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)

Detailed time courses of uptake of labeled 3-O-methyl-D-glucose and 2-deoxy-D-glycose by untreated and ATP-depleted Novikoff rat hepatoma cells were determined as function of concentration (0.2-10 mM) by a rapid mixing/sampling technique which allows uptake measurements in time intervals as short as 1.5 seconds. Intracellular accumulation of 3-O-methylglucose in untreated and ATP-depleted cells and of deoxyglucose in ATP-depleted cells to equilibrium followed pseudo-first order kinetics and initial velocities were computed from overall time courses of substrate accumulation. Initial velocity was a Michaelis-Menten function of exogenous substrate concentration. The estimated kinetic constants for zero-trans transport of 3-O-methylglucose were about the same for untreated and ATP-depleted cells (Kztm = 1.73 +/- 0.24 mM; Vztmax = 28.8 +/- 3.6 pmoles/microliter cell H2O. sec) and were similar to those for deoxyglucose transport in ATP-depleted cells (Kztm = 0.65 +/- 0.1 mM; Vztmax = 19.6 +/- 1.6 pmoles/microliter cell H2O. sec). Similar kinetic parameters were obtained for the transport of D-glucose and D-galactose in ATP-depleted cells. The transport of 3-O-methylglucose and deoxyglucose were inhibited by each other in a simple competitive manner with apparent Ki's similar to their transport Km's. In untreated cells, in which deoxyglucose was phosphorylated, intracellular steady-state levels of free deoxyglucose accumulated within 10 to 20 seconds of incubation regardless of its concentration in the medium. Thereafter, the rate of deoxyglucose incorporation into total cell material reflected the rate of phosphorylation rather than the transport rate. The rate of deoxyglucose transport exceeded the initial rate of its phosphorylation by 20-40 %. The intracellular steady-state-levels observed during the first 2 minutes of incubation decreased from about 40% of equilibrium level at 0.2 mM deoxyglucose to about 8% at 10 mM. Computer fits of a kinetic equation describing transport and phosphorylation as independent processes operating in tandem to these data are consistent with the observed kinetic constants for hexose transport and hexokinase activity with deoxyglucose as substrate. Upon longer incubation (2-10 minutes) the rate of deoxyglucose uptake by the phosphorylating cells decreased progressively, concomitant with a decrease in intracellular ATP and an increase in intracellular deoxyglucose to equilibrium levels. It is demonstrated that the rate of deoxyglucose uptake, measured at two or more minutes, seriously underestimates the hexose transport rate and yields misleading conclusions regarding the extent and type of inhibition by transport inhibitors, such as persantin or cytochalasin B. Persantin inhibited hexose transport in a simple non-competitive manner (Ki = 20 muM) indicating that the drug affects the function of the hexose carrier.
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PMID:Deoxyglucose and 3-O-methylglucose transport in untreated and ATP-depleted Novikoff rat hepatoma cells. Analysis by a rapid kinetic technique, relationship to phosphorylation and effects of inhibitors. 67 Mar 3

For the first time, change in the proton longitudinal relaxation times (T1) of rat tissues has been examined throughout the whole process of azo-dye hepatocarcinogenesis. Two maxima of the T1 values were observed for liver, on Day 60 and after Day 120, and these changes correlated well with the changes in water content. The first peak was ascribed to the immature hepatocytes of hyperplastic nodules, and the second peak to the developed hepatoma cells. The significance of the change in T1 values as a preneoplastic change is discussed.
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PMID:Biphasic change of proton magnetic relaxation times during azo-dye hepatocarcinogenesis. 69 37

The carcinogenic activity of orally administered N-bis(2-hydroxypropyl)-nitrosamine (DHPN) in male Wistar rats was evaluated with respect to its dose. DHPN was administered at two doses, 100 ppm and 500 ppm, in the drinking water to rats for 25 to 52 weeks. Tumors developed in the lung, liver, and thyroid of rats receiving 100 ppm DHPN and in the lung, liver thyroid, esophagus, kidney, and urinary bladder of rats receiving 500 ppm DHPN. The principal target organ was the lung in rats receiving either 100 or 500 ppm DHPN, indicating that the carcinogenic action of these doses of DHPN was similar to that of higher doses previously reported. Histologically, the tumors were adenoma, adenocarcinoma, squamous cell carcinoma, and combined carcinoma of the lung, hepatocellular carcinoma and hemangioma of the liver, adenoma and adenocarcinoma of the thyroid, squamous cell papilloma and carcinoma of the esophagus, renal cell and transitional carcinoma of the kidney, and transitional cell carcinoma of the urinary bladder. No pancreatic tumors were observed.
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PMID:Effect of dose on the carcinogenic activity of orally administered N-bis(2-hydroxypropyl)nitrosamine in rats. 71 Aug 6

Transverse cross-sectional images which represent the spatial distribution of the proton nuclear magnetic resonance signal in a live Wistar rat have been produced by the multiple-sensitive-point method. The images form a chronological series demonstrating the detection and development of a D23 hepatoma in the abdomen. Discrimination of the tumor is by contrast with the surrounding tissue and is attributed to the elevated water content and relaxation times of the former.
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PMID:In vivo tumor discrimination in a rat by proton nuclear magnetic resonance imaging. 76 Dec 19

Livers of 6- to 7-week-old male C3H/He, CBA, A, and BALB/c mice were examined by electron microscopy for the presence of intracisternal A particles (ICAP) after administration of diethylnitrosamine (DEN) in drinking water. In control mice, ICAP were extremely rare; they were found in the livers of only 2 mice (strains C3H/He and A; none in the other strains). By contrast, the treatment of mice with DEN greatly enhanced the appearance of ICAP in the liver cells of all strains. Within 2 weeks of the treatment, ICAP were found in 8-26% of liver cells examined in all mice and the number of ICAP/cell ranged from 3 to 12. Aside from mild disorganization of the rough endoplasmic reticulum, such as segmentation and vesiculation, liver cells of carcinogen-treated mice showed none of the consistent abnormalities that characterize the appearance of ICAP. The reactivation of ICAP (which are usually suppressed in adult mice) by DEN may become a useful marker for analysis of the sequential alterations of the liver that lead to the development of hepatoma during carcinogenesis.
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PMID:Activation of intracisternal A particles in mouse liver by diethylnitrosamine. 84 86

Trichloroethylene (TCE), a structural analog of vinyl chloride, is known to induce hepatocellular carcinoma and other tumors in C57BL/6 X C3H/He F1 (hereafter known as B6C3F1) hybrid mice. TCE epoxide, a possible metabolite, is expected to be highly reactive toward cellular nucleophiles, e.g., proteins and nucleic acids. Hence, the microsomal metabolism of TCE and its covalent binding to microsomal protein were examined. Rat liver microsomes were incubated in vitro with [14C]TCE. The results showed that TCE binds covalently to microsomal protein since extensive organic extractions and Pronase digestion do not dissociate the TCE-protein complex. The binding was decreased by 7,8-benzoflavone, blocked by SKF-525A, and enhanced by i.p. administration of phenobarbital. The possibility that TCE epoxide, once formed, could be converted to water-soluble products through enzymatic hydrolysis by epoxide hydrase was also investigated. Addition of 3,3,3-trichloropropene oxide, a potent inhibitor of epoxide hydrase, to the incubation system markedly enhanced the binding of TCE. These observations support the view that, in order to bind to protein, it is necessary for TCE to be metabolized to its epoxide, a reactive intermediate that is most likely involved in TCE carcinogenesis and toxicity.
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PMID:Covalent interaction of metabolites of the carcinogen trichloroethylene in rat hepatic microsomes. 127 48

Of 210 patients with hepatocellular carcinoma (n = 135), metastatic liver cancer (n = 71) and cholangiocarcinoma (n = 4) who underwent intra-arterial infusion of adriamycin and/or mitomycin C oil suspension (ADMOS) and cisplatin, and both regimens, pyogenic liver abscess occurred in seven (3.3%). The percentages of abscess formation in the respective types of liver cancer were 0.8, 7.0 and 25%. These differences among the three types of liver cancer were attributed to the volume of the tumor vascular beds to be embolized, which might determine the relative amount or regional Lipiodol retention in the tumor and normal liver tissue. Four of seven patients with hepatic abscess had received the intra-arterial infusion of ADMOS, and their angiographic findings showed sequential decreases in the vascular beds of the tumor in comparison with those of previous infusion procedures; all had hypovascular liver tumors angiographically. We have never experienced this complication in other treatments such as embolization of the hepatic arteries and intra-arterial infusion of water-soluble anticancer drugs alone. These results suggest that the most important factor leading to abscess formation is the ischemic destruction of the intrahepatic ducts secondary to occlusion of the peribiliary arterial plexus by Lipiodol and/or the direct effects of anticancer drugs on these vessels. To avoid this complication, the volume of Lipiodol used for intraarterial infusion therapy should be carefully determined, especially when the patient has hypovascular tumors of the liver and a history of multiple previous intraarterial infusion procedures of anticancer drug. The use of ADMOS should be avoided in patients with hypovascular tumors of the liver such as secondary deposits and cholangiocarcinoma.
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PMID:[Liver abscess formation after treatment of liver cancer by arterial injection using adriamycin/mitomycin C oil suspension (ADMOS)]. 131 61

To ascertain anorexigenic effect of toxohormone-L, a polypeptide extracted and purified from ascites of patients with hepatoma were infused into the rat third cerebroventricle. Food intake decreased on the first day after infusion of an optimum dose of 10.0 micrograms (p less than 0.05). The suppressive effect on feeding was linearly dose dependent (p less than 0.05). Meal size and latency to the first meal decreased in the 12-h dark period, and the first and the second 4-h cumulative blocks after infusion of a 10.0 micrograms dose (p less than 0.01 for each). The suppressive effects on total food intake and meal size were completely recovered within 24 h after infusion. Neither postprandial intermeal interval nor eating speed was affected. Periprandial drinking, a ratio of water intake to food intake, was not affected after infusion of 5.0 and 10.0 micrograms toxohormone-L. Infusion of a 10.0 micrograms dose showed no effect on ambulation. These findings suggest that anorexia and cachexia produced in cancer patients may essentially be due to the suppressive effect of toxohormone-L on food intake.
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PMID:Anorexia induced by toxohormone-L isolated from ascites fluid of patients with hepatoma. 132 17

The identification of free glycoinositol phospholipids (GPIs) following biosynthetic labeling with [3H]glucosamine in cultured cells has been reported by several laboratories. We applied this procedure to two of the cell types used in these studies, H4IIE hepatoma cells and isolated hepatocytes, but were unable to detect a [3H]glucosamine-containing lipid that met any of the criteria for GPIs, including sensitivity to phosphatidylinositol-specific phospholipase C (PIPLC) or GPI-specific phospholipase D. Part of the difficulty in radiolabeling a GPI by this procedure was the rapid metabolic conversion of [3H]glucosamine to galactosamine and neutral or anionic derivatives. A PIPLC-sensitive radiolabeled lipid was detected only after 16 h of labeling. The water-soluble fragments released from this lipid by PIPLC corresponded largely to myo-inositol 1,2-cyclic phosphate and myo-inositol 1-phosphate, products expected from PIPLC cleavage of phosphatidylinositol or lyso-phosphatidylinositol. In an alternative approach that we introduce here, free GPIs in lipid extracts from rat liver plasma membranes were labeled by reductive radiomethylation. This procedure, which radiomethylates primary and secondary amines, has been shown to label a glucosamine residue adjacent to inositol in all GPIs characterized to date. The labeled extracts were fractionated by two-dimensional thin-layer chromatography, and a cluster of polar labeled lipids were assigned as GPIs based upon the following observations. 1) They were cleaved by PIPLC, 2) after hydrolysis in 6 N HCl, both radiomethylated glucosamine and a glucosamine-inositol conjugate were identified by cation exchange chromatography, and 3) hydrolysis in 4 M trifluoroacetic acid generated a fragment consistent with glucosamine-inositol-phosphate. These results illustrate new criteria for the identification of GPIs. The labeled GPIs also contained radiomethylated ethanolamine, another component found in GPI anchors of proteins and in mature lipid precursors of GPI anchors, suggesting that the liver plasma membrane GPIs retained considerable structural homology to GPI anchors.
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PMID:Identification of glycoinositol phospholipids in rat liver by reductive radiomethylation of amines but not in H4IIE hepatoma cells or isolated hepatocytes by biosynthetic labeling with glucosamine. 132 29

Mitoxantrone, a new anti-cancer agent, was successfully prepared for Lipiodol emulsion. The mixture of Mitoxantrone and non-ionic contrast medium, Omnipaque 300, was combined with Lipiodol at the ratio of 1:2. When the ratio of Mitoxantrone and Lipiodol was 1:4, microscopic study revealed stabilized water in oil emulsion, which could release the anti-cancer agent slowly. We applied it for a case of hepatocellular carcinoma with good result. Intra-arterial infusion of this emulsion might be considered effective for treatment of hepatocellular carcinoma.
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PMID:[Successful preparation of mitoxantrone emulsion containing non-ionic contrast medium]. 132 20


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