Epstein-Barr Virus Type Research Articles

Burkitt Lymphoma in Brazil Is Characterized by Geographically Distinct Clinicopathologic Features

Burkitt lymphoma (BL) is a highly aggressive non-Hodgkin lymphoma with a consistent MYC translocation. Epstein-Barr virus (EBV) has been associated with BL at different frequencies, depending on the clinical variant and geographic regions. This is a large-scale study of BL in Brazil, including 234 patients from 5 geographic regions that are widely disparate socioeconomically, including pediatric (61.1%) and adult (37.6%) populations. EBV was present in 52.6% of all BL cases, varying from 29% (12/42) in the South to 76% (13/17) in the North. Most of the cases were EBV type A. The frequency was higher in the pediatric group, and EBV association within this age range predominated in all regions except the South. Expression of p53 protein was observed in 16.2%, and only rare cases showed p63 expression. BL in Brazil is regionally distinct and has a low incidence of p53 overexpression and a higher-than-expected association with EBV in sporadic cases.

Detection of Herpesviruses and Periodontal Pathogens in Subgingival Plaque of Patients With Chronic Periodontitis, Generalized Aggressive Periodontitis, or Gingivitis

Herpesviruses may be related to the etiology of aggressive periodontitis (AgP) and chronic periodontitis (CP) by triggering periodontal destruction or by increasing the risk for bacterial infection. This case-control study evaluated the presence of herpes simplex virus type I (HSV-1), Epstein-Barr virus type I (EBV-1), human cytomegalovirus (HCMV), Aggregatibacter actinomycetemcomitans (previously Actinobacillus actinomycetemcomitans), Porphyromonas gingivalis, Prevotella intermedia, and Tannerella forsythia (previously T. forsythensis) in patients with generalized AgP (AgP group), CP (CP group), or gingivitis (G group) and in healthy individuals (C group). Subgingival plaque samples were collected with paper points from 30 patients in each group. The nested polymerase chain reaction (PCR) method was used to detect HSV-1, EBV-1, and HCMV. Bacteria were identified by 16S rRNA-based PCR. HSV-1, HCMV, and EBV-1 were detected in 86.7%, 46.7%, and 33.3% of the AgP group, respectively; in 40.0%, 50.0%, and 46.7% of the CP group, respectively; in 53.3%, 40.0%, and 20.0% of the G group, respectively; and in 20.0%, 56.7%, and 0.0% of the C group, respectively. A. actinomycetemcomitans was detected significantly more often in the AgP group compared to the other groups (P <0.005). P. gingivalis and T. forsythia were identified more frequently in AgP and CP groups, and AgP, CP, and G groups had higher frequencies of P. intermedia compared to the C group. In Brazilian patients, HSV-1 and EBV-1, rather than HCMV, were more frequently associated with CP and AgP.

Viral Studies in Burkitt Lymphoma

Burkitt lymphoma (BL) is a highly aggressive non-Hodgkin lymphoma, composed of a monomorphic population of medium-sized B cells with a high proliferation rate and a consistent MYC translocation. Epstein-Barr virus (EBV) has been associated with BL with different frequencies depending on the clinical variant. Kaposi sarcoma-associated herpesvirus, or human herpesvirus 8 (HHV-8), infects a wide range of normal cells, having a well-established role in the pathogenesis of various neoplasms, including Kaposi sarcoma, primary effusion lymphoma, multicentric Castleman disease (MCD) and MCD-associated plasmablastic lymphoma. In secondary immunodeficiencies, such as HIV-1 infection and organ transplantation, HHV-8 is considered an opportunistic pathogen linked to the development of lymphomas in patients with AIDS and HIV + patients. We studied the association of EBV and HHV-8 by immunohistochemical analysis, in situ hybridization, and polymerase chain reaction in a large number of well-characterized BLs. EBV was present in 45.0% of all BL cases with higher incidence in the pediatric group; most cases were EBV type A. We found no association of BL with HHV-8 in EBV + BL or in EBV-cases, including the HIV + BL group.

Epstein-Barr virus nuclear antigen-2 detection and typing in immunocompromised children correlated with lymphoproliferative disorder biopsy findings

Epstein-Barr virus (EBV), the causative agent of infectious mononucleosis, plays a significant role as a cofactor in the process of tumorigenesis, and has consistently been associated with a variety of malignancies especially in immunocompromised patients. Forty-four children and adolescents (21 liver transplant patients, 7 heart transplant, 5 AIDS, 3 autoimmune hepatitis, 2 nephritic syndromes, 2 medullar aplasia, 2 primary immunodeficiency disorder patients, 1 thrombocytopenic purpura and 1 systemic lupus erythematosus) presenting with chronic active EBV infection (VCA-IgM persistently positive; VCA-IgG > 20 AU/mL and positive IgG _ EBNA) had peripheral blood samples obtained during clinically characterized EBV reactivation episodes. DNA samples were amplified in order to detect and type EBV on the basis of the EBNA-2 sequence (EBNA2 protein is essential for EBV-driven immortalization of B lymphocytes). Although we have found a predominance of type 1 EBNA-2 virus (33/44; 75%), 10 patients (22.73%) carried type 2 EBNA-2, and one liver transplant patient (2.27%) a mixture of the two types, the higher proportion of type 2 EBV, as well as the finding of one patient bearing the two types is in agreement with other reports held on lymphoproliferative disorder (LPD) patients, which analyzed tumor biopsies. We conclude that EBNA-2 detection and typing can be performed in peripheral blood samples, and the high prevalence of type 2 in our casuistic indicates that this population is actually at risk of developing LPD, and should be monitored.

Amphipathic DNA Polymers Exhibit Antiherpetic Activity In Vitro and In Vivo

Phosphorothioated oligonucleotides have a sequence-independent antiviral activity as amphipathic polymers (APs). The activity of these agents against herpesvirus infections in vitro and in vivo was investigated. The previously established sequence-independent, phosphorothioation-dependent antiviral activity of APs was confirmed in vitro by showing that a variety of equivalently sized homo- and heteropolymeric AP sequences were similarly active against herpes simplex virus type 1 (HSV-1) infection in vitro compared to the 40mer degenerate parent compound (REP 9), while the absence of phosphorothioation resulted in the loss of antiviral activity. In addition, REP 9 demonstrated in vitro activity against a broad spectrum of other herpesviruses: HSV-2 (50% effective concentration [EC(50)], 0.02 to 0.06 microM), human cytomegalovirus (EC(50), 0.02 to 0.13 microM), varicella zoster virus (EC(50), <0.02 microM), Epstein-Barr virus (EC(50), 14.7 microM) and human herpesvirus types 6A/B (EC(50), 2.9 to 10.2 microM). The murine microbicide model of genital HSV-2 was then used to evaluate in vivo activity. REP 9 (275 mg/ml) protected 75% of animals from disease and infection when provided 5 or 30 min prior to vaginal challenge. When an acid-stable analog (REP 9C) was used, 75% of mice were protected when treated with 240 mg/ml 5 min prior to infection (P < 0.001), while a lower dose (100 mg/ml) protected 100% of the mice (P < 0.001). The acid stable REP 9C formulation also provided protection at 30 min (83%, P < 0.001) and 60 min (50%, P = 0.07) against disease. These observations suggest that APs may have microbicidal activity and potential as broad-spectrum antiherpetic agents and represent a novel class of agents that should be studied further.

Differential Gene Regulation by Epstein-Barr Virus Type 1 and Type 2 EBNA2

A transfection assay with a lymphoblastoid cell line infected with Epstein-Barr virus was used to compare the abilities of type 1 and type 2 EBNA2 to sustain cell proliferation. The reduced proliferation in cells expressing type 2 EBNA2 correlated with loss of expression of some cell genes that are known to be targets of type 1 EBNA2. Microarray analysis of EBNA2 target genes identified a small number of genes that are more strongly induced by type 1 than by type 2 EBNA2, and one of these genes (CXCR7) was shown to be required for proliferation of lymphoblastoid cell lines. The Epstein-Barr virus LMP1 gene was also more strongly induced by type 1 EBNA2 than by type 2, but this effect was transient. Type 1 and type 2 EBNA2 were equally effective at arresting cell proliferation of Burkitt's lymphoma cell lines lacking Epstein-Barr virus and were also shown to cause apoptosis in these cells. The results indicate that differential gene regulation by Epstein-Barr virus type 1 and type 2 EBNA2 may be the basis for the much weaker B-cell transformation activity of type 2 Epstein-Barr virus strains compared to type 1 strains.

Association between EBNA2 and LMP1 subtypes of Epstein-Barr virus and nasopharyngeal carcinoma in Thais

Background Nasopharyngeal carcinoma (NPC) is an Epstein-Barr virus (EBV)-associated malignancy that is common in Thailand. The association of the EBV nuclear antigen 2 gene ( EBNA2) and the latent membrane protein 1 gene ( LMP1) with NPC is unclear. Objective To determine the association between EBNA2 and LMP1 subtypes of EBV and NPC in Thais. Study design EBV DNA from blood samples of 75 Thai patients with NPC and 44 age-matched controls was examined by PCR for EBNA2 subtypes ( EBV type 1 and type 2) and LMP1 subtypes (wild-type LMP1 ( wt-LMP1) and LMP1 containing a 30-bp deletion ( del-LMP1)). Results The frequencies of EBV type 1 in cases (96.0%) and controls (97.7%) were similar. The frequency of del-LMP1 in cases (58.7%) was higher than in controls (36.4%) ( p = 0.023). Among NPC patients, the frequency of del-LMP1 in stages III and IV (65.6%) was higher than in stages I and II (18.2%) ( p = 0.006). By analyzing nucleotide sequence of the LMP1 region, a new subtype, Thai1, was identified. Conclusion LMP1 subtypes of EBV may be involved in NPC susceptibility. The del-LMP1 variant may be a useful molecular marker for early detection, diagnosis and prognosis of Thai patients with NPC.

EBV-1 and HCMV in aggressive periodontitis in Brazilian patients

The purpose of the present investigation was to compare the presence of Epstein-Barr virus type 1 (EBV-1) and of Human Cytomegalovirus (HCMV) in crevicular fluid samples from deep and shallow periodontal pocket sites of Brazilian patients with aggressive periodontitis. A total of 30 systemically healthy patients with aggressive periodontitis participated in the study. Paper points were inserted into 2 gingivitis sites (<3 mm) and into 2 periodontitis sites (>5 mm) in each patient. PCR assay was used to identify genomic copies of HCMV and EBV-1. Twenty-three patients (77%) were positive for EBV-1, while only 2 patients (6%) were positive for HCMV. The McNemar test revealed a positive association between EBV-1 and periodontal lesions (p=0.043). Thirty-four (57%) out of 60 periodontitis sites were positive for EBV-1, whereas 18 (30%) gingivitis sites were positive (p=0.01). Only two sites (6.7%) were positive for HCMV. No positive association was found between HCMV and periodontitis or gingivitis (p=0.479). The elevated occurrence of EBV-1 DNA in periodontal pockets of patients with aggressive periodontitis supports a possible periodontopathic role of this virus.

Prevalence of Epstein-Barr Virus Type 1 in Patients with Chronic Periodontitis by Nested-PCR

The present study evaluated the subgingival presence of Epstein-Barr virus type 1 (EBV-1) in patients with chronic periodontitis with nested-PCR. Subgingival plaque samples from 61 patients with chronic periodontitis with Probing Depth (PD) > or = 6 and 40 healthy controls were collected by sterile curette. DNA was extracted. A nested Polymerase Chain Reaction (PCR) method determined presence of EBV-1. The study included 61 patients (34 women, 27 men; 24-69 years of age; mean 43) and 40 periodontally health controls (22 Women, 18 men, 21-69 years in age; mean 41.35%). EBV type 1 was detected in 37 samples (60.7%) and 1 samples (2.5%) of chronic periodontitis patients and healthy subjects, respectively. This study demonstrated that EBV-1 infection is associated with the activity of chronic periodontitis.

Case of Moyamoya Disease in a Patient With Advanced Acquired Immunodeficiency Syndrome

Moyamoya disease is an occlusion of the terminal portion of internal carotid arteries and proximal portion of middle and anterior cerebral arteries of unknown origin. Moyamoya syndrome is associated with meningitis, tuberculosis, syphilis, head trauma, head irradiation, brain tumor, von Recklinghausen's disease, tuberous sclerosis, Marfan syndrome, sickle cell anemia, arteriosclerosis, hypertension, and oral contraceptive use. To our knowledge, acquired immunodeficiency syndrome (AIDS) as a cause of moyamoya syndrome has not been reported in an adult population. We report a case of moyamoya syndrome in a patient with AIDS and without other conditions associated with occlusion of the circle of Willis and formation of collateral network at the base of the brain and basal ganglia. We present a case report. A 29-year-old woman with an 8-year history of AIDS on multiple antiretroviral medications presented with recurrent tingling of the left extremities which 1 month later progressed to mild hemiparesis and dysarthria. During the next few months the patient developed progressive cognitive decline and on-and-off fluctuations in the degree of hemiparesis. Brain magnetic resonance imaging showed multiple small subcortical infarct's in both parietal lobes. Magnetic resonance angiography showed occlusion of middle cerebral arteries distal internal carotid arteries, with prominent collateral network. Cerebral angiography confirmed moyamoya pattern. Lumbar puncture showed: white blood cell count 1, red blood cell count 418, protein 56, glucose 53, negative bacterial and acid-fast bacilli smear and culture, negative VDRL test, India ink, cryptococcal antigen, cytology and negative polymerase chain reaction for cytomegalovirus, Epstein-Barr virus, varicella-zoster virus, and herpes simplex virus type 1 and 2. Electroencephalography showed diffuse background slowing. We hypothesize that human immunodeficiency virus (HIV) caused central nervous system vasculitis, which eventually led to formation of moyamoya pattern. No other definite causes of central nervous system vasculitis were found in our patient. Cerebrovascular disorders should be considered in patients with HIV/AIDS with focal neurologic deficit. Moyamoya syndrome as a cause of stroke should be considered in patients with HIV/AIDS, especially as survival improves.

Studies of herpesvirus infection in chronic fatigue syndrome.

The relationship of herpesviruses to chronic fatigue syndrome has received considerable attention over the past decade. Data suggesting an association fall into three major categories. First, among acute precipitants of the syndrome are primary infections with some herpesviruses, most notably Epstein-Barr virus and cytomegalovirus. Second, a series of studies have detailed elevations of antibodies to most herpesviruses in selected chronic fatigue syndrome populations, with Epstein-Barr virus and human herpes type 6 being the objects of most scrutiny. Third, one recent study reported a greater ease of recovery of human herpes virus type 6 from chronic fatigue syndrome patients. This review article critically examines the cumulative data regarding an association between one or more herpesviruses and the chronic fatigue syndrome in the context of the known biology and epidemiology of these agents. In view of these, and additional considerations regarding study methodologies, the conclusion is drawn that herpesviruses are not dominant causes of the chronic fatigue syndrome and may not even be necessary to the perpetuation of the illness, but it is premature to dismiss entirely this latter possibility.

Correlation between Infections with Different Genotypes of Human Cytomegalovirus and Epstein-Barr Virus in Subgingival Samples and Periodontal Status of Patients

Accumulating evidence indicates that herpesviruses may be putative pathogens in various types of periodontal diseases. The present study was performed to examine infections with different genotypes of human cytomegalovirus (HCMV) and Epstein-Barr virus (EBV) in subgingival samples from a Chinese population and to analyze the correlation with periodontal status. A nested PCR assay was used to identify the presence of HCMV, EBV type 1 (EBV-1), and EBV-2; and the amplicons were further analyzed by restriction fragment length polymorphism analysis. HCMV was detected in 79.0% of 143 chronic periodontitis (CP) patients, 78.5% of 65 gingivitis patients, and 76.3% of 76 periodontally healthy individuals, while EBV was found in 63.6%, 32.3%, and 30.3% of the three groups of subjects, respectively. The HCMV-positive PCR products from all the samples were identified as corresponding to gB genotype I (gB-I) or gB-II. HCMV gB-II (62.9%), EBV-1 (43.4%), and EBV-2 (18.2%) were associated with CP at higher frequencies (P < 0.05), whereas HCMV gB-I was more often observed in gingivitis patients (40.0%) and healthy individuals (40.8%) (P < 0.05). Furthermore, a higher rate of coinfection with HCMV and EBV was shown in CP patients (52.4%), especially dual infections with HCMV gB-II and EBV-1 (30.8%) or HCMV gB-II and EBV-2 (12.6%), compared with the rates of single infections with HCMV or EBV (P < 0.05). Infection with HCMV gB-II, EBV-1, or EBV-2 was correlated with higher rates of bleeding on probing (P < 0.05). In patients infected with HCMV gB-II or both HCMV and EBV, including HCMV gB-II and EBV-1, a deeper probing depth or more serious attachment loss was found (P < 0.05). These findings clearly indicate that HCMV gB-II is the dominant genotype detected in subgingival samples in CP. HCMV gB-II infection and HCMV gB-II coinfection with EBV-1 are closely associated with periodontal tissue inflammation and destruction.

Epstein?Barr virus genotypes in multiple sclerosis

Multiple sclerosis (MS) is associated with Epstein-Barr virus (EBV) infection, but the relationship between the virus and the disease is not clear. As many different types of EBV exist, it is possible that MS is caused by one particular type of EBV. Objectives - The aim of this study was to determine whether MS is associated with a particular genotype of EBV. We collected blood from MS patients and controls, amplified and sequenced the latent membrane protein-1 (LMP-1) gene, and compared the groups. We found a variety of LMP-1 sequences in both MS and controls, with no significant differences between the groups. Conclusion - We conclude that MS is not associated with a particular genotype of EBV.

Endotoxins do not influence transplacental transmission of lymphotropic human herpesviruses and human papillomaviruses into amniotic fluid taken from healthy mothers before parturition in Hungary

Pregnant women were examined following healthy pregnancies at term. Amniotic fluids were sampled before arteficial rupture of membranes using closed vacutainer system. Blood samples were also taken from the pregnants simultaneously. Endotoxin concentrations of amniotic fluids were tested by the semiquantitative Limulus amebocyte lysate. Both amniotic fluids and blood samples were tested for the presence of DNA of lymphotropic human herpesviruses. The DNA of human papillomaviruses were tested only in the amniotic fluid samples. One-third of the amniotic fluids tested were found to contain measurable amounts of endotoxin. Lymphotropic herpesvirus DNA was deteced in every fourth amniotic fluid sample and in every 8th blood sample. The prevalence of papillomaviruses was 7 of 96 samples. No significant correlation was found between the presence of endotoxin and viruses in the amniotic fluids. Epstein-Barr virus, human cytomegalovirus and human herpesvirus type 7 were found more frequently in the amniotic fluids than in blood samples (7 to 1). The prevalence of human herpesvirus 6 and 8 was higher in the blood samples than that in the amniotic fluids. The mean weight of the neonates were not impaired significantly by the presence of either viruses or endotoxin. Possible post partum consequences, i.e. partial immunotolerance to viruses is discussed.

Molecular analysis of the Epstein-Barr virus LMP1 in Hodgkin lymphoma from Argentina and Brazil: Identification of a distinct LMP1 deleted variant

21099 Background: Epstein Barr virus (EBV), a human oncogenic virus, has two types, EBV1 and 2, and several polymorphic markers allow individual variants to be distinguished. Variations in EBV latent membrane protein 1 (LMP1) gene could define a more oncogenic strain or reflect geographic EBV origin. By sequence analysis of C-ter, N-ter and promoter (prom) regions, 4 distinct EBV groups (A to D) have been defined. Aim: To analyze LMP1 molecular variability of two different groups of Hodgkin`s lymphoma (HL) from the same geographic area. Methods: EBV association by EBERs in situ hibridization and LMP1 immunohistochemistry was analyzed in 27 HL from Argentina (Arg) and 36 HL from Brazil (Br). EBV type was assessed by EBNA PCR. C-ter LMP1 PCR was done in all cases. Sequencing of C-ter, N-ter and prom regions was done in 16 patients. Results: 21/27 (78%) Arg HL and 31/36 (86%) Br HL were EBV1, while 6/27 (22%) and 4/36 (11%) were EBV2, respectively (p= 0.29). Coinfection was observed in 1 (3%) Br HL. LMP1 deleted (del) variant was observed in 20/27 (74%) Arg HL and 20/36 (55%) Br HL (p= 0.18), as well as in non-neoplastic controls, 4/11 and 3/10 (36 and 30%) from Arg and Br respectively. Most LMP1 del displayed high number (5–7) of 33bp repeats (86% LMP1 del Br HL and 77% LMP1 del Arg HL) compared with LMP1 wt that exhibited low number (3–4) 33bp repeats (68% LMP1 wt Br HL and 100% LMP1 wt Arg HL). Analysis of LMP1 sequences showed that: LMP1 wt C-ter regions had unmutated N-ter and prom as B95.8, A and B groups (31%), except for a case showing new mutations. LMP1 del C-ter regions showed molecular identity with C group, but they showed new, undescribed mutations in prom and N-ter (63%). Conclusions: We found high frequency of LMP1 del variants in HL from Argentina and Brazil, which was associated with high number of 33bp repeats in C-ter region. This suggests a role for this variant in lymphomagenesis. A new molecular variant with characteristic promoter and N-ter mutations was identified in LMP1 del cases, which could be proposed as a regional South American variant. No significant financial relationships to disclose.

Extranodal NK/T-cell Lymphoma, Nasal Type: Study of Clinicopathologic and Prognosis Factors in a Series of 78 Cases From Peru

It is well known that extranodal NK/T-cell lymphoma (NK/TCL) nasal type clusters in Asian countries. A large series of 78 cases of nasal NK/TCL from Peru is analyzed in the present study. Two histologic groups 1 (monomorphic) and 2 (polymorphic), were segregated according to the proportion of large cells (above and below 30%, respectively). Catalyzed signal amplification technique was performed for enhancement of immunohistochemistry reactivities. Epstein-Barr virus (EBV) sequences and types were investigated using polymerase chain reaction. Clinical characteristics, stage, outcome, and response to treatment were evaluated in both groups. Fourteen cases (18%) and 64 cases (82%) corresponded to groups 1 and 2, respectively. Except for nasal obstruction, more common in group 2, all other symptoms were similar in both groups. Local extension and staging were also comparable. Both groups showed CD3c+ CD2+ CD56+ CD3s- CD20- immunophenotype. All cases were positive for EBV. In this series type-2 EBV was found more frequent than type-1 EBV, contrarily to that observed in Asian series. However, about one-third of cases simultaneously harbored both viral types. Both groups received an average of 50-Gy dose of radiation therapy (RT), with or without chemotherapy. Complete therapeutic response was achieved in 89% of group 1 and in 74% of group 2, but this difference was not statistically significant. There were no significant differences between the groups regarding disease-free survival, failure-free survival, relapse, and overall survival. The overall survival, in both groups, was longer for patients treated with RT alone compared with those treated with combined RT therapy and chemotherapy. The present study has shown that dividing nasal NK/TCL in monomorphic and polymorphic variants, according to frequency of large cells, does not correlate with clinical and prognostic factors.

Lyme borreliosis and multiple sclerosis are associated with primary effusion lymphoma

Multiple sclerosis (MS) is a chronic disease of the central nervous system characterized by chronic inflammation and demyelination. Studies suggested that the viral, especially Epstein-Barr virus infection, and bacterial infections, especially Borrelia burgdorferi infection, play a role in etiology of MS. MS prevalence parallels the distribution of the Lyme disease pathogen B. burgdorferi. Criteria used for diagnosis of MS can also be fulfilled in other conditions such as Lyme disease, a multisystem disorder resulting from infection by the tick-borne spirochete, B. burgdorferi. In the late period of Lyme disease demyelinating involvement of central nervous system can develop and MS can be erroneously diagnosed. A Lyme borreliosis can mimick central nervous system lymphoma. Also, B. burgdorferi has been implicated not only in etiology of MS, but also in etiology of lymphoma. Studies suggested that there is an increased risk of non-Hodgkin lymphoma in patients, who had a history of autoimmune diseases such as MS and that both non-Hodgkin's lymphomas and Hodgkin's disease were associated with Epstein-Barr virus infection. A small group of lymphomas called primary effusion lymphomas (PEL) is a recently individualized form of non-Hodgkin's lymphoma (WHO classification) that exhibit exclusive or dominant involvement of serous cavities, without a detectable solid tumor mass. These lymphomas have also been linked to Epstein-Barr virus and human herpes virus type 8 infections but virus negative cases have been described. Therefore, we propose that MS and neuroborreliosis are linked to central nervous system primary effusion lymphomas. As a first step in confirming or refuting our hypotheses, we suggest a thorough study of CSF in the patients suspected for the diagnosis of MS and Lyme borreliosis.

Prediction model building and feature selection with support vector machines in breast cancer diagnosis

Breast cancer is a serious problem for the young women of Taiwan. Some medical researches have proved that DNA viruses are one of the high-risk factors closely related to human cancers. Five DNA viruses are studied in this research: specific types of HSV-1 (herpes simplex virus type 1), EBV (Epstein-Barr virus), CMV (cytomegalovirus), HPV (human papillomavirus), and HHV-8 (human herpesvirus-8). The purposes of this study are to obtain the bioinformatics about breast tumor and DNA viruses, and to build an accurate diagnosis model about breast cancer and fibroadenoma. Research efforts have reported with increasing confirmation that the support vector machine (SVM) has a greater accurate diagnosis ability. Therefore, this study constructs a hybrid SVM-based strategy with feature selection to render a diagnosis between the breast cancer and fibroadenoma and to find the important risk factor for breast cancer. The results show that {HSV-1, HHV-8} or {HSV-1, HHV-8, CMV} are the most important features and that the diagnosis model achieved high classification accuracy, at 86% of average overall hit rate. A Linear discriminate analysis (LDA) diagnosis model is also constructed in this study. The LDA model shows that {HSV-1, HHV-8, EBV} or {HSV-1, HHV-8} are significant factors which are similar to that of the SVM-based classifier. However, the classificatory accuracy of the SVM-based classifier is slightly better than that of LDA in the negative hit ratio, positive hit ratio, and overall hit ratio.

A Cohort Study among University Students: Identification of Risk Factors for Epstein‐Barr Virus Seroconversion and Infectious Mononucleosis

A vaccine against Epstein-Barr virus (EBV) infection is in clinical trials. Up-to-date information on risk factors for EBV infection and infectious mononucleosis (IM) among young adults is required to inform a vaccination strategy. We carried out a prospective study on a cohort of university students. All EBV-seronegative students were asked to report symptoms of IM and were followed up 3 years later to undergo repeat EBV testing and to complete a lifestyle questionnaire. EBV typing was performed for these subjects, as well as for students who were EBV seropositive at enrollment and for additional students with IM. A total of 510 students (25%) who took part in the study were EBV seronegative when they entered the university; of the 241 who donated a second blood sample 3 years later, 110 (46%) had seroconverted to EBV, 27 (25%) of whom developed IM [corrected] Penetrative sexual intercourse was a risk factor for EBV seroconversion (P = .004), but neither condom use nor oral sex significantly altered the rate of seroconversion. EBV type 1 was significantly overrepresented in IM, compared with silent seroconversion (P = .001). Our findings suggest that acquisition of EBV is enhanced by penetrative sexual intercourse, although transmission could occur through related sexual behaviors, such as "deep kissing." We also found that EBV type 1 infection is significantly more likely to result in IM. Overall, the results suggest that a large EBV type 1 load acquired during sexual intercourse can rapidly colonize the B cell population and induce the exaggerated T cell response that causes IM. Thus, IM could, perhaps, be prevented with a vaccine that reduces the viral load without necessarily inducing sterile immunity.

The Latent Membrane Protein 1 of Epstein-Barr Virus (EBV) Primes EBV Latency Cells for Type I Interferon Production

Epstein-Barr virus (EBV) latency has been associated with a variety of human cancers. Latent membrane protein 1 (LMP-1) is one of the key viral proteins required for transformation of primary B cells in vitro and establishment of EBV latency. We have previously shown that LMP-1 induces the expression of several interferon (IFN)-stimulated genes and has antiviral effect (Zhang, J., Das, S. C., Kotalik, C., Pattnaik, A. K., and Zhang, L. (2004) J. Biol. Chem. 279, 46335-46342). In this report, a novel mechanism related to the antiviral effect of LMP-1 is identified. We show that EBV type III latency cells, in which LMP-1 is expressed, are primed to produce robust levels of endogenous IFNs upon infection of Sendai virus. The priming action is due to the expression of LMP-1 but not EBV nuclear antigen 2 (EBNA-2). The signaling events from the C-terminal activator regions of LMP-1 are essential to prime cells for high IFN production. LMP-1-mediated activation of NF-kappaB is apparently necessary and sufficient for LMP-1-mediated priming effect in DG75 cells, a human B cell line. IFN regulatory factor 7 (IRF-7) that can be activated by LMP-1 is also implicated in the priming action. Taken together, these data strongly suggest that LMP-1 may prime EBV latency cells for IFN production and that the antiviral property of LMP-1 may be an intrinsic part of EBV latency program, which may assist the establishment and/or maintenance of viral latency.