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)

Rare benzo[a]pyrene-resistant clones were previously isolated from the mouse hepatoma cell line, Hepa-1 (Hepa1c1c7), and shown to be deficient in induction of CYP1A1 mRNA by ligands for the aryl hydrocarbon receptor (AHR). Clones belonging to complementation group B were shown to have reduced levels of ligand binding to AHR. It is shown here that all 15 independently derived B clones analyzed had much reduced levels of AHR mRNA, but in each case, the mRNA was normal in size. Infection of B clones with a retroviral expression vector for AHR restores CYP1A1 inducibility (although viral AHR expression is progressively silenced and CYP1A1 expression progressively diminishes as the cells are maintained in culture). Treatment of the B clones with the histone deacetylase inhibitors sodium butyrate or trichostatin A restores AHR expression and also restores CYP1A1 inducibility to nearly 100% of the cells in the treated cultures. Fusion of a representative B clone with a rat hepatoma cell line restores expression to the mouse AHR gene encoded by the B clone's genome. These results demonstrate that the loss of CYP1A1 inducibility in B clones is probably totally ascribable to their reduced levels of AHR and that the clones are most probably not mutated in the AHR gene but are deficient in its expression. The evidence suggests that the reduction in expression of mRNA encoded by the endogenous AHR gene in the B clones is not due to an epigenetic alteration in chromatin structure but that the clones are probably defective either in a transcription factor for the AHR gene or in a protein required for generating an open chromatin configuration over the gene.
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PMID:Basis for the loss of aryl hydrocarbon receptor gene expression in clones of a mouse hepatoma cell line. 896 65

The influence of the hepatitis C virus (HCV)-genotype on liver disease severity was evaluated in 429 consecutive patients with chronic hepatitis C, including 109 with cirrhosis who were followed up prospectively, allowing for the assessment of the role of the HCV-genotype on disease outcome and on the development of hepatocellular carcinoma (HCC). HCV-1 was detected in 147 (46%) patients without cirrhosis and in 47 (43%) with cirrhosis (P: not significant), being mainly HCV-1b. HCV-2 was found in 103 (32%) cases without cirrhosis and in 30 (27.5) with cirrhosis (P: not significant), being mainly HCV-2a. HCV-3 was detected in 32 (10%) patients without cirrhosis and in 2 (2%) with cirrhosis (P < 0.005). Infection with more than one genotype (HCV-1/HCV-2 and HCV-1/HCV-3) was observed only in cirrhotic patients (6 of 109; 5.5%). During a mean follow-up of 67 +/- 22 months, 21 (19%) patients with cirrhosis showed worsening in Child's stage, 5 (4.5%) underwent liver transplantation, 23 (21%) developed HCC, and 24 (22%) died of complication of liver disease; the overall incidence of at least one of these events was 38.5%. By the Kaplan-Meier method and log-rank test, the cumulative probability of developing each or at least one of the above events did not differ in relation to the genotype of infecting HCV, apart from patients with mixed genotype infection who showed a significantly higher incidence of death (P < .05). These data indicate that HCV-genotypes do not have a significant effect on the severity and outcome of liver disease in patients with chronic HCV-infection. Patients with cirrhosis who are also infected by HCV-1 and HCV-2 had a similar prognosis and progression to HCC, while patients infected by more than one genotype showed the most unfavorable course of disease.
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PMID:Lack of correlation between hepatitis C virus genotypes and clinical course of hepatitis C virus-related cirrhosis. 898 92

Hepatitis C is becoming the main cause of cirrhosis and primary liver carcinoma. Infection by hepatitis C virus (HCV) generally induces an asymptomatic acute hepatitis. HCV infection becomes chronic in about 80% of cases. In a minority of the subjects, chronic HCV infection is asymptomatic with persistent viremia and normal liver tests. These asymptomatic subjects have minimal liver histologic lesions and a good prognosis. In a majority of the subjects, chronic HCV infection is associated with chronic hepatitis with increased serum transaminases levels. Among the patients with chronic hepatitis, the majority have a mild liver disease with a moderate increase in serum transaminases levels and, at liver histology, minimal lesions; a minority (about 20%) have a more severe liver disease and will develop cirrhosis after 5 to 20 years. In patients with HCV related cirrhosis, the incidence of hepatocellular carcinoma is high (around 5% per year). The factors influencing the evolution of HCV infection are not known. Alcohol is certainly an important factor which increases the risk of development of fibrosis then cirrhosis. Virus related factors, such as genotype and level of replication, might also be important. Autoimmune diseases have been reported in association with hepatitis C. HCV infection is a major cause of mixed cryoglobulinemia associated with vasculitis or glomerulonephritis. A relationship between HCV and auto-immune diseases such as thyroiditis or Gougerot syndrome has been suggested but not demonstrated. HCV infection is frequent in patients with porphyria cutanea tarda; in these patients, HCV related liver disease might trigger the expression of the metabolic disease.
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PMID:[Clinical picture and evolution of hepatitis C]. 899 8

Infection with hepadnaviruses and exposure to aflatoxin B1 (AFB1) are considered major risk factors in the development of hepatocellular carcinoma (HCC) in humans and in animals. A high rate of mutations in the p53 tumor suppressor gene in hepatocellular carcinomas of predominantly hepatitis B virus (HBV) carrier patients has been recently related to dietary aflatoxin. Another member of the hepadnavirus family, the woodchuck hepatitis virus (WHV), infects woodchucks in a manner similar to that of HBV in humans. Therefore, it was of particular interest to determine whether the p53 gene in woodchuck HCCs associated with hepadnavirus infection and with exposure to AFB1 is affected in the same manner as in human HCCs. By direct PCR-sequencing, we analyzed exons 4-9 of the p53 gene in 13 HCCs from 12 woodchucks (two uninfected, ten WHV carriers). Six WHV carrier and two uninfected woodchucks were treated with AFB1. None of the analyzed HCC samples exhibited mutations, either in p53 gene exons 4-9, or in splicing donor-acceptor sites. The present data are consistent with our previous study that indicated a low rate of p53 mutations in HCCs of AFB1-treated ground squirrels, either infected or not infected with ground squirrel hepatitis virus, and in WHV carrier woodchucks not exposed to AFB1. Overall, our findings indicate that in woodchucks and in ground squirrels exposure to aflatoxin may affect the development of p53 mutations less than in humans.
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PMID:Absence of mutations in the p53 tumor suppressor gene in woodchuck hepatocellular carcinomas associated with hepadnavirus infection and intake of aflatoxin B1. 900 7

Infection with HGBV-C was surveyed in 286 patients with chronic liver disease. HGBV-C RNA was detected in 19 patients (6.6%), by nested RT-PCR with 5'UTR-derived primers. There were no appreciable differences in clinical and virological features between patients with and without HGBV-C RNA in serum. HGBV-C RNA was detected in three of 83(4%) patients with HBV infection, 15(8%) of 188 patients with HCV infection, and one of 12(8%) patients without evidence of ongoing infection with HBV or HCV, suggesting that the contribution of HGBV-C to non-B non-C hepatitis would not be high. HGBV-C RNA was detected more frequently in the patients with liver cirrhosis or hepatocellular carcinoma than in those with chronic hepatitis. This could reflect a possible role of HGBV-C in aggravating liver disease in co-operation with the other hepatitis viruses.
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PMID:[HGBV-C infection in patients with chronic liver disease]. 908 59

Infection with putative non-A to E hepatitis virus, designated GB virus C (GBV-C), was surveyed in 286 patients with chronic liver disease in Japan. RNA of GBV-C was detected, by reverse-transcription polymerase chain reaction with nested primers from the 5'-noncoding region, in 19 patients (6.6%) at a frequency higher (P < 0.001) than in three of 275 (1.1%) normal controls. It was detected in three of 83 (4%) patients with hepatitis B virus infection, 15 of 188 (8%) patients with hepatitis C virus infection, and one of 12 (8%) patients without evidence of ongoing infection with hepatitis B or C virus. GBV-C RNA was detected in nine of 186 (5%) patients with chronic hepatitis aged 51.2 +/- 13.3 years, six of 64 (9%) with liver cirrhosis aged 62.9 +/- 11.4 years, and four of 36 (11%) with hepatocellular carcinoma aged 62.0 +/- 11.1 years. Nucleotide sequences of 100 base pairs in the helicase region of GBV-C isolates from the 19 patients varied up to 21%, while sequences of 33 deduced amino acids were conserved and differed only by up to 6%. These results indicate that infection with GBV-C in patients with non-B, non-C chronic liver disease would not be frequent, although the sensitivity of the detection method could be improved. Coinfection of GBV-C with hepatitis B or C virus, as well as the duration of infection, might accelerate the progression of chronic liver disease.
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PMID:Infection with GB virus C in patients with chronic liver disease. 913 80

Using recombinant adenoviral vectors and a dominant negative mutant of HNF-4, we have examined the contribution of hepatocyte nuclear factor 4 (HNF-4) to endogenous apolipoprotein AI and CIII mRNA expression. Overexpression of HNF-4 leads to a 7.4-fold increase in apolipoprotein CIII expression, while infection with the dominant negative mutant of HNF-4 reduces the level of apolipoprotein CIII mRNA by 80%, demonstrating that endogenous HNF-4 is necessary for apolipoprotein CIII expression. Experiments using the hepatoma cell lines, HepG2 and Hep3B, indicate that HNF-4 is also involved in the regulation of apolipoprotein AI expression in these lines. However, the effect of HNF-4 on apolipoprotein AI expression is much more dramatic in cell lines derived from intestinal epithelium. Infection of the intestinal-derived cell line IEC-6 with the HNF-4 adenovirus resulted in a greater than 20-fold increase in the level of apolipoprotein AI mRNA. These results indicate that HNF-4 does regulate apolipoprotein AI and CIII mRNA expression and suggest that HNF-4 is critical for intestinal apolipoprotein AI expression.
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PMID:Utilization of recombinant adenovirus and dominant negative mutants to characterize hepatocyte nuclear factor 4-regulated apolipoprotein AI and CIII expression. 915 49

We performed a case-control study to assess the association of hepatocellular carcinoma (HCC) with hepatitis B virus (HBV) and hepatitis C virus (HCV) infection and alcohol drinking. We recruited as cases 172 subjects with an initial diagnosis of HCC, who were admitted to the two major hospitals in the province of Brescia, northern Italy, and 332 subjects, sex-, age-, and hospital-matched, who were admitted to the Departments of Ophthalmology, Dermatology, Urology, Cardiology, and Internal Medicine, as controls. Of the HCC cases, 23.8% were positive for HBsAg and 37.8% for HCV RNA; among the controls, 5.4% were positive for HBsAg and 4.8% for HCV RNA. History of heavy alcohol intake (>80 g of ethanol per day for at least 5 years) was found among 58.1% of the cases and among 36.4% of the controls. The relative risks (RRs) for HBsAg, HCV RNA positivity, and heavy alcohol intake were, respectively: 11.4 (95% confidence interval: 5.7-22.8), 23.2 (95% confidence interval: 11.8-45.7), and 4.6 (95% confidence interval: 2.7-7.8). Positive interactions (synergisms) between both HBsAg positivity and HCV RNA positivity and heavy alcohol intake were found, suggesting more than additive effects of viral infections and alcohol drinking on the risk of HCC. Infection with HCV genotype 1b showed a higher risk than type 2 (RR = 2.9; 95% confidence interval: 0.9-10), suggesting a major role for the former type in causing HCC. On the basis of population attributable risks (AR), heavy alcohol intake seems to be the single most relevant cause of HCC in this area (AR: 45%), followed by HCV (AR: 36%), and HBV (AR: 22%) infection.
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PMID:Hepatitis B and C virus infection, alcohol drinking, and hepatocellular carcinoma: a case-control study in Italy. Brescia HCC Study. 930 86

Several epidemiological studies suggest that chronic alcoholics are at risk of viral infections. Clinical and basic research has demonstrated that alcohol not only worsens the natural history of chronic viral hepatitis, but also seems to interact with the viral replication cycle leading to an unusual serum virological profile and/or modification in the serum concentration of viral particles. Infections with hepatitis B and C viruses are a major risk for the development of hepatocellular carcinoma in excessive drinkers who should be protected against these viruses.
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PMID:ESBRA 1997 Award lecture: relationship between excessive alcohol drinking and viral infections. 963 45

To examine the association of apolipoprotein (apo) E with nascent hepatic lipoproteins we have prepared stable transfectants of the rat hepatoma cell line McA RH7777 expressing the human apoE3 cDNA. When the nascent lipoproteins secreted from control cells were separated on fast protein liquid chromatography (FPLC) columns, rat apoE was detected in the very low density (VLDL) and high density lipoprotein (HDL) fractions, while rat apoA-I was found in the HDL and lipoprotein free fractions. Human apoE was also associated with the VLDL and HDL particles secreted from the transfected McA RH7777 cells. Expression of human apoE resulted in a significant decrease in the amount of rat apoA-I associated with the lipoprotein particles. Rat apoE was also displaced, but to a lesser extent. Infection of McA RH7777 cells at different multiplicities of infection with recombinant adenoviral vector containing the human apoE cDNA indicated that rat apoA-I was decreased in the HDL fractions at lower levels of expression of human apoE than was rat apoE. The HDL particles were further examined by immunoblotting of nondenaturing gradient gels and by non-denaturing immunoprecipitation. The results indicate that the high density lipoprotein (HDL) particles are heterogeneous in size and apolipoprotein composition with the majority of the rat and human apolipoproteins being located on different particles. These results suggest that the profile and concentration of HDL apolipoproteins produced in hepatocytes influences the assembly of the various subsets of secreted HDL.
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PMID:Association of human apolipoprotein E with lipoproteins secreted by transfected McA RH7777 cells. 968 39


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