Disparities in the Levels of Whole-Blood Epstein-Barr Virus between the Cancer and Non-Cancer Populations in Zhejiang,China

Objective This study aimed to investigate the prevalence of Epstein-Barr virus(EBV)infection in patients with and without cancer.Methods A total of 26,648 participants who underwent whole-blood EBV DNA(WBEBV)assays between January 1,2020,and August 31,2023,were included.The chi-square test was used for categorical data analysis,and R software was used to analyze the differences in EBV DNA load levels and the diagnostic capabilities of WBEBV.Results Positive rates were 10.2%and 25.4%for healthy controls(HC)and patients,respectively.The positivity rate for EBV-associated neoplasms(EN)was the highest at 7.53%,followed by leukemia(Le)at 5.49%.The subgroup analysis showed that the positivity rate for abnormal proliferation or hyperplasia(APH)was 31.9%,followed by 30.5%for Le.The WBEBV of patients with transplants(TP),especially living-related transplants(LT),was the highest among all subgroups.WBEBV at diagnosis was used to differentiate between infectious mononucleosis(IM)and chronic active Epstein-Barr virus(CAEBV),with a sensitivity of 67.4%(95%confidence interval[CI]:57.6-75.8)and specificity of 72%(95%CI:63.3-79.3).We conclude that the prevalence of EBV infection is low in the healthy population in this region and that a high EBV load at baseline is more common in LT,IM,and Lymphocyte Leukemia(LL).Conclusion This study used a large-sample survey to characterize the prevalence of whole-blood EBV levels in various diseases,including the stages and subtypes.The EBV detection rate was higher in patients with malignant disease than in those with benign disease.Our study provides clinicians with baseline information regarding EBV-associated diseases.

N6-methyladenosine methylation regulates the tumor microenvironment of Epstein-Barr virus-associated gastric cancer

BACKGROUND N6-methyladenosine(m6A)methylation modification exists in Epstein-Barr virus(EBV)primary infection,latency,and lytic reactivation.It also modifies EBV latent genes and lytic genes.EBV-associated gastric cancer(EBVaGC)is a distinctive molecular subtype of GC.We hypothesized EBV and m6A methylation regulators interact with each other in EBVaGC to differentiate it from other types of GC.AIM To investigate the mechanisms of m6A methylation regulators in EBVaGC to determine the differentiating factors from other types of GC.METHODS First,The Cancer Gene Atlas and Gene Expression Omnibus databases were used to analyze the expression pattern of m6A methylation regulators between EBVaGC and EBV-negative GC(EBVnGC).Second,we identified Gene Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)functional enrichment of m6A-related differentially expressed genes.We quantified the relative abundance of immune cells and inflammatory factors in the tumor microenvironment(TME).Finally,cell counting kit-8 cell proliferation test,transwell test,and flow cytometry were used to verify the effect of insulin-like growth factor binding protein 1(IGFBP1)in EBVaGC cell lines.RESULTS m6A methylation regulators were involved in the occurrence and development of EBVaGC.Compared with EBVnGC,the expression levels of m6A methylation regulators Wilms tumor 1-associated protein,RNA binding motif protein 15B,CBL proto-oncogene like 1,leucine rich pentatricopeptide repeat containing,heterogeneous nuclear ribonucleoprotein A2B1,IGFBP1,and insulin-like growth factor 2 binding protein 1 were significantly downregulated in EBVaGC(P<0.05).The overall survival rate of EBVaGC patients with a lower expression level of IGFBP1 was significantly higher(P=0.046).GO and KEGG functional enrichment analyses showed that the immunity pathways were significantly activated and rich in immune cell infiltration in EBVaGC.Compared with EBVnGC,the infiltration of activated CD4+T cells,activated CD8+T cells,monocytes,activated dendritic cells,and plasmacytoid dendritic cells were significantly upregulated in EBVaGC(P<0.001).In EBVaGC,the expression level of proinflammatory factors interleukin(IL)-17,IL-21,and interferon-γ and immunosuppressive factor IL-10 were significantly increased(P<0.05).In vitro experiments demonstrated that the expression level of IGFBP1 was significantly lower in an EBVaGC cell line(SNU719)than in an EBVnGC cell line(AGS)(P<0.05).IGFBP1 overexpression significantly attenuated proliferation and migration and promoted the apoptosis levels in SNU719.Interfering IGFBP1 significantly promoted proliferation and migration and attenuated the apoptosis levels in AGS.CONCLUSION m6A regulators could remodel the TME of EBVaGC,which is classified as an immune-inflamed phenotype and referred to as a“hot”tumor.Among these regulators,we demonstrated that IGFBP1 affected proliferation,migration,and apoptosis.

Evaluating the role of interleukin-2 and interleukin-12 in pediatric patients with concurrent Mycoplasma pneumoniae and Epstein-Barr virus infections

BACKGROUND Mycoplasma pneumoniae(MP)frequently causes respiratory infections in children,whereas Epstein-Barr virus(EBV)typically presents subclinical manifestations in immunocompetent pediatric populations.The incidence of MP and EBV coinfections is often overlooked clinically,with the contributory role of EBV in pulmonary infections alongside MP remaining unclear.AIM To evaluate the serum concentrations of interleukin-2(IL-2)and interleukin-12(IL-12)in pediatric patients with MP pneumonia co-infected with EBV and assess their prognostic implications.METHODS We retrospectively analyzed clinical data from patients diagnosed with MP and EBV co-infection,isolated MP infection,and a control group of healthy children,spanning from January 1,2018 to December 31,2021.Serum IL-2 and IL-12 levels were quantified using enzyme-linked immunosorbent assay.Logistic regression was employed to identify factors influencing poor prognosis,while receiver operating characteristic(ROC)curves evaluated the prognostic utility of serum IL-2 and IL-12 levels in co-infected patients.RESULTS The co-infection group exhibited elevated serum IL-2 and C-reactive protein(CRP)levels compared to both the MP-only and control groups,with a reverse trend observed for IL-12(P<0.05).In the poor prognosis cohort,elevated CRP and IL-2 levels,alongside prolonged fever duration,contrasted with reduced IL-12 levels(P<0.05).Logistic regression identified elevated IL-2 as an independent risk factor and high IL-12 as a protective factor for adverse outcomes(P<0.05).ROC analysis indicated that the area under the curves for IL-2,IL-12,and their combination in predicting poor prognosis were 0.815,0.895,and 0.915,respectively.CONCLUSION Elevated serum IL-2 and diminished IL-12 levels in pediatric patients with MP and EBV co-infection correlate with poorer prognosis,with combined IL-2 and IL-12 levels offering enhanced predictive accuracy.

Epstein-Barr virus positive post-transplant lymphoproliferative disorder with significantly decreased T-cell chimerism early after transplantation:A case report

BACKGROUND Post-transplant lymphoproliferative disorder(PTLD)is a rare but highly fatal complication occurring after allogeneic hematopoietic cell transplantation(allo-HCT)or solid organ transplantation(SOT).Unlike SOT,PTLD after allo-HCT usually originates from the donor and is rarely accompanied by a loss of donor chimerism.CASE SUMMARY We report a case of Epstein-Barr virus positive PTLD manifesting as diffuse large B-cell lymphoma(DLBCL)with significantly decreased T-cell chimerism early after allo-HCT.A 30-year-old patient with acute myeloid leukemia underwent unrelated allo-HCT after first complete remission.Nearly 3 mo after transplantation,the patient developed cervical lymph node enlargement and gastric lesions,both of which were pathologically suggestive of DLBCL.Meanwhile,the patient experienced a significant and persistent decrease in T-cell chimerism.A partial remission was achieved after chemotherapy with single agent rituximab and subsequent R-CHOP combined chemotherapy.CONCLUSION The loss of T-cell chimerism and the concomitant T-cell insufficiency may be the cause of PTLD in this patient.

Research Advances in Infectious Mononucleosis Caused by Epstein-Barr Virus

Infectious mononucleosis (IM), primarily caused by the Epstein-Barr virus (EBV), manifests as the classic triad of fever, pharyngitis, and cervical lymphadenopathy. Severe cases may involve organ damage, most commonly affecting the liver. Diagnosis relies on a combination of clinical presentation and laboratory parameters, with commonly used indicators including EBV-specific antibodies, EBV-DNA load, and the ratio of atypical lymphocytes. Treatment primarily involves symptomatic supportive care, with a cautious approach to the routine use of antiviral medications. In recent years, significant research in traditional Chinese medicine has been conducted in China, showing promising advancements. This article provides a comprehensive review of EBV-induced infectious mononucleosis, offering insights for clinical diagnosis and treatment.

Positive correlation between latent Epstein-Barr virus infection and severity of illness in inflammatory bowel disease patients

BACKGROUND Emerging studies indicate the critical involvement of microorganisms,such as Epstein-Barr virus(EBV),in the pathogenesis of inflammatory bowel disease(IBD).Immunosuppressive therapies for IBD can reactivate latent EBV,complicating the clinical course of IBD.Moreover,the clinical significance of EBV expression in B lymphocytes derived from IBD patients’intestinal tissues has not been explored in detail.AIM To explore the clinical significance of latent EBV infection in IBD patients.METHODS Latent EBV infection was determined by double staining for EBV encoded RNA and CD20 in colon specimens of 43 IBD patients who underwent bowel resection.Based on the staining results,the patients were divided into two groups,according to their latent EBV infection states-negative(n=33)and positive(n=10).Illness severity of IBD were assigned according to Crohn’s disease activity index(ulcerative colitis)and Mayo staging system(Crohn’s disease).The clinicpathological data were analyzed between the two different latent EBV groups and also between the mild-to-moderate and severe disease groups.RESULTS Systolic pressure(P=0.005),variety of disease(P=0.005),the severity of illness(P=0.002),and pre-op corticosteroids(P=0.025)were significantly different between the EBV-negative and EBV-positive groups.Systolic pressure(P=0.001),variety of disease(P=0.000),pre-op corticosteroids(P=0.011)and EBV infection(P=0.003)were significantly different between the mild-to-moderate and severe disease groups.CONCLUSION IBD patients with latent EBV infection may manifest more severe illnesses.It is suggested that the role of EBV in IBD development should be further investigated,latent EBV infection in patients with serious IBD should be closely monitored,and therapeutic course should be optimized.

Epstein-Barr virus-induced infection-associated hemophagocytic lymphohistiocytosis with acute liver injury:A case report

BACKGROUND Hemophagocytic lymphohistiocytosis(HLH)is a severe hyperinflammatory reaction,which is rare and life-threatening.According to the pathogen,HLH is divided into genetic and acquired.The most common form of acquired HLH is infection-associated HLH,of which Herpes viruses,particularly Epstein-Barr virus(EBV),are the leading infectious triggers.However,it is difficult to distinguish between simple infection with EBV and EBV-induced infectionassociated HLH since both can destroy the whole-body system,particularly the liver,thereby increasing the difficulty of diagnosis and treatment.CASE SUMMARY This paper elaborates a case about EBV-induced infection-associated HLH and acute liver injury,aiming to propose clinical guides for the early detection and treatment of patients with EBV-induced infection-associated HLH.The patient was categorized as acquired hemophagocytic syndrome in adults.After the ganciclovir antiviral treatment combined with meropenem antibacterial therapy and methylprednisolone inhibition to inflammatory response,gamma globulin enhanced immunotherapy,the patient recovered.CONCLUSION From the diagnosis and treatment of this patient,attention should be paid to routine EBV detection and a further comprehensive understanding of the disease as well as early recognition and early initiation are keys to patients’survival.

Epstein-Barr virus:Silent companion or causative agent of chronic liver disease?

The Epstein-Barr virus(EBV)has an important and multifaceted role in liver pathology.As a member of the herpes virus family,EBV establishes a persistent infection in more than 90%of adults.Besides acute hepatitis during primary infection,many clinical syndromes of interest for the hepatologist are associated with EBV infection.The role of EBV in the evolution of chronic hepatitis from hepatotropic viruses is considered.Chronic EBVassociated hepatitis is suspected in immunocompetent adults with compatible serology,suggestive histology and detection of the viral genome in the liver and/or increase of specific circulating cytotoxic T-lymphocytes.EBV is the main cause of post-transplant lymphoproliferative disorders which occur in up to 30%of cases.EBV-driven lymphoproliferative diseases are also recognized in non-immunocompromised patients and liver is involved in up to a third of the cases.Directly implicated in the pathogenesis of different tumors,EBV has a disputable role in hepatocellular carcinoma carcinogenesis.Further research is required in order to establish or reject the role of EBV in human liver cancer.This paper attempts to discuss the range of EBV-associated chronic liver diseases in immunocompetent patients,from mild,self-limiting mononuclear hepatitis to liver cancer.

Clinical and pathological characterization of epstein-barr virus-associated gastric carcinomas in portugal

AIM To determine the prevalence of epstein-barr virus(eb V)-associated gastric carcinomas in the North Region of Portugal and to study its clinicopathological characteristics. METHODS We have performed a retrospective study including a total of 179 consecutive patients with gastric cancer(GC) submitted to gastrectomy during 2011 at the Portuguese Oncology Institute of Porto. Clinical and pathological data was collected from individual clinical records and inserted on a database with unique codification. Tumour tissues were collected from the institutional tumour bank. eb V was detected by in situ hybridization for the detection of eb V-encoded small RNAs(ebe Rs) and eb V latent proteins(LMP1 and LMP2 A) were detected by immunohistochemistry.RESULTS The analysis showed that eb V-associated gastric carcinomas(eb Va GC) represents 8.4%(15/179) of all GC cases, with a significant differential distribution among histological types(P < 0.001): 100%(3/3) of medullary carcinomas, 100%(1/1) of adenosquamous carcinoma, 8.7%(8/92) of tubular adenocarcinomas, 8.0%(2/25) of mixed carcinomas and 2%(1/51) in poorly cohesive carcinomas. The analysis revealed a higher predominance of eb Va GC in the upper third and middle(cardia, fundus and body) of the stomach(P = 0.041), a significant lower number of regional lymph nodes invasion(P = 0.025) and a tendency for better prognosis(P = 0.222). eb V latent protein expression revealed that all eb Va GC cases were LMP1-negative, nevertheless 6 cases(40%) expressed LPM2 A, which reveals that these cases show a distinct eb V-Latency profile(latency II-like).CONCLUSION eb Va GC represents 8.4% of all GC in the North Region of Portugal. The eb V-infected patients have specific clinic-pathological features that should be further explored to develop new strategies of management and treatment.

Development of Epstein-Barr virus-associated gastric cancer:Infection,inflammation,and oncogenesis

Epstein-Barr virus(EBV)-associated gastric cancer(EBVaGC)cells originate from a single-cell clone infected with EBV.However,more than 95%of patients with gastric cancer have a history of Helicobacter pylori(H.pylori)infection,and H.pylori is a major causative agent of gastric cancer.Therefore,it has long been argued that H.pylori infection may affect the development of EBVaGC,a subtype of gastric cancer.Atrophic gastrointestinal inflammation,a symptom of H.pylori infection,is observed in the gastric mucosa of EBVaGC.Therefore,it remains unclear whether H.pylori infection is a cofactor for gastric carcinogenesis caused by EBV infection or whether H.pylori and EBV infections act independently on gastric cancer formation.It has been reported that EBV infection assists in the oncogenesis of gastric cancer caused by H.pylori infection.In contrast,several studies have reported that H.pylori infection accelerates tumorigenesis initiated by EBV infection.By reviewing both clinical epidemiological and experimental data,we reorganized the role of H.pylori and EBV infections in gastric cancer formation.

Epstein-Barr virus-associated smooth muscle tumors in immunocompromised patients:Six case reports

BACKGROUND Epstein-Barr virus associated smooth muscle tumor(EBV-SMT)is a rare oncological entity.However,there is an increasing incidence of EBV-SMTs,as the frequency of organ transplantation and immunosuppression grows.EBV-SMT diagnosis relies on histopathology and immunochemical staining to distinguish it from post-transplant lymphoproliferative disorder(PTLD).There is no clear consensus on the treatment of EBV-SMTs.However,surgical resection,chemotherapy,radiation therapy,and immunosuppression reduction have been explored with varying degrees of success.CASE SUMMARY Our case series includes six cases of EBV-SMTs across different age groups,with different treatment modalities,adding to the limited existing literature on this rare tumor.The median latency time between immunosuppression and disease diagnosis is four years.EBV-SMTs present with variable degrees of aggressiveness and seem to have worse clinical outcomes in patients with tumor multiplicity and worse immunocompetency.CONCLUSION It is imperative to continue building on this knowledge and keeping EBV-SMTs on the differential in immunocompromised individuals.

Heterochronic triple primary malignancies with Epstein-Barr virus infection and tumor protein 53 gene mutation:A case report and review of literature

BACKGROUND The diagnosis and etiology of multiple primary malignant neoplasms(MPMNs)are difficult to establish.Here,we report a case of heterochronic triple primary malignancies with gastric cancer,nasopharyngeal squamous cell cancer,and then rectal cancer.CASE SUMMARY The patient was first diagnosed with gastric cancer at the age of 33 in 2014 and underwent distal gastrectomy and gastrojejunostomy and six cycles of adjuvant chemotherapy.Three years later,he was diagnosed with nasopharyngeal cancer and treated with radical chemoradiotherapy in 2017.Recently,a mass in the middle of the rectum was resected and reported as ulcerative,moderately to poorly differentiated adenocarcinoma.Research on the etiology of MPMNs showed that Epstein-Barr virus(EBV)infection may be the cause of gastric cancer and nasopharyngeal squamous cell cancer since these two primary lesions were positive for transcripts of EBV-encoded ribonucleic acid using an in situ hybridization EBV-encoded ribonucleic acid probe in formalin-fixed,paraffinembedded tissue.The cause of rectal cancer may be due to a somatic mutation of tumor protein 53 gene in exon 8(c.844C>T,p.Arg282Trp)through highthroughput sequencing for the rectal cancer.Appropriate standard therapy for each primary cancer was administered,and the patient has no evidence of cancer disease to date.CONCLUSION To our knowledge,this is the first report on heterochronic triple primary malignancies whose cause may be associated with EBV infection and tumor protein 53 genetic mutations.The etiological research may not only elucidate the cause of MPMN but also has implications in clinical management.

Epstein-Barr virus-encoded small RNAs in idiopathic orbital inflammatory pseudotumor tissues: a comparative case series

AIM： To investigate the positive rate and types of cells that express Epstein-Barr virus-encoded small RNAs （EBERs） and to determine the distribution of EBER-expressing cells in idiopathic orbital inflammatory pseudotumor （IOIP） tissues. METHODS： We retrospectively examined 40 archived paraffin specimens from two teaching hospitals in Southern China between January 2007 and January 2015 that were pathologically determined to exhibit IOIP. Eleven concurrent paraffin specimens of thyroid-associated ophthalmopathy （TAO） composed the control group. In situ hybridization was performed to detect EBERs. Immunohistochemistry was employed to detect CD3, CD20, Vimentin, and smooth muscle actin （SMA）, and the positive rate, types of positive cells, and distribution and location of EBERs were evaluated. RESULTS： The positive expression rate of EBERs was 47.5% （19/40） in the IOIP group, which was significantly higher than that in the TAO group [0 （0/11）, P=-0.011]. in the IOIP group, the lymphocyte infiltrative subtype, fibrotic subtype, and mixed subtype exhibited EBER-positive rates of 57.1% （12121）, 12.5% （118）, and 54.5% （6/11）, respectively, and no significant differences were found between these subtypes （P=0.085）. Positive signals of EBERs were mainly present in medium-small lymphocytes between or around follicles and in the nuclei of activated immunoblasts （14/19）. CONCLUSION： The positive rate, types, and distribution of EBER-expressing cells in IOIP have been documented.These findings are conducive for a better understanding of the underlying mechanisms of Epstein-Barr virus infection in IOIP pathogenesis.

Epstein-Barr virus-associated gastric carcinoma: Evidence of age-dependence among a Mexican population

AIM： To investigate features of Epstein-Barr virus （EBV）associated gastric carcinoma （EBVaGC） among a Mexican population. METHODS： Cases of primary gastric adenocarcinoma were retrieved from the files of the Departments of Pathology at the Instituto Nacional de Cancerologia and the Instituto Nacional de la Nutrición in Mexico City. The anatomic site of the gastric neoplasia was identified, and carcinomas were histologically classified as intestinal and diffuse types and subclassified as proposed by the Japanese Research Society for Gastric Cancer. EBV-encoded small non-polyadenylated RNA-1 （EBER-1） in situ hybridization was conducted to determine the presence of EBV in neoplastic cells. RESULTS： We studied 330 consecutive, non-selected, primary gastric carcinomas. Among these, there were 173 male and 157 female patients （male/female ratio 1.1/1）. EBER-1 was detected in 24 （7.3%） cases （male/ female ratio： 1.2/1）. The mean age for the entire group was 58.1 years （range： 20-88 years）, whereas the mean age for patients harboring EBER-1-positive gastric carcinomas was 65.3 years （range： 50-84 years）. Age and histological type showed statistically significant differences, when EBER-1-positive and -negative gastric carcinomas were compared. EBER-1 was detected in hyperplastic- and dysplastic-gastric mucosa surrounding two EBER-1-negative carcinomas, respectively. CONCLUSION： Among Latin-American countries, Mexico has the lowest frequency of EBVaGC. Indeed, the Mexican population 〉50 years of age was selectively affected. Ethnic variations are responsible for the epidemiologic behavior of EBVaGC among the worldwide population.

Correlation of Epstein-Barr virus and its encoded proteins with Helicobacter pylori and expression of c-met and c-myc in gastric carcinoma

AIM： To investigate the interrelationship of Epstein-Barr virus （EBV） and EBV- encoded proteins with Helicobacter pylori （H pylor/~ infection and the expression of c-met and c-myc oncogene proteins in gastric carcinoma, and to explore their role in gastric carcinogenesis. METHODS： One hundred and eighty-five gastric carcinoma tissues were detected by polymerase chain reaction （PCR）-Southern blot for EBV genome and in situ hybridization （ISH） for EBV-encoded small RNA 1 （EBER1）. Gastric carcinoma with positive EBER1 signals was confirmed EBV-associated gastric carcinoma （EBVaGC）. The status of Hpylori infection in 185 gastric carcinomas was assessed by rapid urease test and PCR. The samples with positive PCR and urease test were defined as H pylorl infection. The expression of c-met and c-myc oncogene proteins in tissues of EBVaGC and matched EBV-negative gastric carcinoma （EBVnGC） were examined by immunohistochemistry. RT-PCR and Southern hybridization were used to detect the expression of nuclear antigens （EBNAs） 1 and 2, latent membrane protein （LMP） 1, early genes BARF1 and BHRF1 in EBVaGC cases. RESULTS： The positive rate of H pylori and EBV in 185 gastric carcinomas was 59.45% （110/185） and 7.03% （13/185） respectively. No difference was found in sex, age, pathological differentiation, clinical stages and lymph node metastasis between H pylori-positive and H pylori-negative gastric carcinomas. However, the positive rate of H pylori infection in the antrum gastric carcinomas was higher than that of cardia and body gastric carcinomas. In our series, age, pathological differentiation, clinical stages, lymph node metastasis and location of cancer were not different between EBVnGC and EBVaGC, while the positive rate of EBV in male patients was significantly higher than that of female patients. The positivity of Hpylori in EBV-associated and EBV-negative gastric carcinomas was 46.15% （6/13） and 81.40%（104/172） respectively. There was no significant correlation between EBV and H pylori infection. The c-met overexpression was significantly higher in the EBVaGC group than in the EBVnGC group. However, c-met and c-myc expression did not show significant difference between the two groups. Transcripts of EBNA1 were detected in all 13 EBVaGCs, while both EBNA2 and LMP1 mRNA were not detected. Six of the 13 cases exhibited BARF1 transcripts and 2 exhibited BHRF1 transcripts. CONCLUSION： The positivity of H pylori in EBVnGCs is higher than that of EBVaGCs, but no significant correlation is found between EBV infection and H pylori infection. H pylori-positive gastric carcinoma is predominant in antrum location, while EBVaGC has a tendency of predominance in cardia/body location. EBV infection is associated with c-met abnormal expression but not with c-myc protein in EBVaGC. c-met overexpression is not induced by LMP1. BARF1 and BHRF1 may play important roles in the tumorigenesis of EBVaGC through different pathways.

Relationship between Epstein-Barr virus-encoded proteins with cell proliferation,apoptosis,and apoptosis-related proteins in gastric carcinoma

AIM: To investigate the interrelationship between Epstein-Barr virus (EBV)-encoded proteins and cell proliferation, apoptosis and apoptosis-related proteins in gastric carcinoma, and to explore their role in gastric carcinogenesis. METHODS: Tissues from 13 cases of EBV-associated gastric carcinoma (EBVaGC) and 45 cases of matched EBV-negative gastric carcinoma (EBVnGC) were collected, and then subjected to analysis for apoptotic index (AI) using the terminal deoxynucleotidyl transferase (TdT)-mediated dUTP-biotin nick end-labeling (TUNEL) assay. Nuclear cell proliferation-associated antigen ki-67 index (KI), bcl-2, and p53 expression were examined by immunohistochemistry.p53 mutation in exons 5-8 of 13 EBVaGC cases was determined by single-strand conformation polymorphism (SSCP) and DNA sequencing.RT-PCR and Southern hybridization were used to detect the expression of nuclear antigens (EBNAs) 1 and 2, latent membrane protein (IMP) 1, immediately early gene BZLF1 and early genes BARF1 and BHRF1 in 13 EBVaGC cases. RESULTS: The percentage of AI, KI and p53 overexpression was significantly lower in the EBVaGC group than in the EBVnGC group. However, bcl-2 expression did not show significant difference between the two groups. p53 gene mutations were not found in 13 EBVaGCs. Transcripts of EBNA1 were detected in all 13 EBVaGCs, while both EBNA2 and LMP1 mRNA were not detected. Six of the thirteen cases exhibited BZLF1 transcripts and two exhibited BHRF1 transcripts. BARF1 mRNA was detected in six cases. CONCLUSION: Lower AI and KI may reflect a low biological activity in EBVaGC. EBV infection is associated with p53 abnormal expression but not bcl-2 protein in EBVaGC. BZLF1,BARF1,and BHRF1 may play important roles in inhibiting cell apoptosis and tumorigenesis of EBVaGC through different pathways.

DNA methylation in gastric cancer, related to Helicobacter pylori and Epstein-Barr virus

Gastric cancer is a leading cause of cancer death worldwide,and significant effort has been focused on clarifying the pathology of gastric cancer.In particular,the development of genome-wide analysis tools has enabled the detection of genetic and epigenetic alterations in gastric cancer;for example,aberrant DNA methylation in gene promoter regions is thought to play a crucial role in gastric carcinogenesis.The etiological viewpoint is also essential for the study of gastric cancers,and two distinct pathogens,Helicobacter pylori(H.pylori)and Epstein-Barr virus(EBV),are known to participate in gastric carcinogenesis.Chronic inflammation of the gastric epithelium due to H.pylori infection induces aberrant polyclonal methylation that may lead to an increased risk of gastric cancer.In addition,EBV infection is known to cause extensive methylation,and EBV-positive gastric cancers display a high methylation epigenotype,in which aberrant methylation extends to not only Polycomb repressive complex(PRC)-target genes in embryonic stem cells but also non-PRC-target genes.Here,we review aberrant DNA methylation in gastric cancer and the association between methylation and infection with H.pylori and EBV.

Epigenetic dysregulation in Epstein-Barr virus-associated gastric carcinoma: Disease and treatments

Epstein-Barr virus(EBV)-associated gastric carcinoma(EBVaGC)comprises nearly 10%of gastric carcinoma cases worldwide.Recently,it was recognised to have unique clinicopathologic characteristics,including male predominance,lower rates of lymph node involvement,and better prognosis.EBVaGC is further characterised by abnormal hypermethylation of tumour suppressor gene promoter regions,causing down-regulation of their expression.In the present review,we critically discuss the role of EBV in gastric carcinogenesis,summarising the role of viral proteins and microRNAs with respect to aberrant methylation in EBVaGC.Given the role of epigenetic dysregulation in tumourigenesis,epigenetic modifiers may represent a novel therapeutic strategy.

Expression of Epstein-Barr virus genes in EBV-associated gastric carcinomas

AIM: To understand the expression of latent and lytic genes of Epstein-Barr virus (EBV) in EBV-associated gastric carcinoma (EBVaGC) and to explore the relationship between EBV-encoded genes and development of EBVaGC at molecular level, METHODS: One hundred and seventy-two gastric carcinoma tissues and 172 corresponding para-carcinoma tissues were tested for EBV genome by polymerase chain reaction (PCR)-Southern blotting. EBV-encoded small RNA (EBER) 1 of the PCR positive specimens was detected by in situ hybridization (ISH). Gastric carcinomas with positive EBER1 signals were classified as EBVaGCs. RT-PCR and Southern hybridization were applied to the detection of expression of nuclear antigen (EBNA) promoters (Qp, Wp and Cp), EBNA 1 and EBNA 2, latent membrane proteins (LMP) 1, 2A and 2B and lytic genes (immediate early genes BZLF1 and BRLF1, early genes BARF1 and BHRF1, late genes BcLF1 and BLLF1) in EBVaGCs. RESULTS: Eleven EBV positive samples existed in gastric carcinoma tissues (6.39%). No EBV positive sample was found in corresponding para-carcinoma tissues. The difference between EBV positivity in carcinoma tissues and corresponding para-carcinoma tissues was significant (x2 = 9.0909, P = 0.0026). Transcripts of Qp and EBNA1 were detected in all the 11 EBVaGCs, while both Wp and Cp were silent. EBNA2, LMP1 and LMP2B mRNA were absent in all the cases, while LMP2A mRNA was detected in 4 of the 11 cases. Of the 11 EBVaGCs, 7 exhibited BcLFl transcripts and 2 exhibited BHRF1 transcripts. The transcripts of BZLF1 and BARF1 were detected in 5 cases, respectively. No BLLF1 and BRLF mRNA were detected. CONCLUSION: The latent pattern of EBV in gastric carcinoma corresponds to the latency I/II. Some lytic infection genes are expressed in EBVaGCs tissues. BARF1 and BHRF1 genes may play an important role in tumorigenesis of gastric carcinoma.

H pylori (CagA) and Epstein-Barr virus infection in gastric carcinomas:Correlation with p53 mutation and c-Myc,Bcl-2 and Bax expression

AIM: To investigate the interrelationship between H pylori and Epstein-Barr virus (EBV) infection in the gastric carcinogenesis having in focus the p53 mutation and the c-Myc, Bcl-2 and Bax expression. METHODS: seventy-one gastric carcinoma tissues were assessed by polymerase chain reaction (PCR) for H pylori and in situ hybridization for EBV. c-Myc, Bcl-2 and Bax expression were detected by immunohistochemistry and single-stranded conformational polymorphism (SSCP) for p53 mutation. RESULTS: The positivity rates for H pylori and EBV were 94.4% and 8.45%, respectively. The majority of the cases displayed only the H pylori presence. All EBV positive cases were also H pylori positive. None infectious agent was observed in 5.55% of the cases. The intestinal type tumor was more frequent in the co-infected and non-infected groups. The female predominated in the non-infected group showing statistical significance (70.4% vs 29.6%, P=0.039). The Bcl-2 was only detected in the group exclusively infected by H pylori. However, c-Myc and Bax were detected in the three groups but with a low frequency in the co-infected group. Mutation of p53 was present in all groups, with the highest frequencies in the H pylori positive groups. CONCLUSION: The frequency of H pylori infection in gastric carcinomas was high. The presented data indicated that gastric carcinogenesis has different pathways depending of the presence of the two investigated infectious agents, suggesting a possible involvement of H pylori with apoptotic process. The low expression of c-Myc and Bax in the EBV-positive groups suggests that EBV may inhibit the expression of these proteins. Nevertheless, p53 mutation shows to be a relevant alteration, independent of both infectious agents.