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)

Chronic hepatitis B virus (HBV) infection is an important cause of cirrhosis and hepatocellular carcinoma. Current treatments are limited and may be ineffective. Nucleic acid-mediated targeting of viral mRNA is an attractive and specific approach for viral infection and lentiviral vectors provide a means to express antisense sequences or ribozymes stably in target cells permitting continuous production within that cell and its progeny. To demonstrate long-term gene expression by lentiviral vectors in hepatocytes and to introduce lentiviral vectors expressing anti-HBV genes to assess their effect against HBV, lentiviral vectors expressing a reporter gene were assessed for longevity of gene expression in hepatocytes in vitro. Hammerhead ribozymes and antisense sequences targeting the HBV encapsidation signal (epsilon), X or surface antigen on mRNAs were cloned into lentiviral vectors and used to transduce HBV expressing hepatocytes where the effect on HBV mRNA level was assessed using ribonuclease protection. Gene expression in hepatocytes from integrated vectors continued for over 4 months without selection. Antisense RNA targeting HBs mRNA reduced this transcript, whilst antisense RNA to HBX mRNA was ineffective. Sense RNAs corresponding to epsilon and HBX mRNA also reduced HBV mRNA levels. Ribozymes targeting HBs and HBX mRNA effectively reduced HBV mRNA levels compared with inactive constructs indicating their effect to be enzymatic rather than antisense. Lentiviral vectors can produce long-term gene expression in hepatocytes and thus permit prolonged expression of antiviral genes targeting the HBV encapsidation signal, surface and X mRNAs as treatments for chronic HBV infection.
 ...
PMID:Inhibition of hepatitis B virus by lentiviral vector delivered antisense RNA and hammerhead ribozymes. 1598 4

Chronic hepatitis B infection (HBV) is a major health problem worldwide. The prognosis is grave for patients with HBV-related decompensated liver cirrhosis (LC). We evaluated the effectiveness and the determinants of early mortality of lamivudine treatment in patients with HBV-related decompensated LC. Thirty patients with HBV-related decompensated LC and active viral replication were treated with lamivudine 100 mg daily for a median duration of 9 months. Among these patients, five patients died within 3 months. Two patients were lost to follow-up at week 8 and 9. One patient was treated for <6 months. Twenty-two patients were treated over 6 months. Univariate analysis revealed that the total bilirubin (P = 0.008), prothrombin time (P = 0.004), Child-Turcotte-Pugh score (P = 0.005), the model of efd-stage liver disease score (P = 0.004) and stage III hepatic encephalopathy (P = 0.001) were predictive factors of early mortality. Multivariate analysis revealed that the independent factor associated with early mortality was stage III encephalopathy. Among 22 patients, liver function improved markedly after lamivudine therapy. Of the nine hepatitis B e antigen (HBeAg)-positive patients, three had HBeAg seroconversion. Two patients had YMDD mutant and virological breakthrough at 41 and 46 weeks. One of the two had hepatocellular carcinoma and died of hepatic failure at week 125; the other received adefovir and is doing well. Lamivudine appeared to have benefits in viral suppression and significant improvement in liver function in patients with HBV-related decompensated LC. As noted in prior studies, poor baseline liver function is associated with a poor prognosis in Asian patients with decompensated HBV cirrhosis treated with lamivudine.
 ...
PMID:Determinants of early mortality and benefits of lamivudine therapy in patients with hepatitis B virus-related decompensated liver cirrhosis. 1598 9

Chronic hepatitis B virus (HBV) infection by definition is persistence of hepatitis B surface antigen (HBsAg) in the serum for > or =6 months. The risk of developing chronic HBV infection ranges from 90% in neonates to <5% in immunocompetent adults. HBV acquired by perinatal infection has a prolonged immune-tolerant phase, characterized by the presence of hepatitis Be antigen (HBeAg), high HBV-DNA and normal alanine aminotransferase (ALT) levels. Efficient and multi-specific helper and cytotoxic T-cell response is essential for controlling HBV infection. Chronic HBV infection is characterized by a state of HBV-specific T-cell hyporesponsiveness. The goal of therapy in chronic HBV infection is to eliminate or significantly suppress HBV replication and prevent the progression of liver disease to cirrhosis with the potential development of liver failure or hepatocellular carcinoma (HCC). In adults, drugs currently licensed for treatment of HBV infection: are interferon-alpha (IFN-alpha), lamivudine (LMV) and adefovir dipivoxil (ADV), the first two are also licensed to use in children. IFN-alpha has the advantage of having a more durable response, fixed duration of treatment and lack of resistant mutants. The disadvantages of IFN-alpha include need for thrice-weekly injections, higher cost and more side-effects compared with the nucleoside analogues. Nucleoside analogues can be given orally and used in decompensated cirrhosis and transplant recipients. ADV and newer drugs like tenefovir can successfully treat mutants produced after prolonged LMV therapy. Current protocols exclude children with immunotolerant HBV. Periodic screening with liver ultrasound scan and alpha-fetoprotein (AFP) in all children with chronic HBV infection is recommended. The severe shortage of cadaveric donor organs has led to the use of marginal (including anti-HBc-positive) cadaveric donor livers in selected transplant candidates with high medical urgency; 5-10% of all liver transplants are because of HBV. Using hepatitis B immunoglobulin and nucleoside analogues has made the outcome following liver transplantation for hepatitis B, comparable with, if not slightly better, than that in patients with other diagnoses. Future treatments should be based on the restoration of HBV-specific T-cell responses to levels similar to that seen in subjects controlling HBV.
 ...
PMID:Hepatitis B in children: complexities in management. 1617 31

Chronic hepatitis B virus (HBV) infection is a major health problem that is responsible for < or = 1 million deaths and 500,000 cases of hepatocellular carcinoma worldwide each year. Drugs that are currently approved by the FDA for the treatment of chronic HBV consist of two groups: the immunomodulators, such as conventional IFN-alpha and pegylated IFN-alpha2a; and nucleoside/nucleotide analogues, such as lamivudine, adefovir dipivoxil and entecavir. However, due to the limitations of these agents, newer agents with improved efficacy are currently being developed. One nucleoside/nucleotide analogue that is drawing a wide range of interest is clevudine, which is an analogue of the unnatural beta-L configuration. In the woodchuck hepatitis virus (WHV), clevudine 10 mg/kg has proven to be effective in suppressing viral replication with < or = 9 log10 decreases in WHV. At this dose, a significant reduction of intrahepatic WHV RNA and covalently closed circular WHV DNA levels can also be observed. Treatment with clevudine 10 mg/kg can confer additional antiviral benefit in the form of a more sustained reduction in WHV replication, serum woodchuck hepatitis surface antigen and intrahepatic woodchuck hepatitis core antigen expression following the withdrawal of clevudine. In humans, clevudine 10, 50, 100 or 200 mg/day for 28 days can reduce the median HBV DNA by -2.5, -2.7, -3 and -2.6 log10, respectively. More importantly, this suppression of antiviral activity is maintained at 12 and 24 weeks post treatment. Based on the early results of clevudine, more large-scale human studies with clevudine monotherapy or combination therapy is eagerly awaited.
 ...
PMID:Clevudine for the treatment of chronic hepatitis B virus infection. 1618 70

Chronic hepatitis B virus (HBV) infection constitutes a major public health problem particularly in developing countries in East Asia, South-East Asia, the Pacific Basin and Africa. In Malaysia, a developing nation in the South East Asian region, the chronic HBV carrier rate varies between < 1% to about 10% depending on the ethnic group studied. The highest frequency is seen among the Chinese, followed by the Malays and lastly the Indians, with a male preponderance of between 2 : 1 and 3 : 1. Exposure to the virus among the adult population is estimated to be about 15%, 26% and 36% among the Indians, Malays and Chinese respectively. Serological study of adult chronic HBV carriers showed a frequency of HBe antigenemia of about 35%, with a significant decreasing trend with age. HBV DNA status generally correlated with the HBe status. An atypical profile of anti-HBe associated with serum HBV DNA is found in some carriers; in most instances, this is related to seroconversion from HBe antigenemia to anti-HBe. Chronic complications of HBV infection include the development of hepatocellular carcinoma (HCC), the occurrence of which closely parallel that of HBsAg carrier rate. In Malaysia, HCC is the third most common malignant neoplasm and among the 10 leading causes of death. About 80% of our HCC cases are HBV associated. All 3 ethnic groups are afflicted, the highest frequency being among the Chinese. Males show a disproportionate risk with an odds ratio of 3.93 (p < 0.0001).
 ...
PMID:Chronic hepatitis B infection in Malaysians. 1632 67

Chronic hepatitis B virus (HBV) infection affects over 350 million people worldwide and over 1 million die annually of HBV-related chronic liver disease. Although many individuals eventually achieve a state of nonreplicative infection, the prolonged immunologic response to infection leads to the development of cirrhosis, liver failure, or hepatocellular carcinoma (HCC) in up to 40% of patients. In endemic areas, where carrier rates are >5%, most individuals are infected perinatally, by vertical transmission, or in early childhood. In the United States, where prevalence is low except in particular areas and populations (e.g., Alaskan natives, immigrants from highly endemic areas), transmission is generally horizontal, percutaneous, or via sexual contact in adulthood. A variety of host (age at infection, gender, immune status); viral (viral load, genotype, mutation); and external (concurrent viral infections, alcohol consumption, chemotherapy) factors influence disease progression. Several variables (age at infection, gender, ethnicity, immune status) also influence the risk of chronic infection. Perinatal transmission, the most common mode of infection worldwide, can be reduced by appropriate prophylaxis (vaccination of the infant at birth together with hepatitis B immune globulin); anti-viral therapy in late pregnancy may also be beneficial. Five drugs are now FDA-approved for the treatment of HBV (interferon, lamivudine, adefovir, entecavir, and peginterferon alfa-2a), and suppressive anti-viral therapy improves the natural history of HBV. Patients with decompensated cirrhosis or HCC are highly likely to die unless they successfully undergo liver transplantation. While novel anti-viral drugs have improved the management of cirrhosis, strategies to prevent and treat HCC remain inadequate.
 ...
PMID:Introduction to chronic hepatitis B infection. 1644 46

Chronic hepatitis B infection presents a number of challenges to clinicians. There are additional considerations when defining management strategies for individuals with advanced liver disease, or coinfection, or those at high risk of developing hepatocellular carcinoma (HCC). Treatment of decompensated cirrhosis is particularly important. Evidence suggests that suppression of viral replication through nucleos(t)ide analog therapy leads to longer time to transplantation, improved liver function, and improved survival times. The use of interferon in patients with decompensated hepatitis B is associated with serious complications and is currently contraindicated for these patients by the AASLD Practice Guidelines. Hepatitis B coinfection is often associated with more extensive disease. In patients with HBV/HCV coinfection, one disease is usually dominant and consequently should be the focus of therapy. HIV/HBV coinfection increases the risk of progressive liver disease. Therapeutic agents active against both viruses should be utilized at the correct dose to limit the development of resistance. Agents specific for HBV, e.g., entecavir, enable hepatitis to be treated while avoiding the risk of HIV resistance developing. Dual infection with HBV and HDV is particularly challenging. Nucleos(t)ide analogs are ineffective in treating HDV infection, and there is limited data concerning the efficacy of interferon in this setting. The association between chronic hepatitis B infection and hepatocellular carcinoma (HCC) is well established. In patients at high risk of HCC, screening regimes may be effective. Furthermore, there is an increasing body of evidence indicating that effective suppression of viral replication may be associated with a reduced risk of HCC.
 ...
PMID:Optimizing management strategies in special patient populations. 1644 49

Chronic hepatitis B is usually a benign disease in Caucasian children; however, the long-term prognosis remains unsettled. This report describes the results of a 29-year longitudinal study including 99 white children with chronic hepatitis B, mainly acquired horizontally: 91 were hepatitis B e antigen (HBeAg) positive (4 had cirrhosis), and 8 were HBeAg negative at presentation. Of the 91 HBeAg-positive children, 89 underwent HBeAg seroconversion after a mean period of 5.2 +/- 4.0 years and were included in the study. Of the 85 children without cirrhosis, one had HBeAg-negative hepatitis and the other 84 became inactive carriers. During a mean follow-up of 14.5 +/- 6.1 years after HBeAg seroclearance, 4 carriers experienced reactivation, and 3 of them had HBeAg-negative hepatitis at the last follow-up. Of the 8 initially HBeAg-negative children, 2 had HBeAg-negative hepatitis, and 6 were inactive carriers. Of the 4 children with cirrhosis, 2 had hepatocellular carcinoma (HCC) and remained alive and 2 lost the histological features of cirrhosis in adulthood. Two patients with HBeAg-negative hepatitis and 1 with cirrhosis had experienced drug abuse. At the end of follow-up, 15 of the 89 initially HBeAg-positive patients and 2 of 8 initially HBeAg-negative children had cleared hepatitis B surface antigen. In conclusion, the overall prognosis for chronic hepatitis B in horizontally infected Caucasian children is favorable; however, some patients progress to HCC and HBeAg-negative hepatitis. Long-term monitoring is important, as is counseling on cofactors of liver damage, such as alcohol and drug abuse.
 ...
PMID:Chronic hepatitis B in children after e antigen seroclearance: final report of a 29-year longitudinal study. 1649 23

One-third of HIV-infected individuals worldwide suffer from chronic hepatitis C virus (HCV) infection, but chronic hepatitis C affects more than 75% of HIV-positive subjects infected parenterally, such as haemophiliacs and intravenous drug users. Chronic hepatitis B virus (HBV) infection, on the other hand, occurs in 10% of HIV-infected persons, coinfection being more prevalent in Southeast Asia. There are two main reasons for considering HCV and HBV therapy as a priority in HIV-coinfected patients: first, the more rapid liver disease progression seen in this population, leading to end-stage liver disease complications, including hepatocellular carcinoma, at younger ages; and second, the higher risk of developing hepatotoxicity following the initiation of antiretroviral therapy in subjects with underlying chronic hepatitis than in HIV-monoinfected individuals. As highly active antiretroviral therapy (HAART) has dramatically improved the prognosis of those with HIV disease, the consequences of associated illnesses such as hepatitis B and C, which are currently among the leading causes of hospital admission and death in the HIV-infected population, have become more relevant. Therefore, the adequate management of viral hepatitis should now be considered a priority in HIV-coinfected patients. Several guidelines have recently been released in response to this demand. In this article, we discuss the most critical issues highlighted in these documents.
 ...
PMID:Management of chronic hepatitis B and C in HIV-coinfected patients. 1655 38

Chronic hepatitis B is the most common cause of hepatocellular carcinoma (HCC) in Asia. Integration of hepatitis B virus (HBV) genome is likely an early event of carcinogenesis. The integrated HBV genome may activate neighboring cellular genes directly to offer a selective growth advantage to the liver cells. Production of hepatitis B X protein can act as a transactivator on various cellular genes for tumor development. Hepatic inflammation and cirrhosis also favors the process of carcinogenesis. Various viral factors associated with hepatocellular carcinoma development include HBV genotype, basal core promoter mutations, and high viral load. Polymorphisms at the androgen receptor-regulating genes and cytokine genes are possible host factors associated with HCC. This review article summarizes the pathogenesis of HBV-related carcinogenesis and the viral and host factors that may increase the risk of HCC development.
 ...
PMID:Hepatocellular carcinoma and hepatitis B virus. 1667 93


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