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)

Sixty-four cases of mantle cell (centrocytic) non-Hodgkin's lymphomas have been analyzed for their cytomorphologic features, proliferation indices, bcl-1 rearrangements, p53 expression patterns, and DNA content by both interphase cytogenetic and DNA flow cytometric analyses. According to cytomorphology, three subtypes were recognized: a common, a lymphoblastoid, and a pleomorphic variant of mantle cell lymphoma (MCL). Blastoid MCL subtypes were characterized by distinctly elevated mitotic counts (57 and 51/10 HPF v 21/10 high-power fields in common MCL), proliferation indices (58% and 53% v 27% in common types, respectively; P < .001), frequent bcl-1 rearrangements at the major translocation cluster locus (59% v 40%), and overexpression of p53 (21% v 6%). However, the most interesting finding was a striking tendency of blastoid MCL subtypes to harbor chromosome numbers in the tetraploid range (36% of lymphoblastoid and 80% of pleomorphic types v 8% of common variants, P < .001), a feature clearly separating these neoplasms from other types of B-cell non-Hodgkin's lymphoma and possibly being related to cyclin D1 overexpression. Our data indicate that, although characterized by a uniform immunophenotype and common biologic background, MCL shows a broad spectrum of morphologic features ranging from small cell to blastoid types and that the morphologic spectrum is mirrored by distinct biologic features.
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PMID:Blastoid variants of mantle cell lymphoma: frequent bcl-1 rearrangements at the major translocation cluster region and tetraploid chromosome clones. 902 66

Recent studies have identified the integrin alpha 4 beta 7 as a mucosal homing receptor that mediates lymphocyte migration to the intestinal mucosa by binding to MAdCAM-1, a vascular recognition molecule (addressin) selectively expressed on mucosal endothelium. In the present study, we have assessed the expression of alpha 4 beta 7 on B- and T-cell non-Hodgkin's lymphomas of different primary localization and on related normal lymphocytes. Among B-lineage lymphomas, expression of alpha 4 beta 7 was present in the majority of cases of malignant lymphomatous polyposis of the intestine and low-grade lymphoma of the mucosa-associated lymphoid tissue/monocytoid B-cell lymphoma and in some cases of precursor B-cell lymphoma. CLL/small lymphocytic lymphoma, (nodal) mantle cell lymphoma, follicular center cell lymphoma, Burkitt's lymphoma, and diffuse large B-cell lymphoma were virtually always alpha 4 beta 7 negative, as was the case when localized in the mucosa-associated lymphoid tissue. The normal B cells of the follicle mantles and part of the B cells of the extrafollicular B-cell compartment of lymphoid tissues expressed moderate levels of alpha 4 beta 7. By contrast, follicular center cells were alpha 4 beta 7 negative. Among T-lineage lymphomas, expression of alpha 4 beta 7 was also strongly related to the primary localization; in mucosal, nodal, and cutaneous T cell lymphomas the percentage of positive cases was 56%, 17%, and 0%, respectively. All cases of precursor T-cell lymphoma were alpha 4 beta 7 negative. High expression of alpha 4 beta 7 was found on a subset of peripheral blood memory T cells as well as on lymphocytes in the intestinal mucosa. We conclude that non-Hodgkin's lymphomas that are related to mucosa-associated B- and T-lymphocyte populations selectively express the mucosal homing receptor alpha 4 beta 7. The presence of this receptor underscores their distinctive character and may play an important role in determining their characteristic mucosal dissemination pattern.
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PMID:Preferential expression of the mucosal homing receptor integrin alpha 4 beta 7 in gastrointestinal non-Hodgkin's lymphomas. 906 Aug 30

In 1992, after a history of more than two decades a subgroup within the diffuse low-grade B cell lymphomas designated centrocytic lymphoma, lymphocytic lymphoma of intermediate differentiation or mantle zone lymphoma gained general acceptance, now referred to as mantle cell lymphoma. Similarities between these entities were emphasized by identification of rearrangement and overexpression of CCND1 (bcl1/PRAD1) gene in the majority of cases. Unlike in all other non-Hodgkin's lymphomas sex distribution demonstrates a striking preponderance of males over females with a ratio of 3:1. Initial parameters in all published series are advanced disease with generalized lymphadenopathy in 90%, bone marrow infiltration in 60-75%, splenomegaly in 55%, hepatomegaly in 35%, gastrointestinal involvement in about 25% and peripheral blood lymphocytosis in 20-30% of patients. In generalized disease, clinical course is characterized by continuous progression with a median survival probability of 3-4 years within most series. Overall response rates of 56-88% with complete remissions in the range of 9-58% are attainable but relapse occurs predominantly within 20 months. At present there is no evidence that any conventional regimen is curative. Prospective multicenter studies are mandatory to overcome this therapeutic dilemma. Patients suitable for some form of maintenance or consolidation therapy should initially be treated intensively by anthracycline-containing regimens. Whether maintenance with interferon or intermittent chemotherapy including new agents, like purine analogues or (un)conjugated monoclonal antibodies are able to influence overall survival is a matter of (ongoing) investigations. Further experimental approaches arise from antisense oligonucleotides or ribozymes blocking the overexpression of bcl-1 especially in this lymphoma entity. At present high-dose myeloablative consolidation radiochemotherapy followed by stem cell rescue in first remission seems to be the most attractive option in younger patients.
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PMID:Mantle cell lymphoma: diagnostic criteria, clinical aspects and therapeutic problems. 917 43

Mantle-cell lymphoma comprises 2%-10% of all non-Hodgkin's lymphomas (NHLs). Patients present with generalized disease, and have a poor prognosis. Three different histologic patterns (mantle zone, nodular, and diffuse) and three different cytological variants (classical, blastic, and pleomorphic) have been described. The phenotype (strong surface IgM, CD5+, CD10-, CD23-, cyclin D1+ and B-cell markers+) is remarkably constant. Dependent on the methods used (PCR, Southern blot analysis, and cytogenetics) a t(11;14) can be detected in approximately 35%-66% of cases. Using FISH analysis, possibly almost all cyclin D1-expressing MCLs carry this translocation, indicating that a substantial part of these translocations are missed by conventional methods. This has been confirmed by DNA fiber FISH analysis by which the breakpoints could be accurately mapped over a 220 kb region centromeric of the cyclin D1 gene. Additional genetic abnormalities involve breakpoints and deletion at the 3' end of the cyclin D1 gene, numerical chromosomal aberrations, mutations in p53, and deletions of p16. These may be associated with tumor progression. Owing to the translocation t(11;14), the cyclin D1 gene is activated. At the RNA level, approximately 90% of MCLs show overexpression. This corroborates immunohistochemistry on paraffin tissue sections. Since expression of cyclin D1 in normal lymphoid cells is very low to undetectable, and only hairy-cell leukemia and very few other B-cell lymphomas show expression, immunohistochemistry for cyclin D1 provides an excellent marker for MCL. In hairy-cell leukemia, expression is moderate and cannot be explained by chromosomal translocation.
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PMID:Bcl-1/cyclin D1 in malignant lymphoma. 920 53

We used a new antibody (NCL-CD5-4C7) immunoreactive for CD5-positive cells in paraffin-embedded tissue, with the microwave antigen retrieval method, to analyze a number of well-characterized cases of B-cell and T-cell non-Hodgkin's lymphomas whose CD5 immunoreactivity was documented by immunohistochemical analysis performed on frozen sections and/or flow cytometric immunophenotypic analysis of neoplastic cell suspensions. In all of the cases included in the study, small, reactive T lymphocytes within histologic sections were strongly positive for CD5 and served as an internal positive control. All CD5-positive T-cell non-Hodgkin's lymphomas (13 [100%] of 13) from several histologic subgroups, were immunoreactive for CD5 in paraffin sections, although 4 of 13 exhibited weak or limited staining of neoplastic cells. The majority of cases of B-cell small lymphocytic lymphoma/chronic lymphocytic leukemia (SLL/CLL) (13 [81%] of 16) and mantle cell lymphoma (14 [93%] of 15), both B-cell lymphoproliferative disorders that are immunoreactive for CD5, were immunoreactive for CD5 in paraffin sections, although 5 of 13 cases of SLL/CLL and 6 of 14 cases of mantle cell lymphoma exhibited weak and/or limited staining of neoplastic cells. Other B-cell non-Hodgkin's lymphomas of various subtypes, including marginal zone, follicular, diffuse large cell, and lymphoblastic types, were nonreactive for CD5 in paraffin sections, as expected. CD5 antibody NCL-CD5-4C7 should be useful for the routine characterization of suspected T-cell and B-cell lymphoproliferative disorders when only paraffin-embedded tissue is available for immunophenotypic analysis.
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PMID:Usefulness of a new CD5 antibody for the diagnosis of T-cell and B-cell lymphoproliferative disorders in paraffin sections. 931 Sep 47

In the present study we examined by Southern blot analysis the presence of deletions and rearrangements of the p16 tumor-suppressor gene in B cell non-Hodgkin's lymphomas (NHLs) in order to determine whether or not these changes can be related to a particular histological subtype and the different clinico-biological and prognostic characteristics of the disease. 103 untreated patients were enrolled in the study. Seven cases displayed alterations in the p16 gene: four cases with homozygous deletions and three with gene rearrangement. The presence of these abnormalities did not correlate with any specific histological subtype: three cases were small lymphocytic lymphomas (two of them reclassified as mantle cell lymphoma on the basis of the REAL classification), two diffuse large cell lymphomas and two small non-cleaved cell lymphomas (one of them considered to be a Burkitt-like lymphoma according to the REAL). These seven cases showed a trend towards worse prognostic indicators than the remaining patients, and this was confirmed in the survival analysis, since the presence of p16 gene abnormalities was associated with a shorter survival (10 vs 81 months, P = 0.0006). In the multivariate analysis, p16 abnormalities were selected as an independent prognostic factor together with the LDH and beta2-microglobulin. These findings support a role for the p16 gene in the pathogenesis of B cell NHLs and suggest an association of p16 abnormalities with aggressive forms of the disease that could be useful to predict the prognosis of patients.
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PMID:Deletions and rearrangements of cyclin-dependent kinase 4 inhibitor gene p16 are associated with poor prognosis in B cell non-Hodgkin's lymphomas. 936 26

The cell cycle regulatory protein cyclin D1 is essential for G1-S phase transition in several epithelial and mesenchymal tissues but is apparently not essential in normal mature B cells. An overexpression of cyclin D1 is induced by the chromosomal translocation t(11;14)(q13;q32), which characterizes non-Hodgkin's lymphomas (NHLs) of mantle cell type. We studied 26 cases of mantle cell lymphoma (MCL) for the expression of cyclins D1 and D3. A total of 23 lymphomas showed a nuclear staining for cyclin D1, whereas reactive B cells of residual germinal centers were constantly negative. When compared with cyclin D3, an inverse staining pattern emerged. Whereas the B cells of residual germinal centers reacted strongly positive for cyclin D3, there was low or missing expression of cyclin D3 in MCL cells. In other B-cell lymphomas (n = 55), including chronic lymphocytic leukemia, low-grade lymphomas of mucosa-associated lymphatic tissue, follicular lymphomas, and diffuse large B-cell lymphomas, no cyclin D1 expression could be detected and 89% of these cases displayed cyclin D3 positivity. Lymphoma cell lines harboring the t(11;14) showed cyclin D1 protein but no or very low levels of cyclin D3; three other B-cell lines, a T-cell line, and peripheral blood lymphocytes strongly expressed cyclin D3 and reacted negatively for cyclin D1. We conclude that the chromosomal translocation t(11;14) leads to an abnormal protein expression of cyclin D1 in the tumor cells of MCL and induces a consecutive downregulation of cyclin D3. In contrast to other B-NHLs, cyclin D1 and D3 expression in MCL is not related to the growth fraction.
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PMID:Cyclin D1 expression in mantle cell lymphoma is accompanied by downregulation of cyclin D3 and is not related to the proliferative activity. 937 97

Chromosome aberrations affecting 3q27 are among the most frequent non-random abnormalities in non-Hodgkin's lymphomas (NHL), especially the diffuse, large cell type. Recently, an association between BCL6 rearrangement and frequent extranodal lesions, rare bone marrow infiltration and a favorable clinical outcome was reported. We performed molecular studies of the BCL6 gene in 54 patients with NHL. Twelve patients (22%) with rearranged BCL6 genes were selected for histological, clinical, molecular, and cytogenetic studies. Ten of these cases were diffuse, large cell type lymphoma, one a follicular lymphoma, and one a mantle cell lymphoma (MCL). All cases were of the B-cell type and this is the first time a rearranged BCL6 gene has been found in an MCL. Cytogenetic data for 10 cases were available and the partner sites of the 3q27 translocation were determined in 7 of 10 patients. These locations were variable, including 6p21.3, 9p22, and 14q11 in addition to the immunoglobulin loci 14q32 (IGH), 2p12 (IGK), and 22q11 (IGL). The heterogeneity in partner sites is distinct from other lymphoma subgroups and may suggest that the genetic events are not uniform among patients with BCL6 rearrangements.
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PMID:Rearrangements of the BCL6 gene and chromosome aberrations affecting 3q27 in 54 patients with non-Hodgkin's lymphoma. 940 30

The indolent B-cell non-Hodgkin's lymphomas are a diverse group of disorders that differ markedly with respect to presenting features and natural history. This article reviews entities that have generally been encompassed under the category of indolent lymphomas in various classifications, including the Working Formulation, although many were not specifically identified or labeled as separate entities. These include small-lymphocytic lymphoma (SLL), lymphoplasmacytoid lymphoma, the follicle center cell lymphomas, mantle cell lymphoma, and nodal and extranodal marginal zone lymphomas, including mucosa-associated lymphoid tissue (MALT) lymphoma. There is still a great deal to be learned about the basic biology and treatment of these disorders. Numerous variables influence the type of management used for each individual case, including the disease entity and stage, symptoms and real or threatened organ dysfunction, patient age, and medical condition, as well as the preferences of the patient and practitioner. Unfortunately, because of the inadequacy of current treatment, the majority of patients with indolent lymphoma will not be cured. Thus, continued investigation in the laboratory and through carefully designed clinical trials is essential.
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PMID:Indolent B-cell non-Hodgkin's lymphomas. 943 91

The molecular mechanisms underlying the pathogenesis of aggressive lymphomas and the histological transformation of indolent variants are not well known. To determine the role of p16(INK4a) gene alterations in the pathogenesis of non-Hodgkin's lymphomas (NHLs) and the histological progression of indolent variants, we have analyzed the expression, deletions, and mutations of this gene in a series of 112 NHLs. Hypermethylation of the gene was also examined in a subset of tumors with lack of protein expression but without mutations or deletions of the gene. p16(INK4a) gene alterations were detected in 3 out of 64 (5%) indolent lymphomas but in 16 out of 48 (33%) primary or transformed aggressive variants. In the low-grade tumors, p16(INK4a) alterations were detected in 1 (4%) chronic lymphocytic leukemia (hemizygous missense mutation), 1 (6%) follicular lymphoma (homozygous deletion), and 1 (5%) typical mantle cell lymphoma (homozygous deletion). The two later cases followed an aggressive clinical evolution. In the aggressive tumors, p16(INK4a) gene alterations were observed in 2 (29%) Richter's syndromes (2 homozygous deletions), 3 (33%) transformed follicular lymphomas (1 homozygous deletion and 2 nonsense mutations), 3 (43%) blastoid mantle cell lymphomas (2 homozygous and 1 hemizygous deletions), 5 (28%) de novo large-cell lymphomas (1 homozygous deletion and 4 hypermethylations), 2 lymphoblastic lymphomas (2 homozygous deletions), and 1 of 2 anaplastic large cell lymphomas (hypermethylation). Protein expression was lost in all tumors with p16(INK4a) alterations except in the typical chronic lymphocytic leukemia (CLL) with hemizygous point mutation. Sequential samples of the indolent and transformed phase of three cases showed the presence of p16(INK4a) deletions in the Richter's syndrome but not in the CLL component of two cases, whereas in a follicular lymphoma the deletion was present in both the follicular tumor and in the diffuse large-cell lymphoma. In conclusion, these findings indicate that p16(INK4a) gene alterations are a relatively infrequent phenomenon in NHLs. However, deletions, mutations, and hypermethylation of the gene with loss of protein expression are associated with aggressive tumors and they may also participate in the histological progression of indolent lymphomas.
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PMID:p16(INK4a) gene inactivation by deletions, mutations, and hypermethylation is associated with transformed and aggressive variants of non-Hodgkin's lymphomas. 953 9


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