جستجوی مقالات مرتبط با کلیدواژه « epstein–barr virus » در نشریات گروه « پزشکی »

MicroRNAs play important roles in regulating gene expression in animals and plants. Many studies used these genetic elements to up- or down-regulate human gene expression. It has been shown that viral miRNAs can target and regulate not only viral genes but also host genes. To date, 48 miRNAs have been identified in Epstein-Barr virus (human gamma-herpesvirus 4). This virus can invade and reside in many human tissues such as epithelial or immune system cells. In this study, we evaluated a novel method of finding miRNAs in the Epstein-Barr virus (EBV).

The entire genome content of human gamma-herpesvirus 4 (EBV) was searched using ab initio prediction algorithm by miRNAFold. Selected sequences screened by homology algorithm of miRBase web server.

Among the identified 12 sequences, two putative miRNAs were selected and their properties were further investigated. The main human gene target of the putative miRNA-1 was BCL11A gene that is related to the B-cell lymphoma, and that of putative miRNA-2 was ZBTB18 gene which is mainly related to the mental retardation.
Previous studies used known EBV miRNAs incorporated in delivering vectors such as lentiviral vectors to target various human genes. The introduced two miRNAs can target genes in some malignancies and other types of disorders.

Because of the high stability of the proposed putative miRNAs, they can be used experimentally to regulate human genes.

 Gastric cancer is the fourth leading cause of cancer-related deaths in the world. The identification of gastric cancer subtypes related to recognizable microbial agents may play a pivotal role in the targeted prevention and treatment of this cancer. The current study is conducted to define the frequency of Epstein-Barr virus (EBV) infection in gastric cancers of four major provinces, with different incidence rates of gastric cancers, in Iran.

 Paraffin blocks of 682 cases of various types of gastric cancer from Tehran, South and North areas of Iran were collected. Twelve tissue microarray (TMA) blocks were constructed from these blocks. Localization of EBV in tumors was assessed by in situ hybridization (ISH) for EBV-encoded RNA (EBER). Chi-squared test was used to evaluate the statistical significance between EBV-associated gastric cancer (EBVaGC) and clinicopathologic tumor characteristics.

 Fourteen out of 682 cases (2.1%) of gastric adenocarcinoma were EBER-positive. EBER was positive in 8 out of 22 (36.4%) of medullary carcinomas and 6 out of 660 (0.9%) of non-medullary type, which was a statistically significant difference (P<0.001). The EBVaGCs were more frequent in younger age (P=0.009) and also showed a trend toward the lower stage of the tumor (P=0.075).

 EBV-associated gastric adenocarcinoma has a low prevalence in Iran. This finding can be due to epidemiologic differences in risk factors and exposures, and the low number of gastric medullary carcinomas in the population. It may also be related to gastric tumor heterogeneity not detected with the TMA technique.

 Infection with Epstein-Barr virus (EBV) ranks as one of the most substantial risk factors associated with Glioblastoma multiforme (GBM). At the core of this intricate relationship lies the EBV nuclear antigen-1 (EBNA1) protein, a central figure with a remarkable ability to regulate the expression of both cellular and viral genes. This research delves into the impact of EBNA1 on the expression patterns of four cellular genes - MDMX, MDM2, MYC, and BIRC5 in the U87MG cell line.

 We divided U87MG cells into two distinct groups. The first group involved cells that were transfected with a plasmid containing the EBNA1 gene, while the second group consisted of cells that were transfected with a control plasmid. To evaluate the transcriptional activity of MDMX, MDM2, MYC, and BIRC5 genes in both sets of cells, we employed a real-time PCR technique. Any observed differences were considered statistically significant if the associated P-values were less than 0.05.

 Our findings demonstrated a substantial three-fold increase in the expression of the MDMX gene when U87MG cells were transfected with EBNA1 plasmid (P=0.02). Although the cells transfected with EBNA1 plasmid displayed great elevations in the expression levels of MDM2, MYC, and BIRC5 genes, these alterations were not statistically significant.

 The outcomes of this investigation have unveiled that EBNA1 has the ability to trigger the expression of four crucial cellular genes, which wield substantial influence in the genesis of GBM within glioblastoma astrocytoma cells. This underscores the potential impact of EBNA1 on the evolution of GBM, particularly in individuals harboring EBV.

Gastroenteritis is the second leading cause of death worldwide, with a high prevalence in children. Among pathogenic microorganisms, viruses are one of the main causes of this disease. Thus, the aim of this research was to investigate the prevalence of diarrhea caused by human adenovirus (HAdV), Epstein-Barr virus (EBV), and cytomegalovirus (CMV) in children with hematological diseases for the first time in Iran.

This study was conducted on 120 stool samples stored in the clinical sample bank of the Cellular and Molecular Research Center of Qom University of Medical Sciences. These samples were obtained from immunocompromised children with gastrointestinal symptoms, who referred to one of the children's hospitals in Qom during 2018 to 2019. Genomes were extracted from the stool samples and evaluated using the polymerase chain reaction (PCR) method.

The prevalence of HAdV and EBV was reported in seven (5.8%) and one (0.8%) cases, respectively, and CMV was detected in none of the samples. No cases of co-infection were observed.

This study results show that there are diarrhea-causing viruses among patients in the study area. Fortunately, the prevalence of these infectious agents in patients with underlying conditions was relatively low. However, monitoring of these viruses in the feces of all patients, especially immunocompromised patients, is recommended.

HERV-K env is associated with several neurological disorders, including MS. Clinical studies have demonstrated a plausible interaction between HERV-K env and other MS risk factors. The present study aimed to investigate the possible association between HERV-K18 env and TGF-β. We further assessed the in vitro effect of EBV infection on HERV-K18 env expression in the presence and absence of vitamin D in MS patients.

PBMCs from 20 MS patients and 20 healthy controls were infected with the B95.8 EBV, seeded into 24-well plates and incubated in the presence or absence of 100 nM of 1,25(OH)D3. The expression levels of HERV-K18 env and TGF-β were measured using real-time PCR.

While the expression level of HERV-K18 env was significantly higher in MS patients than the healthy controls, this trend for TGF-β was significantly reverse. Interestingly, an inverse correlation was found between HERV-K18 env and TGF-β expression in MS patients, although the in vitro stimulation of PBMCs with EBV and vitamin D showed no significant differences in terms of HERV-K18 expression.

Our findings highlight the potential role of HERV-K18 env in MS patients.

Hemophagocytic lymphohistiocytosis (HLH) is a fatal clinical syndrome. The most common cause of secondary HLH is Epstein-Barr virus (EBV) infection. EBV-HLH is a common clinical disease with high mortality, easy relapse, and poor prognosis. Therefore, treating EBV-HLH with T and B lymphocyte involvement is challenging, and selecting an appropriate treatment regimen is critical. Moreover, research on how to evaluate the recurrence index after remission is scarce. In this study, we reported a case of EBV-HLH successfully treated with programmed cell death protein-1 (PD-1) inhibitor in combination with rituximab. The regimen had a good curative effect, and we successfully detected the trend of early recurrence. Our findings indicated that PD-1 inhibitor in combination with rituximab may help to treat EBV-HLH and maintain EBV-infected T and B whole-line lymphocytes.

Epstein-Barr virus (EBV) represents one of the most important viral carcinogens. EBV nuclear antigen-1 (EBNA1) can induce the expression of different cellular and viral genes. In this study, we evaluated the EBNA1 effects on the expression patterns of human papillomavirus type 18 (HPV-18) E6 and E7 oncogenes and three cellular genes, including BIRC5, c-MYC, and STMN1, in a cervical adenocarcinoma cell line. HeLa cells were divided into three groups: one transfected with a plasmid containing the EBNA1 gene, one transfected with a control plasmid, and one without transfection. In all three groups, the expression levels of E6, E7, BIRC5, c-MYC, and STMN1 genes were checked using real-time PCR. Pathological staining was used to examine changes in cell morphology. Real-time PCR results showed that the expression level of HPV-18 E6 (P=0.02) and E7 (P=0.02) oncogenes significantly increased in HeLa cells transfected with the EBNA1 plasmid compared to cells transfected with control plasmid. Also, the presence of EBNA1 induced the expression of BIRC5 and c-MYC, which increased tenfold (P=0.03) and threefold (P=0.02), respectively. Regarding the STMN1 cellular gene, although the expression level in HeLa cells transfected with EBNA1 plasmid showed a twofold increase, this change was insignificant (P=0.11). Also, EBNA1 expression caused the creation of large HeLa cells with abundant cytoplasm and numerous nuclei. The EBV-EBNA1 could increase the expression levels of HPV-18 E6 and E7 viral oncogenes as well as c-MYC and BIRC5 cellular genes in the HeLa cell line. These findings indicate that the simultaneous infection of cervical cells with HPV-18 and EBV might accelerate the progression of cervical cancer.

Targeting the lytic cycle of the Epstein-Barr virus (EBV) has been considered a new treatment strategy for malignancies caused by this virus.  This study aimed to investigate the effect of Dendrosomal NanoCurcumin (DNC) to prevent cell transformation and inhibit the expression of viral lytic gene expression in the generation of lymphoblastoid cell line (LCL). Cell viability of LCLs and PBMCs was performed by MTT assay, and flow cytometry (Annexin/PI) was used for evaluation of apoptosis. CD markers on the surface of generated LCL (CD19) cells were examined for cell validation. The effect of DNC on transformation was evaluated by examining cell morphology and determining the expression level of lytic genes BZLF1, Zta, BHRF1, and BRLF1 of EBV using Real-time PCR. Student’s t-test was used for statistical analysis. The MTT assay showed that DNC can inhibit the proliferation of LCL in a dose-dependent manner. The 50% cytotoxic concentration (CC50) of DNC and curcumin for LCL was determined 38.8 µg/ml and 75 µg/ml, respectively after 72 hr. Also, Real-time PCR data analysis showed that DNC in 30 µg/ml concentration significantly inhibited cell transformation in the LCL and significantly reduced viral lytic genes such as BZLF1, Zta, BHRF1, and BRLF1expression compared to control. Overall, these findings show that DNC reduces the expression of the viral lytic cycle genes and also the induction of cell apoptosis and finally prevents the generation of LCL.

Usual neurological complications of Epstein-Barr virus infection are aseptic meningitis, encephalitis, transverse Usual neurological complications of Epstein-Barr virus infection are aseptic meningitis, encephalitis, transverse myelitis, cerebellitis, Guillain-Barre syndrome, and cranial or peripheral neuritis most commonly in immunocompromised patients. These clinical manifestations may occur alone or accompanied by infectious mononucleosis. Usually, EBV encephalitis occurs infrequently and with non-specific symptoms. Herein, we report two patients: a 24-year-old female with generalized tonic-clonic fever and seizures for ten days. The other was a 28-year-old male with repeated fever, headache, 4-day amnesia, and symptoms of meningeal irritation. Since the physical examination results were not very helpful, the definite diagnosis was achieved by sampling, analysis, and polymerase chain reaction for the cerebrospinal fluid. Our patients had a direct EBV invasion of the CNS and were affected by Epstein-Barr virus encephalitis, confirmed by their clinical test results as a positive polymerase chain reaction of cerebrospinal fluid. The PCR results were negative for a panel of microorganisms that cause bacterial meningitis in the CSF, but positive for EBV. Image findings also did not show any significant results. Patients treated with acyclovir and precision control at the relative center with favorable outcomes. Acyclovir possibly will lessen viral replication. Finally, despite obtaining negative test results of EBV infection, every therapeutic effort should be undertaken and maintained continuous attention.

Epstein-Barr virus nuclear antigen-1 (EBNA1) is one of the most important proteins of Epstein-Barr virus (EBV) that might be mutated in various related cancers. The purpose of this study was to compare EBNA1 mutations in the C-terminal region between patients with cervical and ovarian cancer and healthy individuals.

As test and control groups, 18 EBV-positive paraffin-embedded samples of cervical and ovarian cancer and 10 age- and gender-matched healthy volunteers who did not have cancer but were EBV-positive were both used. Utilizing a commercial DNA extraction kit, total DNA was extracted following deparaffinization. The entire C-terminal region of the EBNA1 sequence was amplified using an in-house nested PCR. Phylogenetic analysis and Sanger sequencing were used to analyze the sequences using MEGA 7 software and through NJ method.

Sequence analysis revealed that the P-Ala subtype of EBNA1 was present in all samples. In two and one samples, respectively, of cervical cancer patients, the mutations A1887G and G1891A were found. The G1595T mutation was also detected in four sequences taken from ovarian cancer patients. No statistically significant difference could be found between the frequency of mutations in patients and controls (P>0.05). No known amino acid substitutions were found in the USP7-binding region and the DBD/DD domain.

The findings showed that P-Ala is the predominant EBV subtype across all samples. Additionally, as the sequence of EBNA1's C-terminal region is so stable, it's possible that it had little impact on the pathogenesis of ovarian and cervical malignancies. It is advised to conduct additional research to verify these findings.

Suppression of p53 is an important mechanism in Epstein-Barr virus associate-tumors and described as EBNA1-USP7 which is a key axis in p53 suppression. Thus, in this study, we aimed to evaluate the function of EBNA1 on the expression of p53-inhibiting genes including HDAC-1, MDM2, MDM4, Sirt-3, and PSMD10 and the influence of USP7 inhibition using GNE-6776 on p53 at protein/mRNA level.

  The electroporation method was used to transfect the BL28 cell line with EBNA1. Cells with stable EBNA1 expression were selected by Hygromycin B treatment. The expression of seven genes, including PSMD10, HDAC-1, USP7, MDM2, P53, Sirt-3, and MDM4, was evaluated using a real-time PCR assay. For evaluating the effects of USP7 inhibition, the cells were treated with GNE-6776; after 24 hours and 4 days, the cells were collected and again expression of interest genes was evaluated.

MDM2 (P=0.028), MDM4 (P=0.028), USP7 (P=0.028), and HDAC1 (P=0.015) all showed significantly higher expression in EBNA1-harboring cells compared to control plasmid transfected cells, while p53 mRNA expression was only marginally downregulated in EBNA1 harboring cells (P=0.685). Four-day after treatment, none of the studied genes was significantly changed. Also, in the first 24-hour after treatment, mRNA expression of p53 was downregulated (P=0.685), but after 4 days it was upregulated (P=0.7) insignificantly.

It seems that EBNA1 could strongly upregulate p53-inhibiting genes including HDAC1, MDM2, MDM4, and USP7. Moreover, it appears that the effects of USP7 suppression on p53 at protein/mRNA level depend on the cell nature; however, further research is needed.

During research on lymphoma and its malignancies, scientists have traced the role of the angiogenesis index in patient survival. Epstein-Barr virus (EBV) is a human tumor-causing virus that targets B lymphocytes and causes persistent infection. This virus is also associated with malignancies, such as Burkitt's lymphoma. Using herbal medicines to treat cancer and angiogenesis has been considered, due to the side effects of chemical drugs. This experimentation aimed to research the antiviral impact of nano-curcumin on the Daudi cell line (which belongs to Burkitt's lymphoma) and to evaluate the expression of the vascular endothelial growth factor (VEGF) gene.

The cytotoxicity of nano curcumin, curcumin, and dendrosome on Daudi cells and normal human lymphocytes was evaluated using an MTT assay. Cellular apoptosis was assessed by Annexin / PI flow cytometry. The VEGF angiogenesis gene expression was performed by real-time PCR.

The 50% cytotoxic concentration (CC50) was determined 30 μg/ml for dendrosomal nano-curcumin, 50 μg/ml for curcumin, and 987 μg/ml for dendrosome in the Daudi cell line.Dendrosomal nano curcumin (DNC) caused time and dose-dependent death in Daudi cancer cells compared to curcumin. Dendrosome did not show toxicity on control cells. The results of Flow cytometry are constant with the results of the MTT test. The data obtained from the real-time PCR showed a significant decrease in the expression of the VEGF gene (P <0.01).

The dendrosomal nano curcumin is involved in angiogenesis by reducing the expression of the VEGF gene, and can be a good candidate as a supplement drug in the chemotherapy treatment of Burkitt's lymphoma.

The prevalence of breast cancer has increased and has currently become one of the most common cancers. Although the majority of the world’s population is infected with Epstein Barr Virus (EBV) during their lives, the severity of symptoms varies and not everyone infected with EBV is diagnosed with cancer. EBV might increase the risk for breast cancer either by activating the HER2/HER3 signaling cascades or by creating a state of prolonged immune stimulation.

A systematic search of several electronic databases including PubMed, ScienceDirect, Cochrane, EBSCOhost, JSTOR, and Scopus, following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines was conducted. The primary outcome of this review was to assess the prevalence of people with breast cancer that had a prior EBV infection.

For this review, 24 case-control studies were accepted. Our analyses included 1.989 breast cancer cases versus 1.034 control cases. EBV was found to be present in 27.9% of breast cancer cases versus 8.02% found in the normal breast tissue of controls. All affected people were women with a mean age was 48.19 years. The most common type of breast cancer found in EBV-infected tissues was invasive breast cancer. Cases were reported sporadically in a wide geographical distribution, and the prevalence varied from 4.6% - 64.1%.

A previous EBV infection might be associated with a higher risk for breast malignancy. The most common type is invasive cancer. It mainly affects women and geographical variances are observed. More studies are necessary to elucidate the role of EBV in the mechanisms of breast cancer. Also, it is crucial to improve the prevention and treatment strategies.

Environmental factors may play a role in colon cancer. In this view, several studies investigated tumor samples for the presence of various viral DNA with conflicting results. The purpose of this study is to investigate the prevalence of Human papillomaviruses (HPVs) and Epstein-Barr virus (EBV) in patients with colorectal carcinomas.

In this study, we collected 74 tumorous paraffin-embedded tissues (Mean±SD age: 66.3±14.98) from the Pathology Department of a hospital in AinTemouchent and laboratories of pathological anatomy in western Algeria. DNA from each tissue was extracted and the presence of HPV and EBV was investigated using PCR.

None of our samples were HPV or EBV positive, and we failed to find an obvious correlation between EBV and HPV infections and this type of cancer.

The results suggested that EBV and HPV infection is not common in patients with colorectal cancer in our population. However, the findings merit more investigations on a large number of cases.

Among the various factors involved in the development of gastric cancer (GC), infectious agents are one of the most important causative inducers. This study aimed to investigate the possible role of EBV gene expression on SHP1 methylation in co-infection with Helicobacter pylori in patients with GC.

Formalin-fixed paraffin-embedded samples were obtained from 150 patients with gastrointestinal disorders. The presence of the H. pylori and EBV genome were examined by PCR. The expression level of viral gene transcripts and methylation status of the SHP1 cellular gene was assessed by quantitative real-time PCR and methyl-specific PCR.

EBV and H. pylori coinfection were reported in 5.6% of patients. The mean DNA viral load was significant in patients coinfected with cagA-positive H. pylori (P= 0.02). The expression of BZLF1 and EBER was associated with GC. Also, the expression level of BZLF1in GC tissues was significantly higher in coinfection (P = 0.01). SHP1 methylation frequency was higher in the GC group than in the control group (P = 0.04). The correlation between the methylation rate and the H. pylori infection was highly significant (P<0.0001). The strongest positive correlation was observed in GC specimens between SHP1 methylation and H. pylori cagA-positive strains (p= 0.003).

Our results suggested that cagA might involve in the elevation of EBV lytic gene expression and SHP1 methylation, and the development of gastric cancer. Understanding the mechanism of EBV H. pylori - cagA + coinfection, as well as host epigenetic changes, can play an important role in diagnosing and preventing gastric cancer.

Among Human Immunodeficiency Virus (HIV)-infected individuals, Epstein-Barr virus (EBV) and Human Herpesvirus (HHV)-8 could cause significant illness as opportunistic infections. The purpose of the present study was to evaluate the prevalence of EBV and HHV-8 in saliva specimens obtained from HIV-1 infected Iranian individuals under the Highly Active Antiviral Therapy (HAART) regimen compared with naïve patients.

A cross-sectional study was conducted on 103 HIV-1 positive patients who attended the hospitals affiliated with the Iran University of Medical Sciences, in Tehran, Iran, from 2018 to 2019. Enzyme-linked immunosorbent assay (ELISA) test was performed to evaluate HHV-8 and EBV antibodies. A conventional polymerase chain reaction (PCR) was carried out on saliva samples to detect EBV infection and a nested-PCR assay for HHV-8 infection. SPSS (version 20) was used for statistical analysis.

Patients' mean age ± SD was 43.9 ± 16 (range 18-82 years), and from among 103 participants, 59 (57.3%) were male. The results of PCR showed that HHV-8 infection was found in 19 (18.4%), and EBV infection was found in 61 (59.2%) participants. Also, HHV-8 antibody was detected in 73 (70.9%), and EBV antibody in 97 (94.2%) patients. A significant association was observed between patients under treatment with HAART and HHV-8 DNA or EBV DNA infection in saliva.

HIV-infected patients demonstrated a remarkable rate of EBV and HHV-8 in saliva, which could have a great role in the shedding of viruses. Also, they may contribute to the establishment of further opportunistic infections and devastating complications.