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Quantitative analysis of cell-free Epstein-Barr virus DNA in plasma of patients with nonnasopharyngeal head and neck carcinomas.

PURPOSE: We investigated the detectability of EBV DNA in the plasma of patients with non-nasopharyngeal head and neck carcinomas (NNHNC). Previous studies have shown that EBV is present in the tumor tissue of some NNHNC. EXPERIMENTAL DESIGN: We recruited 101 patients with NNHNC and 48 healthy controls. Blood samples were taken from controls and patients before treatment. Tumor tissue samples were tested for the presence of EBV in the first 69 patients by in situ hybridization for small EBV-encoded RNA (EBER). Plasma EBV DNA was measured by real-time quantitative PCR in patients and controls. RESULTS: Squamous cell carcinoma (SCC) was the commonest histology (78 patients) followed by lymphoepithelial carcinoma (8 patients). EBER was detected in tumor cells in 7 of 69 patients tested. All of the EBER-positive tumors were lymphoepithelial carcinoma. Two controls (2 of 48; 4.2%) had detectable plasma EBV DNA. Plasma EBV DNA was detected in all of the patients with EBER-positive tumors, and in 23 of 94 (24.5%) patients with tumors of EBER-negative or unknown status. The proportion of plasma EBV DNA-positive cases in either group was significantly higher than that in the control group (P < 0.0027). Plasma EBV DNA concentrations in patients with EBER-positive tumors (median, 3827 copies/ml) were significantly higher than those in the controls (median, 0 copy/ml; P = 0.0001). Of patients with SCC, 21 (26.9%) had detectable plasma EBV DNA (median concentration, 34 copies/ml). Plasma EBV DNA concentrations in the whole group of patients with SCC (median, 0 copy/ml; interquartile range, 0-4 copies/ml) were also significantly higher than those in the controls (P = 0.001). CONCLUSIONS: Our data indicate that plasma EBV DNA reflects tumoral EBER status, and it may be of use as a tumor marker for EBER-positive NNHNC. The biological and clinical significance of low levels of circulating EBV DNA in the minority of patients with EBER-negative tumors remain to be elucidated.

Carcinoma, Squamous Cell↗

Expression of Epstein-Barr virus-encoded RNAs as a marker for metastatic undifferentiated nasopharyngeal carcinoma.

BACKGROUND: Epstein-Barr virus (EBV) is associated with undifferentiated nasopharyngeal carcinoma (NPC). EBV-encoded nonpolyadenlyated RNAs (EBERs) are often used as a marker to detect EBV-infected NPC cells. This study was conducted to document the expression and determine the significance of EBERs in NPC cells at various metastatic sites. METHODS: An in situ hybridization (ISH) technique was used to identify the presence of EBERs in paraffin embedded tissues of primary and metastatic sites obtained from 21 patients with NPC. Nineteen of these patients had undifferentiated lesions, and 2 had squamous cell carcinoma. One hundred and fifty specimens of normal tissues and tissues from patients with a variety of benign and malignant diseases other than NPC served as controls. In the NPC specimens, the expression of latent membrane protein (LMP) and a lytic protein, BZLF-1, were also examined by immunohistochemistry. RESULTS: Tissues from all patients with undifferentiated NPC and one patient with squamous cell carcinoma contained EBERs in the malignant cells; the other case of squamous cell carcinoma was negative. In metastatic NPCs, LMP was expressed in 18% (4 of 22) of tissues whereas BZLF-1 was not expressed in any tissues. EBERs were not detected in the 43 patients with normal tissues and benign lesions. In malignant diseases other than NPC, EBERs were detected in only 2 of 12 cases of non-Hodgkin's lymphoma, 1 of 2 cases of Hodgkin's lymphoma, and 1 of 6 cases of gastric cancer. CONCLUSIONS: By virtue of the direct correlation between latent EBV infection and NPC, the authors conclude that EBERs can be used as a sensitive marker to identify NPC cells at various metastatic sites by techniques of in situ hybridization, and that demonstration of EBERs in lesions of undifferentiated histology may be useful as a diagnostic adjunct for NPC presenting as metastatic cancer of unknown origin.

Biomarkers, Tumor↗

Association between Epstein-Barr virus and Burkitt's lymphoma in Taiwan.

BACKGROUND: The association between Epstein-Barr virus (EBV) and Burkitt's lymphoma (BL) in Taiwan is not clear. In this study, the authors attempted to determine the frequency of the occurrence of EBV infection in patients with BL in Taiwan. METHODS: A retrospective study was performed using a nonisotopic in situ hybridization technique to detect the presence of EBV-encoded small RNAs (EBERs) in paraffin embedded BL tissues. Tissues of other types of B-cell non-Hodgkin's lymphoma (NHL) were used as controls. Immunohistochemical staining was performed to examine the presence of an EBV-encoded protein, latent membrane protein (LMP), and p53 in specimens. RESULTS: EBERs were detectable in 10 of 18 BL specimens. It was present in the cervical lymph nodes (LNs) in six of the seven cases of cervical tumors, in the maxillary region in one case, in one of two cases of axillary LNs, and in the abdominal tumors in two of the seven cases of intraabdominal disease. EBER positive cells were diffusely present in all tumors except in one abdominal BL, in which only a few EBER positive cells were scattered in a small part of the tumor. EBER positive cells were not detected in the case with BL in an inguinal LN and in the seven cases with intraabdominal tumors. Immunohistochemical studies showed that LMP and p53 were expressed in 3 and 4 of the 18 cases, respectively. In another 20 NHLs in peripheral LNs, EBERs were detectable in only 1 case of diffuse large cell histology with numerous reactive T cells in which only large tumor cells expressed EBERs and LMP. EBERs were not detected in any of the ten cases of extranodal NHL. CONCLUSIONS: In Taiwan, EBV is frequently associated with BL occurring outside the abdomen but rarely with intraabdominal BL. The overall association between EBV and BL in Taiwan is intermediate compared with other regions of the world. These results support the theory that the frequency of EBV associated with BL is influenced by the endemicity of EBV and/or the socioeconomic status of a country.

Adolescent↗

EB virus-encoded RNAs are recognized by RIG-I and activate signaling to induce type I IFN.

Epstein-Barr virus (EBV)-encoded small RNAs (EBERs) are nonpolyadenylated, untranslated RNAs, exist most abundantly in latently EBV-infected cells, and are expected to show secondary structures with many short stem-loops. Retinoic acid-inducible gene I (RIG-I) is a cytosolic protein that detects viral double-stranded RNA (dsRNA) inside the cell and initiates signaling pathways leading to the induction of protective cellular genes, including type I interferons (IFNs). We investigated whether EBERs were recognized by RIG-I as dsRNA. Transfection of RIG-I plasmid induced IFNs and IFN-stimulated genes (ISGs) in EBV-positive Burkitt's lymphoma (BL) cells, but not in their EBV-negative counterparts or EBER-knockout EBV-infected BL cells. Transfection of EBER plasmid or in vitro-synthesized EBERs induced expression of type I IFNs and ISGs in RIG-I-expressing, EBV-negative BL cells, but not in RIG-I-minus counterparts. EBERs activated RIG-I's substrates, NF-kappaB and IFN regulatory factor 3, which were necessary for type I IFN activation. It was also shown that EBERs co-precipitated with RIG-I. These results indicate that EBERs are recognized by RIG-I and activate signaling to induce type I IFN in EBV-infected cells.

Base Sequence↗

Epstein-Barr virus in patients with chronic lymphocytic leukemia: a pilot study.

The objective of this study was to assess the incidence and the clinical significance of Epstein-Barr virus (EBV) in patients with chronic lymphocytic leukemia (CLL)/small lymphocytic lymphoma (SLL). Patients with CLL/SLL who presented at The University of Texas M. D. Anderson Cancer Center over a 2-year period and had available marrow paraffin blocks were studied for evidence of EBV infection using a highly specific in-situ hybridization assay for detection of EBV encoded RNA (EBERs). Results were analysed in relation to other presenting characteristics and outcome. Thirty-two patients were examined. EBERs were detected in the bone marrow of 12 of 32 (38%) CLL/SLL marrows vs 0 of 20 normal marrows (p = 0.002). EBERs were observed in sporadic granulocytes alone or in addition to its presence in lymphocytes in nine of the 12 EBV-positive patients. EBERs were detected less frequently in patients with Rai stage 0 - 1 disease (20%) compared with Rai stage 2 - 4 (66%; p = 0.008). EBER-positive patients tended to have higher lactate dehydrogenase levels (p = 0.053). The 10-year survival rate was 22% vs 58% for patients with and without discernible EBERs (log-rank, p = 0.08). Evidence of EBV infection was found in 38% of patients with CLL/SLL. Despite the small number of patients tested, discernable EBERs were significantly more common in individuals with more advanced Rai stage and there was a trend toward shorter survival in patients in whom EBV EBERs were discerned. Larger studies are needed to determine the prognostic value and role of EBV infection in patients with CLL/SLL.

Adult↗

Epstein-Barr virus-encoded poly(A)- RNA confers resistance to apoptosis mediated through Fas by blocking the PKR pathway in human epithelial intestine 407 cells.

Our recent findings demonstrated that the Epstein-Barr virus-encoding small nonpolyadenylated RNA (EBER) confers resistance to various apoptotic stimuli and contributes to the maintenance of malignant phenotypes in Burkitt's lymphoma. In this study we investigated the role of EBER in the human epithelial Intestine 407 cell line, which is known to be susceptible to Fas (Apo1/CD95)-mediated apoptosis. Fas, a member of the tumor necrosis factor receptor family, transduces extracellular signals to the apoptotic cellular machinery, leading to cell death. Transfection of the EBER gene into Intestine 407 cells significantly protected the cells from Fas-mediated apoptosis, whereas EBER-negative cell lines underwent apoptosis after Fas treatment. EBER bound double-stranded RNA-dependent protein kinase R (PKR), an interferon-inducible serine/threonine kinase, and abrogated its kinase activity. Moreover, expression of the catalytically inactive dominant-negative PKR provided resistance to Fas-induced apoptosis. Expression of EBER or dominant-negative PKR also inhibited the cleavage of poly(ADP-ribose) polymerase, a mediator of the cellular response to DNA damage, downstream of the Fas-mediated apoptotic pathway. These results in combination indicate that EBER confers resistance to Fas-mediated apoptosis by blocking PKR activity in Intestine 407 cells, consistent with the idea that EBER contributes to the maintenance of epithelioid malignancies.

Apoptosis↗

Striking similarities are exhibited by two small Epstein-Barr virus-encoded ribonucleic acids and the adenovirus-associated ribonucleic acids VAI and VAII.

The nucleotide sequence of the region of the Epstein-Barr virus genome that specifies two small ribonucleic acids (RNAs), EBER 1 and EBER 2, has been determined. Both of these RNAs are encoded by the right-hand 1,000 base pairs of the EcoRI J fragment of EBV deoxyribonucleic acid. EBER 1 is 166 (167) nucleotides long and EBER 2 is 172 +/- 1 nucleotides long; the heterogeneity resides at the 3' termini. The EBER genes are separated by 161 base pairs and are transcribed from the same deoxyribonucleic acid strand. In vitro, both EBER genes can be transcribed by RNA polymerase III; sequences homologous to previously identified RNA polymerase III intragenic transcription control regions are present. Striking similarities are therefore apparent both between the EBERs and the two adenovirus-associated RNAs, VAI and VAII, and between the regions of the two viral genomes that specify these small RNAs. We have shown that VAII RNA as well as VAI RNA and the EBERs exist in ribonucleoprotein complexes which are precipitable by anti-La antibodies associated with systemic lupus erythematosus. Finally, we have demonstrated that the binding of protein(s) from uninfected cells confers antigenicity on each of the four virus-encoded small RNAs.

Adenoviruses, Human↗

Prevalence of EBV RNA in sinonasal and Waldeyer's ring lymphomas.

A high incidence of a T cell phenotype of sinonasal lymphomas in other Asian countries has been associated with a high incidence of Epstein Barr virus (EBV) infection. We analyzed 13 sinonasal and 18 Waldeyer's ring lymphomas for the prevalence of EBV encoded RNA (EBER) using a sensitive and specific in situ hybridization. In addition, we examined the relationship of histologic findings and immunophenotype as well as the location of the lymphomas to the presence of EBV. The EBER was detected in each of 12 sinonasal lymphomas with a T cell immunophenotype. One B cell sinonasal lymphoma was EBER negative. Four of 18 Waldeyer's ring lymphomas were positive for EBER, including two T cell lymphomas. Two of 16 B cell Waldeyer's ring lymphomas were EBER positive. Morphologically, 11 of 20 diffuse large cell lymphomas, 2 diffuse mixed small and large cell lymphomas, 2 of 4 immunoblastic lymphomas and 1 lymphoplasmacytic lymphoma were EBER positive. Four follicular large cell lymphomas were EBER negative. A characteristic angiocentric or angiodestructive pattern was found in most T cell lymphomas and EBER positive cases. These findings indicate that EBV infection is more strongly associated with the T cell immunophenotype, angiocentric pattern and sinonasal location of the lymphoma.

Adult↗

Loss of p16 expression has prognostic significance in human nasopharyngeal carcinoma.

PURPOSE: p16 is an important inhibitor of cell cycle progression; absence of p16 can thus result in increased cellular proliferation. In nasopharyngeal carcinoma (NPC), absence of p16 has been reported in association with presence of the EBV and pRb. We therefore examined p16, pRb, and EBV-encoded RNA (EBER) expression in biopsy specimens from 84 patients with newly diagnosed NPC, who were treated primarily with curative radiation therapy. Our objective was to determine whether there was a correlation between these parameters and clinical outcome in NPC. EXPERIMENTAL DESIGN: Sections were cut from archival formalin-fixed, paraffin-embedded tumor blocks from NPC patients. p16 and pRb expression were determined using polyclonal and monoclonal antibodies, respectively. The presence of EBV was determined by in situ hybridization for EBER. The percentage of positively staining tumor nuclei was scored for p16 or pRb immunoreactivity. Relative intensity and proportion of cells with EBER signals were also documented. RESULTS: p16 expression was reduced (</=5% positive immunoexpression) in 59 of 84 (70%) NPC samples; in contrast, pRb was observed in all (100%) tumors. EBER signals were detected in 67 of 83 (81%) NPC specimens. There was a weak correlation between EBER presence and loss of p16 (P = 0.1). Using a Cox regression model controlling for known prognostic parameters, such as age, weight loss, and tumor stage, complete absence of p16 expression (0%, i.e., no immunostaining identified throughout the specimen) was associated with an inferior overall survival rate (P = 0.022). In addition, EBER-positive NPC was strongly associated with improved overall survival (P = 0.005) as reported previously (Shi et al., Cancer, 94: 1997, 2002). CONCLUSION: These results provide the first evidence suggesting that inactivation of p16 appears to be a significant predictor for poor overall survival in NPC. Given that reduced p16 expression is observed in the majority of patients with NPC, this indicates that therapeutic strategies targeting the p16 pathway may be a biologically rational approach for NPC. The favorable prognostic value of EBER suggests that future clinical trials with NPC should consider stratifying for EBER status.

Adult↗

Mucin and differentiation in Epstein-Barr virus-associated gastric carcinoma.

BACKGROUND/AIMS: Epstein-Barr virus (EBV) is present in roughly 1 in 10 cases of gastric carcinoma, particularly in undifferentiated adenocarcinomas. To clarify the histological developmental processes in EBV-associated gastric carcinoma, we investigated the presence of EBV infection, changes in the degree of differentiation within lesions, and mucin phenotypes of gastric carcinomas. METHODOLOGY: We had already examined 124 gastric carcinomas using in situ hybridization for EBV-encoded small RNA1 (EBER-1) and 12 lesions were EBER-1-positive. From these lesions we selected 8 carcinomas positive for EBER-1, and then chose 16 EBER-1-negative carcinomas as controls. Hematoxylin and eosin (H&E) stained specimens were examined for changes in histological type within each lesion. Mucin phenotypes of the specimens were determined using human gastric mucin (HGM), MUC2 and CD10 immunostaining. RESULTS: Of the EBER-1-positive lesions, 50% exhibited the gastric type mucin phenotype, whereas only 19% of the EBER-1-negative lesions were of the gastric phenotype. Changes in the histological type were seen within 75% of the EBER-1-positive lesions and within 62.5% of the EBER-1-negative lesions. CONCLUSIONS: The gastric mucin phenotype tended to be more common in the EBV-associated gastric carcinomas. The influence of EBV infection on the change in the histological type within the lesion was considered to be slight.

Adult↗

Epstein-Barr virus infection and its gene expression in gastric lymphoma of mucosa-associated lymphoid tissue.

The role of Epstein-Barr virus (EBV) in the pathogenesis of gastric lymphoma of mucosa-associated lymphoid tissue (MALT) has not been well understood. The aim of the study was to investigate EBV infection and its gene expression in this tumor in order to understand its role in the pathogenesis. EBV infection was screened by in situ hybridization for EBV-encoded non-polyadenylated RNA (EBER ISH) in 79 cases of gastric MALT lymphoma of nonimmunocompromised patients. The expression of EBV proteins [LMP1 (latent membrane protein 1), EBNA2 (EBV nuclear antigen 2), ZEBRA (switch protein encoded by BZLF1 gene)] was studied by immunohistochemistry in EBER-positive cases. EBV was detected with EBER ISH in 15 (19%) of the 79 cases. EBV was found in virtually all tumor cells in 2 cases of high-grade MALT lymphoma (2.5%) (EBV-associated), and was found only in occasional large or small lymphoid cells in 13 cases (16.5%). False positive EBER signal was detected in the mucinous glandular epithelial cells of gastric antrum with FITC-labeled oligonucleotide probe but not with digoxigenin or 35S-labeled riboprobes. Type II latency (EBER+LMP1+ EBNA2-) was detected in both EBV-associated cases. Type III latency (EBER+LMP1+EBNA2+) was also identified in one EBV-associated case besides latency II. Double labeling showed coexpression of LMP1 and EBNA2 in a small number of tumor cells, indicating the presence of type III latency in single cell level. In cases with only occasional EBER-positive large or small lymphoid cells, LMP1 and EBNA2 were not detected. ZEBRA was negative in all the cases. These findings suggest that EBV may contribute to the pathogenesis of a small proportion of high-grade MALT lymphoma, where virtually all tumor cells harbored EBV and the oncogenic viral protein LMP1 was expressed. Moreover, latency III of EBV infection may exist in nonimmunocompromised patient.

Animals↗

Localization of Epstein-Barr Virus-Encoded Small RNA-1 by in situ Reverse Transcription: Demonstration of cDNA Generation in Formalin-Fixed Paraffin-Embedded Tissue Sections.

Reverse transcription (RT) followed by polymerase chain reaction (RT-PCR) has been commonly used to detect viral and cellular transcripts in whole cell extracts. Application of this technique to tissue sections requires the in situ generation of cDNA. In this study, we selected an abundant transcript, Epstein-Barr virus (EBV)-encoded small RNA (EBER-1), as a model template to demonstrate cDNA generation in tissue sections. Using both digoxigenin-dUTP and primers which are complementary to EBER-1, we demonstrated specific EBER-1 cDNA generation both in vitro, and in tissue sections taken from formalin-fixed paraffin-embedded cell blocks of an EBV-infected cell line, B95-8. Furthermore, we utilized in situ RT in sections of EBV-associated nasopharyngeal carcinomas, and identified EBER-1 cDNA specifically in neoplastic cells, but not in the surrounding nonneoplastic stroma. EBER-1 cDNA was localized to the nucleus of these cells, with relative sparing of the nucleolus and the cytoplasm. No specific signal was evident if the reverse transcriptase was omitted, if 'sense' primers were used, or if RT was preceded by RNase digestion. The specificity of EBER-1 cDNA was further confirmed by in situ hybridization using the sense riboprobe, which has the same polarity as the EBER-1 transcript. Our results provide a successful example of using nonradioactive nucleotide analogue for cDNA generation in formalin-fixed, paraffin-embedded tissue sections. This approach would provide a visible assay to monitor RT in tissue sections, and allow further optimization of conditions for cDNA generation in tissue sections. Therefore, it potentially can be helpful for the future development of RT-PCR in tissue sections. Copyright 1995 S. Karger AG, Basel

Journal Article↗

Epstein-Barr virus infection to Epstein-Barr virus-negative nasopharyngeal carcinoma cell line TW03 enhances its tumorigenicity.

Almost all nasopharyngeal carcinomas (NPCs) are infected by Epstein-Barr virus (EBV), but most ex vivo NPC cells lose EBV genomes during passages. In this study, an EBV-negative NPC cell line, TW03, established from EBV-carrying NPC was reinfected with EBV by cocultivation with irradiated Akata cells carrying recombinant EBV containing a neomycin-resistant gene. The reinfected EBV (+) TW03 cells expressed EBERs and EBNA1, but not EBNA2, lytic proteins (ZEBRA and EA-D), or LMP1. They had an epithelial appearance similar to that of EBV (-) TW03 cells. The doubling times of EBV (+) and EBV (-) TW03 cells were almost identical. However, the EBV (+) TW03 cells formed larger colonies with ragged contours in anchorage-independent cultures. An in vitro invasion assay showed that EBV (+) TW03 cells had a higher invasive activity than EBV (-) TW03 cells (p < 0.01). Both EBV (-) and EBV (+) TW03 cells formed poorly differentiated squamous cell carcinomas in SCID and nude mice. EBV (+) TW03 cells showed a higher tumorigenicity to nude mice (12 of 13) than EBV (-) TW03 cells (1 of 9) (p < 0.001). In the severe combined immunodeficiency (SCID) tumors of EBV (+) TW03 cells, not all of the tumor cells were EBER-1 positive. EBER-1 was more frequently detected in the peripheral regions and daughter nodules of the tumors than in the central areas. The microdissection polymerase chain reaction showed that the EBER-1-negative TW03 cells in the EBV (+) TW03 SCID tumors lost EBV genomes. EBER-1-negative cells showed as high a rate of Ki-67 positivity as EBER-1-positive cells, indicating that the former were proliferating rather than dead or dying. In horny pearls, keratinizing cells were ZEBRA-positive and EBER-negative. Loss of EBV genomes was not associated with squamous differentiation. These data indicated that reinfection of EBV promotes the tumorigenicity of EBV (-) TW03 cells by enhancing the invading activity.

Animals↗

Epstein-Barr virus and gastric carcinoma in Western patients: comparison of pathological parameters and p53 expression in EBV-positive and negative tumours.

AIMS: The presence of Epstein-Barr virus (EBV) was studied in 56 gastric carcinomas from Western patients by in-situ hybridization for EBV-encoded RNAs (EBER). EBV-positive and negative carcinomas were compared for various pathological parameters including p53 overexpression. METHODS AND RESULTS: EBERs transcripts were detected in seven cases overall: four cases of 52 conventional carcinomas (7. 7%) and three cases of four gastric carcinomas with lymphoid stroma (75%). EBER positivity was diffuse in five cases and restricted to a localized area of the tumour in two cases of conventional carcinoma. A monoclonal EBV genomic pattern was demonstrated in the case tested by Southern blot analysis. By immunohistochemical analysis, neither EBV latent or lytic cycle proteins nor C3d/EBV receptor were expressed by neoplastic cells. EBER positivity was significantly correlated with prominent lymphoid reaction (P = 0.0002) which was associated with numerous PS100-positive dendritic cells and with HLA-DR expression by tumour cells (P = 0.03). p53 immunoreactivity in more than 30% of tumour cells was detected in 25 out 49 EBV-negative cases and was absent in EBV-positive cases except in one case with focal EBER-positivity. CONCLUSIONS: Focal staining for EBER is an unusual finding in the setting of gastric carcinoma and these results suggest that there might be two types of EBV-associated gastric carcinoma in which the viral infection will play a different role. The presence of a stromal lymphoid reaction which is strongly correlated with EBV positivity, is associated with antigen-presenting ability by HLA-DR-positive tumour cells or abundant dendritic cells. The function of p53 appears preserved in all EBV-associated carcinomas except in one case with focal EBER expression whereas the immunohistochemical pattern of p53 is suggestive of a mutational phenomenon in 51% of EBV-negative cases.

Female↗

Epstein-Barr virus latency in kidney specimens from transplant recipients.

BACKGROUND: Epstein-Barr virus (EBV) infection is common in immunosuppressed patients and can lead to life threatening lymphoproliferative diseases. Small numbers of cells infected by EBV have been detected in human tissues, transplanted or non-transplanted. Little is known about EBV latency in the allograft kidneys of patients without post-transplant lymphoproliferative disease (PTLD). The aims of this study were to look for the presence of EBV-encoded small RNAs (EBER) in allograft kidneys and to quantify their expression. METHODS: We analysed 62 allograft nephrectomies and 20 native kidneys to determine the presence of EBV; we also quantified its expression and calculated its ratios to CD45 and CD20 cells. The techniques used were: tissue microarray, EBER-1- and 2-specific in situ hybridization and immunohistochemistry. RESULTS: EBER expression was detected in 30.6% of transplanted kidneys and 5% of non-transplanted kidneys. In the positive specimens, a mean of 8.2 cells/1.57 mm(2) expressed the EBERs (range 1-38 cells). The ratios of EBER-positive (+) cells to CD45 or CD20 cells were 1.7 +/- 2.4% (range 0.1-8.1%) and 8.4 +/- 10.9% (range 0.5-34.4%), respectively. No relationship was found between anti-T-cell treatment and EBER expression in the failed allografts. CONCLUSIONS: In failed kidney allografts, a small number of lymphocytes can express EBV latency. The number of EBER+ cells is smaller than in PTLD. Studies of functioning grafts are necessary to better understand the clinical relevance of this expression.

Adult↗

Detection of Epstein-Barr viral RNA in malignant lymphomas of the upper aerodigestive tract.

Recent studies have suggested a probable etiologic association between Epstein-Barr virus (EBV) and nasal lymphomas, irrespective of geographic location. This study was performed to investigate the strength of association of EBV with non-Hodgkin's lymphomas of the upper aerodigestive tract, based on a large series of cases that have been thoroughly immunophenotyped on frozen tissues. A sensitive in situ hybridization technique was used to detect EBV encoded RNA (EBER) in paraffin sections. Among 30 cases of nasal/nasopharyngeal T-cell lymphoma, 25 (83.3%) were EBER-positive. In the positive cases, most of the neoplastic cells showed strong nuclear signals. Further analysis of this group of tumors showed that all 21 cases (100%) with a CD56+ CD3-phenotype were EBER positive, whereas four of nine cases (44.4%) with a CD56-negative immunophenotype were positive. Only one of 10 cases (10%) of nasal/nasopharyngeal B-cell lymphoma was EBER positive; the positive case was a diffuse mixed-cell lymphoma and could not be distinguished morphologically from the negative cases. Among the 21 cases of lymphoma of the tonsils and back of the tongue (20 B-lineage and one T-lineage), none was EBER positive. In the normal mucosa of the nose/nasopharynx or tonsil (20 cases studied), only very rare EBER-positive small lymphocytes were found in two cases. The almost exclusive detection of EBER in nasal/nasopharyngeal T-cell neoplasms among the lymphomas of the upper aerodigestive tract suggests that EBV probably plays an etiologic role in the pathogenesis of this group of tumors and is not simply a passenger virus, and neither is this merely a site-dependent phenomenon in view of the weak association with nasal/nasopharyngeal B-cell lymphoma.

Herpesvirus 4, Human↗

Distribution of Epstein-Barr virus in systemic rheumatic disease (rheumatoid arthritis, systemic lupus erythematosus, dermatomyositis) with associated lymphadenopathy: a study of 49 cases.

Among systemic rheumatic diseases (SRDs), lymphadenopathy is frequently found in patients with rheumatoid arthritis (RA) and systemic lupus erythematous (SLE). Epstein-Barr virus (EBV)-associated lymphoproliferative disorders (LPDs) may occur in patients following methotrexate therapy for RA and dermatomyositis (DM). However, little is known about the distribution of EBV in reactive LPDs in patients with SRDs who had no history of methotrexate therapy. We analyzed 49 such patients (SLE=25, RA=23, DM=1) for the presence and distribution of EBV+ cells using Epstein-Barr virus (EBV)-encoded small RNA (EBER) specific in situ hybridization. A positive signal for EBERs was identified in 9 (SLE=5, RA=4) (18%) of 49 cases, and 3 main distribution patterns of EBER+cells could be delineated: pattern A, more than 500 EBER-positive cells were located in the germinal centers as well as interfollicular area (SLE=2); pattern B, EBER + cells were located in a few germinal centers (RA=2); and pattern C, up to 100 EBER+ cells were located in the interfollicular area (SLE=3, RA=2). Recent EBV infection may be a cause of lymph node lesion in only 2 cases of patients with pattern A. However, the pathognomonic significance of pattern B and pattern C EBER + cell distribution patterns still remains unclear. Our study indicates that the underlying immune deficits of patients with SRDs may also play an important role in the development of EBV-associated LPDs in SRDs, as previously suggested by several authors.

Adult↗

Circulating Epstein-Barr virus DNA in the serum of patients with gastric carcinoma.

PURPOSE: We investigated the detectability of EBV DNA in the serum of gastric carcinoma patients in Hong Kong. Previous data have shown that approximately 10% of gastric carcinomas in Hong Kong are associated with EBV. EXPERIMENTAL DESIGN: We recruited 51 patients with gastric carcinoma, 30 patients with gastritis, and 197 apparently healthy controls. For gastric carcinoma patients, blood samples were obtained before surgery. After surgery, the resected tumor samples from the cancer cases were subjected to in situ hybridization for small EBV-encoded RNA (EBER). Serum EBV DNA in all cases was measured by real-time quantitative PCR. RESULTS: Serum EBV DNA was detectable in 5 of 5 (100%) EBER-positive gastric carcinoma cases (median concentration, 1063 copies/ml), in 13 of 14 (93%) EBER-negative gastric carcinoma cases with EBER-positive infiltrating lymphocytes (median concentration, 50 copies/ml), and in 0 of 32 (0%) EBER-negative cases. In the nontumor controls, serum EBV DNA was detectable in 7 of 30 (23%) gastritis cases (median concentration, 0 copies/ml) and in 7 of 197 (3.6%) apparently healthy individuals (median concentration, 0 copy/ml). CONCLUSIONS: Our data indicate that serum EBV DNA reflects tumoral EBER status and opens up the possibility that circulating EBV DNA may be used as a tumor marker for the EBER-positive gastric carcinomas. The biological and clinical significance of the presence of low levels of circulating EBV DNA in the minority of gastritis patients and healthy individuals remains to be elucidated.

DNA, Viral↗