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)

Chronic infection with hepatitis B virus (HBV) has been reported in two-thirds of cases of hepatocellular carcinoma (HCC) in Greece from 1973 to 1995, while chronic hepatitis C virus (HCV) infection in 10% of them. We studied the roles of HBV and HCV in HCC in Greece between 1996 and 2000 compared with the past, and possible differences in clinical and laboratory characteristics of HBV- and HCV-related HCC. Complete clinical and laboratory data from 306 patients with HCC, diagnosed from January 1996 to December 2000, were analyzed. Chronic HBV and HCV infection were detected in 52.3 and 21.6% of the patients, respectively. The ratio of HBV- to HCV-related HCC was 2.42. Compared with the data prior to 1996, there was a 101.8% increase in the relative frequency of HCV (P < 0.0001) and an 11.8% decrease in that of HBV (P = 0.033), with a -56.3% change in the ratio of HBV- to HCV-related HCC cases. Statistically significant differences in the male/female ratio, median age and frequency of multifocal lesions were found in HBV- vs HCV-related HCC. Although HBV still represents the major aetiological factor of HCC in Greece, its role has significantly decreased in the last 5 years, while a more significant increase has occurred in HCV-related HCC. The two aetiological types of HCC differ in Greece in demographic, epidemiological and other features.
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PMID:Changing relative roles of hepatitis B and C viruses in the aetiology of hepatocellular carcinoma in Greece. Epidemiological and clinical observations. 1463 79

Hepatocellular carcinoma (HCC) is one of the 10 most common malignant tumors worldwide. Chronic infection with hepatitis B or C virus is closely related to hepatocarcinogenesis. The outcome of current therapies for HCC is not satisfactory. Prevention is the best way to control HCC. Among the various strategies of HCC prevention, immunization against hepatitis B virus infection is the most effective. Universal hepatitis B immunization has proved to be effective in reducing the incidence of HCC to 1/4-1/3 of that in children born before the hepatitis B vaccination era in Taiwan. The problems we face in achieving global control of hepatitis-related HCC include: (1) no effective vaccine for the prevention of hepatitis C and its related HCC; (2) no immunization program for hepatitis B in areas with inadequate resources; (3) poor compliance to the immunization program as a result of ignorance, anxiety, or poverty; and (4) vaccine failure. Integration of the hepatitis B vaccination program into the expanded program of immunization for all infants throughout the world will be most urgent and important for HCC control. The reduction of the incidence of HCC will be seen in adults 30-40 years of age after the launch of the universal hepatitis B vaccination program. This concept of cancer vaccine can be applied to other infectious agents and their related cancers.
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PMID:Decreasing incidence of hepatocellular carcinoma among children following universal hepatitis B immunization. 1470 90

Chronic infection with hepatitis B or C virus (HBV or HCV) is the most clearly established risk factor for hepato-cellular carcinoma (HCC). One type of HCC (non-B, non-C HCC) also appears to develop in patients negative for both HBV and HCV. Using a supervised learning method, we investigated gene expression in 11 non-B, non-C HCCs with high-density oligonucleotide microarrays, and compared the patterns of gene expression with those of HBV-infected HCCs (B-type HCCs) and HCV-infected HCCs (C-type HCCs) in the previous dataset. Our gene selection identified 112 and 64 genes that were differentially expressed in non-B, non-C HCC in comparison with B- and C-type HCCs, respectively. In both gene selections, we found that the false discovery rate, the percentage of genes identified by chance, was less than 5%. Additionally, in combination with the previous data, our present data revealed a set of genes specific to each type of B- and C-type HCCs and non-B, non-C HCC. Among these, an interferon-induced gene, IFI27, was differentially expressed among all three types of HCCs, and this result was confirmed by RT-PCR. Thus, our present study provides a framework to characterize the molecular features in the three subtypes of HCC with different viral origin.
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PMID:Molecular signature in three types of hepatocellular carcinoma with different viral origin by oligonucleotide microarray. 1476 41

Chronic infection with hepatitis B virus (HBV) has potentially devastating consequences and is very difficult to treat. Therapy with recombinant interferons (IFN), especially IFN-alpha, may be effective. The blood IFN-alpha levels that are needed to maintain therapeutic IFN-alpha levels in the liver, however, often cause severe side effects. Gene delivery to the liver may provide a solution. Using a long-term expression construct could provide the desired levels of IFN locally without the need to maintain potentially problematic blood levels. Recombinant, Tag-deleted SV40-derived vectors transduce hepatocytes efficiently and provide permanent transgene expression. We designed an expression construct that was effective against HBV and whose activity was limited to HBV-infected cells. To do this, we exploited the ability of HBV X protein to activate NF-kappaB and, via NF-kappaB, to activate promoter activity of HIV long terminal repeat (LTR) in hepatocytes. Using HIVLTR as a conditional promoter upstream of human and murine IFN-alpha and IFN-gamma cDNAs, rSV40 vectors were used to test the responsiveness of IFN to HBV and the ability of these IFNs to inhibit HBV transcripts and protein production and to activate IFN signaling in neighboring untransduced cells. We found that in hepatocyte cell lines and in primary hepatocytes, HBV activated the promoter activity of the HIVLTR via NF-kappaB. When whole HBV genome was delivered to cells by transfection to simulate HBV infection, IFN expression was activated, IFNs were produced and secreted, and they protected cells from HBV. Levels of IFN proteins that were secreted in this context were comparable to targeted blood levels needed to control chronic hepatitis viral infection. Further, IFNs that were elicited and secreted in this manner were able to activate IFN-induced signaling pathways in neighboring, untransduced cells and so were likely to provide protection even to cells that the rSV40 vector did not transduce. Gene delivery using such rSV40 vectors expressing IFNs conditionally in response to HBV may be an attractive therapeutic option for the treatment of chronic hepatitis B.
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PMID:Conditional expression of IFN-alpha and IFN-gamma activated by HBV as genetic therapy for hepatitis B. 1476 47

Chronic infection with hepatitis B virus (HBV) is an important clinical problem due to its worldwide distribution and potential of adverse sequelae including hepatocellular carcinoma (HCC). Hepatitis B e antigen (HBeAg) is a biomarker of active viral proliferation in hepatocytes and infectivity. The prevalence of HBeAg among subjects chronically infected with HBV decreases with the increase in age. Case series studies have found a lowest seroprevalence of HBeAg in HCC patients compared with patients affected with chronic hepatitis B and liver cirrhosis. Case-control studies have shown a significantly higher seroprevalence of HBeAg in HCC cases than matched controls. A recent long-term follow-up study has shown a significantly elevated HCC risk for seropositives of both hepatitis B surface antigen (HBsAg) and HBeAg compared with seropositives of HBsAg only and seronegatives. The biological gradient remained in further stratification analyses by serum level of alanine transaminase and status of liver cirrhosis detected by ultrasonography. The cumulative HCC risk from age 30 to 70 years has been estimated to be 87% for those who were persistently seropositive on HBsAg and HBeAg, 12% for those with persistent seropositivity of HBsAg only, and 1% for those who were seronegative on HBsAg and HBeAg.
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PMID:Seropositivity of hepatitis B e antigen and hepatocellular carcinoma. 1518 77

Chronic infection with either hepatitis B (HBV) or hepatitis C virus (HCV) is frequently present in patients seropositive for human immunodeficiency virus (HIV) because of shared routes of transmission. With the advent of highly active antiretroviral therapy (HAART) regimens capable of controlling HIV replication and dramatically prolonging the survival of HIV-infected patients, the impact of co-morbid infections such as HBV and HCV has come into focus. Several studies have monitored HBV or HCV viral loads following initiation of HAART, with disparate results. The effects of HAART on hepatitis B and C plasma viral loads (n = 9 and 32, respectively) and on liver enzyme levels were studied in a large cohort of prospectively studied subjects with advanced stage HIV disease. Comparing the mean pre- and post-HAART levels, there was an estimated increase of (a) 1.40 log(10) from 4.83 to 6.24 log(10) for HBV plasma viral load (P = 0.07), (b) 0.74 log(10) from 6.38 to 7.12 log(10) for HCV plasma viral load (P = 0.001), and (c) 19.4 U/L from 37.4 to 56.8 U/L for serum alanine aminotransferase (P < 0.001). While the number of subjects co-infected with HIV and HBV was limited, these data collected in a population of advanced stage HIV-infected patients raises questions regarding the interactions of these viruses with each other and the host immune system and has implications regarding the order in which antiviral therapies are initiated.
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PMID:Hepatitis B and C viral load changes following initiation of highly active antiretroviral therapy (HAART) in patients with advanced HIV infection. 1530 41

Hepatocellular carcinoma (HCC) is the most important primary hepatic cancer, being a common cancer type worldwide. Many aetiological factors have been related with HCC development, such as cirrhosis, hepatitis viruses and alcohol. Chronic infection with hepatitis B (HBV) and C viruses (HCV) often results in cirrhosis and enhances the probability of developing HCC. The underlying mechanisms that lead to malignant transformation of infected cells, however, remain unclear. HBV is a DNA virus that integrates into the host genome, and this integration is believed, in part, to be carcinogenic. Besides, the virus encodes a 17 kDa protein, HBx, which is known to be a causative agent in the formation of HCC. On the contrary, HCV is a RNA virus that does not integrate into the host genome but likely induces HCC through host protein interactions or via the inflammatory response to the virus. Products encoded in the HCV genome interfere with and disturb intracellular signal transduction. Some HCV proteins, such as the core protein, NS3 and NS5A, have seen to have a regulatory effect on cellular promoters, to interact with a number of cellular proteins, and to be involved in programmed-cell death modulation under certain conditions. The identification of these proteins functions in HCC development and the subsequent development of strategies to inhibit protein-protein interactions may be the first step towards reducing the chronicity and/or of the carcinogenicity of these two viruses.
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PMID:Hepatocellular carcinoma: role of hepatitis B and hepatitis C viruses proteins in hepatocarcinogenesis. 1535 43

Chronic infection with hepatitis B and its sequelae remains a major global health concern. Despite recommendations and implementation of vaccination programs, the health and economic burdens are still significant. People in endemic areas and immigrants from these areas need to be adequately screened and treated. HBeAg-negative chronic hepatitis is increasingly recognized with additional challenges in management. Programs implementing primary prophylaxis strategies such as vaccination of high-risk adult and adolescent groups should continue.
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PMID:Hepatitis B: epidemiology and natural history. 1548 39

Chronic infection with the hepatitis B virus (HBV) is a major risk factor for development of hepatocellular carcinoma (HCC). The pathogenesis of cancer in HBV infection has been extensively analyzed, and multiple factors appear to play a role. A major factor is chronic inflammation and the effects of cytokines in the development of fibrosis and liver cell proliferation. Also important is the role of integration of HBV DNA into host cellular DNA, which, in some situations, acts to disrupt or promote expression of cellular genes that are important in cell growth and differentiation. In addition, expression of HBV proteins may have a direct effect on cellular functions, and some of these gene products can favor malignant transformation. Several HBV genes have been found in infected tissues more frequently than others, including truncated pre-S2/S, hepatitis B X gene, and a novel spliced transcript of HBV, referred to as the hepatitis B spliced protein. The proteins expressed from these integrated genes have been shown to have intracellular activities that may account for their association with HCC, including effects on cellular growth and apoptosis. Finally, some patients with HCC have no detectable hepatitis B surface antigen in serum but do have low levels of HBV DNA in serum and integrated molecules of HBV DNA in tissue. Occult HBV infection may account for a proportion of cases of HCC that occur in patients without serologic markers for hepatitis B and C and may be a cofactor in HCC in patients with chronic hepatitis C who have coexistent occult HBV infection.
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PMID:Pathogenesis of hepatitis B virus-related hepatocellular carcinoma: old and new paradigms. 1550 4

Chronic infection with the hepatitis B virus remains a serious and life-threatening disease for approximately 5% of the world's population, despite the availability of effective vaccines. Although prognoses can be improved by chemotherapy, treatment options are limited and none has been consistently successful. Interferon-alpha, the longest established therapy, has limited efficacy, is slow-acting and frequently causes adverse effects. Newer drugs comprise of mainly nucleoside and nucleotide analogs. The two that are currently approved, lamivudine and adefovir dipivoxil, are well tolerated; both produce rapid and dramatic responses, but their effects may not be sustainable in the long-term due to the emergence of resistant virus. Development of resistance to lamivudine is approximately ten-times more frequent than development of resistance to adefovir dipivoxil (approximately 60 and 6%, respectively) during the first 3 years of therapy. Entecavir, a carbocyclic deoxyguanosine analog that is active against both lamivudine- and adefovir dipivoxil-resistant HBV, is in the vanguard of new antihepatitis B virus drugs that have progressed to Phase III clinical trials. It is the most potent antihepatitis B virus agent discovered to date.
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PMID:Entecavir for the treatment of chronic hepatitis B. 1556 30


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