Project description:Most humans are infected with Epstein-Barr virus (EBV), a cancer-causing virus. While EBV generally persists silently in B lymphocytes, periodic lytic (re-)activation of latent virus is central to its life cycle and to most EBV-related diseases. However, a substantial fraction of EBV-infected B cells and tumor cells in a population is refractory to lytic activation. This resistance to lytic activation directly and profoundly impacts viral persistence and effectiveness of oncolytic therapy for EBV+ cancers. To identify the mechanisms that underlie susceptibility to EBV-lytic activation, we used host protein-expression profiling of separated-lytic and -refractory cells.
Project description:Most humans are infected with Epstein-Barr virus (EBV), a cancer-causing virus. While EBV generally persists silently in B lymphocytes, periodic lytic (re-)activation of latent virus is central to its life cycle and to most EBV-related diseases. However, a substantial fraction of EBV-infected B cells and tumor cells in a population is refractory to lytic activation. This resistance to lytic activation directly and profoundly impacts viral persistence and effectiveness of oncolytic therapy for EBV+ cancers. To identify the mechanisms that underlie susceptibility to EBV-lytic activation, we used host protein-expression profiling of separated-lytic and -refractory cells.
Project description:Burkitt lymphoma cells can be latently infected with Epstein-Barr virus (EBV). The virus may be activated into its lytic cycle by small molecules, such as sodium butyrate. Other molecules, such as valproate and valpromide, block viral lytic reactivation. These pharmacological agents alter the cellular physiology that controls viral lytic gene expression. Changes in the cellular transcription were measured in response to one activator and two inhibitors of the Epstein-Barr virus lytic cycle in order to identify cellular genes that are potential regulators of the viral life cycle.
Project description:Epstein-Barr virus (EBV) Rta is a latent-lytic molecular switch evolutionarily conserved in all gamma-herpesviruses. In previous studies, doxycycline-inducible Rta was shown to potently produce an irreversible G1 arrest followed by cellular senescence in 293 cells. Here, we demonstrate that in this system the inducible Rta not only reactivates resident genome of EBV but also that of Kaposi’s sarcoma-associated herpesvirus (KSHV), to similar efficiency. However, Rta-induced senescence program was terminated by the robust viral lytic cycle replication that eventually caused cell death. Furthermore, prior to the abrupt expression of immediate-early protein (EBV BZLF1 or KSHV RTA), Rta simultaneously down-regulates cell cycle activators (c-Myc, CDK6, CCND2) and up-regulates senescence-related genes (p21, 14-3-3s). Since Rta is a viral immediate-early transcriptional activator, it is envisioned that during the initial stage of viral reactivation, Rta may engage to modulate the host transcriptome, to halt cell cycle progression, and to maintain an ideal environment for manufacturing infectious virions. Refer to individual Series. This SuperSeries is composed of the following subset Series: GSE24585: Expression profiling of host genes modulated by Epstein-Barr virus (EBV) Rta in HEK293 cells GSE24586: Expression profiling of host genes modulated by Epstein-Barr virus Rta in nasopharyngeal carcinoma cells
Project description:RATIONALE: The Epstein Barr virus can cause cancer and lymphoproliferative disorders. Ganciclovir is an antiviral drug that acts against the Epstein Barr virus. Arginine butyrate may make virus cells more sensitive to ganciclovir. Combining ganciclovir and arginine butyrate may kill more Epstein Barr virus cells and tumor cells.
PURPOSE: Phase I trial to study the effectiveness of arginine butyrate plus ganciclovir in treating patients who have cancer or lymphoproliferative disorders that are associated with the Epstein Barr virus.
Project description:C7 is a novel lytic cycle inducer of Epstein-Barr virus (EBV) in EBV-positive epithelial cells. To analyze the potential signaling pathways that are activated by C7 for induction of EBV lytic cycle, we performed a RNA sequencing to analyze the RNA expression profiles in AGS-BX1 gastric carcinoma cells before and after treatment with C7.
Project description:Comparsion of cellular gene expression between a control B lymphoma cell-line (BJAB pz2) stably transfected with an empty vector and a BJAB cell-line stably expressing Epstein-Barr virus EBNA 3C (BJAB E3C-4). These cell lines are described in Wang, F., C. Gregory, C. Sample, M. Rowe, D. Liebowitz, R. Murray, A. Rickinson, and E. Kieff. 1990. Epstein-Barr virus latent membrane protein (LMP1) and nuclear proteins 2 and 3C are effectors of phenotypic changes in B lymphocytes: EBNA-2 and LMP1 cooperatively induce CD23. J Virol 64:2309-2318)