RESUMO
We determined the role of miR-520e in the replication of hepatitis B virus (HBV) and the growth of hepatocellular carcinoma (HCC) cells. MiR-520e and EPH receptor A2 (EphA2) in HBV-positive HCC tissues and cells were detected, and we studied the impact of miR-520e and the EphA2 receptor in cellular and murine HBV replication models. We find that MiR-520e was upregulated and EphA2 was downregulated in HBV-positive HCC tissues and cells. MiR-520e was decreased in Huh7-X and HepG2-X cells in which HBx was stably expressed, but was dose-dependently elevated after interfering with HBx. Additionally, miR-520e mimic and si-EphA2 groups were reduced in association with increases in HBV DNA content, HBsAg and HBeAg levels, cell proliferation and were enhanced in the expressions of EphA2, p-p38MAPK/p38MAPK, phosphorylated extracellular signal-regulated kinase 1/2 (p-ERK1/2)/ERK1/2 and cell apoptosis. Furthermore, si-EphA2 reversed the promotion effect of miR-520e inhibitor on HBV replication and tumour cell growth. Upregulating miR-520e in rAAV8-1.3HBV-infected mouse resulted in reduced EphA2 in liver tissues and HBV DNA content in serum. We find that MiR-520e was decreased in HBV-positive HCC, while overexpression of miR-520e blocked p38MAPK and ERK1/2 signalling pathways by an inhibitory effect on EphA2 and ultimately reduced HBV replication and inhibited tumour cell growth. These data indicate a role for miR-520e in the regulation of HBV replication.
Assuntos
Carcinoma Hepatocelular/virologia , Efrina-A2/metabolismo , Vírus da Hepatite B/fisiologia , Neoplasias Hepáticas/virologia , Sistema de Sinalização das MAP Quinases , MicroRNAs/metabolismo , Replicação Viral , Adulto , Animais , Apoptose , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Proliferação de Células , Efrina-A2/genética , Feminino , Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Inativação Gênica , Células Hep G2 , Antígenos de Superfície da Hepatite B/metabolismo , Antígenos E da Hepatite B/metabolismo , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Sistema de Sinalização das MAP Quinases/genética , Masculino , Camundongos , MicroRNAs/antagonistas & inibidores , MicroRNAs/genética , Pessoa de Meia-Idade , Receptor EphA2 , Transativadores/metabolismo , Proteínas Virais Reguladoras e AcessóriasRESUMO
Two experiments were used to examine the potential role of IFN-gamma in chickens infected with reticuloendotheliosis virus (REV) and Marek's disease virus (MDV). First, chickens were infected with REV and/or MDV at 5 days of age and examined from 3 to 50 days post-infection (dpi). In REV+MDV co-infection chickens, IFN-gamma ELISA demonstrated a 3-fold increase at 7 dpi compared to the controls, while REV alone caused a 5-fold increase, the IFN-gamma levels peaked, and then gradually decreased. IFN-gamma levels significantly decreased in MDV infection at 3 dpi and 15 dpi. Second, experiments were designed to determine the effects of different viruses and ConA on IFN-gamma production. For REV- or MDV-infected chickens, the IFN-gamma levels decreased slightly after adding ConA. This is the first report of IFN-gamma production in SPF chickens infected with REV and MDV measured by directly quantitative method.