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

The hepatitis C virus (HCV) is a small enveloped RNA virus belonging to the family flaviviridae and genus hepacivirus. The HCV RNA genome is 9,600 nucleotides in length and encodes a single polyprotein that is post-translationally cleaved into 10 polypeptides including t3 structural (C, E1, and E2) and multiple nonstructural proteins ([NS] NS2 to NS5). The NS proteins include enzymes necessary for protein processing (proteases) and viral replication (RNA polymerase). The virus replicates at a high rate in the liver and has marked sequence heterogeneity. There are 6 genotypes and more than 90 subtypes of HCV, the most common in the United States being 1a and 1b (approximately 75%), 2a and 2b (approximately 15%), and 3 (approximately 7%). Acute hepatitis C is marked by appearance of HCV RNA in serum within 1 to 2 weeks of exposure followed by serum alanine aminotransferase (ALT) elevations, and then symptoms and jaundice. Antibody to HCV (anti-HCV) tends to arise late. In acute resolving hepatitis, HCV RNA is cleared and serum ALT levels fall to normal. However, 55% to 85% of patients do not clear virus, but develop chronic hepatitis C. Chronic hepatitis C is often asymptomatic, but is usually associated with persistent or fluctuating elevations in ALT levels. The chronic sequelae of hepatitis C include progressive hepatic fibrosis, cirrhosis, and hepatocellular carcinoma. Extra-hepatic manifestations include sicca syndrome, cryoglobulinemia, glomerulonephritis, and porphyria cutanea tarda. Knowledge of the course and outcome of hepatitis C is important in developing approaches to management and therapy.
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PMID:Course and outcome of hepatitis C. 1240 73

Chronic hepatitis C virus (HCV) infection is common and often results in slowly progressive liver disease. Although acute hepatitis C is now uncommon, most patients with acute infection have developed chronic hepatitis, and, therefore, the pool of infected patients is large. We used a modification of a previously described natural history model for HCV infection to project the number of cases of HCV infection, cirrhosis, and liver failure over the next 40 years. The model estimated the prevalence of HCV infection in the United States was 3.07 x 10(6) in 1993 (compared with an adjusted National Health and Nutrition Evaluation Survey (NHANES) III estimate of 2.8 to 3.5 x 10(6)). A gradual decline in the prevalence of infection should occur by year 2040 because of aging and natural deaths among the infected pool. However, as the duration of infection increases in the surviving cohort, the proportion with cirrhosis will increase from 16% to 32% by 2020 in an untreated population. Complications of cirrhosis also will increase dramatically over the next 20 years: hepatic decompensation (up 106%), hepatocellular carcinoma (up 81%), and liver-related deaths (up 180%). Although current treatment regimens eradicate HCV in over 50% of cases, many more patients would need to be treated to significantly impact disease progression. Identification and treatment of every case of HCV infection (with or without cirrhosis) would reduce the number of cases of decompensated cirrhosis by almost half after 20 years. Despite the declining incidence of acute HCV infection, chronic hepatitis C is common. The prevalence of cirrhosis and the incidence of its complications will increase over the next 10 to 20 years, because the duration of infection increases among those with chronic hepatitis C. These data emphasize the need for greater access to transplantation by expansion of the donor pool, increasing use of split livers and living donors, and novel options such as xenotransplantation.
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PMID:Projecting future complications of chronic hepatitis C in the United States. 1268 82

Chronic hepatitis C virus (HCV) infection is a major health problem worldwide. The natural history of HCV infection is not fully understood. For years, there has been an overestimation of the rate of chronicity in acute HCV. Similar high rates of progression to cirrhosis in chronic HCV were reported. The source of confusion stems from the fact that most acute HCV infections are asymptomatic and never come to medical attention. The consequence of this is that most early studies of natural history reflect the more severe end of the spectrum of the disease. Recent studies reported 43-45% rate of chronicity as opposed to the old rates of 77-85%. Also, the rate of progression to cirrhosis and hepatocellular carcinoma was found to be much lower than previously reported. Multiple factors contribute to the chronicity and progression to cirrhosis, the most important being male gender, age, alcohol intake, and the degree of liver fibrosis on initial biopsy. At least 38% of patients with HCV will manifest symptoms of at least one extrahepatic complication. The most important extrahepatic manifestation is mixed cryoglobulinemia. Other extrahepatic manifestations and their response to antiviral therapy are discussed.
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PMID:The natural history of hepatitis C virus infection. 1289 3

Chronic Hepatitis C can progress to end-stage liver cirrhosis or hepatocellular carcinoma. Interferon (IFN) therapy is effective in clearing the hepatitis C virus and in improving liver histology, however, few patients maintain a sustained response (SR) after IFN withdrawal. Immediate retreatment with IFN is therefore considered to be both effective and necessary, especially for patients who do not respond to the initial course of IFN therapy. All 145 patients included in the present study underwent liver biopsy, followed by a first treatment course with various IFNs (alpha2a, alpha2b, alpha, OIF or beta). If hepatitis C virus (HCV) RNA was positive after the first treatment, the patient was assigned to one of 3 groups, depending on whether his or her alanine transaminase (ALT)level was normalized (incomplete response, IR), partially responsive(PR), or non-responsive (NR). After an observational interval of 6 to 76 months, a second IFN treatment was initiated with a higher dose or the same dose of the same IFN for the IR group, and with a different IFN for the PR and NR groups. At 6 months after retreatment with IFN, the overall efficacy of the retreatment was 29.7.% In the case of the IR group, who received the same IFN, the overall efficacy was 45.2%. In patients identified as non-SR after the first treatment, who received a different type of IFN for retreatment, the overall efficacy was 18.6%. Anti-IFN antibody was not detected in most of the breakthrough cases. For some IR patients, retreatment with the same IFN was effective. Anti-IFN antibody was mostly negative, indicating that the same IFN can be used in both the first treatment and retreatment to obtain an SR. Switching to a different IFN was effective for some PR and NR patients, suggesting that changing IFN for such cases is a good therapeutic choice.
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PMID:Efficacy of interferon retreatment on interferon-resistant patients with chronic hepatitis C. 1290 13

Chronic hepatitis C entails a life-long risk of developing cirrhosis and hepatocellular carcinoma and eradication of the hepatitis C virus (HCV) is the only realistic approach for lowering the risk of disease progression. Treatment is indicated for patients with high transaminases and histologic signs of chronic hepatitis: 6-12 month therapy with 3-6MU interferon alfa thrice weekly combined with 1-1.2 grams ribavirin yielded up to 30% sustained virological responses (SVR). SVR raised up to 50% with pegylated interferons combined with ribavirin. Favourable predictors of response to the former treatment are genotype 2 or 3, less than 2 million copies of HCV, no or portal fibrosis at biopsy, age less than 40 yr and female gender. The same was true for the latter treatment, however, with body weight less than 82 kg replacing female gender. Six month treatment is enough for treating genotype 2 or 3 patients whereas 12-month therapy is indicated for the more resistant patients with genotype 1 or 4.98% cure of community-acquired acute hepatitis C was achieved with early treatment with daily doses of 5MU interferon, compared to a calculated 30% virus clearance occurring in untreated patients. Cost-effective stopping rules based upon early clearance of serum HCV-RNA, are under investigation. A cut-off equal or more than 2 log decrease in serum HCV-RNA at week 12, has 97% negative predictive value and 60% positive predictive value. Treatment could be optimized also by retreatment with combination therapy of relapsers and non-responders to monotherapy, with SVR rates of 50% and 25%, respectively. Difficult-to-treat patients include patients who have high genotype 1 and 4 viremia or coinfection with HIV or hepatitis B virus as well as patients who carry an organ graft. Extended treatment of virological non responders with pegylated interferons might slow down progression of hepatic fibrosis and prevent hepatocellular carcinoma.
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PMID:Treatment of chronic hepatitis C. 1451 11

Chronic hepatitis C virus (HCV) is the most common bloodborne infection in the United States. An estimated 2.7 million Americans are infected, with the greatest prevalence of infection in African Americans at 3.2%. African Americans account for 22% of Americans with HCV. Recent studies have shown that African Americans are less likely to have cirrhosis than similarly infected non-Hispanic white patients and are more likely to have genotype 1 infection and to develop hepatocellular carcinoma. Several studies have shown that the response rates of African Americans to interferon and ribavirin are significantly lower than those for non-Hispanic whites. Despite the relatively low percentage of African-American patients in these early studies, similar preliminary results are being found in larger prospective studies with the newer treatment regimens of pegylated interferon and ribavirin. Differences in immunologic status, viral kinetics, and iron studies have also been found in HCV-infected African-American patients. Less is known about Mexican Americans and other minority groups because they are poorly represented in clinical trials. Efforts at increasing racial diversity in clinical trials are ongoing.
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PMID:Chronic hepatitis C in African Americans and other minority groups. 1472 Apr 56

Chronic hepatitis C virus (HCV) is a worldwide health problem. Approximately 4 million people in the United States are chronically infected with HCV. The incidence of infection peaked between 2 and 3 decades ago, and we are now beginning to see an increase in the complications of cirrhosis from HCV. This trend is expected to continue for another 2 to 3 decades. Survival is poor once complications of cirrhosis, such as liver failure or hepatocellular carcinoma, ensue, and liver transplantation is often the only option. Complications of chronic HCV are the most common indication for liver transplantation, accounting for more than 40% of transplants performed in the United States and Europe. HCV recurs in all patients and rapid development of hepatic fibrosis is very common. Several strategies have been proposed to reduce the risk of graft loss from recurrent HCV infection after transplantation, as the progression of the resulting liver disease is rapid. Although antiviral treatment is successful in some patients, it is extremely difficult to administer and requires dose reductions in the majority of cases. Retransplantation in the current era of the Model for End-Stage Liver Disease (MELD) system for prioritizing listing for transplant is associated with very low survival rates at a high cost. Furthermore, the system raises difficult ethical issues of utilization of limited resources and fairness to other transplant candidates.
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PMID:Chronic hepatitis C and liver transplantation. 1502 6

Chronic hepatitis C leads to cirrhosis in 20 to 30%. Hepatocellular carcinoma can develop in 1 to 5%. This natural course is modified by several factors including age, sex and alcohol. This last one is an important risk factor for fibrosis, cirrhosis and hepatocellular carcinoma. Data about high alcohol consumption show an increased risk whereas the risk associated with light to moderate consumption of alcohol remains unclear. Treatment of chronic hepatitis C with pegylated interferon and ribavirine allows a viral response in 50 to 80%. Factors decreasing this response rate are high viremia, genotype 1 and 4, sex and alcohol. Again, at which limit alcohol consumption is becoming deleterious is not well known. According to epidemiological studies alcohol consumption higher than 40 to 50 g/day should be avoided and a 6 months abstinence period before antiviral therapy should be recommended. Is this enough? More studies are needed to answer these questions.
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PMID:[Hepatitis C and alcohol, which is the limit?]. 1508 56

Chronic hepatitis C virus (HCV) infection is the most frequent cause of progressive liver disease and liver cancer in the West. The p53 tumor suppressor gene is known to play an important role in carcinogenesis of different tissues being involved in gene transcription, DNA synthesis and repair and somatic mutations of p53 are common in primary liver cancer. The p53 gene displays a common genetic Arg/Pro polymorphism at codon 72 with functional significance, that has been investigated as risk factor in several cancer models. We analyzed p53 codon 72 polymorphism in a group of 340 HCV-infected subjects at different stages of disease, including 84 hepatocellular carcinoma patients. No association between codon 72 genotypes and disease severity or liver cancer was observed.
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PMID:Codon 72 polymorphism of P53 gene does not affect the risk of cirrhosis and hepatocarcinoma in HCV-infected patients. 1510 48

Chronic hepatitis C is a leading cause of liver cirrhosis and hepatocellular carcinoma worldwide. Recent progress in the understanding of the molecular virology of hepatitis C has allowed the identification of novel antiviral targets. Moreover, in vitro and in vivo model systems have been developed that allow the systematic evaluation of new therapeutic strategies. Exciting results from proof-of-concept clinical studies have now been reported for a specific hepatitis C virus serine protease inhibitor. These and other novel antiviral strategies may complement existing therapeutic modalities in the future.
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PMID:Recent developments in target identification against hepatitis C virus. 1526 25


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