Chronic active hepatitis(CAH) is acknowledged as an imperative risk factor for the development of liver injury and hepatocellular carcinoma.The histological end points of CAH are chronic inflammation,fibrosis and cirr...Chronic active hepatitis(CAH) is acknowledged as an imperative risk factor for the development of liver injury and hepatocellular carcinoma.The histological end points of CAH are chronic inflammation,fibrosis and cirrhosis which are coupled with increased DNA synthesis in cirrhotic vs healthy normal livers.The potential mechanism involved in CAH includes a combination of processes leading to liver cell necrosis,inflammation and cytokine production and liver scaring(fibrosis).The severity of liver damage is regulated by Hepatitis B virus genotypes and viral components.The viral and cellular factors that contribute to liver injury are discussed in this article.Liver injury caused by the viral infection affects many cellular processes such as cell signaling,apoptosis,transcription,DNA repair which in turn induce radical effects on cell survival,growth,transformation and maintenance.The consequence of such perturbations is resulted in the alteration of bile secretion,gluconeogenesis,glycolysis,detoxification and metabolism of carbohydrates,proteins,fat and balance of nutrients.The identification and elucidation of the molecular pathways perturbed by the viral proteins are important in order to design effective strategy to minimize and/or restore the hepatocytes injury.展开更多
Hepatocellular carcinoma(HCC)is one of the leading causes of death induced by cancer in the modern world and majority of the cases are related to chronic hepatitis B virus(HBV)infection.HBV-encoded X protein(HBx)is kn...Hepatocellular carcinoma(HCC)is one of the leading causes of death induced by cancer in the modern world and majority of the cases are related to chronic hepatitis B virus(HBV)infection.HBV-encoded X protein(HBx)is known to play a pivotal role in the pathogenesis of viral induced HCC.HBx is a multifunctional protein of17 kDa which modulates several cellular processes by direct or indirect interaction with a repertoire of host factors resulting in HCC.HBX might interfere with several cellular processes such as oxidative stress,DNA repair,signal transduction,transcription,protein degradation,cell cycle progression and apoptosis.A number of reports have indicated that HBx is one of the most common viral ORFs that is often integrated into the host genome and its sequence variants play a crucial role in HCC.By mutational or deletion analysis it was shown that carboxy terminal of HBx has a likely role in protein-protein interactions,transcriptional transactivation,DNA repair,cell,signaling and pathogenesis of HCC.The accumulated evidence thus far suggests that it is difficult to understand the mechanistic nature of HBx associated HCC,and HBx mediated transcriptional transactivation and signaling pathways may be a major determinant.This article addresses the role of HBx in the development of HCC with particular emphasis on HBx mutants and their putative targets.展开更多
Hepatocellular carcinoma(HCC) is etiologically linked with hepatitis B virus(HBV) and is the leading cause of death amongst 80% of HBV patients. Among HBV affected patients, genetic factors are also involved in modify...Hepatocellular carcinoma(HCC) is etiologically linked with hepatitis B virus(HBV) and is the leading cause of death amongst 80% of HBV patients. Among HBV affected patients, genetic factors are also involved in modifying the risk factors of HCC. However, the genetic factors that regulate progression to HCC still remain to be determined. In this review, we discuss several single nucleotide polymorphisms(SNPs) which were reportedly associated with increased or reduced risk of HCC occurrence in patients with chronic HBV infection such as cyclooxygenase(COX)-2 expression specifically at COX-2-1195G/A in Chinese, Turkish and Egyptian populations, tumor necrosis factor α and the three most commonly studied SNPs: PAT-/+, Lys939Gln(A33512C, rs2228001) and Ala499Val(C21151T, rs2228000). In genome-wide association studies, strong associations have also been found at loci 1p36.22, 11q22.3, 6p21(rs1419881, rs3997872, rs7453920 and rs7768538), 8p12(rs2275959 and rs37821974) and 22q11.21. The genes implicated in these studies include HLA-DQB2, HLA-DQA1, TCF19, HLA-C, UBE2L3, LTL, FDX1, MICA, UBE4 B and PG. The SNPs found to be associated with the above-mentioned genes still require validation in association studies in order to be considered good prognostic candidates for HCC. Screening of these polymorphisms is very beneficial in clinical experiments to stratify the higher or lower risk for HCC and may help in designing effective and efficient HCC surveillance programs for chronic HBV-infected patients if further genetic vulnerabilities are detected.展开更多
文摘Chronic active hepatitis(CAH) is acknowledged as an imperative risk factor for the development of liver injury and hepatocellular carcinoma.The histological end points of CAH are chronic inflammation,fibrosis and cirrhosis which are coupled with increased DNA synthesis in cirrhotic vs healthy normal livers.The potential mechanism involved in CAH includes a combination of processes leading to liver cell necrosis,inflammation and cytokine production and liver scaring(fibrosis).The severity of liver damage is regulated by Hepatitis B virus genotypes and viral components.The viral and cellular factors that contribute to liver injury are discussed in this article.Liver injury caused by the viral infection affects many cellular processes such as cell signaling,apoptosis,transcription,DNA repair which in turn induce radical effects on cell survival,growth,transformation and maintenance.The consequence of such perturbations is resulted in the alteration of bile secretion,gluconeogenesis,glycolysis,detoxification and metabolism of carbohydrates,proteins,fat and balance of nutrients.The identification and elucidation of the molecular pathways perturbed by the viral proteins are important in order to design effective strategy to minimize and/or restore the hepatocytes injury.
基金King Fahd Medical Research Center (KFMRC) and Center of Genomic Medicine (CEGMR) for financial support
文摘Hepatocellular carcinoma(HCC)is one of the leading causes of death induced by cancer in the modern world and majority of the cases are related to chronic hepatitis B virus(HBV)infection.HBV-encoded X protein(HBx)is known to play a pivotal role in the pathogenesis of viral induced HCC.HBx is a multifunctional protein of17 kDa which modulates several cellular processes by direct or indirect interaction with a repertoire of host factors resulting in HCC.HBX might interfere with several cellular processes such as oxidative stress,DNA repair,signal transduction,transcription,protein degradation,cell cycle progression and apoptosis.A number of reports have indicated that HBx is one of the most common viral ORFs that is often integrated into the host genome and its sequence variants play a crucial role in HCC.By mutational or deletion analysis it was shown that carboxy terminal of HBx has a likely role in protein-protein interactions,transcriptional transactivation,DNA repair,cell,signaling and pathogenesis of HCC.The accumulated evidence thus far suggests that it is difficult to understand the mechanistic nature of HBx associated HCC,and HBx mediated transcriptional transactivation and signaling pathways may be a major determinant.This article addresses the role of HBx in the development of HCC with particular emphasis on HBx mutants and their putative targets.
基金Supported by The STACK-Large grant 162-34 to Ishtiaq QadriIQ Foundation
文摘Hepatocellular carcinoma(HCC) is etiologically linked with hepatitis B virus(HBV) and is the leading cause of death amongst 80% of HBV patients. Among HBV affected patients, genetic factors are also involved in modifying the risk factors of HCC. However, the genetic factors that regulate progression to HCC still remain to be determined. In this review, we discuss several single nucleotide polymorphisms(SNPs) which were reportedly associated with increased or reduced risk of HCC occurrence in patients with chronic HBV infection such as cyclooxygenase(COX)-2 expression specifically at COX-2-1195G/A in Chinese, Turkish and Egyptian populations, tumor necrosis factor α and the three most commonly studied SNPs: PAT-/+, Lys939Gln(A33512C, rs2228001) and Ala499Val(C21151T, rs2228000). In genome-wide association studies, strong associations have also been found at loci 1p36.22, 11q22.3, 6p21(rs1419881, rs3997872, rs7453920 and rs7768538), 8p12(rs2275959 and rs37821974) and 22q11.21. The genes implicated in these studies include HLA-DQB2, HLA-DQA1, TCF19, HLA-C, UBE2L3, LTL, FDX1, MICA, UBE4 B and PG. The SNPs found to be associated with the above-mentioned genes still require validation in association studies in order to be considered good prognostic candidates for HCC. Screening of these polymorphisms is very beneficial in clinical experiments to stratify the higher or lower risk for HCC and may help in designing effective and efficient HCC surveillance programs for chronic HBV-infected patients if further genetic vulnerabilities are detected.