Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0019829 (Hodgkin's disease)
 30,247 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

To elucidate the role of cell turnover in primary gastric B-cell non-Hodgkin's lymphomas we studied tissue samples of 72 patients-26 small cell (25 MALT lymphomas) and 46 large cell (31 MALT lymphomas). Proliferation indices and apoptotic indices were measured by Mib-1 expression and terminal deoxynucleotidyltransferase (TdT)-mediated nick end labelling, respectively. Furthermore, expression of the apoptosis related gene-products bcl-2 and p53 was studied. Large cell lymphomas showed significantly higher proliferation indices (59.1% vs. 15.4%) and apoptotic indices (3.2% vs.0.7%) than small cell lymphomas. Proliferation and apoptotic indices were positively correlated (r = 0.371, P = 0.03). Expression of the bcl-2 protein was significantly higher in the small cell lymphomas. Furthermore, cases with a high bcl-2 expression showed both a significantly decreased proliferation (P < 0.0001) and apoptotic index (P = 0.0096) compared to bcl-2 negative cases. Expression of the mutant p53 protein was present in 8.0% of small cell and in 18.2% of large cell lymphomas. p53 positive cases showed significantly higher proliferation indices, but showed no correlation with apoptotic index. These data suggest that impaired apoptosis by bcl-2 may be more prominent than proliferation in the genesis of small cell lymphomas, whereas a high cell turnover characterizes large cell primary gastric lymphomas.
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PMID:Proliferation and apoptosis in primary gastric B-cell non-Hodgkin's lymphoma. 906 40

The human BMI-1 and EZH2 polycomb group (PcG) proteins are constituents of two distinct complexes of PcG proteins with gene regulatory activity. PcG proteins ensure correct embryonic development by suppressing homeobox genes, and they also contribute to regulation of lymphopoiesis. The two PcG complexes are thought to regulate different target genes and probably have different tissue distributions. Altered expression of PcG genes is linked to transformation in cell lines and induction of tumors in mutant mice, but the role of PcG genes in human cancers is relatively unexplored. Using antisera specific for human PcG proteins, we used immunohistochemistry and immunofluorescence to detect BMI-1 and EZH2 PcG proteins in Reed-Sternberg cells of Hodgkin's disease (HRS). The expression patterns were compared to those in follicular lymphocytes of the lymph node, the normal counterparts of HRS cells. In the germinal center, expression of BMI-1 is restricted to resting Mib-1/Ki-67(-) centrocytes, whereas EZH2 expression is associated with dividing Mib-1/Ki-67(+) centroblasts. By contrast, HRS cells coexpress BMI-1, EZH2, and Mib-1/Ki-67. Because HRS cells are thought to originate from germinal center lymphocytes, these observations suggests that Hodgkin's disease is associated with coexpression of BMI-1 and EZH2 in HRS cells.
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PMID:Coexpression of BMI-1 and EZH2 polycomb group genes in Reed-Sternberg cells of Hodgkin's disease. 1098 Jan 9

Polycomb-group (PcG) proteins, such as BMI-1 and EZH2, form multimeric gene-repressing complexes involved in axial patterning, hematopoiesis, and cell cycle regulation. In addition, BMI-1 is involved in experimental lymphomagenesis. Little is known about its role in human lymphomagenesis. Here, BMI-1 and EZH2 expression patterns are analyzed in a variety of B-cell non-Hodgkin lymphomas (B-NHLs), including small lymphocytic lymphoma, follicular lymphoma, large B-cell lymphoma, mantle-cell lymphoma, and Burkitt lymphoma. In contrast to the mutually exclusive pattern of BMI-1 and EZH2 in reactive follicles, the neoplastic cells in B-NHLs of intermediate- and high-grade malignancy showed strong coexpression of BMI-1 and EZH2. This pattern overlapped with the expression of Mib-1/Ki-67, a marker for proliferation. Neoplastic cells in B-NHL of low-grade malignancy were either BMI-1(low)/EZH2(+) (neoplastic centroblasts) or BMI-1(low)EZH2(-) (neoplastic centrocytes). These observations show that low-, intermediate-, and high grade B-NHLs are associated with increased coexpression of the BMI-1 and EZH2 PcG proteins, whose normal expression pattern is mutually exclusive. This expression pattern is probably caused by a failure to down-regulate BMI-1 in dividing neoplastic cells, because BMI-1 expression is absent from normal dividing B cells. These observations are in agreement with findings in studies of Bmi-1 transgenic mice. The extent of BMI-1/EZH2 coexpression correlated with clinical grade and the presence of Mib-1/Ki-67 expression, suggesting that the irregular expression of BMI-1 and EZH2 is an early event in the formation of B-NHL. This points to a role for abnormal PcG expression in human lymphomagenesis. (Blood. 2001;97:3896-3901)
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PMID:Coexpression of BMI-1 and EZH2 polycomb-group proteins is associated with cycling cells and degree of malignancy in B-cell non-Hodgkin lymphoma. 1138 32

Plasmablastic lymphoma (PBL) is a rare and relatively new entity originally described in HIV-infected individuals. This subset of Epstein-Barr-virus (EBV)-related non-Hodgkin lymphomas is now regarded as a distinct clinicopathological category of AIDS-associated lymphomas occurring preferentially in the oral cavity and showing a poor prognosis. We describe for the first time an EBV-associated PBL with an isolated cutaneous distribution on the lower extremities in an HIV-infected heterosexual male and point to the unique clinical, morphological and immunophenotypic characteristics of this lymphoma. The patient presented with fast growing solid and livid nodules on both legs. The large, blastic tumor cells showed the following immunophenotype: CD138+, CD45+, CD20-, CD10-, CD3-, CD30-, bcl-2-, bcl-6-, LMP-1- and EMA-. The proliferation fraction (Mib-1) was >90%. EBV association was demonstrated by in situ hybridization (EBV-encoded RNAs 1/2). Polymerase-chain-reaction-based DNA analysis demonstrated a clonal IgH rearrangement in the absence of a bcl-2/IgH translocation. PBL in HIV patients may occur not only in the oral cavity, but can probably involve any other organs including the skin.
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PMID:Cutaneous plasmablastic lymphoma in an HIV-positive male: an unrecognized cutaneous manifestation. 1511 93