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Query: UMLS:C0079731 (
B-cell lymphoma
)
16,671
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Group I Burkitt lymphoma (BL) cell lines, which retain the original biopsy phenotype, have been shown to enter apoptosis in response to a number of external stimuli including serum deprivation, thermal shock, addition of calcium ionophore, and ligation of surface immunoglobulin (Ig) by antibody. Transforming growth factor-beta 1 (TGF beta 1) is known to cause growth arrest in BL lines. Here we show that while it is by itself capable of promoting some degree of apoptosis in group IBL cells, TGF beta 1 cooperates with anti-immunoglobulin to this end. Trimeric soluble recombinant human CD40 ligand (sCD40L) was able to inhibit apoptosis induced by the combination of agonists to some degree, but such rescue proved to be short-lived. Both TGF beta 1 and anti-Ig individually caused BL cells to undergo growth arrest at the G1 phase of cell cycle before their entry into apoptosis: the consequence of sCD40L addition was to maintain the cells in cycle for longer. No induction of the apoptosis-protecting gene,
bcl-2
, occurred in the presence of sCD40L. These findings are discussed, particularly highlighting the relationship existing between survival and the cell cycle. The strong cooperative effects observed between anti-Ig and TGF beta 1 in promoting apoptosis and the inability of CD40 to signal for long-term rescue raise the potential for a novel therapeutic attack on
B-cell lymphoma
.
...
PMID:Transforming growth factor-beta 1 cooperates with anti-immunoglobulin for the induction of apoptosis in group I (biopsy-like) Burkitt lymphoma cell lines. 856 41
Resection specimens from 83 patients with primary gastric lymphoma (PGL) of B cell phenotype at stage IE and at stage IIE according to the Ann Arbor classification were investigated. Histologically, these lymphomas could be divided into four types: Type I lesions (n = 24) were entirely made up of MALT lymphoma; Type II lesions (n = 13) were predominantly MALT lymphoma containing one to a few foci of high-grade
B cell lymphoma
; Type III lesions (n = 22) consisted largely of high-grade lymphoma with small areas of low-grade MALT lymphoma; and Type IV lesions (n = 24) were pure high-grade
B cell lymphoma
, mostly of the large cell type. All patients had undergone primary gastric resection, and 14 received additional chemotherapy (n = 12), or both chemotherapy and radiotherapy (n = 2). The survival probability was significantly higher for Types I and II lymphomas than for Types III and IV tumors (P < 0.05 by the generalized Wilcoxon test). According to The General Rules for the Gastric Cancer Study by the Japanese Research Society for Gastric Cancer, the stage of disease showed a clear distinction between each of them (P < 0.01 by the generalized Wilcoxon test). This staging method seemed to serve well as a prognostic indicator. The histological typing of the PGL of the present series also seemed to correlate with the gross appearance, pathologic stage and prognosis. Furthermore, the expression of cyclin D1,
bcl-2
and p53 protein, and PCNA was immunohistochemically investigated in 42 cases of the present series. Most of the low-grade PGL (Types I and II) had less than 60% PCNA-positive cells, whereas the high-grade PGL (Types III and IV) had more than 60% positive cells. In a study for cyclin D1 protein, no cases showed the nuclear staining pattern characteristic for mantle cell lymphoma, and the cytoplasmic staining frequently observed in the node-based large
B cell lymphoma
was seldom identified in the PGL. This discrepancy might suggest a lineage difference among the morphologically similar, but site-different, lymphomas. On the other hand,
bcl-2
protein overexpression was almost equal in frequency between the gastric and node-based high-grade B cell lymphomas. This is in contrast to the reports from Western countries, in which the majority of high-grade gastric tumors were
bcl-2
negative.
...
PMID:Clinicopathologic study of primary gastric lymphoma of B cell phenotype with special reference to low-grade B cell lymphoma of mucosa-associated lymphoid tissue among the Japanese. 858 Nov 46
The expression of intercellular adhesion molecule 1 (ICAM-1), a molecule pivotal in many inflammatory and immune paracrine interactions, has been highly correlated with malignant melanoma (MM) progression. Because numerous parallels exist between tissues of neural crest origin and the immune system in the regulation of postmitotic cell survival, ICAM-1 expression was studied in MM and compared with that of
B-cell lymphoma
/leukemia 2 protein (
bcl-2
oncoprotein), an important regulator in prolonging lymphoid cell survival by blocking programmed cell death. Frozen sections from 33 cases were studied by immunoperoxidase techniques: 14 primary MM (five in situ), nine metastatic MM (one epidermotropic), four melanocytic nevi, and six normal skin controls. The percentages of the cells that stained and their intensities (0-4+) were graded. Both ICAM-1 (90%, 3-4+) and
bcl-2
(95%, 2-4+) were strongly expressed in all nine metastases, including the epidermotropic disease extension. Bcl-2 strongly decorated the tumor cells in all 14 cases of primary MM (80%, 2-4+); in the five in situ MM,
bcl-2
stained the atypical melanocytes at the dermal-epidermal junction (DEJ) and throughout the epidermis (75%, 1-2+). In contrast, ICAM-1 was negative in the in situ MM. ICAM-1 expression became strong (85%, 2-4+) in the dermal component of early invasive disease. Both ICAM-1 and
bcl-2
were expressed in melanocytic nevi, decreasing in intensity deep within the dermis as the nevus cells senesced ("matured"). Only
bcl-2
was expressed in the normal melanocytes of the six skin controls. These data show that
bcl-2
is constitutively expressed in normal melanocytes and melanocytic nevi and persists in the transformed cells of early and late MM. ICAM-1 is expressed only after dermal involvement occurs, both in melanocytic nevi and in invasive MM; it persists in metastatic disease. The coexpression of
bcl-2
and ICAM-1 demonstrates another similarity between the immune and neural crest systems, but it does not define or necessarily imply any functional interaction between the two proteins. The intercellular relationship of these two molecules, if any, remains to be investigated.
...
PMID:Intercellular adhesion molecule 1 (ICAM-1) and bcl-2 are differentially expressed in early evolving malignant melanoma. 859 46
The immunohistochemical expression of
bcl-2
and p53 proteins was evaluated in formalin-fixed, paraffin-embedded surgical specimens from 212 patients with primary gastric lymphoma.
bcl-2
protein was found to be expressed in 145 specimens (68%). Among the 179 specimens with
B-cell lymphoma
of mucosa-associated lymphoid tissue (MALT),
bcl-2
positivity decreased significantly as the histological grade advanced;
bcl-2
was expressed in 93% of low-grade tumors, 88% of mixed-grade (low-grade with a focal high-grade component) tumors, and 44% of high-grade tumors (Cochran's linear trend test; P<.001). p53 protein expression was detected in 43 of 212 cases (20%). Among the B-cell MALT lymphomas, p53 positivity increased significantly as the histological grade advanced; p53 was expressed in 6% of low-grade tumors, 12% of mixed-grade tumors, and 31% of high-grade tumors (Cochran's linear trend test; P<.001). An inverse correlation was observed between the expression of
bcl-2
and p53 in all 212 lymphomas (gamma = -0.531; P<.05) as well as in all 179 B-cell MALT lymphomas (gamma = -0.671; P<.01). Although the
bcl-2
expression did not correlate with the patient survival, the p53 positive cases showed a significantly poorer prognosis compared with the p53 negative cases (log-rank test; P<.05). These results suggest that the expression of
bcl-2
and p53 may, therefore, be associated with the transition from low-grade to high-grade tumors in primary gastric lymphoma.
...
PMID:Inverse correlation between the expression of bcl-2 and p53 proteins in primary gastric lymphoma. 891 40
Splenic marginal zone cell lymphoma (SMZCL) is a recently described clinicopathologic entity, that is reported to overlap with splenic
B-cell lymphoma
with villous lymphocytes. The authors describe the clinicopathologic, immunophenotypic, and molecular findings in five cases of SMZCL. There were two males and three females, with a mean age of 68.4 years, who presented with peripheral blood cytopenias and splenomegaly. One patient had an absolute lymphocytosis with many villous lymphocytes. With clinical follow-up of 9 to 37 months, two patients are alive and three patients died of unrelated causes. Splenectomy was done in each patient and the spleens were large, 970-2,400 g. Histologically, the SMZCLs preferentially replaced the marginal and mantle zones with partial or complete replacement of germinal centers in the white pump. The neoplastic cells were predominantly small to medium in size with oval or slightly irregular nuclei and relatively abundant pale or eosinophilic cytoplasm. Immunophenotypic studies demonstrated that the neoplastic cells expressed monotypic immunoglobulin, IgD in four tumors, pan-B-cell antigens, and
bcl-2
. The tumor cells were negative for the CD2, CD3, CD5, CD10, CD11c, CD25, CD35, CD38, CD45RO, and CD68 antigens, and tartrate-resistant acid phosphatase. Southern blot hybridization revealed immunoglobulin gene rearrangements in all tumors. The major breakpoint region of the
bcl-2
gene and the T-cell receptor beta chain gene were in the germline configuration. Polymerase chain reaction studies did not identify the t(14;18) or t(11;14). All cases were negative for p53 protein and single-stranded conformational polymorphism analysis for p53 gene mutations was negative. Our results support the concept that SMZCL is a clinically indolent, low grade
B-cell lymphoma
that probably arises from splenic marginal zone lymphocytes.
...
PMID:Splenic marginal zone cell lymphoma. An immunophenotypic and molecular study of five cases. 860 7
Mutations of p53 have been suggested to be involved in the histologic transformation of follicular lymphoma, but the role of the retinoblastoma (RB) gene, another tumor suppressor gene, in lymphomagenesis has not been established. To determine the roles of these tumor suppressor genes and their relationship with the anti-apoptotic
bcl-2
gene in follicle center lymphoma, the immunohistochemical expression of p53,
bcl-2
, and RB proteins was correlated with cytologic grade in 50 cases of follicular lymphoma, and the results were compared to 23 cases of diffuse large
B-cell lymphoma
. The results showed that only 2 of 25 grade 1 follicular lymphoma were p53-positive compared to 16 of 25 grade 3 cases (P <.0001). A significantly lower number (13 of 25) of grade 3 follicular lymphomas expressed
bcl-2
compared to grade 1 cases (23 of 25) (P <.004). Eight of 14
bcl-2
-negative follicular lymphomas expressed p53, compared with 10 of 36
bcl-2
-positive cases (P = .1). Twenty-four of 25 grade 3 follicular lymphomas showed 2+ to 3+ staining for RB protein compared to 9 of 21 grade 1 cases (P <.0002). Expression of p53 protein correlates significantly with higher cytologic grade in follicular lymphoma. Similar to earlier studies of breast cancer and lymphoma, there appears to be an inverse relationship between p53 and
bcl-2
expression in follicular lymphoma. Inactivation of the retinoblastoma gene does not seem to be involved in the histogenesis of follicle center lymphoma or diffuse large
B-cell lymphoma
.
...
PMID:Immunohistochemical detection of p53, bcl-2, and retinoblastoma proteins in follicular lymphoma. 862 59
Most human follicular B-cell lymphomas are associated with t(14;18) chromosome translocation that joins the
bcl-2
gene with the IgH locus. This hybrid gene causes upregulation of BCL-2 protein expression, endowing cells with survival advantage. Although early BCL-2 overexpression is definitely responsible for immortalization/transformation, its exact role in the overt transformation as well as in the maintenance of the tumor phenotype is not known. The capacity of oligodeoxynucleotides (ODN) to modulate gene expression specifically has been exploited to downregulate the overexpression of BCL-2 protein in the SU-DHL-4 human follicular
B-cell lymphoma
line by the use of sense ODN or antisense ODN or antisense ODN designed to encompass the unique nucleotide sequence in the fusion region of the hybrid transcript. The specific downregulation of the
bcl-2
transcript and of the relevant BCL-2 protein in the treated cells activated programed cell death and inhibited growing cells. The antitumor activity was restricted to the DHL-4 cell line carrying the specific nucleotide sequence at the
bcl-2
/IgH joining region. Thus, DHL-4 lymphoma cells derived from the acute phase of human follicular
B-cell lymphoma
, although endowed with additional activated oncogenes, were growth inhibited by
bcl-2
downregulation with additional activated oncogenes, were growth inhibited by
bcl-2
downregulation in a genetically restricted fashion. The biological activity was exerted exclusively by ODNs synthesized in the sense orientation. The sense ODNs have been proposed to anneal the hybrid
bcl-2
/IgH antisense RNA as identified in this study.
...
PMID:Oligonucleotides induce apoptosis restricted to the t(14;18) DHL-4 cell line. 863 45
Primary mediastinal
B cell lymphoma
(PMBL) is a diffuse large
B cell lymphoma
(DLCL) postulated to arise from noncirculating thymic B lymphocytes. Because of its distinctive clinical and morphological features and putative unique cellular origin, PMBL is generally considered a distinct clinicopathological entity. Little is known, however, about the molecular characteristics of PMBL. Therefore, we analyzed 16 PMBLs for molecular alterations involving the bcl-1,
bcl-2
, bcl-6, c-myc, H-ras, K-ras, N-ras, and p53 genes and for Epstein-Barr virus infection, which are commonly involved in lymphoid neoplasia. Employing a combination of Southern blotting and/or polymerase chain reaction and single-strand conformation polymorphism assays, we detected genetic alterations in 7 of the 16 (44%) PMBLs. Whereas the bcl-6 gene is rearranged in up to 45% of DLCLs, rearrangement of the bcl-6 gene was detected in only 1 of these 16 (6%) PMBLS. Point mutations of the 5' noncoding region of the c-myc gene were demonstrated in 3 other cases (19%), although c-myc gene rearrangements were not seen by Southern blotting. Missense point mutations of the p53 gene were identified in 3 additional PMBLs (19%). Alterations of the bcl-1,
bcl-2
, or ras genes and evidence of Epstein-Barr virus infection were not observed. In conclusion, a variety of molecular lesions occur in PMBLs and may be involved in their pathogenesis. This molecular genetic pattern bears little resemblance to that known for other B cell malignancies, including DLCL. In particular, the infrequent occurrence of bcl-6 gene rearrangement in PMBLs distinguishes them from other DLCLs of B cell origin, suggesting that PMBLs do not represent a distinct subtype of DLCL.
...
PMID:Molecular characterization of primary mediastinal B cell lymphoma. 866 86
Among non-Hodgkin's lymphomas, primary mediastinal large
B-cell lymphoma
(PMLCL) has been considered a separate entity that has specific clinical and histological aspects and a poor prognosis. In this study, we reexamined the clinicopathologic features and the response to current treatment of 141 PMLCL and compare them with 916 nonmediastinal large B-cell lymphomas (NMLCL) recorded in the same period and treated with similar combined chemotherapy. The clinical features of PMLCL at diagnosis were largely homogeneous and distinct from NMLCL, with a predilection for young women (59% with a mean age of 37 years versus 42% with a mean age of 54 years), bulky tumor (77% versus 7%, p < 10(4)), high serum lactic dehydrogenase (LDH) level 76% versus 51%, p < 10(4)), and frequent intrathoracic extension to adjacent organs such as pleura, pericardium, and lung. By contrast, extrathoracic or hematologic dissemination was uncommon (2% of bone marrow involvement versus 17%). All patients had diffuse large B-cell nonimmunoblastic, nonanaplastic lymphomas. Histological analysis of the 141 PMLCL evaluated two common patterns: the presence of large cells with clear cytoplasm (found in 38% of cases) and the presence of fibrosis (marked in 25% of cases). The presence of clear cells or intense fibrosis did not constitute prognostic indicators. Immunologic and molecular analysis assessed the profile of
bcl-2
expression and the presence of Epstein-Barr virus (EBV) in PMLCL: 30% expressed a high level of
bcl-2
protein; EBER RNAs were detected by in situ hybridization in only two of the 41 cases tested. Monotypic light chain restriction could be demonstrated in seven of the 41 PMLCL tested on fixed-section. Treated with polychemotherapy regimens without radiotherapy, 79% of PMLCL patients achieved a complete remission compared with 68% in the NMLCL patient group (p = 0.01). Overall, 3-year survival rates were estimated at 66 and 61%, respectively (p = 0.05), and disease-free survival rates were not significantly different (61 versus 64%). Stratified analysis on the International Prognostic Index (based on age, tumor stage, serum LDH level, and performance status) showed no difference in the overall and disease-free survivals between the two lymphoma groups. In conclusion, PMLCL can be combined with other diffuse large B-cell lymphomas on morphologic grounds; it is not associated with EBV. It responds favorably to treatment and should be managed like other high-grade lymphomas of equivalent histology. However, the uncommon clinical presentation makes it a distinct entity.
...
PMID:Primary mediastinal large B-cell lymphoma. A clinicopathologic study of 141 cases compared with 916 nonmediastinal large B-cell lymphomas, a GELA ("Groupe d'Etude des Lymphomes de l'Adulte") study. 866 37
Cytogenetic, in situ hybridization, and molecular studies were performed in a case of T-cell-rich
B-cell lymphoma
. Demonstration of Ig gene rearrangements for both heavy and light chains confirmed the B-lineage restriction of the neoplastic cell population. Moreover, as expected in B-cell malignancies, all abnormal karyotypes showed a 14q+ chromosome marker involving 14q32. The origin of the extra material on the derivative 14q+, as defined by chromosome painting with a library for chromosome 11, and Southern blotting for c-myc and
bcl-2
rearrangements, remains unknown.
...
PMID:14q+ chromosome marker in a T-cell-rich B-cell lymphoma. 868 94
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