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At least 109 records · Page 6Linked to original sources
PubMed2004

[Malignant transformation of a human oral squamous cell carcinoma cell strain OSC-19 by EBV encoded small RNAs].

OBJECTIVE: To observe the growth characteristics of the EBERs-transfected OSC (oral squamous carcinoma)-19 cells, through generated overexpression of EBERs in OSC-19 cells. METHOD: EBERs fragment were amplified by PCR from EBV-positive NPC-KT cell DNA. Using molecular biologic technique, we constructed the EBERs-expressing plasmids, which contained, 4 or 10 tandem repeats of the EBERs. The OSC-19 cells were transfected with those plasmids, respectively. We demenstrated the overexpression of EBERs in EBERs-transfected OSC-19 cells by Northern Blot analysis, and compared the growth characteristics in culture and colony formation in soft agar of Hygr- and EBERs-transfected OSC-19 cells. RESULT: 10EBERs-transfected OSC-19 cells lost cell-to-cell contacts and acquired long spindle-shape morphology in culture and formed colonies in soft agar. However, parental and Hygr-transfected OSC-19 cells scarcely did. CONCLUSION: In this study, we established 10 EBERs-transfected OSC-19 cells, which overexpressing the EBERs and showed that it has a scattering activity in culture and a role in anchorage-independent growth in soft agar. These results indicate that EBERs has a role of malignant transformation in OSC-19 cells. However, the 10 EBERs-transfected OSC-19 cell provides a useful epithelial model for studying the function of EBERs.

Carcinoma, Squamous Cell↗
PubMed1998

Frequent detection of Epstein-Barr virus-infected B cells in peripheral T-cell lymphomas.

Although Epstein-Barr virus (EBV) positivity has been described in peripheral T-cell lymphomas (PTCLs) in Chinese patients, the cellular lineage of EBV-harbouring cells is unknown. Forty-four cases of PTCL were therefore studied by in situ hybridization (ISH) for EBV-encoded small non-polyadenylated RNA 1 and 2 (EBER), and the lineage of the EBER+ cells was determined by double labelling. The findings were further correlated with the clonality of EBV and the genotype of these EBER+ tumours. The results for the detection of EBV by ISH show that 23 of the 44 cases were EBER+. In 5/23 of the EBER+ cases, EBER was found in around 50 per cent of atypical cells and in 18/23 cases, EBER was found in a subpopulation of atypical cells. Among the EBER+ cases, all 15 tested showed clonal T-cell receptor gene rearrangement by Southern blot hybridization. Double labelling was successfully done in 11 EBER+ cases, and by comparison, EBER+/CD20+ B cells outnumbered the EBER+/CD3+ T cells in all these cases. EBV clonality analysis revealed that EBV was monoclonal in six EBER+ cases and biclonal in three cases. With the predominance of EBV+ B cells over EBV+ neoplastic T cells being observed in most of these cases, it is possible that the EBV-infected clonal population may be of B-cell lineage. This was supported in some cases where a faint clonal band was seen over a background smear in the gene rearrangement study of immunoglobulin heavy chain gene by polymerase chain reaction (PCR), indicating a minor B-cell clone. It is concluded that in EBV+ PTCL, EBV is preferentially localized in B cells rather than neoplastic T cells. The neoplastic T cells may support the clonal proliferation of a subpopulation of EBV+ B cells in PTCLs.

B-Lymphocytes↗
PubMed1997

Epstein-Barr virus-associated primary gastrointestinal lymphoma in non-immunocompromised patients in Korea.

We examined 81 cases of primary gastrointestinal lymphomas in Korea, including 64 gastric lymphomas and 17 intestinal lymphomas, for EBV expression by EBER-1 in situ hybridization (ISH) and EBNA-1 PCR. In EBER-1 positive cases, we performed immunohistochemistry for latent membrane protein-1 (LMP-1) and EBV diffuse early antigen (EA(D)) to compare EBV latent gene expression and lytic process. EBER-1 was detected in 15 of 81 cases of lymphomas. EBER-1 expression showed three different patterns on tumour cells; diffuse 4/81 (5%), localized 4/81 (8%), and a few scattered pattern 7/81 (9%). We regarded diffuse pattern and localized pattern as EBER-1 positive group (8/81: 10%). Diffuse pattern of EBER-1 was shown in all three T-cell lymphomas and one B-cell lymphoma. A localized pattern was seen all in B-cell lymphomas. The EBER-1 expression was 11% in the stomach (7/64) and 6% in the intestine (1/17). Five of the eight EBER-1 positive gastric lymphomas were histologically diffuse large B-cell lymphomas, and the other three were peripheral T-cell lymphoma, unspecified, one angiocentric lymphoma, and one intestinal T-cell lymphoma by REAL classification. Eight MALT type gastric B-cell lymphomas showed no EBV association. EBV nuclear antigen (EBNA-1) was detected in 15 of 45 resected cases (33%) by PCR. EBER-1 positive cases were all EBNA-1 positive. Twelve EBNA-positive/EBER-negative cases consisted of seven cases showing a few scattered EBER-1 positive lymphocytes. LMP-1 and diffuse early antigen (EA(D)) was detected in five and three cases, respectively. Although follow-up information in our series was incomplete, it seemed that there was no significant difference in their staging or prognosis between EBER-positive cases and EBER-negative group. It is concluded that EBV is associated with some lymphomas among Koreans without overt pre-existing immunodeficiency, especially in T-cell lymphomas.

Adolescent↗
PubMed1996

Epstein-Barr virus genome in non-Hodgkin's lymphomas occurring in immunocompetent patients: highest prevalence in nonlymphoblastic T-cell lymphoma and correlation with a poor prognosis. Danish Lymphoma Study Group, LYFO.

A series of 520 cases of non-Hodgkin's lymphoma (NHL; 374 of B-cell, 130 of T-cell, 5 of non-B/non-T-cell, and 11 of undetermined phenotype) was analyzed for the presence of Epstein-Barr virus (EBV) using RNA in situ hybridization (RISH). The aims of the study were to assess the frequency of EBV-encoded small nuclear RNAs 1 and 2 (EBER), abundant immediate early RNAs (BHLF), and latent membrane protein-1 (LMP-1) in cases covering the entire histologic spectrum of NHL, and to analyze whether EBV status had prognostic relevance with regard to patient survival. EBER positivity was found in 25 of 374 (7%) B-NHL and 40 of 130 (31%) T-NHL (P < .00005) cases, but in only 1 of 16 cases with non-B/non-T-cell or undetermined phenotype. Among T-NHL cases, EBER positivity was confined to angioimmunoblastic, lymphadenopathy-like lymphoma (11 of 13 cases, 85%), Lennert's lymphoma (five of seven cases, 71%), and pleomorphic T-NHL (24 of 67 cases, 36%). Mycosis fungoides, lymphoblastic, and CD30-positive anaplastic large T-cell NHL cases were consistently EBV-negative. Double-labeling by RISH and immunophenotyping demonstrated the presence of EBV in neoplastic T cells, but no CD21 expression was found in the EBER-positive T-NHL cases. LMP-1 was expressed in 12 of 40 (30%) EBER-positive T-NHL and 5 of 25 (20%) EBER-positive B-NHL cases. For both T- and B-NHL, no correlation was found for EBER positivity and age, sex, clinical stage, or serum level of lactate dehydrogenase (LDH) at diagnosis. However, in T-NHL but not B-NHL, EBER positivity correlated with the presence of constitutional symptoms and a poor performance score (PS < 1; scale, 0 to 4). EBER status did not have any prognostic significance in B-NHL, but it had a negative prognostic impact in high-grade T-NHL (7-year survival of EBER-negative v EBER-positive cases: 33% v 14%; P = .01). A multivariate analysis including all B- and T-NHL of intermediate-/high-grade histology showed that EBER positivity in T-NHL was one of the three most significant factors recognized by the final prognostic model, only surpassed by PS greater than 1 and age greater than 67 years, and more powerful than B symptoms, an elevated LDH, or disseminated disease (clinical stage greater than II). We conclude that patients with EBV-positive T-NHL have a very poor clinical outcome, that EBV status should be considered as additional useful information in the classification of T-NHL, and that EBV-positive T-NHL should be treated as a separate entity in the future.

Adolescent↗
PubMed2005

Critical role of Epstein-Barr Virus (EBV)-encoded RNA in efficient EBV-induced B-lymphocyte growth transformation.

It was demonstrated that Epstein-Barr virus (EBV)-encoded small RNAs (EBERs) were nonessential for B-lymphocyte growth transformation. We revisited this issue by producing a large quantity of EBER-deleted EBV by using an Akata cell system. Although the EBER-deleted virus efficiently infected B lymphocytes, its 50% transforming dose was approximately 100-fold less than that of the EBER-positive EBV. We then engineered the genome of EBER-deleted virus and generated a recombinant virus with the EBER genes reconstituted at their native locus. The resultant EBER-reconstituted EBV exhibited restored transforming ability. In addition, lymphoblastoid cell lines established with the EBER-deleted EBV grew significantly more slowly than those established with wild-type or EBER-reconstituted EBV, and the difference between the growth rates was especially highlighted when the cells were plated at low cell densities. These results clearly demonstrate that EBERs significantly contribute to the efficient growth transformation of B lymphocytes by enhancing the growth potential of transformed lymphocytes.

B-Lymphocytes↗
PubMed2000

Clinicopathological analyses of 5 Japanese patients with CD56+ primary cutaneous lymphomas.

We analyzed the clinicopathological features of 5 Japanese patients with CD56+ primary cutaneous lymphomas (3 men and 2 women aged 25 to 73 years). Except for 1 patient in whom bone marrow involvement was simultaneously observed, all patients presented with cutaneous lesions. Based on their Epstein-Barr virus (EBV) status, we categorized these patients into 2 groups, namely EBV-encoded small RNA-1 (EBER-1) (3 patients) and EBER-1- (2 patients). Generalized lymphadenopathy and bone marrow involvement were observed only in EBER-1 patients. Morphologically, angiocentric proliferation was more prominent in EBER-1+ patients and was accompanied by panniculitis-like changes. The lymphomas in EBER-1- patients featured monomorphic proliferation of lymphoblastic cells with no cytoplasmic granules. Phenotypically, CD3-, cytoplasmic CD3 epsilon+, and CD56+ were common findings in both types. The EBER-1- type showed an additional distinguishing feature, CD7+, CD4+, CD8-, HLA-DR+, and terminal deoxynucleotidyl transferase-positive (TdT+) phenotype. The lymphoma was primarily resistant in the EBER-1+ type, and the patients died within 6 months of admission. In contrast, the lymphoma in the EBER-1- patients was originally chemosensitive. Collectively, we consider there to be at least 2 types of CD56+ primary cutaneous lymphomas, corresponding to nasal-type natural killer (NK)/T-cell lymphomas (EBER-1+) and blastic NK-cell lymphomas (EBER-1-).

Adult↗
PubMed2002

Prognostic significance of Epstein-Barr virus involvement in gastric carcinoma in Japan.

We examined the prognosis of 64 EBV-associated gastric carcinoma (EBV-GC) cases and 128 EBV-negative gastric carcinoma cases. EBV-GCs were identified by detecting EBV-encoded small RNA (EBER) using in situ hybridization assay of paraffin-embedded tissue. For each EBV-GC case, 2 EBER-negative cases (EBV-negative cases) were selected, matching the EBV-GC case with respect to age, sex, tumor location, and depth of invasion. The average follow-up period was 70.9 months (SD=61.1) in EBV-GCs and 63.8 months (SD=59.7) in EBV-negative cases. Tumor-advanced stage determined by TNM classification of UICC, tumor location, and p53 over-expression were statistically significant prognostic factors. On the other hand, EBER expression was not related to the survival of patients. However, further analysis specific for intestinal and diffuse types of Lauren classification revealed that the association of EBER expression with prognosis was different in the two histological types. EBER expression was related to poor prognosis in intestinal-type carcinoma [hazard ratio (HR) =2.5, 95% confidence intervals (CI) =1.3-4.8] after adjusting for stage, p53 over-expression, and tumor location, whereas the diffuse-type EBV-GC had better prognosis (HR=0.4, 95% CI=0.2-0.9) even when lymphoepithelioma-like carcinomas were excluded. To examine the interactive prognostic effects between EBER expression and p53 over-expression, the study subjects were divided into 4 groups on the basis of EBER expression and p53 over-expression. In intestinal-type tumors, the cases having both EBER expression and p53 over-expression showed the poorest prognosis (HR=10.0, 95% CI=3.3-30.4), and the cases with either EBER expression or p53 over-expression had an intermediate prognosis. In diffuse-type tumor, only EBER was an important prognostic factor. These results give additional evidence implicating EBV in the natural history of EBV-GCs.

Epstein-Barr Virus Infections↗
PubMed2005

Bone marrow that is positive for Epstein-Barr virus encoded RNA-1 by in situ hybridization is related with a poor prognosis in patients with extranodal natural killer/T-cell lymphoma, nasal type.

BACKGROUND AND OBJECTIVES: Extranodal NK/T-cell lymphoma, nasal type is an aggressive lymphoma that is always associated with Epstein-Barr virus (EBV). This study was done to evaluate the use of EBV-encoded RNA-1 in situ hybridization (EBER-1 ISH) to detect occult micrometastasis in the bone marrow (BM) of patients with nasal NK/T-cell lymphoma. DESIGN AND METHODS: A total of 23 patients who underwent BM biopsy for routine pre-therapeutic evaluation were enrolled in the study. We used EBER-1 ISH to investigate the expression of EBER-1 in 30 BM specimens. The clinical correlation and therapeutic outcomes of these patients were analyzed. In addition, genomic analysis of EBV was performed in five patients. RESULTS: Conventional morphologic examinations failed to identify any lymphoma involvement in the 23 BM specimens obtained at initial staging. However, 10 of the 23 BM were positive for EBER-1. A lower survival rate was seen in patients with BM positive for EBER-1. Only the BM EBER-1 ISH result was shown to be an independent variable predicting overall survival in stage I and II patients (p=0.027; hazard ratio for death 0.066, 95% confidence interval, 0.006 to 0.733), suggesting that EBER-1 positivity in BM is the major determinant of a poor prognosis. However, discrepancies in the EBV strains between the primary tumor and BM existed in two of the five studied patients. INTERPRETATION AND CONCLUSIONS: We suggest that EBER-1 ISH should be performed on BM specimens of patients with nasal NK/T-cell lymphoma to identify the presence of EBER-1 positive cells, which appears to carry a poor prognosis. Whether or not the EBER-1 positive cells in the BM of nasal NK/T-cell lymphoma patients are true tumor cells requires further study.

Adult↗
PubMed1994

In situ localization of Epstein-Barr virus encoded RNA in non-nasal/nasopharyngeal CD56-positive and CD56-negative T-cell lymphomas.

We recently reported a group of non-nasal/nasopharyngeal hematolymphoid malignancies expressing the natural killer cell marker CD56, characterized by frequent extranodal localization, angiocentricity, and aggressive clinical course (HUM PATHOL 23:798-804, 1992). Because we have shown a very strong association of Epstein-Barr virus (EBV) with CD56-positive T-cell lymphomas of the nose nasopharynx, we asked whether a similar association also occurs with the non-nasal CD56-positive T-cell lymphomas. In situ localization of EBV encoded RNA (EBER) was performed on paraffin sections of 15 such cases, including the nine previously reported cases and six new cases (three showing prominent hepatosplenic involvement and three showing involvement of one or more extranodal sites, such as the parotid gland, tonsils, gastrointestinal tract, skeletal muscle, and testis). A case was considered positive when the majority of the tumor cells showed nuclear signal. Ten cases showed EBER positivity, and all but one of them were negative for CD3 and other T-cell markers, except CD2. Only one of four cases showing a CD3-positive phenotype was EBER positive. Of the remaining two CD3-negative EBER-negative cases, one showed a histiocytic phenotype and the other was positive for multiple T-cell markers. Among 15 cases of CD56-negative non-nasal peripheral T-cell lymphoma studied for comparison, six were CD3-negative, among which three showed EBER positivity. All nine CD3-positive cases were EBER negative. Five cases (three CD3 positive and two CD3 negative) showed rare isolated (< 1%) EBER-positive tumor cells. We conclude that among non-nasal T-cell lymphomas, EBV is strongly correlated with CD56 positivity (66.7% v 20%), and the positive cases almost always show an immunophenotype identical to that commonly observed in nasal lymphomas (CD2 positive, CD3 negative, and CD56 positive). Thus, EBV may play an etiologic role in these CD56-positive lymphomas. There is also a correlation between EBER positivity and CD3 negativity, irrespective of the CD56 status. The presence of isolated EBER-positive cells in CD56-negative T-cell lymphomas, occurring at a frequency similar to that reported in the European population, probably represents secondary infection of tumor cells.

Adult↗
PubMed1993

Detection of Epstein-Barr virus nucleic acid sequences and protein in nodal T-cell lymphomas: relation between latent membrane protein-1 positivity and clinical course.

Forty-six nodal T-cell lymphomas, classified according to the updated Kiel classification, were investigated for the presence of Epstein-Barr virus (EBV) DNA by polymerase chain reaction (PCR), EBER 1 and 2 (EBER 1/2) and latent membrane protein-1 (LMP-1) expression. A combination of RNA in situ hybridization and immunohistochemistry was used to establish the phenotype of the Epstein-Barr virus harbouring cells. In 21 of 45 cases Epstein-Barr virus DNA sequences could be detected with the polymerase chain reaction. In 15 cases (14 of 21 EBV PCR positive cases), EBER 1/2 positive cells could be demonstrated. As judged by morphology, EBER 1/2 expression was found in nonneoplastic and neoplastic lymphoid cells. Double staining revealed that more than 80% of the EBER 1/2 harbouring cells, lacked B-, T- or histiocytic markers, suggesting down regulation of T- and B-cell markers by Epstein-Barr virus. In eight of 15 cases some EBER 1/2 positive T-cells (CD3, CD45RO, CD43) morphologically resembling tumour cells were found. In nine of 14 cases tested EBER 1/2 positive non-neoplastic B-cells (CD20) were seen. Based on in situ hybridization results, four patterns of EBER 1/2 positive cells were found, i.e. single cells (< 1 per medium power field (mpf), n = 3), scattered (1-25/mpf, n = 4), clustered (26-100/mpf, n = 5) and diffuse (> 100/mpf, n = 3). In eight of 15 cases a clustered or diffuse pattern of EBER 1/2 positive cells was found and these lymphomas were therefore considered to be strongly associated with Epstein-Barr virus. In these lymphomas LMP-1 expression was found to be associated with an aggressive clinical course and hepatosplenomegaly.

Herpesvirus 4, Human↗