Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0019204 (hepatocellular carcinoma)
 71,386 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Infection with hepatitis B virus may develop into a chronic carrier state, which may result in chronic hepatitis, cirrhosis and hepatocellular carcinoma, but the exact mechanism of the development of hepatocellular carcinoma is still not known. The question is whether it is hepatitis B virus itself or the cellular changes due to persistent hepatitis B virus infection that cause malignant changes? The purpose of this article was to describe the natural history of hepatitis B virus infection together with epidemiological, serological, and molecular data that show a connection between chronic hepatitis B virus infection and the development of hepatocellular carcinoma.
 ...
PMID:[Hepatitis B--a viral oncogene?]. 1255 16

Chronic hepatitis B virus (HBV) infection can cause a broad spectrum diseases, including from asymptomatic HBV carriers or cryptic hepatitis, to acute hepatitis, chronic hepatitis, Liver cirrhosis and primary hepatocellular carcinoma. The variable pattern and clinical outcome of the infection were mainly determined by virological itself factors, host immunological factors and genetic factors as well as the experimental factors. Among the human genetic factors, major candidate or identified genes involved in the process of HBV infection fall into the following categories: (1) genes that mediate the processes of viral entry into hepatocytes, including genes involved in viral binding, fusion with cellular membrane and transportation in target cells; (2) genes that modulate or control the immune response to HBV infection; (3) genes that participate in the pathological alterations in liver tissue; (4) genes involved in the development of liver cirrhosis and hepatocellular carcinoma associated with chronic HBV infection, including genes related to mother-to-infant transmission of HBV infection; and (5) those that contribute to resistance to antiviral therapies. Most of the reports of human genes associated with HBV infection have currently focused on HLA associations. For example, some investigators reported the association of the HLA class II alleles such as DRB1*1302 or HLA-DR13 or DQA1*0501-DQB1*0301-DQB1*1102 haplotypes with acute and/or chronic hepatitis B virus infection, respectively. Several pro-inflammatory cytokines such as Th1 cytokines (including IL-2 and IFN-gamma) and TNF-alpha have been identified to participate the process of viral clearance and host immune response to HBV. In contrast, the Th2 cytokine IL-10 serves as a potent inhibitor of Th1 effector cells in HBV diseases. The MBP polymorphisms in its encoding region were found to be involved in chronic infection. Thus, reports from various laboratories have shown some inconsistencies with regard to the effects of host genetic factors on HBV clearance and persistence. Since genetic interactions are complex, it is unlikely that a single allelic variant is responsible for HBV resistance or susceptibility. However, the collective influence of several single nucleotide polymorphisms (SNPs) or haplotype (s) may underlie the natural combinational or synergistic protection against HBV. The future study including the multi-cohort collaboration will be needed to clarify these preliminary associations and identify other potential candidate genes. The ongoing study of the distributions and functions of the implicated allele polymorphisms will not only provide insight into the pathogenesis of HBV infection, but may also provide a novel rationale for new methods of diagnosis and therapeutic strategies.
 ...
PMID:Current status and prospects of studies on human genetic alleles associated with hepatitis B virus infection. 1267 1

The woodchuck hepatitis virus (WHV)/woodchuck system is studied as animal model of human hepatocellular carcinoma (HCC) induced by chronic hepatitis B virus infection. The aim of the present study was the evaluation of ultrasound (US) liver examination in woodchuck as a routine method to detect HCC nodules and to follow their growth. Sixteen woodchucks were included in the study. US liver examination was carried out in all animals using a 5 MHz convex scanner. Macroscopic and microscopic examinations were performed to evaluate the US findings. The lower limit of nodule detection by US examination was a diameter of 5 mm. Macroscopic and microscopic examinations confirmed US findings in 14 of 16 animals (86.6%). No false negative results were obtained. Increase of nodule size was faster in the early phase of tumour growth. Small nodules (16 +/- 5 mm) appeared as hypoechoic lesions with well-defined margins and homogeneous structure. Large nodules (42 +/- 19 mm) appeared as hyperechoic lesions with irregular margins, heterogeneous or of mixed pattern; microscopical examination showed different degrees of necrosis, inflammation and fibrosis inside these latter neoplasms. The hepatitis reaction was conspicuously more severe around HCC nodules. No fibrosis and/or cirrhosis were found in normal liver parenchyma surrounding tumour nodules. On the whole, US appears to be helpful in the diagnosis of woodchuck HCC even at an early stage. Serial US evaluation can be used to study the growth rate of tumour nodules during natural history or experimental HCC treatments in woodchuck.
 ...
PMID:Ultrasonography in the study of hepatocellular carcinoma in woodchucks chronically infected with WHV. 1286 86

Hepatitis B causes significant morbidity and mortality worldwide. More than 400 million persons, including 1.25 million Americans, have chronic hepatitis B. In the United States, chronic hepatitis B virus infection is responsible for about 5,000 annual deaths from cirrhosis and hepatocellular carcinoma. Hepatitis B virus is found in body fluids and secretions; in developed countries, the virus is most commonly transmitted sexually or via intravenous drug use. Occupational exposure and perinatal transmission do occur but are rare in the United States. Effective vaccines for hepatitis B virus have been available since 1982; infant and childhood vaccination programs introduced in the 1990s have resulted in a marked decrease in new infections. Risk factors for progression to chronic infection include age at the time of infection and impaired immunity. From 15 to 30 percent of patients with acute hepatitis B infection progress to chronic infection. Medical therapies for chronic hepatitis B include interferon alfa-2b, lamivudine, and the nucleotide analog adefovir dipivoxil.
 ...
PMID:Hepatitis B. 1472 20

We made a prospective study on the development of hepatocellular carcinoma (HCC) in patients with liver cirrhosis with hepatitis B virus infection from April, 1973 to December, 1977. Seven out of 30 patients (23%) with hepatitis B surface antigen (HBsAg)-positive cirrhosis developed HCC. On the other hand, only 5.9% of the patients with HBsAg-negative liver cirrhosis developed HCC. These patients were classified into three groups according to their anti-HB core (anti-HBc) titers. When the anti-HBc titer, expressed as a dilution of serum, was 2(10) or more (Group I), 20-24% of the liver cirrhosis patients developed HCC either with or without a detectable amount of HBs Ag present in the sera. When the anti-HBc titer was 2(9) or less (Group II), only 0-5.7% developed HCC. There was no significant difference between this and the anti-HBc and HBsAg-negative group (Group III), which was 4.4%. In five individual cases from group I, HBsAg was detected in serum, and in biopsies of liver cells, before HCC could be detected by angiography and/or rising levels of alphafetoprotein (AFP). In all of these cases, the anti-HBc titer was higher than 2(10) throughout the observation period, even before the development of HCC. These findings indicate that active virus proliferation in chronic hepatitis B virus infection precedes the development of HCC as indicated by a higher anti-HBc titer. Therefore we have prepared these studies to show the pathogenic role of hepatitis B virus in the development of hepatocellular carcinoma.
 ...
PMID:A prospective study on the development of hepatocellular carcinoma from liver cirrhosis with persistent hepatitis B virus infection. 1476 3

We prospectively followed 426 children with chronic hepatitis B virus infection. During 6250 person-years, 2 boys developed hepatocellular carcinoma, with an incidence of 32 per 100,000 person-years. Both had e antigen seroconversion in early childhood and cirrhosis. Early e antigen seroconversion and/or cirrhosis may be risk factors for hepatocellular carcinoma.
 ...
PMID:The development of hepatocellular carcinoma among prospectively followed children with chronic hepatitis B virus infection. 1500 56

The treatment of the patient with chronic hepatitis B virus infection (HBV) must be carried out with the knowledge that the percentage of patients infected with the B virus that develop chronic hepatitis remains between 5-10%. Of these, 10-30% will present chronic infection with active viral replication, necroinflammatory hepatic lesion, evolution to hepatic cirrhosis and the risk of developing hepatocarcinoma. For this reason, the aim of treatment is to achieve negativisation of the HBeAg, seroconversion to anti-HBe and a reduction of viral replication to undetectable values (estimated by level of DNA-HBV), for protracted periods of time. When a sustained loss of HBeAg and a reduction of viral replication are obtained, a biochemical, clinical and histological remission is achieved. Up until now the therapeutic alternatives in chronic infection by the B virus have been immunomodulation with Interferon alpha and the blocking of viral replication with lamivudine or adefovir dipivoxil. A difference must be drawn between the biochemical response, defined as a fall in the transaminases to normal values, and the virological response, which refers to a fall in the levels of DNA-HBV below 10(5) copies/ml. Finally, the complete response is defined as the virological and biochemical response with negativisation of the HBsAg. If a sustained response is obtained for several months, a histological response can be predicted with reduction in the intensity of the hepatic lesion and an absence or stabilisation in the process of fibrosis. The sustained response should last for no less than 6 to 12 months following the end of treatment.
 ...
PMID:[Treatment of chronic hepatitis B virus infection]. 1538 41

Patients who are chronically infected with the hepatitis B virus are at an increased risk of developing cirrhosis, hepatic decompensation and hepatocellular carcinoma. Therapeutic intervention offers the only means of interrupting this progression. Currently there are three licensed agents for the treatment of chronic hepatitis B virus infection. These are interferon-alpha, an immunomodulator, and two synthetic nucleos(t)ide analogs, namely lamivudine (Epivir, GlaxoSmithKline) and adefovir dipivoxil (Hepsera, Gilead Sciences). This review aims to summarize current experience with these drugs in the treatment and management of patients with chronic hepatitis B virus infection, their efficacy, and current problems of drug resistance. An outline of future treatment perspectives is also included.
 ...
PMID:Current therapies for chronic hepatitis B virus infection. 1548 37

High rates of hepatocellular carcinoma (HCC) in The Gambia, West Africa, are primarily due to a high prevalence of chronic hepatitis B virus infection and heavy aflatoxin exposure via groundnut consumption. We investigated genetic polymorphisms in carcinogen-metabolizing (GSTM1, GSTT1, HYL1*2) and DNA repair (XRCC1) enzymes in a hospital-based case-control study. Incident HCC cases (n = 216) were compared with frequency-matched controls (n = 408) with no clinically apparent liver disease. Although the prevalence of variant genotypes was generally low, in multivariable analysis (adjusting for demographic factors, hepatitis B virus, hepatitis C virus, and TP53 status), the GSTM1-null genotype [odds ratio (OR), 2.45; 95% confidence interval (95% CI), 1.21-4.95] and the heterozygote XRCC1-399 AG genotype (OR, 3.18; 95% CI, 1.35-7.51) were significantly associated with HCC. A weak association of the HYL1*2 polymorphism with HCC was observed but did not reach statistical significance. GSTT1 was not associated with HCC. The risk for HCC with null GSTM1 was most prominent among those with the highest groundnut consumption (OR, 4.67; 95% CI, 1.45-15.1) and was not evident among those with less than the mean groundnut intake (OR, 0.64; 95% CI, 0.20-2.02). Among participants who had all three suspected aflatoxin-related high-risk genotypes [GSTM1 null, HLY1*2 (HY/HH), and XRCC1 (AG/GG)], a significant 15-fold increased risk of HCC was observed albeit with imprecise estimates (OR, 14.7; 95% CI, 1.27-169). Our findings suggest that genetic modulation of carcinogen metabolism and DNA repair can alter susceptibility to HCC and that these effects may be modified by environmental factors.
 ...
PMID:Hepatocellular carcinoma and polymorphisms in carcinogen-metabolizing and DNA repair enzymes in a population with aflatoxin exposure and hepatitis B virus endemicity. 1573 60

Hepatocellular carcinoma (HCC) is a common human malignancy that is often associated with risk factors such as aflatoxin-B1 (AFB1) exposure and Hepatitis-B virus infection in developing countries. There is a strong correlation between these risk factors and mutation of the tumor-suppressor gene p53 at codon 249. In vitro experiments have also shown that treatment of human liver cells with AFB1 results in p53 mutations. A tumor-promoting role for mutant p53 was demonstrated using transgenic mice models, in which HCC development was accelerated upon AFB1-exposure. However, wild-type mice in which AFB1 alone was used to induce liver cancers have failed to recapitulate p53 mutations, raising the possibility that mouse DNA context may not be appropriate for the generation of AFB1-induced p53 mutations. We have now tested this hypothesis using the Hupki mice (human p53 knock-in) in which the mouse DNA-binding domain has been replaced by the homologous human p53 segment. Mice were followed for 80 weeks after AFB1 injection for survival and HCC formation. Hupki mice were found to be more susceptible to AFB1 than wild-type mice. Moreover, only 19% of wild-type mice developed HCCs compared to 44% in Hupki mice. However, none of the liver tumors and normal tissues from Hupki mice contained any mutations in the DNA-binding domain of p53. These findings suggest that the human DNA context of the p53 gene alone may not be the sole determinant of AFB1-induced mutagenesis. Furthermore, humanized p53 appears not to be as effective as murine p53 in the mouse cellular environment in preventing malignant transformation.
 ...
PMID:Aflatoxin-B exposure does not lead to p53 mutations but results in enhanced liver cancer of Hupki (human p53 knock-in) mice. 1655 86


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