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)

The LEC (Long-Evans cinnamon) rat is a mutant strain displaying hereditary hepatitis and spontaneous hepatocellular carcinoma, and shows abnormal hepatic copper accumulation similar to that occurring in Wilson's disease. We evaluated the iron metabolism of LEC rats compared to LEA (Long-Evans agouti) rats. Hepatic iron and ferritin concentrations were remarkably increased depending on age in LEC rats but not in LEA rats. Increased hepatic iron is normally associated with decreased serum transferrin and total iron binding capacity in hepatic iron overload. In LEC rats, however, both serum transferrin and total iron binding capacity increased with increasing hepatic iron. This increase of serum transferrin and hepatic iron may be an additional important factor contributing to liver injury in LEC rats.
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PMID:Abnormal hepatic iron accumulation in LEC rats. 838 76

Acute hepatitis spontaneously develops in the Long-Evans Cinnamon rat at the age of 4 mo, and eventually hepatocellular carcinoma develops after the chronic hepatitis that persists for over a year. Previously, abnormal copper accumulation was found in the livers of Long-Evans Cinnamon rats from birth, and it was reported that short-term administration of D-penicillamine, a copper-chelating agent, prevented acute hepatitis in Long-Evans Cinnamon rats. In this study we investigated whether long-term administration of D-penicillamine could also prevent chronic hepatitis and subsequent hepatocellular carcinoma in Long-Evans Cinnamon rats. During long-term observation, which was continued from 11 to 70 wk after birth, no elevation of serum transaminase levels was observed in the Long-Evans Cinnamon rats treated with D-penicillamine. Moreover, no histological changes characteristic of the chronic hepatitis were observed in D-penicillamine-treated Long-Evans Cinnamon rats, which were killed at 70 wk of age. Furthermore, placental glutathione S-transferase-positive foci, described as a marker for preneoplastic lesions in the liver, were not detected, and thus hepatocarcinogenesis was completely prevented in D-penicillamine-treated Long-Evans Cinnamon rats. We also found that the amount of 8-hydroxy-deoxyguanosine, one of oxidative DNA damage products in the liver, was decreased in the Long-Evans Cinnamon rats treated with D-penicillamine. These findings suggest that a process of the prolonged liver-cell injury and regeneration was essential for spontaneous development of hepatocellular carcinoma in Long-Evans Cinnamon rats with abnormal copper metabolism.
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PMID:Prevention of spontaneous hepatocellular carcinoma in Long-Evans cinnamon rats with hereditary hepatitis by the administration of D-penicillamine. 839 59

Certain features of Wilson's disease (WD) in Asia have been found to be different from those in other continents. The higher prevalence rate in Japan is presumably due to a higher consanguinity rate. In Chinese there is a tight linkage between WD and two gene loci for esterase D and retinoblastoma in the long arm of chromosome 13. The high proportion of patients with hepatic presentation accounts for early onset of WD in the Japanese and Chinese series. Skeletal involvement, leg hyperpigmentation, dark complexion, amenorrhea, epileptic seizures, and cerebral white matter degeneration are relatively more common among WD patients in Asia. Excessive copper in the liver appears to have a protective effect against hepatocellular carcinoma and type B hepatitis. Electrophysiological studies suggest widespread functional disturbances of the CNS in WD. Side-effects from penicillamine are rather frequent and often lead to interruption of the therapy. Trien is found to be effective without adverse reactions. Oral zinc therapy may be a suitable alternative for long-term management of WD patients in developing Asian countries.
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PMID:Geographic variations in Wilson's disease. 841 43

Long-Evans Cinnamon (LEC) rats are autosomal recessive mutants that develop hepatitis and hepatocellular carcinoma. Because copper accumulates in the livers of these rats, and some of their clinical and pathological features are similar to those of patients with Wilson's disease, LEC rats are proposed as an animal model of Wilson's disease. It has been thought that unbound copper generates free radicals, which act as hemolytic and hepatocytotoxic agents. To examine the effects of vitamin E as an antioxidant on hereditary hepatitis in LEC rats, we fed 3-week-old rats for 25 weeks either vitamin E-deficient, control, or vitamin E-supplemented diets which contained < 0.01 mg of total tocopherols, 2 mg of d,l-alpha-tocopheryl acetate (2 I.U.), and 58.5 mg of d,l-alpha-tocopheryl nicotinate (50 I.U.), respectively, per 100 mg of feed. In males, body weight loss was first observed in the vitamin E-deficient group, and mean ages at which jaundice occurred were in the order: deficient younger than control younger than supplemented groups. The ages when plasma glutamic oxaloacetic transaminase and glutamic pyruvic transaminase activities began to increase sharply and peaked followed the same order. Thus, it is likely that free radicals are involved in jaundice and hepatitis in LEC male rats, and they are a model for studying the relationship of copper, free radicals, and hepatitis. Conversely, in females, no apparent differences in clinical and biochemical changes were observed among the three groups. Causes for the discrepancy between the sexes remain to be clarified.
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PMID:Effects of dietary vitamin E on clinical course and plasma glutamic oxaloacetic transaminase and glutamic pyruvic transaminase activities in hereditary hepatitis of LEC rats. 845 79

We report changes in free radical-metabolizing enzymes and the increased generation of lipid peroxides associated with extreme metal accumulation in the liver of the Long-Evans with cinnamon-like coat color (LEC) rat, a new mutant strain displaying hereditary hepatitis and subsequent hepatocellular carcinoma. The activity of free radical-metabolizing enzymes and lipid peroxides, and the concentration of metal in the liver were determined sequentially after birth. Mn-superoxide dismutase activity significantly increased immediately after the onset of hepatitis in LEC rats, whereas no remarkable change was observed in control rats. Cu, Zn-superoxide dismutase activity in LEC rats was similar to that in control rats. Glutathione reductase activity increased, while glutathione peroxidase activity was lower in LEC rats than in control rats throughout the observation periods. Lipid peroxides, estimated by thiobarbituric acid reaction, also increased 4- to 5-fold immediately after the onset of hepatitis in LEC rats. Copper concentration was 30- to 50-fold higher in the liver of LEC rats than in control rats, and the iron content also increased significantly before and after the onset of hepatitis. These findings suggested that an oxidant injury generated by toxic metals could be one of the factors responsible for hepatocellular damage in this unique hereditary hepatitis.
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PMID:Changes in free radical-metabolizing enzymes and lipid peroxides in the liver of Long-Evans with cinnamon-like coat color rats. 857 34

The significance of the biochemical and nutritional roles of trace elements is widely recognized, since metals are found as constituent components of many metalloproteins and metalloenzymes. Some trace elements such as copper act as cofactors against hepatic fibrosis in chronic liver diseases, particularly in the biosynthesis of collagen. As the disease progress from chronic hepatitis to liver cirrhosis, serum calcium, magnesium, phosphorus and zinc concentrations decrease, while the copper concentration increases. In the patients with hepatocellular carcinoma, serum concentrations of trace elements are similar to those of liver cirrhosis. In the patients with acute hepatitis, serum calcium, magnesium and zinc concentrations decrease, while phosphorus, iron and copper concentrations decrease. These trace element abnormalities may reflect such pathological conditions as liver dysfunction, cholestasis, hepatic fibrosis or liver regeneration.
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PMID:[Liver diseases and essential trace elements]. 858 11

Proliferation of preexisting bile ducts, ductular metaplasia of hepatocytes and proliferation and differentiation of liver stem cells are discussed in the pathogenesis of neoductular structures in the liver. Under the condition of experimental bile duct obstruction and in extrahepatic bile duct stenosis neoductular structures are first the result of proliferation and sprouting of preexisting ducts and cholangioles. Especially in later stages of cholestasis but also in other chronic progredient liver diseases such as chronic alcoholic liver disease and chronic active hepatitis periportal hepatocytes may show a phenotypic shift towards ductular epithelia. In postnatal liver diseases hepatocytes first express keratin 7 and later keratin 19 during ductular transdifferentiation. This is in contrast to embryonal cholangiogenesis. In alpha-1-antitrypsin-deficiency, hemochromatosis, Wilson's disease, and chronic active hepatitis B cellular deposites typically located in hepatocytes such as alpha-1-AT, siderin, copper, HBs-Ag, and HBc-Ag can also be found in neoductular cells close to hepatocytes. These deposites seem to be retained during the ductular transdifferentiation of hepatocytes. Expression of bile duct-type integrin subtypes and TGF beta 1 in neoductular cells are involved in the changing parenchymal/mesenchymal interplay during neoductogenesis, resulting in periductular basal membrane and periductular fibrosis. In FNH the ductular transdifferentiation of hepatocytes is integrated in the histogenesis of micronodules and portal tract equivalents of these tumor-like lesions. Ductular structures in hepatoblastomas and especially in combined hepatocellular and cholangiocarcinomas (CHCC) may reflect the common embryologic derivation of hepatocytes and biliary epithelia. Non-neoplastic liver tissue in resection specimens of our CHCC showed a lower rate of cirrhosis, and a significantly higher Ki 67-LI of neoductular cells compared to liver tissue in resection specimens of HCC and liver metastases. 3 of 10 CHCC had developed in alpha-1-AT-deficiency, in which this protease-inhibitor was predominantly retained in periportal hepatocytes. These findings in non-neoplastic tumor-bearing liver tissue suggest that CHCC include a special histogenic type of primary liver carcinoma which in analogy to some experimental liver tumors might develop from periportal parenchymal cells.
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PMID:[Hepatic neoductules]. 860 Jun 93

Formation of etheno-DNA adducts in the liver was investigated in Long Evans cinnamon (LEC) rats, a Long Evans strain with hereditary abnormal copper metabolism, which develop spontaneous hepatitis and later hepatocellular carcinoma. Using an ultrasensitive immunoaffinity/32P-postlabeling assay (J. Nair et al., Carcinogenesis, 16: 613-617, 1995), the etheno adducts 1,N6-ethenodeoxyadenosine (epsilon dA) and 3,N4-ethenodeoxycytidine (epsilon dC) were measured in the liver of 7-, 18-, 30-, and 87-week-old LEC rats. Levels were highest in the liver of 18-week old rats 85 +/- 17 (epsilon dA) and 85 +/- 30 (epsilon dC) adducts per 10(9) parent nucleotides, and the increase in the levels of etheno adducts was age dependent. Age-matched Long Evans agouti rats, a tumor-free sibling line of LEC rats, had much lower levels of both etheno adducts. Etheno adduct levels in LEC rats were well correlated with the hepatic copper levels, and peak adduct levels coincided with the age of commencement of fulminant hepatitis. Our results demonstrate for the first time a copper- and age-dependent formation of highly miscoding etheno-DNA adducts in the liver of LEC rats. These adducts are formed from lipid peroxidation products (F. El-Ghissassi et al., Chem. Res. Toxicol., 8: 273-283, 1995) and thus could arise in the liver of LEC rats from oxygen radicals generated by copper-catalyzed Fenton-type reactions. Etheno-DNA adducts along with other oxidative DNA base damages may thus be involved in liver carcinogenesis in LEC rats.
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PMID:Copper-dependent formation of miscoding etheno-DNA adducts in the liver of Long Evans cinnamon (LEC) rats developing hereditary hepatitis and hepatocellular carcinoma. 864 Aug 12

In view of the current speculation regarding the possible role of reactive oxygen species (ROS) in apoptosis, both under physiological conditions and in response to chemicals that promote their intracellular formation, the present investigation was undertaken to examine whether DNA fragmentation during oxidative stress results from endonuclease activity (apoptosis) or from direct attack by ROS. We report that the incubation of HepG2 cells (a human-derived hepatoma cell line) with the copper(II) complex of 1,10-phenanthroline, CuII(OP)2, results in internucleosomal DNA fragmentation, which is widely recognized as being a hallmark of apoptosis. DNA fragmentation did not occur at low temperature, but activity was restored by the addition of ascorbic acid. It is proposed that DNA fragmentation results from the direct attack of hydroxyl radicals upon DNA. Hydroxyl radicals are produced from oxygen by the redox-cycling of CuII(OP)2, which is supported by metabolic processes at normal temperature. At low temperature ascorbic acid provides an artificial cellular reducing environment, thereby restoring hydroxyl radical formation. These findings were confirmed by the detection of internucleosomal DNA fragmentation following the exposure of isolated chromatin to a biomimetic CuII(OP)2 redox-cycling system. We conclude that DNA laddering, the widely employed hallmark of apoptosis, is not unique to endonuclease activity and may also result from direct attack upon DNA by the hydroxyl radical.
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PMID:Research communication copper-1,10-phenanthroline induces internucleosomal DNA fragmentation in HepG2 cells, resulting from direct oxidation by the hydroxyl radical. 869 54

We applied a multivariate analysis to a large series of serum biochemical tests in an attempt to identify a function that could efficiently discriminate cirrhosis from hepatocellular carcinoma (HC). We analyzed two successive temporal cohorts (1987-90; 1991-94) of HC and cirrhotic patients, all histologically classified (first cohort: 69 cirrhosis and 39 HC; second cohort: 66 cirrhosis and 38 HC). Using data from the first temporal cohort of patients, we obtained a discriminant function based on seven serum analytes: alpha-fetoprotein, the hepatic isoenzyme of alkaline phosphatase, lactate dehydrogenase isoenzyme 5, total gamma-glutamyltransferase (GGT), GGT isoforms complexed with low-density lipoprotein, aspartate aminotransferase, and copper. The same panel of analytes emerged when the second cohort was tested and also when both cohorts were tested together. In the two successive cohorts (total, 212 patients) with a prevalence of cirrhosis vs HC of approximately 2:1, the discriminant function correctly classified 93% of cases, the highest percentage of correct classification of the two diseases obtained so far by laboratory approaches. Validation with the jackknife reallocation statistical algorithm confirmed these results. In addition, of six patients with liver cirrhosis for whom we had the opportunity of following up and observing the evolution to HC, five were classified as HC at diagnosis by the multivariate discriminant analysis; i.e., discriminant analysis provided a diagnostic lead time of 6-12 months over histology. This discriminant function, based on easy-to-perform serum biochemical tests, may help solve a fundamental problem of differential diagnosis in the evolution of chronic liver diseases from cirrhosis to HC.
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PMID:Differential diagnosis between hepatocellular carcinoma and cirrhosis through a discriminant function based on results for serum analytes. 869 87


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