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)

We have immunohistochemically localized fibronectin, lysozyme and alpha-fetoprotein (AFP) in 21 human hepatocellular carcinoma (HCC) tissues obtained by surgical resection at both light and electron microscopic levels. Three distinct distribution patterns of fibronectin (sinusoidal, periacinar, and pericellular patterns) were observed. The sinusoidal and periacinar patterns were mainly observed in HCC of pseudoglandular or trabecular patterns and of Edmondson's grade I or II, whereas the pericellular pattern was observed in HCC of compact or trabecular patterns and of Edmondson's III grade, suggesting that the pericellular fibronectin was rather associated with undifferentiated HCC. Electron microscopic observation of the pericellular fibronectin showed fibronectin to be present in the dilated intercellular spaces where microvilli were moderately developed. We observed intracytoplasmic staining of fibronectin in 2 of the 21 HCC cases. By immunoelectron microscopy, fibronectin was observed in the endoplasmic reticulum (ER) of some HCC cells. In the 21 HCC cases, lysozyme-positive cancer cells were observed in 10 cases, and AFP in 6 cases. At the ultrastructural level, lysozyme was identified in the ER and the perinuclear spaces of HCC cells, suggesting that lysozyme was synthesized by these cells. Lysozyme-positive cases tended to be more frequently observed in cases with the pericellular pattern of fibronectin rather than those with sinusoidal or periacinar patterns.
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PMID:Immunohistochemical study of fibronectin, lysozyme, and alpha-fetoprotein (AFP) in human hepatocellular carcinoma. 243 68

Intra and extracellular localization of alpha-fetoprotein (AFP) has been studied by an indirect peroxidase labeled antibody method using 12 cases of human hepatocellular carcinoma (HCC). With light microscopic observation, positive immuno-staining for AFP was observed in 6 out of 12 cases and demonstrated as granular or diffuse deposits in the cytoplasm of neoplastic hepatocytes. In electron microscopic studies, 8 cases showed the positive immuno-staining for AFP in the neoplastic hepatocytes. Intracellular antigen was well circumscribed within certain cell organelles with the positive immuno-staining for AFP being observed in perinuclear space, cisternae of rough endoplasmic reticulum (RER), Golgi complexes, and secretory vesicles. In addition, the positive immuno-staining for AFP was observed in bile canaliculus-like space in most cases with increased levels serum AFP and in some cases which showed normal levels of serum AFP. Furthermore, the positive immuno-staining for AFP was also observed in intercellular, Disse's-like and sinusoid-like spaces, and micropinocytotic and lysosome-like vesicles in the endothelial cells in a few cases which showed excessively high value of serum AFP.
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PMID:An immuno-electron microscopic study on intra and extracellular localization of alpha-fetoprotein in human hepatocellular carcinoma. 244 59

Immunoreaction of alpha-fetoprotein (AFP) has been described in cholangiolar "oval" cells in the early stage of 3'-methyl-4-dimethylaminoazobenzene hepatocarcinogenesis. The subcellular location of AFP in the oval cells was in the perinuclear space, rough endoplasmic reticulum and Golgi apparatus. In livers with hyperplastic nodules there were two different types of foci containing AFP-positive cells. One type had a normal nucleocytoplasmic ratio and was seen in well-preserved hepatic trabecular structures, and the other had less cytoplasm and occurred in trabecular structures in disarray. AFP-immunoreactivity in the former type was visible in the perinuclear space and rough endoplasmic reticulum but scarce in the Golgi apparatus, and in the latter type it was present in the proliferative smooth endoplasmic reticulum and in several parts of Golgi apparatus in the submembranous or pericanalicular areas. In livers with hepatocarcinoma, AFP immunoreaction was detected in well-differentiated hepatocellular carcinomas, and the subcellular location of AFP was in the perinuclear space, rough endoplasmic reticulum and many developed Golgi complexes. Therefore, AFP-positive cells in livers with hyperplastic nodules are a new cell population in hepatocarcinogenesis, and each type is morphologically different from the oval cell.
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PMID:Demonstration by light and ultrastructural immunoperoxidase study of alpha-fetoprotein-positive non-hepatoma cells and hepatoma cells during 3'-methyl-4-dimethylaminoazobenzene hepatocarcinogenesis. 245 81

Alpha-fetoprotein (AFP) synthesis in non-malignant liver tissue of 34 patients with chronic hepatitis or liver cirrhosis, some of whom also had hepatocellular carcinoma (HCC), was studied by light and ultrastructural immunohistochemistry using peroxidase-labeled anti-human AFP. Simultaneously, the serum level of AFP was measured in these patients by radioimmunoassay. AFP-positive cells were identified in non-malignant liver tissue of 7 patients with elevation of serum AFP. AFP was demonstrated in several hepatocytes which were clustered in hepatic lobules, and also in some bile ductular cells which were distributed in the periphery of portal tracts. In an immunoelectron microscopic study of AFP-positive hepatocytes, dense reaction products of anti-AFP were localized in the membranes and cisternae of rough endoplasmic reticulum (r-ER), perinuclear space (PNS) and Golgi apparatus. The prominent feature of AFP-positive hepatocytes was abundant r-ER encompassing many mitochondria. As to AFP-positive bile ductular cells, they had scanty cytoplasm and few intracytoplasmic organelles and were surrounded by basement membrane. AFP was focally localized in the r-ER of such bile ductular cells. These observations suggest that AFP can be produced by malignant and non-malignant liver cells and that in non-malignant liver tissues, AFP can be produced by two distinct cell types; bile ductular cells and hepatocytes themselves.
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PMID:Immunoelectron microscopic observation of alpha-fetoprotein synthesis in human non-malignant liver tissues using immunoperoxidase methods. 246 Mar 91

Smooth and rough endoplasmic reticulum of two Morris hepatomas, the slow growing 9618A and the fast growing 3924A, have been isolated, and their biochemical composition, supramolecular organization, and response to the action of peroxidative agents have been studied. Cytochrome P450 content and lipid availability are the limiting factors of their peroxidizability. The hemoprotein content is reduced about 80% in hepatoma 9618A and is virtually absent in hepatoma 3924A. The peroxidizability decreases with increasing growth rate of the tumor. The protein, phospholipid, and cholesterol content, the fatty acid composition as well as the double bond index, and the saturated and unsaturated fatty acid content are reported. Differences have been found between normal liver and tumors and between the fractions within a given tumoral tissue. The molecular order, as determined by fluorescence anisotrophy decay of DPH, increases in total microsomes and in the smooth fraction going from liver 9618A to 3924A, whereas for the rough fraction it is the same in liver and hepatoma 9618A; in 3924A it increases of about 30%. Fluidity decreases in total microsomes going from liver to 3924A, to 9618A. In both the purified fractions it decreases with increasing deviation of the tumor.
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PMID:Lipid peroxidation and physical properties of smooth and rough hepatoma microsomes. 246 86

Previous studies in this laboratory (1) have shown that tunicamycin-treatment inhibits the secretion of three secretory glycoproteins--alpha 2-macroglobulin, ceruloplasmin, and alpha 1-protease inhibitor in human hepatoma (Hep G2) cell cultures. In the present study, we have investigated (i) their site of accumulation within the endoplasmic reticulum/Golgi pathway, and (ii) the solubility characteristics of these unglycosylated proteins. Using percoll density gradient centrifugation, we found that tunicamycin-treatment markedly inhibited the transport of alpha 2-macroglobulin, ceruloplasmin and alpha 1-protease inhibitor from the rough endoplasmic reticulum. However, there was no detectable changes in their solubility properties as both the glycosylated and unglycosylated species were associated with the 100,000 xg supernatant fraction following disruption of the microsomal fraction (i) with 0.2% Triton X-100 and (ii) by repeated freeze-thaw cycles. Also no evidence of protein aggregation was detected by liquid chromatography of the unglycosylated proteins on Bio-Gel A-1.5 column.
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PMID:Accumulation of unglycosylated liver secretory glycoproteins in the rough endoplasmic reticulum. 247 24

Immunoreaction of alpha-fetoprotein (AFP) was detected not only in well-differentiated hepatocellular carcinoma but also in hepatocytes forming foci in livers with hyperplastic nodules during 3'-methyl-4-dimethylaminoazobenzene hepatocarcinogenesis. The subcellular location of AFP in hepatoma cells was in the rough endoplasmic reticulum, perinuclear space and well-developed Golgi apparatus around the nucleus. In livers with hyperplastic nodules it was also in some parts of the smooth endoplasmic reticulum and Golgi regions in hepatocytes in the vicinity of submembranous areas or bile canaliculi. These findings suggest that the Golgi apparatus in hepatoma cells acts mainly as an organelle for glycosylation of AFP and that the Golgi complexes in the hepatocytes in livers with hyperplastic nodules are organelles for secretion of AFP. Combined light microscopic immunoperoxidase study and autoradiography with 3H-thymidine revealed a higher cumulative labeling index in AFP-positive hepatoma cells than in non-tumorous areas. Combined electron microscopic immunoperoxidase study and autoradiography showed that hepatoma cells with AFP immunoreactivity only in the rough endoplasmic reticulum had a significantly higher labeling index than did cells with AFP immunoreactivity in both rough endoplasmic reticulum and Golgi apparatus. These findings suggest that AFP is synthesized in hepatoma cells before or during the stage of their DNA synthesis and is then transported to the Golgi apparatus.
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PMID:Mechanisms of alpha-fetoprotein synthesis in hepatoma cells. Combined electron microscopic immunocytochemistry and autoradiography. 247 70

In the present investigation we compared the glycoprotein DPP IV from rat liver and Morris hepatoma 7777 by means of biochemical and immunological methods. For that purpose nine monoclonal anti-DPP IV-antibodies recognizing four different epitopes and a monospecific anti-DPP IV-antiserum were applied. In the homogenates of both tissues a plasma membrane-bound and a soluble form were detected. The immunological cross-reactivity of both forms was demonstrated with the antiserum and the monoclonal antibodies against the epitopes A, B and C while epitope D was restricted to liver plasma membrane. Differences of the distinct DPP IV forms were exhibited in the molecular weights, isoelectric points and peptide maps. In the hepatoma homogenate only 10% of DPP IV activity was found compared to normal liver but the ratio of soluble to membrane-bound form is higher in the hepatoma than in the liver. The fractionation of the homogenates into different cell components revealed for the liver a continuous increase of DPP IV activity from the endoplasmic reticulum fractions to the Golgi apparatus and finally to the plasma membranes. By contrast, in hepatoma the flow from the Golgi apparatus to plasma membrane was greatly reduced. The loss of DPP IV from the surface of cultured hepatoma cells was concomitant with a decrease of cell-substratum adhesion. DPP IV was found to be inserted into the liver plasma membrane by two different mechanisms, a phospholipase C-sensitive and a papain-sensitive one. In the hepatoma the phospholipase C-sensitive anchorage was not expressed. Besides liver and hepatoma the distribution of DPP IV was characterized in various rat organs by enzyme activity, histochemistry and immunohistochemistry with the anti-DPP IV-antibodies.
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PMID:Biochemical properties of dipeptidyl peptidase IV in liver and hepatoma plasma membranes. 248 27

Using an indirect immunoperoxidase technique on frozen sections with the monoclonal antibody 96.5, we investigated the in situ distribution of melanotransferrin, a transferrin (Tf) and transferrin receptor (TfR) related glycoprotein, in human liver. Specimens included normal liver, liver in iron overload, hepatocellular carcinoma, angioma and foetal liver. On light microscopy, immunoreactivity was almost exclusively present on sinusoidal lining cells, apparently endothelial cells; the pattern was similar in normal and in iron-loaded liver. A gradient of more enhanced staining in acinar zone II and III was observed. The endothelial localization of the staining was supported by the positivity of the central vein endothelium and of the angiomas. Immunoelectron microscopy on three liver specimens showed positivity on sinusoidal endothelial cells but not on Ito and Kupffer cells. In addition, positivity on rough endoplasmic reticulum vesicles of some hepatocytes was also present. Four hepatocellular carcinomas showed an intense staining in tumour cells, 3 were weakly positive and 3 were negative. In the foetal livers, the central vein endothelium was positive from 21 weeks of gestation onward and additional positivity of zone III sinusoidal endothelial cells was present from 27 weeks on. The present results show that in the liver melanotransferrin has a localization different from Tf and the TfR. These latter molecules are predominantly localized in parenchymal cells. In addition, there does not appear to be a coordinate regulation secondary to iron storage, between melanotransferrin, Tf and the TfR. The observed gradient in the staining pattern in foetal and adult liver specimens further supports the heterogeneity of the endothelial cell population in the liver and suggests a developmental relationship between endothelial cells of sinusoids and central vein.
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PMID:In situ localization of melanotransferrin (melanoma-associated antigen P97) in human liver. A light- and electronmicroscopic immunohistochemical study. 254 Mar 89

Cytochemical electron microscopy of cultured rat hepatoma cells (AH-130) demonstrated that thiamine pyrophosphatase (TPPase) activity was localized in the Golgi complex. When the cells were treated with brefeldin A (BFA, 2.5 micrograms/ml) for 10 min, the characteristic structure of the Golgi stack was no longer observed, and TPPase was cytochemically stained in the vesicular and tubular structures scattered in the cytoplasm. A longer exposure of the cells to the drug (20 min to 1 h) resulted in the distribution of the TPPase activity in the endoplasmic reticulum (ER) and nuclear envelope. Such an unusual distribution of the enzyme activity, however, was reversible even in the presence of BFA. At 2 h after the exposure, the TPPase activity disappeared from the ER and was concentrated again in the vesicular and tubular structures. The enzyme activity was finally localized in the Golgi complex which was reassembled by 4 h after the exposure. The reversible effect of BFA may be due to a possible metabolism of the drug into an inert form during the incubation. Taken together, these results indicate that BFA causes a rapid disassembly of the Golgi complex and redistribution of the marker enzyme TPPase into the ER including the nuclear envelope. The spontaneous reversibility of the drug effect also favors a dynamic recycling of the Golgi marker between the ER and the Golgi complex under the conditions used.
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PMID:Dynamic distribution of the Golgi marker thiamine pyrophosphatase is modulated by brefeldin A in rat hepatoma cells. 255 14


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