Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P10415 (Bcl-2)
 33,771 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

This study found that oridonin, a natural diterpenoid purified from Rabdosia rubescens, inhibited growth of multiple myeloma (MM; U266, RPMI8226), acute lymphoblastic T-cell leukemia (Jurkat), and adult T-cell leukemia (MT-1) cells with an effective dose that inhibited 50% of target cells (ED50) ranging from 0.75 to 2.7 microg/mL. Terminal deoxynucleotidyltransferase-mediated dUTP nick end labeling staining showed that oridonin caused apoptosis of MT-1 cells in a time-dependent manner. We explored effects of oridonin on antiapoptotic Bcl-2 family members and found that it down-regulated levels of Mcl-1 and BCL-x(L), but not Bcl-2 protein, in both MT-1 and RPMI8226 cells. Further studies found that oridonin inhibited nuclear factor-kappa B (NF-kappa B) DNA-binding activity in these cells as measured by luciferase reporter gene, ELISA-based, and electrophoretic mobility shift assays. Oridonin also blocked tumor necrosis factor-alpha- and lipopolysaccharide-stimulated NF-kappa B activity in Jurkat cells as well as RAW264.7 murine macrophages. Of note, oridonin decreased survival of freshly isolated adult T-cell leukemia (three samples), acute lymphoblastic leukemia (one sample), chronic lymphocytic leukemia (one sample), non-Hodgkin's lymphoma (three samples), and MM (four samples) cells from patients in association with inhibition of NF-kappa B DNA-binding activity. On the other hand, oridonin did not affect survival of normal lymphoid cells from healthy volunteers. Taken together, oridonin might be useful as adjunctive therapy for individuals with lymphoid malignancies, including the lethal disease adult T-cell leukemia.
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PMID:Oridonin, a diterpenoid purified from Rabdosia rubescens, inhibits the proliferation of cells from lymphoid malignancies in association with blockade of the NF-kappa B signal pathways. 1582 31

T-cell/histiocyte-rich large B-cell lymphoma (THRLBCL), a proliferating peripheral B-cell neoplasm, is a morphologic variant of diffuse large B-cell lymphoma (DLBCL), which may be confused with Hodgkin's lymphoma, non-Hodgkin's lymphoma, and reactive lymphadenopathies. Though more recent studies suggested that it might be a distinct clinicopathologic entity and/or a heterogeneous entity with derivation from germinal center B cells, its histogenetic derivation remains controversial. The authors analyzed 30 cases of THRLBCL to further characterize the origin of the neoplastic cells using immunohistochemical and molecular studies for expression of Bcl-6, CD10, and CD138, as well as rearrangements of IgH/bcl-2 genes on paraffin-embedded tissue. Half of the cases (15/30) showed Bcl-6 expression and five cases (19%) showed CD10 expression, but none had CD138 expression (0/20). Only three cases showed coexpression of both Bcl-6 and CD10. Molecular studies performed in 21 cases detected rearrangement of immunoglobulin heavy gene in 18 cases, with none having detectable Bcl-2 gene rearrangement. These data indicate that similar to DLBCL, the cell origin of neoplastic cells in THRLBCL is composed of a heterogeneous group of proliferating peripheral B cells, with only some cases originating from germinal center B cells and others derived from heterogeneous origins. Lack of Bcl-2 gene rearrangements seems to argue against a possible progression from preexisting follicular lymphoma. Thus, the normal counterpart of the neoplastic cells cannot at this time be the sole basis for the subclassification of THRLBCL.
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PMID:T-cell/histiocyte-rich large B-cell lymphoma displays a heterogeneity similar to diffuse large B-cell lymphoma: a clinicopathologic, immunohistochemical, and molecular study of 30 cases. 1589 21

Human mantle cell lymphoma (MCL), an aggressive B cell non-Hodgkin's lymphoma, is characterized by the overexpression of cyclin D1 which plays an essential role in the survival and proliferation of MCL. Because of MCL's resistance to current chemotherapy, novel approaches are needed. Since MCL cells are known to overexpress NF-kappaB regulated gene products (including cyclin D1), we used curcumin, a pharmacologically safe agent, to target NF-kappaB in a variety of MCL cell lines. All four MCL cell lines examined had overexpression of cyclin D1, constitutive active NF-kappaB and IkappaB kinase and phosphorylated forms of IkappaBalpha and p65. This correlated with expression of TNF, IkappaBalpha, Bcl-2, Bcl-xl, COX-2 and IL-6, all regulated by NF-kappaB. On treatment of cells with curcumin, however, downregulated constitutive active NF-kappaB and inhibited the consitutively active IkappaBalpha kinase (IKK), and phosphorylation of IkappaBalpha and p65. Curcumin also inhibited constitutive activation of Akt, needed for IKK activation. Consequently, the expression of all NF-kappaB-regulated gene products, were downregulated by the polyphenol leading to the suppression of proliferation, cell cycle arrest at the G1/S phase of the cell cycle and induction of apoptosis as indicated by caspase activation, PARP cleavage, and annexin V staining. That NF-kappaB activation is directly linked to the proliferation of cells, is also indicated by the observation that peptide derived from the IKK/NEMO-binding domain and p65 suppressed the constitutive active NF-kappaB complex and inhibited the proliferation of MCL cells. Constitutive NF-kappaB activation was found to be due to TNF, as anti-TNF antibodies inhibited both NF-kappaB activation and proliferation of cells. Overall, our results indicate that curcumin inhibits the constitutive NF-kappaB and IKK leading to suppression of expression of NF-kappaB-regulated gene products that results in the suppression of proliferation, cell cycle arrest, and induction of apoptosis in MCL.
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PMID:Curcumin (diferuloylmethane) inhibits constitutive NF-kappaB activation, induces G1/S arrest, suppresses proliferation, and induces apoptosis in mantle cell lymphoma. 1602 83

Plasmablastic lymphoma is an HIV-associated non-Hodgkin's lymphoma that primarily affects the oral cavity and jaws. The purpose of this report is to describe the first case of plasmablastic lymphoma occurring in an HIV-negative, nonimmunocompromised individual, and to review the histopathologic and immunohistochemical phenotype of this lymphoma. Histopathologically, our case exhibited a dense, diffuse lymphocytic infiltrate of noncohesive large lymphocytes with plasmacytoid features. Immunohistochemical analysis revealed positivity for the B-cell marker CD79a, VS38c, Epstein-Barr virus latent membrane protein (LMP), immunoglobulin G (IgG), and lambda light chain restriction. Neoplastic cells were negative for leukocyte common antigen, CD20, CD3, CD10, CD138, Bcl-2, Bcl-6, desmin, actin, EMA, S-100, HMB45, Alk-1, HHV8, IgA, IgM, and cytokeratin. The features of this rare disease are summarized based on a comprehensive review of the epidemiologic, clinical and immunohistochemical findings of previously reported cases.
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PMID:Oral plasmablastic lymphoma in an HIV-negative patient: a case report and review of the literature. 1603 78

Follicular lymphoma (FL) is the second most common non-Hodgkin's lymphoma and generally is incurable. Reliable prognostic markers to differentiate patients who progress rapidly from those who survive for years with indolent disease have not been established. Most cases overexpress Bcl-2, but the pathogenesis of FL remains incompletely understood. To determine whether a proteomic approach could help overcome these obstacles, we procured lymphoid follicles from 20 cases of FL and 15 cases of benign follicular hyperplasia (FH) using laser capture microdissection. Lysates were spotted on reverse-phase protein microarrays and probed with 21 antibodies to proteins in the intrinsic apoptotic pathway, including those specific for posttranslational modifications such as phosphorylation. A panel of three antibodies [phospho-Akt(Ser473), Bcl-2, and cleaved poly(ADP-ribose) polymerase] segregated most cases of FL from FH. Phospho-Akt(Ser473) and Bcl-2 were significantly increased in FL (P = 0.001 and P < 0.0001, respectively). Additionally, the Bcl-2/Bak ratio completely segregated FL from FH. High ratios of Bcl-2/Bak and Bcl-2/Bax were associated with early death from disease with differences in median survival times of 7.3 years (P = 0.0085) and 3.8 years (P = 0.018), respectively. Using protein microarrays, we identified candidate proteins that may signify clinically relevant molecular events in FL. This approach showed significant changes at the posttranslational level, including Akt phosphorylation, and suggested new prognostic markers, including the Bcl-2/Bak and Bcl-2/Bax ratios. Proteomic end points should be incorporated in larger, multicenter trials to validate the clinical utility of these protein microarray findings.
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PMID:Proteomic analysis of apoptotic pathways reveals prognostic factors in follicular lymphoma. 1611 25

Aim-To investigate whether clinical features of non-Hodgkin's lymphomas, at the time of first biopsy, correlate with studies of cell proliferation and cell death as well as with the level of bcl-2 expression.Methods-Bcl-2 expression, determined by immunocytochemistry, was compared with cell proliferation, measured using in situ hybridisation for histone mRNA, and cell death by apoptosis, measured using in situ end labelling for DNA cleavage.Results-Histone mRNA staining gave a labelling index of 30% of cells for reactive germinal centres, 5.2-13.5% of cells for low grade non-Hodgkin's lymphoma and 12.1-50.5% of cells for high grade non-Hodgkin's lymphoma. In situ end labelling gave a labelling index of 5.0-10.0% of cells for reactive germinal centres, 1.0-3.7% of cells for low grade non-Hodgkin's lymphoma and 4.7-13.5% of cells for high grade non-Hodgkin's lymphoma. There was a positive correlation between apoptotic index and proliferation index. More cases of low grade than high grade non-Hodgkin's lymphoma expressed bcl-2. There was no correlation between apoptotic index and bcl-2 expression for high grade non-Hodgkin's lymphoma.Conclusions-The molecular mechanisms controlling cell proliferation and death in non-Hodgkin's lymphoma are complex, probably involving a range of genes, including bcl-2. A better understanding of resistance to cell death is needed if the clinical goal of tailoring cancer treatment to individual tumours is to be achieved.
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PMID:Correlation between apoptosis, proliferation and bcl-2 expression in malignant non-Hodgkin's lymphoma. 1669 87

Diffuse large B-cell lymphoma (DLBCL) is an aggressive lymphoma with a 5-year survival rate of 35%-60%. Various clinical factors included in the International Prognostic Index have failed to identify the patients with DLBCL who will not benefit from the standard R-CHOP (cyclophosphamide/doxorubicin/vincristine/prednisone plus rituximab) treatment regimen. Bcl-2 has been implicated in conferring resistance to chemotherapy in non-Hodgkin's lymphoma and is therefore a candidate prognostic marker in DLBCL. To identify the correlation between Bcl-2 expression and response to rituximab-containing treatment regimens, histologic materials were analyzed from 292 elderly patients with confirmed DLBCL. Of these, 155 patients had received R-CHOP (53%) and 137 had received CHOP (47%). One hundred ninety-three patients (66%) were found to express high levels of Bcl-2 protein in > 50% of the tumor cells. Of the 193 Bcl-2-positive patients, the patients who received R-CHOP had a better 5-year overall rate than patients treated with CHOP (56% vs. 42%; P = 0.01), whereas in the patients with Bcl-2-negative disease, there was no statistically significant difference in the 5-year overall survival rates between the R-CHOP and CHOP regimens (58% vs. 52%; P = 0.6). Therefore, the addition of rituximab to the standard chemotherapy regimen seems to have overcome the Bcl-2-associated resistance to chemotherapy.
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PMID:Bcl-2 gene expression as a predictor of outcome in diffuse large B-cell lymphoma. 1679 75

Studies have shown that BIRC7, a new member of inhibitor of the apoptosis protein family, is expressed in fetal tissues and most solid tumors in humans. However, there are no reported data concerning BIRC7 expression in lymphomas. We investigated the expression of BIRC7, survivin, Bcl-2, Bax, p53 and p170 proteins in 167 cases of non-Hodgkin's lymphoma (NHL) and 10 cases of non-specific lymphadenitis by tissue microarray-based immunohistochemistry. BIRC7 mRNA in three cell lines and 16 cases of NHL were detected by reverse transcriptase-polymerase chain reaction. BIRC7 protein was exhibited in the cytoplasm of cells in 25 (31%) of 80 cases of B-NHLs, 32 (37%) of 87 cases of T-NHLs, and none in non-specific lymphadenitis. The positive rate of BIRC7 was lower than that of survivin in almost all types of NHL with no significant differences, and similar to that of Bcl-2, Bax or p53. There was no correlation of protein expression between BIRC7 and any other detected markers, except p170 in T-NHL (P < 0.001). BIRC7 expression did not correlate with clinic pathologic factors such as sex, age, stage and grade, but overexpression of BIRC7 was positively correlated with aggression of NHL cells (P < 0.05). BIRC7 mRNA expressed in six (38%) of 16 cases of NHLs. BIRC7 mRNA expression was approximately consistent with BIRC7 protein in NHL. Our results indicate that the BIRC7 gene might play a role in the development and aggression of NHL and that the inhibition of BIRC7 expression may be important in NHL treatment.
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PMID:Expression of BIRC7 protein and mRNA in non-Hodgkin's lymphoma. 1684 Feb 3

PCR protocols for immunoglobulin heavy chain (IgH) gene rearrangements amplification make easy the NHL-B identification. In this study we analyzed PCR products by Capillary Electrophoresis (CE) and GeneScan (GS) software, wich offers clear advantages over the conventional methods such as agarose gels (AGGE), characterized by hight rate of false negative and false positive results. We suggested some criteria--not included in previous NHL-B issues--useful to a correct analysis of results in GS. Since 2003, we collected 2,977 samples (2,770 peripheral blood and bone marrow, and 207 tissues) for GS analysis from NHL-B patients. At beginning PCR products were detected by both AGGE and CE. FR2 and FR3 VH regions were amplified by PCR seminested; together with Bcl-6 "housekeeping" gene from the same sample, as marker of DNA quality and PCR efficiency. Bcl-2/IgH and Bcl1/IgH traslocations were also analyzed for follicular and mantle cells lymphomas respectively. Resolution and sensitivity tests, developed with serial diluitions of clonal products in water and in DNA from healthy individuals, showed for GS 1% of resolution limit (3% AGGE) and 0.5% of sensitivity (5% AGGE). Our criteria for correct interpretations of results are: a) use of "house-keeping" gene Bcl-6; b) costant reference scales for hight and molecular weight; c) clonal peak at least twice higher than adiacent peaks; d) position of clonal peak (central or eccentric) as regards to policlonal peaks distributions. e) peaks features for oligoclonal or biallelic rearrangements evaluation. GS is an ideal method for detecting IgH rearrangements and some characteristic traslocations. The precise determination of the size of the PCR product can be used for the minimal residual disease evaluation. Moreover, it allows semi-quantitative resolution of fragments only one base different in size and may be more objective than gel-based methods.
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PMID:[Molecular diagnosis of non-Hodgkin B lymphomas by capillary electrophoresis and Genescan analysis: a molecular pathology laboratory experience]. 1692 87

Gallium nitrate is a metallodrug with clinical efficacy in non-Hodgkin's lymphoma. Its mechanisms of antineoplastic action are not fully understood. In the present study, we investigated the roles of transferrin receptor (TfR) targeting and apoptotic pathways in gallium-induced cell death. Although DoHH2 lymphoma cells displayed a 3-fold lower number of TfRs than CCRF-CEM lymphoma cells, they were 3- to 4-fold more sensitive to gallium nitrate. Despite a lower TfR expression, DoHH2 cells had greater TfR cycling and iron and gallium uptake than CCRF-CEM cells. In other lymphoma cell lines, TfR levels per se did not correlate with gallium sensitivity. Cells incubated with gallium nitrate showed morphologic changes of apoptosis, which were decreased by the caspase inhibitor Z-VAD-FMK and by a Bax-inhibitory peptide. Cells exposed to gallium nitrate released cytochrome c from mitochondria and displayed a dose-dependent increase in caspase-3 activity. An increase in active Bax levels without accompanying changes in Bcl-2 or Bcl-X(L) was seen in cells incubated with gallium nitrate. The endogenous expression of antiapoptotic Bcl-2 was greater in DoHH2 cells than in CCRF-CEM cells, suggesting that endogenous Bcl-2 levels do not correlate with cell sensitivity to gallium nitrate. Gallium-induced apoptosis was enhanced by the proteasome inhibitor bortezomib. Our results suggest that TfR function rather than TfR number is important in gallium targeting to cells and that apoptosis is triggered by gallium through the mitochondrial pathway by activating proapoptotic Bax. Our studies also suggest that the antineoplastic activity of combination gallium nitrate and bortezomib warrants further investigation.
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PMID:Gallium-induced cell death in lymphoma: role of transferrin receptor cycling, involvement of Bax and the mitochondria, and effects of proteasome inhibition. 1712 30


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