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.

Mucocutaneous ulcer positive for Epstein–Barr virus,misdiagnosed as a small bowel adenocarcinoma:A case report

BACKGROUND Epstein–Barr virus(EBV)-positive mucocutaneous ulcers(MCUs)are an uncommon disorder characterized by ulcerative lesions in the skin,oral cavity or gastrointestinal tract in patients with iatrogenic or aging-induced immunosuppression.The nonspecific lesions are difficult to differentiate from small bowel adenocarcinomas.We present the case of a 69-year-old woman who was initially misdiagnosed with a small bowel adenocarcinoma but was later surgically diagnosed with and treated for EBV-MCU.Through this case,we aim to emphasize the importance of accurately distinguishing between the two conditions.CASE SUMMARY The patient presented with an incidental finding of a small bowel tumor during computed tomography(CT)examination performed for hematuria.The CT scan showed irregular thickening of the distal ileum,which was suggestive of a malignant small bowel tumor.An exploratory laparotomy revealed an 8-cm mass in the distal ileum;thus,a segment of the small intestine,including the mass,was resected.Histopathological analysis revealed an ulceroinfiltrative mass-like lesion with luminal narrowing,marked inflammatory cell infiltration,and large atypical lymphoid cells(positive for EBV-encoded small RNA).A final diagnosis of an EBV-MCU was established.The postoperative course was uneventful,and the patient was discharged on postoperative day 7.The patient remained recurrencefree until 12 mo after surgery.CONCLUSION This case highlights the diagnostic challenges for EBV-MCUs and emphasizes the importance of comprehensive evaluation and accurate histopathological analysis.

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 EBER1signals 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 BZLF1and BRLF1, early genes BARF1 and BHRF1, late genes BcLF1and 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 EBNA1were 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 BcLF1 transcripts and 2 exhibited BHRF1 transcripts. The transcripts of BZLF1and BARF1 were detected in 5 cases, respectively. No BLLF1and BRLF mRNA were detected.CONCLUSION: The latent pattern of EBV in gastric carcinoma corresponds to the latency Ⅰ/Ⅱ. Some lyric infection genes are expressed in EBVaGCs tissues. BARF1 and BHRF1genes may play an important role in tumorigenesis of gastric carcinoma.

CHARACTERIZATION OF A HUMAN HERPES VIRUS－6（HHV－6） AND EPSTEIN－BARR VIRUS（EBV） ASSOCIATED LEUKEMIC CELL LINE，J6－1

This report characterizes the J6-1 cell line derived from a Chinese acute myelomonocytic leukemia patient and previously reported to be associated with EBV. These studies showed that J6-1 cells were also infected with HHV-6 as demonstrate at the DNA level by PCR and Southern blot hybridization and by expression of HHV-6 early membrane antigen on the J6-1 cell surface. Further characterization showed J6-1 was co-infected with EBV type 2. Generally, cells infected with EBV type 2 do not grow well in vitro. However, J6-1 , although difficult to maintain in vitro, has been grown for 15 years. Possibly, co-infection with HHV6 confers this property. In this regard, J6-1 cells exhibited density dependent growth which could be inhibited with an anti-HHV-6-MA monoclonal antibody(MAb). In contrast, anti-HHV-6-VCA MAb stimulated the J6-1 cell proliferation. Electron microscopic analysis showed that, morphologically, there were two types of J6-1 cell, one with lymphoblastoid features and one with a monocytoid appearance. Accordingly, the flow profile of the J6-1 cell line showed heterogeneity. with two populations comprised of CD15-, CD19+ cells with low light scatter(small cells) and a population with greater light scatter(larger cells) which was CD15+ , CD19+. The population was negative for progenitor cell markers(CD33, 34 ), and T cell markers. Southern analysis showed no T cell receptor rearrangement, however there was a clonal JH and kappa light chain expressing population. Glycocytochemical analysis showed several endogenous lectin receptors on the J6-1 cell surface: BSA-Xylose, BSA-Rhamnose, BSAGal. BSA-Lac. This cell line shares many characteristics with other monocytic/ lymphoblastoid cell lines isolated elsewhere and provides circumstantial evidence linking Herpes viruses, as least as co- factors,to leukemia cell growth.

STUDIES ON THE RELATIONSHIP BETWEEN EPSTEIN BARR VIRUS (EBV) AND PATHOGENESIS OF MULTIPLE MYELOMA

In order to explore the relationship between Epstein Barr virus (EBV) and pathogenesis of multiple myeloma (MM), the presence of EBV DNA in mononuclear cells of bone marrow (BMMC) and peripheral blood (PBMC) taken from 23 multiple myeloma patients who were neither posttransplanted nor HIV positive were examined by polymerase chain reaction (PCR). Meanwhile the presence of EBV EBERs in bioptic bone marrow's specimens of 4 MM patients were examined by in situ hybridization (ISH). Acute leukemia, aplastic anemia and malnourished anemia patients were taken as control. It showed EBV DNA detective rate in BMMC (69 6%) and in PBMC (39 1%) of MM patients were higher significantly than control groups (P<0 05). The positive signals of EBERs were located in BMMC and the EBV positive samples detected by ISH were consistent with those by PCR. The results indicate that EBV is closely correlated to pathogenesis of MM.

SERO-EPIDEMIOLOGICAL STUDIES OF EPSTEIN-BARR VIRUS(EBV) INFECTION BY TESTING ANTIBODIES AGAINST EBV SPECIFIC DNASE(EDAb) AS A METHOD FOR EARLY DETECTION OF NASOPHARYNGEAL CARCINOMA(NPC)

In 1987, a mass survey of EDAb was carried out in Sihui county of Gunagdong Province (the highest incidence area of NPC in China) and the city of Guangzhou using the methods previously established by our lab. In order to study the correlation between EDAb level and NPC, the titre of DEAb and their distribution in sera from 430 patients with NPC and 5030 normal persons were detected. It was found that the AER (level of EDAb was represented by the anti enzyme rate) of NPC patients gave a negative skew distribution and the Md=65.3% while the natural population (30 59 years old) gave a serious positive skew distribution and the Md is 7.9%. According to the pattern of EDAb distribution curve of 430 NPC patients and 2060 natural population. AER≥30% was defined as a cut off point between EDAb positive and negative. Using this value we got a rate of 90.7% (390/430) positive diagnosis in NPC patients, while in natural population the positive rate was 3.3% (68/2060), and in the IgA/VCA positive (1:5) normal person the positive rate was 6.0% (41/681). As to the other tumors including head and neck tumors the positive rate was 3.4% (7/204), similar to the natural population. After a period of 62 months of follow up surveillance, 15 of 224 EDAb positive normal persons found in the mass survey were diagnosed as NPC by histopathological examination. While in 4806 EDAb negative normal person only one case NPC patient was found in this period. 60% of these patients were diag nosed in their early stage of NPC. From these patients it was found that EDAb could appear in the sera of the patients as early as 62 months before NPC was definitely diagnosed. 2 of these patients were shown IgA/VCA negative and EDAb positive in mass survey. This suggested that in some of the precancerous patients EDAb could appear earlier than IgA/VCA. The signifi cance of the sera EDAb positivity of normal person was discussed.

A Case Report of Pediatric Epstein Barr Virus (EBV) Related Cholestasis from Al-Adan Hospital, Kuwait

Infectious mononucleosis is an acute illness due to Epstein Barr virus infection, which occurs commonly in young adults. Liver involvement in acute EBV infection occurs in up to 95% of patients between the 6th and 15th day of illness and is usually mild [1]. Here we report on a 7-year-old girl treated by Gastroenterology, Hepatology, and Nutrition Unit of Al-Adan Hospital pediatric Department, presented with prolonged fever, lymphadenopathy, generalized edema, hyperbilurubi- nemia and elevated liver enzymes secondary to EBV infection. This case represents a rare presentation of common viral infection in pediatric population.

Chronic Physical Stress Does Not Interact with Epstein-Barr Virus (EBV)-Encoded Dutpase to Alter the Sickness Response

Most adult humans have been infected with Epstein-Barr virus (EBV), which is thought to contribute to the development of chronic fatigue syndrome. Stress is known to influence the immune system and can exacerbate the sickness response. Although a role for psychological stress in the sickness response, particularly in combination with EBV-encoded deoxyuridine triphosphate nucleotidohydrolase (dUTPase) has been established, and the role of physical stressors in these interactions remains unspecified. In this study, we seek to determine the interaction of chronic physical (swim) stress and EBV-encoded dUTPase injection. We hypothesize that a chronic physical stressor will exacerbate the sickness response following EBV-encoded dUTPase injection. To test this hypothesis mice receive daily injections of EBV-encoded dUTPase or vehicle and are subjected to 15 min of swim stress each day for 14 days or left unmanipulated. On the final evening of injections mice undergo behavioral testing. EBV-encoded dUTPase injection alone produces some sickness behaviors. The physical swimming stress does not alter the sickness response.

Restraint Induces Sickness Responses Independent of Injection with Epstein-Barr Virus (EBV)-Encoded dUTPase

Most adult humans have been infected by Epstein-Barr virus (EBV), a putative cause of chronic fatigue syndrome, and carry latent EBV. The EBV-encoded dUTPase can induce sickness responses in mice and chronic stress exacerbates this response. Because individuals often adapt to chronic stress, we tested the hypothesis that acute restraint stress would potentiate these sickness responses elicited by EBV-encoded dUTPase. Male CD-1 mice were injected daily for one or three days with either saline or EBV-encoded dUTPase. Additionally, mice from each condition were either restrained for three hours daily or left undisturbed during the light phase when mice are inactive. Restraint decreased weight gain during the one- and three-day experiments. Restraint in saline injected mice increased anxiety-like behavior in the open field during the three-day experiment. There were no behavioral differences during the one-day experiment. Restraint stress had no effect when experienced acutely on one day, but did produce a sickness response after three days of exposure regardless of saline or dUTPase injection. In contrast to the effects of chronic stress and EBV-encoded dUTPase on the sickness response, acute stress did not affect sickness responses in association with EBV-encoded dUTPase. Thus, dUTPase does not appear to provoke the same sickness responses after acute stress as compared to chronic stress.

Epstein-Barr病毒相关淋巴上皮瘤样肝内胆管癌3例并文献复习

肝淋巴上皮瘤样癌(Lymphoepithelioma-like carcinoma,LELC)是一种极其罕见的恶性肿瘤,其特点是未分化的恶性上皮细胞及明显的淋巴浸润。肝LELC主要包括淋巴上皮瘤样肝细胞癌(lymphoepithelioma-like hepatocellularcarcinoma,LEL-HCC)和淋巴上皮瘤样肝内胆管癌(lymphoepithelioma-likeintrahepatic cholangiocarcinoma,LEL-CC)。EB病毒(Epstein-Barr virus,EBV)感染被认为是LELC癌变的重要因素。中南大学湘雅医院自2005年以来共收治3例EBV相关LEL-CC患者,CT均提示肝脏肿块,经手术切除后,3例患者EBV编码的RNA(EBV-encoded RNA,EBER)和CK19表达均为阳性,病理学证实为EBV相关的LEL-CC。2例患者术后预后良好,1例患者术后接受相关免疫治疗及化学治疗。结合现有文献分析,笔者认为可将肝LELC纳入肝肿瘤的分类,这将为肝LELC的精准诊断及治疗提供新思路。

Epstein-Barr病毒与肝损伤相关性的研究进展

EB病毒(Epstein-Barr Virus,EBV)作为常见的非嗜肝DNA病毒之一,早已被研究证实可以导致肝脏损伤(Liver injury)并引起肝功能异常,且已成为临床医生对肝功能异常患者筛查的重要指标之一。但目前尚缺乏对既往有关其感染所致肝损伤的研究成果的有效整合。本文通过梳理相关文献系统、全面探讨EBV与肝损伤相关性的研究进展,包括EBV概述、感染的现状、传播方式、所致疾病类型、其致肝损伤可能的机制和对临床诊疗的影响及EBV相关性肝损伤未来的研究方向。本文表明EBV感染所致肝损伤可能持续存在并导致严重后果,为全球带来巨大的疾病负担。因此,临床医生必须对其予以足够的重视,以期早期识别,并尽早采取有效措施使患者能最大获益。

传染性单核细胞增多症患儿调节性T细胞/辅助性T细胞17免疫失衡与治疗后Epstein-Barr病毒-DNA仍阳性的相关性研究

目的探讨传染性单核细胞增多症患儿调节性T细胞(regulatory T cell,Treg)/辅助性T细胞(helper T cell,Th)17免疫失衡与治疗后Epstein-Barr病毒(EBV)-DNA仍阳性的相关性,为传染性单核细胞增多症的治疗及预后评估提供重要标志物。方法以2021年1月至2023年6月就诊于秦皇岛市工人医院的88例传染性单核细胞增多症患儿作为研究对象。患儿接受基于阿昔洛韦或更昔洛韦的标准化治疗并持续随访,根据治疗14d时患儿EBV-DNA载量是否仍为阳性分为EBV-DNA阴性组(n=70)和EBV-DNA阳性组(n=18)。对比两组患儿一般临床资料、治疗相关特征、治疗前T细胞亚群、炎性细胞因子、免疫球蛋白等指标的差异。将单因素分析有意义的指标进行Spearman相关性分析及多因素Logistic回归分析,评价各差异性指标与传染性单核细胞增多症患儿治疗14d后EBV-DNA仍阳性的相关性和危险因素。结果EBV-DNA阳性组患儿平均住院时间、平均体温恢复时间、淋巴结肿大恢复时间均显著长于EBV-DNA阴性组患儿(P<0.05);EBV-DNA阳性组患儿平均CD4^(+)T淋巴细胞比例、CD4^(+)/CD8^(+)比值、Treg细胞比例、Treg/Th17比值、血清IL-4水平均显著低于EBV-DNA阴性组患儿,平均Th17细胞比例及血清IFN-γ水平均显著高于EBV-DNA阴性组患儿(P<0.05);多因素Logistic回归分析表明传染性单核细胞增多症患儿CD4^(+)T淋巴细胞比例及Treg细胞比例较低、Th17细胞比例较高及Treg/Th17比值较低均是规范治疗14d后EBV-DNA仍阳性的危险因素(P<0.05)。结论传染性单核细胞增多症患儿治疗前T细胞亚群比例特征、Treg/Th17免疫失衡严重程度、Th1/Th2细胞因子水平及免疫球蛋白水平与治疗14d后EBV-DNA仍阳性具有显著相关性,密切监测并促进患儿免疫-炎症水平恢复平衡对于提高传染性单核细胞增多症治疗预后具有重要临床意义。

Prognostic value of plasma Epstein-Barr virus DNA level during posttreatment follow-up in the patients with nasopharyngeal carcinoma having undergone intensity-modulated radiotherapy

Background: The value of Epstein-Barr virus(EBV) DNA assay during posttreatment follow-up of the patients with nasopharyngeal carcinoma(NPC) presenting with different pretreatment plasma EBV DNA levels remains unclear. In the present study, we aimed to evaluate the prognostic value of plasma EBV DNA assay during posttreatment followup in the patients with NPC who have undergone intensity-modulated radiotherapy.Methods: The medical records of 385 NPC patients treated with intensity-modulated radiotherapy between November 2009 and February 2012 were reviewed. All patients underwent plasma EBV DNA assays before treatment, within3 months after treatment, and then every 3-12 months during posttreatment follow-up period. The recurrence rates for patients with different pretreatment and posttreatment follow-up plasma EBV DNA levels were analyzed.Results: Of the 385 patients, 267(69.4%) had detectable pretreatment plasma EBV DNA(> 0 copy/mL) and 93(24.2%) had detectable posttreatment EBV DNA during a median follow-up of 52.8 months(range 9.3-73.8 months).Detectable EBV DNA during posttreatment follow-up was found in 14.4%(17/118) and 28.5%(76/267) of patients with undetectable and detectable pretreatment EBV DNA, respectively, and was significantly associated with tumor recurrence in both patient groups. EBV DNA was detectable in 12.8%(40/313) of patients who remained disease-free,56.4%(22/39) of patients with locoregional recurrence alone, and 93.9%(31/33) of patients with distant metastasis as the first recurrence event(P < 0.001); 6.5%(19/292) of patients with undetectable EBV DNA and 57.0%(53/93) of patient with detectable EBV DNA during posttreatment follow-up experienced tumor recurrence. Compared with other cut-off values, the cut-off value of 0 copy/mL for EBV DNA during posttreatment follow-up had the highest area under the ROC curve(AUC) value(0.804,95% confidence interval 0.741-0.868) for predicting tumor recurrence(sensitivity, specificity, and accuracy: 73.6%, 87.2%, and 84.7%, respectively).Conclusion: Plasma EBV DNA level during posttreatment follow-up is a good marker for predicting distant metastasis but not locoregional recurrence in the patients with NPC irrespective of the pretreatment EBV DNA levels.

Prognostic values of the integrated model incorporating the volume of metastatic regional cervical lymph node and pretreatment serum Epstein-Barr virus DNA copy number in predicting distant metastasis in patients with N1 nasopharyngeal carcinoma

Background: According to the 7 th edition of the American Joint Committee on Cancer(AJCC) staging system, over50% of patients with nasopharyngeal carcinoma(NPC) have N1 disease at initial diagnosis. However, patients with N1 NPC are relatively under-researched, and the metastasis risk of this group is not well-stratified. This study aimed to evaluate the prognostic values of gross tumor volume of metastatic regional lymph node(GTVnd) and pretreatment serum copy number of Epstein-Barr virus(EBV) DNA in predicting distant metastasis of patients with N1 NPC, and to develop an integrated prognostic model that incorporates GTVnd and EBV DNA copy number for this group of patients.Methods: The medical records of 787 newly diagnosed patients with nonmetastatic, histologically proven N1 NPC who were treated at Sun Yat-sen University Cancer Center between November 2009 and February 2012 were analyzed. Computed tomography-derived GTVnd was measured using the summation-of-area technique. Blood samples were collected before treatment to quantify plasma EBV DNA. The receiver operating characteristic(ROC) curve analysis was used to evaluate the cut-off point for GTVnd, and the area under the ROC curve was used to assess the predicted validity of GTVnd. The survival rates were assessed by Kaplan-Meier analysis, and the survival curves were compared using a log-rank test. Multivariate analysis was conducted using the Cox proportional hazard regression model.Results: The 5-year distant metastasis-free survival(DMFS) rates for patients with GTVnd > 18.9 vs.≤ 18.9 mL were82.2% vs. 93.2%(P < 0.001), and for patients with EBV DNA copy number > 4000 vs. < 4000 copies/mL were 83.5% vs.93.9%(P < 0.001). After adjusting for GTVnd, EBV DNA copy number, and T category in the Cox regression model, both GTVnd > 18.9 mL and EBV DNA copy number > 4000 copies/mL were significantly associated with poor prognosis(both P < 0.05). According to combination of GTVnd and EBV DNA copy number, all patients were divided into low-,moderate-, and high-risk groups, with the 5-year DMFS rates of 96.1,87.4, and 73.8%, respectively(P < 0.001). Multivariate analysis confirmed the prognostic value of this model for distant metastatic risk stratification(hazard ratio [HR],4.17; 95% confidence interval [CI] 2.34-7.59; P < 0.001).Conclusions: GTVnd and serum EBV DNA copy number are independent prognostic factors for predicting distant metastasis in NPC patients with N1 disease. The prognostic model incorporating GTVnd and EBV DNA copy number may improve metastatic risk stratification for this group of patients.

Plasma Epstein-Barr virus DNA as a biomarker for nasopharyngeal carcinoma

Nasopharyngeal carcinoma(NPC)is common in southern China and Southeast Asia.Epstein-Barr virus(EBV)infection is an important etiology for NPC,and EBV genome can be detected in almost all tumor tissues of NPC in this region.Plasma EBV DNA,when quantitatively analyzed using real-time polymerase chain reaction(PCR),has been developed as a biomarker for NPC.In this review,the different clinical applications of plasma EBV DNA in the management of NPC,including screening,monitoring,and prognostication,are discussed.In addition,the biological issues of circulating EBV DNA,including the molecular nature and clearance kinetics,are also explored.

Epstein Barr virus-positive mucocutaneous ulcer of thecolon associated Hodgkin lymphoma in Crohn＇s disease

Epstein Barr virus （EBV） positive mucocutaneous ulcers（EBVMCU） form part of a spectrum of EBV-associatedlymphoproliferative disease. They have been reportedin the setting of immunosenescence and iatrogenicimmunosuppression, affecting the oropharyngeal mucosa,skin and gastrointestinal tract （GIT）. Case reports andseries to date suggest a benign natural history respondingto conservative management, particularly in the GIT. Wereport an unusual case of EBVMCU in the colon, arisingin the setting of immunosuppression in the treatment ofCrohn＇s disease, with progression to Hodgkin lymphoma18 mo after cessation of infliximab. The patient presentedwith multiple areas of segmental colonic ulceration,histologically showing a polymorphous infiltrate withEBV positive Reed-Sternberg-like cells. A diagnosisof EBVMCU was made. The ulcers failed to regressupon cessation of infliximab and methotrexate for 18mo. Following commencement of prednisolone for herCrohn＇s disease, the patient developed widespreadHodgkin lymphoma which ultimately presented as alife-threatening lower GIT bleed requiring emergencycolectomy. This is the first report of progression ofEBVMCU to Hodgkin lymphoma, in the setting of ongoingiatrogenic immunosuppression and inflammatory boweldisease.

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 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 were173 male and 157 female patients (male/female ratio1.1/1). 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.

Epstein-Barr virus and Burkitt lymphoma

In 1964,a new herpesvirus,Epstein-Barr virus(EBV),was discovered in cultured tumor cells derived from a Burkitt lymphoma(BL)biopsy taken from an African patient.This was a momentous event that reinvigorated research into viruses as a possible cause of human cancers.Subsequent studies demonstrated that EBV was a potent growth-transforming agent for primary B cells,and that all cases of BL carried characteristic chromosomal translocations resulting in constitutive activation of the c-MYC oncogene.These results hinted at simple oncogenic mechanisms that would make Burkitt lymphoma paradigmatic for cancers with viral etiology.In reality,the pathogenesis of this tumor is rather complicated with regard to both the contribution of the virus and the involvement of cellular oncogenes.Here,we review the current understanding of the roles of EBV and c-MYC in the pathogenesis of BL and the implications for new therapeutic strategies to treat this lymphoma.

Epstein-Barr virus-associated gastric carcinoma in Kazakhstan

AIM: To investigate the incidence of Epstein-Barr virusassociated gastric cancer (EBV-GC) in Kazakhstan and to compare it with that in Russia, Western and Asian countries in order to evaluate the significance of epidemiopathoiogic and ethnic factors.METHODS: In situ hybridization (ISH) of EBV-encoded small RNA-1 (EBER-1) was used to identify the presence of EBER-1 signal in 139 formalin-fixed and paraffin-embedded GC tissues from Kazakhstan.RESULTS: EBER-1 expression was observed in the nuclei of 10% of the cases of GC (14/139), but not in the surrounding normal mucosa. The incidence of the diffuse type of EBV-GC was significantly higher in Kazakhstan (14%, 13/91) than that of the intestinal type (2%, 1/48).Furthermore, the incidence was significantly higher in males (14%, 12/89) than in females (3.7%, 2/53) from all countries. The overall incidence of EBV-GC increased from 6.7% in Asian countries to 8.7% in Russia, 10.1% in Kazakhstan and 16% in Western countries.CONCLUSION: Geographical differences in the incidence of EBV-GC may reflect the epidemiologic factors and/or dietary habits independent of histological type and sex.

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.