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Query: UMLS:C0079731 (B-cell lymphoma)
 16,671 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Epstein-Barr virus is an important aetiological factor in certain HIV-related syndromes, with its opportunist expression related to the level of host immunodeficiency. In asymptomatic people co-infected with HIV, EBV activity is reflected by increased viral shedding and rises in anti-EBV titres; as immunodeficiency ensues EBV manifests as epithelial hyperproliferation in OHL, and later as B-cell lymphoma in AIDS. The suggested role of EBV as a co-factor in the progression of HIV infection and development of AIDS has not been established, although another herpesvirus, cytomegalovirus, might play such a role. Advances in our understanding of HIV regulation and its interaction with other latent (herpes) viruses should provide important molecular and pharmacological approaches to the clinical management of advanced HIV disease.
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PMID:Acquired immunodeficiency syndrome and Epstein-Barr virus. 196 85

109 malignant lymphomas were surveyed by Southern blot analysis and polymerase chain reaction (PCR) for Epstein-Barr virus (EBV) DNA and compared with 16 examples of non-neoplastic lymphadenopathy and 4 normal thymuses. In specimens positive by the method of Southern and PCR, in situ hybridization studies were performed on formalin-fixed, paraffin-embedded sections. By Southern blot analysis, two of seven Hodgkin's disease samples (29%) (one of mixed cellularity and the other of lymphocyte predominance type), three of 56 B-cell lymphomas (5.6%) and five of 46 T-cell lymphomas (11%) demonstrated EBV DNA. However, the 16 examples of lymphadenitis and the 4 normal thymuses showed no EBV DNA. With PCR, EBV DNA was identified in one B-cell lymphoma, nine T-cell lymphomas, ten lymphadenitis specimens and two of the normal thymus, in addition to the positive specimens determined by the Southern blotting method. These results indicate that the presence of EBV DNA is not related to lymphoid malignancy, but enhancement of the DNA is demonstrated in some neoplastic conditions. By in situ hybridization, EBV genomes were not detected in all PCR-positive cases, but only in those positive by Southern blot analysis.
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PMID:Analysis of Epstein-Barr viral genomes in lymphoid malignancy using Southern blotting, polymerase chain reaction and in situ hybridization. 198 7

The pathogenesis of non-Hodgkin's lymphoma (NHL) in HIV-infected individuals is currently poorly understood; however, recent molecular studies have subdivided these lymphomas into distinct molecular pathologic entities. Similar to endemic and sporadic Burkitt's lymphoma, monoclonal B-lymphoma subsets were found to be infected with Epstein-Barr virus (EBV) or have c-myc gene rearrangements, suggesting a role for EBV infection or chromosomal translocation in a subset of AIDS NHLs. Similar to lymphomas that occur in immunosuppressed transplant patients, EBV-positive polyclonal lymphomas also have been described. Unique to HIV-infected patients, however, is the subset of polyclonal B-cell lymphoma with no evidence for EBV infection. Based on these molecular studies, it is apparent that the AIDS NHLs represent a heterogeneous set of diseases with a number of pathogenic processes involved in lymphomagenesis.
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PMID:Molecular pathogenesis of AIDS-associated non-Hodgkin's lymphoma. 202 96

By in vitro transformation with Epstein-Barr virus (EBV), we have previously established EBV+ lymphoblastoid cell lines (LCL) from a patient with leukemic centrocytic B cell lymphoma. EBV-transformed LCL and EBV genome-negative leukemic B cells showed identical chromosome aberrations and IgH gene rearrangements. In the present study we have analyzed the effect of exogenous cytokines [interleukin (IL) 1, 2, 3, 4, 6, tumor necrosis factor, lymphotoxin, transforming growth factor beta, (TGF-beta)] and anti-IgM antibodies on the in vitro proliferation of EBV- leukemic B cells and EBV-converted LCL. In contrast to conventional chronic lymphocytic leukemia, B cells of the patient DUL spontaneously proliferated for up to two weeks in the absence of exogenous lymphokines. The spontaneous proliferative capacity of clonal DUL B cells was not modulated by IL 1, IL 3, IL 6, TNF or LT. In vitro growth of DUL B cells was increased, however, by exogenous recombinant (r)IL 2, and was abrogated by TGF-beta, rIL 4 and anti-IgM. rIL 4 not only inhibited spontaneous B cell proliferation but also neutralized the enhancing effect of rIL 2. In contrast, growth of the EBV-transformed DUL LCL was not affected by any of these factors. These data demonstrate that in vitro infection and transformation of a clonal B cell population by EBV induces a switch in responsiveness to rIL 4, TGF-beta and anti-IgM. In addition, this report is the first to demonstrate an inhibitory effect of rIL 4 on a spontaneously proliferating human leukemic B cell clone.
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PMID:In vitro transformation by Epstein-Barr virus induces a switch in growth factor and anti-IgM responsiveness in a human leukemic B cell clone. 215 17

Polymorphic B-cell lymphoma seen in four patients with congenital immunodeficiencies and in two patients with leukemia receiving chemotherapy was associated with the Epstein-Barr virus (EBV). The tumors had characteristic histologic features: they were polymorphic consisting of a mixture of lymphoblasts and differentiated cells including plasma cells, and areas of hemorrhagic necrosis were prominent. The tumors were either polyclonal, monoclonal, or multiclonal. Patients with congenital immunodeficiencies who developed these tumors died despite radiotherapy, corticosteroids plus acyclovir, or a combination of intravenous (IV) immunoglobulins and alpha 2 interferon. Patients with leukemia recovered when immunosuppressive drugs were discontinued and leukemia has not recurred over a period of 2 and 4 years, respectively, in the two patients.
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PMID:Epstein-Barr virus polymorphic B-cell lymphoma associated with leukemia and with congenital immunodeficiencies. 215 5

We have established a new cell line from a patient with centrocytic B cell lymphoma. Highly purified peripheral blood B cells from patient DUL (WBC counts 158,000/microliters) were infected in vitro with Epstein-Barr virus (EBV), and CD20+ B cells were cloned into 96 well culture plates with the aid of a cell sorter autoclone device. As shown by GTG-banding and Southern blot analysis, out-growing EBV-positive clones had the same chromosomal abnormalities and identical monoclonal IgH gene rearrangement as the original EBV-genome-negative leukemic B cell clone. Surface marker analysis with a panel of monoclonal antibodies revealed identical patterns on EBV-negative and -positive clones, with the exception of PCA1 (reactive with plasma cells) which was negative on freshly explanted leukemic B cells but positive on EBV-converted clones.
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PMID:Establishment and characterization of a new Epstein-Barr virus transformed cell line from a human B cell lymphoma. 215 85

Epstein-Barr virus (EBV), a human herpesvirus, is strongly linked with two relatively rare forms of B-cell lymphoma and with a much more prevalent epithelial malignancy, undifferentiated nasopharyngeal carcinoma (NPC). The availability of suitable culture systems has allowed detailed analysis of EBV-induced growth transformation in B lymphocytes, but little is known about the virus--epithelial cell interaction or about the possible effector role of viral proteins in the pathogenesis of NPC. Here we describe an experimental system to monitor the effects of introduced viral or cellular genes upon human epithelial cell growth and differentiation. We transfected a human epithelial cell line, which retains several features of normal keratinocyte behaviour in vitro, with the EBV gene encoding latent membrane protein (LMP), one of only two viral proteins known to be expressed in NPC cells in vivo. LMP expression was accompanied by changes in the epithelial cell surface phenotype, mimicking surface changes observed in NPC cells, and by severe impairment of the cellular response to differentiation signals. The ability of LMP to inhibit terminal differentiation indicates a mechanism whereby EBV infection of squamous epithelium could contribute to the multi-step pathogenesis of NPC.
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PMID:Epstein-Barr virus latent membrane protein inhibits human epithelial cell differentiation. 215 28

Burkitt's lymphoma is the most common childhood cancer in Africa. Most prevalent in areas endemic for malaria, the disease, a malignant growth of lymphoid tissue, usually presents itself as a large tumour of the jaw. When first characterized in the 1950s, the lymphoma was thought to spread by some infectious agent. Subsequent research indicates that the frequent involvement of an infectious agent is but one factor in a more complex aetiology. Today, Burkitt's lymphoma is considered an example of multistep carcinogenesis. Each step in the process results from a different agent. The agent in the first step is the Epstein-Barr virus, which infects B cells of the immune system causing a proliferation of these cells. The second step, malarial infection, furthers the proliferation of B cells providing a large population of cells available for a chromosomal translocation which represents the third step in the formation of the lymphoma. The chromosomal translocation places a cancer causing gene, c-myc, in close proximity to an active antibody-encoding its proliferation resulting in a cell capable of unlimited growth which serves as the nucleus of a B cell lymphoma.
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PMID:Burkitt's lymphoma and the role of Epstein-Barr virus. 216 60

Type-C virus-like particles (VLPs) were found in an Epstein-Barr (EB) virus-infected human B-cell lymphoma cell line, SP-50B, that was established from a patient with non-Hodgkin lymphoma. The cell line continuously produces a small number of type-C VLPs, 150-200 nm in diameter, over 1 year. SP-50B cells were negative for HTLV-I and HTLV-II antigens and did not contain the HTLV-I genome. In addition, two EB virus nuclear antigen (EBNA)-positive B-cell lines, SP-54-Cord and SP-57-CLL, were established from human cord blood and chronic lymphocytic leukemia (CLL), respectively, by coculture with lethally irradiated SP-50B cells. Type-C VLPs with the same morphology were also found in both cell lines.
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PMID:Type-C virus-like particles in a human B-cell lymphoma cell line. 216 9

A case of primary leptomeningeal B-cell lymphoma in an 8-year-old, previously healthy child is described. The child was found to have hypogammaglobulinemia, and the Epstein-Barr virus genome was identified in cultured tumor cells despite blood serology being negative for the virus. The patient was treated with cyclophosphamide, doxorubicin, vincristine, and dexamethasone, plus intrathecal methotrexate, and initially improved. Before the initiation of craniospinal radiation, the patient developed progressive disease, deteriorated, and died 9 months after the onset of symptoms.
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PMID:Primary leptomeningeal B-cell lymphoma in a 8-year-old child. 217


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