RESUMO
BACKGROUND/AIMS: Hepatitis B virus (HBV) is the etiological factor for hepatocellular carcinoma (HCC). Numerous evidence has indicated a link between chronic infection with HBV and the development of HCC. Among the four proteins encoded by HBV, Hepatitis B virus X gene(HBx), best characterized as a transcriptional transactivator, gained attention owing to its presumptive role in oncogenesis. Further, HBx has been shown to stimulate signal transduction pathways such as Ras-MAPK pathway, NF-kappaB, and Src kinase. The pleiotropic events caused by HBx may be the key to understanding the HBV-mediated oncogenicity. However, the specific roles of HBx in oncogenesis remain largely elusive. To explore the role of HBx in hepatocarcinogenesis, we examined the deregulation of host genes induced by HBx expression. METHODS: HBx was ectopically expressed in HepG2 cells using a recombinant adenovirus to transiently express HBx. Gene expression profiling of HBx was conducted on cDNA microarrays that contained 1,028 cDNAs. RESULTS: A number of oncogenes and genes that are involved in cell growth, DNA repair, cell cycle regulation, and cell motility were deregulated by HBx. CONCLUSIONS: Theses results suggest that HBx regulates transcription in a way that contributes to the proliferation of hepatocytes, a probable early event of HCC.
Assuntos
Humanos , Carcinoma Hepatocelular/virologia , Linhagem Celular Tumoral , Resumo em Inglês , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Genes Virais/fisiologia , Vetores Genéticos , Antígenos da Hepatite B/genética , Vírus da Hepatite B/genética , Neoplasias Hepáticas/virologia , Análise de Sequência com Séries de Oligonucleotídeos , Transativadores/genéticaRESUMO
We made reporter HIV-1 DNA constructs carrying green fluorescent protein (GFP) gene and exchangeable env of subtype E. The recombinant constructs were used to produce infectious reporter viruses, which induced infected cells to emit green fluorescent light and rendered them easily detectable at single cell level. Because the env in this construct can be easily exchanged, viruses with different antigenic epitopes can be made. We used these reporter viruses to set up a neutralizing antibody assay based on fluorescence reduction by flow cytometric measurement. The result of this new assay correlated with the standard infectivity reduction assay using primary isolates. Because this new assay is faster and much less costly than the standard assay using a p24 endpoint and can be performed in peripheral blood mononuclear cells (PBMC), it provides a useful tool for analysis of HIV-1 immune responses.
Assuntos
Determinação de Ponto Final/métodos , Imunofluorescência/métodos , Genes Reporter/fisiologia , Genes Virais/fisiologia , Proteínas de Fluorescência Verde , HIV-1/genética , Humanos , Indicadores e Reagentes/análise , Proteínas Luminescentes/análise , Testes de Neutralização/métodos , Sensibilidade e Especificidade , Fatores de Tempo , Latência Viral/imunologiaRESUMO
A deteccao do DNA do Virus da Hepatite B pela Reacao em cadeia Polimerase (PCR) foi comparada com os outros marcadores sorologicos virais (AgHBs, AgHBe e anti-HBe) numa serie de 49 pacientes com hepatite cronica B, incluindo 12 que apresentaram clareamento espontaneo do AgHBs. Nenhum caso AgHBs negativo foi PCR positivo, mas 33/37 (89,2 por cento) dos casos AgHBs positivos foram PCR positivos (p<0,0001). Entre as amostras AgHBs positivas, 9 foram AgHBe positivas e anti-HBe negativas, todas elas PCR positivas....