The Epstein-Barr virus (EBV) is a gamma herpes virus associated with several types of malignancies. The EBV encodes viral microRNAs (miRNAs) that can target genes within cells. The EBV participates in signal transduction as well as the proliferation and differentiation of cells. How the target genes and functions of EBV-encoded miRNAs contribute to the pathogenesis of EBV is an important research topic. Some target genes have been validated since EBV-encoded miRNAs were discovered and, in this article, we summarize them and their functions.
Animals ; Epstein-Barr Virus Infections ; genetics ; metabolism ; virology ; Herpesvirus 4, Human ; genetics ; physiology ; Humans ; MicroRNAs ; genetics ; metabolism ; RNA, Viral ; genetics ; metabolism

Latent Epstein-Barr virus (EBV) infection has a substantial role in causing many human disorders. The persistence of these viral genomes in all malignant cells, yet with the expression of limited latent genes, is consistent with the notion that EBV latent genes are important for malignant cell growth. While the EBV-encoded nuclear antigen-1 (EBNA-1) and latent membrane protein-2A (LMP-2A) are critical, the EBNA-leader proteins, EBNA-2, EBNA-3A, EBNA-3C and LMP-1, are individually essential for in vitro transformation of primary B cells to lymphoblastoid cell lines. EBV-encoded RNAs and EBNA-3Bs are dispensable. In this review, the roles of EBV latent genes are summarized.
Epstein-Barr Virus Infections/complications/virology ; Epstein-Barr Virus Nuclear Antigens/genetics/metabolism ; *Genes, Viral ; Herpesvirus 4, Human/*physiology ; Humans ; MicroRNAs/genetics ; Neoplasms/etiology ; Protein Binding ; RNA, Viral/genetics ; Viral Matrix Proteins/genetics/metabolism ; *Virus Latency

A small set of gastric adenocarcinomas (9%) harbor Epstein-Barr virus (EBV) DNA within malignant cells, and the virus is not an innocent bystander but rather is intimately linked to pathogenesis and tumor maintenance. Evidence comes from unique genomic features of host DNA, mRNA, microRNA and CpG methylation profiles as revealed by recent comprehensive genomic analysis by The Cancer Genome Atlas Network. Their data show that gastric cancer is not one disease but rather comprises four major classes: EBV-positive, microsatellite instability (MSI), genomically stable and chromosome instability. The EBV-positive class has even more marked CpG methylation than does the MSI class, and viral cancers have a unique pattern of methylation linked to the downregulation of CDKN2A (p16) but not MLH1. EBV-positive cancers often have mutated PIK3CA and ARID1A and an amplified 9p24.1 locus linked to overexpression of JAK2, CD274 (PD-L1) and PDCD1LG2 (PD-L2). Multiple noncoding viral RNAs are highly expressed. Patients who fail standard therapy may qualify for enrollment in clinical trials targeting cancer-related human gene pathways or promoting destruction of infected cells through lytic induction of EBV genes. Genomic tests such as the GastroGenus Gastric Cancer Classifier are available to identify actionable variants in formalin-fixed cancer tissue of affected patients.
Adenocarcinoma/*diagnosis/*etiology/therapy ; DNA Methylation ; Epstein-Barr Virus Infections/*complications ; Gene Expression Profiling ; Gene Expression Regulation, Neoplastic ; Gene Expression Regulation, Viral ; *Genomics/methods ; Herpesvirus 4, Human/*physiology ; Host-Pathogen Interactions/genetics ; Humans ; MicroRNAs/genetics ; Mutation ; RNA, Messenger/genetics ; Signal Transduction ; Stomach Neoplasms/*diagnosis/*etiology/therapy ; Virus Integration

Killer cell immunoglobulin-like receptors (KIRs) which are mainly expressed on natural killer (NK) cells are implicated in many virus infections. However, it is unclear whether or not KIRs are associated with susceptibility to Epstein-Barr virus (EBV) infection related diseases. Therefore, the purpose of our study was to investigate possible correlation between polymorphisms of KIR genes and infectious mononucleosis (IM)/EBV-associated hemophagocytic lymphohistiocytosis (EBV-HLH). The polymorphisms of KIR genes were detected by polymerase chain reaction with sequence-specific primers (PCR-SSP). The results would contribute to clarify the association of KIRs with EBV induced diseases, and provide new insights into the role of NK cells and innate immune response against viral infections and/or subsequent progression.
Case-Control Studies ; Child ; Child, Preschool ; China ; Disease Progression ; Female ; Herpesvirus 4, Human ; physiology ; Humans ; Immunity, Innate ; Infectious Mononucleosis ; genetics ; immunology ; virology ; Killer Cells, Natural ; immunology ; metabolism ; Lymphohistiocytosis, Hemophagocytic ; genetics ; immunology ; virology ; Male ; Polymerase Chain Reaction ; Polymorphism, Genetic ; Receptors, KIR ; genetics ; metabolism

Epstein-Barr virus (EBV) is a human herpesvirus associated with important human diseases, including infectious mononucleosis syndrome, malignant lymphoma, and nasopharyngeal carcinoma. The mechanism of EBV entry into host cells remains a subject of intensive research. After decades of study, researchers have identified several key proteins and different patterns of EBV intrusion into host cells. The viral surface glycoproteins, gp350/220, gp42, gB, gH, and gL, are involved in interactions with the CR2 receptor on the surface of B lymphocytes during viral entry. However, the majority of epithelial cells lack CR2 receptor expression, which makes viral invasion much more complex than in B lymphocytes. Three different models have been proposed to explain how EBV enters epithelial cells: (1) "transfer of infection", mediated by B lymphocytes or Langerhans cells; (2) EBV utilizes its own proteins during the process of fusion with the cell membrane; and (3) progeny virions arising from EBV-infected epithelial cells cross lateral membranes into adjacent epithelial cells. This review will discuss the relevant mechanism of viral entry into B lymphocytes and epithelial cells during EBV infection.
Animals ; B-Lymphocytes ; virology ; Epithelial Cells ; virology ; Epstein-Barr Virus Infections ; virology ; Herpesvirus 4, Human ; genetics ; physiology ; Humans ; Viral Proteins ; genetics ; metabolism ; Virus Internalization

This study aims to investigate the genetic characteristics of BZLF1 gene and its promoter Zp of the epidemic strains in children with primary Epstein-Barr virus (EBV)-associated diseases. Total DNA was extracted from the peripheral blood of 134 children with EBV-associated infectious mononucleosis (EBV-IM) and 32 children with EBV-associated hemophagocytic lymphohistiocytosis (EBV-HLH) who were admitted to Beijing Children's Hospital from 2006 to 2011. The EBNA3C, BZLF1, and Zp genes were amplified by PCR assay. Typing of EBV was performed according to the size of the amplification product of EBNA3C gene; the amplification products of BZLF1 and Zp genes were subjected to direct sequencing, and sequence analysis was performed using BioEdit 7. 0. 9. The results were as follows: (1) EBV-1 was present in 140 samples (97.2%, 140/144) and EBV-II in 4 samples (2.8%, 4/144). (2) Three BZLF1 genotypes and their 12 subtypes (including 6 newly found subtypes) were detected in this study; there were no significant differences in the frequencies of BZLF1-A and BZLF1-B between the children with EBV-IM and EBV-HLH (P = 0.083); BZLF1-A1 was the dominant genotype in children with EBV-associated diseases; t BZLF1-A mostly had three 29-bp repeats in the first intron of BZLF1 gene, and BZLF1-B mostly had 30-bp repeats (P = 0.000), with the number of repeats varying from 1 to 13. (3) Four Zp genotypes were detected in this study, including Zp-P, Zp-V3, Zp-V4, and Zp-V1; there were no significant differences in the frequencies of these Zp genotypes between children with EBV-IM and EBV-HLH (P = 0.272, 0.252, 1.0, and 1.0, respectively). (4) The linkage analysis of BZLF1 gene and its promoter Zp showed that BZLF1-A1 was highly associated with Zp-V3 (P = 0.000), while BZLF1-B4 with Zp-P (P = 0.000); EBV-I + BZLF1 A1 was highly associated with Zp-V3 (P = 0.000), while EBV-I+BZLF1-B4 with Zp-P (P = 0.000). The conclusions are as follows: (1) BZLF1-A1 is the dominant genotype in children with EBV-associated diseases; there are mostly 29-bp repeats in the first intron of BZLF1 gene for BZLF1-A genotype and 30-bp repeats for BZLF1-B genotype. (2) Zp-P and Zp-V3 are dominant Zp genotypes of EBV in children, which shared similar detection rates. (3) BZLF1-A1 is highly associated with Zp-V3, while BZLF1-B4 with Zp-P; EBV-I+BZLF1-A1 is highly associated with Zp-V3, while EBV-I+BZLF1-B4 with Zp-P.
Child ; Child, Preschool ; China ; epidemiology ; Epstein-Barr Virus Infections ; epidemiology ; virology ; Female ; Genotype ; Herpesvirus 4, Human ; genetics ; physiology ; Humans ; Infant ; Infant, Newborn ; Introns ; genetics ; Male ; Promoter Regions, Genetic ; genetics ; Repetitive Sequences, Nucleic Acid ; genetics ; Trans-Activators ; genetics

Antigens, Viral ; genetics ; metabolism ; Cell Line ; Cell Phone ; Gene Expression Regulation, Viral ; radiation effects ; Herpesvirus 4, Human ; physiology ; radiation effects ; Humans ; Immunohistochemistry ; Viral Proteins ; genetics ; metabolism

Epstein-Barr virus (EBV) microRNAs (miRNAs) are expressed in EBV-associated tumors and cell lines, but the regulation mechanism of their expression is unclear yet. We investigated whether the expression of EBV miRNAs is epigenetically regulated in EBV-infected B cell lines. The expression of BART miRNAs was inversely related with the methylation level of the BART promoter at both steady-state and following 5-aza-2'-deoxycytidine treatment of the cells. The expression of BHRF1 miRNAs also became detectable with the demethylation of Cp/Wp in latency I EBV-infected cell lines. Furthermore, in vitro methylation of the BART and Cp promoters reduced the promoter-driven transactivation. In contrast, tricostatin A had little effect on the expression of EBV miRNA expression as well as on the BART and Cp/Wp promoters. Our results suggest that promoter methylation, but not histone acetylation, plays a role in regulation of the EBV miRNA expression in EBV-infected B cell lines.
Azacitidine/analogs & derivatives/pharmacology ; B-Lymphocytes/metabolism/virology ; Cell Line ; *DNA Methylation ; DNA Modification Methylases/antagonists & inhibitors ; Gene Expression Regulation, Viral ; Gene Silencing ; Herpesvirus 4, Human/*genetics/physiology ; Humans ; MicroRNAs/genetics/*metabolism ; *Promoter Regions, Genetic ; RNA, Viral/genetics/*metabolism ; Viral Proteins/genetics

DNA Replication ; physiology ; Epstein-Barr Virus Infections ; virology ; Herpesvirus 4, Human ; genetics ; metabolism ; physiology ; Humans

OBJECTIVEImmortalized cell lines of spinocerebellar ataxia type 2 (SCA2) with Parkinson disease symptoms were established in order to provide experimental material for future study.

METHODSThe immortalized cell lines were constructed by using Epstein Barr virus and cyclosporine A. Microsatellite markers were detected to see whether there is any change between the cell lines and the original blood samples, and the genetic stability of the cell lines were evaluated.

RESULTSTwenty-five immortalized cell lines were established successfully from the family and the microsatellite markers were unchanged.

CONCLUSIONThe karyotypes of the immortal cell lines were normal and the cell lines were genetically stable.

Adult ; Asian Continental Ancestry Group ; genetics ; Cell Line, Transformed ; Cell Transformation, Viral ; Female ; Herpesvirus 4, Human ; physiology ; Humans ; Karyotyping ; Male ; Microsatellite Repeats ; Pedigree ; Spinocerebellar Ataxias ; genetics ; Young Adult