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)

For many non-Hodgkin's lymphomas, the bcl-2 gene has been implicated as a likely proto-oncogene, since it is consistently located at or near the breakpoint sites of t(14;18) chromosomal translocations. To define the role of the protein product of the bcl-2 gene in lymphoid cancers, we used anti-bcl-2 antibodies to perform immunohistochemical studies of frozen sections of 136 tissue specimens affected by lymphoma or non-neoplastic lymphoid disorders. Immunoreactive bcl-2 protein was observed in the neoplastic cells in almost all the follicular lymphomas, whereas no bcl-2 protein was detected in follicles affected by non-neoplastic processes or in normal lymphoid tissue. Every tumor with molecular-genetic evidence of t(14;18) translocation expressed detectable levels of bcl-2 protein, regardless of whether the breakpoint was located in or at a distance from the bcl-2 gene. These data show consistent expression of a proto-oncogenic protein in a large proportion of non-Hodgkin's lymphomas and provide further support of a role for bcl-2 in the pathogenesis of all lymphomas with the t(14;18) karyotypic abnormality. Increased expression of bcl-2 after t(14;18) translocations may be a specific marker for B-cell cancers, and demonstration of the protein with use of anti-bcl-2 antibodies could be useful in the diagnosis of many non-Hodgkin's lymphomas.
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PMID:Expression in non-Hodgkin's lymphoma of the bcl-2 protein associated with the t(14;18) chromosomal translocation. 328 62

One of the most common karyotypic abnormalities is the t(14;18) translocation, which is found in many lymphomas that have a characteristic follicular morphology. Recent molecular studies have shown that this chromosomal translocation results in the juxtaposition of the candidate proto-oncogene bcl-2 (B-cell leukemia-lymphoma) on chromosome 18 with the immunoglobulin heavy-chain locus on chromosome 14. However, because performing accurate cytogenetic studies in solid hematolymphoid neoplasms is difficult, knowledge of the prevalence of the t(14;18) translocation and, by association, the extent of bcl-2 involvement in human lymphomas is limited. We used a number of chromosome-18 DNA probes to analyze various subtypes of Hodgkin's and non-Hodgkin's lymphomas and test for structural abnormalities near or within the bcl-2 gene. Molecular features of the t(14;18) translocation were found in virtually all follicular neoplasms and about 28 percent of diffuse large-cell lymphomas. No changes in bcl-2 were found in several other subtypes of Hodgkin's and non-Hodgkin's lymphomas, including those previously suggested to originate from follicular-center cells and those about which cytogenetic data have been difficult to obtain. Our findings suggest a close pathogenetic relation between bcl-2 and a large group of non-Hodgkin's lymphomas, both with and without a follicular morphology. The methods employed in this study may be useful in improving the accuracy of diagnosis and subclassification of malignant lymphomas.
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PMID:Molecular analysis of the t(14;18) chromosomal translocation in malignant lymphomas. 365 90

The expression of the proto-oncogene bcl-2 was examined in a panel of 75 continuous human leukemia-lymphoma cell lines originated from different hematopoietic cell types. The presence of the bcl-2 protein, as evidenced by Western blotting, and its mRNA, as determined by Northern blotting, were not restricted to cells with the chromosomal translocation t(14;18)(q32;q21), but were also detected in a large number of cell lines without t(14;18). The amount of the bcl-2 protein and mRNA in the cell lines with t(14;18) was in the same order of magnitude as in other bcl-2 expressing cell lines of the same lineage, but without the translocation. Bcl-2 was found in all types of hematopoietic cell lines which were assigned to the following lineages based on their phenotypical characteristics: pre-B, B, plasma, T, myeloid, monocytic, erythroid-megakaryocytic and Hodgkin's lymphoma derived cell lines. The levels of accumulated mRNA and protein corresponded fairly well in most of the cell lines examined. Our results suggest the notion that bcl-2 expression is widely present in hematopoietic cell lines without restriction to single lineages and, in fact, clearly independent of the chromosomal aberration t(14;18). It is conceivable that bcl-2 expression is a common feature in established hematopoietic cell lines and may contribute to their unlimited growth in vitro.
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PMID:Expression of bcl-2 mRNA and protein in leukemia-lymphoma cell lines. 747 72

We studied a variant CD5- B cell chronic lymphocytic leukemia (CLL) cell population that produces pathologic IgM kappa rheumatoid factor autoantibodies. In contrast to common CD5+ B cell CLL, this variant leukemia cell population displays intraclonal diversity in its expressed Ig V genes, similar to that noted for follicular B cell non-Hodgkin's lymphomas. Also, in contrast to common B cell CLL, these leukemia cells rapidly undergo cell death hours after being placed in tissue culture. We find that addition of Ag (aggregated human IgG) enhances significantly the survival of these cells in vitro. Leukemia cell survival also could be enhanced by exogenous IFN-gamma or anti-CD40 presented on Fc gamma RII (CDw32)-expressing L cells, but not by exogenous IL-4, IL-6, or monomeric human IgG. We find that Ag acts directly on the leukemia B cells to inhibit apoptosis. This effect could be mimicked by cross-linking the leukemia cells' surface IgM receptors with immobilized murine mAb specific for human Ig mu-chains, but not by immobilized mAb of irrelevant specificity. In contrast to most follicular NHL, this leukemia B cell population does not have evidence of bcl-2 gene rearrangement. Also, in contrast to non-Hodgkin's lymphomas and most B cell CLL, these cells do not express detectable amounts of bcl-2. Finally, although capable of inhibiting apoptosis, surface Ig receptor cross-linking does not induce expression of bcl-2 in these variant leukemia cells. We hypothesize that the lack of bcl-2 expression may render these leukemia cells particularly dependent upon the survival signal(s) derived from surface Ig receptor cross-linking. This state may represent an early stage in leukemia/lymphomagenesis, possibly accounting for the intraclonal diversity observed in the Ig V genes expressed by certain CD5- B cell leukemias and lymphomas.
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PMID:Autoantigen inhibits apoptosis of a human B cell leukemia that produces pathogenic rheumatoid factor. 750 24

CD40 is a transmembrane protein that belongs to a superfamily of proteins related to nerve growth factor receptor. CD40 is expressed on B cells and some B cell malignancies. It appears to be involved in B cell proliferation and the prevention of apoptosis in germinal center cells, which is accompanied by expression of bcl-2. Its expression is up-regulated by the EBV protein latent membrane protein-1 and cytokines interleukin-4 and interferon-gamma. The expression of CD40 in 37 cases of Hodgkin's disease and 23 cases of non-Hodgkin's lymphoma (11 T cell lymphomas and 12 B cell lymphomas) was examined by paraffin section immunohistochemistry using the BB-20 monoclonal antibody. In 26 of 37 cases of Hodgkin's disease the Reed-Sternberg cells showed strong membrane or cytoplasmic expression of CD40. Only 3 of 23 non-Hodgkin's lymphomas showed any expression of CD40 and then only weakly. There was no correlation between expression of bcl-2 or latent membrane protein-1 with CD40 expression. These results show that there is probable hyperexpression of CD40 in Hodgkin's disease and suggest that dysregulation of CD40 expression may play a role in the pathogenesis of Hodgkin's disease.
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PMID:CD40 expression in Hodgkin's disease. 753 45

One hundred three cases of nodular sclerosis (NS) and mixed-cellularity Hodgkin's disease were evaluated for expression of bcl-2 oncogene protein, because previous studies have revealed expression of bcl-2 in these subtypes but only rarely in the nodular lymphocyte-predominance subtype. Reed-Sternberg (RS) cells and lacunar variants were positive for bcl-2 in 51 of 86 NS cases and 4 of 17 mixed-cellularity cases. In individual cases of NS, the percentage of RS cells and lacunar variants positive for bcl-2 ranged from minimal (in 5 cases) to 100% positive (mean, 34%). By univariate analysis, expression of the bcl-2 gene product in RS cells was observed in a significantly greater proportion of NS Hodgkin's disease cases than MC cases (P < .009), a finding that may have implications on the pathogenesis of this disorder.
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PMID:Bcl-2 oncogene protein is preferentially expressed in Reed-Sternberg cells in Hodgkin's disease of the nodular sclerosis subtype. 752 1

Recent nucleic acid hybridization studies have implied that Reed-Sternberg/Hodgkin (RS/H) cells are infected with Epstein-Barr virus (EBV) before malignant transformation, and hence, that Hodgkin's disease could develop as a consequence of malignant transformation of an EBV-infected cell. This study is a detailed immunohistochemical and in situ hybridization characterization of the various lymphoid cells in nine cases of infectious mononucleosis (IM), the acute manifestation of EBV infection. The RS/H-like cells of IM were similar in most respects to their morphologically identical counterparts in Hodgkin's disease; they expressed the EBV-encoded protein LMP1, EBV EBER1 transcripts, and CD30 and rarely, if ever, expressed CD45/LCA or T cell markers. Dissimilarities were limited to CD15 negativity and the absence of a collarette of T cells around the RS/H-like cells of IM compared with their Hodgkin's counterparts. Expression of the immortalizing bcl-2 oncoprotein was variable in the RS/H-like cells of IM, as has been demonstrated in the RS/H cells of Hodgkin's disease by other investigators. An apoptosis assay suggested that many apoptotic cells in IM were EBV-infected T cells, in keeping with the previous in vitro observation that IM-derived T cells succumb to apoptosis. Additionally, the apoptosis assay suggested that RS/H-like cells of IM can succumb to programmed cell death, reminiscent of the mummified RS/H cells seen in Hodgkin's disease. The accumulation of evidence suggests that RS/H-like cells of IM are more similar to true RS/H cells than previously recognized.
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PMID:New characterization of infectious mononucleosis and a phenotypic comparison with Hodgkin's disease. 753 53

Conflicting data on the presence of bcl-2/JH gene rearrangement and BCL-2 protein expression in Hodgkin's disease (HD) have been reported. To find out the reason for these differences, well characterized cases from the German National Trial were examined by PCR for the bcl-2 gene rearrangement and immunohistochemically for BCL-2 protein expression. No bcl-2/JH rearrangement could be detected among the HD analyzed from paraffin sections, as well as another 24 cases of HD investigated in fresh tissue. Contrasted with this, immunohistochemistry demonstrated BCL-2 protein expression in all types of HD. In conclusion, our results suggest that the bcl-2/JH gene rearrangement does not play a role in HD, but BCL-2 protein is frequently expressed by RS/H cells of non-lymphocyte predominance subtypes.
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PMID:[Hodgkin lymphomas ar negative with regard to bcl-2/JH gene rearrangement, but partly express BCL-2 protein: analysis of 83 cases from the German Hodgkin Trial]. 753 7

Diffuse large B cell lymphomas (DLBLs) represent a heterogeneous collection of aggressive non-Hodgkin's lymphomas that can arise either de novo or as a result of transformation from chronic lymphocytic leukemia, small lymphocytic lymphoma, follicular lymphomas, or lymphomas of mucosa-associated lymphoid tissue. A small percentage of DLBLs express the CD5 antigen. The majority of these cases have evolved from a pre-existing low grade non-Hodgkin's lymphoma (Richter's syndrome). However, we identified and characterized nine CD5-positive DLBLs in which the patients did not have a previous history or concomitant evidence of chronic lymphocytic leukemia, small lymphocytic lymphoma, follicular lymphoma, or mucosa-associated lymphoid tissue-associated non-Hodgkin's lymphoma, suggesting that they arose de novo. All nine cases expressed CD20 and monotypic immunoglobulin, all eight cases examined expressed CD19, CD22 and CD43, eight of the nine cases expressed HLA-DR, and two of eight cases expressed CD11c. None of the cases expressed CD3, CD10, CD11b, CD21, CD23 or CD30. CD5 expression by these cells was found to be identical to that of CD5-positive B cell chronic lymphocytic leukemia by quantitative polymerase chain reaction analysis of CD5 mRNA. These nine de novo CD5-positive DLBLs exhibited clonal immunoglobulin heavy and light chain gene rearrangements but lacked integration of the Epstein-Barr virus genome and structural alterations of the bcl-1, bcl-2, c-myc, H-ras, K-ras, and N-ras proto-oncogenes and the p53 tumor suppressor gene. However, bcl-6 proto-oncogene rearrangement, which is involved in chromosome band 3q27 aberrations, was found in four cases (44.4%). This is comparable with the frequency of bcl-6 gene rearrangement in CD5-negative DLBL. In contrast, bcl-6 gene rearrangement was absent in six cases of DLBL associated with Richter's syndrome. These findings suggest that de novo CD5-positive DLBLs are genotypically similar to CD5-negative DLBLs and may be pathogenetically distinct from the DLBLs associated with Richter's syndrome.
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PMID:De novo CD5-positive and Richter's syndrome-associated diffuse large B cell lymphomas are genotypically distinct. 754 11

Among extranodal non-Hodgkin's lymphomas, primary cutaneous lymphomas (CLs) represent a consistent group of B- and T-cell malignancies. We investigated the arrangement of Ig and T-cell receptor (TCR) genes, together with the involvement of several oncogenes and the tumor-suppressor gene p53, in a panel of primary cutaneous B- and T-cell lymphomas (CBCLs and CTCLs). Southern blot analysis was performed to detect rearrangements of the Ig, c-myc, bcl-1, bcl-2, bcl-3, bcl-6, and the NFKB2/lyt-10 genes in 52 cases of CBCLs and of the TCR, bcl-3, and NFKB2/lyt-10 genes in 38 cases of CTCLs. tal-1 gene deletions were analyzed in CTCLs by means of polymerase chain reaction (PCR). p53 gene mutations were assayed using PCR, single-strand conformation polymorphism analysis, and direct DNA sequencing in CBCL and CTCL cases. Clonal rearrangements of Ig genes or oncogenes were found in 25 of the 52 CBCLs. In particular, we detected rearrangements of the bcl-1 locus (2 cases), the bcl-2 gene (2 cases), the NFKB2/lyt-10 gene (2 cases), and the bcl-6 gene (1 case); interestingly, 4 of these cases showed a germline arrangement of the Ig genes. Clonal rearrangements of TCR genes were detected in 37 of the 38 CTCLs. Rearrangements of the NFKB2/lyt-10 gene were present in 2 cases and tal-1 gene deletions in 3 CTCL cases; p53 gene mutations were detected in 1 CTCL case. Overall, our data indicate that (1) clonal rearrangement of Ig genes is frequently undetectable by means of Southern blot in CBCLs (60%); (2) genetic lesions are involved in a limited but significant fraction of primary CLs showing a molecular marker of clonality (13/62; 20%); and (3) rearrangements of the bcl-1, bcl-2, or bcl-6 loci, associated with specific subsets of nodal lymphoid neoplasias, are rarely observed in CBCLs. Moreover, our results suggest that tal-1 gene deletions may play a pathogenetic role in non-acute T-cell malignancies and that, in the context of lymphoid malignancies, CLs may represent a favorable target for the possible oncogenic potential of the NFKB2/lyt-10 gene.
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PMID:Molecular analysis of cutaneous B- and T-cell lymphomas. 757 11


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