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

Exposure of female hepatitis B virus transgenic mice of lineage 50-4, which display liver injury secondary to overexpression of the gene for the large envelope polypeptide of hepatitis B virus, to the hepatocarcinogens aflatoxin and diethylnitrosamine produced more rapid and extensive evidence of nodule formation and oval cell proliferation, as well as the development of adenomas and primary hepatocellular carcinomas, than was seen in transgenic mice not exposed to carcinogens. Adult mice are known to be resistant to the effects of aflatoxin or diethylnitrosamine, and the livers of carcinogen-treated nontransgenic littermate controls were essentially normal. By the time of sacrifice (15 mo), 20 adenomas and 2 primary hepatocellular carcinomas were found in 26 transgenic mice given aflatoxin and 8 adenomas and 2 primary hepatocellular carcinomas were seen in the 8 mice exposed to diethylnitrosamine, but no adenomas or carcinomas were identified in the 10 transgenic mice not exposed to carcinogens. These results suggest that the chronic liver damage and repair caused by overexpression of the hepatitis B virus large envelope polypeptide in the hepatocytes of the transgenic lineage 50-4 act synergistically with chemical hepatocarcinogens to produce neoplasia of the liver.
 ...
PMID:Synergy between hepatitis B virus expression and chemical hepatocarcinogens in transgenic mice. 184 61

Although hepatocellular carcinoma is a relatively uncommon tumor in the United States, it is quite common in sub-Saharan Africa and the Far East, where most cases are associated with infection with the hepatitis B virus. We have studied 99 American patients with hepatocellular carcinoma for evidence of hepatitis B or hepatitis C viral infection and compared these findings to those in a group of matched controls with other cancers. The two groups differed in proportion, with hepatitis B surface antigen in serum being significantly higher in patients with hepatocellular carcinoma (7% vs. 0%, p = 0.009). Antibody to hepatitis C virus was also found more frequently in patients with hepatocellular carcinoma (13% vs. 2%, p = 0.002). The relative risk for hepatocellular carcinoma in hepatitis B surface antigen-positive patients was calculated to be 17.3 and for antibody to hepatitis C virus to be 7.3. The attributable fraction of cases related to the hepatitis B surface antigen carrier state was 6.7% and for patients infected with the hepatitis C virus was 11.4%. Approximately three quarters of cases of hepatocellular carcinoma did not have evidence of either hepatitis C or hepatitis B virus infection. These findings provide strong evidence that hepatitis C virus infection is associated with the development of hepatocellular carcinoma, and in the United States may even play a more important role than the hepatitis B virus.
 ...
PMID:The role of chronic viral hepatitis in hepatocellular carcinoma in the United States. 184 90

Adjuvants can be used with recombinant antigens to elicit cell-mediated immunity and antibodies of protective isotypes (IgG2a in the mouse and IgG1 in primates). Adjuvants should not produce reactions at injection sites, be pyrogenic or induce anterior uveitis or arthritis. Among 130 analogs of muramyl dipeptides tested, N-acetylmuramyl-L-threonyl-D-isoglutamine showed the greatest separation of potency as an adjuvant from potency in the production of side-effects. A stable emulsion of squalane and the Pluronic polymer L-121 provides a versatile vehicle for targeting of antigens to antigen-presenting cells. The combination of this emulsion with the threonyl analog of MDP is termed Syntex Adjuvant Formulation. This formulation increases the efficacy of influenza, hepatitis B virus, herpes simplex virus, lentivirus and tumor vaccines in experimental animals.
 ...
PMID:Immunological adjuvants: desirable properties and side-effects. 185 Jan 14

To determine the clonal evolution of hepatocellular carcinoma, the integrated hepatitis B virus DNA patterns of the main tumor, satellites and/or metastatic lesions were analyzed by Southern-blot hybridization in 28 hepatocellular carcinomas, including three HBsAg-seronegative cases. Unicentric or multicentric hepatocellular carcinoma was confirmed by histopathological criteria in 89% of the cases. Among 17 unicentric hepatocellular carcinomas, minor changes of the integration pattern--including partial loss or addition of the integration sites or both--were detected in the metastatic lesions in 29% of the cases. Furthermore, none of five cases with free-form hepatitis B virus DNA in the primary tumor had detectable free hepatitis B virus DNA in the metastatic lesions. These results suggest that the alteration of integrated hepatitis B virus DNA pattern during the course of tumor growth and metastasis may occur more often than previously perceived and that the switch-off of virus replication may be related to tumor metastatic potential. In eight cases with unilateral, multicentric hepatocellular carcinoma, two clones were detected in six cases, three were seen in another and four were seen in one. One case of note was a 9-yr-old boy with two histological types and two different integration patterns, one associated with vascular invasion and lung metastasis. Three patients with bilateral hepatocellular carcinoma were confirmed to have bicentric or tricentric hepatocellular carcinoma rather than intrahepatic dissemination and had survival rates similar to those in unicentric hepatocellular carcinoma. Three invasive HBsAg-seronegative hepatocellular carcinomas were found to have hepatitis B virus DNA integration and were of unicentric origin.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Clonality and clonal evolution of hepatocellular carcinoma with multiple nodules. 185 94

Interleukin-8 (IL-8) is a newly described leukocyte chemotactic and activating cytokine that belongs to the novel family of inflammatory cytokines whose genes locate on human chromosome 4, q12-21 region. The production of IL-8 is usually not constitutive and can be induced rapidly and abundantly in different cell types by a variety of stimuli such as lipopolysaccharide, interleukin-1, tumor necrosis factor-alpha as well as a tumor promotor phorbol myristate acetate. We report here that in addition to these stimuli the IL-8 gene can also be induced by the protein X of the hepatitis B virus (HBV-X) as evidenced by the enhanced IL-8 mRNA expression and IL-8 production observed in HBV-X-transfected cells. Furthermore, using several deletion mutants of the 5'-flanking regulatory region of the human IL-8 gene linked to the chloramphenicol acetyl transferase gene as a reporter, we have established here that both nuclear factor kB and CCAAT/enhancer-binding protein-like cis-elements located at -94 to -71 base pairs of IL-8 gene are essential and sufficient for the induction of the IL-8 gene by HBV-X. The same elements have been identified recently by us to be interleukin-1-, tumor necrosis factor-alpha-, and phorbol myristate acetate-responsive elements on the IL-8 gene. This suggests the existence of a common pathway for these inflammatory cytokines and HBV-X to activate the IL-8 gene. These observations might be relevant to the pathogenesis of inflammation in viral hepatitis.
 ...
PMID:Hepatitis B virus X protein transactivates human interleukin-8 gene through acting on nuclear factor kB and CCAAT/enhancer-binding protein-like cis-elements. 185 9

A teratoma was diagnosed in an 8-month-old pekin duck based on the presence of tissue derived from embryonic ectoderm, mesoderm, and endoderm in the neoplasm. The neoplasm was examined for the presence of duck hepatitis B virus, because the duck was congenitally infected with the virus, a member of the hepadnavirus family that is associated with hepatic neoplasms in hepadnavirus-infected mammals. Persistent infection occurred in the liver, but no evidence of viral infection was found in the neoplasm.
 ...
PMID:A teratoma in a duck infected congenitally with duck hepatitis B virus. 195 89

To assess the effects of the combination of persistent hepadnavirus infection and chemical carcinogen exposure, aflatoxin B1 (AFB) was administered p.o. for 60 days to congenitally duck hepatitis B virus (DHBV)-infected and virus-free Pekin ducks, starting at 3 days of age, during a 28-month study. Hepatic neoplasia occurred only in AFB-dosed ducks. Hepatocellular carcinomas or biliary carcinomas occurred in 4 of 8 DHBV-infected and 3 of 4 DHBV-free ducks, and hepatocellular adenomas developed in 2 DHBV-infected AFB-dosed ducks that survived 20 months or longer. Altered foci of hepatocytes similar to those observed in chemical carcinogen-dosed rodents, characterized by enlarged eosinophilic hepatocytes or vacuolated cytoplasm, occurred in AFB-dosed ducks. Cells in foci or hepatic neoplasms did not contain histochemically detectable gamma-glutamyltranspeptidase but were distinguished from uninvolved parenchyma by altered glycogen content. Immunohistochemical staining indicated that DHBV core antigen persisted in liver, spleen, pancreas, and, to a lesser extent, kidney of most congenitally infected ducks up to 28 months of age. Hepatic neoplasms contained only patches of hepatocytes were detectable viral antigen. Southern blot analysis of restriction endonuclease-digested neoplastic and normal liver DNA revealed high molecular weight forms of DHBV DNA consistent with integration of viral DNA into the genome of hepatic neoplasms from 3 of 4 DHBV-infected ducks but not nontumorous liver. These findings indicate that AFB is a potent hepatic carcinogen in ducks and that persistent congenital DHBV infection did not contribute significantly to the emergence of hepatic neoplasia in ducks under these conditions.
 ...
PMID:Hepatic neoplasms in aflatoxin B1-treated, congenital duck hepatitis B virus-infected, and virus-free pekin ducks. 197 46

The aim of the present study was to determine whether loss of DNA sequences at the chromosome arm 11p, where presumed tumor suppressor genes are located, might occur in hepatocellular carcinomas (HCCs) of hepatitis B virus (HBV) negative patients. Normal liver and HCC genotypes were compared at 6 loci on 11p with 7 polymorphic probes detecting 10 restriction length polymorphisms (RFLPs). Each of the 8 paired normal-tumor tissue samples was informative for at least three different loci on 11p13-pter. None of them showed loss of constitutional heterozygosity for those markers. The retainment of 11p alleles suggests that mechanisms other than loss of tumor suppressor genes on llp are involved in hepatocarcinogenesis of HBV negative patients.
 ...
PMID:No evidence for loss of alleles at 11p in HBV negative hepatocellular carcinomas. 198 Jun 6

Monoclonal antibodies have been raised against a cell line derived from a dimethylhydrazine-induced rat colon carcinoma. One of these antibodies (MAb E4) has previously been shown to react slightly with normal small intestine and colon, and not with other normal tissues as determined by immunohistochemistry. Using Western immunoblotting we confirmed this tumor specificity. Therefore, the Mr of approx. 66,000 glycosylated antigen (pE4) recognized by MAb E4 appeared to be a potential marker of colon carcinoma. Fifteen human tumor cell lines were tested by flow cytometry for the expression of pE4. This antigen was not detected on these cells. In the rat colon carcinoma cell, pE4 was exclusively found on the cell membrane. pE4 was purified to near homogeneity by immunoaffinity chromatography. The first 20 N-terminal amino acids were identified. Comparison with the NBRF data bank did not reveal a complete homology with known sequenced proteins but similarities were found with the mouse L3T4 precursor, the env polyprotein of human immunodeficiency virus type I, flagellin from Halobacterium halobium and the gp30 from hepatitis B surface antigen. Homology was always found in transmembranous or hydrophobic domains of these proteins. By indirect immunofluorescence analysis of adherent cells and size exclusion chromatography under native conditions, pE4 was found to interact with other molecules and perhaps to be involved in intercellular contact.
 ...
PMID:Characterization, isolation and amino terminal sequencing of a rat colon carcinoma-associated antigen. 201 Feb 33

The ribose moiety of 5-fluorouridine (FUR) was oxidized with periodate and the product was bound through a poly(L-lysine) bridge to monoclonal antibodies, denoted SF25MAb, reactive with a human colon carcinoma LS180. The antibody was linked via its polysaccharide (previously oxidized with periodate) to the poly(L-lysine)-drug conjugate. The linking of FUR-poly(L-lysine) to the antibody markedly increased the latter's binding to the tumor cells. A relatively lower increase was also observed with conjugates of nonrelated antibodies, such as anti-hepatitis B surface antigen and anti-epidermal growth factor receptor antibodies. The pharmacological activity of the specific conjugate FUR-poly(L-lysine) -SF25MAb was higher than that of the drug-substituted polymer alone. The poly(L-lysine) bridge caused toxic effects in vivo, even though substituted both by FUR and by antibody. Therefore, the additional unreacted lysyl residues were blocked by succinylation. Partial blocking of free amino groups on the conjugate rendered it nontoxic but decreased its cell-binding capacity, though to a level still higher than that of the original unmodified antibody. The pharmacological activity of the specific conjugate after blocking was also reduced and necessitated prolonged incubation periods or higher concentrations. Following periodate oxidation and reduction, FUR was as effective as the clinically preferred compound 5-fluoro-2'-deoxyuridine in vitro and in vivo, against the LS180 colon carcinoma. Experiments in nude mice, with LS180 tumor subcutaneous xenotransplants, showed that FUR-poly(L-lysine)-SF25MAb (blocked by succinylation) was not toxic and was effective in the retardation of tumor growth.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:A conjugate of 5-fluorouridine-poly(L-lysine) and an antibody reactive with human colon carcinoma. 209 21


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>