Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0019158 (hepatitis)
 30,205 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Male and female B6C3F1 mice from 12 National Toxicology Program (NTP) 2-yr carcinogenesis studies were found to be infected with Helicobacter hepaticus. Many of the male mice from 9 of these studies had an associated hepatitis (affected studies). Helicobacter hepaticus has been reported to be associated with an increased incidence of hepatitis and hepatocellular neoplasms in the A/JCr male mouse. We attempted to determine if the data from the Helicobacter-affected NTP B6C3F1 mouse studies were compromised and unsuitable for cancer hazard identification. The incidences of neoplasms of the liver (both hepatocellular and hemangiosarcoma) but not of other organs in control male B6C3F1 mice were increased in affected studies as compared with control males from unaffected studies. The increased incidence of hepatocellular neoplasms was observed in those males exhibiting H. hepaticus-associated hepatitis. Other observations further differentiated control male mice from affected and unaffected studies. H-ras codon 61 CAA to AAA mutations were less common in liver neoplasms from males from affected studies as compared with historical and study controls. In addition, increases in cell proliferation rates and apoptosis were observed in the livers of male mice with H. hepaticus-associated hepatitis. These data support the hypothesis that the increased incidence of liver neoplasms is associated with H. hepaticus and that hepatitis may be important in the pathogenesis. Therefore, interpretation of carcinogenic effects in the liver of B6C3F1 mice may be confounded if there is H. hepaticus-associated hepatitis.
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PMID:Impact of Helicobacter hepaticus infection in B6C3F1 mice from twelve National Toxicology Program two-year carcinogenesis studies. 978 46

The death receptor Fas transduces apoptotic death signaling upon stimulation by Fas ligand and plays a key role in viral hepatitis. When hepatitis-B virus (HBV) infects hepatocytes, the Fas ligand/Fas system responds as the triggering machinery of hepatitis. However, some HBV-infected cells may circumvent Fas-mediated apoptosis and transform to hepatoma cells, as do PLC/PRF/5 hepatoma cells. Therefore, in the present study, we used PLC/PRF/5 hepatoma cells to investigate this ability to avoid Fas-mediated apoptosis. When the cells were treated with an agonistic Fas antibody, they showed resistance to Fas-mediated apoptosis. In contrast, HepG2 cells of the same hepatoma line succumbed. Caspase 3 and 8, which are essential regulators for Fas-mediated cell death, were expressed in both hepatoma cell lines, but only HepG2 cells showed activation of the caspases. A comparison study of expression of other death-associated factors between PLC/PRF/5 and HepG2 cells revealed no apparent differences. However, Far-Western blotting analysis using the Fas death domain (FDD) showed a significant difference. Molecular weight comparison and immunoblotting analysis revealed that PLC/PRF/5 cells lack the FDD-associated protein FADD. In addition, FDD-injected HepG2 cells showed a resistance to Fas-mediated apoptosis, and PLC/PRF/5 cells acquired Fas-sensitivity by FADD injection. Here, we propose that a functional absence of FADD is one of the pathways for the carcinogenesis of HBV-infected hepatocytes.
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PMID:Functional absence of FADD in PLC/PRF/5 hepatoma cells: possible involvement in the transformation to hepatoma in HBV-infected hepatocytes. 1032 Jun 34

Spontaneous renal cell tumors in totals of 223 male and female Long-Evans Cinnamon (LEC) rats of 51-120 weeks old, 157 male F344 rats of 51-120 weeks old, and 14 male Long-Evans Agouti (LEA) rats of 51-70 weeks old were examined histologically. The incidences of renal cell tumors increased with age in male and female LEC rats, but no tumors developed in F344 or LEA rats. Dilated atypical tubules of the kidneys were observed at high incidence in aged LEC rats. Copper staining of LEC rat kidneys showed a positive reaction in proximal tubules of the cortex and the outer stripe of the medulla. The renal copper concentration of LEC rats reached a peak in the period of necrotizing hepatitis with renal tubular necrosis, and was higher than that in F344 rats for up to 106 weeks. In contrast, the renal iron concentration of LEC rats was lower than that in F344 rats except in the period of necrotizing hepatitis. Long-term treatment of LEC rats with D-penicillamine, a copper-chelating agent, inhibited accumulation of copper, but not iron, in the kidneys, and inhibited the development of karyomegaly of proximal tubules and dilated atypical tubules. These results suggest that persistent copper accumulation after toxic necrosis of tubules is the major cause of spontaneous renal carcinogenesis in LEC rats.
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PMID:Role of copper accumulation in spontaneous renal carcinogenesis in Long-Evans Cinnamon rats. 1036 75

Accumulating evidence has demonstrated that aberration of the p53 tumour-suppressor gene is one of the pivotal genetic events in hepatocellular carcinogenesis. Recent reports suggest that the product of hepatitis B virus (HBV) interacts with p53 and that the hepatitis C virus (HCV) core protein reduces p53 expression. A novel p73 gene, which is related to p53, has recently been identified and mapped to chromosome 1p36.3, which is a locus of multiple tumour-suppressor genes for many cancers, including hepatocellular carcinoma (HCC) and neuroblastoma. Here, we investigated mRNA expression, allelotype and mutation of p73 in 48 HCCs obtained from untreated patients. Reverse transcriptase polymerase chain reaction (RT-PCR) revealed that p73 mRNA was expressed ubiquitously at low levels in all the tumour tissues, as well as in the adjacent normal liver tissues. The frequency of p73 loss of heterozygosity was observed in 20% of HCCs, but PCR-single strand conformation polymorphism (SSCP) analysis showed no mutations in the 48 tumours except for three types of polymorphisms. These results suggest that p73 may play a role in hepatocellular carcinogenesis in a different manner from a Knudson two-hit model. The regulatory mechanism of interaction between p73 and hepatitis viruses remains to be determined.
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PMID:Absence of mutation of the p73 gene localized at chromosome 1p36.3 in hepatocellular carcinoma. 1040 9

Hepatitis G virus (HGV) is a positive, single-strand RNA virus that has been classified in the family Flaviviridae. The 5'-untranslated region (UTR) of the HGV genome is lengthy and does not share any significant primary and secondary RNA structures with the 5'-UTR of hepatitis C virus (HCV). The internal ribosome entry site has extraordinarily weak activity. The HGV genome does not seem to encode a nucleocapside protein analogous to HCV. Blood-borne transmission is presumed to be the commonest mode of transmission of the virus. Current infection with HGV is diagnosed by detection of HGV RNA by the polymerase chain reaction (PCR), and past infection with HGV is detectable by testing anti-HGV E2. HGV is distributed worldwide, but its prevalence varies widely from one population to another. Although the prevalence of HGV in association with acute and chronic hepatitis is higher than that in the general population, further prospective studies are needed to demonstrate its relative significance in causing hepatitis and other disease. The major unresolved biological issue at the moment is its hepatotropsim and site of propagation. Recent progress demonstrates that HGV replicates in lymphocytes rather than hepatocytes. HGV may be pathogenic under special conditions, but does not influence carcinogenesis.
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PMID:GB virus C/Hepatitis G virus. 1051 74

Although human hepatocellular carcinoma (HCC) is one of the most common types of tumors in the world, the molecular mechanisms underlying hepatitis-C-related human hepatocarcinogenesis are still not clear. HCC is accompanied by virus infections in most cases, and it is suggested that hepatitis B virus and hepatitis C virus (HCV) significantly influence the oncogenic process. The persistence of inflammation following HCV infection is reportedly related to carcinogenesis, and the mechanism of chronic inflammation has been approached by taking viral, immunologic, cytokine and apoptotic responses into consideration. With the progress made in molecular biology, the functional abnormality of oncogenes/tumor suppressor genes has been identified and, apart from the p53 gene, involvement of the IGF-II gene has also been described recently. Furthermore, it has been suggested that uncontrolled proliferation of cancer cells might be based on abnormal regulation of intracellular signal transduction pathways. Here we review the cutting edge of molecular hepatitis C virology in terms of virus-cell interactions, which may contribute to the development of human HCCs. We also discuss the recent progress made in the molecular and cell biology of human hepatocarcinogenesis.
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PMID:Hepatitis C virus and hepatocarcinogenesis. 1051 76

Multifocal carcinogenesis is caused by a persistent infection of hepatitis viruses, and is considered to be the main cause of post-operational recurrences of hepatocellular carcinoma. It has been generally believed that a single therapeutic modality (including resection therapy) cannot improve the survival rate. In this paper, we describe the efficacy of microwave coagulation therapy and its indications based on an analysis of cases experienced at our institution over a 10-year period. We compared the background factors, recurrence rate, and survival rate of various therapies, and concluded that microwave coagulation therapy is highly effective for tumor coagulation and necrosis. Microwave coagulation therapy is also technically easier than a surgical operation, has fewer complications, and results in an equally good survival rate when compared to hepatectomy. Due to these intrinsic advantages, microwave therapy is useful not only as a treatment after recurrence, but also as a primary therapy of small liver tumors. When the detection rate for small liver tumors increases, microwave coagulation therapy will start to play an even more important role in the treatment strategy for hepatocellular carcinomas as a less invasive option, in addition to laparotomic and percutaneous/laparoscopic surgeries.
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PMID:[Indication of percutaneous microwave coagulation therapy for hepatocellular carcinoma]. 1056 Mar 71

The study of human hepatitis, particularly in Asia, where the incidence rate has been the highest in the world, has contributed greatly to the understanding of carcinogenesis of the liver and related diseases. In this article, the history of research on hepatitis viruses and hepatocellular carcinoma (HCC) and the successful prevention of vertical transmission of hepatitis B virus (HBV) in Japan are reviewed, focusing on the studies that resulted in the identification of vertical transmission of HBV infection and the association of HBV-sustained infection and HCC. The vaccination trials for preventing HBV vertical transmission and the fruitful outcome of the nationwide vaccination strategy in Japan, on the basis of "selective" immunization by using anti-HBs immunoglobulin (HBIG) and HB vaccine, are highlighted. Ongoing studies on the mechanisms underlying hepatocarcinogenesis induced by viruses, e.g., the roles of viral proteins and inflammation, are also reviewed, and prospects for the control of HCC are discussed.
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PMID:Viral hepatitis and hepatocellular carcinoma prevention strategy in Japan. 1059 31

The relationship between multicentric occurrence of hepatocellular carcinoma (HCC) and the histology of noncancerous hepatic tissue was investigated in 252 patients infected with hepatitis C virus (HCV) and surgically treated for HCC. One type of multicentric HCC had at least one tumor consisting of well-differentiated HCC, together with moderately or poorly differentiated HCC located in a separate region. The other type had an area of well-differentiated component around HCC with less differentiation in all occurrences. Noncancerous hepatic tissues were assessed using a histologic activity index score. Serum alanine aminotransferase (ALT) activity, the concentration of type 4 collagen, the grading score (severity of active hepatitis), and the staging score (degree of fibrosis) were significantly higher in patients with multicentric HCCs than in those without them. Platelet count was significantly lower in patients with multicentric HCCs. The prevalence of multicentric HCCs increased as the grading score and staging score increased. On univariate analysis, a low platelet count and high grading and staging scores were risk factors for multicentric HCCs. A high ALT activity and a high concentration of type 4 collagen tended to be risk factors. On multivariate analysis, high grading score and high staging score were independent risk factors. These findings indicate that active hepatitis and extensive fibrosis are responsible for the development of multicentric HCCs. Measurement of platelet count, ALT activity, and the concentration of type 4 collagen, and histologic assessment of noncancerous hepatic tissue provide information useful for estimation of the potential for multicentric carcinogenesis.
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PMID:Relationship between multicentric occurrence of hepatocellular carcinoma and histology of noncancerous hepatic tissue in patients with chronic hepatitis C. 1059 35

Little data are available regarding the effects of hepatitis virus serostatus and the severity of coexisting chronic inflammation on intrahepatic recurrence after hepatectomy for hepatocellular carcinoma (HCC). We investigated the extent to which these factors modified the prognosis of hepatectomized patients. A total of 274 patients treated in the period January 1981 to December 1996 were divided into three groups: antihepatitis C-positive (HCV; n = 144), hepatitis B surface antigen-positive and HCV antibody (Ab)-negative (HBsAg; n = 106), and HBsAg-negative and HCV Ab-negative (NBNC; n = 20). Positivity for HBV-related antibody in the HCV group was 76%. Histologic grading of inflammatory activity from coexisting hepatitis was determined according to Knodel's histological activity index (HAI) scoring system. Post-hepatectomy crude survival rates and disease-free survival (DFS) rates were compared, according to tumor characteristics, between the three groups. In the patients overall and also in the patients with a single nodular HCC, the HCV group had significantly higher HAI scores and preoperative serum aspartate aminotransaminase (AST) levels than the other two groups. When the patients were limited to those with a single nodular HCC, the crude survival was similar in the three groups with comparable tumor characteristics; however, the DFS was different (NBNC > HBsAg > HCV). When the patients were further limited to those with a single nodular HCC without microscopic extracapsular spread, in whom removal of the tumor was expected to be microscopically complete, the difference in the DFS became more marked. Irrespective of the viral serostatus, better crude and disease-free survivals were observed in the patients with lower AST levels (< or =50 IU/ 1) than in those with higher AST levels (>50IU/l). In contrast, there were no differences in survivals and HAI scores according to the presence or absence of HBV-related antibody in the HCV group. From our univariate analysis, we can conclude that the severity of virally induced inflammation, which was well correlated with viral serostatus, may be a factor that affects intrahepatic recurrence, which is more likely to originate from metachronous carcinogenesis. Prior co-infection of HBV in HCV patients may not be an adverse risk factor for intrahepatic recurrence.
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PMID:Viral serostatus and coexisting inflammatory activity affect metachronous carcinogenesis after hepatectomy for hepatocellular carcinoma. A further report. 1075 90


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