 40% over the values found with dexamethasone alone. 4. The use of the FAZA
hepatoma
cell line for studies on sialyltransferase is compared with the primary hepatocyte system reported on earlier (Woloski et al., 1986).
...
PMID:Stimulation of release of Gal beta 1-4GlcNAc alpha 2-6 sialyltransferase from the FAZA hepatoma cell line by dexamethasone and phorbol ester. 218 55
Previously, monoclonal antibody FDC-6 was established, which defines a structure specific for fibronectins isolated from fetal and malignant cells and tissues. The presence of the FDC-6-defined structure at type III connecting segment (III CS) is characteristic of oncofetal fibronectin (onf-FN), and its absence is characteristic of normal fibronectin (nor-FN) (Matsuura, H., and Hakomori, S. (1985) Proc. Natl. Acad. Sci. U. S. A. 82, 6517-6521).
Hepatoma
fibronectin was sequentially digested by various proteases, followed by subsequent chromatography on an FDC-6 affinity column and reverse-phase columns at each step of digestion. A single strongly active glycosylhexapeptide (glycopeptide 1) and an inactive glycosylpentapeptide (glycopeptide 3) were isolated from glycopeptide A containing 35 amino acid residues. The minimum essential structure required for the FDC-6 activity was found to be a hexapeptide sequence Val-Thr-His-Pro-Gly-Tyr having NeuAc alpha 2----3Gal beta 1----3GalNAc or its core (
Gal
beta 1----3GalNAc or GalNAc) linked at threonine. Various synthetic peptides including the Val-Thr-His-Pro-Gly-Tyr sequence and a glycopeptide having the Val-Thr-His-Pro-Gly pentapeptide with the same glycosylation at threonine were all inactive. Elimination of sialic acid slightly increased the activity, and subsequent elimination of galactose did not alter the activity; however, removal of the
Gal
beta 1----3GalNAc residue by endo-alpha-N-acetylgalactosaminidase from desialylated glycopeptide A resulted in total inactivation of the reactivity with FDC-6 antibody. Thus, a single glycosylation at a defined threonine residue of the III CS region may induce conformational changes in the peptide to form the specific oncofetal epitope recognized by FDC-6 antibody. This finding opens the possibility that a number of other oncofetal epitopes consist of a peptide and a common O-linked carbohydrate and that the combination produces a conformation specific to cancer or to a stage of development.
...
PMID:The oncofetal structure of human fibronectin defined by monoclonal antibody FDC-6. Unique structural requirement for the antigenic specificity provided by a glycosylhexapeptide. 244 38
The sugar chains of transferrin samples, purified from sera of patients with
hepatocellular carcinoma
and of healthy individuals, were released quantitatively as radioactive oligosaccharides by hydrazinolysis followed by N-acetylation and NaB3H4 reduction. Comparative study of their structure by serial lectin column chromatography, by Bio-Gel P-4 column chromatography, and by sequential exoglycosidase digestion revealed that prominently altered glycosylation is commonly found in the
hepatoma
transferrins, although they all contain two complex-type asparagine-linked sugar chains in one molecule like in the case of normal transferrins. The alteration is quite various, including the increase of highly branched sugar chains, of those with the
Gal
beta 1----4(Fuc alpha 1----3)GlcNAc beta 1----and the Neu5Ac alpha 2----3Gal beta 1----4GlcNAc beta 1----groups in their outer chain moieties and of those with a fucosylated trimannosyl core. Many but not all of the
hepatoma
transferrin samples contained a small amount of a bisected biantennary sugar chain, which was not detected in the normal transferrin samples.
...
PMID:Altered glycosylation of serum transferrin of patients with hepatocellular carcinoma. 253 9
Sera from the patients with chronic liver diseases and
hepatocellular carcinoma
(
HCC
) were tested for reactivity with neutral glycosphingolipids extracted from rabbit liver plasma membrane by enzyme-linked immunosorbent assay and thin-layer chromatography immunostaining. IgG class antibody to neutral glycosphingolipids was detected in 29.6% (8 of 27), 6.3% (1 of 16), 0% (0 of 8), 0% (0 of 25), and 6.9% (2 of 29) in the sera of patients with
HCC
, liver cirrhosis, autoimmune chronic active hepatitis, chronic hepatitis, and normal individuals, respectively. Using the serum positive for the antibody to neutral glycosphingolipids, the target antigen glycolipid was isolated. Negative ion fast atom bombardment mass spectrometry, exoglycosidases treatment, and permethylation analysis revealed that the main target antigen was IV3 alpha
Gal
-nLc4Cer. In enzyme-linked immunosorbent assay, IgG class antibody to IV3 alpha
Gal
-nLc4Cer was detected in 33.3% (9 of 27), 18.8% (3 of 16), 25% (2 of 8), 4% (1 of 25), and 6% (3 of 50) in the sera of patients with
HCC
, liver cirrhosis, autoimmune chronic active hepatitis, chronic hepatitis, and normal individuals, respectively. Of 9
HCC
patients positive for the antibody, 6 had received transcatheter arterial embolization (TAE) therapy. Six of 10 patients who received TAE therapy had the antibody, whereas only 3 of 17 patients without TAE therapy had the antibody. This antibody may be a heterophile antibody, which recognizes
Gal
alpha 1-3Gal structure at the nonreducing terminal of the antigen. Since the occurrence of this antibody was closely related with TAE therapy, the necrosis of
HCC
induced by TAE therapy may stimulate the production of the antibody.
...
PMID:Significant increase in the antibody to Gal alpha 1-3Gal structure in sera of patients with hepatocellular carcinoma after transcatheter arterial embolization. 254 42
Previously established human monoclonal antibodies (MAbs) directed to carbohydrate antigens are essentially all IgM class, and show relatively low affinity and low reactivity at 37 degrees C. We report here the establishment of a human IgG3 MAb displaying high affinity antigen-binding activity at 37 degrees C and efficiently activating cellular cytotoxicity directed to human tumor cell lines expressing the polylactosamine antigen. The IgG3 MAb (MH21-134) reacted with the repeated unbranched polylactosamine structure
Gal
beta 1----4GlcNAc beta 1----3Gal beta 1----4GlcNAc beta 1----3Gal beta 1----R, i.e., nLc6, nLc8, etc., but did not react with sialyl 2----3 or 2----6 substituted derivatives at the terminal
Gal
. This specificity differs from that of several anti-i antibodies, or human anti-i-like MAbs which react with sialyl 2----3 substituted structures. Directly biotinylated MH21-134 antibody was used in immunohistochemical staining of 154 formalin-fixed, paraffin-embedded tissue sections to study distribution of the antigen. High incidence of positive staining was found in colon cancer (11/17; 65%) and
hepatocellular carcinoma
(8/12; 67%), followed by large cell and squamous cell carcinoma of lung cancer (10/13; 59%, and 14/26; 54%, respectively). TLC immunostaining of glycolipid extracts from a variety of tumor tissues showed the presence of nLc6 and/or nLc8 in over 50% of cases. The antigens nLc6 and nLc8 were found to be absent from normal colonic epithelia, kidney, and pancreas. Only a weak band corresponding to nLc8 and one corresponding to nLc6 were found in liver and spleen, although all these normal tissues, including gastrointestinal epithelia, lung, liver, spleen, erythrocytes, and lymphocytes, were essentially negative on immunohistology. However, the antigen was found to be highly expressed in myelocytes and weakly in bronchial glands of lung and pancreatic duct epithelia. Nevertheless, expression of unsubstituted, unbranched polylactosamine antigen could be an important basis for induction of humoral immune response against certain types of human cancer, despite its limited expression in normal cells.
...
PMID:Human IgG3 monoclonal antibody directed to an unbranched repeating type 2 chain (Gal beta 1----4GlcNAc beta 1----3Gal beta 1----4GlcNAc beta 1----3Gal beta 1----R) which is highly expressed in colonic and hepatocellular carcinoma. 255 93
Mammalian hepatic asialoglycoprotein receptors (ASGP-R) are composed of two unique, but closely related polypeptides, which in the rat are designated rat hepatic lectins 1 and 2/3 (RHL 1, RHL 2/3). Despite numerous studies, the composition of a functional ASGP-R has remained unclear. We examined this question in rat
hepatoma
tissue culture (HTC) cells (which lack endogenous ASGP-R) that were co-transfected with cDNAs for both RHL 1 and RHL 2/3. The original population was cloned, but derivatives were unstable. We therefore used fluorescence-activated cell sorting to separate a subpopulation of cells (positive) that specifically endocytosed fluoresceinated asialoorosomucoid (ASOR) from one that did not (negative). We then used indirect immunofluorescence with polypeptide-specific ASGP-R antibodies, immunoanalysis, and binding and uptake studies with two
Gal
ligands (ASOR and NAc-galactosylated poly-L-lysine (
Gal
-Lys] to further define the ASGP-R status in these two populations. As reported by others, we found that expression of both RHL 1 and RHL 2/3 in the positive cells resulted in binding, uptake and degradation of ASOR, the most commonly used ASGP-R ligand. The negative cells expressed only RHL 1 and neither bound nor processed ASOR. However, the presence of RHL 1 was sufficient for specific high affinity binding and processing of the synthetic ligand,
Gal
-Lys, by negative cells. These results show that RHL 1 can function as an ASGP-R, given a highly galactosylated ligand, and that RHL 2/3 must play an important role in the organization of native ASGP-R in the membrane.
...
PMID:The major subunit of the rat asialoglycoprotein receptor can function alone as a receptor. 264 1
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