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

B cell dysfunction associated with HIV infection includes polyclonal B cell activation and hypergammaglobulinemia. There is also an elevated frequency of B cell malignancies, especially non-Hodgkin's lymphoma, in HIV infection. It is believed that chronic polyclonal activation of B cells might increase the chances for the occurrence of a genetic accident, resulting in tumorigenesis. Long-term zidovudine use in people with HIV infection has been reported to be associated with a particularly high incidence of B cell lymphoma. This may be due to an increase in life span associated with antiretroviral treatment, placing treated individuals at risk for developing lymphoma for a greater period of time. However, zidovudine could be directly contributing to lymphoma-genesis in HIV-infected individuals, perhaps by enhancing B cell activation, since B cell hyperactivation and elevated levels of IL-6, a B cell stimulatory cytokine, are seen in HIV infection. Also, people treated with zidovudine may inherently be at higher risk for developing lymphoma because of the relatively greater degree of immune impairment seen in those that receive treatment with this drug. To examine if exposure to zidovudine resulted in enhanced B cell activation, we determined whether or not the presence of zidovudine enhanced B cell activation or IL-6 production in vitro or in vivo. Exposure to zidovudine in vitro did not enhance spontaneous immunoglobulin or IL-6 secretion by cells from HIV-infected (or uninfected) subjects and did not enhance B cell activation induced by EBV or affect the ability of T cells to regulate EBV-activated B cells. Neither serum immunoglobulin or IL-6 levels, nor the expression of cell surface activation markers on circulating B cells, were seen to increase following zidovudine treatment. These results indicate that zidovudine does not induce B cell activation in vivo or in vitro, suggesting that zidovudine treatment does not contribute to lymphomagenesis by enhancing B cell hyperstimulation.
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PMID:Effects of zidovudine on B lymphocyte activation. 808 61

Interleukin-5 (IL-5) and IL-6 have both been reported to act as B-cell differentiation factors by stimulating activated B cells to secrete antibody. However, it has not been possible to directly compare the effects of these two lymphokines because of the lack of a suitable B-cell line capable of responding to both. We have identified a clonal, inducible B-cell lymphoma, CH12, that has this property. Both IL-5 and IL-6 can independently stimulate increases in steady-state levels of immunoglobulin and J-chain mRNA and proteins, and they both induce the differentiation of CH12 into high-rate antibody-secreting cells. Nevertheless, there are significant differences in the activities of these two lymphokines. First, while IL-6 acts only as a differentiation factor, IL-5 also augments the proliferation of CH12 cells. Second, the differentiation stimulated by IL-5 but not by IL-6 is partially inhibited by IL-4. Inhibition of IL-5-induced differentiation was not at the level of IL-5 receptor expression, since IL-4 did not inhibit IL-5-induced proliferation. Third, IL-5 but not IL-6 stimulated increased mouse mammary tumor proviral gene expression in CH12 cells. These results demonstrate that while both IL-5 and IL-6 may act as differentiation factors for B cells, they induce differentiation by using at least partially distinct molecular pathways. Our results also establish that B cells characteristic of a single stage of development can independently respond to IL-4, IL-5, and IL-6.
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PMID:Interleukin-5 (IL-5) and IL-6 define two molecularly distinct pathways of B-cell differentiation. 832 Dec

Cytokines play important roles in the pathogenesis of lymphomas. Cytokines either can be produced or exert effects on neoplastic or reactive cells. The secretion of cytokines can provide growth advantages for tumor cells in either an autocrine or a paracrine fashion. An elevated serum or tissue level of cytokines can contribute to the clinical and histopathologic alterations associated with malignant lymphomas. The effects of cytokines on the histopathologic changes are most noticeable in Hodgkin's disease (HD). The malignant (Hodgkin's-Reed-Sternberg) cells in HD have been shown to secrete interleukin-1 (IL-1), IL-5, IL-6, IL-9, tumor necrosis factor-alpha, macrophage colony-stimulating factor, transforming growth factor-beta, and, less frequently, IL-4 and granulocyte colony-stimulating factor. These cytokines may be responsible for the increased cellular reaction and fibrosis observed in tissues involved by HD and for the immunosuppression in patients with HD. In contrast to Hodgkin's-Reed-Sternberg cells, most non-HD lymphoma cells do not produce cytokines in excess amounts. Exceptions include T-cell-rich B-cell lymphoma (IL-4), angioimmunoblastic lymphadenopathy-like T-cell lymphoma with plasmacytosis and hypergammaglobulinemia (IL-6), anaplastic large-cell lymphoma (IL-9), polymorphic immunocytoma (IL-6), and immunoblastic lymphoma (IBL) (IL-6). Some cytokines are involved in the unique cellular reactions in each of these types of lymphoma. For example, IL-4 is responsible for the T-cell reaction in T-cell-rich B-cell lymphoma, while IL-6 is accountable for the plasma cell reaction in angioimmunoblastic lymphadenopathy-type T-cell lymphoma. Others may be directly involved in the tumor cell growth or differentiation. For instance, IL-9 may be important for the autocrine proliferation of anaplastic large cell lymphoma, whereas IL-6 is essential for plasmacytoid differentiation in polymorphic immunocytoma. Further studies of the roles of cytokines in lymphomas may lead to major advances in the understanding of the molecular processes involved in the histopathogenesis of malignant lymphomas. Elucidation of the autocrine or paracrine function of cytokines also may lead to new approaches to a rational intervention in these disease processes.
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PMID:Cytokines in malignant lymphomas: review and prospective evaluation. 840 14

Interleukin (IL)-1 alpha, IL-1 beta, tumor necrosis factor (TNF) alpha, and IL-6 are the most important triggers in the response of the immune system to infection and neoplasia. We examined the histochemical distribution of cytokine-possessing cells in neoplastic lymph nodes of 68 malignant lymphomas. The HLA-DR positive interdigitating reticulum cells (IRCs), histiocytes/macrophages (H/Ms) and epithelioid histiocytes with these cytokines were frequently encountered in Hodgkin's disease, B cell lymphoma of lymphoplasmacytic/cytoid, centroblastic and immunoblastic types, and T cell lymphoma of Lennert's and anaplastic large cell types. In almost all cases of B cell lymphoma of chronic lymphocytic leukemia, centrocytic, follicular centroblastic/centrocytic, Burkitt's types and T cell lymphoma of lymphoblastic, angioimmunoblastic lymphadenopathy and pleomorphic types, the cytokine-possessing cells were rarely or occasionally present. These lymphomas with less cytokines had also few or occasionally encountered IRCs, while H/Ms were frequently or occasionally present. Well-developed dendritic reticulum cells in some types of lymphoma had few cytokines. The population of cytokine-possessing cells was related with histologic type of lymphoma and the volume of IRCs. The IRCs might act as an important initiator of reactive cells against tumor cells. In addition, neoplastic T cells influenced the cytokines' possession of IRCs and H/Ms. Although lacunar, Hodgkin's and Reed-Sternberg cells in Hodgkin's disease and the neoplastic cells in peripheral T cell lymphoma showed weak positive reaction of TNF alpha in one third of the cases, lymphoma cells in the majority might have few cytokines, especially IL-1s and IL-6.
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PMID:Cytokine (interleukin-1 alpha, interleukin-1 beta, tumor necrosis factor alpha, and interleukin-6)-possessing cells in lymph nodes of malignant lymphoma. 851 12

The human interleukin-3 receptor (IL-3R) is expressed on myeloid, lymphoid, and vascular endothelial cells, where it transduces IL-3-dependent signals leading to cell activation. Although IL-3R activation may play a role in hematopoiesis and immunity, its aberrant expression or excessive stimulation may contribute to pathologic conditions such as leukemia, lymphoma, and allergic reactions. We describe here the generation and characterization of a monoclonal antibody (MoAb), 7G3, which specifically binds to the IL-3R alpha-chain and completely abolishes its function. MoAb 7G3 immunoprecipitated and recognized in Western blots the IL-3R alpha-chain expressed by transfected cells and bound to primary cells expressing IL-3R alpha. MoAb 7G3 bound the IL-3R alpha-chain with a kd of 900 pmol/L and inhibited 125I-IL-3 binding to high- and low-affinity receptors in a dose-dependent manner. Conversely, IL-3 but not granulocyte-macrophage colony-stimulating factor (GM-CSF) inhibited 125I-7G3 binding to high- and low-affinity IL-3Rs, indicating that MoAb 7G3 and IL-3 bind to common or adjacent sites. In keeping with the inhibition of IL-3 binding, MoAb 7G3 antagonized IL-3 biologic activities, namely stimulation of TF-1 cell proliferation, basophil histamine release, and IL-6 and IL-8 secretion from human endothelial cells. Two other anti-IL-3R alpha-chain MoAbs failed to inhibit IL-3 binding or function. Epitope mapping experiments using truncated IL-3R alpha-chain mutants and IL-3R alpha/GM-CSFR alpha chimeras revealed that 31 amino acids in the N-terminus of IL-3R alpha were required for MoAb 7G3 binding. MoAb 7G3 may be of clinical significance for antagonizing IL-3 in pathologic conditions such as some myeloid leukemias, follicular B-cell lymphoma, and allergy. Furthermore, these results implicate the N-terminal domain of IL-3R alpha in IL-3 binding. Since this domain is unique to the IL-3/GM-CSF/IL-5 receptor subfamily, it may represent a novel and common binding feature in these receptors.
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PMID:Monoclonal antibody 7G3 recognizes the N-terminal domain of the human interleukin-3 (IL-3) receptor alpha-chain and functions as a specific IL-3 receptor antagonist. 854 80

Physiologically, B-lymphocytes are not present in the skin. Even in pathological situations they rarely occur. In contrast, primary cutaneous B-cell lymphomas (CBCL) are characterized by proliferation of B lymphocytes within the skin. This suggests the existence of a certain microenvironment supporting homing and expansion of clonal B cells. Cytokines were demonstrated to be involved in the pathogenesis of cutaneous lymphomas of T-cell origin. Cytokine expression in cutaneous B-cell lymphoma lesions, however, has not been investigated so far. Therefore, the mRNA level of several cytokines was analyzed in biopsies from 7 patients with CBCL and compared to pleomorphic T-cell lymphoma (n = 6), psoriasis (n = 9), and healthy skin (n = 7), using a competitive RT-PCR approach. An overexpression of TNF-alpha, IL-10, and IL-6 was found. Enhanced IL-8 mRNA expression was detected in 2/7 cases. The overexpression of IL-6 and IL-10 in CBCL might be of particular importance, since these cytokines are considered to support B-cell growth. Additionally, the overexpression of IL-10 may contribute to tumor progression since this immunosuppressive cytokine might be involved in downregulation of immunological tumor surveillance, in part by inhibiting type 1 cytokine formation. In fact, we did not detect IFN-gamma and IL-2 expression. Taken together, we found a cytokine pattern in CBCL lesions which might contribute to tumor B-cell growth.
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PMID:Cytokine expression in primary cutaneous germinal center cell lymphomas. 1068 78

Epstein-Barr virus (EBV)-induced lymphoproliferative disease (lpd) is a B cell neoplasm that affects patients who are immunosuppressed in the context of organ transplantation or HIV infection. A model for the aggressive form of this entity was generated by xenotransplantation of SCID mice with human peripheral blood leukocytes from individuals with prior contact with EBV. This model, where large B cell lymphoma occurs, was used to test the hypothesis that IL-6 has a major role in EBV-induced B cell tumorigenesis. IL-6 is known to differentiate B cells into immunoglobulin-secreting plasma cells and induce EBV replication, and xenochimeric animals have detectable serum levels of human IL-6. Human IL-6 inhibition with a neutralizing monoclonal antibody decreased tumor incidence from 62 % to 27 %. In addition, anti-IL-6 treatment significantly improved xenotransplanted animal survival, with median survival at > 245 days when compared to that of controls at 132 days. In conclusion, IL-6 plays a critical role in the pathogenesis of EBV-induced human lpd, and IL-6 inhibition may represent a new and promising preventive or therapeutic approach against this malignancy.
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PMID:Epstein-Barr virus-dependent lymphoproliferative disease: critical role of IL-6. 1094 Aug 96

Seven patients with peripheral B-cell lymphoma associated with hemophagocytic syndrome are reported. In all cases, the histologic subtype was diffuse large B-cell lymphoma. Hemophagocytic features were noted in the bone marrow with lymphomatous infiltration. Hemophagocytic syndrome occurred with presentation of the lymphoma and was characterized by high fever, cytopenias, and elevated levels of lactate dehydrogenase, ferritin, C-reactive protein, and cytokines [interferon gamma, macrophage colony-stimulating factor, soluble interleukin (sIL)-2R, and IL-6] without evidence of infection. The phenotypes of lymphomas were suspected CD19+, CD20+, S-Ig+, CD10-, and coexpression of CD5 in some cases. Flow cytometric analysis showed a low CD4/CD8 ratio in peripheral blood and bone marrow. We suggest that the pathogenesis of hemophagocytic syndrome is hypercytokinemia induced by a proliferation of reactive CD8+ T cells. Previous reports of B-cell lymphoma with hemophagocytic syndrome demonstrated similar clinical manifestations and poor prognoses. The invasion patterns of these diffuse large B-cell lymphomas with hemophagocytosis may be classified into three groups: microscopic lymph-node involvement type, gross lymph-node involvement type, and splenic lymphoma type. Although hemophagocytic syndromes have been reported to be associated with T-cell lymphomas, our results indicate an association with diffuse large B-cell lymphoma.
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PMID:B-cell lymphoma-associated hemophagocytic syndrome: clinicopathological characteristics. 1096 86

A case of angiotropic B-cell lymphoma associated with hemophagocytic syndrome (HPS) has been reported. In addition to fever, pancytopenia, hepatosplenomegaly, and lack of lymphadenopathy, unique clinical features, such as syndrome of inappropriate secretion of antidiuretic hormone (SIADH) and pulmonary infarction, were manifested. Both soluble interleukin-2 receptor (sIL-2R) and IL-6 were elevated in the patient's sera in addition to an increase of serum lactate dehydrogenase and ferritin. In contrast, tumor necrosis factor-alpha and interferon-gamma were within normal ranges. Serum antibodies against Epstein-Barr virus and cytomegalovirus showed a past infection pattern. An autopsy examination revealed systemic intravascular proliferation of lymphoma cells with a B-cell phenotype, confirming the diagnosis of angiotropic B-cell lymphoma. Moreover, SIADH was suggested to result from the infiltration of tumor cells into the pituitary gland. Triple association of angiotropic B-cell lymphoma, HPS and SIADH is quite rare. Therefore, the present case seems to be helpful for clarifying the mechanism for HPS of non-Hodgkin's lymphoma with B-cell origin.
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PMID:Angiotropic B-cell lymphoma with hemophagocytic syndrome associated with syndrome of inappropriate secretion of antidiuretic hormone. 1110 Jul 51

Malignant lymphoma is a major cause of hemophagocytic syndrome (HPS), in which reactive macrophages, phagocytic red blood cells, white blood cells, and platelets proliferate in bone marrow, liver, and spleen. In contrast to T/NK-cell lymphoma-associated hemophagocytic syndrome (T/NK-LAHS), few cases of B-LAHS have been reported; thus, the clinical characterization of B-LAHS remains to be established. We describe here four cases of B-LAHS that include the following features: (1) HPS was the initial presentation; (2) bone marrow involvement with large-cell lymphomas was noted in all cases, despite lack of remarkable lymphadenopathy; (3) no active infection with Epstein-Barr virus as the etiological agent was confirmed; (4) except for the spleen in one case, primary site of lymphoma could not be determined; and (5) serum IL-6, soluble IL-2 receptor, and IFN-gamma- but not TNF-alpha and IL-1 beta-, were significantly elevated. Such characteristics are peculiar to and different from those usually seen in B-cell lymphoma, suggesting that B-LAHS is a unique clinical entity among B-cell lymphomas.
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PMID:[Clinical characterization of B cell lymphoma-associated hemophagocytic syndrome]. 1115 15


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