Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0019163 (hepatitis B)
 38,309 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In nonmalignant disease, there have been two mechanisms implicated in the association of HLA antigens with disease. In ankylosing spondylitis, evidence is accumulating for cross tolerance between a bacterial antigen and the HLA-B27 antigen; while in the autoimmune diseases, the involvement of an abnormal immune response gene, associated with A1/B8 haplotype, is strongly suspected. The same haplotype has also been associated with recovery from hepatitis B infection and survival of patients with Hodgkin's disease and acute myeloid leukaemia. At present, there are no techniques to study directly immune response genes in man and so these observations are still strictly academic. However, with increasing interest in the use of immunotherapy in cancer and the demonstration in mice that the major histocompatibility system may be the site of action of soluble mediators of immune memory, understanding the mechanisms of action of the HLA associated resistance factors may enable a more rational approach to immunotherapy in man.
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PMID:The HLA system and immunological defence against cancer: a review. 63 42

Our knowledge of the cellular changes that lead to liver cell carcinoma in humans is limited by proper and necessary ethical restriction on clinical research. We know rather more about risk factors, the most important of which is cirrhosis, it seems that both the causative agent and the time of duration of the cirrhotic process are relevent to the magnitude of this risk. According to present knowledge, alpha1-antitrypsin deficiency, alcoholism, naturally occurring carcinogens, drugs, and the hepatitis B virus seem to carry the greatest risk of cancer developing in a cirrhotic patient. Cirrhosis, however, is not an essential prerequisite, and some or possibly all of these agents can also induce cancer without cirrhosis. Bile duct carcinoma commonly follows infestation with liver flukes. Cirrhosis is usually absent but duct epithelial hyperplasia is present prior to the development of cancer. Many cellular changes have been observed in patients and among populations considered to be at risk from liver cancer. Of these, liver cell dysplasia is the most striking and studies of its prevalence, natural history, and association with cirrhosis suggest that it is a precancerous change.
Cancer Res 1976 Jul
PMID:Precursor lesions for liver cancer in humans. 77 94

Average annual age-adjusted mortality rates per 100,000 from primary hepatic carcinoma (PHC) among males for 1971-1973 in the urban and rural areas of the 9 geographical regions of Greece were estimated. Hepatitis-B surface antigen (HBsAg) prevalence by region and area was evaluated in a sample of 22,844 Greek Air Force recruits from all parts of the country. Mortality from PHC was found significantly higher in urban areas (28-30 vs. 18-81) whereas prevalence of HBsAg was higher in rural areas (5-3% vs. 3-90%). Nevertheless further statistical analysis showed that there is a strong correlation between HBsAg prevalence and mortality from PHC, which is higher in rural (r = + 0-88) than in urban (+ 0-57) areas. The latter findings indicate that hepatitis B infection and PHC may be causally related.
Br J Cancer 1976 Jul
PMID:Geographic correlation between mortality from primary hepatic carcinoma and prevalence of hepatitis B surface antigen in Greece. 95 17

Peers and Linsell (1973) demonstrated a significant association between the incidence of primary liver cancer and ingested aflatoxin in a study in the Muranga district of Kenya. A study of hepatitis B antigen in the same district showed no significant differences between the low altitude area, with a relatively high incidence of primary liver cancer, and the high altitude area with a lower incidence of the tumour. Current evidence is more in favour of aflatoxin playing an important role in the aetiology of primary liver cancer but hepatitis B antigen may play an ancillary role.
Br J Cancer 1975 May
PMID:Hepatitis Bs antigen and liver cancer: A population based study in Kenya. 115 31

A case/control study has been carried out to determine by radioimmunoassay and passive hemagglutination techniques the prevalence of hepatitis B surface antigen (HBsAg) and antibody (anti-HBs) in patients with primary liver cancer (PLC) and age/sex-matched hospital controls with cancers of other sites (OCC) and similarly matched controls without cancer (NCC). HBsAg was found in 61.2% of 165 cases of PLC as compared to 11.7% of 328 NCC. The frequency of HBsAg in PLC patients was significantly higher (72.2%) in those with detectable alpha fetoprotein as compared to those without (40.3%). There was no difference in the frequency of HBsAg in PLC patients with and without accompanying cirrhosis. No significant difference in potential hepatitis exposure history was found in the three study groups.
Int J Cancer 1975 Sep 15
PMID:A case/control study of the association between primary liver cancer and hepatitis B infection in Senegal. 117 99

Patients with decompensated liver cirrhosis (n 1441) and those with post-transfusion hepatitis (n 343), whose medical expenses were subsidized by the Aichi Prefectural Government, were followed up for three years by record linkage with the Aichi Cancer Registry. During the follow-up period, 122 incident cases of liver cancer were identified. Compared with the general population, patients with decompensated liver cirrhosis were at a 64.9 times greater risk (50.5 times in males and 100.4 times in females) and those with post-transfusion hepatitis were at a 9.4 times greater risk (8.9 times in males and 13.7 times in females) of developing liver cancer. Information on prognostic factors for 1,068 patients with decompensated liver cirrhosis was also collected in a questionnaire survey by the physicians in charge. Patients positive to hepatitis B surface antigen (HBs Ag) and those positive to HBe Ag had a significantly increased risk of subsequent liver cancer. The risk of developing liver cancer was positively associated with base-line levels of GPT and AFP and age and, inversely associated with total alcohol intake and female sex. In multivariate analyses, the associations with HBe Ag, AFP, sex and age remained statistically significant, whereas the associations with GPT, total alcohol intake and HBs Ag were of borderline significance.
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PMID:The risk and predictive factors for developing liver cancer among patients with decompensated liver cirrhosis. 127 45

Proliferation of a new population of epithelial cells with distinct structure, as well as cytokeratin and alpha-fetoprotein expression, was observed in nonneoplastic liver tissues from 14 cases (13 hepatitis B virus-positive) of human hepatocellular carcinoma. These cells were characterized by oval nuclei; scant, pale cytoplasm; small cell size; and cross-reaction with a monoclonal antibody against rat oval cells. These putative human oval cells were strongly positive for cytokeratin 19 and displayed considerable heterogeneity in alpha-fetoprotein and albumin expression. The oval cells were most prominent in actively regenerating nodules and in liver tissue surrounding the cancer. Oval cells and transitional types of cells appear to be the principal producers of alpha-fetoprotein in the regenerating liver. Cancer cells positive for cytokeratins 8, 18 and 19 were observed in half the hepatocellular carcinomas studied. The data suggest that a new cell population structurally similar to oval cells seen in early stages of chemical hepatocarcinogenesis in rats is consistently present in regenerating liver lesions associated with human hepatocellular carcinoma. Furthermore, it is possible that the proliferation of these oval-type cells may partly account for the elevation of serum alpha-fetoprotein frequently seen in precancerous stages of hepatitis B virus-associated human hepatocellular carcinoma.
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PMID:Occurrence of oval-type cells in hepatitis B virus-associated human hepatocarcinogenesis. 128 Feb 43

The effects of agents which are known to be differentiation inducers on a human hepatoma cell line PLC/PRF/5 were investigated. Dexamethasone (DEX), sodium butyrate (SB) or dimethylsulfoxide (DMSO) were examined. They all reduced cell proliferation but differ from each other in effect on the secretion of alphafetoprotein (AFP) and hepatitis B surface antigen (HBsAg), changes in morphology and RNA transcription. SB changed the cell from polygonal into a fibroblast-like type and decreased AFP secretion. DMSO decreased the cell size and changed AFP secretion in the same manner as SB. DEX changed the cell into a larger size, as well as increased AFP secretion. HBsAg secretion and also HB virus DNA transcription was enhanced by 3 agents. AFP and myc gene transcriptions were reduced by SB but DMSO reduced only AFP. Albumin gene transcription was enhanced by SB and DEX. These results indicate that the decrease of PLC/PRF/5 proliferation is induced through different mechanisms by these 3 agents.
Cancer Biochem Biophys 1992 Nov
PMID:Effect of dexamethasone, dimethylsulfoxide and sodium butyrate on a human hepatoma cell line PLC/PRF/5. 128 20

To evaluate the role of hepatitis C virus (HCV) in Chinese patients with hepatocellular carcinoma (HCC), the antibodies to HCV (anti-HCV) were detected by enzyme immunoassay in 41 (12.6%) of the 326 patients with HCC. However, none of 35 patients with metastatic carcinoma of the liver had detectable anti-HCV. The prevalence of anti-HCV was significantly higher in patients with hepatitis B surface antigen (HBsAg)-negative HCC than those with HBsAg-positive HCC (37.3% versus 4.1%, P less than 0.0001). However, the prevalence of anti-HCV was much higher in patients with HCC with negative results for HBsAg and antibody to hepatitis B core antigen (54.5%). The mean age of patients with HCC with positive results for anti-HCV was significantly greater than that of patients with HBsAg-positive HCC (65.1 versus 55.5 years, P less than 0.0001). Alpha-fetoprotein levels greater than 20 ng/ml were found in 70.7% of patients with HCC with positive results for anti-HCV and in 73.3% of patients with HBsAg-positive HCC. Of the Chinese patients with HCC, 74.5% had HBsAg-positive results and 96.6% had positive results for antibody to hepatitis core antigen. These data indicate that, although HCV may play an etiologic role in HCC, hepatitis B virus is still the most important causal agent among most Chinese patients with HCC.
Cancer 1992 Jan 15
PMID:The prevalence of anti-hepatitis C virus among Chinese patients with hepatocellular carcinoma. 130 28

Aflatoxin B1 has been suggested as a causative agent for a G to T mutation at codon 249 in the p53 gene in human hepatocellular carcinomas from southern Africa and Qidong in China. To test this hypothesis, nine tumors induced by aflatoxin B1 in nonhuman primates were analyzed for mutations in the p53 gene. These included four hepatocellular carcinomas, two cholangiocarcinomas, a spindle cell carcinoma of the bile duct, a hemangioendothelial sarcoma of the liver, and an osteogenic sarcoma of the tibia. None of the tumors showed changes at the third position of codon 249 by cleavage analysis of the HaeIII enzyme site at codon 249. A point mutation was identified in one hepatocellular carcinoma at the second position of codon 175 (G to T transversion) by sequencing analysis of the four conserved domains (II to V) in the p53 gene. These data suggest that mutations in the p53 gene are not necessary in aflatoxin B1 induced hepatocarcinogenesis in nonhuman primates. The occurrence of mutation in codon 249 of the p53 gene in selective samples of human hepatocellular cancers may indicate involvement of environmental carcinogens other than aflatoxin B1 or that hepatitis B virus-related hepatitis is a prerequisite for aflatoxin B1 induction of G to T transversion in codon 249.
Cancer Res 1992 Feb 15
PMID:Low frequency of p53 gene mutation in tumors induced by aflatoxin B1 in nonhuman primates. 131 Jun 37


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