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1.
J Biol Chem ; 292(50): 20379-20393, 2017 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-29046350

RESUMO

Promyelocytic leukemia nuclear bodies (PML-NB) are sub-nuclear organelles that are the hub of numerous proteins. DNA/RNA viruses often hijack the cellular factors resident in PML-NBs to promote their proliferation in host cells. Hepatitis B virus (HBV), belonging to Hepadnaviridae family, remains undetected in early infection as it does not induce the innate immune response and is known to be the cause of several hepatic diseases leading to cirrhosis and hepatocellular carcinoma. The association of PML-NB proteins and HBV is being addressed in a number of recent studies. Here, we report that the PML-NB protein Speckled 110 kDa (Sp110) is SUMO1-modified and undergoes a deSUMOylation-driven release from the PML-NB in the presence of HBV. Intriguingly, Sp110 knockdown significantly reduced viral DNA load in the culture supernatant by activation of the type I interferon-response pathway. Furthermore, we found that Sp110 differentially regulates several direct target genes of hepatitis B virus protein X (HBx), a viral co-factor. Subsequently, we identified Sp110 as a novel interactor of HBx and found this association to be essential for the exit of Sp110 from the PML-NB during HBV infection and HBx recruitment on the promoter of these genes. HBx, in turn, modulates the recruitment of its associated transcription cofactors p300/HDAC1 to these co-regulated genes, thereby altering the host gene expression program in favor of viral persistence. Thus, we report a mechanism by which HBV can evade host immune response by hijacking the PML-NB protein Sp110, and therefore, we propose it to be a novel target for antiviral therapy.


Assuntos
Vírus da Hepatite B/metabolismo , Hepatite B Crônica/metabolismo , Hepatócitos/metabolismo , Corpos de Inclusão Viral/metabolismo , Antígenos de Histocompatibilidade Menor/metabolismo , Proteínas Nucleares/metabolismo , Sumoilação , Transativadores/fisiologia , Apoptose , Biomarcadores/sangue , Biomarcadores/metabolismo , DNA Viral/metabolismo , Regulação Bacteriana da Expressão Gênica , Células Hep G2 , Vírus da Hepatite B/crescimento & desenvolvimento , Vírus da Hepatite B/imunologia , Vírus da Hepatite B/isolamento & purificação , Hepatite B Crônica/imunologia , Hepatite B Crônica/patologia , Hepatite B Crônica/virologia , Hepatócitos/imunologia , Hepatócitos/patologia , Hepatócitos/virologia , Interações Hospedeiro-Patógeno , Humanos , Imunidade Inata , Corpos de Inclusão Viral/patologia , Corpos de Inclusão Viral/virologia , Antígenos de Histocompatibilidade Menor/sangue , Antígenos de Histocompatibilidade Menor/genética , Proteínas Nucleares/antagonistas & inibidores , Proteínas Nucleares/sangue , Proteínas Nucleares/genética , Regiões Promotoras Genéticas , Transporte Proteico , Interferência de RNA , Carga Viral , Proteínas Virais/genética , Proteínas Virais/metabolismo , Proteínas Virais Reguladoras e Acessórias , Fenômenos Fisiológicos Virais , Replicação Viral
2.
BMC Infect Dis ; 17(1): 76, 2017 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-28088184

RESUMO

BACKGROUND: Toll like receptors (TLRs) play an important role in innate immunity and various studies suggest that TLRs play a crucial role in pathogenesis of hepatitis B virus (HBV) infection. The present study aims in looking into the status of crucial host and viral gene expression on inciting TLR7. METHODS: The transcription of TLR7 pathway signaling molecules and HBV DNA viral load were quantified by Real Time-PCR after stimulation of TLR7 with its imiquimod based ligand, R837. Cell cycle analysis was performed using flow-cytometry. Expression of TLR7 and chief cell cycle regulator governing G1/S transition, p53 was also seen in liver biopsysss samples of CHB patients. HBV induced alteration in histone modifications in HepG2 cells and its restoration on TLR7 activation was determined using western blot. RESULTS: The TLR7 expression remains downregulated in HepG2.2.15 cells and in liver biopsy samples from CHB patients. Interestingly HBV DNA viral load showed an inverse relationship with the TLR7 expression in the biopsy samples. We also evaluated the anti-viral activity of R837, an agonist of TLR7. It was observed that there was a suppression of HBV replication and viral protein production upon TLR7 stimulation. R837 triggers the anti-viral action probably through the Jun N-terminal Kinase (JNK) pathway. We also observed a downregulation of histone H3K9Me3 repression mark upon R837 treatment in HBV replicating HepG2.2.15 cells, mimicking that of un-infected HepG2 cells. Additionally, the G1/S cell cycle arrest introduced by HBV in HepG2.2.15 cells was released upon ligand treatment. CONCLUSION: The study thus holds a close insight into the changes in hepatocyte micro-environment on TLR7 stimulation in HBV infection.


Assuntos
Antivirais/farmacologia , Vírus da Hepatite B/efeitos dos fármacos , Hepatócitos/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Quinolinas/farmacologia , Receptor 7 Toll-Like/agonistas , Carga Viral/efeitos dos fármacos , Replicação Viral/efeitos dos fármacos , Western Blotting , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular , Células Cultivadas , DNA Viral/efeitos dos fármacos , Regulação para Baixo , Células Hep G2 , Vírus da Hepatite B/genética , Hepatócitos/virologia , Histonas/efeitos dos fármacos , Humanos , Imunidade Inata , Lamivudina/farmacologia , Sistema de Sinalização das MAP Quinases/genética , Microscopia Confocal , NF-kappa B/efeitos dos fármacos , NF-kappa B/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Transdução de Sinais
3.
Indian J Med Res ; 143(5): 636-42, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27488008

RESUMO

BACKGROUND & OBJECTIVES: Hepatitis B virus (HBV) and HIV co-infection has variable prevalence worldwide. In comparison to HBV mono-infection, the course of chronic HBV infection is accelerated in HIV/HBV co-infected patients. the present study was carried out to analyse the baseline characteristics (clinical, biochemical, serological and virological) of treatment naïve HIV/HBV co-infected and HIV mono-infected patients. METHODS: Between July 2011 and January 2013, a total number of 1331 HIV-seropositive treatment naïve individuals, enrolled in the ART Centre of Calcutta School of Tropical Medicine, Kolkata, India, were screened for hepatitis B surface antigen (HBsAg). A total of 1253 HIV mono-infected and 78 HIV/HBV co-infected patients were characterized. The co-infected patients were evaluated for HBeAg and anti-HBe antibody by ELISA. HIV RNA was quantified for all co-infected patients. HBV DNA was detected and quantified by real time-PCR amplification followed by HBV genotype determination. RESULTS: HIV/HBV co-infected patients had proportionately more advanced HIV disease (WHO clinical stage 3 and 4) than HIV mono-infected individuals (37.1 vs. 19.9%). The co-infected patients had significantly higher serum bilirubin, alanine aminotransferase (ALT), alkaline phosphatase and ALT/platelet ratio index (APRI). CD4 count was non-significantly lower in co-infected patients. Majority (61.5%) were HBeAg positive with higher HIV RNA (P<0.05), HBV DNA (p<0.001) and APRI (p<0.05) compared to those who were HBeAg negative. HBV/D was the predominant genotype (73.2%) and D2 (43.7%) was the commonest subgenotype. INTERPRETATION & CONCLUSIONS: HIV/HBV co-infected patients had significantly higher serum bilirubin, ALT, alkaline phosphatase and lower platelet count. HBeAg positive co-infected patients had higher HIV RNA and HBV DNA compared to HBeAg negative co-infected patients. Prior to initiation of antiretroviral treatment (ART) all patients should be screened for HBsAg to initiate appropriate ART regimen.


Assuntos
Coinfecção/fisiopatologia , Infecções por HIV/fisiopatologia , HIV/patogenicidade , Vírus da Hepatite B/patogenicidade , Hepatite B/fisiopatologia , Adolescente , Adulto , Idoso , Feminino , Infecções por HIV/sangue , Infecções por HIV/virologia , Hepatite B/sangue , Hepatite B/virologia , Antígenos de Superfície da Hepatite B/sangue , Vírus da Hepatite B/isolamento & purificação , Humanos , Masculino , Pessoa de Meia-Idade
4.
Int J Mol Sci ; 16(8): 17746-62, 2015 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-26247932

RESUMO

Hepatitis B virus (HBV) attacks the liver and can cause both acute as well as chronic liver diseases which might lead to liver cirrhosis and hepatocellular carcinoma. Regardless of the availability of a vaccine and numerous treatment options, HBV is a major cause of morbidity and mortality across the world. Recently,microRNAs (miRNAs) have emerged as important modulators of gene function. Studies on the role of miRNA in the regulation of hepatitis B virus gene expression have been the focus of modern antiviral research. miRNAs can regulate viral replication and pathogenesis in a number of different ways, which includefacilitation, direct or indirect inhibition, activation of immune response, epigenetic modulation, etc. Nevertheless, these mechanisms can appropriately be used with a diagnosticand/or therapeutic approach. The present review is an attempt to classify specific miRNAs that are reported to be associated with various aspects of hepatitis B biology, in order to precisely present the participation of individual miRNAs in multiple aspects relating to HBV.


Assuntos
Carcinoma Hepatocelular/etiologia , Hepatite B/metabolismo , Cirrose Hepática/etiologia , Neoplasias Hepáticas/etiologia , MicroRNAs/genética , Animais , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/virologia , Hepatite B/complicações , Hepatite B/genética , Hepatite B/virologia , Interações Hospedeiro-Patógeno/genética , Humanos , Cirrose Hepática/genética , Cirrose Hepática/metabolismo , Cirrose Hepática/virologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/virologia
5.
BMC Cancer ; 14: 721, 2014 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-25260533

RESUMO

BACKGROUND: Hepatitis B Virus (HBV) X protein (HBx) is known to be involved in the initiation and progression of hepatocellular carcinoma (HCC) through modulation of host gene response. Alterations in miRNA expressions are frequently noted in HCC. This study is aimed to examine the role of HBx protein in the modulation of oncogenic miRNA-21, miRNA-222 and tumor suppressor miRNA-145 in malignant hepatocytes. METHODS: Expressions of miRNA-21, miRNA-222 and miRNA-145 were measured in HepG2 cells transfected with HBx-plasmid (genotype D) and with full length HBV genome (genotype D) and also in stably HBV producing HepG2.2.15 cells using real time PCR. Their target mRNAs and proteins - PTEN, p27 and MAP3K - were analyzed by real time PCR and western blot respectively. miRNA expressions were measured after HBx/D mRNA specific siRNA treatment. The expressions of these miRNAs were analyzed in liver cirrhosis and HCC patients also. RESULTS: The study revealed a down-regulation of miRNA-21 and miRNA-222 expressions in HBx transfected HepG2 cells, pUC-HBV 1.3 plasmid transfected HepG2 cells as well as in HepG2.2.15 cells. Down regulation of miRNA-21 and miRNA-222 expression was observed in patient serum samples. Down regulation of miRNA-145 expression was observed in HepG2 cells transiently transfected with HBx and pUC-HBV1.3 plasmid as well as in patient samples but the expression of miRNA-145 was increased in HepG2.2.15 cells. Target mRNA and protein expressions were modulated in HepG2 cells and in HepG2.2.15 cell line consistent with the modulation of miRNA expressions. CONCLUSION: Thus, HBx protein differentially modulated the expression of miRNAs. The study throws light into possible way by which HBx protein acts through microRNA and thereby regulates host functioning. It might suggest new therapeutic strategies against hepatic cancer.


Assuntos
Hepatoblastoma/virologia , Cirrose Hepática/virologia , Neoplasias Hepáticas/virologia , MicroRNAs/genética , Transativadores/metabolismo , Adulto , Feminino , Células Hep G2 , Vírus da Hepatite B/fisiologia , Hepatoblastoma/genética , Humanos , Cirrose Hepática/genética , Neoplasias Hepáticas/genética , Masculino , MicroRNAs/metabolismo , Pessoa de Meia-Idade , Transdução de Sinais , Proteínas Virais Reguladoras e Acessórias
6.
J Med Virol ; 85(8): 1340-7, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23765773

RESUMO

In a previous study from eastern India, the prevalence of HBV/C has been increasing among the blood donors. In order to analyze whether there has been any shift in HBV genotype distributions in recent years, the HBV genotypes prevalent during the periods 2000-2002 (Group-I; n=176) and 2007-2009 (Group-II; n=203) were compared, with special attention to changes in the proportion of HBV/C. The rate of prevalence of the three HBV genotypes (A, C, and D; percent prevalence 19.9/21.6/58.5 in Group-I vs. 31.0/28.6/40.4 in Group-II) underwent significant changes with increases in HBV/A and HBV/C among the HBV carriers (0.002). Among the asymptomatic carriers, the prevalence of these two genotypes (P=0.021 for HBV/A and P=0.005 for HBV/C) was significantly high. A notable increase was also observed among the chronic liver disease cases. HBV/A increased significantly among the older age Groups (≥ 51 years), whereas the increase of HBV/C was significant among the younger age Groups (≤ 20 years). With the increase of HBV/A and HBV/C, the rates of basal core promoter double mutation (1762T/1764A) also increased considerably. Binary logistic regression analysis revealed that both HBV/A and 1762T/1764A mutations are predictors of chronic liver disease state over asymptomatic carrier state. Thus, this study highlights the possible influence of HBV genotype shift on the changing scenario of HBV epidemiology and disease in the population.


Assuntos
Portador Sadio/epidemiologia , Portador Sadio/virologia , Vírus da Hepatite B/classificação , Vírus da Hepatite B/genética , Hepatite B/epidemiologia , Hepatite B/virologia , Adulto , Feminino , Genótipo , Vírus da Hepatite B/isolamento & purificação , Humanos , Índia/epidemiologia , Masculino , Pessoa de Meia-Idade , Epidemiologia Molecular , Dados de Sequência Molecular , Prevalência , Análise de Sequência de DNA , Adulto Jovem
7.
Virol J ; 10: 56, 2013 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-23409946

RESUMO

BACKGROUND: Antiviral therapy using nucleos(t)ide analogues (NAs) is an effective control measure of chronic hepatitis B virus (HBV) infection; however they need long term treatment. Presence of drug-resistance mutations may get in the way of the efficacy of antiviral therapy. Our study was aimed at defining the prevalence of HBV drug-resistance in HBVrt region in a population of 147 HBsAg positive patients. FINDINGS: HBV/D has shown multiple types of HBVrt mutations both among treatment naïve (65.0%, 13 of 20 HBV/D) and treated patients (56.2%, 9 of 16 HBV/D). In additional, several mutations, with a suggested role in drug resistance, were detected among the treatment naïve as well as the treated patients. The mutations reported to be involved in reduction of drug effectiveness, was common among non-responders to therapy as well as among the naïve patients. Notably, classical antiviral resistance mutations (rtL80I/V-rtI169T-rtV173L-rtL180M-rtA181T/V/S-rtT184A/S/G/C-rtA194T-rtS202C /G/I -rtM204V/I-rtN236T-rtM250V) were not detected. CONCLUSION: The prevalence of putative NAr mutations among non responders to therapy suggests that they might have role in reduced efficacy of currently available antivirals and requires further investigations.


Assuntos
Farmacorresistência Viral , Vírus da Hepatite B/genética , Hepatite B Crônica/virologia , Mutação de Sentido Incorreto , Adulto , Antivirais/uso terapêutico , DNA Viral/química , DNA Viral/genética , Feminino , Vírus da Hepatite B/isolamento & purificação , Hepatite B Crônica/tratamento farmacológico , Humanos , Índia , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Polimorfismo Genético , Prevalência , Estudos Retrospectivos , Análise de Sequência de DNA , Resultado do Tratamento , Adulto Jovem
8.
ScientificWorldJournal ; 2013: 212704, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24302857

RESUMO

A previous study from West Bengal documented very high rate of occult HBV infection (OBI) among the HBsAg negative blood donors. This study was aimed to characterize the OBI strains circulating among the blood donors and to estimate the risk associated with the prevailing viral variants/mutants. Blood samples from 2195 voluntary blood donors were included in the study. HBsAg, HBeAg, anti-HBc, and anti-HBs statuses of the samples were done by ELISA based detection. PCR amplification and sequencing were done to determine HBV genotypes, basal core promoter (BCP), and precore (Pre-C) mutations. Among the study samples, 268 were anti-HBc positive/HBsAg negative, among which 65 (24.25%) were HBV DNA positive. Phylogenetic analysis revealed the presence of HBV/D (87.23%), HBV/A (8.51%), and HBV/C (4.26%) (P < 0.0001). HBV/D3 (65.85%) was the significantly prevalent subgenotype over HBV/D2 (26.83%) and HBV/D1 (7.31%) (P = 0.0003). Considerable prevalence of differential BCP (1752C, 1753C, 1762T/1764A, 1753C+1762T/1764A, 1773C, and 1814C) and reverse transcriptase (rt) gene (rtI91L, rtL93P, rtS106C, rtR110G, rtN118T, rtS119T, rtY126H, rtG127W/R, rtC136R, and rtY158H) mutations was identified. Association of specific HBV subgenotypes with OBI was interesting and needs further study. Clinically relevant mutations were prevalent among the OBI strains which are of serious concern.


Assuntos
Doadores de Sangue , Vírus da Hepatite B/genética , Hepatite B/virologia , Adulto , Hepatite B/imunologia , Anticorpos Anti-Hepatite B/sangue , Antígenos de Superfície da Hepatite B/sangue , Vírus da Hepatite B/imunologia , Humanos , Índia , Dados de Sequência Molecular , Mutação , Filogenia , Regiões Promotoras Genéticas
9.
Mol Cell Biochem ; 360(1-2): 35-45, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21918828

RESUMO

Most clinical trials with vitamin E could not lower cholesterol and thus, have been deemed unsuccessful. Recently, tocotrienols, isomers of vitamin E have been found to lower LDL levels. To explore if tocotrienols could be the drug target for vitamin E, rabbits were kept on cholesterol diet for 60 days supplemented with tocotrienol-α, tocotrienol-δ, and tocotrienol-γ for the last 30 days. The serum cholesterol levels (in mmol/l) were 24.4 (tocotrienol-α), 34.9 (tocotrienol-δ), 19.8 (tocotrienol-γ) vs. 39.7 (control). Left ventricular function including aortic flow and developed pressure exhibited significantly improved recovery with tocotrienol-γ and -α, but not with tocotrienol-δ. The myocardial infarct size showed a similar pattern: 33% (tocotrienol-α), 23% (tocotrienol-γ), and 47% (tocotrienol-δ). To examine the molecular mechanisms of cardioprotective effects, gene expression profile was determined using Atlas 1.2/1.2II followed by determination of gene profiles using PedQuest 8.3 software. Based on genomic profiles, the following cholesterol-related proteins were examined: FABP, TGF-ß (cholesterol suppresses TGF-ß), ET-1 (increased by hypercholesterolemia), SPOT 14 (linked with hypercholesterolemia), and matrix metalloproteinase (MMP) 2 and MMP9 (cholesterol regulates MMP2 and MMP9 expression) in the heart. Consistent with the cardioprotective effects of tocotrienol-α and -γ, these two isomers reduced ET-1, decreased MMP2 and MM9, increased TGF-ß and reduced SPOT 14, while tocotrienol-δ had no effects. The results of the present study demonstrate that the two isomers of tocotrienols, α and γ, render the hypercholesterolemic hearts resistant to ischemic reperfusion injury by lowering several hypercholesterolemic proteins including MMP2, MMP9, ET-1, and SPOT 14 and upregulating TGF-ß.


Assuntos
Anticolesterolemiantes/uso terapêutico , Cardiotônicos/uso terapêutico , Cromanos/uso terapêutico , Hipercolesterolemia/tratamento farmacológico , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Vitamina E/análogos & derivados , Animais , Aterosclerose/etiologia , Aterosclerose/prevenção & controle , Colesterol/sangue , Dieta Hiperlipídica , Endotelina-1/genética , Endotelina-1/metabolismo , Feminino , Expressão Gênica/efeitos dos fármacos , Perfilação da Expressão Gênica , Coração/efeitos dos fármacos , Hipercolesterolemia/sangue , Hipercolesterolemia/complicações , Técnicas In Vitro , Masculino , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/genética , Metaloproteinase 9 da Matriz/metabolismo , Traumatismo por Reperfusão Miocárdica/etiologia , Traumatismo por Reperfusão Miocárdica/patologia , Miocárdio/patologia , Coelhos , Ratos , Ratos Sprague-Dawley , Receptores de Estrogênio/genética , Receptores de Estrogênio/metabolismo , Fatores Sexuais , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/metabolismo , Vitamina E/uso terapêutico
10.
Gastroenterol Hepatol Bed Bench ; 15(4): 377-386, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36762226

RESUMO

Aim: This study is an attempt to screen the key immune elements that participate during HBV infection and the related pathways that are modulated. Background: The pathogenesis of Hepatitis B virus and the corresponding clinical manifestations in the host are primarily immune-mediated. Methods: This study utilizes a PCR array to screen immune-related genes that are differentially expressed in the presence of the virus in HBV replicating HepG2.2.15 cells as compared to control HepG2 cells. The significantly up-regulated genes were subjected to bioinformatic analysis utilizing GSEA and STRING. Additionally, ELISA was used to corroborate the levels of Alpha 1 antitrypsin (AAT) from patients' sera. Results: The expressions of 31% of the studied genes were significantly up-regulated (> 2-fold, p<0.05) in HepG2.2.15 cells compared to controls, and this included the SERPINA1, FN1, IL1R2, LBP, LY96, LYZ and PROC genes. When they were clustered based on biological processes, signaling pathways, and disease progression, the genes related to biotic stimulus, complement-coagulation cascades, and fibrosis, respectively, showed the highest (p<0.05) enrichment. Analysis of patients' sera by ELISA revealed that the serum AAT (SERPINA1) levels were significantly higher in asymptomatic carriers and in patients with chronic liver disease than in controls (p<0.05). Moreover, SERPINA1 levels were also positively correlated with the levels of serum ALT (r=0.4495, p<0.05) among HBV infected patients. Conclusion: The current study highlights the key immune elements and pathways that are modulated during HBV infection and proposes the possible use of AAT as a non-invasive immunological biomarker to follow the progression of liver disease.

11.
Hum Genet ; 130(6): 735-48, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21643982

RESUMO

To understand the importance of chr11q22.3-23.2 region in the development of cervical cancer, we have studied the genetic and epigenetic alterations of the candidate genes ATM, PPP2R1B, SDHD and CADM1 in cervical intraepithelial neoplasia (CIN) and cervical carcinoma (CACX) samples. Our study revealed low expression and high alterations (methylation/deletion) (55-59%) of ATM and CADM1 genes along with poor patient outcome. The alterations of ATM and CADM1 are associated with the progression of tumor from CIN to Stage I/II, thus implying their role in early invasiveness. The two genes, PPP2R1B and SDHD, lying in between ATM and CADM1, have low frequency of alterations, and majority of the alterations are in CACX samples, indicating that their alterations might be associated with disease progression. Expressions (mRNA/protein) of the genes showed concordance with their molecular alterations. Significant co-alteration of ATM and CADM1 points to their synergic action for the development of CACX. Mutation is, however, a rare phenomenon for inactivation of ATM. Association between the alteration of ATM and CHEK1 and poor survival of the patients having co-alterations of ATM and CHEK1 points to the DNA damage response pathway disruption in development of CACX. Thus, our data suggest that inactivation of ATM-CHEK1-associated DNA damage response pathway and CADM1-associated signaling network might have an important role in the development of CACX.


Assuntos
Moléculas de Adesão Celular/genética , Proteínas de Ciclo Celular/genética , Aberrações Cromossômicas , Cromossomos Humanos Par 11 , Proteínas de Ligação a DNA/genética , Imunoglobulinas/genética , Proteínas Serina-Treonina Quinases/genética , Proteínas Supressoras de Tumor/genética , Displasia do Colo do Útero/genética , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/patologia , Proteínas Mutadas de Ataxia Telangiectasia , Molécula 1 de Adesão Celular , Moléculas de Adesão Celular/biossíntese , Proteínas de Ciclo Celular/biossíntese , Linhagem Celular Tumoral , Quinase 1 do Ponto de Checagem , Dano ao DNA , Metilação de DNA , Proteínas de Ligação a DNA/biossíntese , Progressão da Doença , Epigenômica/métodos , Feminino , Regulação Neoplásica da Expressão Gênica , Células HeLa , Humanos , Imunoglobulinas/biossíntese , Mutação , Estadiamento de Neoplasias , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/genética , Infecções por Papillomavirus/metabolismo , Infecções por Papillomavirus/patologia , Regiões Promotoras Genéticas , Proteínas Quinases/genética , Proteína Fosfatase 2/biossíntese , Proteína Fosfatase 2/genética , Proteínas Serina-Treonina Quinases/biossíntese , Transdução de Sinais , Proteínas Supressoras de Tumor/biossíntese , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/virologia , Displasia do Colo do Útero/patologia , Displasia do Colo do Útero/virologia
12.
J Med Virol ; 83(2): 253-60, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21181919

RESUMO

Mutations in the basal core promoter (BCP) and precore (PC) regions are associated with persistent and intermittently high hepatitis B virus (HBV) replication in several patients. The variability in the functional domains of BCP and PC region of HBV and their association with disease progression and clinical outcome were assessed in Eastern India, an unique region where three HBV genotypes, A, D, and C are prevalent among the same ethnic group. PCR amplification and direct sequencing of BCP and PC region was done on sera obtained from 130 HBsAg positive subjects with different clinical presentations. Associations of the apparent risk factors with clinical advancement were evaluated by statistical methods including multiple logistic regression analyses (MLR). HBV genotype A was present in 33.08%, C in 25.38%, and D in 41.54% cases. Genotypes A and C were associated with higher rate of T1762/A1764 mutations than the most predominant genotype D. HBeAg negative state was associated with considerably higher rate of C1753 mutation. T1762/A1764 along with C1753 was common among cirrhosis and T1762/A1764 without C1753 was frequent among chronic liver disease cases. No significant association was found between A1896 point mutation and clinical status. Multivariate analysis revealed that T1762/A1764 double mutation, HBV/A, age ≥25 years, C1753 and A1899 were critical factors for clinical advancement while age ≥25 years and C1753 as significant predictor for cirrhosis in comparison with chronic liver disease. In conclusion, the analysis of the BCP variability may help in monitoring the progression towards advanced liver disease in Eastern Indian patients.


Assuntos
Vírus da Hepatite B/genética , Hepatite B/epidemiologia , Hepatite B/virologia , Adulto , Progressão da Doença , Etnicidade , Feminino , Marcadores Genéticos/genética , Variação Genética , Hepatite B/diagnóstico , Antígenos do Núcleo do Vírus da Hepatite B/genética , Antígenos E da Hepatite B/genética , Vírus da Hepatite B/patogenicidade , Interações Hospedeiro-Patógeno , Humanos , Índia/epidemiologia , Cirrose Hepática/patologia , Masculino , Pessoa de Meia-Idade , Mutação Puntual , Regiões Promotoras Genéticas/genética , Fatores de Risco
13.
J Virol ; 83(19): 9983-92, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19420079

RESUMO

The compartmentalization of viral variants in distinct host tissues is a frequent event in many viral infections. Although hepatitis B virus (HBV) classically is considered hepatotropic, it has strong lymphotropic properties as well. However, unlike other viruses, molecular evolutionary studies to characterize HBV variants in compartments other than hepatocytes or sera have not been performed. The present work attempted to characterize HBV sequences from the peripheral blood leukocytes (PBL) of a large set of subjects, using advanced molecular biology and computational methods. The results of this study revealed the exclusive compartmentalization of HBV subgenotype Ae/A2-specific sequences with a potent immune escape G145R mutation in the PBL of the majority of the subjects. Interestingly, entirely different HBV genotypes/subgenotypes (C, D, or Aa/A1) were found to predominate in the sera of the same study populations. These results suggest that subgenotype Ae/A2 is selectively archived in the PBL, and the high prevalence of G145R indicates high immune pressure and high evolutionary rates of HBV DNA in the PBL. The results are analogous to available literature on the compartmentalization of other viruses. The present work thus provides evidence in favor of the compartment-specific abundance, evolution, and emergence of the potent immune escape mutant. These findings have important implications in the field of HBV molecular epidemiology, transmission, transfusion medicine, organ transplantation, and vaccination strategies.


Assuntos
Antígenos de Superfície da Hepatite B/genética , Vírus da Hepatite B/genética , Hepatite B/virologia , Leucócitos/virologia , Mutação , Adolescente , Adulto , Ensaio de Imunoadsorção Enzimática , Evolução Molecular , Variação Genética , Genótipo , Hepatite B/genética , Humanos , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Prevalência
14.
Virol J ; 7: 204, 2010 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-20799931

RESUMO

BACKGROUND: Occult hepatitis B virus (HBV) infection might transmit viremic units into the public blood supply if only hepatitis B surface antigen (HBsAg) testing is used for donor screening. Our aim was to evaluate the prevalence of occult HBV infection among the HBsAg negative/antiHBc positive donations from a highly HIV prevalent region of India. METHODS: A total of 729 HBsAg negative donor units were included in this study. Surface gene and precore region were amplified by in house nucleic acid test (NAT) for detection of occult HBV infection and surface gene was analyzed after direct sequencing. RESULTS: A total of 220 (30.1%) HBsAg negative donors were antiHBc positive, of them 66 (30%) were HBV DNA positive by NAT. HBV DNA positivity among 164 antiHBc only group, was 27.1% and among 40 antiHBs positive group was 30.0%. HBV/D (93.3%) was predominant and prevalence of both HBV/C and HBV/A was 3.3%. Single or multiple amino acids substitutions were found in 95% samples. CONCLUSION: Thus, a considerable number of HBV infected donors remain undiagnosed, if only HBsAg is used for screening. Addition of antiHBc testing for donor screening, although will lead to rejection of a large number of donor units, will definitely eliminate HBV infected donations and help in reducing HBV transmission with its potential consequences, especially among the immunocompromised population. The HBV genetic diversity found in this donor population are in accordance with other parts of India.


Assuntos
Doadores de Sangue , DNA Viral/sangue , Anticorpos Anti-Hepatite B/sangue , Hepatite B/diagnóstico , Hepatite B/epidemiologia , Técnicas de Amplificação de Ácido Nucleico/métodos , Virologia/métodos , Adulto , Feminino , Antígenos do Núcleo do Vírus da Hepatite B/imunologia , Vírus da Hepatite B/genética , Vírus da Hepatite B/imunologia , Vírus da Hepatite B/isolamento & purificação , Humanos , Índia/epidemiologia , Masculino , Programas de Rastreamento/métodos , Prevalência
15.
Hepatol Res ; 39(1): 53-9, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18713275

RESUMO

AIM: To screen hepatitis B virus (HBV) genotypes and associated basal core promoter (BCP; T1762/A1764) and precore (PreC; A1896) mutations among the HBV surface antigen (HBsAg) positive voluntary blood donors in eastern India. METHODS: HBV genotypes, BCP and PreC mutations of 141 HBsAg positive voluntary blood donors were determined by the restriction fragment length polymorphism (RFLP) method and a phylogenetic tree was constructed from surface (S) gene region sequences of representative HBsAg positive donors to confirm the results. RESULTS: HBV/D was the most predominant (79, 56.0%) genotype followed by HBV/C (33, 23.4%) and HBV/A (29, 20.6%). HBV/C infected blood donors are mostly young (18-25 years). The occurrence of BCP mutation was found to be significantly higher in HBV/C (24, 72.7%) than in HBV/A (7, 24.1%, P < 0.001) and HBV/D (17, 21.5%, P < 0.001), whereas PreC mutation was more frequent in HBV/D (28, 35.4%) than in HBV/C (9, 27.3%). However, the simultaneous presence of BCP and PreC mutations was more common in HBV/C (8/33, 24.2%), followed by HBV/D (6/79, 7.6%). CONCLUSION: In addition to HBV/D and HBV/A, a significant proportion of HBV/C (23.4%) was also present among the voluntary blood donors from eastern India, most frequently in the 18-25 year age group. BCP mutation was more common in HBV/C infected donors.

16.
Intervirology ; 51(4): 275-84, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18987483

RESUMO

OBJECTIVES: This unmatched case-control study aimed at determining the molecular epidemiology and clinical significance of HBV genotypes, core promoter (CP) and precore (PC) mutations in Eastern India. METHODS: Serological, biochemical and molecular assays were used to examine antigens, ALT, genotypes, mutations and viremia among 106 inactive carriers and 183 chronic liver disease (CLD) patients. RESULTS: Male gender (p < 0.001), HBeAg positivity (p = 0.050), high ALT (p < 0.001), high viremia (p < 0.001), CP mutations (p < 0.001), and genotypes A (p < 0.001) and C (p = 0.027) were significantly associated with CLD. Subjects infected with genotypes A and C had significantly higher prevalence of BCP mutations (p < 0.001), and low incidence of PC mutation (p < 0.001 and p = 0.047, respectively). Prevalence of genotype D was significantly higher among subjects with history of familial/childhood jaundice, while genotypes A and C were frequent among subjects with possible percutaneous exposure. CONCLUSIONS: Significant differences in risk factors and disease manifestation do exist among patients infected with different HBV genotypes. Genotypes A and C are frequently found among chronic liver disease patients, while genotype D is associated with inactive HBeAg-negative infections. This evaluation of clinical relevance of HBV genotypes, mutations and risk factors may be useful in disease prognosis, management and prevention strategies.


Assuntos
Antígenos do Núcleo do Vírus da Hepatite B/genética , Vírus da Hepatite B/classificação , Vírus da Hepatite B/genética , Hepatite B Crônica/epidemiologia , Hepatite B Crônica/virologia , Mutação , Adulto , Alanina Transaminase/sangue , Estudos de Casos e Controles , Feminino , Genótipo , Antígenos da Hepatite B/sangue , Humanos , Índia/epidemiologia , Fígado/patologia , Masculino , Pessoa de Meia-Idade , Epidemiologia Molecular , Viremia
17.
J Coll Physicians Surg Pak ; 18(11): 688-94, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18983792

RESUMO

OBJECTIVE: To identify the distribution pattern of Hepatitis B Virus (HBV) genotype in a group of patients and to study its phylogenetic divergence. STUDY DESIGN: An observational study. PLACE AND DURATION OF STUDY: The clinics of Gastroenterology Unit, Ziauddin University, from January to December 2006. METHODOLOGY: Two hundred and one HBV infected patients were genotyped for this study. All HbsAg positive individuals, either healthy carriers or suffering from conditions such as acute or chronic hepatitis, cirrhosis and hepatocellular carcinoma were included. Hepatitis B patients co-infected with other hepatic viruses were excluded. Hepatitis B virus DNA was extracted from serum, and subjected to a nested PCR, using the primers type-specific for genotype detection. Phylogenetic analysis was performed in the pre-S1 through S genes of HBV. The divergence was studied through 15 sequences of 967 bp submitted to the DBJ/EMBL/GenBank databases accessible under accession number EF584640 through EF584654. RESULTS: Out of 201 patients tested, 156 were males and 45 were females. Genotype D was the predominant type found in 128 (64%) patients followed by A in 47 (23%) and mixed A/D in 26 (13%). Phylogenetic analysis confirmed the dominance of genotype D and subtype ayw2. CONCLUSION: There was dominance of genotype D subtype ayw2. It had a close resemblance with HBV strains that circulate in Iran, India and Japan.


Assuntos
Vírus da Hepatite B/genética , Hepatite B/genética , Filogenia , DNA Viral/genética , Feminino , Genótipo , Hepatite B/sangue , Hepatite B/epidemiologia , Anticorpos Anti-Hepatite B/genética , Humanos , Masculino , Epidemiologia Molecular , Mutação , Paquistão/epidemiologia , Projetos Piloto
18.
Indian J Med Microbiol ; 36(2): 217-223, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30084414

RESUMO

Background: Combination of tenofovir disoproxil fumarate (TDF), lamivudine (3TC) and efavirenz (EFV) is preferred in the treatment of HIV/hepatitis B virus (HBV) coinfection. We postulated that a HBV active nucleoside reverse transcriptase (RT) inhibitor/nucleotide RT inhibitor backbone of adefovir dipivoxil (ADV) +3TC would be as effective as TDF +3TC for the Indian population. Objective: ADV + 3TC could be an alternative option for these HIV/HBV coinfected individuals, preserving the dually active TDF + 3TC as second-line nucleoside backbone following failure of the first-line ART. Materials and Methods: This randomised control trial (CTRI/2012/03/002471) was carried out at the ART Centre of Calcutta School of Tropical Medicine, India. Seventy-eight (39 on each arm) treatment-naïve HIV/HBV coinfected patients were randomised to receive either the combination of lamivudine + tenofovir + EFV or lamivudine + adefovir + zidovudine + EFV and followed up for 120 weeks. Results: Median age of the study participants was 36 years (21-62), majority were male (61/78; 78.2%) and heterosexually (39/78; 50%) infected. Baseline characteristics were identical in both arms. There was no statistically significant difference in median aspartate aminotransferase (37 vs. 29.5 U/L), alanine aminotransferase (ALT) (36 vs. 34.5 U/L), ALT normalisation rate (80 vs. 70%), AST to platelet ratio index (0.45 vs. 0.33), CD4 count (508 vs. 427 cells/mm3), HBV DNA suppression (81.8 vs. 70%), hepatitis B e antigen loss (9 vs. 5%), hepatitis B surface antigen seroclearance rate (6.06 vs. 18.75%) and death (3 vs. 3) at 120 weeks between TDF (n = 33) and ADV (n = 32), respectively. Conclusions: Adefovir plus lamivudine is an effective alternative of tenofovir plus lamivudine in long-term HBV treatment outcome in HIV/HBV coinfected patients.


Assuntos
Adenina/análogos & derivados , Fármacos Anti-HIV/uso terapêutico , Antivirais/uso terapêutico , Coinfecção/tratamento farmacológico , Infecções por HIV/tratamento farmacológico , Hepatite B/tratamento farmacológico , Lamivudina/uso terapêutico , Organofosfonatos/uso terapêutico , Tenofovir/uso terapêutico , Adenina/uso terapêutico , Adulto , Feminino , Vírus da Hepatite B/efeitos dos fármacos , Vírus da Hepatite B/patogenicidade , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
19.
J Clin Virol ; 40(3): 255-8, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17869170

RESUMO

BACKGROUND: In blood donors, HBV infection is detected by the presence of serum hepatitis B surface antigen (HBsAg). However, some mutations in the surface gene region may result in altered or truncated HBsAg that can escape from immunoassay-based diagnosis. Such diagnostic escape mutants pose a potential risk for blood transfusion services. RESULTS: In the present study, we report a blood donor seronegative for HBsAg and antiHBc, but positive for antiHBs who was HBV DNA positive by PCR. Sequencing of the HBsAg gene revealed presence of a point mutation (T-A) at 207th nucleotide of the HBsAg ORF, which resulted in a premature stop codon at position 69. This results in a truncated HBsAg gene lacking the entire 'a' determinant region. However, follow-up of the donor after 2 years revealed clearance of HBV DNA from the serum. CONCLUSION: The case illustrates an unusual mutation, which causes HBsAg negativity. The finding emphasizes the importance of molecular assays in reducing the possibility of HBV transmission through blood transfusion. However, developing more sensitive serological assays, capable of detecting HBV mutants, is an alternative to expensive and complex amplification-based assays for developing countries.


Assuntos
Doadores de Sangue , Códon de Terminação/genética , Anticorpos Anti-Hepatite B/sangue , Antígenos do Núcleo do Vírus da Hepatite B/imunologia , Antígenos de Superfície da Hepatite B , Hepatite B/virologia , Adulto , DNA Viral/análise , DNA Viral/sangue , Antígenos do Núcleo do Vírus da Hepatite B/genética , Antígenos de Superfície da Hepatite B/sangue , Antígenos de Superfície da Hepatite B/genética , Vírus da Hepatite B/genética , Vírus da Hepatite B/isolamento & purificação , Humanos , Masculino , Dados de Sequência Molecular , Mutação , Filogenia , Reação em Cadeia da Polimerase/métodos , Análise de Sequência de DNA
20.
J Clin Virol ; 40(4): 312-7, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17997353

RESUMO

BACKGROUND: Genetic mutation might account for the presence of hepatitis B virus (HBV) DNA among antiHBc only individuals. The aim of the study was to assess the prevalence and significance of surface gene mutations among antiHBc only cases in our population. METHODS: Three hundred and three antiHBc(+) sera of adults (mean age, 33.7+/-11.0; range 18-65 years) as well as HBsAg(+)/HBV DNA(+) (n=19) controls were included in this study. Surface gene and basal core promoter (BCP)-precore region were amplified and surface gene was analyzed after direct sequencing. RESULTS: One hundred and seventy-eight out of 303 (58.8%) was antiHBc only, 39/171 (22.8%) of them was HBV DNA(+). Genotypes A, C, D were found among both HBsAg(+) and antiHBc(+) samples. Single or multiple amino acids substitutions were found in 82% samples, however, G145R vaccine escape mutation was rare. Individuals having substitutions within as well as outside major hydrophilic loop (MHL) region were detected; some of these mutations were in overlapping RT domain of polymerase (Pol) gene. CONCLUSIONS: The existence of occult HBV infection among antiHBc only individuals could not be explained fully by mutations in the 'a' determinant region of surface gene in our population.


Assuntos
Anticorpos Anti-Hepatite B/sangue , Antígenos de Superfície da Hepatite B/genética , Vírus da Hepatite B/genética , Hepatite B/virologia , Mutação , Adolescente , Adulto , Idoso , Substituição de Aminoácidos , Feminino , Genótipo , Hepatite B/epidemiologia , Hepatite B/imunologia , Anticorpos Anti-Hepatite B/imunologia , Antígenos do Núcleo do Vírus da Hepatite B/imunologia , Antígenos de Superfície da Hepatite B/imunologia , Vírus da Hepatite B/imunologia , Humanos , Índia/epidemiologia , Masculino , Pessoa de Meia-Idade , Prevalência
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