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Sample records for bcl process

  1. Advanced process modeling at the BCL smelter: Improving economic and environmental performance

    Science.gov (United States)

    Tripathi, Nagendra; Peek, Edgar; Stroud, Milton

    2011-01-01

    Since 1973 Bamangwato Concessions Limited (BCL) has operated a nickel-copper smelter in Selebi-Phikwe, Botswana. The smelter treats concentrates from local mines and various custom feed concentrates. The nickel throughput capacity of this smelter is constrained by a low nickel feed grade in its primary BCL concentrate. BCL contracted Xstrata Process Support (XPS) to assist in identifying key economic drivers to maximize revenue-generating opportunities. After the disclosure of essential BCL plant performance data XPS developed and utilized advanced metallurgical modeling techniques to identify production bottlenecks, calculate Ni, Cu, and Co recoveries, manage the slag volumes, increase the custom feed capacity, and perform various feasibility analyses for key unit process operations in the BCL smelter. The methodology for developing the process model and its application in contributing to the economic bottom line are outlined in this paper.

  2. Time-Resolved Quantum Cascade Laser Absorption Spectroscopy of Pulsed Plasma Assisted Chemical Vapor Deposition Processes Containing BCl3

    Science.gov (United States)

    Lang, Norbert; Hempel, Frank; Strämke, Siegfried; Röpcke, Jürgen

    2011-08-01

    In situ measurements are reported giving insight into the plasma chemical conversion of the precursor BCl3 in industrial applications of boriding plasmas. For the online monitoring of its ground state concentration, quantum cascade laser absorption spectroscopy (QCLAS) in the mid-infrared spectral range was applied in a plasma assisted chemical vapor deposition (PACVD) reactor. A compact quantum cascade laser measurement and control system (Q-MACS) was developed to allow a flexible and completely dust-sealed optical coupling to the reactor chamber of an industrial plasma surface modification system. The process under the study was a pulsed DC plasma with periodically injected BCl3 at 200 Pa. A synchronization of the Q-MACS with the process control unit enabled an insight into individual process cycles with a sensitivity of 10-6 cm-1·Hz-1/2. Different fragmentation rates of the precursor were found during an individual process cycle. The detected BCl3 concentrations were in the order of 1014 molecules·cm-3. The reported results of in situ monitoring with QCLAS demonstrate the potential for effective optimization procedures in industrial PACVD processes.

  3. BCL-2--general considerations.

    Science.gov (United States)

    Moldoveanu, E; Stoian, I; Voinea, L; Marta, D; Popescu, L M

    1998-01-01

    BCL-2 protein is a oncoprotein considered to have an important role in the regulation of programmed cell death--apoptosis. The intracellular localization, the relation with other oncoproteins, the antioxidant function and the pathological implications are discussed.

  4. Illegitimate V(D)J recombination-mediated deletions in Notch1 and Bcl11b are not sufficient for extensive clonal expansion and show minimal age or sex bias in frequency or junctional processing

    Energy Technology Data Exchange (ETDEWEB)

    Champagne, Devin P., E-mail: devin.champagne@uvm.edu; Shockett, Penny E., E-mail: pshockett@selu.edu

    2014-03-15

    Highlights: • Examines illegitimate V(D)J deletion junctions in Notch1 and Bcl11b. • Suggests little influence of deletions alone on clonal outgrowth in wild-type mice. • No age or sex biases in frequency, clonality, or junctional processing observed. • Contrasts with previous results at TCRβ and HPRT1 loci. • Deletions in Bcl11b may be tolerated more easily than those in Notch1. - Abstract: Illegitimate V(D)J recombination at oncogenes and tumor suppressor genes is implicated in formation of several T cell malignancies. Notch1 and Bcl11b, genes involved in developing T cell specification, selection, proliferation, and survival, were previously shown to contain hotspots for deletional illegitimate V(D)J recombination associated with radiation-induced thymic lymphoma. Interestingly, these deletions were also observed in wild-type animals. In this study, we conducted frequency, clonality, and junctional processing analyses of Notch1 and Bcl11b deletions during mouse development and compared results to published analyses of authentic V(D)J rearrangements at the T cell receptor beta (TCRβ) locus and illegitimate V(D)J deletions observed at the human, nonimmune HPRT1 locus not involved in T cell malignancies. We detect deletions in Notch1 and Bcl11b in thymic and splenic T cell populations, consistent with cells bearing deletions in the circulating lymphocyte pool. Deletions in thymus can occur in utero, increase in frequency between fetal and postnatal stages, are detected at all ages examined between fetal and 7 months, exhibit only limited clonality (contrasting with previous results in radiation-sensitive mouse strains), and consistent with previous reports are more frequent in Bcl11b, partially explained by relatively high Recombination Signal Information Content (RIC) scores. Deletion junctions in Bcl11b exhibit greater germline nucleotide loss, while in Notch1 palindromic (P) nucleotides are more abundant, although average P nucleotide length is

  5. Early diagnostic value of Bcl-3 localization in colorectal cancer

    International Nuclear Information System (INIS)

    Saamarthy, Karunakar; Björner, Sofie; Johansson, Martin; Landberg, Göran; Massoumi, Ramin; Jirström, Karin; Masoumi, Katarzyna Chmielarska

    2015-01-01

    B-cell leukemia 3 (Bcl-3) is a member of the inhibitor of κB family, which regulates a wide range of biological processes by functioning as a transcriptional activator or as a repressor of target genes. Elevated expression, sustained nuclear accumulation, and uncontrolled activation of Bcl-3 causes increased cellular proliferation or survival, dependent on the tissue and type of stimuli. We retrospectively reviewed patients who were diagnosed with colorectal cancer at Skåne University Hospital in Malmö between 1st of January 1990 and 31st of December 1991. Bcl-3 localization in colorectal cancer was assessed by immunohistochemistry on tissue microarray and freshly isolated colon from patients. Correlation between Bcl-3 localization and clinicopathological parameters of the cohort were evaluated using the Spearman rank-order correlation coefficient. In addition, Bcl-3 expression and localization in colon adenocarcinoma cells were analysed by western blot, immunohistochemistry and subcellular fractionation separately. We found that Bcl-3 was mainly localized in the cytoplasm in the tumour tissue isolated from colon cancer patients. Normal colon samples from the same patients showed Bcl-3 localization in the nucleus. In three out of six colon cancer cell lines, we detected elevated levels of Bcl-3. In these cell lines Bcl-3 was accumulated in the cytosol. We confirmed these findings by analysing Bcl-3 localization in a colon tissue micro array consisting of 270 cases. In these samples Bcl-3 localization correlated with the proliferation marker Ki-67, but not with the apoptotic marker Caspase 3. These findings indicate that analysis of the subcellular localization of Bcl-3 could be a potential-early diagnostic marker in colon cancer

  6. The Bcl-2 Family in Host-Virus Interactions.

    Science.gov (United States)

    Kvansakul, Marc; Caria, Sofia; Hinds, Mark G

    2017-10-06

    Members of the B cell lymphoma-2 (Bcl-2) family are pivotal arbiters of mitochondrially mediated apoptosis, a process of fundamental importance during tissue development, homeostasis, and disease. At the structural and mechanistic level, the mammalian members of the Bcl-2 family are increasingly well understood, with their interplay ultimately deciding the fate of a cell. Dysregulation of Bcl-2-mediated apoptosis underlies a plethora of diseases, and numerous viruses have acquired homologs of Bcl-2 to subvert host cell apoptosis and autophagy to prevent premature death of an infected cell. Here we review the structural biology, interactions, and mechanisms of action of virus-encoded Bcl-2 proteins, and how they impact on host-virus interactions to ultimately enable successful establishment and propagation of viral infections.

  7. Functions of BCL-XL at the Interface between Cell Death and Metabolism

    Directory of Open Access Journals (Sweden)

    Judith Michels

    2013-01-01

    Full Text Available The BCL-2 homolog BCL-XL, one of the two protein products of BCL2L1, has originally been characterized for its prominent prosurvival functions. Similar to BCL-2, BCL-XL binds to its multidomain proapoptotic counterparts BAX and BAK, hence preventing the formation of lethal pores in the mitochondrial outer membrane, as well as to multiple BH3-only proteins, thus interrupting apical proapoptotic signals. In addition, BCL-XL has been suggested to exert cytoprotective functions by sequestering a cytosolic pool of the pro-apoptotic transcription factor p53 and by binding to the voltage-dependent anion channel 1 (VDAC1, thereby inhibiting the so-called mitochondrial permeability transition (MPT. Thus, BCL-XL appears to play a prominent role in the regulation of multiple distinct types of cell death, including apoptosis and regulated necrosis. More recently, great attention has been given to the cell death-unrelated functions of BCL-2-like proteins. In particular, BCL-XL has been shown to modulate a number of pathophysiological processes, including—but not limited to—mitochondrial ATP synthesis, protein acetylation, autophagy and mitosis. In this short review article, we will discuss the functions of BCL-XL at the interface between cell death and metabolism.

  8. Grouper iridovirus GIV66 is a Bcl-2 protein that inhibits apoptosis by exclusively sequestering Bim.

    Science.gov (United States)

    Banjara, Suresh; Mao, Jiahao; Ryan, Timothy M; Caria, Sofia; Kvansakul, Marc

    2018-04-13

    Programmed cell death or apoptosis is a critical mechanism for the controlled removal of damaged or infected cells, and proteins of the Bcl-2 family are important arbiters of this process. Viruses have been shown to encode functional and structural homologs of Bcl-2 to counter premature host-cell apoptosis and ensure viral proliferation or survival. Grouper iridovirus (GIV) is a large DNA virus belonging to the Iridoviridae family and harbors GIV66, a putative Bcl-2-like protein and mitochondrially localized apoptosis inhibitor. However, the molecular and structural basis of GIV66-mediated apoptosis inhibition is currently not understood. To gain insight into GIV66's mechanism of action, we systematically evaluated its ability to bind peptides spanning the BH3 domain of pro-apoptotic Bcl-2 family members. Our results revealed that GIV66 harbors an unusually high level of specificity for pro-apoptotic Bcl-2 and displays affinity only for Bcl-2-like 11 (Bcl2L11 or Bim). Using crystal structures of both apo-GIV66 and GIV66 bound to the BH3 domain from Bim, we unexpectedly found that GIV66 forms dimers via an interface that results in occluded access to the canonical Bcl-2 ligand-binding groove, which breaks apart upon Bim binding. This observation suggests that GIV66 dimerization may affect GIV66's ability to bind host pro-death Bcl-2 proteins and enables highly targeted virus-directed suppression of host apoptosis signaling. Our findings provide a mechanistic understanding for the potent anti-apoptotic activity of GIV66 by identifying it as the first single-specificity, pro-survival Bcl-2 protein and identifying a pivotal role of Bim in GIV-mediated inhibition of apoptosis. © 2018 by The American Society for Biochemistry and Molecular Biology, Inc.

  9. Bcl-2 and Bcl-xL overexpression inhibits cytochrome c release, activation of multiple caspases, and virus release following coxsackievirus B3 infection

    International Nuclear Information System (INIS)

    Carthy, Christopher M.; Yanagawa, Bobby; Luo Honglin; Granville, David J.; Yang, Decheng; Cheung, Paul; Cheung, Caroline; Esfandiarei, Mitra; Rudin, Charles M.; Thompson, Craig B.; Hunt, David W.C.; McManus, Bruce M.

    2003-01-01

    Coxsackievirus B3, a cytopathic virus in the family Picornaviridae, induces degenerative changes in host cell morphology. Here we demonstrate cytochrome c release and caspases-2, -3, -6, -7, -8, and -9 processing. Enforced Bcl-2 and Bcl-xL expression markedly reduced release of cytochrome c, presentation of the mitochondrial epitope 7A6, and depressed caspase activation following infection. In comparison, cell death using TRAIL ligand caused caspase-8 processing prior to cytochrome c release and executioner caspases and cell death was only partially rescued by Bcl-2 and Bcl-xL overexpression. Disruption of the mitochondrial inner membrane potential following CVB3 infection was not inhibited by zVAD.fmk treatment. Bcl-2 or Bcl-xL overexpression or zVAD.fmk treatment delayed the loss of host cell viability and decreased progeny virus release following infection. Our data suggest that mitochondrial release of cytochrome c may be an important early event in caspase activation in CVB3 infection, and, as such, may contribute to the loss of host-cell viability and progeny virus release

  10. Withaferin A Suppresses Anti-apoptotic BCL2, Bcl-xL, XIAP and ...

    African Journals Online (AJOL)

    apoptotic genes, BCL2, Bcl-xL, XIAP and Survivin), in cervical carcinoma cells. Methods: Annexin V-FITC/propidium iodide (PI) staining was used for the investigation of cell apoptosis. RNA RNeasy Kits was used to isolate RNA and Omniscript ...

  11. DNA rearrangement in human follicular lymphoma can involve the 5' or the 3' region of the bcl-2 gene

    International Nuclear Information System (INIS)

    Tsujimoto, Y.; Bashir, M.M.; Givol, I.; Cossman, J.; Jaffe, E.; Croce, C.M.

    1987-01-01

    In most human lymphomas, the chromosome translocation t(14;18) occurs within two breakpoint clustering regions on chromosome 18, the major one at the 3' untranslated region of the bcl-2 gene and the minor one at 3' of the gene. Analysis of a panel of follicular lymphoma DNAs using probes for the first exon of the bcl-2 gene indicates that DNA rearrangements may also occur 5' to the involved bcl-2 gene. In this case the IgH locus and the bcl-2 gene are found in an order suggesting that an inversion also occurred during the translocation process. The coding region of the bcl-2 gene, however, are left intact in all cases of follicular lymphoma studied to date

  12. The T-ALL related gene BCL11B regulates the initial stages of human T-cell differentiation.

    Science.gov (United States)

    Ha, V L; Luong, A; Li, F; Casero, D; Malvar, J; Kim, Y M; Bhatia, R; Crooks, G M; Parekh, C

    2017-11-01

    The initial stages of T-cell differentiation are characterized by a progressive commitment to the T-cell lineage, a process that involves the loss of alternative (myelo-erythroid, NK, B) lineage potentials. Aberrant differentiation during these stages can result in T-cell acute lymphoblastic leukemia (T-ALL). However, the mechanisms regulating the initial stages of human T-cell differentiation are obscure. Through loss of function studies, we showed BCL11B, a transcription factor recurrently mutated T-ALL, is essential for T-lineage commitment, particularly the repression of NK and myeloid potentials, and the induction of T-lineage genes, during the initial stages of human T-cell differentiation. In gain of function studies, BCL11B inhibited growth of and induced a T-lineage transcriptional program in T-ALL cells. We found previously unknown differentiation stage-specific DNA binding of BCL11B at multiple T-lineage genes; target genes showed BCL11B-dependent expression, suggesting a transcriptional activator role for BCL11B at these genes. Transcriptional analyses revealed differences in the regulatory actions of BCL11B between human and murine thymopoiesis. Our studies show BCL11B is a key regulator of the initial stages of human T-cell differentiation and delineate the BCL11B transcriptional program, enabling the dissection of the underpinnings of normal T-cell differentiation and providing a resource for understanding dysregulations in T-ALL.

  13. BCL2 genotypes and prostate cancer survival

    Energy Technology Data Exchange (ETDEWEB)

    Renner, Wilfried [Medical University of Graz, Clinical Institute of Medical and Chemical Laboratory Diagnostics, Graz (Austria); Langsenlehner, Uwe [GKK Outpatient Department, Division of Internal Medicine, Graz (Austria); Krenn-Pilko, Sabine; Langsenlehner, Tanja [Medical University of Graz, Department of Therapeutic Radiology and Oncology, Graz (Austria); Eder, Petra [University Hospital Wuerzburg, Department of Internal Medicine I, Wuerzburg (Germany)

    2017-06-15

    The antiapoptotic B-cell lymphoma 2 (BCL2) gene is a key player in cancer development and progression. A functional single-nucleotide polymorphism (c.-938C>A, rs2279115) in the inhibitory P2 BCL2 gene promoter has been associated with clinical outcomes in various types of cancer. Aim of the present study was to analyze the role of BCL2-938C>A genotypes in prostate cancer mortality. The association between BCL2-938C>A (rs2279115) genotypes and prostate cancer outcome was studied within the prospective PROCAGENE study comprising 702 prostate cancer patients. During a median follow-up time of 92 months, 120 (17.1%) patients died. A univariate Cox regression model showed a significant association of the CC genotype with reduced cancer-specific survival (CSS; hazard ratio, HR, 2.13, 95% confidence interval, CI, 1.10-4.12; p = 0.024) and overall survival (OS; HR 2.34, 95% CI 1.58-3.47; p < 0.001). In a multivariate Cox regression model including age at diagnosis, risk group, and androgen deprivation therapy, the CC genotype remained a significant predictor of poor CSS (HR 2.05, 95% CI 1.05-3.99; p = 0.034) and OS (HR 2.25, 95% CI 1.51-3.36; p < 0.001). This study provides evidence that the homozygous BCL2-938 CC genotype is associated with OS and C in prostate cancer patients. (orig.) [German] Das antiapoptotische Gen B cell lymphoma 2 (BCL2) spielt eine Schluesselrolle in der Entstehung und Progression von Krebserkrankungen. Ein funktioneller Einzelnukleotid-Polymorphismus (c.-938C>A, rs2279115) im inhibitorischen P2-BCL2-Promotor wurde mit dem klinischen Outcome verschiedener Krebserkrankungen verknuepft. Ziel der vorliegenden Studie war die Untersuchung der Rolle von BCL2-938C>A-Genotypen fuer die Mortalitaet bei Patienten mit Prostatakarzinom. Der Zusammenhang zwischen BCL2-938C>A-Genotypen (rs2279115) und dem Outcome bei Prostatakrebs wurde in der prospektiven PROCAGENE-Studie, die 702 Patienten mit Prostatakarzinom umfasste, untersucht. Waehrend der medianen

  14. Immunogenicity of Bcl-2 in patients with cancer

    DEFF Research Database (Denmark)

    Andersen, Mads Hald; Svane, Inge Marie; Kvistborg, Pia

    2005-01-01

    activities in preclinical models and are currently in several clinical trials. The clinical application of immunotherapy against cancer is rapidly moving forward in multiple areas, including the adoptive transfer of anti-tumor-reactive T cells and the use of "therapeutic" vaccines. The overexpression of Bcl......B-cell lymphoma 2 (Bcl-2) is a pivotal regulator of apoptotic cell death and it is overexpressed in many cancers. Consequently, the Bcl-2 protein is an attractive target for drug design, and Bcl-2-specific antisense oligonucleotides or small-molecule Bcl-2 inhibitors have shown broad anticancer...

  15. Apoptosis in differentiating C2C12 muscle cells selectively targets Bcl-2-deficient myotubes

    Science.gov (United States)

    Schoneich, Christian; Dremina, Elena; Galeva, Nadezhda; Sharov, Victor

    2014-01-01

    Muscle cell apoptosis accompanies normal muscle development and regeneration, as well as degenerative diseases and aging. C2C12 murine myoblast cells represent a common model to study muscle differentiation. Though it was already shown that myogenic differentiation of C2C12 cells is accompanied by enhanced apoptosis in a fraction of cells, either the cell population sensitive to apoptosis or regulatory mechanisms for the apoptotic response are unclear so far. In the current study we characterize apoptotic phenotypes of different types of C2C12 cells at all stages of differentiation, and report here that myotubes of differentiated C2C12 cells with low levels of anti-apoptotic Bcl-2 expression are particularly vulnerable to apoptosis even though they are displaying low levels of pro-apoptotic proteins Bax, Bak and Bad. In contrast, reserve cells exhibit higher levels of Bcl-2 and high resistance to apoptosis. The transfection of proliferating myoblasts with Bcl-2 prior to differentiation did not protect against spontaneous apoptosis accompanying differentiation of C2C12 cell but led to Bcl-2 overexpression in myotubes and to significant protection from apoptotic cell loss caused by exposure to hydrogen peroxide. Overall, our data advocate for a Bcl-2-dependent mechanism of apoptosis in differentiated muscle cells. However, downstream processes for spontaneous and hydrogen peroxide induced apoptosis are not completely similar. Apoptosis in differentiating myoblasts and myotubes is regulated not through interaction of Bcl-2 with pro-apoptotic Bcl-2 family proteins such as Bax, Bak, and Bad. PMID:24129924

  16. Immunogenicity of Bcl-2 in patients with cancer

    DEFF Research Database (Denmark)

    Andersen, Mads Hald; Svane, Inge Marie; Kvistborg, Pia

    2005-01-01

    activities in preclinical models and are currently in several clinical trials. The clinical application of immunotherapy against cancer is rapidly moving forward in multiple areas, including the adoptive transfer of anti-tumor-reactive T cells and the use of "therapeutic" vaccines. The overexpression of Bcl......B-cell lymphoma 2 (Bcl-2) is a pivotal regulator of apoptotic cell death and it is overexpressed in many cancers. Consequently, the Bcl-2 protein is an attractive target for drug design, and Bcl-2-specific antisense oligonucleotides or small-molecule Bcl-2 inhibitors have shown broad anticancer......-2 in cancer and the fact that immune escape by down-regulation or loss of expression of this protein would impair sustained tumor growth makes Bcl-2 a very attractive target for anticancer immunotherapy. Herein, we describe spontaneous T-cell reactivity against Bcl-2 in peripheral blood from...

  17. Analysis list: Bcl6 [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Bcl6 Blood,Liver,Pancreas + mm9 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/targ...et/Bcl6.1.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/target/Bcl6.5.tsv http://dbarchive.biosciencedb...c.jp/kyushu-u/mm9/target/Bcl6.10.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/colo/Bcl6.Blood.tsv,http://dbarchive.bioscience...dbc.jp/kyushu-u/mm9/colo/Bcl6.Liver.tsv,http://dbarchive.bioscience...dbc.jp/kyushu-u/mm9/colo/Bcl6.Pancreas.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/colo/Bloo

  18. Bax, Bcl-2, and Bax/Bcl-2 as prognostic markers in acute myeloid leukemia: are we ready for Bcl-2-directed therapy?

    Science.gov (United States)

    Kulsoom, Bibi; Shamsi, Tahir Sultan; Afsar, Nasir Ali; Memon, Zahida; Ahmed, Nikhat; Hasnain, Syed Nazrul

    2018-01-01

    Many anticancer drugs induce apoptosis in malignant cells, and resistance to apoptosis could lead to suboptimal or no therapeutic benefit. Two cytoplasmic proteins, B-cell lymphoma protein 2 (Bcl-2)-associated X (Bax) and Bcl-2, act as a promoter and an inhibitor of apoptosis, respectively. Both Bax and Bcl-2 as well as their ratio have been regarded as prognostic markers in various cancers. However, conflicting results have been reported. A clear understanding of apoptosis has also become crucial due to reports about anti-Bcl-2 chemotherapy. We explored the relationship of Bax and Bcl-2 gene expression and their ratio with the therapeutic response in acute myeloid leukemia (AML) patients. Bone marrow and/or blood samples from 90 AML patients treated with cytarabine and daunorubicin were included. Expression of Bax and Bcl-2 was determined through real-time polymerase chain reaction by using ΔΔCt method of relative expression. Bax and Bcl-2 expression among marrow and blood samples correlated with each other ( r s =0.5, p <0.01). Although bone marrow expression of Bax and Bcl-2 tended to remain higher among responders (median 1.01 and 0.29, respectively) as compared to non-responders (median 0.66 and 0.24, respectively), the difference failed to reach statistical significance ( U =784.5 and 733; p =0.68 and 0.28, respectively). Conversely, Bax/Bcl-2 ratio was higher among poor responders (median 3.07 vs 1.78), though again failed to reach statistical significance ( U =698.5, p =0.07). Expression of Bax and Bcl-2 does not differ significantly among AML patients treated with cytarabine and daunorubicin in terms of remission, relapse, resistance, overall survival, and disease-free survival, thus questioning the utility of emerging anti-Bcl-2 therapy.

  19. Reconstitution of the anti-apoptotic Bcl-2 protein into lipid membranes and biophysical evidence for its detergent-driven association with the pro-apoptotic Bax protein.

    Directory of Open Access Journals (Sweden)

    Marcus Wallgren

    Full Text Available The anti-apoptotic B-cell CLL/lymphoma-2 (Bcl-2 protein and its counterpart, the pro-apoptotic Bcl-2-associated X protein (Bax, are key players in the regulation of the mitochondrial pathway of apoptosis. However, how they interact at the mitochondrial outer membrane (MOM and there determine whether the cell will live or be sentenced to death remains unknown. Competing models have been presented that describe how Bcl-2 inhibits the cell-killing activity of Bax, which is common in treatment-resistant tumors where Bcl-2 is overexpressed. Some studies suggest that Bcl-2 binds directly to and sequesters Bax, while others suggest an indirect process whereby Bcl-2 blocks BH3-only proteins and prevents them from activating Bax. Here we present the results of a biophysical study in which we investigated the putative interaction of solubilized full-length human Bcl-2 with Bax and the scope for incorporating the former into a native-like lipid environment. Far-UV circular dichroism (CD spectroscopy was used to detect direct Bcl-2-Bax-interactions in the presence of polyoxyethylene-(23-lauryl-ether (Brij-35 detergent at a level below its critical micelle concentration (CMC. Additional surface plasmon resonance (SPR measurements confirmed this observation and revealed a high affinity between the Bax and Bcl-2 proteins. Upon formation of this protein-protein complex, Bax also prevented the binding of antimycin A2 (a known inhibitory ligand of Bcl-2 to the Bcl-2 protein, as fluorescence spectroscopy experiments showed. In addition, Bcl-2 was able to form mixed micelles with Triton X-100 solubilized neutral phospholipids in the presence of high concentrations of Brij-35 (above its CMC. Following detergent removal, the integral membrane protein was found to have been fully reconstituted into a native-like membrane environment, as confirmed by ultracentrifugation and subsequent SDS-PAGE experiments.

  20. A Review on Structures and Functions of Bcl-2 Family Proteins from Homo sapiens.

    Science.gov (United States)

    Sivakumar, Dakshinamurthy; Sivaraman, Thirunavukkarasu

    2016-01-01

    Cancer cells evade apoptosis, which is regulated by proteins of Bcl-2 family in the intrinsic pathways. Numerous experimental three-dimensional (3D) structures of the apoptotic proteins and the proteins bound with small chemical molecules/peptides/proteins have been reported in the literature. In this review article, the 3D structures of the Bcl-2 family proteins from Homo sapiens and as well complex structures of the anti-apoptotic proteins bound with small molecular inhibitors reported in the literature to date have been comprehensively listed out and described in detail. Moreover, the molecular mechanisms by which the Bcl-2 family proteins modulate the apoptotic processes and strategies for designing antagonists to anti-apoptotic proteins have been concisely discussed.

  1. Chemically Induced Degradation of the Oncogenic Transcription Factor BCL6

    Directory of Open Access Journals (Sweden)

    Nina Kerres

    2017-09-01

    Full Text Available The transcription factor BCL6 is a known driver of oncogenesis in lymphoid malignancies, including diffuse large B cell lymphoma (DLBCL. Disruption of its interaction with transcriptional repressors interferes with the oncogenic effects of BCL6. We used a structure-based drug design to develop highly potent compounds that block this interaction. A subset of these inhibitors also causes rapid ubiquitylation and degradation of BCL6 in cells. These compounds display significantly stronger induction of expression of BCL6-repressed genes and anti-proliferative effects than compounds that merely inhibit co-repressor interactions. This work establishes the BTB domain as a highly druggable structure, paving the way for the use of other members of this protein family as drug targets. The magnitude of effects elicited by this class of BCL6-degrading compounds exceeds that of our equipotent non-degrading inhibitors, suggesting opportunities for the development of BCL6-based lymphoma therapeutics.

  2. Evaluation of Bcl-2, Bcl-x and Cleaved Caspase-3 in Malignant Peripheral Nerve Sheath Tumors and Neurofibromas

    Directory of Open Access Journals (Sweden)

    KARIN S. CUNHA

    2013-11-01

    Full Text Available AIMS: To study the expression of Bcl-2, Bcl-x, as well the presence of cleaved caspase-3 in neurofibromas and malignant peripheral nerve sheath tumors. The expression of Bcl-2 and Bcl-x and the presence of cleaved caspase 3 were compared to clinicopathological features of malignant peripheral nerve sheath tumors and their impact on survival rates were also investigated. MATERIALS AND METHODS: The evaluation of Bcl-2, Bcl-x and cleaved caspase-3 was performed by immunohistochemistry using tissue microarrays in 28 malignant peripheral nerve sheath tumors and 38 neurofibromas. Immunoquantification was performed by computerized digital image analysis. CONCLUSIONS: Apoptosis is altered in neurofibromas and mainly in malignant peripheral nerve sheath tumors. High levels of cleaved caspase-3 are more common in tumors with more aggressive histological features and it is associated with lower disease free survival of patients with malignant peripheral nerve sheath tumors.

  3. The BCL11A transcription factor directly activates RAG gene expression and V(D)J recombination.

    Science.gov (United States)

    Lee, Baeck-seung; Dekker, Joseph D; Lee, Bum-kyu; Iyer, Vishwanath R; Sleckman, Barry P; Shaffer, Arthur L; Ippolito, Gregory C; Tucker, Philip W

    2013-05-01

    Recombination-activating gene 1 protein (RAG1) and RAG2 are critical enzymes for initiating variable-diversity-joining (VDJ) segment recombination, an essential process for antigen receptor expression and lymphocyte development. The transcription factor BCL11A is required for B cell development, but its molecular function(s) in B cell fate specification and commitment is unknown. We show here that the major B cell isoform, BCL11A-XL, binds the RAG1 promoter and Erag enhancer to activate RAG1 and RAG2 transcription in pre-B cells. We employed BCL11A overexpression with recombination substrates in a cultured pre-B cell line as well as Cre recombinase-mediated Bcl11a(lox/lox) deletion in explanted murine pre-B cells to demonstrate direct consequences of BCL11A/RAG modulation on V(D)J recombination. We conclude that BCL11A is a critical component of a transcriptional network that regulates B cell fate by controlling V(D)J recombination.

  4. Targeted BCL2 inhibition effectively inhibits neuroblastoma tumour growth

    NARCIS (Netherlands)

    Lamers, Fieke; Schild, Linda; den Hartog, Ilona J. M.; Ebus, Marli E.; Westerhout, Ellen M.; Ora, Ingrid; Koster, Jan; Versteeg, Rogier; Caron, Huib N.; Molenaar, Jan J.

    2012-01-01

    Genomic aberrations of key regulators of the apoptotic pathway have hardly been identified in neuroblastoma. We detected high BCL2 mRNA and protein levels in the majority of neuroblastoma tumours by Affymetrix expression profiling and Tissue Micro Array analysis. This BCL2 mRNA expression is

  5. Immunogenicity of Bcl-2 in patients with cancer

    DEFF Research Database (Denmark)

    Andersen, Mads Hald; Svane, Inge Marie; Kvistborg, Pia

    2005-01-01

    patients suffering from unrelated tumor types (ie, pancreatic cancer, breast cancer, acute myeloid leukemia [AML], and chronic lymphocytic leukemia [CLL]). Additionally, we show that these Bcl-2-reactive T cells are indeed peptide-specific, cytotoxic effector cells. Thus, Bcl-2 may serve as an important...

  6. Ectopic expression of Bcl-2, but not Bcl-xL rescues Ramos B cells from Fas-mediated apoptosis.

    Science.gov (United States)

    Alam, M K; Davison, S; Siddiqui, N; Norton, J D; Murphy, J J

    1997-12-01

    The human Burkitt lymphoma Ramos B cell line can be induced to undergo apoptosis in response to a variety of different agents, including calcium ionophores, anti-immunoglobulin (Ig) and macromolecular synthesis inhibitors. In addition, following up-regulation of the Fas (CD95) surface receptor by CD40 ligation, these cells also become susceptible to apoptosis induction by Fas ligation. We have previously shown that protection from calcium ionophore- and macromolecular synthesis inhibitor-induced apoptosis by CD40 ligation is associated with a rapid up-regulation of Bcl-xL followed by a more moderate and delayed up-regulation of Bcl-2. We show here that overexpression of Bcl-xL, like Bcl-2, protects Ramos cells from apoptosis induction in response to calcium ionophore, anti-Ig and macromolecular synthesis inhibition. However, in contrast to Bcl-2, ectopic overexpression of Bcl-xL does not rescue from Fas-mediated apoptosis. Thus, in Ramos B cells, the Fas apoptotic pathway exhibits differential sensitivity to inhibition by Bcl-2 family members. These findings also suggest that CD40 signaling provides a switch which renders the cells susceptible to Fas-ligand mediated apoptosis through up-regulation of Fas whilst affording protection from anti-Ig-induced apoptosis through up-regulation of Bcl-xL.

  7. Bcl-x(L) expression in vivo in rheumatoid synovium.

    LENUS (Irish Health Repository)

    Busteed, S

    2012-02-03

    To examine the expression of the apoptosis regulatory protein, Bcl-x(L), in the synovium of patients with rheumatoid arthritis (RA) and osteoarthritis (OA). Immunohistochemistry for Bcl-x(L) was carried out on synovial samples from patients with RA and OA. Reverse transcriptase polymerase chain reaction (RT-PCR) and Western blot analysis were performed to qualitatively examine the expression of Bcl-x(L). Bcl-x(L) expression was detected in the lining, endothelium and inflammatory cells of both RA (n=20) and OA (n=10) samples. However, there was significantly more expression in the lining of RA synovium compared to OA (77 vs 61%, p<0.05). Many of the positive cells in the RA subsynovium were noted to be plasma cells. There was a significant correlation between Bcl-x(L) expression and the number of inflammatory cells in the subsynovium of RA and OA patients (r (s)=0.376, p<0.05, n=30). Age and disease duration did not correlate with Bcl-x(L) expression in rheumatoid patients. Bcl-x(L) may play a role in the extended survival of synoviocytes and inflammatory cells in rheumatoid synovium.

  8. BCL11A expression in acute phase chronic myeloid leukemia.

    Science.gov (United States)

    Yin, Jiawei; Zhang, Fan; Tao, Huiquan; Ma, Xiao; Su, Guangsong; Xie, Xiaoli; Xu, Zhongjuan; Zheng, Yanwen; Liu, Hong; He, Chao; Mao, Zhengwei Jenny; Wang, Zhiwei; Chang, Weirong; Gale, Robert Peter; Wu, Depei; Yin, Bin

    2016-08-01

    Chronic myeloid leukemia (CML) has chronic and acute phases. In chronic phase myeloid differentiation is preserved whereas in acute phase myeloid differentiation is blocked. Acute phase CML resembles acute myeloid leukemia (AML). Chronic phase CML is caused by BCR-ABL1. What additional mutation(s) cause transition to acute phase is unknown and may differ in different persons with CML. BCL11A encodes a transcription factor and is aberrantly-expressed in several haematological and solid neoplasms. We analyzed BCL11A mRNA levels in subjects with chronic and acute phase CML. BCL11A transcript levels were increased in subjects with CML in acute phase compared with those in normals and in subjects in chronic phase including some subjects studied in both phases. BCL11A mRNA levels were correlated with percent bone marrow blasts and significantly higher in lymphoid versus myeloid blast crisis. Differentiation of K562 with butyric acid, a CML cell line, decreased BCL11A mRNA levels. Cytology and flow cytometry analyses showed that ectopic expression of BCL11A in K562 cells blocked differentiation. These data suggest BCL11A may operate in transformation of CML from chronic to acute phase in some persons. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Prognostic Importance of Bcl-2 Expression in Colon Cancer

    Directory of Open Access Journals (Sweden)

    Arsenal Alikanoðlu

    2012-09-01

    Full Text Available Aim: TNM classification, that had been established according to pathologic and anatomic characteristics of the lesion , is the most important factor in decision of adjuvant therapy in colon cancer. Despite curative resection, recurrence can ocur with a rate of 20-30% in early stage disease. Therefore efficieny of TNM classification is controversial. In recent years ,significance of molecular characteristics of the tumors besides their anatomic and pathologic characteristics in determining the biological behaviour and response to treatment have been discussed. In our study, relation between expression of Bcl-2 and the other known prognostic factors in colon cancer had been searched. Material and Method: Patients who had been followed up in our clinic were enrolled in this study. Expression of Bcl-2 was searched by immunohistochemical method. Results: A total of 52, 19 (%36.5 female and 33 (%63.5 male patients were enrolled in this study. Bcl-2 expression was found positive in 7 (%13.5 and negative in 45 (%86.5 patients. Statistically no significant relationship was found between Bcl-2 expression and sex, stage, regional lymph node involvement, presence of distant metastasis and histologic grade. Discussion: In our study, although not in a statistical significance, we found that Bcl-2 expression is related to early stage disease. Bcl-2 is a low-priced and easily accessible prognostic marker. We think that establishing expression of Bcl-2 by immunohistohemistry may play a role in determining prognosis of patients with colon cancer.

  10. The roles of Bcl-xL in modulating apoptosis during development of Xenopus laevis

    Directory of Open Access Journals (Sweden)

    Calderon-Segura Maria

    2005-09-01

    Full Text Available Abstract Background Apoptosis is a common and essential aspect of development. It is particularly prevalent in the central nervous system and during remodelling processes such as formation of the digits and in amphibian metamorphosis. Apoptosis, which is dependent upon a balance between pro- and anti-apoptotic factors, also enables the embryo to rid itself of cells damaged by gamma irradiation. In this study, the roles of the anti-apoptotic factor Bcl-xL in protecting cells from apoptosis were examined in Xenopus laevis embryos using transgenesis to overexpress the XR11 gene, which encodes Bcl-xL. The effects on developmental, thyroid hormone-induced and γ-radiation-induced apoptosis in embryos were examined in these transgenic animals. Results Apoptosis was abrogated in XR11 transgenic embryos. However, the transgene did not prevent the apoptotic response of tadpoles to thyroid hormone during metamorphosis. Post-metamorphic XR11 frogs were reared to sexual maturity, thus allowing us to produce second-generation embryos and enabling us to distinguish between the maternal and zygotic contributions of Bcl-xL to the γ-radiation apoptotic response. Wild-type embryos irradiated before the mid-blastula transition (MBT underwent normal cell division until reaching the MBT, after which they underwent massive, catastrophic apoptosis. Over-expression of Bcl-xL derived from XR11 females, but not males, provided partial protection from apoptosis. Maternal expression of XR11 was also sufficient to abrogate apoptosis triggered by post-MBT γ-radiation. Tolerance to post-MBT γ-radiation from zygotically-derived XR11 was acquired gradually after the MBT in spite of abundant XR11 protein synthesis. Conclusion Our data suggest that Bcl-xL is an effective counterbalance to proapoptotic factors during embryonic development but has no apparent effect on the thyroid hormone-induced apoptosis that occurs during metamorphosis. Furthermore, post-MBT apoptosis

  11. Increased expression of Bcl-2 during mucous cell metaplasia induced by endotoxin and ozone

    Energy Technology Data Exchange (ETDEWEB)

    Tesfaigzi, J.; Ray, L.M.; Hotchkiss, J.A. [Michigan State Univ., East Lansing, MI (United States)] [and others

    1995-12-01

    Apoptosis or programmed cell death is accompanied by characteristic morphological changes that distinguish apoptosis from other forms of cell death. These changes include DNA fragmentation, chromatin condensation, cell shrinkage, cell surface pseudopodia, and finally the cellular collapse into membrane-enclosed apoptotic bodies which are rapidly engulfed by macrophages or neighboring cells. Although the morphological features of apoptotic cells are well studied, the biochemical events that control apoptosis are not understood. Programmed cell death is triggered by a variety of pathways that are initiated by different stimuli including noxious agents, DNA damage, the activation of TNF receptors, or the withdrawl of growth factors. The central process of programmed cell death involves a cascade of biochemical events that begins with the initiation of a family of cysteine proteases, including the interleukin-1-{Beta}-converting enzyme, CPP-32, and Apopain. The ratio of Bax, a death-inducer gene, to Bcl-2, an apoptosis suppressor gene, determines whether or not the main apoptotic pathyway is blocked. Apoptosis is suppressed if the ratio of Bcl-2/Bax is > 1, and cells undergo apoptosis if the ratio is < 1. The overexpression of Bcl-2 has been shown to block the apoptotic program triggered by a variety of agents. Therefore, Bcl-2 must be involved in blocking the central pathway of the cell death program. In conclusion, this study showed that high levels of Bcl-2 were detected in some mucous cells at specific time points during mucous cell metaplasia, and this expression was reduced at later time points or was absent after remodeling of this epithelium.

  12. Bcl-XL, but not Bcl-2, can protect human B-lymphoma cell lines from parthenolide-induced apoptosis

    OpenAIRE

    Yeo, Alan T.; Porco, John A.; Gilmore, Thomas D.

    2011-01-01

    In this report, we investigated the effects of the natural product parthenolide on human B-lymphoma cell lines. We show that parthenolide inhibited NF-κB transcription factor c-Rel (REL). In addition, the sensitivity of several human B-lymphoma cell lines to parthenolide-induced apoptosis inversely correlated with their levels of anti-apoptosis protein Bcl-XL. Furthermore, ectopic expression of Bcl-XL (but not Bcl-2) in two B-lymphoma cell lines decreased their sensitivity to parthenolide-ind...

  13. BCL-2, Ca, and Apoptosis in Breast Cancer

    National Research Council Canada - National Science Library

    Machen, Terry

    1998-01-01

    The central hypothesis of this project is that bcl-2 controls PCD and oncogenesis by altering Ca permeability by the ER/nuclear membranes, mitochondria and/or plasma membrane of mammary epithelial cells...

  14. Bcl-2 apoptosis proteins, mitochondrial membrane curvature, and cancer

    Science.gov (United States)

    Hwee Lai, Ghee; Schmidt, Nathan; Sanders, Lori; Mishra, Abhijit; Wong, Gerard; Ivashyna, Olena; Christenson, Eric; Schlesinger, Paul; Akabori, Kiyotaka; Santangelo, Christian

    2012-02-01

    Critical interactions between Bcl-2 family proteins permeabilize the outer mitochondrial membrane, a common decision point early in the intrinsic apoptotic pathway that irreversibly commits the cell to death. However, a unified picture integrating the essential non-passive role of lipid membranes with the contested dynamics of Bcl-2 regulation remains unresolved. Correlating results between synchrotron x-ray diffraction and microscopy in cell-free assays, we report activation of pro-apoptotic Bax induces strong pure negative Gaussian membrane curvature topologically necessary for pore formation and membrane remodeling events. Strikingly, Bcl-xL suppresses not only Bax-induced pore formation, but also membrane remodeling by disparate systems including cell penetrating, antimicrobial or viral fusion peptides, and bacterial toxin, none of which have BH3 allosteric domains to mediate direct binding. We propose a parallel mode of Bcl-2 pore regulation in which Bax and Bcl-xL induce antagonistic and mutually interacting Gaussian membrane curvatures. The universal nature of curvature-mediated interactions allows synergy with direct binding mechanisms, and potentially accounts for the Bcl-2 family modulation of mitochondrial fission/fusion dynamics.

  15. IL-6-induced Bcl6 variant 2 supports IL-6-dependent myeloma cell proliferation and survival through STAT3

    International Nuclear Information System (INIS)

    Tsuyama, Naohiro; Danjoh, Inaho; Otsuyama, Ken-ichiro; Obata, Masanori; Tahara, Hidetoshi; Ohta, Tsutomu; Ishikawa, Hideaki

    2005-01-01

    IL-6 is a growth and survival factor for myeloma cells, although the mechanism by which it induces myeloma cell proliferation through gene expression is largely unknown. Microarray analysis showed that some B-cell lymphoma-associated oncogenes such as Bcl6, which is absent in normal plasma cells, were upregulated by IL-6 in IL-6-dependent myeloma cell lines. We found that Bcl6 variant 2 was upregulated by STAT3. ChIP assay and EMSA showed that STAT3 bound to the upstream region of variant 2 DNA. Expression of p53, a direct target gene of Bcl6, was downregulated in the IL-6-stimulated cells, and this process was impaired by an HDAC inhibitor. Bcl6 was knocked down by introducing small hairpin RNA, resulting in decreased proliferation and increased sensitivity to a DNA damaging agent. Thus, STAT3-inducible Bcl6 variant 2 appears to generate an important IL-6 signal that supports proliferation and survival of IL-6-dependent myeloma cells

  16. Lack of Bcl-2 expression in follicular lymphoma may be caused by mutations in the BCL2 gene or by absence of the t(14;18) translocation

    NARCIS (Netherlands)

    Schraders, M; de Jong, D; Kluin, P; Groenen, PC; van Krieken, H

    Follicular lymphoma (FL), except grade 3B, is characterized by the chromosomal translocation t(14;18)(q32;q21), which results in over-expression of the Bcl-2 protein. Ten per-cent of all FLs, however, do not show Bcl-2 protein expression with standard immunohistochemistry using a monoclonal Bcl-2

  17. Calcium signals inhibition sensitizes ovarian carcinoma cells to anti-Bcl-xL strategies through Mcl-1 down-regulation.

    Science.gov (United States)

    Bonnefond, Marie-Laure; Lambert, Bernard; Giffard, Florence; Abeilard, Edwige; Brotin, Emilie; Louis, Marie-Hélène; Gueye, Mor Sény; Gauduchon, Pascal; Poulain, Laurent; N'Diaye, Monique

    2015-04-01

    Ovarian carcinoma is the leading cause of death from gynecologic cancer in the developed world and is characterized by acquired chemoresistance leading to an overall 5-year survival rate of about 30 %. We previously showed that Bcl-xL and Mcl-1 cooperatively protect platinum-resistant ovarian cancer cells from apoptosis. Despite BH3-mimetics represent promising drugs to target Bcl-xL, anti-Mcl-1 strategies are still in pre-clinical studies and required new investigations. Calcium is a universal second messenger and dysregulation of calcium signal is often observed during carcinogenesis. As change in cytosolic free calcium concentration [Ca(2+)]i is known to control the fate of the cell by regulating Bcl-2 family members, we wonder if calcium signal could impact on Mcl-1 expression and if its pharmacological inhibition could be useful to sensitize ovarian carcinoma cells to anti-Bcl-xL strategies. We therefore studied the effect of different calcium signals inhibitors in ovarian carcinoma cell lines SKOV3 and IGROV1-R10 and analysed their effects on proliferation and Mcl-1 expression. We also exposed these cells to these inhibitors in combination with anti-Bcl-xL strategies (siRNA or BH3-mimetic: ABT-737). We found that calcium signaling regulates Mcl-1 through translational events and a calmodulin-mediated pathway. BAPTA-AM and calmodulin inhibitor combination with ABT-737 leads to apoptosis, a process that is reversed by Mcl-1 enforced expression. As Mcl-1 represents a crucial hurdle to the success of chemotherapy, these results could open to new area of investigation using calcium modulators to directly or indirectly target Mcl-1 and thus efficiently sensitize ovarian carcinoma cells to anti-Bcl-xL strategies.

  18. The tissue dependent interactions between p53 and Bcl-2 in vivo.

    Science.gov (United States)

    Li, Xin; Miao, Xiao; Wang, Hongshen; Xu, Zhixiang; Li, Bin

    2015-11-03

    To further investigate the role of p53 in apoptosis in vivo and the interaction between p53 and Bcl-2 in the regulation of cellular apoptosis in vivo, we depleted p53 in Bcl-2-null mice. We found that the interaction between p53 and Bcl-2 are tissue dependent. Specifically, loss of p53 in Bcl-2-/- mice inhibits apoptotic induction in spleen and subsequently inhibits the Bcl-2-null-induced spleen atrophy. Furthermore, p53 deficiency overcomes loss of melanocyte stem cell (MSC)-induced apoptosis and subsequently prevents hair graying in Bcl-2- null mice. In addition, p53 deletion partly inhibits apoptosis in hair follicle keratinocytes, leading to the alleviation of hair growth delay in Bcl-2-null mice. However, p53 absence in Bcl-2-null mice cannot restore other defects in Bcl-2-null mice, including retardation of growth, short ears and polycystic kidney disease.

  19. The Role of Bcl-2 Family Proteins in Therapy Responses of Malignant Astrocytic Gliomas: Bcl2L12 and Beyond

    Directory of Open Access Journals (Sweden)

    Fotini M. Kouri

    2012-01-01

    Full Text Available Glioblastoma (GBM is a highly aggressive and lethal brain cancer with a median survival of less than two years after diagnosis. Hallmarks of GBM tumors include soaring proliferative indices, high levels of angiogenesis, diffuse invasion into normal brain parenchyma, resistance toward therapy-induced apoptosis, and pseudopallisading necrosis. Despite the recent advances in neurosurgery, radiation therapy, and the development of targeted chemotherapeutic regimes, GBM remains one of the deadliest types of cancer. Particularly, the alkylating agent temozolomide (TMZ in combination with radiation therapy prolonged patient survival only marginally, and clinical studies assessing efficacies of targeted therapies, foremost ATP mimetics inhibiting the activity of receptor tyrosine kinases (RTKs, revealed only few initial responders; tumor recurrence is nearly universal, and salvage therapies to combat such progression remain ineffective. Consequently, myriad preclinical and clinical studies began to define the molecular mechanisms underlying therapy resistance of GBM tumors, and pointed to the Bcl-2 protein family, in particular the atypical member Bcl2-Like 12 (Bcl2L12, as important regulators of therapy-induced cell death. This review will discuss the multi-faceted modi operandi of Bcl-2 family proteins, describe their roles in therapy resistance of malignant glioma, and outline current and future drug development efforts to therapeutically target Bcl-2 proteins.

  20. The Tumor Suppressor BCL7B Functions in the Wnt Signaling Pathway.

    Directory of Open Access Journals (Sweden)

    Tomoko Uehara

    2015-01-01

    Full Text Available Human BCL7 gene family consists of BCL7A, BCL7B, and BCL7C. A number of clinical studies have reported that BCL7 family is involved in cancer incidence, progression, and development. Among them, BCL7B, located on chromosome 7q11.23, is one of the deleted genes in patients with Williams-Beuren syndrome. Although several studies have suggested that malignant diseases occurring in patients with Williams-Beuren syndrome are associated with aberrations in BCL7B, little is known regarding the function of this gene at the cellular level. In this study, we focused on bcl-7, which is the only homolog of BCL7 gene family in Caenorhabditis elegans, and analyzed bcl-7 deletion mutants. As a result, we found that bcl-7 is required for the asymmetric differentiation of epithelial seam cells, which have self-renewal properties as stem cells and divide asymmetrically through the WNT pathway. Distal tip cell development, which is regulated by the WNT pathway in Caenorhabditis elegans, was also affected in bcl-7-knockout mutants. Interestingly, bcl-7 mutants exhibited nuclear enlargement, reminiscent of the anaplastic features of malignant cells. Furthermore, in KATOIII human gastric cancer cells, BCL7B knockdown induced nuclear enlargement, promoted the multinuclei phenotype and suppressed cell death. In addition, this study showed that BCL7B negatively regulates the Wnt-signaling pathway and positively regulates the apoptotic pathway. Taken together, our data indicate that BCL7B/BCL-7 has some roles in maintaining the structure of nuclei and is involved in the modulation of multiple pathways, including Wnt and apoptosis. This study may implicate a risk of malignancies with BCL7B-deficiency, such as Williams-Beuren syndrome.

  1. MYC expression in concert with BCL2 and BCL6 expression predicts outcome in Chinese patients with diffuse large B-cell lymphoma, not otherwise specified.

    Directory of Open Access Journals (Sweden)

    Li-Xu Yan

    Full Text Available Recent studies provide convincing evidence that a combined immunohistochemical or fluorescence in situ hybridization (FISH score of MYC, BCL2, BCL6 proteins and MYC translocations predicted outcome in diffuse large B-cell lymphoma (DLBCL patients treated with rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP. However, by far, all these researches are based on Western populations. Therefore, we investigate the prognostic relevance of MYC-, BCL2- and BCL6-rearrangements and protein expression by immunohistochemistry and FISH from 336 de novo DLBCL, NOS treated with CHOP or R-CHOP. Breaks in MYC and BCL6, and fusion in IGH/BCL2 were detected in 9.7%, 20.0%, and 11.1% of the cases, respectively, and were not significantly associated with clinical outcomes. Protein overexpression of MYC (≥40%, BCL2 (≥70% and BCL6 (≥50% was encountered in 51%, 51% and 36% of the tumors, respectively. On the basis of MYC, BCL2 and BCL6 expression, double-hit scores (DHSs and triple-hit score (THS were assigned to all patients with DLBCL. Patients with high MYC/BCL2 DHS, high MYC/BCL6 DHS and high THS had multiple adverse prognostic factors including high LDH level, poor performance status, advanced clinical stage, high International Prognostic Index (IPI score, and non-germinal center B-cell. In univariate analysis, high MYC/BCL2 DHS, high MYC/BCL6 DHS and high THS were associated with inferior OS and PFS in both CHOP and R-CHOP cohorts (P0.05. These data together suggest that the immunohistochemical DHSs and THS defined a large subset of DLBCLs with double-hit biology and was strongly associated with poor outcome in patients treated with R-CHOP or CHOP.

  2. Single-cell transcriptomic reconstruction reveals cell cycle and multi-lineage differentiation defects in Bcl11a-deficient hematopoietic stem cells.

    Science.gov (United States)

    Tsang, Jason C H; Yu, Yong; Burke, Shannon; Buettner, Florian; Wang, Cui; Kolodziejczyk, Aleksandra A; Teichmann, Sarah A; Lu, Liming; Liu, Pentao

    2015-09-21

    Hematopoietic stem cells (HSCs) are a rare cell type with the ability of long-term self-renewal and multipotency to reconstitute all blood lineages. HSCs are typically purified from the bone marrow using cell surface markers. Recent studies have identified significant cellular heterogeneities in the HSC compartment with subsets of HSCs displaying lineage bias. We previously discovered that the transcription factor Bcl11a has critical functions in the lymphoid development of the HSC compartment. In this report, we employ single-cell transcriptomic analysis to dissect the molecular heterogeneities in HSCs. We profile the transcriptomes of 180 highly purified HSCs (Bcl11a (+/+) and Bcl11a (-/-)). Detailed analysis of the RNA-seq data identifies cell cycle activity as the major source of transcriptomic variation in the HSC compartment, which allows reconstruction of HSC cell cycle progression in silico. Single-cell RNA-seq profiling of Bcl11a (-/-) HSCs reveals abnormal proliferative phenotypes. Analysis of lineage gene expression suggests that the Bcl11a (-/-) HSCs are constituted of two distinct myeloerythroid-restricted subpopulations. Remarkably, similar myeloid-restricted cells could also be detected in the wild-type HSC compartment, suggesting selective elimination of lymphoid-competent HSCs after Bcl11a deletion. These defects are experimentally validated in serial transplantation experiments where Bcl11a (-/-) HSCs are myeloerythroid-restricted and defective in self-renewal. Our study demonstrates the power of single-cell transcriptomics in dissecting cellular process and lineage heterogeneities in stem cell compartments, and further reveals the molecular and cellular defects in the Bcl11a-deficient HSC compartment.

  3. Identification and characterization of the Bcl-2- associated ...

    African Journals Online (AJOL)

    Identification and characterization of the Bcl-2- associated athanogene (BAG) protein family in rice. ... Data obtained from real-time PCR of OsBAG genes under heat stress showed that maximum induction in the expression of all the genes occurred after one hour exposure to heat stress, while reduction in the expression ...

  4. Evaluation of BCL-2 and transforming growth factor alpha ...

    African Journals Online (AJOL)

    Evaluation of BCL-2 and transforming growth factor alpha oncoproteins in patients with chronic hepatitis C infection: impact on hepatocellular carcinoma. Mahmoud I Hassan, Amal Abou El Fadle, Gamal M Kenawy, Fayda I Abdel Motaleb, Fatma M AbdelSalam ...

  5. Oxidative Modification of miR-184 Enables It to Target Bcl-xL and Bcl-w.

    Science.gov (United States)

    Wang, Jian-Xun; Gao, Jie; Ding, Su-Ling; Wang, Kun; Jiao, Jian-Qin; Wang, Yin; Sun, Teng; Zhou, Lu-Yu; Long, Bo; Zhang, Xiao-Jie; Li, Qian; Liu, Jin-Ping; Feng, Chang; Liu, Jia; Gong, Ying; Zhou, Zhixia; Li, Pei-Feng

    2015-07-02

    MicroRNAs (miRNAs) are small non-coding RNAs, and they bind to complementary sequences in the three prime untranslated regions (3' UTRs) of target mRNA transcripts, thereby inhibiting mRNA translation or promoting mRNA degradation. Excessive reactive oxygen species (ROS) can cause cell-damaging effects through oxidative modification of macromolecules leading to their inappropriate functions. Such oxidative modification is related to cancers, aging, and neurodegenerative and cardiovascular diseases. Here we report that miRNAs can be oxidatively modified by ROS. We identified that miR-184 upon oxidative modification associates with the 3' UTRs of Bcl-xL and Bcl-w that are not its native targets. The mismatch of oxidized miR-184 with Bcl-xL and Bcl-w is involved in the initiation of apoptosis in the study with rat heart cell line H9c2 and mouse models. Our results reveal a model of ROS in regulating cellular events by oxidatively modifying miRNA. Copyright © 2015 Elsevier Inc. All rights reserved.

  6. Bcl-xL regulates CD1d-mediated antigen presentation to NKT cells by altering CD1d trafficking through the endocytic pathway.

    Science.gov (United States)

    Subrahmanyam, Priyanka B; Carey, Gregory B; Webb, Tonya J

    2014-09-01

    NKT cells are a unique subset of T cells that recognize glycolipid Ags presented in the context of CD1d molecules. NKT cells mount strong antitumor responses and are a major focus in developing effective cancer immunotherapy. It is known that CD1d molecules are constantly internalized from the cell surface, recycled through the endocytic compartments, and re-expressed on the cell surface. However, little is known about the regulation of CD1d-mediated Ag processing and presentation in B cell lymphoma. Prosurvival factors of the Bcl-2 family, such as Bcl-xL, are often upregulated in B cell lymphomas and are intimately linked to sphingolipid metabolism, as well as the endocytic compartments. We hypothesized that Bcl-xL can regulate CD1d-mediated Ag presentation to NKT cells. We found that overexpression or induction of Bcl-xL led to increased Ag presentation to NKT cells. Conversely, the inhibition or knockdown of Bcl-xL led to decreased NKT cell activation. Furthermore, knockdown of Bcl-xL resulted in the loss of CD1d trafficking to lysosome-associated membrane protein 1(+) compartments. Rab7, a late endosomal protein, was upregulated and CD1d molecules accumulated in the Rab7(+) late endosomal compartment. These results demonstrate that Bcl-xL regulates CD1d-mediated Ag processing and presentation to NKT cells by altering the late endosomal compartment and changing the intracellular localization of CD1d. Copyright © 2014 by The American Association of Immunologists, Inc.

  7. Influence of BCL2-938 C>A promoter polymorphism and BCL2 gene expression on the progression of breast cancer.

    Science.gov (United States)

    Bhushann Meka, Phanni; Jarjapu, Sarika; Vishwakarma, Sandeep Kumar; Nanchari, Santhoshi Rani; Cingeetham, Anuradha; Annamaneni, Sandhya; Mukta, Srinivasulu; Triveni, B; Satti, Vishnupriya

    2016-05-01

    BCL2 (B-cell leukemia/lymphoma 2) gene functions as antiapoptotic regulatory element and known to be associated with tumorigenesis. The SNP-938 (C>A) (rs2279115), located in the inhibitory P2 promoter of the BCL2 gene, influences differential binding affinities of transcriptional factors thereby affecting BCL2 expression. The present study is an attempt to evaluate the association between BCL2(-938C>A) polymorphism and clinical characteristics of breast cancer patients as well as to analyze BCL2 expression and Ki67 proliferation index with respect to the genotypes. One hundred ten primary breast cancer tumor tissues were genotyped for -938 C>A polymorphism through PCR-RFLP method as well as evaluated for BCL2 expression and ki67 proliferation index by immunohistochemistry. Evaluation of apoptosis level was performed by flowcytometry. The results revealed that AA genotype was associated with an increased risk (AA Vs AC + CC) by 2.86-fold (p = 0.07) for breast cancer development which reflected in elevated A allele frequency also. AA genotype was found to be predominant among BCL2 positive tumors as compared to BCL2 negative tumors. Further, AA genotype was found to be associated with advanced stage tumors, node positive status, and high Ki67 proliferation index compared to CA and CC genotypes indicating that elevated expression of BCL2 gene in the presence of A allele might be associated with decreased apoptosis and enhanced proliferation rate. AA genotype of BCL2-938C>A polymorphism might influence BCL2 gene expression there by associated with elevated risk for breast cancer progression. Probably, failure of apoptosis due to enhanced expression and antiapoptotic protein BCL2 might promote malignant growth.

  8. A sesquiterpenelactone from Inula britannica induces anti-tumor effects dependent on Bcl-2 phosphorylation.

    Science.gov (United States)

    Rafi, Mohamed M; Bai, Nai-Sheng; Chi-Tang-Ho; Rosen, Robert T; White, Eileen; Perez, Denise; Dipaola, Robert S

    2005-01-01

    The over-expression of the anti-apoptotic protein Bcl-2 in cancer is associated with resistance to chemotherapeutic drugs. The phosphorylation of Bcl-2 is one mechanism by which anti-microtubule agents, such as paclitaxel or docetaxel, may inactivate Bcl-2. Although initially active in clinical studies, current anti-microtubule agents are only temporarily effective and the discovery of new agents is warranted. We isolated and identified two known sesquiterpenelactones, O, O-diacetylbritannilactone (OODABL) and O-acetylbritaanilactone (OABL) from the flowers of the medicinal plant Inula britannica and studied their mechanism of anti-tumor effects. To determine the biological significance of Bcl-2 phosphorylation, we used a baby rat kidney (BRK-p53) cell line that was transformed with EIA and a temperature-sensitive mutant p53. The BRK-p53 cell line was transfected with either a vector with wild type Bcl-2 or a vector in which Bcl-2 had mutations in the paclitaxel phosphorylation sites (pcDNA3.1 V5/His Bcl-2 S70, 87A). OODABL and OABL induced phosphorylation of Bcl-2 in breast, ovary and prostate cancer cell lines and induced G2/M cell cycle arrest. Using the BRK cells with mutant Bcl-2 (BRK-Bcl-2-mt) and control (BRK-Bcl-2-wt), we found that OODABL induced phosphorylation of Bcl-2 at sites similar to paclitaxel. Phosphorylation of Bcl-2 was important for OODABL-induced cytotoxicity, since the abrogation of phosphorylation in BRK-Bcl-2-mt cells decreased OODABL-induced cytotoxicity. We concluded that OODABL is cytotoxic in multiple tumor cell lines, and the cytotoxicity is dependent, at least in part, on the phosphorylation of Bcl-2.

  9. The effect of nickel as a nickel chromium restoration corrosion product on gingival fibroblast through analysis of BCl-2

    Directory of Open Access Journals (Sweden)

    FX Ady Soesetijo

    2012-12-01

    Full Text Available Background: Restoration of NiCr may undergo corrosion process in artificial saliva. Corrosion product is soluble Ni substances in salivary electrolytes. Ni2+ may freely enter the cells through passive transport DMT-1. Ni2+ in the cell causes initiation of the ROS formation,which subsequently can conduct the redoxs reactions leading to DNA damage. The damage DNA affects the genetic expression, especially bcl-2, and even triggers apoptosis. Purpose: The aim of this study was to reveal the mechanism of Ni toxicity as a corrosion product of NiCr restoration on gingival fibroblasts through expression analysis of Bcl-2. Methods: Cells with a density of 105 planted on each coverslip in 72 wells to the treatment group and 24 wells to the control group (24 hours incubation. In the treatment groups, each well exposed with 20 μL artificial saliva containing Ni concentration results immerse each restoration, whereas the control group was exposed to 20 μL artificial saliva (incubation 1, 3, and 7 days. The data collected were subsequently analyzed using two-ways ANOVA, followed by one-way ANOVA. Comparing between experimental groups after one-way ANOVA was conducted using Fisher’s LSD. Whereas, the calculation and documentation of Bcl-2 expression was performed camera of Olympus Microscope BX-50 Japan. Results: Statistical analysis of two-ways ANOVA showed the presence of interaction between the increasing Ni concentration and exposure duration on the expression of Bcl-2 gingival fibroblasts (p=0.021Bcl-2 expression.Latar belakang: Restorasi NiCr dapat mengalami proses korosi di dalam saliva artificial. Produk korosi yang dihasilkan adalah substansi Ni yang terlarut di dalam elektrolit saliva. Ni2+ bebas dapat memasuki sel (fibroblas gingiva melalui transport pasif DMT-1. Ni2+ di dalam sel

  10. Design, synthesis and pharmacological evaluation of new acyl sulfonamides as potent and selective Bcl-2 inhibitors.

    Science.gov (United States)

    Liu, Xiaohua; Zhang, Yu; Huang, Wenjing; Tan, Wenfu; Zhang, Ao

    2018-01-15

    The antiapoptotic protein Bcl-2, overexpressed in many tumor cells, is an attractive target for potential small molecule anticancer drug discovery. Herein, we report a different structural modification approach on ABT-263 by merging the piperazinyl-phenyl fragment into a bicyclic framework leading to a series of novel analogues, among which tetrahydroisoquinoline 13 was nearly equally potent against Bcl-2 as ABT-263. Further SAR in the P4-interaction pocket affored the difluoroazetidine substituted analogue 55, which retained good Bcl-2 activity with improved Bcl-2/Bcl-xL selectivity. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. [Antiapoptotic gene bcl-2 prevents cellular senescence program reactivation induced by histone deacetylase inhibitor sodium butyrate in E1A and cHa-ras transformed rat fibroblasts].

    Science.gov (United States)

    Gordeev, S A; Bykova, T V; Zubova, S G; Aksenov, N D; Pospelova, T V

    2015-01-01

    We have investigated the role of apoptosis resistance gene bcl-2 in the activation of cellular senescence program induced by histone deacetylase inhibitor (HDACi) sodium butyrate (NaBut) in transformed rat fibroblasts. This study was conducted in a resistant to apoptosis induction cell line of rat embryo fibroblasts transfor- med by oncogenes E1A, cHa-ras and bcl-2 (ERasBcl). The parent cell line transformed with only EJA and cHa-ras (ERas) was used as a control. It has been found that NaBut reduces proliferation rate of ERasBcl cells significantly weaker than of ERas transformed cells, despite the fact that the G1 cell cycle arrest was observed in both cell lines. After NaBut treatment, hypertrophy of the apoptosis resistant transformants ERasBcl also was reduced compared to parent cell line ERas, due to less activation of mTORC1, which is known to control the synthesis of protein and ribosome biogenesis. The degree of mTORC1 activation was as.sessed by its target proteins phosphorylation: the ribosomal S6 protein and 4E-BP1--inhibitor of translation initiation factor eIF4E. Since cell senescence process may be associated with changes in autophagy regulation, we analyzed the dynamics of one of the main autophagosome formation markers--protein LC3. The accumulation of lipid-bound form LC3-II changes significantly in ERasBcl cells after NaBut treatment and has transient nature. The set of analyzed cellular senescence markers suggests that a high level of apoptosis resistance gene bcl-2 expression prevents the realization of tumor-suppressor senescence program induced by HDACi sodium butyrate treatment.

  12. P53 and bcl-2 assessment in serous ovarian carcinoma.

    Science.gov (United States)

    Palmer, J E; Sant Cassia, L J; Irwin, C J; Morris, A G; Rollason, T P

    2008-01-01

    The study objective was to determine the prognostic value of assessment of staining of p53 and bcl-2 in a well-selected group of serous ovarian carcinomas. Immunohistochemical detection was used to identify both p53 and bcl-2 positive tumors. One hundred thirty-two tumors were analyzed for positivity of staining, grade of staining intensity, and for p53 alone, percent expression rates. These were analyzed alongside traditional clinicopathologic parameters for their ability to predict overall survival (OS), disease-free survival (DFS), and response to chemotherapy (CR). Univariate COX analysis revealed percent p53 expression (P = 0.012) and p53 grade (P = 0.01) to be significant predictors of DFS. Neither the p53 nor bcl-2 measurement parameters were found significant for OS or prediction of CR. On multivariate analysis, incorporating clinicopathologic parameters, p53 parameters did not retain independent significance for any outcome measure. As in primary reported studies, bcl-2 was not found to be of clear independent prognostic value in this group of ovarian tumors. If mutation of p53 and its consequent overexpression is an early event in ovarian tumorigenesis, then p53 assessment may prove useful prognostically in the assessment of either low-grade ovarian carcinomas, as a possible indicator for progression, or in early-stage ovarian tumors, as a marker of tumor aggression or likelihood of recurrence. p53 analysis of a larger group of stage I ovarian tumors would be desirable to further explain the potential association with DFS.

  13. BCL-2 as a Therapeutic Target in Human Tubulointerstitial Inflammation

    Science.gov (United States)

    Ko, Kichul; Wang, Jianing; Perper, Stuart; Jiang, Yulei; Yanez, Denisse; Kaverina, Natalya; Ai, Junting; Liarski, Vladimir M.; Chang, Anthony; Peng, Yahui; Lan, Li; Westmoreland, Susan; Olson, Lisa; Giger, Maryellen L.; Wang, Li Chun; Clark, Marcus R.

    2016-01-01

    Objective In lupus nephritis (LuN), tubulointerstitial inflammation (TII) is associated with in situ adaptive immune cell networks that amplify local tissue damage. As patients with severe TII often fail conventional therapy and develop renal failure, understanding these in situ mechanisms might reveal new therapeutic targets. We hypothesized that in TII, dysregulated apoptotic regulators maintain local adaptive immunity and drive inflammation. Methods We developed novel computational approaches that, when applied to multicolor confocal images, quantified apoptotic regulator protein expression in selected lymphocyte subsets. This approach was validated using laser capture microdissection (LCM) coupled to qPCR. Furthermore, we explored the consequences of dysregulated apoptotic mediator expression in a murine model of LuN. Results Analyses of renal biopsies from LuN and mixed cellular allograft rejection patients revealed that BCL-2 was frequently expressed in infiltrating lymphocytes while expression of MCL-1 was low. In contrast, the reciprocal pattern of expression was observed in tonsil germinal centers. These results were consistent with RNA expression data obtained using LCM and qPCR. BCL-2 was also highly expressed in tubulointerstitial infiltrates of NZB/W F1 mice. Furthermore, treatment of NZB/W F1 mice with ABT-199, a selective oral inhibitor of BCL-2, prolonged survival and prevented proteinuria and development of TII in a prevention model. Interestingly, glomerular immune complexes were partially ameliorated by ABT-199 and serum anti-dsDNA antibody titers were unaffected. Conclusion These data demonstrate BCL-2 as an attractive therapeutic target in LuN manifesting TII. PMID:27159593

  14. NF-κB activation fails to protect cells to TNFα-induced apoptosis in the absence of Bcl-xL, but not Mcl-1, Bcl-2 or Bcl-w.

    Science.gov (United States)

    Casanelles, Elisenda; Gozzelino, Raffaella; Marqués-Fernández, Fernando; Iglesias-Guimarais, Victoria; Garcia-Belinchón, Mercè; Sánchez-Osuna, María; Solé, Carme; Moubarak, Rana S; Comella, Joan X; Yuste, Victor J

    2013-05-01

    TNFα can promote either cell survival or cell death. The activation of NF-κB plays a central role in cell survival while its inhibition makes TNFα-triggered cytotoxicity possible. Here, we report that the overexpression of a non-degradable mutant of the inhibitor of NF-κB (super-repressor (SR)-IκBα) sensitizes HeLa cells towards TNFα-induced apoptosis, involving caspases activation and cytocrome C release from the mitochondria. Interestingly, we describe that the specific knockdown of Bcl-xL, but not that of Bcl-2, Bcl-w or Mcl-1, renders cells sensitive to TNFα-induced apoptosis. This cytotoxic effect occurs without altering the activation of NF-κB. Then, the activation of the NF-κB pathway is not sufficient to protect Bcl-xL-downregulated cells from TNFα-induced cell death, meaning that TNFα is not able to promote cell survival in the absence of Bcl-xL. In addition, Bcl-xL silencing does not potentiate the cytotoxicity afforded by the cytokine in SR-IκBα-overexpressing cells. This indicates that TNFα-induced apoptosis in SR-IκBα-overexpressing cells relies on the protein levels of Bcl-xL. We have corroborated these findings using RD and DU-145 cells, which also become sensitive to TNFα-induced apoptosis after Bcl-xL knockdown despite that NF-κB remains activated. Altogether, our results point out that the impairment of the anti-apoptotic function of Bcl-xL should make cells sensitive towards external insults circumventing the TNFα-triggered NF-κB-mediated cytoprotective effect. Hence, the specific inhibition of Bcl-xL could be envisaged as a promising alternative strategy against NF-κB-dependent highly chemoresistant proliferative malignancies. Copyright © 2013 Elsevier B.V. All rights reserved.

  15. Mutual regulation of Bcl-2 proteins independent of the BH3 domain as shown by the BH3-lacking protein Bcl-x(AK.

    Directory of Open Access Journals (Sweden)

    Michael Plötz

    Full Text Available The BH3 domain of Bcl-2 proteins was regarded as indispensable for apoptosis induction and for mutual regulation of family members. We recently described Bcl-x(AK, a proapoptotic splice product of the bcl-x gene, which lacks BH3 but encloses BH2, BH4 and a transmembrane domain. It remained however unclear, how Bcl-x(AK may trigger apoptosis.For efficient overexpression, Bcl-x(AK was subcloned in an adenoviral vector under Tet-OFF control. The construct resulted in significant apoptosis induction in melanoma and nonmelanoma cell lines with up to 50% apoptotic cells as well as decreased cell proliferation and survival. Disruption of mitochondrial membrane potential, and cytochrome c release clearly indicated activation of the mitochondrial apoptosis pathways. Both Bax and Bak were activated as shown by clustering and conformation analysis. Mitochondrial translocation of Bcl-x(AK appeared as an essential and initial step. Bcl-x(AK was critically dependent on either Bax or Bak, and apoptosis was abrogated in Bax/Bak double knockout conditions as well by overexpression of Bcl-2 or Bcl-x(L. A direct interaction with Bcl-2, Bax, Bad, Noxa or Puma was however not seen by immunoprecipitation. Thus besides BH3-mediated interactions, there exists an additional way for mutual regulation of Bcl-2 proteins, which is independent of the BH3. This pathway appears to play a supplementary role also for other proapoptotic family members, and its unraveling may help to overcome therapy resistance in cancer.

  16. Bcl-2 silencing attenuates hypoxia-induced apoptosis resistance in pulmonary microvascular endothelial cells.

    Science.gov (United States)

    Cao, Yongmei; Jiang, Zhen; Zeng, Zhen; Liu, Yujing; Gu, Yuchun; Ji, Yingying; Zhao, Yupeng; Li, Yingchuan

    2016-01-01

    Pulmonary arterial hypertension (PAH) is a life-threatening disorder that ultimately causes heart failure. While the underlying causes of this condition are not well understood, previous studies suggest that the anti-apoptotic nature of pulmonary microvascular endothelial cells (PMVECs) in hypoxic environments contributes to PAH pathogenesis. In this study, we focus on the contribution of Bcl-2 and hypoxia response element (HRE) to apoptosis-resistant endothelial cells and investigate the mechanism. PMVECs obtained from either normal rats or apoptosis-resistant PMVECs obtained from PAH rats were transduced with recombinant lentiviral vectors carrying either Bcl-2-shRNA or HRE combined Bcl-2-shRNA, and then cultured these cells for 24 h under hypoxic (5% O2) or normoxic (21% O2) conditions. In normal PMVECs, Bcl-2-shRNA or HRE combined with Bcl-2-shRNA transduction successfully decreased Bcl-2 expression, while increasing apoptosis as well as caspase-3 and P53 expression in a normoxic environment. In a hypoxic environment, the effects of Bcl-2-shRNA treatment on cell apoptosis, and on Bcl-2, caspase-3, P53 expression were significantly suppressed. Conversely, HRE activation combined with Bcl-2-shRNA transduction markedly enhanced cell apoptosis and upregulated caspase-3 and P53 expression, while decreasing Bcl-2 expression. Furthermore, in apoptosis-resistant PMVECs, HRE-mediated Bcl-2 silencing effectively enhanced cell apoptosis and caspase-3 activity. The apoptosis rate was significantly depressed when Lv-HRE-Bcl-2-shRNA was combined with Lv-P53-shRNA or Lv-caspase3-shRNA transduction in a hypoxic environment. These results suggest that HRE-mediated Bcl-2 inhibition can effectively attenuate hypoxia-induced apoptosis resistance in PMVECs by downregulating Bcl-2 expression and upregulating caspase-3 and P53 expression. This study therefore reveals critical insight into potential therapeutic targets for treating PAH.

  17. Unintended target effect of anti-BCL-2 DNAi

    Directory of Open Access Journals (Sweden)

    Ebrahim AS

    2017-09-01

    Full Text Available Abdul Shukkur Ebrahim,1 Mustapha Kandouz,2 Nada Emara,1 Amara B Sugalski,3 Leonard Lipovich,3 Ayad M Al-Katib1 1Lymphoma Research Laboratory, 2Department of Pathology, School of Medicine, 3Center for Molecular Medicine and Genetics, Wayne State University, Detroit, MI, USA Introduction: Previous research suggested that a novel compound PNT2258 inhibits B-cell lymphoma 2 (BCL-2 transcription by DNA interference (DNAi and demonstrated its activity in preclinical xenograft models and in a pilot Phase II clinical trial in non-Hodgkin’s lymphoma (NHL. While the drug downregulates BCL-2 at the promoter, mRNA, and protein levels, there is a significant homology (13–16 bases between PNT100 and a number of promoters of genes involved in cell cycle regulation and survival. In this study, we identify cyclin-dependent kinase-4 (CDK4 as an unintended target gene of PNT2258 and examine its relevance to NHL.Methods: We performed a Basic Local Alignment Search Tool (BLAST homology search using PNT100 DNAi sequences. Also, we conducted CDK4 promoter assay in K562 cells and studied the protein expression of CDK4 in Wayne State University (WSU-follicular small cleaved cell lymphoma (FSCCL, WSU-diffuse large cell lymphoma, and WSU-Waldenström’s macroglobulinemia (WM lymphoma cells.Results: BLAST homology search showed that PNT100 completely binds to BCL-2 gene as expected. However, there was 100% homology in a stretch of 14 bases (8–21 between PNT100 and CDK4. PNT2258 strongly inhibited CDK4 promoter activity in K562 cells. Moreover, CDK4 protein expression was significantly downregulated by PNT2258 in WSU-FSCCL and WSU-WM cell lines. Discussion: DNAi may work not only through knocking down the intended gene but also by knocking down other genes. PNT2258 affects CDK4 expression and promoter activity. Results of the present study suggest a broader mechanism of action for DNAi targeting both intended (BCL-2 and unintended (CDK4 genes. Keywords: non

  18. Poliovirus modulates Bcl-xl expression in the human U937 promonocytic cell line.

    Science.gov (United States)

    Calandria, C; López-Guerrero, J A

    2002-12-01

    Poliovirus induces bcl-2-independent apoptosis in the human U937 promonocytic cell line [28]. Here we describe that this cell death, induced after viral infection, correlates with the modulation of the protooncoprotein Bcl-xl. Furthermore, poliovirus infection decreases the detected Bcl-xl in a U937 clone that overexpresses this protein (U937bcl-xl). Although in U937bcl-xl cells, Bcl-xl was not as highly regulated as in parental U937 cells, correlation between Bcl-xl modulation and the cleavage of poly(ADP-ribose)polymerase could be observed. Nevertheless, the induction of shutoff after infection of transfected control U937neo or U937bcl-xl clones was not significantly altered. Finally, production of new viral particles was slightly restricted in Bcl-xl-overexpressing U937 cells. Taken together, these results suggest that Bcl-xl is modulated during the induction of apoptosis in the promonocytic cell line U937 after poliovirus infection, although modulation of this protooncogene was not sufficient to modify the course of infection.

  19. Bcl-2 prevents loss of mitochondria in CCCP-induced apoptosis

    International Nuclear Information System (INIS)

    Graaf, Aniek O. de; Heuvel, Lambert P. van den; Dijkman, Henry B.P.M.; Abreu, Ronney A. de; Birkenkamp, Kim U.; Witte, Theo de; Reijden, Bert A. van der; Smeitink, Jan A.M.; Jansen, Joop H.

    2004-01-01

    Bcl-2 family proteins regulate apoptosis at the level of mitochondria. To examine the mechanism of Bcl-2 function, we investigated the effects of the protonophore carbonyl cyanide m-chlorophenyl hydrazone (CCCP) on two hematopoietic cell lines and Bcl-2 overexpressing transfectants. CCCP directly interferes with mitochondrial function and induces apoptosis. We show that Bcl-2 inhibits apoptosis and that the antiapoptotic effect of Bcl-2 takes place upstream of caspase activation and nuclear changes associated with apoptosis, since these were markedly inhibited in cells overexpressing Bcl-2. Bcl-2 does not prevent the decrease in mitochondrial membrane potential nor the alterations in cellular ATP content induced by CCCP in FL5.12 and Jurkat cells. A higher number of mitochondria was observed in untreated Bcl-2 transfected cells compared to parental cells, as shown by electron microscopy. Exposure to CCCP induced a dramatic decrease in the number of mitochondria and severely disrupted mitochondrial ultrastructure, with apparent swelling and loss of cristae in parental cells. Bcl-2 clearly diminished the disruption of mitochondrial structure and preserved a higher number of mitochondria. These data suggest that CCCP induces apoptosis by structural disruption of mitochondria and that Bcl-2 prevents apoptosis and mitochondrial degeneration by preserving mitochondrial integrity

  20. Akt regulates drug-induced cell death through Bcl-w downregulation.

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    Michela Garofalo

    Full Text Available Akt is a serine threonine kinase with a major role in transducing survival signals and regulating proteins involved in apoptosis. To find new interactors of Akt involved in cell survival, we performed a two-hybrid screening in yeast using human full-length Akt c-DNA as bait and a murine c-DNA library as prey. Among the 80 clones obtained, two were identified as Bcl-w. Bcl-w is a member of the Bcl-2 family that is essential for the regulation of cellular survival, and that is up-regulated in different human tumors, such as gastric and colorectal carcinomas. Direct interaction of Bcl-w with Akt was confirmed by immunoprecipitation assays. Subsequently, we addressed the function of this interaction: by interfering with the activity or amount of Akt, we have demonstrated that Akt modulates the amount of Bcl-w protein. We have found that inhibition of Akt activity may promote apoptosis through the downregulation of Bcl-w protein and the consequential reduction in interaction of Bcl-w with pro-apoptotic members of the Bcl-2 family. Our data provide evidence that Bcl-w is a new member of the Akt pathway and that Akt may induce anti-apoptotic signals at least in part through the regulation of the amount and activity of Bcl-w.

  1. Akt regulates drug-induced cell death through Bcl-w downregulation.

    Science.gov (United States)

    Garofalo, Michela; Quintavalle, Cristina; Zanca, Ciro; De Rienzo, Assunta; Romano, Giulia; Acunzo, Mario; Puca, Loredana; Incoronato, Mariarosaria; Croce, Carlo M; Condorelli, Gerolama

    2008-01-01

    Akt is a serine threonine kinase with a major role in transducing survival signals and regulating proteins involved in apoptosis. To find new interactors of Akt involved in cell survival, we performed a two-hybrid screening in yeast using human full-length Akt c-DNA as bait and a murine c-DNA library as prey. Among the 80 clones obtained, two were identified as Bcl-w. Bcl-w is a member of the Bcl-2 family that is essential for the regulation of cellular survival, and that is up-regulated in different human tumors, such as gastric and colorectal carcinomas. Direct interaction of Bcl-w with Akt was confirmed by immunoprecipitation assays. Subsequently, we addressed the function of this interaction: by interfering with the activity or amount of Akt, we have demonstrated that Akt modulates the amount of Bcl-w protein. We have found that inhibition of Akt activity may promote apoptosis through the downregulation of Bcl-w protein and the consequential reduction in interaction of Bcl-w with pro-apoptotic members of the Bcl-2 family. Our data provide evidence that Bcl-w is a new member of the Akt pathway and that Akt may induce anti-apoptotic signals at least in part through the regulation of the amount and activity of Bcl-w.

  2. In silico Sequence Analysis, Structure Prediction and Function Annotation of Human Bcl-X Beta Protein

    Directory of Open Access Journals (Sweden)

    Anjali Singh

    2014-03-01

    Full Text Available Bcl-X proteins are the one of the best categorized member of the Bcl-2 protein families which acts as primary regulators of apoptosis in mammalian cells. The Bcl-X proteins are potential anti-cancer drug targets. In this study, the tertiary structure of the beta isoform of the apoptosis regulator Bcl-X in humans (h-Bcl-Xβ has been predicted by fold-recognition (threading approach. In silico assessment of the h-Bcl-Xβ protein revealed the characteristic structural features of anti-apoptotic Bcl-2 protein family in h-Bcl-Xβ protein. The predicted model was comprised of BH1-BH4 domains, seven alpha-helices and a C-terminal transmembrane domain for membrane localization and sub-cellular targeting. Quality assessment of the predict model confirmed its reliability as fairly good model. Active sites of h-Bcl-Xβ protein were identified using CASTp server. The future work can be directed towards drug designing for cancer treatment by regulating the activity of h-Bcl-Xβ proteins.

  3. Energetic heavy ions overcome tumor radioresistance caused by overexpression of Bcl-2

    International Nuclear Information System (INIS)

    Hamada, Nobuyuki; Hara, Takamitsu; Omura-Minamisawa, Motoko; Funayama, Tomoo; Sakashita, Tetsuya; Sora, Sakura; Yokota, Yuichiro; Nakano, Takashi

    2008-01-01

    Background and purpose: Overexpression of Bcl-2 is frequent in human cancers and has been associated with radioresistance. Here we investigated the potential impact of heavy ions on Bcl-2 overexpressing tumors. Materials and methods: Bcl-2 cells (Bcl-2 overexpressing HeLa cells) and Neo cells (neomycin resistant gene-expressing HeLa cells) exposed to γ-rays or heavy ions were assessed for the clonogenic survival, apoptosis and cell cycle distribution. Results: Whereas Bcl-2 cells were more resistant to γ-rays (0.2 keV/μm) and helium ions (16.2 keV/μm) than Neo cells, heavy ions (76.3-1610 keV/μm) yielded similar survival regardless of Bcl-2 overexpression. Carbon ions (108 keV/μm) decreased the difference in the apoptotic incidence between Bcl-2 and Neo cells, and prolonged G 2 /M arrest that occurred more extensively in Bcl-2 cells than in Neo cells. Conclusions: High-LET heavy ions overcome tumor radioresistance caused by Bcl-2 overexpression, which may be explained at least in part by the enhanced apoptotic response and prolonged G 2 /M arrest. Thus, heavy-ion therapy may be a promising modality for Bcl-2 overexpressing radioresistant tumors

  4. Micro-Economics of Apoptosis in Cancer: ncRNAs Modulation of BCL-2 Family Members.

    Science.gov (United States)

    Villanova, Lidia; Careccia, Silvia; De Maria, Ruggero; Fiori, Micol E

    2018-03-23

    In the last few years, non-coding RNAs (ncRNAs) have been a hot topic in cancer research. Many ncRNAs were found to regulate the apoptotic process and to play a role in tumor cell resistance to treatment. The apoptotic program is on the frontline as self-defense from cancer onset, and evasion of apoptosis has been classified as one of the hallmarks of cancer responsible for therapy failure. The B-cell lymphoma 2 (BCL-2) family members are key players in the regulation of apoptosis and mediate the activation of the mitochondrial death machinery in response to radiation, chemotherapeutic agents and many targeted therapeutics. The balance between the pro-survival and the pro-apoptotic BCL-2 proteins is strictly controlled by ncRNAs. Here, we highlight the most common mechanisms exerted by microRNAs, long non-coding RNAs and circular RNAs on the main mediators of the intrinsic apoptotic cascade with particular focus on their significance in cancer biology.

  5. Mito-priming as a method to engineer Bcl-2 addiction.

    Science.gov (United States)

    Lopez, Jonathan; Bessou, Margaux; Riley, Joel S; Giampazolias, Evangelos; Todt, Franziska; Rochegüe, Tony; Oberst, Andrew; Green, Douglas R; Edlich, Frank; Ichim, Gabriel; Tait, Stephen W G

    2016-02-02

    Most apoptotic stimuli require mitochondrial outer membrane permeabilization (MOMP) in order to execute cell death. As such, MOMP is subject to tight control by Bcl-2 family proteins. We have developed a powerful new technique to investigate Bcl-2-mediated regulation of MOMP. This method, called mito-priming, uses co-expression of pro- and anti-apoptotic Bcl-2 proteins to engineer Bcl-2 addiction. On addition of Bcl-2 targeting BH3 mimetics, mito-primed cells undergo apoptosis in a rapid and synchronous manner. Using this method we have comprehensively surveyed the efficacy of BH3 mimetic compounds, identifying potent and specific MCL-1 inhibitors. Furthermore, by combining different pro- and anti-apoptotic Bcl-2 pairings together with CRISPR/Cas9-based genome editing, we find that tBID and PUMA can preferentially kill in a BAK-dependent manner. In summary, mito-priming represents a facile and robust means to trigger mitochondrial apoptosis.

  6. Combined Targeting of JAK2 and Bcl-2/Bcl-xL to Cure Mutant JAK2-Driven Malignancies and Overcome Acquired Resistance to JAK2 Inhibitors

    Directory of Open Access Journals (Sweden)

    Michaela Waibel

    2013-11-01

    Full Text Available To design rational therapies for JAK2-driven hematological malignancies, we functionally dissected the key survival pathways downstream of hyperactive JAK2. In tumors driven by mutant JAK2, Stat1, Stat3, Stat5, and the Pi3k and Mek/Erk pathways were constitutively active, and gene expression profiling of TEL-JAK2 T-ALL cells revealed the upregulation of prosurvival Bcl-2 family genes. Combining the Bcl-2/Bcl-xL inhibitor ABT-737 with JAK2 inhibitors mediated prolonged disease regressions and cures in mice bearing primary human and mouse JAK2 mutant tumors. Moreover, combined targeting of JAK2 and Bcl-2/Bcl-xL was able to circumvent and overcome acquired resistance to single-agent JAK2 inhibitor treatment. Thus, inhibiting the oncogenic JAK2 signaling network at two nodal points, at the initiating stage (JAK2 and the effector stage (Bcl-2/Bcl-xL, is highly effective and provides a clearly superior therapeutic benefit than targeting just one node. Therefore, we have defined a potentially curative treatment for hematological malignancies expressing constitutively active JAK2.

  7. Molecular docking studies of bioactive compounds from Annona muricata Linn as potential inhibitors for Bcl-2, Bcl-w and Mcl-1 antiapoptotic proteins.

    Science.gov (United States)

    Mohamad Rosdi, Mohamad Norisham; Mohd Arif, Shahkila; Abu Bakar, Mohamad Hafizi; Razali, Siti Aisyah; Mohamed Zulkifli, Razauden; Ya'akob, Harisun

    2018-01-01

    Annona muricata Linn or usually identified as soursop is a potential anticancer plant that has been widely reported to contain valuable chemopreventive agents known as annonaceous acetogenins. The antiproliferative and anticancer activities of this tropical and subtropical plant have been demonstrated in cell culture and animal studies. A. muricata L. exerts inhibition against numerous types of cancer cells, involving multiple mechanism of actions such as apoptosis, a programmed cell death that are mainly regulated by Bcl-2 family of proteins. Nonetheless, the binding mode and the molecular interactions of the plant's bioactive constituents have not yet been unveiled for most of these mechanisms. In the current study, we aim to elucidate the binding interaction of ten bioactive phytochemicals of A. muricata L. to three Bcl-2 family of antiapoptotic proteins viz. Bcl-2, Bcl-w and Mcl-1 using an in silico molecular docking analysis software, Autodock 4.2. The stability of the complex with highest affinity was evaluated using MD simulation. We compared the docking analysis of these substances with pre-clinical Bcl-2 inhibitor namely obatoclax. The study identified the potential chemopreventive agent among the bioactive compounds. We also characterized the important interacting residues of protein targets which involve in the binding interaction. Results displayed that anonaine, a benzylisoquinoline alkaloid, showed a high affinity towards the Bcl-2, thus indicating that this compound is a potent inhibitor of the Bcl-2 antiapoptotic family of proteins.

  8. Growth- and tumor-promoting effects of deregulated BCL2 in human B-lymphoblastoid cells

    International Nuclear Information System (INIS)

    Nunez, G.; Seto, M.; Seremetis, S.; Ferrero, D.; Grignani, F.; Korsmeyer, S.J.; Dalla-Favera, R.

    1989-01-01

    Human follicular B-cell lymphomas possess a t(14;18) that translocates a putative protooncogene, BCL2, into the immunoglobulin heavy chain locus. The normal BCL2 gene is quiescent in resting B cells, expressed in proliferating, but down-regulated in differentiated B cells. Inappropriately high levels of BCL2-immunoglobulin chimeric RNA are present in t(14;18) lymphomas for their mature B-cell stage. The authors examined the biologic effects of BCL2 deregulation in human B cells by introducing BCL2 into human B-lymphoblastoid cell lines (LCLs) with retroviral gene transfer. Although deregulated BCL2 expression as a single agent was not sufficient to confer tumorigenicity to LCLs, it consistently produced a 3- to 4-fold increment in LCL clonogenicity in soft agar. In addition, BCL2 deregulation complements the transforming effects of the MYC oncogene in LCLs. BCL2 augmented the clonogenicity of LCLs bearing exogenous MYC and increased the frequency and shortened the latency of tumor induction in immunodeficient mice. These results demonstrate a role for BCL2 as a protooncogene that affects B-cell growth and enhances B-cell neoplasia

  9. The BCL6 RD2 Domain Governs Commitment of Activated B Cells to Form Germinal Centers

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    Chuanxin Huang

    2014-09-01

    Full Text Available To understand how the Bcl6 transcriptional repressor functions in the immune system, we disrupted its RD2 repression domain in mice. Bcl6RD2MUT mice exhibit a complete loss of germinal center (GC formation but retain normal extrafollicular responses. Bcl6RD2MUT antigen-engaged B cells migrate to the interfollicular zone and interact with cognate T helper cells. However, these cells fail to complete early GC-commitment differentiation and coalesce as nascent GC aggregates. Bcl6 directly binds and represses trafficking receptors S1pr1 and Gpr183 by recruiting Hdac2 through the RD2 domain. Deregulation of these genes impairs B cell migration and may contribute to GC failure in Bcl6RD2MUT mice. The development of functional GC-TFH cells was partially impaired in Bcl6RD2MUT mice. In contrast to Bcl6−/− mice, Bcl6RD2MUT animals experience no inflammatory disease or macrophage deregulation. These results reveal an essential role for RD2 repression in early GC commitment and striking biochemical specificity in Bcl6 control of humoral and innate immune-cell phenotypes.

  10. Borax-induced apoptosis in HepG2 cells involves p53, Bcl-2, and Bax.

    Science.gov (United States)

    Wei, Y; Yuan, F J; Zhou, W B; Wu, L; Chen, L; Wang, J J; Zhang, Y S

    2016-06-21

    Borax, a boron compound and a salt of boric acid, is known to inhibit the growth of tumor cells. HepG2 cells have been shown to be clearly susceptible to the anti-proliferative effects of borax. However, the specific mechanisms regulating this effect are poorly understood. This study aimed to investigate the pathways underlying the growth inhibition induced by borax in HepG2 cells. The effects of borax on HepG2 cell viability were characterized using MTT. Apoptosis was also verified by annexin V/propidium iodide staining. JC-1 dye and western blotting techniques were used to measure mitochondrial membrane potential and p53, Bax, and Bcl-2 protein expression, respectively. Relevant mRNA levels were measured by qRT-PCR. Borax inhibited the proliferation of HepG2 cells in a time- and dose-dependent manner in vitro. The apoptotic process triggered by borax involved the upregulation of p53 and Bax and the downregulation of Bcl-2, which was confirmed by a change in the mitochondrial membrane potential. These results elucidate a borax-induced apoptotic pathway in HepG2 cells that involves the upregulation of p53 and Bax and the downregulation of Bcl-2.

  11. Molecular interactions of prodiginines with the BH3 domain of anti-apoptotic Bcl-2 family members.

    Directory of Open Access Journals (Sweden)

    Ali Hosseini

    Full Text Available Prodigiosin and obatoclax, members of the prodiginines family, are small molecules with anti-cancer properties that are currently under preclinical and clinical trials. The molecular target(s of these agents, however, is an open question. Combining experimental and computational techniques we find that prodigiosin binds to the BH3 domain in some BCL-2 protein families, which play an important role in the apoptotic programmed cell death. In particular, our results indicate a large affinity of prodigiosin for MCL-1, an anti-apoptotic member of the BCL-2 family. In melanoma cells, we demonstrate that prodigiosin activates the mitochondrial apoptotic pathway by disrupting MCL-1/BAK complexes. Computer simulations with the PELE software allow the description of the induced fit process, obtaining a detailed atomic view of the molecular interactions. These results provide new data to understand the mechanism of action of these molecules, and assist in the development of more specific inhibitors of anti-apoptotic BCL-2 proteins.

  12. Red photon treatment inhibits apoptosis via regulation of bcl-2 proteins and ROS levels, alleviating hypoxic-ischemic brain damage.

    Science.gov (United States)

    Jiang, W; Chen, L; Zhang, X J; Chen, J; Li, X C; Hou, W S; Xiao, N

    2014-05-30

    Therapeutic options for hypoxic-ischemic brain damage (HIBD) are scarce and inefficient. Recently, many studies have demonstrated that red photon plays an important role in anti-inflammatory processes as well as apoptosis, the main trait of HIBD. In this study, we investigated whether red photon can protect from HIBD in SD rats and oxygen-glucose deprivation (OGD) in PC12 cells. Apoptosis, mitochondrial transmembrane potential (MMP), and reactive oxygen species (ROS) rates were assessed in PC12 cells. We found that 6-h irradiation resulted in decreased MMP, ROS and apoptosis rates, although these changes were reversible with prolonged irradiation. Importantly, these effects were sustained for 2-8h upon quenching of the red photon. Similar trends were observed for protein and mRNA expression of bax and bcl-2, with short-term irradiation (6h) inhibiting apoptosis in PC12 Cells. However, long-term (>6h) irradiation caused cell damage. In vivo experiments, bax mRNA and protein levels were reduced after 7days in HIBD model rats treated with red photon, in contrast to bcl-2. Furthermore, we found that bax and bcl-2 were mainly expressed in pyramidal cells of the hippocampus CA1 and CA3. Importantly, Morris Water Maze test results revealed an improvement in learning ability and spatial memory in rats after irradiation. Overall, our data showed that short-term irradiation with red photon in the acute phase inhibits the mitochondrial apoptotic pathway via regulation of bcl-2-related proteins and reduction of ROS levels, thereby decreasing apoptosis in nerve cells and improving the neurological prognosis of HIBD. Copyright © 2014 IBRO. Published by Elsevier Ltd. All rights reserved.

  13. Phospho-Bcl-xL(Ser62) influences spindle assembly and chromosome segregation during mitosis.

    Science.gov (United States)

    Wang, Jianfang; Beauchemin, Myriam; Bertrand, Richard

    2014-01-01

    Functional analysis of a series of phosphorylation mutants reveals that Bcl-xL(Ser62Ala) influences cell entry into anaphase and mitotic exit in taxol-exposed cells compared with cells expressing wild-type Bcl-xL or a series of other phosphorylation mutants, an effect that appears to be independent of its anti-apoptotic activity. During normal mitosis progression, Bcl-xL(Ser62) is strongly phosphorylated by PLK1 and MAPK14/SAPKp38α at the prometaphase, metaphase, and the anaphase boundaries, while it is de-phosphorylated at telophase and cytokinesis. Phospho-Bcl-xL(Ser62) localizes in centrosomes with γ-tubulin and in the mitotic cytosol with some spindle-assembly checkpoint signaling components, including PLK1, BubR1, and Mad2. In taxol- and nocodazole-exposed cells, phospho-Bcl-xL(Ser62) also binds to Cdc20- Mad2-, BubR1-, and Bub3-bound complexes, while Bcl-xL(Ser62Ala) does not. Silencing Bcl-xL expression and expressing the phosphorylation mutant Bcl-xL(Ser62Ala) lead to an increased number of cells harboring mitotic spindle defects including multipolar spindle, chromosome lagging and bridging, aneuploidy with micro-, bi-, or multi-nucleated cells, and cells that fail to resolve undergo mitosis within 6 h. Together, the data indicate that during mitosis, Bcl-xL(Ser62) phosphorylation impacts on spindle assembly and chromosome segregation, influencing chromosome stability. Observations of mitotic cells harboring aneuploidy with micro-, bi-, or multi-nucleated cells, and cells that fail to resolve undergo mitosis within 6 h were also made with cells expressing the phosphorylation mutant Bcl-xL(Ser49Ala) and dual mutant Bcl-xL(Ser49/62Ala).

  14. Amphipathic tail-anchoring peptide and Bcl-2 homology domain-3 (BH3) peptides from Bcl-2 family proteins induce apoptosis through different mechanisms.

    Science.gov (United States)

    Ko, Jae-Kyun; Choi, Kyoung-Han; Peng, Jun; He, Feng; Zhang, Zhi; Weisleder, Noah; Lin, Jialing; Ma, Jianjie

    2011-03-18

    Bcl-2 homology domain-3 (BH3) peptides are potent cancer therapeutic reagents that target regulators of apoptotic cell death in cancer cells. However, their cytotoxic effects are affected by different expression levels of Bcl-2 family proteins. We recently found that the amphipathic tail-anchoring peptide (ATAP) from Bfl-1, a bifunctional Bcl-2 family member, produced strong pro-apoptotic activity by permeabilizing the mitochondrial outer membrane. Here, we test whether the activity of ATAP requires other cellular factors and whether ATAP has an advantage over the BH3 peptides in targeting cancer cells. Confocal microscopic imaging illustrates specific targeting of ATAP to mitochondria, whereas BH3 peptides show diffuse patterns of cytosolic distribution. Although the pro-apoptotic activities of BH3 peptides are largely inhibited by either overexpression of anti-apoptotic Bcl-2 or Bcl-xL or nullification of pro-apoptotic Bax and Bak in cells, the pro-apoptotic function of ATAP is not affected by these cellular factors. Reconstitution of synthetic ATAP into liposomal membranes results in release of fluorescent molecules of the size of cytochrome c from the liposomes, suggesting that the membrane permeabilizing activity of ATAP does not require additional protein factors. Because ATAP can target to the mitochondrial membrane and its pro-apoptotic activity does not depend on the content of Bcl-2 family proteins, it represents a promising candidate for anti-cancer drugs that can potentially overcome the intrinsic apoptosis-resistant nature of cancer cells.

  15. Mapping the BH3 Binding Interface of Bcl-xL, Bcl-2, and Mcl-1 Using Split-Luciferase Reassembly.

    Science.gov (United States)

    Campbell, Sean T; Carlson, Kevin J; Buchholz, Carl J; Helmers, Mark R; Ghosh, Indraneel

    2015-04-28

    The recognition of helical BH3 domains by Bcl-2 homology (BH) receptors plays a central role in apoptosis. The residues that determine specificity or promiscuity in this interactome are difficult to predict from structural and computational data. Using a cell free split-luciferase system, we have generated a 276 pairwise interaction map for 12 alanine mutations at the binding interface for three receptors, Bcl-xL, Bcl-2, and Mcl-1, and interrogated them against BH3 helices derived from Bad, Bak, Bid, Bik, Bim, Bmf, Hrk, and Puma. This panel, in conjunction with previous structural and functional studies, starts to provide a more comprehensive portrait of this interactome, explains promiscuity, and uncovers surprising details; for example, the Bcl-xL R139A mutation disrupts binding to all helices but the Bad-BH3 peptide, and Mcl-1 binding is particularly perturbed by only four mutations of the 12 tested (V220A, N260A, R263A, and F319A), while Bcl-xL and Bcl-2 have a more diverse set of important residues depending on the bound helix.

  16. Crosstalk between Bcl-2 family and Ras family small GTPases: potential cell fate regulation?

    International Nuclear Information System (INIS)

    Kang, Jia; Pervaiz, Shazib

    2013-01-01

    Cell fate regulation is a function of diverse cell signaling pathways that promote cell survival and or inhibit cell death execution. In this regard, the role of the Bcl-2 family in maintaining a tight balance between cell death and cell proliferation has been extensively studied. The conventional dogma links cell fate regulation by the Bcl-2 family to its effect on mitochondrial permeabilization and apoptosis amplification. However, recent evidence provide a novel mechanism for death regulation by the Bcl-2 family via modulating cellular redox metabolism. For example overexpression of Bcl-2 has been shown to contribute to a pro-oxidant intracellular milieu and down-regulation of cellular superoxide levels enhanced death sensitivity of Bcl-2 overexpressing cells. Interestingly, gene knockdown of the small GTPase Rac1 or pharmacological inhibition of its activity also reverted death phenotype in Bcl-2 expressing cells. This appears to be a function of an interaction between Bcl-2 and Rac1. Similar functional associations have been described between the Bcl-2 family and other members of the Ras superfamily. These interactions at the mitochondria provide novel opportunities for strategic therapeutic targeting of drug-resistant cancers.

  17. Bcl-xL regulates mitochondrial energetics by stabilizing the inner membrane potential.

    Science.gov (United States)

    Chen, Ying-Bei; Aon, Miguel A; Hsu, Yi-Te; Soane, Lucian; Teng, Xinchen; McCaffery, J Michael; Cheng, Wen-Chih; Qi, Bing; Li, Hongmei; Alavian, Kambiz N; Dayhoff-Brannigan, Margaret; Zou, Shifa; Pineda, Fernando J; O'Rourke, Brian; Ko, Young H; Pedersen, Peter L; Kaczmarek, Leonard K; Jonas, Elizabeth A; Hardwick, J Marie

    2011-10-17

    Mammalian Bcl-x(L) protein localizes to the outer mitochondrial membrane, where it inhibits apoptosis by binding Bax and inhibiting Bax-induced outer membrane permeabilization. Contrary to expectation, we found by electron microscopy and biochemical approaches that endogenous Bcl-x(L) also localized to inner mitochondrial cristae. Two-photon microscopy of cultured neurons revealed large fluctuations in inner mitochondrial membrane potential when Bcl-x(L) was genetically deleted or pharmacologically inhibited, indicating increased total ion flux into and out of mitochondria. Computational, biochemical, and genetic evidence indicated that Bcl-x(L) reduces futile ion flux across the inner mitochondrial membrane to prevent a wasteful drain on cellular resources, thereby preventing an energetic crisis during stress. Given that F(1)F(O)-ATP synthase directly affects mitochondrial membrane potential and having identified the mitochondrial ATP synthase β subunit in a screen for Bcl-x(L)-binding partners, we tested and found that Bcl-x(L) failed to protect β subunit-deficient yeast. Thus, by bolstering mitochondrial energetic capacity, Bcl-x(L) may contribute importantly to cell survival independently of other Bcl-2 family proteins.

  18. Interphase FISH detection of BCL2 rearrangement in follicular lymphoma using breakpoint-flanking probes

    NARCIS (Netherlands)

    Vaandrager, J W; Schuuring, E; Raap, T; Philippo, K; Kleiverda, K; Kluin, P

    Rearrangement of the BCL2 gene is an important parameter for the differential diagnosis of non-Hodgkin lymphomas. Although a relatively large proportion of breakpoints is clustered, many are missed by standard PCR. A FISH assay is therefore desired. Up to now, a lack of probes flanking the BCL2 gene

  19. The anti-apoptotic members of the Bcl-2 family are attractive tumor-associated antigens

    DEFF Research Database (Denmark)

    Straten, Per thor; Andersen, Mads Hald; Andersen, Mads Hald

    2010-01-01

    Anti-apoptotic members of the Bcl-2 family (Bcl-2, Bcl-X(L) and Mcl-2) are pivotal regulators of apoptotic cell death. They are all highly overexpressed in cancers of different origin in which they enhance the survival of the cancer cells. Consequently, they represent prime candidates for anti......-cancer therapy and specific antisense oligonucleotides or small molecule inhibitors have shown broad anti-cancer activities in pre-clinical models and are currently tested in clinical trials. In addition, immune-mediated tumor destruction is emerging as an interesting modality to treat cancer patients. Notably......, spontaneous cellular immune responses against the Bcl-2 family proteins have been identified as frequent features in cancer patients underscoring that these proteins are natural targets for the immune system. Thus, Bcl-2 family may serve as an important and widely applicable target for anti...

  20. Prognostic impact of concurrent MYC and BCL6 rearrangements and expression in de novo diffuse large B-cell lymphoma

    DEFF Research Database (Denmark)

    Ye, Qing; Xu-Monette, Zijun Y; Tzankov, Alexandar

    2016-01-01

    Double-hit B-cell lymphoma is a common designation for a group of tumors characterized by concurrent translocations of MYC and BCL2, BCL6, or other genes. The prognosis of concurrent MYC and BCL6 translocations is not well known. In this study, we assessed rearrangements and expression of MYC, BCL2...... with MYC translocation (observed in 2.0% of diffuse large B-cell lymphoma) predicted poorer survival in diffuse large B-cell lymphoma patients. Diffuse large B-cell lymphoma patients with MYC/BCL6 co-expression did have significantly poorer survival, however, MYC/BCL6 co-expression had no effect...... on prognosis in the absence of MYC/BCL2 co-expression, and had no additive impact in MYC+/BCL2+ cases. The isolated MYC+/BCL6+/BCL2- subset, more frequent in germinal center B-cell like diffuse large B-cell lymphoma, had significantly better survival compared with the isolated MYC+/BCL2+/BCL6- subset (more...

  1. High Ki67/BCL2 index is associated with worse outcome in early stage breast cancer.

    Science.gov (United States)

    Min, Kyueng-Whan; Kim, Dong-Hoon; Do, Sung-Im; Pyo, Jung-Soo; Chae, Seoung Wan; Sohn, Jin Hee; Kim, Kyungeun; Lee, Hyun Joo; Kim, Dong Hyun; Oh, Sukjoong; Choi, Seon Hyeong; Park, Yong Lai; Park, Chan Heun; Kwon, Mi Jung; Moon, Kyoung Min

    2016-12-01

    Breast cancers are heterogeneous, making it essential to recognise several biomarkers for cancer outcome predictions. Ki67 proliferation index and B cell lymphoma 2 (BCL2) proteins are widely used as prognostic indicators in many types of malignancies. While Ki67 is a marker of normal or tumour cell proliferation, BCL2 plays a central role in antiproliferative activities. A combination of these two biomarkers with contrary purposes can provide enhanced prognostic accuracy than an analysis using a single biomarker. We evaluated Ki67 and BCL2 expression with 203 cases of breast cancer. The relative expression of each biomarker named as Ki67/BCL2 index was divided into two groups (low vs high) with the use of area under receiver operating characteristic curves. There were significant correlations between Ki67/BCL2 index and clinicopathological findings such as age, tumour stage, size and necrosis, histological grade, extensive intraductal component, lymphatic and vascular invasion, oestrogen receptor, progesterone receptor, human epithelial growth factor receptor 2 and p53 expression (all pKi67/BCL2 index correlated with shorter disease-free survival and overall survival in patients with early stage invasive ductal carcinoma (all pKi67/BCL2 index should be considered as a prognostic predictor in patients with early stage invasive ductal carcinoma. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  2. Bcl-2 potentiates the maximal calcium uptake capacity of neural cell mitochondria.

    Science.gov (United States)

    Murphy, A N; Bredesen, D E; Cortopassi, G; Wang, E; Fiskum, G

    1996-01-01

    Expression of the human protooncogene bcl-2 protects neural cells from death induced by many forms of stress, including conditions that greatly elevate intracellular Ca2+. Considering that Bcl-2 is partially localized to mitochondrial membranes and that excessive mitochondrial Ca2+ uptake can impair electron transport and oxidative phosphorylation, the present study tested the hypothesis that mitochondria from Bcl-2-expressing cells have a higher capacity for energy-dependent Ca2+ uptake and a greater resistance to Ca(2+)-induced respiratory injury than mitochondria from cells that do not express this protein. The overexpression of bcl-2 enhanced the mitochondrial Ca2+ uptake capacity using either digitonin-permeabilized GT1-7 neural cells or isolated GT1-7 mitochondria by 1.7 and 3.9 fold, respectively, when glutamate and malate were used as respiratory substrates. This difference was less apparent when respiration was driven by the oxidation of succinate in the presence of the respiratory complex I inhibitor rotenone. Mitochondria from Bcl-2 expressors were also much more resistant to inhibition of NADH-dependent respiration caused by sequestration of large Ca2+ loads. The enhanced ability of mitochondria within Bcl-2-expressing cells to sequester large quantities of Ca2+ without undergoing profound respiratory impairment provides a plausible mechanism by which Bcl-2 inhibits certain forms of delayed cell death, including neuronal death associated with ischemia and excitotoxicity. PMID:8790427

  3. Identification of an HLA-A*0201 restricted Bcl2-derived epitope expressed on tumors

    DEFF Research Database (Denmark)

    Wang, Mingjun; Johansen, Britta; Nissen, Mogens H

    2006-01-01

    A large number of human tumor-associated antigen-derived peptides have been identified that are recognized by CTLs in a MHC-I restricted fashion. The apoptosis inhibitory protein Bcl2 is overexpressed in many human cancers as part of their neoplastic phenotype. Since inhibition or loss of Bcl2...... (Loukes) and a colon carcinoma (CCL220) cell line showed increased Bcl2 protein expression whereas the majority of tumor cell lines expressed proapoptotic proteins. Neither fibroblasts nor peripheral blood mononuclear cells showed Bcl2 expression. An HLA-A*0201 restricted CTL epitope was deduced in silica...... from the amino acid sequence of the Bcl2 protein and its binding affinity for HLA-A*0201 was confirmed using a biochemical binding assay. We here demonstrate that the 9-mer peptide Bcl2(85-93) induces specific CTL reactivity in immunized C57-A2K(b) or -A2D(b) tg mice. These Bcl2(85-93) specific CTLs...

  4. Bcl-xL transformed peanut (Arachis hypogaea L.) exhibits paraquat tolerance.

    Science.gov (United States)

    Chu, Y; Deng, X Y; Faustinelli, P; Ozias-Akins, P

    2008-01-01

    The human Bcl-xL gene was transformed into peanut cultivar Georgia Green via microprojectile bombardment. Following selection on hygromycin-containing medium and regeneration, eighty hygromycin-resistant callus clusters were recovered. Southern blot analysis of ten fertile lines revealed multiple insertions of the Bcl-xL transgene in most lines. Western blot analysis of primary plants and T1 progenies demonstrated detectable levels of Bcl-xL expression in four transgenic lines. We could not detect Bcl-xL protein in other tested lines even though transcripts were identified by RT-PCR and northern blot. Three of the western-positive transgenic lines either were sterile or the progenies lost the expressive copy of Bcl-xL. Only T1 progenies from line BX25-4-2a-19 continued to express an intermediate level of Bcl-xL. This line demonstrated paraquat tolerance at the 5 microM level. Tolerance to salt of T1 and T2 seeds from seven other transgenic lines also was tested, but no tolerance was found in these lines. A high level of Bcl-xL transgene expression may be deleterious to plant growth and development even though the gene may confer tolerance to other abiotic and biotic stresses such as drought and pathogens.

  5. Bcl11b mutations identified in murine lymphomas increase the proliferation rate of hematopoietic progenitor cells

    Directory of Open Access Journals (Sweden)

    Söderkvist Peter

    2007-10-01

    Full Text Available Abstract Background The telomeric region of mouse chromosome 12 has previously shown frequent allelic loss in murine lymphoma. The Bcl11b gene has been identified and suggested as a candidate tumor suppressor gene within this region. In this study, we aimed to elucidate whether Bcl11b is mutated in lymphomas with allelic loss, and whether the mutations we detected conferred any effect on cell proliferation and apoptosis. Methods Mouse lymphomas induced by 1,3-butadiene or 2',3'-dideoxycytidine were analysed for mutations in the Bcl11b gene using single strand conformation analysis and direct DNA sequencing. Effects on cell proliferation by the detected mutations were studied by expressing wild-type and mutant Bcl11b in the cytokine-dependent hematopoietic progenitor cell line FDC-P1, lacking endogenous Bcl11b expression. Results Missense and frameshift (FS mutations were identified in 7 of 47 tumors (15%. Interestingly, all mutations were found between amino acids 778–844 which encode the three C-terminal DNA-binding zinc fingers. In FDC-P1 cells, wild-type Bcl11b suppressed cell proliferation, whereas the mutated versions (S778N, K828T, Y844C and FS823 enhanced proliferation several-fold. Conclusion The genetic alterations detected in this study suggest that the three C-terminal zinc fingers of Bcl11b are important for the DNA-binding. Cell proliferation was suppressed by overexpression of wild-type Bcl11b but enhanced by mutant Bcl11b, indicating that these mutations may be an important contributing factor to lymphomagenesis in a subset of tumors.

  6. Melatonin may play a role in modulation of bax and bcl-2 expression levels to protect rat peripheral blood lymphocytes from gamma irradiation-induced apoptosis

    International Nuclear Information System (INIS)

    Mohseni, Mehran; Mihandoost, Ehsan; Shirazi, Alireza; Sepehrizadeh, Zargham; Bazzaz, Javad Tavakkoly; Ghazi-khansari, Mahmoud

    2012-01-01

    The close relationship between free radicals effects and apoptosis process has been proved. Melatonin has been reported as a direct free radical scavenger. We investigated the capability of melatonin in the modification of radiation-induced apoptosis and apoptosis-associated upstream regulators expression in rat peripheral blood lymphocytes. Rats were irradiated with a single whole body Cobalt 60-gamma radiation dose of 8 Gy at a dose rate of 101 cGy/min with or without melatonin pretreatments at different concentrations of 10 and 100 mg/kg body weight. The rats were divided into eight groups of control, irradiation-only, vehicle-only, vehicle plus irradiation, 10 mg/kg melatonin alone, 10 mg/kg melatonin plus irradiation, 100 mg/kg melatonin alone and 100 mg/kg melatonin plus irradiation. Rats were given an intraperitoneal (IP) injection of melatonin or the same volume of vehicle alone 1 h prior to irradiation. Blood samples were taken 4, 24, 48 and 72 h after irradiation for evaluation of flow cytometric analysis of apoptotic lymphocytes using Annexin V/PI assay and measurement of bax and bcl-2 expression using quantitative real-time PCR (RT 2 qPCR). Irradiation-only and vehicle plus irradiation showed an increase in the percentage of apoptotic lymphocytes significantly different from control group (P < 0.01), while melatonin pretreatments in a dose-dependent manner reduced it as compared with the irradiation-only and vehicle plus irradiation groups (P < 0.01) in all time points. This reduced apoptosis by melatonin was related to the downregulation of bax, upregulation of bcl-2, and therefore reduction of bax/bcl-2 ratio. Our results suggest that melatonin in these doses may provide modulation of bax and bcl-2 expression as well as bax/bcl-2 ratio to protect rat peripheral blood lymphocytes from gamma irradiation-induced apoptosis.

  7. Melatonin may play a role in modulation of bax and bcl-2 expression levels to protect rat peripheral blood lymphocytes from gamma irradiation-induced apoptosis

    Energy Technology Data Exchange (ETDEWEB)

    Mohseni, Mehran [Department of Radiology and Medical Physics, Faculty of Paramedicine, Kashan University of Medical Sciences, Kashan (Iran, Islamic Republic of); Mihandoost, Ehsan, E-mail: mihandoost.e@gmail.com [Department of Medical Radiation Engineering, Science and Research Branch, Islamic Azad University, Tehran (Iran, Islamic Republic of); Shirazi, Alireza [Department of Medical Physics and Biomedical Engineering, Faculty of Medicine, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Sepehrizadeh, Zargham [Department of Pharmaceutical Biotechnology, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Bazzaz, Javad Tavakkoly [Department of Medical Genetics, Faculty of Medicine, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Ghazi-khansari, Mahmoud [Department of Pharmacology, Faculty of Medicine, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of)

    2012-10-15

    The close relationship between free radicals effects and apoptosis process has been proved. Melatonin has been reported as a direct free radical scavenger. We investigated the capability of melatonin in the modification of radiation-induced apoptosis and apoptosis-associated upstream regulators expression in rat peripheral blood lymphocytes. Rats were irradiated with a single whole body Cobalt 60-gamma radiation dose of 8 Gy at a dose rate of 101 cGy/min with or without melatonin pretreatments at different concentrations of 10 and 100 mg/kg body weight. The rats were divided into eight groups of control, irradiation-only, vehicle-only, vehicle plus irradiation, 10 mg/kg melatonin alone, 10 mg/kg melatonin plus irradiation, 100 mg/kg melatonin alone and 100 mg/kg melatonin plus irradiation. Rats were given an intraperitoneal (IP) injection of melatonin or the same volume of vehicle alone 1 h prior to irradiation. Blood samples were taken 4, 24, 48 and 72 h after irradiation for evaluation of flow cytometric analysis of apoptotic lymphocytes using Annexin V/PI assay and measurement of bax and bcl-2 expression using quantitative real-time PCR (RT{sup 2}qPCR). Irradiation-only and vehicle plus irradiation showed an increase in the percentage of apoptotic lymphocytes significantly different from control group (P < 0.01), while melatonin pretreatments in a dose-dependent manner reduced it as compared with the irradiation-only and vehicle plus irradiation groups (P < 0.01) in all time points. This reduced apoptosis by melatonin was related to the downregulation of bax, upregulation of bcl-2, and therefore reduction of bax/bcl-2 ratio. Our results suggest that melatonin in these doses may provide modulation of bax and bcl-2 expression as well as bax/bcl-2 ratio to protect rat peripheral blood lymphocytes from gamma irradiation-induced apoptosis.

  8. Bcl-2 overexpression is associated with resistance to paclitaxel, but not gemcitabine, in multiple myeloma cells.

    Science.gov (United States)

    Gazitt, Y; Rothenberg, M L; Hilsenbeck, S G; Fey, V; Thomas, C; Montegomrey, W

    1998-10-01

    Multiple myeloma (MM) is an incurable disease despite an initial response-rate of >60% with conventional or high-dose chemotherapy using glucocorticosteroids (i.e. dexamethasone), or alkylating agents (i.e. melphalan). Although these agents are capable of inducing complete remission (CR) in >50% of MM patients, resistance develops rapidly, in >90% of patients, within 2 years of treatment. Therefore, there is a need for new drugs for the treatment of relapsing and refractory MM patients. Gemcitabine (GEM) is a pyrimidine analog that blocks DNA synthesis, whereas, paclitaxel (TAX) is a mitotic spindle poison that promotes microtubular aggregation. Since it appears that these two drugs have different cellular targets, we examined the effect of each drug individually for several parameters and for possible synergy. We studied the cytotoxic effect of TAX and GEM on MM cells expressing varying levels of the antiapoptotic protein bcl-2, which is overexpressed in the majority of myeloma cell from MM patients. We found that both drugs are cytotoxic by inducing apoptosis, however, the extent of apoptosis with TAX, but not with GEM was dependent on the levels of bcl-2 expression. We further investigated the effect of TAX and GEM on the cell cycle distribution and on the levels of bcl-2. The results indicate that the two drugs have different modes of action with respect to each parameter tested. TAX induced arrest of the cells in the G2/M phase of the cell cycle, regardless of bcl-2 levels, however, apoptosis was induced in mitotic cells expressing relatively low levels of bcl-2. In contrast, GEM caused apoptosis of cells in the S-phase, regardless of level of bcl-2 expression. A major difference between TAX and GEM was in their effects on the levels of bcl-2. Whereas, TAX induced an early downregulation of bcl-2 (only in the cells with relatively low levels of bcl-2), treatment with GEM did not affect bcl-2 levels. The effects of TAX on both the cell cycle and bcl-2 were

  9. Real world data on young patients with high-risk diffuse large B-cell lymphoma treated with R-CHOP or R-CHOEP - MYC, BCL2 and BCL6 as prognostic biomarkers

    DEFF Research Database (Denmark)

    Pedersen, Mette Ølgod; Gang, Anne Ortved; Brown, Peter

    2017-01-01

    BACKGROUND: Double expression of MYC and BCL2 proteins (DE) and double-hit MYC+BCL2/BCL6 translocations (DH) were established as important biomarkers in patients with diffuse large B-cell lymphoma (DLBCL) by the 2016 revision of the World Health Organization classification of lymphoid neoplasms......-CHOP or R-CHOEP were obtained from the Danish Lymphoma database (n = 159). Tumor samples were available from 103 patients. MYC and BCL2 proteins were analyzed with quantitative immunohistochemistry (IHC) using different cut off values. MYC-, BCL2- and BCL6-translocations were examined with fluorescent...... in situ hybridization (FISH). RESULTS: DE with MYC>75% and BCL2>85% was an independent negative prognostic marker of progression free survival (PFS) in patients treated with R-CHOP but not R-CHOEP (p

  10. MOMP, cell suicide as a BCL-2 family business.

    Science.gov (United States)

    Kalkavan, Halime; Green, Douglas R

    2018-01-01

    Apoptosis shapes development and differentiation, has a key role in tissue homeostasis, and is deregulated in cancer. In most cases, successful apoptosis is triggered by mitochondrial outer membrane permeabilization (MOMP), which defines the mitochondrial or intrinsic pathway and ultimately leads to caspase activation and protein substrate cleavage. The mitochondrial apoptotic pathway centered on MOMP is controlled by an intricate network of events that determine the balance of the cell fate choice between survival and death. Here we will review how MOMP proceeds and how the main effectors cytochrome c, a heme protein that has a crucial role in respiration, and second mitochondria-derived activator of caspase (SMAC), as well as other intermembrane space proteins, orchestrate caspase activation. Moreover, we discuss recent insights on the interplay of the upstream coordinators and initiators of MOMP, the BCL-2 family. This review highlights how our increasing knowledge on the regulation of critical checkpoints of apoptosis integrates with understanding of cancer development and has begun to translate into therapeutic clinical benefit.

  11. BCL6 modulates tonic BCR signaling in diffuse large B-cell lymphomas by repressing the SYK phosphatase, PTPROt.

    Science.gov (United States)

    Juszczynski, Przemyslaw; Chen, Linfeng; O'Donnell, Evan; Polo, Jose M; Ranuncolo, Stella M; Dalla-Favera, Riccardo; Melnick, Ari; Shipp, Margaret A

    2009-12-17

    Tonic B-cell receptor (BCR) signaling is a key survival pathway during normal B-cell ontogenesis and in a subset of diffuse large B-cell lymphomas (DLBCLs). We previously demonstrated that BCR-dependent DLBCL cell lines and primary tumors underwent apoptosis after treatment with an ATP-competitive inhibitor of the BCR-associated spleen tyrosine kinase (SYK). These "BCR-type" tumors also have more abundant expression of the transcriptional repressor, BCL6, and increased sensitivity to BCL6 inhibition. Herein, we evaluated potential connections between BCL6-mediated transcriptional repression and SYK-dependent BCR signaling. In transcriptionally profiled normal B-cell subsets (naive, germinal center, and memory B cells) and in primary DLBCLs, there were reciprocal patterns of expression of BCL6 and the SYK tyrosine phosphatase PTPROt. BCL6 repressed PTPROt transcription via a direct interaction with functional BCL6 binding sites in the PTPROt promoter. Enforced expression of BCL6 in normal naive B cells and RNAi-mediated depletion of BCL6 in germinal center B cells directly modulated PTPROt expression. In "BCR-type" DLBCLs, BCL6 depletion increased PTPROt expression and decreased phosphorylation of SYK and the downstream adaptor protein BLNK. Because BCL6 augments BCR signaling and BCL6 and SYK are both promising therapeutic targets in many DLBCLs, combined inhibition of these functionally related pathways warrants further study.

  12. U1 Adaptor Oligonucleotides Targeting BCL2 and GRM1 Suppress Growth of Human Melanoma Xenografts In Vivo

    Directory of Open Access Journals (Sweden)

    Rafal Goraczniak

    2013-01-01

    Full Text Available U1 Adaptor is a recently discovered oligonucleotide-based gene-silencing technology with a unique mechanism of action that targets nuclear pre-mRNA processing. U1 Adaptors have two distinct functional domains, both of which must be present on the same oligonucleotide to exert their gene-silencing function. Here, we present the first in vivo use of U1 Adaptors by targeting two different human genes implicated in melanomagenesis, B-cell lymphoma 2 (BCL2 and metabotropic glutamate receptor 1 (GRM1, in a human melanoma cell xenograft mouse model system. Using a newly developed dendrimer delivery system, anti-BCL2 U1 Adaptors were very potent and suppressed tumor growth at doses as low as 34 µg/kg with twice weekly intravenous (iv administration. Anti-GRM1 U1 Adaptors suppressed tumor xenograft growth with similar potency. Mechanism of action was demonstrated by showing target gene suppression in tumors and by observing that negative control U1 Adaptors with just one functional domain show no tumor suppression activity. The anti-BCL2 and anti-GRM1 treatments were equally effective against cell lines harboring either wild-type or a mutant V600E B-RAF allele, the most common mutation in melanoma. Treatment of normal immune-competent mice (C57BL6 indicated no organ toxicity or immune stimulation. These proof-of-concept studies represent an in-depth (over 800 mice in ~108 treatment groups validation that U1 Adaptors are a highly potent gene-silencing therapeutic and open the way for their further development to treat other human diseases.

  13. Metabolic reprogramming in cancer cells: glycolysis, glutaminolysis, and Bcl-2 proteins as novel therapeutic targets for cancer.

    Science.gov (United States)

    Li, Chunxia; Zhang, Guifeng; Zhao, Lei; Ma, Zhijun; Chen, Hongbing

    2016-01-20

    Nearly a century ago, Otto Warburg made the ground-breaking observation that cancer cells, unlike normal cells, prefer a seemingly inefficient mechanism of glucose metabolism: aerobic glycolysis, a phenomenon now referred to as the Warburg effect. The finding that rapidly proliferating cancer cells favors incomplete metabolism of glucose, producing large amounts of lactate as opposed to synthesizing ATP to sustain cell growth, has confounded scientists for years. Further investigation into the metabolic phenotype of cancer has expanded our understanding of this puzzling conundrum, and has opened new avenues for the development of anti-cancer therapies. Enhanced glycolytic flux is now known to allow for increased synthesis of intermediates for sustaining anabolic pathways critical for cancer cell growth. Alongside the increase in glycolysis, cancer cells transform their mitochondria into synthesis machines supported by augmented glutaminolysis, supplying lipid production, amino acid synthesis, and the pentose phosphate pathways. Inhibition of several of the key enzymes involved in these pathways has been demonstrated to effectively obstruct cancer cell growth and multiplication, sensitizing them to apoptosis. The modulation of various regulatory proteins involved in metabolic processes is central to cancerous reprogramming of metabolism. The finding that members of one of the major protein families involved in cell death regulation also aberrantly regulated in cancers, the Bcl-2 family of proteins, are also critical mediators of metabolic pathways, provides strong evidence for the importance of the metabolic shift to cancer cell survival. Targeting the anti-apoptotic members of the Bcl-2 family of proteins is proving to be a successful way to selectively target cancer cells and induce apoptosis. Further understanding of how cancer cells modify metabolic regulation to increase channeling of substrates into biosynthesis will allow for the discovery of novel drug

  14. The Role of BCL2 Family of Apoptosis Regulator Proteins in Acute and Chronic Leukemias

    Directory of Open Access Journals (Sweden)

    Flora Tzifi

    2012-01-01

    Full Text Available The disturbance of apoptosis molecular signaling pathways is involved in carcinogenesis. BCL2 family of proteins is the hallmark of apoptosis regulation. In the last decade, new members of BCL2 gene family were discovered and cloned and were found to be differentially expressed in many types of cancer. BCL2 protein family, through its role in regulation of apoptotic pathways, is possibly related to cancer pathophysiology and resistance to conventional chemotherapy. It is well known that leukemias are haematopoietic malignancies characterized by biological diversity, varied cytogenetics, different immunophenotype profiles, and diverse outcome. Current research focuses on the prognostic impact and specific role of these proteins in the pathogenesis of leukemias. The understanding of the molecular pathways that participate in the biology of leukemias may lead to the design of new therapies which may improve patients' survival. In the present paper, we describe current knowledge on the role of BCL2 apoptosis regulator proteins in acute and chronic leukemias.

  15. Extracellular administration of BCL2 protein reduces apoptosis and improves survival in a murine model of sepsis.

    Directory of Open Access Journals (Sweden)

    Akiko Iwata

    2011-02-01

    Full Text Available Severe sepsis and septic shock are major causes of morbidity and mortality worldwide. In experimental sepsis there is prominent apoptosis of various cell types, and genetic manipulation of death and survival pathways has been shown to modulate organ injury and survival.We investigated the effect of extracellular administration of two anti-apoptotic members of the BCL2 (B-cell lymphoma 2 family of intracellular regulators of cell death in a murine model of sepsis induced by cecal ligation and puncture (CLP. We show that intraperitoneal injection of picomole range doses of recombinant human (rh BCL2 or rhBCL2A1 protein markedly improved survival as assessed by surrogate markers of death. Treatment with rhBCL2 or rhBCL2A1 protein significantly reduced the number of apoptotic cells in the intestine and heart following CLP, and this was accompanied by increased expression of endogenous mouse BCL2 protein. Further, mice treated with rhBCL2A1 protein showed an increase in the total number of neutrophils in the peritoneum following CLP with reduced neutrophil apoptosis. Finally, although neither BCL2 nor BCL2A1 are a direct TLR2 ligand, TLR2-null mice were not protected by rhBCL2A1 protein, indicating that TLR2 signaling was required for the protective activity of extracellularly adminsitered BCL2A1 protein in vivo.Treatment with rhBCL2A1 or rhBCL2 protein protects mice from sepsis by reducing apoptosis in multiple target tissues, demonstrating an unexpected, potent activity of extracellularly administered BCL2 BH4-domain proteins.

  16. Characterization of apoptosis and autophagy through Bcl-2 and Beclin-1 immunoexpression in gestational trophoblastic disease

    OpenAIRE

    Wargasetia, Teresa Liliana; Shahib, Nurhalim; Martaadisoebrata, Djamhoer; Dhianawaty, Diah; Hernowo, Bethy

    2015-01-01

    Background: The pathogenesis of Gestational Trophoblastic Disease (GTD) is not clearly known. Objective: In this study, immunoexpression of proteins Bcl-2 and Beclin-1 in trophoblastic lesions and normal trophoblastic tissue was conducted to study the mechanism of apoptotic and autophagic cell death that is expected to complete the study of GTD pathogenesis. Materials and Methods: Bcl-2 and Beclin-1 immunoexpression were studied on complete hydatidiform mole, partial hydatidiform mole, ...

  17. EGFR and Bcl-2 in gastric mucosa of children infected with Helicobacter pylori

    Directory of Open Access Journals (Sweden)

    Ewa Ryszczuk

    2016-03-01

    Full Text Available Aim: The aim of the study was to evaluate the expression of EGFR and Bcl-2 proteins as inhibitory markers of apoptosis in surface epithelial cells and gland cells of antral gastric mucosa in children infected with Helicobacter pylori according to the severity and activity of antral gastritis and to assess the correlation between the number of cells expressing EGFR and the number of cells expressing Bcl-2 in H. pylori infected children.Materials and methods: The study included 44 children: 68.2% with chronic gastritis and positive IgG against H. pylori, and 31.8% with functional disorders of the gastrointestinal tract and with normal IgG against H. pylori. The evaluation of EGFR expression in gastric mucosa was performed immunohistochemically using monoclonal mouse anti-EGFR antibody. The polyclonal antibody was used to determine the expression of anti-Bcl-2.Results: A significant increase in the number of cells expressing EGFR and Bcl-2 protein was found in the epithelial cells in severe as well as mild and moderate gastritis in the group of children infected with H. pylori. An increase in the number of cells expressing EGFR and Bcl-2 protein was also found in the epithelial cells in group I according to the activity of gastritis. There was a statistically significant positive correlation between the numbers of cells expressing EGFR and Bcl-2 in H. pylori infected children.Conclusion: Increased expression of EGFR and Bcl-2 proteins in the epithelial cells and a statistically significant positive correlation between the numbers of cells expressing EGFR and Bcl-2 in H. pylori infected children could suggest increased regeneration abilities of gastric mucosa.

  18. BCL-2 (-938C > A polymorphism is associated with breast cancer susceptibility

    Directory of Open Access Journals (Sweden)

    Liang Faming

    2011-04-01

    Full Text Available Abstract Background BCL-2 (B-cell leukemia/lymphoma 2 gene has been demonstrated to be associated with breast cancer development and a single nucleotide polymorphism (SNP; -938C > A has been identified recently. To investigate whether this polymorphism functions as a modifier of breast cancer development, we analyzed the distribution of genotype frequency, as well as the association of genotype with clinicopathological characteristics. Furthermore, we also studied the effects of this SNP on Bcl-2 expression in vitro. Methods We genotyped the BCL-2 (-938C > A in 114 patients and 107 controls, and analyzed the estrogen receptor (ER, progestogen receptor (PR, C-erbB2 and Ki67 status with immunohistochemistry (IHC. Different Bcl-2 protein levels in breast cancer cell lines were determined using western blot. Logistic regression model was applied in statistical analysis. Results We found that homozygous AA genotype was associated with an increased risk (AA vs AC+CC by 2.37-fold for breast cancer development and significant association was observed between nodal status and different genotypes of BCL-2 (-938C > A (p = 0.014. AA genotype was more likely to develop into lobular breast cancer (p = 0.036. The result of western blot analysis indicated that allele A was associated with the lower level of Bcl-2 expression in breast cancer cell lines. Conclusions AA genotype of BCL-2 (-938C > A is associated with susceptibility of breast cancer, and this genotype is only associated with the nodal status and pathological diagnosis of breast cancer. The polymorphism has an effect on Bcl-2 expression but needs further investigation.

  19. A Urinary Bcl-2 Surface Acoustic Wave Biosensor for Early Ovarian Cancer Detection

    Directory of Open Access Journals (Sweden)

    Nathan D. Gallant

    2012-05-01

    Full Text Available In this study, the design, fabrication, surface functionalization and experimental characterization of an ultrasonic MEMS biosensor for urinary anti-apoptotic protein B-cell lymphoma 2 (Bcl-2 detection with sub ng/mL sensitivity is presented. It was previously shown that urinary Bcl-2 levels are reliably elevated during early and late stages of ovarian cancer. Our biosensor uses shear horizontal (SH surface acoustic waves (SAWs on surface functionalized ST-cut Quartz to quantify the mass loading change by protein adhesion to the delay path. SH-SAWs were generated and received by a pair of micro-fabricated interdigital transducers (IDTs separated by a judiciously designed delay path. The delay path was surface-functionalized with monoclonal antibodies, ODMS, Protein A/G and Pluronic F127 for optimal Bcl-2 capture with minimal non-specific adsorption. Bcl-2 concentrations were quantified by the resulting resonance frequency shift detected by a custom designed resonator circuit. The target sensitivity for diagnosis and identifying the stage of ovarian cancer was successfully achieved with demonstrated Bcl-2 detection capability of 500 pg/mL. It was also shown that resonance frequency shift increases linearly with increasing Bcl-2 concentration.

  20. Regulation of alternative splicing of Bcl-x by BC200 contributes to breast cancer pathogenesis

    Science.gov (United States)

    Singh, R; Gupta, S C; Peng, W-X; Zhou, N; Pochampally, R; Atfi, A; Watabe, K; Lu, Z; Mo, Y-Y

    2016-01-01

    BC200 is a long non-coding RNA (lncRNA) that has been implicated in the regulation of protein synthesis, yet whether dysregulation of BC200 contributes to the pathogenesis of human diseases remains elusive. In this study, we show that BC200 is upregulated in breast cancer; among breast tumor specimens there is a higher level of BC200 in estrogen receptor (ER) positive than in ER-negative tumors. Further experiments show that activation of estrogen signaling induces expression of BC200. To determine the significance of ER-regulated BC200 expression, we knockout (KO) BC200 by CRISPR/Cas9. BC200 KO suppresses tumor cell growth in vitro and in vivo by expression of the pro-apoptotic Bcl-xS isoform. Mechanistically, BC200 contains a 17-nucleotide sequence complementary to Bcl-x pre-mRNA, which may facilitate its binding to Bcl-x pre-mRNA and recruitment of heterogeneous nuclear ribonucleoprotein (hnRNP) A2/B1, a known splicing factor. Consequently, hnRNP A2/B1 interferes with association of Bcl-x pre-mRNA with the Bcl-xS-promoting factor Sam68, leading to a blockade of Bcl-xS expression. Together, these results suggest that BC200 plays an oncogenic role in breast cancer. Thus, BC200 may serve as a prognostic marker and possible target for attenuating deregulated cell proliferation in estrogen-dependent breast cancer. PMID:27277684

  1. Bcl-2 overexpression prevents {sup 99m}Tc-MIBI uptake in breast cancer cell lines

    Energy Technology Data Exchange (ETDEWEB)

    Aloj, Luigi; Zannetti, Antonella; Caraco, Corradina; Del Vecchio, Silvana [Istituto di Biostrutture e Bioimmagini, Sezione di Bioimmagini, Consiglio Nazionale delle Ricerche (CNR), Via S. Pansini 5, Edificio 10, 80131, Napoli (Italy); Salvatore, Marco [Dipartimento di Scienze Biomorfologiche e Funzionali, Universita' ' ' Federico II' ' , Napoli (Italy)

    2004-04-01

    We have previously shown a correlation between the absence of technetium-99m methoxyisobutylisonitrile ({sup 99m}Tc-MIBI) uptake and overexpression of the anti-apoptotic protein Bcl-2 in human breast carcinoma. To establish a direct cause-effect relationship between Bcl-2 overexpression and reduced {sup 99m}Tc-MIBI uptake, MCF-7 and T47D breast cancer cell lines were stably transfected with the human Bcl-2 gene to increase intracellular protein levels and tested for {sup 99m}Tc-MIBI uptake. All clones overexpressing Bcl-2 showed a dramatic reduction of {sup 99m}Tc-MIBI uptake as compared with mock transfected control cells. Tracer uptake was promptly and partially restored by induction of apoptosis with staurosporine treatment. After 4.5 h of staurosporine treatment, a tenfold increase in {sup 99m}Tc-MIBI uptake was observed in treated as compared with untreated Bcl-2 overexpressing cells. Our findings provide a rational basis for the development of an in vivo test to detect Bcl-2 overexpression in human tumours. (orig.)

  2. The Bcl6–SMRT/NCoR cistrome represses inflammation to attenuate atherosclerosis

    Science.gov (United States)

    Barish, Grant D.; Yu, Ruth T.; Karunasiri, Malith S.; Becerra, Diana; Kim, Jason; Tseng, Tiffany W.; Tai, Li-Jung; LeBlanc, Matthias; Diehl, Cody; Cerchietti, Leandro; Miller, Yury I.; Witztum, Joseph L.; Melnick, Ari M.; Dent, Alexander L.; Tangirala, Rajendra K.; Evans, Ronald M.

    2012-01-01

    SUMMARY Chronic inflammation is a hallmark of atherosclerosis, but its transcriptional underpinnings are poorly understood. We show that the transcriptional repressor Bcl6 is an anti-inflammatory regulator whose loss in bone marrow of Ldlr−/− mice results in severe atherosclerosis and xanthomatous tendonitis, a virtually pathognomonic complication in patients with familial hypercholesterolemia. Disruption of the interaction between Bcl6 and SMRT or NCoR with a peptide inhibitor in vitro recapitulated atherogenic gene changes in mice transplanted with Bcl6-deficient bone marrow, pointing to these cofactors as key mediators of Bcl6 inflammatory suppression. Using ChIP-seq, we reveal the SMRT and NCoR co-repressor cistromes, each consisting of over 30,000 binding sites with a nearly 50% overlap. While the complete cistromes identify a diversity of signaling pathways, the Bcl6-bound sub-cistromes for each co-repressor are highly enriched for NF-κB-driven inflammatory and tissue remodeling genes. These results reveal that Bcl6-SMRT/NCoR complexes constrain immune responses and contribute to the prevention of atherosclerosis. PMID:22465074

  3. Antiviral Properties of Chemical Inhibitors of Cellular Anti-Apoptotic Bcl-2 Proteins.

    Science.gov (United States)

    Bulanova, Daria; Ianevski, Aleksandr; Bugai, Andrii; Akimov, Yevhen; Kuivanen, Suvi; Paavilainen, Henrik; Kakkola, Laura; Nandania, Jatin; Turunen, Laura; Ohman, Tiina; Ala-Hongisto, Hanna; Pesonen, Hanna M; Kuisma, Marika S; Honkimaa, Anni; Walton, Emma L; Oksenych, Valentyn; Lorey, Martina B; Guschin, Dmitry; Shim, Jungmin; Kim, Jinhee; Than, Thoa T; Chang, So Young; Hukkanen, Veijo; Kulesskiy, Evgeny; Marjomaki, Varpu S; Julkunen, Ilkka; Nyman, Tuula A; Matikainen, Sampsa; Saarela, Jani S; Sane, Famara; Hober, Didier; Gabriel, Gülsah; De Brabander, Jef K; Martikainen, Miika; Windisch, Marc P; Min, Ji-Young; Bruzzone, Roberto; Aittokallio, Tero; Vähä-Koskela, Markus; Vapalahti, Olli; Pulk, Arto; Velagapudi, Vidya; Kainov, Denis E

    2017-09-25

    Viral diseases remain serious threats to public health because of the shortage of effective means of control. To combat the surge of viral diseases, new treatments are urgently needed. Here we show that small-molecules, which inhibit cellular anti-apoptotic Bcl-2 proteins (Bcl-2i), induced the premature death of cells infected with different RNA or DNA viruses, whereas, at the same concentrations, no toxicity was observed in mock-infected cells. Moreover, these compounds limited viral replication and spread. Surprisingly, Bcl-2i also induced the premature apoptosis of cells transfected with viral RNA or plasmid DNA but not of mock-transfected cells. These results suggest that Bcl-2i sensitizes cells containing foreign RNA or DNA to apoptosis. A comparison of the toxicity, antiviral activity, and side effects of six Bcl-2i allowed us to select A-1155463 as an antiviral lead candidate. Thus, our results pave the way for the further development of Bcl-2i for the prevention and treatment of viral diseases.

  4. Bcl-2 overexpression prevents 99mTc-MIBI uptake in breast cancer cell lines

    International Nuclear Information System (INIS)

    Aloj, Luigi; Zannetti, Antonella; Caraco, Corradina; Del Vecchio, Silvana; Salvatore, Marco

    2004-01-01

    We have previously shown a correlation between the absence of technetium-99m methoxyisobutylisonitrile ( 99m Tc-MIBI) uptake and overexpression of the anti-apoptotic protein Bcl-2 in human breast carcinoma. To establish a direct cause-effect relationship between Bcl-2 overexpression and reduced 99m Tc-MIBI uptake, MCF-7 and T47D breast cancer cell lines were stably transfected with the human Bcl-2 gene to increase intracellular protein levels and tested for 99m Tc-MIBI uptake. All clones overexpressing Bcl-2 showed a dramatic reduction of 99m Tc-MIBI uptake as compared with mock transfected control cells. Tracer uptake was promptly and partially restored by induction of apoptosis with staurosporine treatment. After 4.5 h of staurosporine treatment, a tenfold increase in 99m Tc-MIBI uptake was observed in treated as compared with untreated Bcl-2 overexpressing cells. Our findings provide a rational basis for the development of an in vivo test to detect Bcl-2 overexpression in human tumours. (orig.)

  5. Pan-Cancer Analysis Links PARK2 to BCL-XL-Dependent Control of Apoptosis

    Directory of Open Access Journals (Sweden)

    Yongxing Gong

    2017-02-01

    Full Text Available Mutation of the PARK2 gene can promote both Parkinson's Disease and cancer, yet the underlying mechanisms of how PARK2 controls cellular physiology is incompletely understood. Here, we show that the PARK2 tumor suppressor controls the apoptotic regulator BCL-XL and modulates programmed cell death. Analysis of approximately 10,000 tumor genomes uncovers a striking pattern of mutual exclusivity between PARK2 genetic loss and amplification of BCL2L1, implicating these genes in a common pathway. PARK2 directly binds to and ubiquitinates BCL-XL. Inactivation of PARK2 leads to aberrant accumulation of BCL-XL both in vitro and in vivo, and cancer-specific mutations in PARK2 abrogate the ability of the ubiquitin E3 ligase to target BCL-XL for degradation. Furthermore, PARK2 modulates mitochondrial depolarization and apoptosis in a BCL-XL-dependent manner. Thus, like genes at the nodal points of growth arrest pathways such as p53, the PARK2 tumor suppressor is able to exert its antiproliferative effects by regulating both cell cycle progression and programmed cell death.

  6. IRBIT controls apoptosis by interacting with the Bcl-2 homolog, Bcl2l10, and by promoting ER-mitochondria contact.

    Science.gov (United States)

    Bonneau, Benjamin; Ando, Hideaki; Kawaai, Katsuhiro; Hirose, Matsumi; Takahashi-Iwanaga, Hiromi; Mikoshiba, Katsuhiko

    2016-12-20

    IRBIT is a molecule that interacts with the inositol 1,4,5-trisphosphate (IP 3 )-binding pocket of the IP 3 receptor (IP 3 R), whereas the antiapoptotic protein, Bcl2l10, binds to another part of the IP 3 -binding domain. Here we show that Bcl2l10 and IRBIT interact and exert an additive inhibition of IP 3 R in the physiological state. Moreover, we found that these proteins associate in a complex in mitochondria-associated membranes (MAMs) and that their interplay is involved in apoptosis regulation. MAMs are a hotspot for Ca 2+ transfer between endoplasmic reticulum (ER) and mitochondria, and massive Ca 2+ release through IP 3 R in mitochondria induces cell death. We found that upon apoptotic stress, IRBIT is dephosphorylated, becoming an inhibitor of Bcl2l10. Moreover, IRBIT promotes ER mitochondria contact. Our results suggest that by inhibiting Bcl2l10 activity and promoting contact between ER and mitochondria, IRBIT facilitates massive Ca 2+ transfer to mitochondria and promotes apoptosis. This work then describes IRBIT as a new regulator of cell death.

  7. Maturation stage of T-cell acute lymphoblastic leukemia determines BCL-2 versus BCL-XL dependence and sensitivity to ABT-199.

    Science.gov (United States)

    Chonghaile, Triona Ni; Roderick, Justine E; Glenfield, Cian; Ryan, Jeremy; Sallan, Stephen E; Silverman, Lewis B; Loh, Mignon L; Hunger, Stephen P; Wood, Brent; DeAngelo, Daniel J; Stone, Richard; Harris, Marian; Gutierrez, Alejandro; Kelliher, Michelle A; Letai, Anthony

    2014-09-01

    Acute lymphoblastic leukemia (ALL) is a hematopoietic malignancy derived from immature B-lymphoid and T-lymphoid cells (T-ALL). In T-ALL, there is an early T-cell progenitor (ETP) subgroup that has a very high risk for relapse. In this study, we used mitochondrial BH3 profiling to determine antiapoptotic protein dependencies in T-ALL. We found that T-ALL cell lines and primary patient samples are dependent upon BCL-XL, except when the cancer bears an ETP phenotype, in which case it is BCL-2 dependent. These distinctions directly relate to differential sensitivity to the BH3 mimetics ABT-263 and ABT-199, both in vitro and in vivo. We thus describe for the first time a change of antiapoptotic protein dependence that is related to the differentiation stage of the leukemic clone. Our findings demonstrate that BCL-2 is a clinically relevant target for therapeutic intervention with ABT-199 in ETP-ALL. ETP T-ALL is a treatment-resistant subtype of T-ALL for which novel targeted therapies are urgently needed. We have discovered, through BH3 profiling, that ETP-ALL is BCL-2 dependent and is very sensitive to in vitro and in vivo treatment with ABT-199, a drug well tolerated in clinical trials. ©2014 American Association for Cancer Research.

  8. MLL-Rearranged Acute Lymphoblastic Leukemias Activate BCL-2 through H3K79 Methylation and Are Sensitive to the BCL-2-Specific Antagonist ABT-199.

    Science.gov (United States)

    Benito, Juliana M; Godfrey, Laura; Kojima, Kensuke; Hogdal, Leah; Wunderlich, Mark; Geng, Huimin; Marzo, Isabel; Harutyunyan, Karine G; Golfman, Leonard; North, Phillip; Kerry, Jon; Ballabio, Erica; Chonghaile, Triona Ní; Gonzalo, Oscar; Qiu, Yihua; Jeremias, Irmela; Debose, LaKiesha; O'Brien, Eric; Ma, Helen; Zhou, Ping; Jacamo, Rodrigo; Park, Eugene; Coombes, Kevin R; Zhang, Nianxiang; Thomas, Deborah A; O'Brien, Susan; Kantarjian, Hagop M; Leverson, Joel D; Kornblau, Steven M; Andreeff, Michael; Müschen, Markus; Zweidler-McKay, Patrick A; Mulloy, James C; Letai, Anthony; Milne, Thomas A; Konopleva, Marina

    2015-12-29

    Targeted therapies designed to exploit specific molecular pathways in aggressive cancers are an exciting area of current research. Mixed Lineage Leukemia (MLL) mutations such as the t(4;11) translocation cause aggressive leukemias that are refractory to conventional treatment. The t(4;11) translocation produces an MLL/AF4 fusion protein that activates key target genes through both epigenetic and transcriptional elongation mechanisms. In this study, we show that t(4;11) patient cells express high levels of BCL-2 and are highly sensitive to treatment with the BCL-2-specific BH3 mimetic ABT-199. We demonstrate that MLL/AF4 specifically upregulates the BCL-2 gene but not other BCL-2 family members via DOT1L-mediated H3K79me2/3. We use this information to show that a t(4;11) cell line is sensitive to a combination of ABT-199 and DOT1L inhibitors. In addition, ABT-199 synergizes with standard induction-type therapy in a xenotransplant model, advocating for the introduction of ABT-199 into therapeutic regimens for MLL-rearranged leukemias. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  9. BCL11B is frequently downregulated in HTLV-1-infected T-cells through Tax-mediated proteasomal degradation.

    Science.gov (United States)

    Permatasari, Happy Kurnia; Nakahata, Shingo; Ichikawa, Tomonaga; Morishita, Kazuhiro

    2017-08-26

    Human T-cell leukemia virus type 1 (HTLV-1) is a causative agent of adult T-cell leukemia-lymphoma (ATLL). The HTLV-1-encoded protein Tax plays important roles in the proliferation of HTLV-1-infected T-cells by affecting cellular proteins. In this study, we showed that Tax transcriptionally and post-transcriptionally downregulates the expression of the tumor suppressor gene B-cell leukemia/lymphoma 11B (BCL11B), which encodes a lymphoid-related transcription factor. BCL11B expression was downregulated in HTLV-1-infected T-cell lines at the mRNA and protein levels, and forced expression of BCL11B suppressed the proliferation of these cells. The proteasomal inhibitor MG132 increased BCL11B expression in HTLV-1-infected cell lines, and colocalization of Tax with BCL11B was detected in the cytoplasm of HTLV-1-infected T-cells following MG132 treatment. shRNA knock-down of Tax expression also increased the expression of BCL11B in HTLV-1-infected cells. Moreover, we found that Tax physically binds to BCL11B protein and induces the polyubiquitination of BCL11B and proteasome-dependent degradation of BCL11B. Thus, inactivation of BCL11B by Tax protein may play an important role in the Tax-mediated leukemogenesis. Copyright © 2017 Elsevier Inc. All rights reserved.

  10. Room temperature inductively coupled plasma etching of InAs/InSb in BCl 3/Cl 2/Ar

    KAUST Repository

    Sun, Jian

    2012-10-01

    Inductively coupled plasma (ICP) etching of InAs and InSb at room temperature has been investigated using BCl 3/Cl 2/Ar plasma. Specifically, the etch rate and post-etching surface morphology were investigated as functions of the gas composition, ICP power, process pressure, and RF chuck power. An optimized process has been developed, yielding anisotropic etching and very smooth surfaces with roughnesses of 0.25 nm for InAs, and 0.57 nm for InSb, which is comparable with the surface of epi-ready polished wafers. The process provides moderate etching rates of 820 /min for InAs and 2800 /min for InSb, and the micro-masking effect is largely avoided. © 2012 Elsevier B.V. All rights reserved.

  11. Bcl-XL-templated assembly of its own protein-protein interaction modulator from fragments decorated with thio acids and sulfonyl azides

    Science.gov (United States)

    Hu, Xiangdong; Sun, Jiazhi; Wang, Hong-Gang; Manetsch, Roman

    2008-01-01

    Protein-protein interactions have key importance in various biological processes and modulation of particular protein-protein interactions has been shown to have therapeutic effects. However, disrupting or modulating protein-protein interactions with low-molecular-weight compounds is extremely difficult due to the lack of deep binding pockets on protein surfaces. Herein we describe the development of an unprecedented lead synthesis and discovery method that generates only biologically active compounds from a library of reactive fragments. Using the protein Bcl-XL, a central regulator of programmed cell death, we demonstrated that an amidation reaction between thio acids and sulfonyl azides is applicable for Bcl-XL-templated assembly of inhibitory compounds. We have demonstrated for the first time that kinetic target-guided synthesis can be applied not only on enzymatic targets but also for the discovery of small molecules modulating protein-protein interactions. PMID:18811158

  12. BCL-2 inhibition with ABT-737 prolongs survival in an NRAS/BCL-2 mouse model of AML by targeting primitive LSK and progenitor cells.

    Science.gov (United States)

    Beurlet, Stephanie; Omidvar, Nader; Gorombei, Petra; Krief, Patricia; Le Pogam, Carole; Setterblad, Niclas; de la Grange, Pierre; Leboeuf, Christophe; Janin, Anne; Noguera, Maria-Elena; Hervatin, Florence; Sarda-Mantel, Laure; Konopleva, Marina; Andreeff, Michael; Tu, Andrea W; Fan, Alice C; Felsher, Dean W; Whetton, Anthony; Pla, Marika; West, Robert; Fenaux, Pierre; Chomienne, Christine; Padua, Rose Ann

    2013-10-17

    Myelodysplastic syndrome (MDS) transforms into an acute myelogenous leukemia (AML) with associated increased bone marrow (BM) blast infiltration. Using a transgenic mouse model, MRP8[NRASD12/hBCL-2], in which the NRAS:BCL-2 complex at the mitochondria induces MDS progressing to AML with dysplastic features, we studied the therapeutic potential of a BCL-2 homology domain 3 mimetic inhibitor, ABT-737. Treatment significantly extended lifespan, increased survival of lethally irradiated secondary recipients transplanted with cells from treated mice compared with cells from untreated mice, with a reduction of BM blasts, Lin-/Sca-1(+)/c-Kit(+), and progenitor populations by increased apoptosis of infiltrating blasts of diseased mice assessed in vivo by technicium-labeled annexin V single photon emission computed tomography and ex vivo by annexin V/7-amino actinomycin D flow cytometry, terminal deoxynucleotidyltransferase-mediated dUTP nick end labeling, caspase 3 cleavage, and re-localization of the NRAS:BCL-2 complex from mitochondria to plasma membrane. Phosphoprotein analysis showed restoration of wild-type (WT) AKT or protein kinase B, extracellular signal-regulated kinase 1/2 and mitogen-activated protein kinase patterns in spleen cells after treatment, which showed reduced mitochondrial membrane potential. Exon specific gene expression profiling corroborates the reduction of leukemic cells, with an increase in expression of genes coding for stem cell development and maintenance, myeloid differentiation, and apoptosis. Myelodysplastic features persist underscoring targeting of BCL-2-mediated effects on MDS-AML transformation and survival of leukemic cells.

  13. DAP-kinase-mediated phosphorylation on the BH3 domain of beclin 1 promotes dissociation of beclin 1 from Bcl-XL and induction of autophagy

    Science.gov (United States)

    Zalckvar, Einat; Berissi, Hanna; Mizrachy, Liat; Idelchuk, Yulia; Koren, Itay; Eisenstein, Miriam; Sabanay, Helena; Pinkas-Kramarski, Ronit; Kimchi, Adi

    2009-01-01

    Autophagy, an evolutionarily conserved process, has functions both in cytoprotective and programmed cell death mechanisms. Beclin 1, an essential autophagic protein, was recently identified as a BH3-domain-only protein that binds to Bcl-2 anti-apoptotic family members. The dissociation of beclin 1 from its Bcl-2 inhibitors is essential for its autophagic activity, and therefore should be tightly controlled. Here, we show that death-associated protein kinase (DAPK) regulates this process. The activated form of DAPK triggers autophagy in a beclin-1-dependent manner. DAPK phosphorylates beclin 1 on Thr 119 located at a crucial position within its BH3 domain, and thus promotes the dissociation of beclin 1 from Bcl-XL and the induction of autophagy. These results reveal a substrate for DAPK that acts as one of the core proteins of the autophagic machinery, and they provide a new phosphorylation-based mechanism that reduces the interaction of beclin 1 with its inhibitors to activate the autophagic machinery. PMID:19180116

  14. Expression of Bcl-2 and Bax in mouse renal tubules during kidney development.

    Science.gov (United States)

    Song, Xiao-Feng; Ren, Hao; Andreasen, Arne; Thomsen, Jesper Skovhus; Zhai, Xiao-Yue

    2012-01-01

    Bcl-2 and Bax play an important role in apoptosis regulation, as well as in cell adhesion and migration during kidney morphogenesis, which is structurally and functionally related to mitochondria. In order to elucidate the role of Bcl-2 and Bax during kidney development, it is essential to establish the exact location of their expression in the kidney. The present study localized their expression during kidney development. Kidneys from embryonic (E) 16-, 17-, 18-day-old mouse fetuses, and postnatal (P) 1-, 3-, 5-, 7-, 14-, 21-day-old pups were embedded in Epon. Semi-thin serial sections from two E17 kidneys underwent computer assisted 3D tubule tracing. The tracing was combined with a newly developed immunohistochemical technique, which enables immunohistochemistry on glutaraldehyde fixated plastic embedded sections. Thereby, the microstructure could be described in detail, and the immunochemistry can be performed using exactly the same sections. The study showed that Bcl-2 and Bax were strongly expressed in mature proximal convoluted tubules at all time points, less strongly expressed in proximal straight tubules, and only weakly in immature proximal tubules and distal tubules. No expression was detected in ureteric bud and other earlier developing structures, such as comma bodies, S shaped bodies, glomeruli, etc. Tubules expressing Bcl-2 only were occasionally observed. The present study showed that, during kidney development, Bcl-2 and Bax are expressed differently in the proximal and distal tubules, although these two tubule segments are almost equally equipped with mitochondria. The functional significance of the different expression of Bcl-2 and Bax in proximal and distal tubules is unknown. However, the findings of the present study suggest that the mitochondrial function differs between mature proximal tubules and in the rest of the tubules. The function of Bcl-2 and Bax during tubulogenesis still needs to be investigated.

  15. Quinacrine induces apoptosis in human leukemia K562 cells via p38 MAPK-elicited BCL2 down-regulation and suppression of ERK/c-Jun-mediated BCL2L1 expression

    International Nuclear Information System (INIS)

    Changchien, Jung-Jung; Chen, Ying-Jung; Huang, Chia-Hui; Cheng, Tian-Lu; Lin, Shinne-Ren; Chang, Long-Sen

    2015-01-01

    Although previous studies have revealed the anti-cancer activity of quinacrine, its effect on leukemia is not clearly resolved. We sought to explore the cytotoxic effect and mechanism of quinacrine action in human leukemia K562 cells. Quinacrine induced K562 cell apoptosis accompanied with ROS generation, mitochondrial depolarization, and down-regulation of BCL2L1 and BCL2. Upon exposure to quinacrine, ROS-mediated p38 MAPK activation and ERK inactivation were observed in K562 cells. Quinacrine-induced cell death and mitochondrial depolarization were suppressed by the p38MAPK inhibitor SB202190 and constitutively active MEK1 over-expression. Activation of p38 MAPK was shown to promote BCL2 degradation. Further, ERK inactivation suppressed c-Jun-mediated transcriptional expression of BCL2L1. Over-expression of BCL2L1 and BCL2 attenuated quinacrine-evoked mitochondrial depolarization and rescued the viability of quinacrine-treated cells. Taken together, our data indicate that quinacrine-induced K562 cell apoptosis is mediated through mitochondrial alterations triggered by p38 MAPK-mediated BCL2 down-regulation and suppression of ERK/c-Jun-mediated BCL2L1 expression. - Highlights: • Quinacrine induces K562 cell apoptosis via down-regulation of BCL2 and BCL2L1. • Quinacrine induces p38 MAPK activation and ERK inactivation in K562 cells. • Quinacrine elicits p38 MAPK-mediated BCL2 down-regulation. • Quinacrine suppresses ERK/c-Jun-mediated BCL2L1 expression

  16. A plant Bcl-2-associated athanogene is proteolytically activated to confer fungal resistance

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    Mehdi Kabbage

    2016-04-01

    Full Text Available The Bcl-2-associated athanogene (BAG family is a multifunctional group of proteins involved in numerous cellular functions ranging from apoptosis to tumorigenesis. These proteins are evolutionarily conserved and encode a characteristic region known as the BAG domain. BAGs function as adapter proteins forming complexes with signaling molecules and molecular chaperones. In humans, a role for BAG proteins has been suggested in tumor growth, HIV infection, and neurodegenerative diseases; as a result, the BAGs are attractive targets for therapeutic interventions, and their expression in cells may serve as a predictive tool for disease development. The Arabidopsis genome contains seven homologs of BAG family proteins (Figure 1, including four with a domain organization similar to animal BAGs (BAG1-4. The remaining three members (BAG5-7 contain a predicted calmodulin-binding motif near the BAG domain, a feature unique to plant BAG proteins that possibly reflects divergent mechanisms associated with plant-specific functions. As reported for animal BAGs, plant BAGs also regulate several stress and developmental processes (Figure 2. The recent article by Li et al. focuses on the role of BAG6 in plant innate immunity. This study shows that BAG6 plays a key role in basal plant defense against fungal pathogens. Importantly, this work further shows that BAG6 is proteolytically activated to induce autophagic cell death and resistance in plants. This finding underscores the importance of proteases in the execution of plant cell death, yet little is known about proteases and their substrates in plants.

  17. Genome-wide identification of Bcl11b gene targets reveals role in brain-derived neurotrophic factor signaling.

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    Bin Tang

    Full Text Available B-cell leukemia/lymphoma 11B (Bcl11b is a transcription factor showing predominant expression in the striatum. To date, there are no known gene targets of Bcl11b in the nervous system. Here, we define targets for Bcl11b in striatal cells by performing chromatin immunoprecipitation followed by high-throughput sequencing (ChIP-seq in combination with genome-wide expression profiling. Transcriptome-wide analysis revealed that 694 genes were significantly altered in striatal cells over-expressing Bcl11b, including genes showing striatal-enriched expression similar to Bcl11b. ChIP-seq analysis demonstrated that Bcl11b bound a mixture of coding and non-coding sequences that were within 10 kb of the transcription start site of an annotated gene. Integrating all ChIP-seq hits with the microarray expression data, 248 direct targets of Bcl11b were identified. Functional analysis on the integrated gene target list identified several zinc-finger encoding genes as Bcl11b targets, and further revealed a significant association of Bcl11b to brain-derived neurotrophic factor/neurotrophin signaling. Analysis of ChIP-seq binding regions revealed significant consensus DNA binding motifs for Bcl11b. These data implicate Bcl11b as a novel regulator of the BDNF signaling pathway, which is disrupted in many neurological disorders. Specific targeting of the Bcl11b-DNA interaction could represent a novel therapeutic approach to lowering BDNF signaling specifically in striatal cells.

  18. Is upregulation of BCL2 a determinant of tumor development driven by inactivation of CDH1/E-cadherin?

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    Inga Karch

    Full Text Available Inactivation of CDH1, encoding E-cadherin, promotes cancer initiation and progression. According to a newly proposed molecular mechanism, loss of E-cadherin triggers an upregulation of the anti-apoptotic oncoprotein BCL2. Conversely, reconstitution of E-cadherin counteracts overexpression of BCL2. This reciprocal regulation is thought to be critical for early tumor development. We determined the relevance of this new concept in human infiltrating lobular breast cancer (ILBC, the prime tumor entity associated with CDH1 inactivation. BCL2 expression was examined in human ILBC cell lines (IPH-926, MDA-MB-134, SUM-44 harboring deleterious CDH1 mutations. To test for an intact regulatory axis between E-cadherin and BCL2, wild-type E-cadherin was reconstituted in ILBC cells by ectopic expression. Moreover, BCL2 and E-cadherin were evaluated in primary invasive breast cancers and in synchronous lobular carcinomas in situ (LCIS. MDA-MB-134 and IPH-926 showed little or no BCL2 expression, while SUM-44 ILBC cells were BCL2-positive. Reconstitution of E-cadherin failed to impact on BCL2 expression in all cell lines tested. Primary ILBCs were almost uniformly E-cadherin-negative (97% and were frequently BCL2-negative (46%. When compared with an appropriate control group, ILBCs showed a trend towards an increased frequency of BCL2-negative cases (P = 0.064. In terminal duct-lobular units affected by LCIS, the E-cadherin-negative neoplastic component showed a similar or a reduced BCL2-immunoreactivity, when compared with the adjacent epithelium. In conclusion, upregulation of BCL2 is not involved in lobular breast carcinogenesis and is unlikely to represent an important determinant of tumor development driven by CDH1 inactivation.

  19. Homoharringtonine suppresses imatinib resistance via the Bcl-6/p53 pathway in chronic myeloid leukemia cell lines.

    Science.gov (United States)

    Wang, Qian; Ding, Wei; Ding, Yihan; Ma, Jingjing; Qian, Zhaoye; Shao, Jingxian; Li, Yufeng

    2017-06-06

    The anti-leukemic mechanism of homoharringtonine (HHT) differs from that of IM, and HHT is one of the most useful agents for use in patients with IM resistance or intolerance. The Bcl-6/p53 pathway has been shown to regulate the sensitivity of tumor cells to antitumor drugs. We tested whether HHT blocked the Bcl-6/p53 pathway in order to promote the apoptosis of IM-resistant cells in vitro and in vivo. Ph+ acute lymphoblastic leukemia (ALL) cells and IM-resistant chronic myeloid leukemia (CML) cells showed high expression of Bcl-6 protein. Bcl-6 mediated the upregulation of p53, and and Bcl-6 induced growth inhibition of IM-resistant cells as well as its apoptosis by targeting p53. In addition, Bcl-6 was downregulated moderately after HHT treatment in different cells. The Bcl-6 expression was significantly increased in patients with CML when compared with healthy subjects. Furthermore, the expression of Bcl-6 was higher in patients with CML-blastic phase (CML-BP) than in those with CML-chronic phase (CML-CP). The inhibitory effect of drugs on cell growth was detected by Cell Counting Kit-8 (CCK-8), The apoptosis rate and the cell cycle were investigated by flow cytometry. The expression of Bcl-6, p53, Bcl-2, caspase9, and caspase3 proteins was assayed by western blot, Real- Time PCR (qPCR) detect Bcl-6 and p53 mRNA. HHT can suppress the growth and induce apoptosis of IM-resistant cells, the mechanism of which is associated with blocking of the Bcl-6/p53 pathway. Our results could offer a theoretical explanation for HHT use in patients with IM resistance or intolerance.

  20. Inhibition of apoptosis by BCL2 prevents leukemic transformation of a murine myelodysplastic syndrome

    Science.gov (United States)

    Saw, Jesslyn; Jowett, Jeremy B. M.; Aplan, Peter D.; Strasser, Andreas; Jane, Stephen M.; Curtis, David J.

    2012-01-01

    Programmed cell death or apoptosis is a prominent feature of low-risk myelodysplastic syndromes (MDS), although the underlying mechanism remains controversial. High-risk MDS have less apoptosis associated with increased expression of the prosurvival BCL2-related proteins. To address the mechanism and pathogenic role of apoptosis and BCL2 expression in MDS, we used a mouse model resembling human MDS, in which the fusion protein NUP98-HOXD13 (NHD13) of the chromosomal translocation t(2;11)(q31;p15) is expressed in hematopoietic cells. Hematopoietic stem and progenitor cells from 3-month-old mice had increased rates of apoptosis associated with increased cell cycling and DNA damage. Gene expression profiling of these MDS progenitors revealed a specific reduction in Bcl2. Restoration of Bcl2 expression by a BCL2 transgene blocked apoptosis of the MDS progenitors, which corrected the macrocytic anemia. Blocking apoptosis also restored cell-cycle quiescence and reduced DNA damage in the MDS progenitors. We expected that preventing apoptosis would accelerate malignant transformation to acute myeloid leukemia (AML). However, contrary to expectations, preventing apoptosis of premalignant cells abrogated transformation to AML. In contrast to the current dogma that overcoming apoptosis is an important step toward cancer, this work demonstrates that gaining a survival advantage of premalignant cells may delay or prevent leukemic progression. PMID:22855610

  1. Clinical significance of P53 and Bcl-2 in acute myeloid leukemia patients of Eastern India

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    Geetaram Sahu

    2011-11-01

    Full Text Available The frequency of p53 and Bcl-2 protein expression in 100 newly diagnosed and 10 relapsed acute myeloid leukemia (AML patients was analyzed by immunocytochemistry (ICC. The Kaplan-Meier method was used for univariate and multivariate statistical analysis to assess the relationship between p53, Bcl-2 and clinico-hematologic feature with respect to overall survival (OS using SPSS statistical software. No statistical significance was found in univariate analysis (P=0.60. However, when the subgroups of patients (+1, +2, +3 and +4 were compared, expression of p53 and Bcl-2 protein (1-10%, 11- 30%, 31-50% and >50% was statistically significant (P<0.05. However, in multivariate analysis, p53, immunopositivity was independently associated with a shorter overall survival (OS (P=0.038 while Bcl-2 immunopositivity was associated with longer overall survival (OS (P=0.002. Our finding shows that p53 and Bcl-2 protein overexpression is a strong indicator of response to chemotherapy and overall survival. This study reports for the first time AML in patients from Eastern India.

  2. Characterization of a TK6-Bcl-xL gly-159-ala Human Lymphoblast Clone

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    Chyall, L.: Gauny, S.; Kronenberg, A.

    2006-01-01

    TK6 cells are a well-characterized human B-lymphoblast cell line derived from WIL-2 cells. A derivative of the TK6 cell line that was stably transfected to express a mutated form of the anti-apoptotic protein Bcl-xL (TK6-Bcl-xL gly-159- ala clone #38) is compared with the parent cell line. Four parameters were evaluated for each cell line: growth under normal conditions, plating efficiency, and frequency of spontaneous mutation to 6‑thioguanine resistance (hypoxanthine phosphoribosyl transferase locus) or trifluorothymidine resistance (thymidine kinase locus). We conclude that the mutated Bcl-xL protein did not affect growth under normal conditions, plating efficiency or spontaneous mutation frequencies at the thymidine kinase (TK) locus. Results at the hypoxanthine phosphoribosyl transferase (HPRT) locus were inconclusive. A mutant fraction for TK6‑Bcl-xL gly-159-ala clone #38 cells exposed to 150cGy of 160kVp x-rays was also calculated. Exposure to x-irradiation increased the mutant fraction of TK6‑Bcl-xL gly-159-ala clone #38 cells.

  3. The ab initio study of laser cooling of BBr and BCl.

    Science.gov (United States)

    Yang, Rong; Gao, Yufeng; Tang, Bin; Gao, Tao

    2015-01-21

    We investigate the feasibility of laser cooling BBr and BCl using ab initio quantum chemistry. The multi-reference configuration interaction method (MRCI) is used to calculate the ground state X(1)Σ(+) and the low-lying excited state A(1)Π, where Davidson modification with the Douglas-Kroll scalar relativistic correction is also taken into account. The calculated spectroscopic constants are in good agreement with available experimental values. The potential energy curves, permanent dipole moments (PDMs), transition dipole moments (TDMs) followed by Franck-Condon factors and radiative times for the transitions from the A(1)Π state to the ground state X(1)Σ(+) are obtained as well. The determined Franck-Condon factors are highly diagonally distributed and the evaluated radiative lifetimes are of the order of nanoseconds. Furthermore, the a(3)Π→ X(1)Σ(+) transitions of BBr and BCl are also strongly diagonal and the X(1)Σ(+)→ A(1)Π transitions perhaps can be followed by the X(1)Σ(+)→ a(3)Π transitions to attain a lower Doppler temperature. Long-range behavior of BBr and BCl has also been studied, and a double well is found in the A(1)Π state of BBr. The shallow long-range well might open up even more channels for laser cooling of BBr. The results demonstrate the possibility of laser cooling BBr and BCl, and provide a promising theoretical reference for further research on BBr and BCl.

  4. The studies on thyrocyte apoptosis and expression of Bcl-2 and Bax in Hashimoto's thyroiditis

    International Nuclear Information System (INIS)

    Zhao Yaping; Wang Jialing; Fan Zhiyong; Liu Zehong; Wu HeJun; Zhou Wei; Jia Meizhai

    2003-01-01

    To investigate the thyrocyte apoptosis, the expression of Bcl-2, Bax and the relationship between apoptosis and the pathogenesis in Hashimoto's thyroiditis (HT), 41 HT thyroid and 10 normal thyroid specimens were selected. The level of apoptosis was detected by TUNEL methods. The expression and distribution of Bcl-2 and Bax were detected using immunohistochemical methods and analyzed by Mias99 pathological image system. Immunohistochemical staining was carried out using S-P kit. The Result showed that an increased level of apoptosis was observed in Hashimoto's glands. The apoptosis mainly distributed in thyroid follicles destruction area. This was associated with increased Bax expression. The strongly positive Bcl-2 staining was observed in the thyrocyte of intact thyroid follicles. The ratios of positive granule area and total light density of Bcl-2 to those of Bax in HT thyroid follicle area were lower than those in normal thyroid. The apoptosis of thyrocyte induced by dysregulation of Bcl-2 and Bax may be involved in the pathogeneses of HT

  5. A new assay for the discovery of Bcl-XL inhibitors.

    Science.gov (United States)

    Pisoni, Cristina; Cimoli, Guido; Resconi, Anna; Losi, Daniele; Lorenzetti, Rolando; Parodi, Silvio; Carrano, Lucia

    2005-01-01

    The Bcl-2 family of antiapoptotic proteins is commonly over expressed in many types of human cancer and remains one of the few validated targets. Antiapoptotic family proteins such as Bcl-2 and Bcl-XL function, at least in part, by binding proapoptotic members such as Bax and Bak and thereby prevent release of the apoptotic cascade of events. "BH3-only" members of the family disrupt this interaction by binding, via their BH3 domain, to a hydrophobic pocket on the surface of the antiapoptotic members. Disruption of heterodimerization could be used to modulate cell death reinstating apoptosis in cancer cells. An affinity displacement assay based on Bcl-XL/BH3 interaction has been developed. This assay makes use of soluble His-tagged Bcl-XL and fluorescein tagged BH3. Binding is measured as fluorescence associated with magnetic beads. The assay was miniaturized to 96-well microtiter plates and can be employed in high throughput screening (HTS), in addition it is robust enough to be applied to microbial fermentation extracts.

  6. BH3 Profiling Reveals Selectivity by Herpesviruses for Specific Bcl-2 Proteins To Mediate Survival of Latently Infected Cells

    Science.gov (United States)

    Cojohari, Olesea; Burrer, Christine M.; Peppenelli, Megan A.; Abulwerdi, Fardokht A.; Nikolovska-Coleska, Zaneta

    2015-01-01

    Herpesviruses, including human cytomegalovirus (HCMV), Epstein-Barr virus (EBV), and Kaposi’s sarcoma-associated herpesvirus, establish latency by modulating or mimicking antiapoptotic Bcl-2 proteins to promote survival of carrier cells. BH3 profiling, which assesses the contribution of Bcl-2 proteins towards cellular survival, was able to globally determine the level of dependence on individual cellular and viral Bcl-2 proteins within latently infected cells. Moreover, BH3 profiling predicted the sensitivity of infected cells to small-molecule inhibitors of Bcl-2 proteins. PMID:25740993

  7. Domains of BclA, the major surface glycoprotein of the B. cereus exosporium: glycosylation patterns and role in spore surface properties.

    Science.gov (United States)

    Lequette, Yannick; Garénaux, Estelle; Combrouse, Typhaine; Dias, Thays Del Lima; Ronse, Annette; Slomianny, Christian; Trivelli, Xavier; Guerardel, Yann; Faille, Christine

    2011-08-01

    The role of the BclA domains of B. cereus ATCC 14579 was investigated in order to understand the phenomena involved in the interfacial processes occurring between spores and inert surfaces. This was done by (i) creating deletions in the collagen-like region (CLR) and the C-terminal domain (CTD) of BclA, (ii) building BclA proteins with various lengths in the CLR and (iii) modifying the hydrophobic upper surface in the CTD. First, it was demonstrated that the CLR was substituted by three residues already reported in the CLR of B. anthracis, viz. rhamnose, 3-O-methyl-rhamnose, and GalNH(2) residues, while the CTD was also substituted by two additional glycosyl residues, viz. 2-O-methyl-rhamnose and 2,4-O-methyl-rhamnose. Regarding the properties of the spores, both CLR and CTD contributed to the adhesion of the spores, which was estimated by measuring the resistance to detachment of spores adhered to stainless steel plates). CLR and CTD also impacted the hydrophobic character and isoelectric point of the spores. It was then shown that the resistance to detachment of the spores was not affected by the physicochemical properties, but by the CLR length and the presence of hydrophobic amino acids on the CTD.

  8. A targeted proteomics approach to the quantitative analysis of ERK/Bcl-2-mediated anti-apoptosis and multi-drug resistance in breast cancer.

    Science.gov (United States)

    Yang, Ting; Xu, Feifei; Sheng, Yuan; Zhang, Wen; Chen, Yun

    2016-10-01

    Apoptosis suppression caused by overexpression of anti-apoptotic proteins is a central factor to the acquisition of multi-drug resistance (MDR) in breast cancer. As a highly conserved anti-apoptotic protein, Bcl-2 can initiate an anti-apoptosis response via an ERK1/2-mediated pathway. However, the details therein are still far from completely understood and a quantitative description of the associated proteins in the biological context may provide more insights into this process. Following our previous attempts in the quantitative analysis of MDR mechanisms, liquid chromatography-tandem mass spectrometry (LC-MS/MS)-based targeted proteomics was continually employed here to describe ERK/Bcl-2-mediated anti-apoptosis. A targeted proteomics assay was developed and validated first for the simultaneous quantification of ERK1/2 and Bcl-2. In particular, ERK isoforms (i.e., ERK1 and ERK2) and their differential phosphorylated forms including isobaric ones were distinguished. Using this assay, differential protein levels and site-specific phosphorylation stoichiometry were observed in parental drug-sensitive MCF-7/WT cancer cells and drug-resistant MCF-7/ADR cancer cells and breast tissue samples from two groups of patients who were either suspected or diagnosed to have drug resistance. In addition, quantitative analysis of the time course of both ERK1/2 and Bcl-2 in doxorubicin (DOX)-treated MCF-7/WT cells confirmed these findings. Overall, we propose that targeted proteomics can be used generally to resolve more complex cellular events.

  9. Ovarian serous carcinoma: relationship of p53 and bcl-2 with tumor angiogenesis and VEGF expression.

    Science.gov (United States)

    Crasta, Julian A; Mishra, Suniti; Vallikad, Elizabeth

    2011-11-01

    The aim of the study was to assess the microvessel density (MVD) and vascular endothelial growth factor (VEGF) expression in ovarian serous carcinoma and to examine their relation with apoptosis.Paraffin-embedded specimens of 41 cases of ovarian serous carcinomas were evaluated by immunohistochemistry for VEGF, p53, and bcl-2 expression. MVD was assessed with CD31 staining. We investigated the association of tumor angiogenesis (MVD and VEGF) with clinicopathologic factors, p53 overexpression, and bcl-2 expression.There was a significant correlation between high MVD and suboptimal debulking and advanced stage disease. A significant negative correlation was expressed between bcl-2 and VEGF expression. In univariate analysis, only stage had a significant impact on disease-free survival.The results of this study suggest that higher degree of angiogenesis is associated with suboptimal debulking and advanced-stage disease. Expression of VEGF had negative association with VEGF expression.

  10. Nonsyndromic cleft lip with or without cleft palate: New BCL3 information

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    Amos, C.; Hecht, J.T. [Univ. of Texas Medical School, Houston, TX (United States); Gasser, D. [Univ. of Pennsylvania School of Medicine, Philadelphia, PA (United States)

    1996-09-01

    We did not previously provide LOD scores for linkage assuming heterogeneity, as suggested by Ott for the linkage analysis of cleft lip with or without cleft palate (CL/P) and BCL3, ApoC2, and D19S178 in the paper by Stein et al. The results from analysis using the HOMOG program, allowing for heterogeneity under the reduced penetrance model, gave a maximum LOD score of 1.85 for ApoC2, 0.41 for BCL3, 0.03 for D19S178, and 1.72 for multipoint analysis in the interval. For the affecteds-only model, the values are 1.96 for ApoC2, 0.41 for BCL3, 0.01 for D19S178, and 1.44 for the multipoint analysis. 8 refs.

  11. RBP2 Promotes Adult Acute Lymphoblastic Leukemia by Upregulating BCL2.

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    Xiaoming Wang

    Full Text Available Despite recent increases in the cure rate of acute lymphoblastic leukemia (ALL, adult ALL remains a high-risk disease that exhibits a high relapse rate. In this study, we found that the histone demethylase retinoblastoma binding protein-2 (RBP2 was overexpressed in both on-going and relapse cases of adult ALL, which revealed that RBP2 overexpression was not only involved in the pathogenesis of ALL but that its overexpression might also be related to relapse of the disease. RBP2 knockdown induced apoptosis and attenuated leukemic cell viability. Our results demonstrated that BCL2 is a novel target of RBP2 and supported the notion of RBP2 being a regulator of BCL2 expression via directly binding to its promoter. As the role of RBP2 in regulating apoptosis was confirmed, RBP2 overexpression and activation of BCL2 might play important roles in ALL development and progression.

  12. Bcl-6 directly represses the gene program of the glycolysis pathway

    Science.gov (United States)

    Oestreich, Kenneth J.; Read, Kaitlin A.; Gilbertson, Sarah E.; Hough, Kenneth P.; McDonald, Paul W.; Krishnamoorthy, Veena; Weinmann, Amy S.

    2014-01-01

    Despite our increasing knowledge of the molecular events that induce the glycolysis pathway in effector T cells, very little is known about the transcriptional mechanisms that dampen the glycolysis program in quiescent cell populations such as memory T cells. Here, we show that the transcription factor Bcl-6 directly repressed genes involved in the glycolysis pathway, including Slc2a1, Slc2a3, Pkm2 and Hk2, in TH1 cells exposed to low amounts of interleukin 2 (IL-2). Thus, Bcl-6 plays an opposing role to the IL-2-sensitive glycolytic transcriptional program that c-Myc and HIF-1α promote in effector T cells. Additionally, the Th1-lineage-specifying factor T-bet functionally antagonized the Bcl-6-dependent repression of genes in the glycolysis pathway, implicating the molecular balance between these two factors in metabolic gene program regulation. PMID:25194422

  13. Deregulated expression of A1, Bcl-2, Bcl-xL, and Mcl-1 antiapoptotic proteins and Bid, Bad, and Bax proapoptotic genes in polycythemia vera patients

    Directory of Open Access Journals (Sweden)

    Elainy Patricia Lino Gasparotto

    2011-12-01

    Full Text Available Apoptosis deregulation might have a role in the pathophysiology of polycythemia vera (PV. This study evaluated Bcl-2 molecule expression in CD34+ cells and leukocytes in 12 PV patients. Gene expression was investigated by real time PCR using SybrGreen Quantitect kit and protein expression was evaluated by western-blotting. JAK2 V617F mutation was detected according to Baxter et al (2005. CD34+ cells from PV patients presented higher levels of A1 and Mcl-1 expression (median: 22.6 and 5.2, respectively in comparison with controls (0.9 and 0.5, p=0.004 and p=0.020; while Bcl-2 and Bcl-xL expression decreased in PV patients (0.18 and 1.19 compared with controls (1.39 and 2.01, p=0.006 and p=0.020. CD34+ cells in PV patients showed an elevated Bid expression (14.4 in comparison with healthy subjects (1.0; p=0.002. Patients' leukocytes showed an A1 augmentation (7.41, p=0.001 and a reduced expression of Bax (0.19; p=0.040 and Bad (0.2; p=0.030. There was no correlation between JAK2 V617F allele burden and molecular expression. PV patients showed alterations in Bcl-2 members' expression, which may interfere with control of apoptotic machinery and contribute to disease pathogenesis.A desregulação da apoptose parece participar da fisiopatologia da policitemia vera (PV. Este estudo avaliou a expressão das moléculas da família Bcl-2 em células hematopoéticas CD34 + e leucócitos de 12 pacientes com PV. Foram realizados: a quantificação da expressão gênica por PCR em tempo real utilizando kit Sybrgreen Quantitect, avaliação da expressão de proteínas por western-blot e detecção da mutação JAK2 V617F segundo Baxter et al. (2005. Células CD34 + dos pacientes com PV apresentaram maior expressão de A1 e Mcl-1 (mediana: 22,6 e 5,2, respectivamente em comparação com controles (0,9 e 0,5, p = 0,004 e p = 0,020 e expressão de Bcl-2 e Bcl-xL diminuída nestes pacientes (0,18 e 1,19 em relação aos controles (1,39 e 2,01, p = 0,006 e p = 0

  14. Bcl-2 Allows Effector and Memory CD8+ T Cells To Tolerate Higher Expression of Bim

    Science.gov (United States)

    Kurtulus, Sema; Tripathi, Pulak; Moreno-Fernandez, Maria E.; Sholl, Allyson; Katz, Jonathan D.; Grimes, H. Leighton; Hildeman, David A.

    2014-01-01

    As acute infections resolve, most effector CD8+ T cells die, whereas some persist and become memory T cells. Recent work showed that subsets of effector CD8+ T cells, identified by reciprocal expression of killer cell lectin-like receptor G1 (KLRG1) and CD127, have different lifespans. Similar to previous reports, we found that effector CD8+ T cells reported to have a longer lifespan (i.e., KLRG1lowCD127high) have increased levels of Bcl-2 compared with their shorter-lived KLRG1highCD127low counterparts. Surprisingly, we found that these effector KLRG1lowCD127high CD8+ T cells also had increased levels of Bim compared with KLRG1highCD127low cells. Similar effects were observed in memory cells, in which CD8+ central memory T cells expressed higher levels of Bim and Bcl-2 than did CD8+ effector memory T cells. Using both pharmacologic and genetic approaches, we found that survival of both subsets of effector and memory CD8+ T cells required Bcl-2 to combat the proapoptotic activity of Bim. Interestingly, inhibition or absence of Bcl-2 led to significantly decreased expression of Bim in surviving effector and memory T cells. In addition, manipulation of Bcl-2 levels by IL-7 or IL-15 also affected expression of Bim in effector CD8+ T cells. Finally, we found that Bim levels were significantly increased in effector CD8+ T cells lacking Bax and Bak. Together, these data indicate that cells having the highest levels of Bim are selected against during contraction of the response and that Bcl-2 determines the level of Bim that effector and memory T cells can tolerate. PMID:21451108

  15. CASP10-BCL::Fold efficiently samples topologies of large proteins.

    Science.gov (United States)

    Heinze, Sten; Putnam, Daniel K; Fischer, Axel W; Kohlmann, Tim; Weiner, Brian E; Meiler, Jens

    2015-03-01

    During CASP10 in summer 2012, we tested BCL::Fold for prediction of free modeling (FM) and template-based modeling (TBM) targets. BCL::Fold assembles the tertiary structure of a protein from predicted secondary structure elements (SSEs) omitting more flexible loop regions early on. This approach enables the sampling of conformational space for larger proteins with more complex topologies. In preparation of CASP11, we analyzed the quality of CASP10 models throughout the prediction pipeline to understand BCL::Fold's ability to sample the native topology, identify native-like models by scoring and/or clustering approaches, and our ability to add loop regions and side chains to initial SSE-only models. The standout observation is that BCL::Fold sampled topologies with a GDT_TS score > 33% for 12 of 18 and with a topology score > 0.8 for 11 of 18 test cases de novo. Despite the sampling success of BCL::Fold, significant challenges still exist in clustering and loop generation stages of the pipeline. The clustering approach employed for model selection often failed to identify the most native-like assembly of SSEs for further refinement and submission. It was also observed that for some β-strand proteins model refinement failed as β-strands were not properly aligned to form hydrogen bonds removing otherwise accurate models from the pool. Further, BCL::Fold samples frequently non-natural topologies that require loop regions to pass through the center of the protein. © 2015 Wiley Periodicals, Inc.

  16. High expression of BCL-2 predicts favorable outcome in non-small cell lung cancer patients with non squamous histology

    Directory of Open Access Journals (Sweden)

    Detterbeck Frank

    2010-05-01

    Full Text Available Abstract Background Bcl-2 promotes cell survival by inhibiting adapters needed for the activation and cleavage of caspases thus blocking the proteolytic cascade that ultimately dismantles the cell. Bcl-2 has been investigated as a prognostic factor in non small cell lung cancer (NSCLC patients with conflicting results. Methods Here, we quantitatively assessed Bcl-2 expression in two large and independent cohorts to investigate the impact of Bcl-2 on survival. AQUA®, a fluorescent-based method for analysis of in situ protein expression, was used to measure Bcl-2 protein levels and classify tumors by Bcl-2 expression in a cohort of 180 NSCLC patients. An independent cohort of 354 NSCLC patients was used to validate Bcl-2 classification and evaluate outcome. Results Fifty % and 52% of the cases were classified as high expressers in training and validation cohorts respectively. Squamous cell carcinomas were more likely to be high expressers compared to adenocarcinomas (63% vs. 45%, p = 0.002; Bcl-2 was not associated with other clinical or pathological characteristics. Survival analysis showed that patients with high BCL-2 expression had a longer median survival compared to low expressers (22 vs. 17.5 months, log rank p = 0.014 especially in the subset of non-squamous tumors (25 vs. 13.8 months, log rank p = 0.04. Multivariate analysis revealed an independent lower risk for all patients with Bcl-2 expressing tumors (HR = 0.53, 95% CI 0.37-0.75, p = 0.0003 and for patients with non-squamous tumors (HR = 0.5, 95% CI 0.31-0.81, p = 0.005. Conclusions Bcl-2 expression defines a subgroup of patients with a favorable outcome and may be useful for prognostic stratification of NSCLC patients.

  17. The Bcl-2 family member BIM has multiple glaucoma-relevant functions in DBA/2J mice

    Science.gov (United States)

    Harder, Jeffrey M.; Fernandes, Kimberly A.; Libby, Richard T.

    2012-01-01

    Axonal insult induces retinal ganglion cell (RGC) death through a BAX-dependent process. The pro-apoptotic Bcl-2 family member BIM is known to induce BAX activation. BIM expression increased in RGCs after axonal injury and its induction was dependent on JUN. Partial and complete Bim deficiency delayed RGC death after mechanical optic nerve injury. However, in a mouse model of glaucoma, DBA/2J mice, Bim deficiency did not prevent RGC death in eyes with severe optic nerve degeneration. In a subset of DBA/2J mice, Bim deficiency altered disease progression resulting in less severe nerve damage. Bim deficient mice exhibited altered optic nerve head morphology and significantly lessened intraocular pressure elevation. Thus, a decrease in axonal degeneration in Bim deficient DBA/2J mice may not be caused by a direct role of Bim in RGCs. These data suggest that BIM has multiple roles in glaucoma pathophysiology, potentially affecting susceptibility to glaucoma through several mechanisms. PMID:22833783

  18. Novel Processes for Modular Integration of Silicon-Germanium MEMS with CMOS Electronics

    Science.gov (United States)

    2007-02-28

    40 3.1 Boron trichloride (BCl3) as the boron dopant gas ...........................................40 3.1.1 BCl3...is developing a copper-based MEMS process for RF switches and resonators [1.7]. Aluminum nitride (AlN) is being explored as the structural material...are described. Boron trichloride (BCl3) has been successfully developed as a better p-type dopant gas to replace diborane (B2H6); disilane (Si2H6

  19. Reversing multidrug resistance in Caco-2 by silencing MDR1, MRP1, MRP2, and BCL-2/BCL-xL using liposomal antisense oligonucleotides.

    Directory of Open Access Journals (Sweden)

    Yu-Li Lo

    Full Text Available Multidrug resistance (MDR is a major impediment to chemotherapy. In the present study, we designed antisense oligonucleotides (ASOs against MDR1, MDR-associated protein (MRP1, MRP2, and/or BCL-2/BCL-xL to reverse MDR transporters and induce apoptosis, respectively. The cationic liposomes (100 nm composed of N-[1-(2,3-dioleyloxypropyl]-n,n,n-trimethylammonium chloride and dioleoyl phosphotidylethanolamine core surrounded by a polyethylene glycol (PEG shell were prepared to carry ASOs and/or epirubicin, an antineoplastic agent. We aimed to simultaneously suppress efflux pumps, provoke apoptosis, and enhance the chemosensitivity of human colon adenocarcinoma Caco-2 cells to epirubicin. We evaluated encapsulation efficiency, particle size, cytotoxicity, intracellular accumulation, mRNA levels, cell cycle distribution, and caspase activity of these formulations. We found that PEGylated liposomal ASOs significantly reduced Caco-2 cell viability and thus intensified epirubicin-mediated apoptosis. These formulations also decreased the MDR1 promoter activity levels and enhanced the intracellular retention of epirubicin in Caco-2 cells. Epirubicin and ASOs in PEGylated liposomes remarkably decreased mRNA expression levels of human MDR1, MRP1, MRP2, and BCL-2. The combined treatments all significantly increased the mRNA expressions of p53 and BAX, and activity levels of caspase-3, -8, and -9. The formulation of epirubicin and ASOs targeting both pump resistance of MDR1, MRP1, and MRP2 and nonpump resistance of BCL-2/BCL-xL demonstrated more superior effect to all the other formulations used in this study. Our results provide a novel insight into the mechanisms by which PEGylated liposomal ASOs against both resistance types act as activators to epirubicin-induced apoptosis through suppressing MDR1, MRP1, and MRP2, as well as triggering intrinsic mitochondrial and extrinsic death receptor pathways. The complicated regulation of MDR highlights the necessity

  20. Association of BCL11A genetic variant (rs11886868 with severity in β-thalassaemia major & sickle cell anaemia

    Directory of Open Access Journals (Sweden)

    Sneha Dadheech

    2016-01-01

    Interpretation & conclusions: This study confirms that the T/C variant (rs11886868 of the BCL11A gene causing downregulation of BCL11A gene expression in adult erythroid precursors results in the induction of HbF and ameliorates the severity of β-thalassaemia as well as SCA.

  1. Hepatitis C virus positive diffuse large B-cell lymphomas have distinct molecular features and lack BCL2 translocations

    DEFF Research Database (Denmark)

    Visco, Carlo; Wang, Jinfen; Tisi, Maria Chiara

    2017-01-01

    for MYC, BCL2 and BCL6, TP53 mutations, and diagnostic specimens reviewed to exclude transformation from low-grade lymphoma. RESULTS: Compared to the HCV-negative controls, patients with HCV-positive de novo DLBCL had differential expression of genes that regulate innate immune response and modulate...

  2. [From dualism to multiplicity: seeing BCL-2 family proteins and cell death with new eyes].

    Science.gov (United States)

    Aouacheria, Abdel

    2015-01-01

    The concept of cell death has many links to the concept of death itself, defined as the opposite of life. Achievements obtained through research on apoptosis have apparently allowed us to transcend this Manichean view. Death is no longer outside, but rather inside living systems, as a constitutive force at work within the living matter. Whereas the death of cells can be positive and breed "creation" (e.g. during morphogenesis), its dysregulation can also cause or contribute to fatal diseases including cancer. It is tempting to apply this biological discourse to illuminate the relations between life and death, taken in general terms, but does this generalization actually hold? Is this discourse not essentially a metaphor? If cell death is considered as a vital aspect of various biological processes, then are we not faced with some vitalistic conception of death? Are there one or more meanings to the word "death"? Does the power to self-destruct act in opposition to other key features of living entities, or rather in juxtaposition to them? In this article, we first describe how the field of cell death has been developed on the basis of perceived and built dichotomies, mirroring the original opposition between life and death. We detail the limitations of the current paradigm of apoptosis regulation by BCL-2 family proteins, which nicely illustrate the problem of binary thinking in biology. Last, we try to show a way out of this dualistic matrix, by drawing on the notions of multiplicity, complexity, diversity, evolution and contingency. © Société de Biologie, 2016.

  3. Methoxychlor induces atresia by altering Bcl2 factors and inducing caspase activity in mouse ovarian antral follicles in vitro

    Science.gov (United States)

    Basavarajappa, Mallikarjuna S.; Karman, Bethany N.; Wang, Wei; Gupta, Rupesh K.; Flaws, Jodi A.

    2012-01-01

    Methoxychlor (MXC) is an organochlorine pesticide widely used in many countries against various species of insects that attack crops and domestic animals. MXC reduces fertility by increasing atresia (death) of antral follicles in vivo. MXC also induces atresia of antral follicles after 96 h in vitro. The current work tested the hypothesis that MXC induces morphological atresia at early time points (24 and 48 h) by altering pro-apoptotic (Bax, Bok, Casp3, and caspase activity) and anti-apoptotic (Bcl2 and Bcl-xL) factors in the follicles. The results indicate that at 24 h, MXC increased Bcl-xL and Bax mRNA levels and increased the ratio of Bax/Bcl2. At 48–96 h, MXC induced morphological atresia. At 24–96 h, MXC increased caspase activities. These data suggest that MXC may induce atresia by altering Bcl2 factors and inducing caspase activities in antral follicles. PMID:23000595

  4. Mutational analysis of Bax and Bcl-2 in childhood acute lymphoblastic leukaemia

    NARCIS (Netherlands)

    Salomons, G. S.; Buitenhuis, C. K.; Martínez Muñoz, C.; Verwijs-Jassen, M.; Behrendt, H.; Zsiros, J.; Smets, L. A.

    1998-01-01

    In childhood acute lymphoblastic leukaemia there are large interpatient variations in levels of the apoptosis-regulating proteins Bax and Bcl-2, but the molecular basis for this variation is unknown. Point-mutations in bax have been reported in cell lines derived from haematological malignancies.

  5. Bax/Bcl-2 expression ratio in prediction of response to breast cancer radiotherapy

    Directory of Open Access Journals (Sweden)

    Hosein Azimian

    2018-03-01

    Full Text Available Objective(s: Radiotherapy is one of the most effective modalities of cancer therapy, but clinical responses of individual patients varies considerably. To enhance treatment efficiency it is essential to implement an individual-based treatment. The aim of present study was to identify the mechanism of intrinsic apoptosis pathway on radiosensitivity and normal tissue complications caused by the radiotherapy. Materials and Methods: Peripheral blood mononuclear cells from ten breast cancer patients were exposed to 6MV X-rays to deliver 1 and 2 Gy. Expression levels of Bax, Bcl-2, and Bax/Bcl-2 ratio were examined by relative quantitative RT-PCR. All the patients received similar tangential irradiation of the whole breast and conventional fractionation. Skin dosimetry was done by GAFChromic EBT-3 film and clinical radiosensitivity was determined using the acute reactions to radiotherapy of the skin according to Radiation Therapy Oncology Group score. All statistical analyses were performed using GraphPad Prism, version 7.01. Results: In the in-vitro experiment, Bax and Bax/Bcl-2 ratios were significantly increased with 1 and 2 Gy doses (PP0.05 for all patients. Conclusion: Significant correlation between Bax/Bcl-2 ratio determined before radiation therapy and clinical response in the patients, can be used as a biomarker to identify radiosensitive individuals. However, further studies are required to validate radiation-induced apoptotic biomarkers.

  6. Expression of caspase-3, p53 and Bcl-2 in generalized aggressive periodontitis

    Directory of Open Access Journals (Sweden)

    Özdemir B Handan

    2006-06-01

    Full Text Available Abstract Background Apoptosis, or programmed cell death is a form of physiological cell death. It is increased or decreased in the presence of infection, inflammation or tissue remodelling. Previous studies suggest that apoptosis is involved in the pathogenesis of inflammatory periodontal disease. The aim of the present study was to investigate the clinical features and known indicators of apoptosis (p53, Bcl-2, Caspase-3 in patients with generalized aggressive periodontitis (GAP Methods Eight patients with GAP, who had sites with probing depths (PD > 5 mm, and 10 periodontally-healthy persons were included in the study. Clinical examinations and PD were performed, and the plaque index and gingival index were recorded. Gingival tissues biopsies were obtained from active site of each patient and from healthy individuals. The expression of caspase-3, Bcl-2, and p53 was evaluated by immunohistochemistry Results There were no significant differences between GAP and control group with respect to levels of caspase-3 and p53 expression (P > 0.05. Contrary, the frequency of grade 3 expression of Bcl-2 was higher in GAP group than the control group. Conclusion The higher frequency of Bcl-2 expression in GAP group indicates and delayed apoptosis can lead to increasing resident inflammatory cells in periodontal tissues and resulting in progressive periodontal destruction.

  7. Small Molecule Inhibitors of Bcl-2 Family Proteins for Pancreatic Cancer Therapy

    International Nuclear Information System (INIS)

    Masood, Ashiq; Azmi, Asfar S.; Mohammad, Ramzi M.

    2011-01-01

    Pancreatic cancer (PC) has a complex etiology and displays a wide range of cellular escape pathways that allow it to resist different treatment modalities. Crucial signaling molecules that function downstream of the survival pathways, particularly at points where several of these pathways crosstalk, provide valuable targets for the development of novel anti-cancer drugs. Bcl-2 family member proteins are anti-apoptotic molecules that are known to be overexpressed in most cancers including PC. The anti-apoptotic machinery has been linked to the observed resistance developed to chemotherapy and radiation and therefore is important from the targeted drug development point of view. Over the past ten years, our group has extensively studied a series of small molecule inhibitors of Bcl-2 against PC and provide solid preclinical platform for testing such novel drugs in the clinic. This review examines the efficacy, potency, and function of several small molecule inhibitor drugs targeted to the Bcl-2 family of proteins and their preclinical progress against PC. This article further focuses on compounds that have been studied the most and also discusses the anti-cancer potential of newer class of Bcl-2 drugs

  8. miR-127 regulates cell proliferation and senescence by targeting BCL6.

    Directory of Open Access Journals (Sweden)

    Jingwen Chen

    Full Text Available Cellular senescence occurs as a response to extracellular and intracellular stresses and contributes to aging and age-related pathologies. Emerging evidence suggests that cellular senescence also acts as a potent tumor suppression mechanism that prevents the oncogenic transformation of primary human cells. Recent reports have indicated that miRNAsact as key modulators of cellular senescence by targeting critical regulators of the senescence pathways. We previously reported that miR-127 is up-regulated in senescent fibroblasts. In this report, we identified miR-127 as a novel regulator of cellular senescence that directly targets BCL6. We further showed that miR-127 is down-regulated in breast cancer tissues and that this down-regulation is associated with up-regulation of BCL6. Over-expression of miR-127 or depletion of BCL6 inhibits breast cancer cell proliferation. Our data suggest that miR-127 may function as a tumor suppressor that modulates the oncogene BCL6.

  9. Genetic polymorphisms of Bcl-2 promoter in cancer susceptibility and prognosis: a meta-analysis.

    Science.gov (United States)

    Yao, Zhongqiang; Yang, Binhui; Liu, Zhongqiu; Li, Wei; He, Qihua; Peng, Xingchun

    2017-04-11

    Bcl-2 is critical for tumorigenesis. However, previous studies on the association of Bcl-2 promoter polymorphisms with predisposition to different cancer types are somewhat contradictory. Therefore, we performed this meta-analysis regarding the relationship between Bcl-2 promoter single nucleotide polymorphisms (SNPs) and cancer susceptibility and prognosis. Up to August 2016, 32 original publications were identified covering two Bcl-2 promoter SNPs (rs2279115 and rs1801018). Our results showed statistically significant association between rs2279115 and cancer susceptibility and prognosis in all four genetic models but not in rs1801018. Subgroups analysis indicated that rs2279115 was associated with a significantly higher risk of cancer susceptibility in Asia but not in Caucasian. Furthermore, rs2279115 was associated with a significantly higher risk in digestive system cancer and endocrine system cancer but not in breast cancer, respiratory cancer and hematopoietic cancer. Simultaneously, rs2279115 was correlated with a significantly higher risk of cancer prognosis in Asia but not in Caucasian. Considering these promising results, rs2279115 may be a tumor marker for cancertherapy in Asia. Sensitivity analysis show four gene model were stable, and no publication bias was observed in all four gene model. Large sample size, different ethnic population and different cancer type are warranted to validate this association.

  10. Xanthorrhizol induced DNA fragmentation in HepG2 cells involving Bcl-2 family proteins

    International Nuclear Information System (INIS)

    Tee, Thiam-Tsui; Cheah, Yew-Hoong; Meenakshii, Nallappan; Mohd Sharom, Mohd Yusof; Azimahtol Hawariah, Lope Pihie

    2012-01-01

    Highlights: ► We isolated xanthorrhizol, a sesquiterpenoid compound from Curcuma xanthorrhiza. ► Xanthorrhizol induced apoptosis in HepG2 cells as observed using SEM. ► Apoptosis in xanthorrhizol-treated HepG2 cells involved Bcl-2 family proteins. ► DNA fragmentation was observed in xanthorrhizol-treated HepG2 cells. ► DNA fragmentation maybe due to cleavage of PARP and DFF45/ICAD proteins. -- Abstract: Xanthorrhizol is a plant-derived pharmacologically active sesquiterpenoid compound isolated from Curcuma xanthorrhiza. Previously, we have reported that xanthorrhizol inhibited the proliferation of HepG2 human hepatoma cells by inducing apoptotic cell death via caspase activation. Here, we attempt to further elucidate the mode of action of xanthorrhizol. Apoptosis in xanthorrhizol-treated HepG2 cells as observed by scanning electron microscopy was accompanied by truncation of BID; reduction of both anti-apoptotic Bcl-2 and Bcl-X L expression; cleavage of PARP and DFF45/ICAD proteins and DNA fragmentation. Taken together, these results suggest xanthorrhizol as a potent antiproliferative agent on HepG2 cells by inducing apoptosis via Bcl-2 family members. Hence we proposed that xanthorrhizol could be used as an anti-liver cancer drug for future studies.

  11. Xanthorrhizol induced DNA fragmentation in HepG2 cells involving Bcl-2 family proteins

    Energy Technology Data Exchange (ETDEWEB)

    Tee, Thiam-Tsui, E-mail: thiamtsu@yahoo.com [School of Biosciences and Biotechnology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor (Malaysia); Cheah, Yew-Hoong [School of Biosciences and Biotechnology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor (Malaysia); Bioassay Unit, Herbal Medicine Research Center, Institute for Medical Research, Jalan Pahang, Kuala Lumpur (Malaysia); Meenakshii, Nallappan [Biology Department, Faculty of Science, Universiti Putra Malaysia, 43400 Serdang, Selangor (Malaysia); Mohd Sharom, Mohd Yusof; Azimahtol Hawariah, Lope Pihie [School of Biosciences and Biotechnology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor (Malaysia)

    2012-04-20

    Highlights: Black-Right-Pointing-Pointer We isolated xanthorrhizol, a sesquiterpenoid compound from Curcuma xanthorrhiza. Black-Right-Pointing-Pointer Xanthorrhizol induced apoptosis in HepG2 cells as observed using SEM. Black-Right-Pointing-Pointer Apoptosis in xanthorrhizol-treated HepG2 cells involved Bcl-2 family proteins. Black-Right-Pointing-Pointer DNA fragmentation was observed in xanthorrhizol-treated HepG2 cells. Black-Right-Pointing-Pointer DNA fragmentation maybe due to cleavage of PARP and DFF45/ICAD proteins. -- Abstract: Xanthorrhizol is a plant-derived pharmacologically active sesquiterpenoid compound isolated from Curcuma xanthorrhiza. Previously, we have reported that xanthorrhizol inhibited the proliferation of HepG2 human hepatoma cells by inducing apoptotic cell death via caspase activation. Here, we attempt to further elucidate the mode of action of xanthorrhizol. Apoptosis in xanthorrhizol-treated HepG2 cells as observed by scanning electron microscopy was accompanied by truncation of BID; reduction of both anti-apoptotic Bcl-2 and Bcl-X{sub L} expression; cleavage of PARP and DFF45/ICAD proteins and DNA fragmentation. Taken together, these results suggest xanthorrhizol as a potent antiproliferative agent on HepG2 cells by inducing apoptosis via Bcl-2 family members. Hence we proposed that xanthorrhizol could be used as an anti-liver cancer drug for future studies.

  12. Lymphocytes DNA Content, P53, C-Myc And Bcl-2 As Predictive ...

    African Journals Online (AJOL)

    Cell cycle parameters as well as apoptotic and tumor markers directly control cell growth. DNA ploidy and S phase fraction, apoptosis fraction in addition to apoptotic inducer (p53, c-myc) and antiapoptotic marker (Bcl-2) were investigated in childhood with acute lymphoblastic leukemia (ALL) leukemia as a predictive ...

  13. Alteration of Bax-to-Bcl-2 ratio modulates the anticancer activity of ...

    African Journals Online (AJOL)

    Real time quantitative RT-PCR and Western blot analyses of Bax, Bcl-2 and p53 exhibited aberrant expression profiles of these genes under various treatment conditions. Taken together, the data suggest that the crude methanolic extract of C. benghalensis contains bioactive compounds that may be beneficial in the ...

  14. Characterization of vNr-13, the first alphaherpesvirus gene of the bcl-2 family

    International Nuclear Information System (INIS)

    Aouacheria, Abdel; Banyai, Michelle; Rigal, Dominique; Schmidt, Carl J.; Gillet, Germain

    2003-01-01

    The Bcl-2 family, including antiapoptotic and proapoptotic members, plays key regulating roles in programmed cell death. We report the characterization of a new member of the bcl-2 family, encoded by herpesvirus of turkeys (HVT). The product of this gene shares 80% homology with Nr-13, an apoptosis inhibitor, which is overexpressed in avian cells transformed by the v-src oncogene. This new gene, that we propose to call vnr-13, is the first member of the bcl-2 family to be isolated among α-herpesviruses. Results from cells expressing the HVT-vnr-13 gene product show that the encoded protein inhibits apoptosis and also reduces the rate of cellular proliferation. Contrary to all bcl-2 homologues found in γ-herpesvirus, which are intronless, vnr-13 has the same organization as the cellular nr-13 gene. Hence, the HVT vnr-13 gene may have been acquired from a reverse transcriptase product of an unspliced precursor RNA, or via direct recombination with the host chromosomal DNA

  15. Kaiso is a key regulator of spleen germinal center formation by repressing Bcl6 expression in splenocytes

    Energy Technology Data Exchange (ETDEWEB)

    Koh, Dong-In; Yoon, Jae-Hyeon; Kim, Min-Kyeong; An, Haemin; Kim, Min-Young; Hur, Man-Wook, E-mail: mwhur2@yuhs.ac

    2013-12-13

    Highlights: •Knockout of Kaiso results in concordant high expression of Bcl6 and c-Myc in spleen. •Kaiso binds the Bcl6 promoter and represses Bcl6 transcription by recruiting NCoR. •Upregulated Bcl6 increases splenocyte proliferation and causes large diffused GC. •Cell cycle-inhibition genes such as Cdkn1b and Cdkn1a are repressed by Bcl6. -- Abstract: Kaiso was previously described as a methylated DNA-binding protein and a transcription repressor interacting with the corepressor protein complex NCoR. In the current study, we show that generation-3 Kaiso knockout mice show a phenotype of splenomegaly and large diffused germinal centers (GC). In the spleens of Kaiso knockout mice, Bcl6 (a transcriptional repressor that plays a critical role in GC development in spleen) and c-Myc were highly expressed, while the cell cycle arrest genes p27 (CDKN1B), p21 (CDKN1A) and Gadd45a were downregulated. Chromatin immunoprecipitation (ChIP) and transcription assays suggested that Kaiso represses Bcl6 expression, and in Kaiso knockout mice, derepressed Bcl6 increased cell proliferation by suppressing p27 (CDKN1B), p21 (CDKN1A) and Gadd45a, while upregulating the oncogene c-Myc. Further evidence for Kaiso regulation of splenomegaly was provided by B lymphocyte Ramos cells, in which ectopic KAISO repressed BCL6 and c-MYC expression, while concomitantly increasing the expression of the cell cycle arrestors p21, p27 and Gadd45a. In summary, derepressed Bcl6 expression may be responsible for increases in GC cell proliferation and splenomegaly of Kaiso knockout mice.

  16. The downregulation of Mcl-1 via USP9X inhibition sensitizes solid tumors to Bcl-xl inhibition

    International Nuclear Information System (INIS)

    Peddaboina, Chander; Smythe, W Roy; Cao, Xiaobo; Jupiter, Daniel; Fletcher, Steven; Yap, Jeremy L; Rai, Arun; Tobin, Richard P; Jiang, Weihua; Rascoe, Philip; Rogers, M Karen Newell

    2012-01-01

    It has been shown in many solid tumors that the overexpression of the pro-survival Bcl-2 family members Bcl-xL and Mcl-1 confers resistance to a variety of chemotherapeutic agents. Mcl-1 is a critical survival protein in a variety of cell lineages and is critically regulated via ubiquitination. The Mcl-1, Bcl-xL and USP9X expression patterns in human lung and colon adenocarcinomas were evaluated via immunohistochemistry. Interaction between USP9X and Mcl-1 was demonstrated by immunoprecipitation-western blotting. The protein expression profiles of Mcl-1, Bcl-xL and USP9X in multiple cancer cell lines were determined by western blotting. Annexin-V staining and cleaved PARP western blotting were used to assay for apoptosis. The cellular toxicities after various treatments were measured via the XTT assay. In our current analysis of colon and lung cancer samples, we demonstrate that Mcl-1 and Bcl-xL are overexpressed and also co-exist in many tumors and that the expression levels of both genes correlate with the clinical staging. The downregulation of Mcl-1 or Bcl-xL via RNAi was found to increase the sensitivity of the tumor cells to chemotherapy. Furthermore, our analyses revealed that USP9X expression correlates with that of Mcl-1 in human cancer tissue samples. We additionally found that the USP9X inhibitor WP1130 promotes Mcl-1 degradation and increases tumor cell sensitivity to chemotherapies. Moreover, the combination of WP1130 and ABT-737, a well-documented Bcl-xL inhibitor, demonstrated a chemotherapeutic synergy and promoted apoptosis in different tumor cells. Mcl-1, Bcl-xL and USP9X overexpression are tumor survival mechanisms protective against chemotherapy. USP9X inhibition increases tumor cell sensitivity to various chemotherapeutic agents including Bcl-2/Bcl-xL inhibitors

  17. Arsenite induces apoptosis in human mesenchymal stem cells by altering Bcl-2 family proteins and by activating intrinsic pathway

    International Nuclear Information System (INIS)

    Yadav, Santosh; Shi Yongli; Wang Feng; Wang He

    2010-01-01

    Purpose: Environmental exposure to arsenic is an important public health issue. The effects of arsenic on different tissues and organs have been intensively studied. However, the effects of arsenic on bone marrow mesenchymal stem cells (MSCs) have not been reported. This study is designed to investigate the cell death process caused by arsenite and its related underlying mechanisms on MSCs. The rationale is that absorbed arsenic in the blood circulation can reach to the bone marrow and may affect the cell survival of MSCs. Methods: MSCs of passage 1 were purchased from Tulane University, grown till 70% confluency level and plated according to the experimental requirements followed by treatment with arsenite at various concentrations and time points. Arsenite (iAs III ) induced cytotoxic effects were confirmed by cell viability and cell cycle analysis. For the presence of canonic apoptosis markers; DNA damage, exposure of intramembrane phosphotidylserine, protein and m-RNA expression levels were analyzed. Results: iAs III induced growth inhibition, G2-M arrest and apoptotic cell death in MSCs, the apoptosis induced by iAs III in the cultured MSCs was, via altering Bcl-2 family proteins and by involving intrinsic pathway. Conclusion: iAs III can induce apoptosis in bone marrow-derived MSCs via Bcl-2 family proteins, regulating intrinsic apoptotic pathway. Due to the multipotency of MSC, acting as progenitor cells for a variety of connective tissues including bone, adipose, cartilage and muscle, these effects of arsenic may be important in assessing the health risk of the arsenic compounds and understanding the mechanisms of arsenic-induced harmful effects.

  18. Correlation between apoptosis, proliferation and bcl-2 expression in malignant non-Hodgkin's lymphoma

    Science.gov (United States)

    Kiberu, S W; Pringle, J H; Sobolewski, S; Murphy, P; Lauder, I

    1996-01-01

    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. Images PMID:16696087

  19. Characterization of apoptosis and autophagy through Bcl-2 and Beclin-1 immunoexpression in gestational trophoblastic disease

    Directory of Open Access Journals (Sweden)

    Teresa Liliana Wargasetia

    2015-07-01

    Full Text Available Background: The pathogenesis of Gestational Trophoblastic Disease (GTD is not clearly known. Objective: In this study, immunoexpression of proteins Bcl-2 and Beclin-1 in trophoblastic lesions and normal trophoblastic tissue was conducted to study the mechanism of apoptotic and autophagic cell death that is expected to complete the study of GTD pathogenesis. Materials and Methods: Bcl-2 and Beclin-1 immunoexpression were studied on complete hydatidiform mole, partial hydatidiform mole, invasive mole, choriocarcinoma and normal placenta slides. Results: The average total scores of Bcl-2 immunoexpression had a decreasing value, starting from partial hydatidiform mole (3.09, complete hydatidiform mole (2.36, invasive mole (1.18 to choriocarcinoma (0 when compared to normal placenta (6. The results showed no significant difference in Beclin-1 immunoexpression total score between complete hydatidiform mole, partial hydatidiform mole and invasive mole, namely that the value of the average total score of Beclin-1 was low (2.27, 2.45 and 2.36, but on the contrary choriocarcinoma showed an increasing strong Beclin-1 expression with the average total score of 4.57. Conclusion: Bcl-2 expression decreases in line with the excessive proliferation of trophoblast cells in hydatidiform mole and leads to malignancy in invasive mole and choriocarcinoma. The decreased expression of Beclin-1 that leads to autophagy defects in complete hydatidiform mole, partial hydatidiform mole and invasive mole shows the role of autophagy as tumor suppressor, whereas strong Beclin-1 expression shows the survival role of autophagy in choriocarcinoma. The change of Bcl-2 activity as antiapoptosis and Beclin-1 as proautophagy plays a role in pathogenesis of GTD.

  20. Characterization of apoptosis and autophagy through Bcl-2 and Beclin-1 immunoexpression in gestational trophoblastic disease

    Science.gov (United States)

    Wargasetia, Teresa Liliana; Shahib, Nurhalim; Martaadisoebrata, Djamhoer; Dhianawaty, Diah; Hernowo, Bethy

    2015-01-01

    Background: The pathogenesis of Gestational Trophoblastic Disease (GTD) is not clearly known. Objective: In this study, immunoexpression of proteins Bcl-2 and Beclin-1 in trophoblastic lesions and normal trophoblastic tissue was conducted to study the mechanism of apoptotic and autophagic cell death that is expected to complete the study of GTD pathogenesis. Materials and Methods: Bcl-2 and Beclin-1 immunoexpression were studied on complete hydatidiform mole, partial hydatidiform mole, invasive mole, choriocarcinoma and normal placenta slides. Results: The average total scores of Bcl-2 immunoexpression had a decreasing value, starting from partial hydatidiform mole (3.09), complete hydatidiform mole (2.36), invasive mole (1.18) to choriocarcinoma (0) when compared to normal placenta (6). The results showed no significant difference in Beclin-1 immunoexpression total score between complete hydatidiform mole, partial hydatidiform mole and invasive mole, namely that the value of the average total score of Beclin-1 was low (2.27, 2.45 and 2.36), but on the contrary choriocarcinoma showed an increasing strong Beclin-1 expression with the average total score of 4.57. Conclusion: Bcl-2 expression decreases in line with the excessive proliferation of trophoblast cells in hydatidiform mole and leads to malignancy in invasive mole and choriocarcinoma. The decreased expression of Beclin-1 that leads to autophagy defects in complete hydatidiform mole, partial hydatidiform mole and invasive mole shows the role of autophagy as tumor suppressor, whereas strong Beclin-1 expression shows the survival role of autophagy in choriocarcinoma. The change of Bcl-2 activity as antiapoptosis and Beclin-1 as proautophagy plays a role in pathogenesis of GTD. PMID:26494988

  1. Effect of bcl-2 overexpression in mice on ovotoxicity caused by 4-vinylcyclohexene

    International Nuclear Information System (INIS)

    Flaws, Jodi A.; Marion, Samuel L.; Miller, Kimberly P.; Christian, Patricia J.; Babus, Janice K.; Hoyer, Patricia B.

    2006-01-01

    The occupational chemical 4-vinylcyclohexene (VCH) destroys small preantral ovarian follicles in mice following repeated daily dosing. The cell survival gene bcl-2 is thought to protect against follicular death during embryogenesis because primordial follicle numbers in newborn bcl-2 overexpressing (OE) mice are greater than in wild-type (WT) controls. Thus, this study was designed to determine if overexpression of bcl-2 protects against VCH-induced follicle loss during embryonic development. Pregnant bcl-2 OE or WT mice were dosed (p.o.) daily with VCH (500 mg/kg) or sesame oil (vehicle control) on days 8-18 of pregnancy. Ovaries were collected from moms and female pups on pup postnatal day (PND) 8. Nonpregnant OE and WT females were also treated with VCH (500 mg/kg p.o.) or vehicle and evaluated in the same manner. As previously reported, ovaries from PND8 OE female pups contained 50% more primordial follicles than WT pups (P < 0.05). Unlike WT pups, relative to vehicle controls, in utero exposure to VCH resulted in a reduction in primordial (25% of control), primary (38% of control), and secondary (33% of control) follicles in ovaries of OE pups (P < 0.05). VCH had no significant effect on follicle numbers in OE or WT moms. Conversely, in nonpregnant adults, VCH did not affect WT mice but caused loss of primordial (55% of control), primary (51% of control), and secondary (69% of control) follicles in OE mice (P < 0.05). These results demonstrate that bcl-2 overexpression does not protect against, but instead increases susceptibility to VCH-induced follicle loss in transplacentally exposed or in nonpregnant mice

  2. The small-molecule Bcl-2 inhibitor HA14-1 sensitizes cervical cancer cells, but not normal fibroblasts, to heavy-ion radiation

    International Nuclear Information System (INIS)

    Hamada, Nobuyuki; Kataoka, Keiko; Sora, Sakura; Hara, Takamitsu; Omura-Minamisawa, Motoko; Funayama, Tomoo; Sakashita, Tetsuya; Nakano, Takashi; Kobayashi, Yasuhiko

    2008-01-01

    This is the first study to demonstrate that the small-molecule Bcl-2 inhibitor HA14-1 renders human cervical cancer cells and their Bcl-2 overexpressing radioresistant counterparts, but not normal fibroblasts, more susceptible to heavy ions. Thus, Bcl-2 may be an attractive target for improving the efficacy of heavy-ion therapy

  3. Prometaphase arrest-dependent phosphorylation of Bcl-2 and Bim reduces the association of Bcl-2 with Bak or Bim, provoking Bak activation and mitochondrial apoptosis in nocodazole-treated Jurkat T cells.

    Science.gov (United States)

    Han, Cho Rong; Jun, Do Youn; Lee, Ji Young; Kim, Young Ho

    2014-01-01

    Treatment of Jurkat T cells with the microtubule-depolymerizing agent nocodazole (NOC) caused prometaphase arrest and apoptosis. NOC-induced mitochondrial apoptotic events including Bak activation, Δψm loss, cytochrome c release, and caspase cascade activation were blocked by Bcl-2 overexpression. However, mitotic arrest, Cdc25C activation, upregulation of cyclin B1 levels, Cdk1 activation, Bcl-2 phosphorylation at Thr-56 and Ser-70, and Bim phosphorylation were retained. The treatment of Jurkat T cells concomitantly with NOC and the G1/S-blocking agent hydroxyurea resulted in G1/S arrest and complete abrogation of all apoptotic events. The association of Bcl-2 with Bim or Bak declined after the prometaphase arrest-dependent phosphorylation of Bcl-2 and Bim, whereas the association of Bcl-2 with Bax remained relatively constant. Although Bax was redistributed from the cytosol to the mitochondria, resulting in an increase in the mitochondrial level of Bax following NOC treatment, the subcellular localization of Bcl-2, Bim, Bak and apoptosis-inducing factor was confined to the mitochondrial fraction irrespective of NOC treatment. Experiments using selective caspase inhibitors showed that mitochondria-dependent activation of caspase-9 and -3 was crucial for NOC-induced apoptosis. NOC-induced phosphorylation of Bcl-2 and Bim, Δψm loss, and mitochondria-dependent apoptotic events were significantly suppressed by a Cdk1 inhibitor roscovitine, but not by the JNK inhibitor SP600125 or the p38 MAPK inhibitor SB203580. These results show that the prometaphase arrest-dependent phosphorylation of Bcl-2 and Bim, which was mediated by Cdk1, could reduce the association of Bcl-2 with Bak or Bim to allow Bak activation and mitochondrial apoptotic events in Jurkat T cells exposed to NOC.

  4. p53-Dependent radiation-induced apoptosis in vivo: relationship to Bcl-2 and Bax expression

    International Nuclear Information System (INIS)

    Hasegawa, Masatoshi; Suzuki, Yoshiyuki; Furuta, Masaya; Yamakawa, Michitaka; Maebayashi, Katsuya; Hayakawa, Kayoko; Saito, Yoshihiro; Mitsuhashi, Norio; Niibe, Hideo

    1997-01-01

    Purpose: A close correlation between p53 protein expression and radiation-induced apoptosis has already been reported, however, Bcl-2 and Bax expression and the ratio of Bcl-2 to Bax have been also suggested to play an important role in the regulation of apoptotic cell death. In this study, we investigated the relationship between p53-dependent radiation-induced apoptosis and expression of Bcl-2 and Bax by using human tumors transplanted into nude mice. Materials and Methods: Three human tumors (an ependymoblastoma, a glioblastoma, and a small cell lung cancer) were subcutaneously transplanted into nude mice and irradiated with single doses of 1, 2, 5, or 10 Gy. The tumors were excised 1, 3, 6, 12, 24, and 48 hours after irradiation, fixed in 10% formalin for 24 hours, and embedded in paraffin. Slides were stained with hematoxylin and eosin for morphologic examination. Immunohistochemical studies were performed with mouse monoclonal antibodies to demonstrate p53, p21 (WAF-1), Bcl-2, and Bax expression. TdT-mediated dUTP-biotin nick-end labeling (TUNEL) and electron microscopic studies were performed to identify apoptosis, and PCR-SSCP analysis was used to evaluate p53 gene mutation. Results: All of the tumors showed only a few cells undergoing apoptosis before irradiation. Beginning several hours after irradiation, only the ependymoblastoma showed a large increase in the number of cells undergoing apoptosis, peaking at 6 hours after irradiation, and there was a clear dose-effect relationship. In contrast, the other tumors showed much less change following irradiation, and the dose-effect relationship was not as clear as in the ependymoblastoma. Immunohistochemically, the non-irradiated ependymoblastoma was negative for p53, p21, Bcl-2, and Bax. Following irradiation, however, many of the tumor cells became positive for p53 and p21, and a few cells became positive for bcl-2. In contrast, the glioblastoma and the small cell lung cancer were positive for p53 and Bcl-2

  5. Effect of polysaccharides from Angelica sinensis on Bcl-2 and Bax protein expression of irradiated liver cells

    International Nuclear Information System (INIS)

    Sun Yuanlin; Tang Jian; Gu Xiaohong; Li Deyuan

    2009-01-01

    Objective: To investigate the effect of polysaccharides from Angelica sinensis (ASP3) on Bcl-2 and Bax protein expression of irradiated liver cells from mice. Methods: Bcl-2 and Bax protein expression of liver cells in vitro exposed to 2.0 Gy rays were examined by using immunohistochemistry method. Results: The expression of apoptosis-accelerating protein Bax in the irradiation group was enhanced obviously (70.83%), while apoptosis inhibiting protein Bcl-2 tended to decline (55.60%), with the statistically significant difference (P <0.01) compared with that of the control. ASP3 pretreatment could regulate Bcl-2 and Bax protein expression of liver cells, inhibiting Bax protein expression(64.14/58.37%) and increasing Bcl-2 protein expression(59.21%/ 67.45%). The differences between the high dosage (100 mg/L of ASP3) and the irradiation group were statistically significant (P<0.05). Conclusions: ASP3 pretreatment could prohibit the apoptosis of radiation- damaged liver cells due to abnormal expression of Bcl-2 and Bax, and reduce the cell apoptosis by increasing Bcl-2/Bax protein expression so as to enhance the radiation endurance of liver cells. (authors)

  6. Inter- and intratumoral heterogeneity of BCL2 correlates with IgH expression and prognosis in follicular lymphoma

    International Nuclear Information System (INIS)

    Barreca, A; Martinengo, C; Annaratone, L; Righi, L; Chiappella, A; Ladetto, M; Demurtas, A; Chiusa, L; Stacchini, A; Crosetto, N; Oudenaarden, A van; Chiarle, R

    2014-01-01

    Most follicular lymphomas (FLs) are genetically defined by the t(14;18)(q32;q21) translocation that juxtaposes the BCL2 gene to the immunoglobulin heavy chain (IgH) 3' regulatory regions (IgH-3'RRs). Despite this recurrent translocation, FL cases are heterogeneous in terms of intratumoral clonal diversity for acquired mutations and variations in the tumor microenvironment. Here we describe an additional mechanism that contributes to inter- and intratumoral heterogeneity in FLs. By applying a novel single-molecule RNA fluorescence-based in situ hybridization (FISH) technique to detect mRNA molecules of BCL2 and IgH in single cells, we found marked heterogeneity in the number of BCL2 mRNA transcripts within individual lymphoma cells. Moreover, BCL2 mRNA molecules correlated with IgH mRNA molecules in individual cells both in t(14;18) lymphoma cell lines and in patient samples. Consistently, a strong correlation between BCL2 and IgH protein levels was found in a series of 205 primary FL cases by flow cytometry and immunohistochemistry. Inter- and intratumoral heterogeneity of BCL2 expression determined resistance to drugs commonly used in FL treatment and affected overall survival of FL patients. These data demonstrate that BCL2 and IgH expressions are heterogeneous and coregulated in t(14;18)-translocated cells, and determine the response to therapy in FL patients

  7. Nonsyndromic cleft lip with or without cleft palate: Evidence of linkage to BCL3 in 17 multigenerational families

    Energy Technology Data Exchange (ETDEWEB)

    Stein, J.; Hecht, T. [Univ. of Texas, Houston, TX (United States); Stal, S. [Texas Children`s Hospital, Houston, TX (United States)] [and others

    1995-08-01

    Nonsyndromic cleft lip with or without cleft palate (CL/P) is a common craniofacial developmental defect. Recent segregation analyses have suggested that major genes play a role in the etiology of CL/P. Linkage to 22 candidate genes was tested in 11 multigenerational families with CL/P, and 21 of these candidates were excluded. APOC2, 19q13.1, which is linked to the proto-oncogene BCL3, gave suggestive evidence for linkage to CL/P. The study was expanded to include a total of 39 multigenerational CL/P families. Linkage was tested in all families, using anonymous marker, D19S178, and intragenic markers in BCL3 and APOC2. Linkage was tested under two models, autosomal dominant with reduced penetrance and affecteds-only model. Both models showed evidence of heterogeneity, with 43% of families linked at zero recombination to BCL3 when marker data from BCL3 and APOC2 were included. A maximum multipoint LOD score of 7.00 at BCL3 was found among the 17 families that had posterior probabilities {ge}50% in favor of linkage. The transmission disequilibrium test provided additional evidence for linkage with the 3 allele of BCL3 more often transmitted to affected children. These results suggest that BCL3, or a nearby gene, plays a role in the etiology of CL/P in some families. 39 refs., 8 figs., 4 tabs.

  8. Cooperation of ETV6/RUNX1 and BCL2 enhances immunoglobulin production and accelerates glomerulonephritis in transgenic mice

    Science.gov (United States)

    Bauer, Eva; Schlederer, Michaela; Scheicher, Ruth; Horvath, Jaqueline; Aigner, Petra; Schiefer, Ana-Iris; Kain, Renate; Regele, Heinz; Hoermann, Gregor; Steiner, Günter; Kenner, Lukas; Sexl, Veronika; Villunger, Andreas; Moriggl, Richard; Stoiber, Dagmar

    2016-01-01

    The t(12;21) translocation generating the ETV6/RUNX1 fusion gene represents the most frequent chromosomal rearrangement in childhood leukemia. Presence of ETV6/RUNX1 alone is usually not sufficient for leukemia onset, and additional genetic alterations have to occur in ETV6/RUNX1-positive cells to cause transformation. We have previously generated an ETV6/RUNX1 transgenic mouse model where the expression of the fusion gene is restricted to CD19-positive B cells. Since BCL2 family members have been proposed to play a role in leukemogenesis, we investigated combined effects of ETV6/RUNX1 with exogenous expression of the antiapoptotic protein BCL2 by crossing ETV6/RUNX1 transgenic animals with Vav-BCL2 transgenic mice. Strikingly, co-expression of ETV6/RUNX1 and BCL2 resulted in significantly shorter disease latency in mice, indicating oncogene cooperativity. This was associated with faster development of follicular B cell lymphoma and exacerbated immune complex glomerulonephritis. ETV6/RUNX1-BCL2 double transgenic animals displayed increased B cell numbers and immunoglobulin titers compared to Vav-BCL2 transgenic mice. This led to pronounced deposition of immune complexes in glomeruli followed by accelerated development of immune complex glomerulonephritis. Thus, our study reveals a previously unrecognized synergism between ETV6/RUNX1 and BCL2 impacting on malignant disease and autoimmunity. PMID:26919255

  9. Cooperation of ETV6/RUNX1 and BCL2 enhances immunoglobulin production and accelerates glomerulonephritis in transgenic mice.

    Science.gov (United States)

    Bauer, Eva; Schlederer, Michaela; Scheicher, Ruth; Horvath, Jaqueline; Aigner, Petra; Schiefer, Ana-Iris; Kain, Renate; Regele, Heinz; Hoermann, Gregor; Steiner, Günter; Kenner, Lukas; Sexl, Veronika; Villunger, Andreas; Moriggl, Richard; Stoiber, Dagmar

    2016-03-15

    The t(12;21) translocation generating the ETV6/RUNX1 fusion gene represents the most frequent chromosomal rearrangement in childhood leukemia. Presence of ETV6/RUNX1 alone is usually not sufficient for leukemia onset, and additional genetic alterations have to occur in ETV6/RUNX1-positive cells to cause transformation. We have previously generated an ETV6/RUNX1 transgenic mouse model where the expression of the fusion gene is restricted to CD19-positive B cells. Since BCL2 family members have been proposed to play a role in leukemogenesis, we investigated combined effects of ETV6/RUNX1 with exogenous expression of the antiapoptotic protein BCL2 by crossing ETV6/RUNX1 transgenic animals with Vav-BCL2 transgenic mice. Strikingly, co-expression of ETV6/RUNX1 and BCL2 resulted in significantly shorter disease latency in mice, indicating oncogene cooperativity. This was associated with faster development of follicular B cell lymphoma and exacerbated immune complex glomerulonephritis. ETV6/RUNX1-BCL2 double transgenic animals displayed increased B cell numbers and immunoglobulin titers compared to Vav-BCL2 transgenic mice. This led to pronounced deposition of immune complexes in glomeruli followed by accelerated development of immune complex glomerulonephritis. Thus, our study reveals a previously unrecognized synergism between ETV6/RUNX1 and BCL2 impacting on malignant disease and autoimmunity.

  10. Diagnostic and prognostic value of BCL2 rearrangement in 53 patients with follicular lymphoma presenting as primary skin lesions.

    Science.gov (United States)

    Pham-Ledard, Anne; Cowppli-Bony, Anne; Doussau, Adélaïde; Prochazkova-Carlotti, Martina; Laharanne, Elodie; Jouary, Thomas; Belaud-Rotureau, Marc-Antoine; Vergier, Béatrice; Merlio, Jean-Philippe; Beylot-Barry, Marie

    2015-03-01

    To study the diagnostic value of BCL2 rearrangement in follicle center lymphoma (FCL) presenting as primary skin lesions, evaluate its prevalence and the prognostic value in primary cutaneous FCL (PCFCL), and assess prognostic factors in PCFCL. Fifty-three patients with a cutaneous presentation of FCL without a history of nodal lymphoma were selected retrospectively. Clinical and histologic data were collected together with staging and follow-up data. A fluorescence in situ hybridization (FISH) test for BCL2 split probes was performed on skin biopsy specimens. Initial staging procedures identified 47 PCFCLs and six cases of secondary skin involvement of FCL (SSIFCL). FISH detected seven cases carrying a BCL2 rearrangement: four (8.5%) of 47 PCFCLs and three (50%) of six SSIFCLs. These seven cases coexpressed BCL2 and CD10. In PCFCL, cutaneous relapse rate was 42.6%. A small/medium centrocytic cell population was associated with a higher probability of skin relapse in univariate (P = .008) and multivariate (P = .028) analysis, and BCL2 rearrangement detection was associated with secondary extracutaneous spreading (P = .05). We observed that BCL2 rearrangement in PCFCL is rare, associated with initial positivity of staging (diagnostic value) or with secondary extracutaneous spreading (prognostic value). In selected cases with BCL2-CD10 coexpression, FISH testing could detect patients with poor outcome and require closer monitoring. Copyright© by the American Society for Clinical Pathology.

  11. Helenalin bypasses Bcl-2-mediated cell death resistance by inhibiting NF-κB and promoting reactive oxygen species generation.

    Science.gov (United States)

    Hoffmann, Ruth; von Schwarzenberg, Karin; López-Antón, Nancy; Rudy, Anita; Wanner, Gerhard; Dirsch, Verena M; Vollmar, Angelika M

    2011-09-01

    Evasion of cell death by overexpression of anti-apoptotic proteins, such as Bcl-2, is commonly observed in cancer cells leading to a lack of response to chemotherapy. Hence, there is a need to find new chemotherapeutic agents that are able to overcome chemoresistance mediated by Bcl-2 and to understand their mechanisms of action. Helenalin, a sesquiterpene lactone (STL), induces cell death and abrogates clonal survival in a highly apoptosis-resistant Bcl-2 overexpressing Jurkat cell line as well as in two other Bcl-2 overexpressing solid tumor cell lines (mammary MCF-7; pancreatic L6.3pl). This effect is not achieved by directly affecting the mitochondria-protective function of Bcl-2 in the intrinsic pathway of apoptosis since Bcl-2 overexpressing Jurkat cells do not show cytochrome c release and dissipation of mitochondrial membrane potential upon helenalin treatment. Moreover, helenalin induces an atypical form of cell death with necrotic features in Bcl-2 overexpressing cells, neither activating classical mediators of apoptosis (caspases, AIF, Omi/HtrA2, Apaf/apoptosome) nor ER-stress mediators (BiP/GRP78 and CHOP/GADD153), nor autophagy pathways (LC3 conversion). In contrast, helenalin was found to inhibit NF-κB activation that was considerably increased in Bcl-2 overexpressing Jurkat cells and promotes cell survival. Moreover, we identified reactive oxygen species (ROS) and free intracellular iron as mediators of helenalin-induced cell death whereas activation of JNK and abrogation of Akt activity did not contribute to helenalin-elicited cell death. Our results highlight the NF-κB inhibitor helenalin as a promising chemotherapeutic agent to overcome Bcl-2-induced cell death resistance. Copyright © 2011. Published by Elsevier Inc.

  12. Bcl-2, Bax, and c-Fos expression correlates to RPE cell apoptosis induced by UV-light and daunorubicin

    DEFF Research Database (Denmark)

    Liang, Y G; Jorgensen, A G; Kaestel, C G

    2000-01-01

    PURPOSE. The aim of this study was to determine the role of Bcl-2, Bcl-X L, Bax, and c-Fos in regulation of apoptosis, induced by ultraviolet-light A (UV-A) and daunorubicin (DNR), in retinal pigment epithelium (RPE) cells grown on bovine extracellular matrix (ECM)-coated or uncoated plastic dishes......-A or DNR. This protection was found to be proportionally correlated to the anti-apoptotic protein Bcl-2 and inversely correlated to the expression of Bax. Furthermore a sustained induction and expression of c-Fos was found to correlate to a higher percentage of apoptotic cells of RPE cells grown on plastic...

  13. Dentatin Induces Apoptosis in Prostate Cancer Cells via Bcl-2, Bcl-xL, Survivin Downregulation, Caspase-9, -3/7 Activation, and NF-κB Inhibition

    Directory of Open Access Journals (Sweden)

    Ismail Adam Arbab

    2012-01-01

    Full Text Available This study was set to investigate antiproliferative potential of dentatin (a natural coumarin isolated from Clausena excavata Burm. F against prostate cancer and to delineate the underlying mechanism of action. Treatment with dentatin dose-dependently inhibited cell growth of PC-3 and LNCaP prostate cancer cell lines, whereas it showed less cytotoxic effects on normal prostate epithelial cell line (RWPE-1. The inhibitory effect of dentatin on prostate cancer cell growth was due to induction of apoptosis as evidenced by Annexin V staining and cell shrinkage. We found that dentatin-mediated accumulation of reactive oxygen species (ROS and downregulated expression levels of antiapoptotic molecules (Bcl-2, Bcl-xL, and Survivin, leading to disruption of mitochondrial membrane potential (MMP, cell membrane permeability, and release of cytochrome c from the mitochondria into the cytosol. These effects were associated with induction of caspase-9, -3/7 activities, and subsequent DNA fragmentation. In addition, we found that dentatin inhibited TNF-α-induced nuclear translocation of p65, suggesting dentatin as a potential NF-κB inhibitor. Thus, we suggest that dentatin may have therapeutic value in prostate cancer treatment worthy of further development.

  14. Limited prognostic value of tissue protein expression levels of BCl-2 in Danish ovarian cancer patients: from the Danish 'MALOVA' ovarian cancer study

    DEFF Research Database (Denmark)

    Høgdall, Estrid V S; Christensen, Lise Hanne; Kjaer, Susanne K

    2010-01-01

    The purpose of the study was to determine the expression of BCl-2 in epithelial ovarian tumors and to correlate expression levels with selected clinicopathologic parameters, time to progression and prognosis of the disease. Using tissue arrays (TA), we analyzed BCl-2 expression in tissues from 191.......19). A 30% cutoff value or a percentage scale showed that BCl-2 expression had no prognostic value, both in univariate and in multivariate survival analyses. No difference in time to progression was observed between patients with BCl-2-positive and negative tumors. These data suggest that BCl-2 expression...... may not be of important clinical value in the treatment of Danish OC patients....

  15. Autophagy Regulates the Post-Translational Cleavage of BCL-2 and Promotes Neuronal Survival

    Directory of Open Access Journals (Sweden)

    Laura Lossi

    2010-01-01

    Full Text Available B-cell lymphoma 2 protein (BCL-2 is one of the more widely investigated anti-apoptotic protein in mammals, and its levels are critical for protecting from programmed cell death. We report here that the cellular content of BCL-2 is regulated at post-translational level along the autophagy/lysosome pathways in organotypic cultures of post-natal mouse cerebellar cortex. Specifically this mechanism appears to be effective in the cerebellar granule cells (CGCs that are known to undergo massive programmed cell death (apoptosis during post-natal maturation. By the use of specific agonists/antagonist of calcium channels at the endoplasmic reticulum it was possible to understand the pivotal role of calcium release from intracellular stores in CGC neuroprotection. The more general significance of these findings is supported by a very recent study Niemann-Pick transgenic mice.

  16. BCL-2 and Bax Expression in Skin Flaps Treated with Finasteride or Azelaic Acid.

    Science.gov (United States)

    Ayatollahi, Seyyed Abdulmajid; Ajami, Marjan; Reyhanfard, Hamed; Asadi, Yasin; Nassiri-Kashani, Mansour; Rashighi Firoozabadi, Mehdi; Davoodi, Sayed Hossein; Habibi, Esmaeil; Pazoki-Toroudi, Hamidreza

    2012-01-01

    Despite all modern surgical techniques, skin flap that is considered as the main method in most reconstructive surgeries puts the skin tissue at danger of necrosis and apoptosis derived from ischemia. Therefore, finding a treatment for decreasing the apoptosis derived from flap ischemia will be useful in clinic. In present study, we evaluated the effect of azelaic acid 20% and finasteride on expression of BCL-2 and bax proteins after the skin flap surgery. For this purpose, 21 rats were entered in three groups including control, azelaic acid 20% and finasteride, all experienced skin flap surgery and then flap tissue was assessed for determining the expression of proteins in 5 slices prepared from each rat that were graded between - to +++ scales. Both azelaic acid and finasteride increased the expression of BCL-2 protein (p azelaic acid in preserving the flap after the ischemia reperfusion insult.

  17. Induction of Bcl-xL-specific cytotoxic T lymphocytes in mice

    DEFF Research Database (Denmark)

    Larsen, Helle Kiellberg; Andersen, M H; Wandall, H H

    2014-01-01

    -induced dedifferentiation. Identification of novel tumour-associated antigens that at the same time are essential for continued tumour cell survival is thus critical for the development of active cancer vaccinations. At the same time, identification of novel endogenous murine tumour antigens will help improve preclinical...... development of cancer immunotherapy. The anti-apoptotic protein Bcl-xL has been suggested to be such an essential tumour antigen, but the lack of well-defined murine epitopes have delayed preclinical studies of Bcl-xL-targeting cancer vaccines. Here, we report the identification of two novel murine tumour...... vaccination with an endogenous tumour antigen that can be combined with other cancer treatments....

  18. Bcl-2 protein level in blood of patients with acute myeloid leukaemia ...

    African Journals Online (AJOL)

    ةدﺎﺤﻟا ﺔﯿﻋﺎﺨﻨﻟا ﺎﯿﻤﯿﻛﻮﻠﻟا. ؛. ضاﺮﻋأ. ضﺮﻣ. ﻚﯿﺘﺳﻼﺒﺴﯾدﻮﻠﯿﻤﻟا. ؛. ﻦﯿﺗوﺮﺑ p53. Résumé. Nous avons recherché la relation entre la protéine bcl-2 dans le sang et l'existence d'une leucémie myéloïde aiguë (LMA), bcl-2 étant une protéine anti-apoptotique incriminée dans le cancer. Des échantillons sanguins ont été prélevés chez 28 patients ...

  19. SS-A/Ro52 promotes apoptosis by regulating Bcl-2 production

    International Nuclear Information System (INIS)

    Jauharoh, Siti Nur Aisyah; Saegusa, Jun; Sugimoto, Takeshi; Ardianto, Bambang; Kasagi, Shimpei; Sugiyama, Daisuke; Kurimoto, Chiyo; Tokuno, Osamu; Nakamachi, Yuji; Kumagai, Shunichi; Kawano, Seiji

    2012-01-01

    Highlights: ► Ro52 low HeLa cells are resistant to apoptosis upon various stimulations. ► Ro52 is upregulated by IFN-α, etoposide, or IFN-γ and anti-Fas Ab. ► Ro52-mediated apoptosis is independent of p53. ► Ro52 selectively regulates Bcl-2 expression. -- Abstract: SS-A/Ro52 (Ro52), an autoantigen in systemic autoimmune diseases such as systemic lupus erythematosus and Sjögren’s syndrome, has E3 ligase activity to ubiquitinate proteins that protect against viral infection. To investigate Ro52’s role during stress, we transiently knocked it down in HeLa cells by siRo52 transfection. We found that Ro52 low HeLa cells were significantly more resistant to apoptosis than wild-type HeLa cells when stimulated by H 2 O 2 - or diamide-induced oxidative stress, IFN-α, IFN-γ and anti-Fas antibody, etoposide, or γ-irradiation. Furthermore, Ro52-mediated apoptosis was not influenced by p53 protein level in HeLa cells. Depleting Ro52 in HeLa cells caused Bcl-2, but not other Bcl-2 family molecules, to be upregulated. Taken together, our data showed that Ro52 is a universal proapoptotic molecule, and that its proapoptotic effect does not depend on p53, but is exerted through negative regulation of the anti-apoptotic protein Bcl-2. These findings shed light on a new physiological role for Ro52 that is important to intracellular immunity.

  20. Butyrate down regulates BCL-XL and sensitizes human fibroblasts to radiation and chemotherapy induced apoptosis

    International Nuclear Information System (INIS)

    Chung, Diana H.; Ljungman, Mats; Zhang Fenfen; Chen Feng; McLaughlin, William P.

    1997-01-01

    Purpose/Objective: Butyrate is a short chain fatty acid that has been implicated in the induction of cell cycle arrest, cell differentiation and apoptosis. The purpose of this study was to determine if butyrate treatment sensitizes cells to radiation or chemotherapy induced apoptosis. Materials and Methods: Normal neonatal human diploid fibroblasts were used throughout this study. Apoptosis was scored and quantified using three different methods. First, cell morphology using propidium iodide and fluorescence microscopy was used to qualitatively determine apoptosis and to quantify the percentage of cells undergoing apoptosis. Second, apoptosis induced DNA degradation was scored by quantifying the amount of cells appearing in a sub-G1 peak using fixed and PI-stained cells and flow cytometry. Third, apoptosis-induced DNA degradation was examined by using an assay involving direct lysis of cells in the wells of agarose gels followed by conventional gel electrophoresis. Western blotting was used to quantify the cellular levels of the apoptosis regulators, Bcl-2, Bcl-XL and Bax. Results: Human diploid fibroblasts, which were resistant to radiation induced apoptosis, were found to undergo massive apoptosis when radiation was combined with butyrate treatment. Sensitization was obtained when butyrate was added before or after radiation although the combination of both pre and post-treatment was the most effective. Butyrate was also found to enhance UV light and cisplatin-induced apoptosis. These findings correlated with a reduction of the apoptosis antagonist Bcl-XL. Bcl-XL levels significantly dropped in a time and dose dependent manner. In addition, butyrate effectively blocked UV-induced accumulation of p53. Conclusion: Our results suggest that butyrate may be an attractive agent to use in combination with radiation or chemotherapy to lower the apoptotic threshold of tumor cells, regardless of the p53 status of the tumor cells

  1. Cyclic Marinopyrrole Derivatives as Disruptors of Mcl-1 and Bcl-xL Binding to Bim

    Directory of Open Access Journals (Sweden)

    Chunwei Cheng

    2014-03-01

    Full Text Available A series of novel cyclic marinopyrroles were designed and synthesized. Their activity to disrupt the binding of the pro-apoptotic protein, Bim, to the pro-survival proteins, Mcl-1 and Bcl-xL, was evaluated using ELISA assays. Both atropisomers of marinopyrrole A (1 show similar potency. A tetrabromo congener 9 is two-fold more potent than 1. Two novel cyclic marinopyrroles (3 and 4 are two- to seven-fold more potent than 1.

  2. Identification of a Novel Bcl10 Domain that Contributes to NK-kappaB Activation

    Science.gov (United States)

    2012-08-22

    clearance; granulocytes (e.g. neutrophils, basophils), which release endocytic vesicles containing chemicals such as hydrogen peroxide and histamine to...cluster (SMAC). At the SMAC, intracellular signaling molecules can more effectively be recruited to the activated TCR and transduce downstream...Intro-10), such as phosphorylation on Serine138 and its effect on Bcl10 in actin polymerization and T cell spreading [56]. Within the NF-ĸB signal

  3. Influence of p53 and bcl-2 on chemosensitivity in benign and malignant prostatic cell lines.

    Science.gov (United States)

    Serafin, Antonio M; Bohm, Lothar

    2005-01-01

    The administration of cancer chemotherapeutic agents results in an increase in the apoptotic cells in the tumor: therefore, it has been assumed that anticancer drugs exhibit their cytotoxic effects via apoptotic signaling pathways. Characteristics that confer sensitivity to drug-induced apoptosis are, a functional p53 protein and expression of the apoptosis-promoting protein, bax. The role of p53 and bax/bcl-2 in drug-induced apoptosis was assessed in six prostate cell lines, 1532T, 1535T, 1542T, 1542N, BPH-1 and LNCaP using TD(50) concentrations of etoposide, vinblastine and estramustine. Cell death was monitored morphologically by fluorescent microscopy, and by flow cytometry (Annexin-V assay). Apoptotic morphology was rather low and ranged from 0.1% to 12.1%, 3.0% to 6.0% and 0.1% to 8.5% for etoposide, estramustine and vinblastine, respectively. Annexin-V binding and flow cytometry indicated apoptotic propensities of 0% to 4%, 0% to 3% and 0% to 5%, respectively. The percentage of cells responding to drug-induced apoptosis was, on average, higher in the tumor cell lines than in the normal cell lines, but showed no correlation with p53 status. The percentage of cells showing necrosis, assessed by Annexin binding and Propidium Iodide permeability in aqueous medium, tended to be much higher, and was found to be at the level of 5% to 30%. Immunoblotting demonstrated that bax and bcl-2 proteins were expressed at a basal level in all cell lines, but did not increase after exposure to TD(50) doses of the three drugs. The ratio of bax and bcl-2, measured by laser scanning densitometry, was not altered by the drug-induced DNA damage. The results suggest that apoptosis is not a major mechanism of drug-induced cell death in prostate cell lines and appears to be independent of p53 status and bax/bcl-2 expression.

  4. Bcl-2 protein level in blood of patients with acute myeloid leukaemia ...

    African Journals Online (AJOL)

    De plus, la détermination des valeurs normales de la protéine bcl-2 pourrait être utile aux études portant sur diverses maladies où l'apoptose est soit augmentée, soit diminuée ou encore différée. ... diseases, such as Alzheimer disease and. Parkinson disease, are associated with the premature death of particular subsets of.

  5. SS-A/Ro52 promotes apoptosis by regulating Bcl-2 production

    Energy Technology Data Exchange (ETDEWEB)

    Jauharoh, Siti Nur Aisyah [Department of Clinical Pathology and Immunology, Kobe University Graduate School of Medicine, Hyogo 650-0017 (Japan); Faculty of Medicine and Health Science, Syarif Hidayatullah State Islamic University, Jakarta 15412 (Indonesia); Saegusa, Jun; Sugimoto, Takeshi [Department of Clinical Pathology and Immunology, Kobe University Graduate School of Medicine, Hyogo 650-0017 (Japan); Ardianto, Bambang [Department of Clinical Pathology and Immunology, Kobe University Graduate School of Medicine, Hyogo 650-0017 (Japan); Department of Child Health, Faculty of Medicine, Gadjah Mada University, Yogyakarta 55282 (Indonesia); Kasagi, Shimpei; Sugiyama, Daisuke; Kurimoto, Chiyo [Department of Clinical Pathology and Immunology, Kobe University Graduate School of Medicine, Hyogo 650-0017 (Japan); Tokuno, Osamu; Nakamachi, Yuji [Department of Laboratory Medicine, Kobe University Hospital, Hyogo 650-0017 (Japan); Kumagai, Shunichi [Department of Clinical Pathology and Immunology, Kobe University Graduate School of Medicine, Hyogo 650-0017 (Japan); Kawano, Seiji, E-mail: sjkawano@med.kobe-u.ac.jp [Department of Clinical Pathology and Immunology, Kobe University Graduate School of Medicine, Hyogo 650-0017 (Japan); Department of Laboratory Medicine, Kobe University Hospital, Hyogo 650-0017 (Japan)

    2012-01-06

    Highlights: Black-Right-Pointing-Pointer Ro52{sup low} HeLa cells are resistant to apoptosis upon various stimulations. Black-Right-Pointing-Pointer Ro52 is upregulated by IFN-{alpha}, etoposide, or IFN-{gamma} and anti-Fas Ab. Black-Right-Pointing-Pointer Ro52-mediated apoptosis is independent of p53. Black-Right-Pointing-Pointer Ro52 selectively regulates Bcl-2 expression. -- Abstract: SS-A/Ro52 (Ro52), an autoantigen in systemic autoimmune diseases such as systemic lupus erythematosus and Sjoegren's syndrome, has E3 ligase activity to ubiquitinate proteins that protect against viral infection. To investigate Ro52's role during stress, we transiently knocked it down in HeLa cells by siRo52 transfection. We found that Ro52{sup low} HeLa cells were significantly more resistant to apoptosis than wild-type HeLa cells when stimulated by H{sub 2}O{sub 2}- or diamide-induced oxidative stress, IFN-{alpha}, IFN-{gamma} and anti-Fas antibody, etoposide, or {gamma}-irradiation. Furthermore, Ro52-mediated apoptosis was not influenced by p53 protein level in HeLa cells. Depleting Ro52 in HeLa cells caused Bcl-2, but not other Bcl-2 family molecules, to be upregulated. Taken together, our data showed that Ro52 is a universal proapoptotic molecule, and that its proapoptotic effect does not depend on p53, but is exerted through negative regulation of the anti-apoptotic protein Bcl-2. These findings shed light on a new physiological role for Ro52 that is important to intracellular immunity.

  6. Expression of Bcl-2 Family Member Bid in Normal and Malignant Tissues

    Directory of Open Access Journals (Sweden)

    Maryla Krajewska

    2002-01-01

    Full Text Available Bid is the only known Bcl-2 family member that can function as an agonist of proapoptotic Bcl-2-related proteins such as Bax and Bak. Expression of the proapoptotic Bcl-2 family protein Bid was assessed by immunoblotting and immunohistochemical methods in normal murine and human tissues, and in several types of human cancers and tumor cell lines. Bid expression in normal tissues varied widely, with prominent Bid immunostaining occurring in several types of short-lived cells (e.g., germinal center B cells, peripheral blood granulocytes, differentiated keratinocytes and in apoptosissensitive cells (e.g., adult neurons. Analysis of Bid expression by immunostaining of 100 colon, 95 ovarian, and 254 prostate cancers, as well as 59 brain tumors and 50 lymphomas, revealed evidence of altered Bid regulation in sometypes of cancers. Correlations with clinical outcome data revealed association of higher levels of Bid with longer recurrence-free survival in men with locally advanced (T3 stage prostate cancer (P=0.04. Immunoblot analysis of Bid protein levels in the NCI's panel of 60 human tumor cell lines revealed a correlation between higher levels of Bid and sensitivity to ribonucleotide reductase (RR-inhibiting drugs (P<0.0005. Overexpression of Bid in a model tumor cell line by gene transfection resulted in increased sensitivity to apoptosis induction by a RR inhibitor. Taken together, these observations suggest a potential role for Bid in tumor responses to specific chemotherapeutic drugs, and lay a foundation for future investigations of this member of the Bcl-2 family in healthy and diseased tissues.

  7. Primary central nervous system diffuse large B-cell lymphoma shows an activated B-cell-like phenotype with co-expression of C-MYC, BCL-2, and BCL-6.

    Science.gov (United States)

    Li, Xiaomei; Huang, Ying; Bi, Chengfeng; Yuan, Ji; He, Hong; Zhang, Hong; Yu, QiuBo; Fu, Kai; Li, Dan

    2017-06-01

    Diffuse large B-cell lymphoma (DLBCL) is the most common non-Hodgkin lymphoma, whose main prognostic factor is closely related to germinal center B-cell-like subtype (GCB- DLBCL) or activated B-cell-like type (non-GCB-DLBCL). The most common type of primary central nervous system lymphoma is diffuse large B-cell type with poor prognosis and the reason is unclear. This study aims to stratify primary central nervous system diffuse large B-cell lymphoma (PCNS-DLBCL) according to the cell-of-origin (COO) and to investigate the multiple proteins expression of C-MYC, BCL-6, BCL-2, TP53, further to elucidate the reason why primary central nervous system diffuse large B-cell lymphoma possesses a poor clinical outcome as well. Nineteen cases of primary central nervous system DLBCL were stratified according to immunostaining algorithms of Hans, Choi and Meyer (Tally) and we investigated the multiple proteins expression of C-MYC, BCL-6, BCL-2, TP53. The Epstein-Barr virus and Borna disease virus infection were also detected. Among nineteen cases, most (15-17 cases) were assigned to the activated B-cell-like subtype, highly expression of C-MYC (15 cases, 78.9%), BCL-2 (10 cases, 52.6%), BCL-6 (15 cases, 78.9%). Unfortunately, two cases were positive for PD-L1 while PD-L2 was not expressed in any case. Two cases infected with BDV but no one infected with EBV. In conclusion, most primary central nervous system DLBCLs show an activated B-cell-like subtype characteristic and have multiple expressions of C-MYC, BCL-2, BCL-6 protein, these features might be significant factor to predict the outcome and guide treatment of PCNS-DLBCLs. Copyright © 2017 Elsevier GmbH. All rights reserved.

  8. Automated microinjection of recombinant BCL-X into mouse zygotes enhances embryo development.

    Directory of Open Access Journals (Sweden)

    Xinyu Liu

    Full Text Available Progression of fertilized mammalian oocytes through cleavage, blastocyst formation and implantation depends on successful implementation of the developmental program, which becomes established during oogenesis. The identification of ooplasmic factors, which are responsible for successful embryo development, is thus crucial in designing possible molecular therapies for infertility intervention. However, systematic evaluation of molecular targets has been hampered by the lack of techniques for efficient delivery of molecules into embryos. We have developed an automated robotic microinjection system for delivering cell impermeable compounds into preimplantation embryos with a high post-injection survival rate. In this paper, we report the performance of the system on microinjection of mouse embryos. Furthermore, using this system we provide the first evidence that recombinant BCL-XL (recBCL-XL protein is effective in preventing early embryo arrest imposed by suboptimal culture environment. We demonstrate that microinjection of recBCL-XL protein into early-stage embryos repairs mitochondrial bioenergetics, prevents reactive oxygen species (ROS accumulation, and enhances preimplantation embryo development. This approach may lead to a possible treatment option for patients with repeated in vitro fertilization (IVF failure due to poor embryo quality.

  9. Evaluation of the VITEK2 BCL card for identification of Bacillus species and other aerobic endosporeformers.

    Science.gov (United States)

    Halket, G; Dinsdale, A E; Logan, N A

    2010-01-01

    To evaluate the performance of the VITEK2 Bacillus identification card (BCL) for the identification of aerobic endospore-forming bacteria, using fresh isolates and reference strains. One hundred and nine industrial, environmental and clinical isolates were tested using the BCL card. The card contained 46 substrates for measuring carbon source utilization, enzymatic activities, inhibition by 6.5% NaCl and resistance to the antibiotics kanamycin, oleandomycin and polymyxin B. Identifications were made after 14 h incubation, using a database allowing identification of 42 species of the genera Aneurinibacillus, Bacillus, Brevibacillus, Geobacillus, Paenibacillus and Virgibacillus. The reference identities of all isolates were authenticated by phenotypic methods, with 16S rRNA gene sequencing used to resolve discrepancies. One hundred and one strains (93%) were identified correctly to species level, seven strains (6%) were incorrectly identified, and one strain (1%) remained unidentified. The VITEK2 BCL card provides a major advance in the reliable identification of Bacillus species and members of related genera.

  10. The oncoprotein BCL11A binds to orphan nuclear receptor TLX and potentiates its transrepressive function.

    Directory of Open Access Journals (Sweden)

    Sara B Estruch

    Full Text Available Nuclear orphan receptor TLX (NR2E1 functions primarily as a transcriptional repressor and its pivotal role in brain development, glioblastoma, mental retardation and retinopathologies make it an attractive drug target. TLX is expressed in the neural stem cells (NSCs of the subventricular zone and the hippocampus subgranular zone, regions with persistent neurogenesis in the adult brain, and functions as an essential regulator of NSCs maintenance and self-renewal. Little is known about the TLX social network of interactors and only few TLX coregulators are described. To identify and characterize novel TLX-binders and possible coregulators, we performed yeast-two-hybrid (Y2H screens of a human adult brain cDNA library using different TLX constructs as baits. Our screens identified multiple clones of Atrophin-1 (ATN1, a previously described TLX interactor. In addition, we identified an interaction with the oncoprotein and zinc finger transcription factor BCL11A (CTIP1/Evi9, a key player in the hematopoietic system and in major blood-related malignancies. This interaction was validated by expression and coimmunoprecipitation in human cells. BCL11A potentiated the transrepressive function of TLX in an in vitro reporter gene assay. Our work suggests that BCL11A is a novel TLX coregulator that might be involved in TLX-dependent gene regulation in the brain.

  11. The oncoprotein BCL11A binds to orphan nuclear receptor TLX and potentiates its transrepressive function.

    Science.gov (United States)

    Estruch, Sara B; Buzón, Víctor; Carbó, Laia R; Schorova, Lenka; Lüders, Jens; Estébanez-Perpiñá, Eva

    2012-01-01

    Nuclear orphan receptor TLX (NR2E1) functions primarily as a transcriptional repressor and its pivotal role in brain development, glioblastoma, mental retardation and retinopathologies make it an attractive drug target. TLX is expressed in the neural stem cells (NSCs) of the subventricular zone and the hippocampus subgranular zone, regions with persistent neurogenesis in the adult brain, and functions as an essential regulator of NSCs maintenance and self-renewal. Little is known about the TLX social network of interactors and only few TLX coregulators are described. To identify and characterize novel TLX-binders and possible coregulators, we performed yeast-two-hybrid (Y2H) screens of a human adult brain cDNA library using different TLX constructs as baits. Our screens identified multiple clones of Atrophin-1 (ATN1), a previously described TLX interactor. In addition, we identified an interaction with the oncoprotein and zinc finger transcription factor BCL11A (CTIP1/Evi9), a key player in the hematopoietic system and in major blood-related malignancies. This interaction was validated by expression and coimmunoprecipitation in human cells. BCL11A potentiated the transrepressive function of TLX in an in vitro reporter gene assay. Our work suggests that BCL11A is a novel TLX coregulator that might be involved in TLX-dependent gene regulation in the brain.

  12. Bcl11b: A New Piece to the Complex Puzzle of Amyotrophic Lateral Sclerosis Neuropathogenesis?

    Science.gov (United States)

    Lennon, Matthew J; Jones, Simon P; Lovelace, Michael D; Guillemin, Gilles J; Brew, Bruce J

    2016-02-01

    Amyotrophic lateral sclerosis (ALS) is an idiopathic, fatal, neurodegenerative disease of the human motor system. The pathogenesis of ALS is a topic of fascinating speculation and experimentation, with theories revolving around intracellular protein inclusions, mitochondrial structural issues, glutamate excitotoxicity and free radical formation. This review explores the rationale for the involvement of a novel protein, B-cell lymphoma/leukaemia 11b (Bcl11b) in ALS. Bcl11b is a multifunctional zinc finger protein transcription factor. It functions as both a transactivator and genetic suppressor, acting both directly, binding to promoter regions, and indirectly, binding to promoter-bound transcription factors. It has essential roles in the differentiation and growth of various cells in the central nervous system, immune system, integumentary system and cardiovascular system, to the extent that Bcl11b knockout mice are incompatible with extra-uterine life. It also has various roles in pathology including the suppression of latent retroviruses, thymic tumourigenesis and neurodegeneration. In particular its functions in neurodevelopment, viral latency and T-cell development suggest potential roles in ALS pathology.

  13. Multiplex PCR for the detection of BCL-1/IGH and BCL-2/IGH gene rearrangements--clinical validation in a prospective study of blood and bone marrow in 258 patients with or suspected of non-Hodgkin's lymphoma

    DEFF Research Database (Denmark)

    Nyvold, Charlotte G; Bendix, Knud; Brandsborg, Margrethe

    2007-01-01

    prospectively been evaluated. Eleven patients (4%) were found t(11;14)+ and 37 patients (14%) t(14;18)+. Comparing these results to standard diagnostic methods of PB and/or BM identified PCR+ samples that were normal by morphology (BCL-1/IGH: 1/11; BCL-2/IGH: 17/37). Equally important, patients who were......We have designed a multiplex PCR, which allows for fast and high throughput demonstration of the BCL-1/IGH and BCL-2/IGH fusion DNA observed primarily in mantle cell- and follicular non-Hodgkin's lymphoma (NHL). Blood (PB) and/or bone marrow (BM) from 258 patients suspected of NHL have...... not clonal in PB and/or BM by flow cytometry were identified as PCR+ (BCL-1/IGH: 3/11; BCL-2/IGH: 23/37). We conclude that this multiplex approach allows for easy and sensitive molecular determination of molecular lesions in NHL, which have diagnostic and prognostic importance. Udgivelsesdato: 2007-null...

  14. Bcl3-dependent stabilization of CtBP1 is crucial for the inhibition of apoptosis and tumor progression in breast cancer

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Hee June; Lee, Ji Min; Kim, Hyunkyung; Nam, Hye Jin; Shin, Hi-Jai R.; Kim, Dongha [Department of Biological Sciences, Creative Research Initiative Center for Chromatin Dynamics, Seoul National University, Seoul 151-742 (Korea, Republic of); Ko, Enyoung; Noh, Dong-Young [Department of Surgery and Cancer Research Institute, Seoul National University College of Medicine, Seoul 110-744 (Korea, Republic of); Kim, Keun Il [Department of Biological Sciences, Sookmyung Women' s University, Seoul 140-742 (Korea, Republic of); Kim, Jung Hwa [Department of Medical Sciences, Inha University, Incheon 402-751 (Korea, Republic of); Baek, Sung Hee, E-mail: sbaek@snu.ac.kr [Department of Biological Sciences, Creative Research Initiative Center for Chromatin Dynamics, Seoul National University, Seoul 151-742 (Korea, Republic of)

    2010-09-24

    Research highlights: {yields} CtBP1 as a new binding partner of Bcl3. {yields} Bcl3 stabilizes CtBP1 by inhibiting ubiquitination of CtBP1. {yields} Bcl3 antagonizes CtBP1-mediated apoptotic responses. {yields} Positive correlation between increased Bcl3 and CtBP1 protein levels in breast cancer tissues. -- Abstract: B-cell lymphoma 3 (Bcl3) is a proto-oncogene upregulated in a wide range of cancers, including breast cancer. Although Bcl3 is known to promote cell proliferation and inhibit apoptosis, the molecular mechanisms underlying the proto-oncogenic function of Bcl3 have not been completely elucidated. To gain insight into the oncogenic role of Bcl3, we applied a proteomic approach, which led to the identification of C-terminal binding protein 1 (CtBP1) as a binding partner of Bcl3. A PXDLS/R motif embedded in Bcl3 was found to mediate the interaction between Bcl3 and CtBP1, which caused the stabilization of CtBP1 by blocking proteasome-dependent degradation. Apoptotic stimuli-induced degradation of CtBP1 was significantly abolished by the upregulation of Bcl3, leading to the sustained repression of pro-apoptotic gene expression and subsequent inhibition of apoptosis. Intriguingly, a strong positive correlation between the protein levels of Bcl3 and CtBP1 was detected in breast cancer patient samples. Our study reveals a novel combinatorial role for Bcl3 and CtBP1, providing an explanation for the acquisition of resistance to apoptosis in cancer cells, which is a major requirement for cancer development.

  15. Acetylation of the proto-oncogene EVI1 abrogates Bcl-xL promoter binding and induces apoptosis.

    Directory of Open Access Journals (Sweden)

    Anjan Kumar Pradhan

    Full Text Available EVI1 (Ecotropic Viral Integration site I, which was originally identified as a myeloid transforming gene by means of retroviral insertional mutagenesis in mouse leukemia, encodes a nuclear DNA binding zinc finger protein. The presence of zinc fingers that are able to bind to specific sequences of DNA suggests that EVI1 is a transcriptional regulator; however, except a few, target genes of EVI1 are poorly functionally identified thus far. In this study we provide evidence that EVI1 directly induces the expression of Bcl-xL through the first set of zinc finger and thereby inhibits apoptosis. ChIP analysis showed that EVI1 binds to the Bcl-xL promoter in HT-29 cells, a colon carcinoma cell line, which expresses EVI1. The observation is also supported by the fact that EVI1 siRNA treated HT-29 cells, shows a down regulation of Bcl-xL expression and that over expression of EVI1 results in the induction of the Bcl-xL reporter construct. A set of EVI1 positive chronic myeloid leukemia (CML samples also showed higher Bcl-xL expression with respect to EVI1 negative samples. Interestingly, co-expression of EVI1 with wild type, but not with dominant-negative form of PCAF, abolishes the effect of EVI1 on Bcl-xL, indicating that acetylation of EVI1 abrogates its ability not only to bind Bcl-xL promoter but also alleviate Bcl-xL activity. Finally we have shown that EVI1 expression regulates apoptosis in HT-29 cells, which is abrogated when HT-29 cells are transfected with EVI1 siRNA or PCAF. The result for the first time shows a direct pathway by which EVI1 can protect cells from apoptosis and also demonstrates that the pathway can be reversed when EVI1 is acetylated.

  16. Role of reactive oxygen species and Bcl-2 family proteins in TNF-α-induced apoptosis of lymphocytes.

    Science.gov (United States)

    Ryazanceva, N V; Novickiy, V V; Zhukova, O B; Biktasova, A K; Chechina, O E; Sazonova, E V; Belkina, M V; Chasovskih, N Yu; Khaitova, Z K

    2010-08-01

    We studied the in vitro apoptosis-inducing effect of recombinant TNF-α (rTNF-α) on blood lymphocytes from healthy donors. rTNF-α-induced apoptosis was accompanied by an increase in the number of cells with low mitochondrial transmembrane potential, increased intracellular content of reactive oxygen species, reduced content of Bcl-2, Bcl-xL, and Bax proteins, and elevated Bad content. The molecular mechanisms of these changes are discussed.

  17. Involvement of Bax and Bcl-2 in Induction of Apoptosis by Essential Oils of Three Lebanese Salvia Species in Human Prostate Cancer Cells

    Directory of Open Access Journals (Sweden)

    Alessandra Russo

    2018-01-01

    Full Text Available Prostate cancer is one of the most common forms of cancer in men, and research to find more effective and less toxic drugs has become necessary. In the frame of our ongoing program on traditionally used Salvia species from the Mediterranean Area, here we report the biological activities of Salvia aurea, S. judaica and S. viscosa essential oils against human prostate cancer cells (DU-145. The cell viability was measured by 3(4,5-dimethyl-thiazol-2-yl2,5-diphenyl-tetrazolium bromide (MTT test and lactate dehydrogenase (LDH release was used to quantify necrosis cell death. Genomic DNA, caspase-3 activity, expression of cleaved caspase-9, B-cell lymphoma 2 (Bcl-2 and Bcl-2 associated X (Bax proteins were analyzed in order to study the apoptotic process. The role of reactive oxygen species in cell death was also investigated. We found that the three essential oils, containing caryophyllene oxide as a main constituent, are capable of reducing the growth of human prostate cancer cells, activating an apoptotic process and increasing reactive oxygen species generation. These results suggest it could be profitable to further investigate the effects of these essential oils for their possible use as anticancer agents in prostate cancer, alone or in combination with chemotherapy agents.

  18. Variant translocation of the bcl-2 gene to immunoglobulin λ light chain gene in chronic lymphocytic leukemia

    International Nuclear Information System (INIS)

    Adachi, M.; Cossman, J.; Longo, D.; Croce, C.M.; Tsujimoto, Y.

    1989-01-01

    The bcl-2 gene has been identified as a gene directly involved in the consistent chromosome translocation t(14;18), which is found in ∼ 90% of human follicular lymphoma cases, and is a prime candidate for the oncogene playing a crucial role in follicular lymphomagenesis. In this paper, the authors describe a case of chronic lymphocytic leukemia showing the juxtaposition of the bcl-2 gene on chromosome 18 to immunoglobulin λ light chain (Igλ) gene on chromosome 22 in a head-to-head configuration. Sequencing analysis of the joining site of the bcl-2 gene and Igλ gene has shown that the breakpoint is within the 5' flanking region of the bcl-2 gene and about 2.2 kilobases 5' to the joining segment of Igλ locus in a germ-line configuration. The extranucleotide, commonly appearing at the joining site of the t(14;18) translocation involving the IgH locus, is absent from the joining site of bcl-2 and Igλ. The lack of extranucleotide suggests that the juxtaposition of the bcl-2 and Igλ genes occurred during physiological rearrangement of the Igλ gene since it has been shown that the rearrangement of the Igλ locus is not accompanied by extranucleotides

  19. Born to be alive: a role for the BCL-2 family in melanoma tumor cell survival, apoptosis, and treatment

    Directory of Open Access Journals (Sweden)

    Rina Ashish Anvekar

    2011-10-01

    Full Text Available The global incidence of melanoma has dramatically increased during the recent decades, yet the advancement of primary and adjuvant therapies has not kept a similar pace. The development of melanoma is often centered on cellular signaling that hyper-activates survival pathways, while inducing a concomitant blockade to cell death. Aberrations in cell death signaling not only promote tumor survival and enhanced metastatic potential, but also create resistance to anti-tumor strategies. Chemotherapeutic agents target melanoma tumor cells by inducing a form of cell death called apoptosis, which is governed by the BCL-2 family of proteins. The BCL-2 family is comprised of anti-apoptotic proteins (e.g., BCL-2, BCL-xL, and MCL-1 and pro-apoptotic proteins (e.g., BAK, BAX, and BIM, and their coordinated regulation and function are essential for optimal responses to chemotherapeutics. Here we will discuss what is currently known about the mechanisms of BCL-2 family function with a focus on the signaling pathways that maintain melanoma tumor cell survival. Importantly, we will critically evaluate the literature regarding how chemotherapeutic strategies directly impact on BCL-2 family function and offer several suggestions for future regimens to target melanoma and enhance patient survival.

  20. BCL-3 attenuation of TNFA expression involves an incoherent feed-forward loop regulated by chromatin structure.

    Directory of Open Access Journals (Sweden)

    Thomas Walker

    Full Text Available Induction of genes is rarely an isolated event; more typically occurring as part of a web of parallel interactions, or motifs, which act to refine and control gene expression. Here, we define an Incoherent Feed-forward Loop motif in which TNFα-induced NF-κB signalling activates expression of the TNFA gene itself and also controls synthesis of the negative regulator BCL-3. While sharing a common inductive signal, the two genes have distinct temporal expression profiles. Notably, while the TNFA gene promoter is primed to respond immediately to activated NF-κB in the nucleus, induction of BCL3 expression only occurs after a time delay of about 1h. We show that this time delay is defined by remodelling of the BCL3 gene promoter, which is required to activate gene expression, and characterise the chromatin delayed induction of BCL3 expression using mathematical models. The models show how a delay in inhibitor production effectively uncouples the rate of response to inflammatory cues from the final magnitude of inhibition. Hence, within this regulatory motif, a delayed (incoherent feed-forward loop together with differential rates of TNFA (fast and BCL3 (slow mRNA turnover provide robust, pulsatile expression of TNFα . We propose that the structure of the BCL-3-dependent regulatory motif has a beneficial role in modulating expression dynamics and the inflammatory response while minimising the risk of pathological hyper-inflammation.

  1. Immunohistochemical study of p21 and Bcl-2 in leukoplakia, oral submucous fibrosis and oral squamous cell carcinoma.

    Science.gov (United States)

    Sutariya, Rakesh V; Manjunatha, Bhari Sharanesha

    2016-11-01

    Oral Squamous cell carcinoma (OSCC) results from genetic damage, leading to uncontrolled cell proliferation of damaged cells and the cell death. In the course of its progression, visible changes are taking place at the cellular level (atypical) and the resultant at the tissue level (epithelial dysplasia). The Aim of the present study was to evaluate and compare the expressions of intensity of p21 and Bcl-2 in Leukoplakia, oralsubmucous fibrosis (OSMF) and oral squamous cell carcinoma. Total 60 cases, 30 cases of oral squamous cell carcinoma, 15 cases of oral submucous fibrosis and 15 cases of Leukoplakia were evaluated immunohistochemically for p21 and Bcl-2 expression. p21 showed positive expression in 13 (86.67%) cases out of 15 cases of OSMF, 12 (80%) cases of leukoplakia out of 15 cases and 24 (80%) cases out of 30 cases of OSCC. The Bcl-2 expression was positive in 13 (86.67%) cases of OSMF, all cases of Leukoplakia and 25 (83.33%) cases of OSCC. No statistical significance was noted in the expression of p21 and Bcl-2 positive expression between OSMF, Leukoplakia and OSCC. Statistical analysis for comparison of intensity of p21 expression in different grades of OSCC showed no significance. Statistical significance difference was found between the expressions of Bcl-2 in moderately and poorly differentiated SCC. The intensity of p21 and Bcl-2 expressions in different grades of OSCC indicates a key role in progression of oral neoplasia.

  2. Bcl-2 and N-Myc Coexpression Increases IGF-IR and Features of Malignant Growth in Neuroblastoma Cell Lines

    Directory of Open Access Journals (Sweden)

    Rama Jasty

    2001-01-01

    Full Text Available The bcl-2 and c-myc oncogenes cooperate to transform multiple cell types. In the pediatric malignancy NB2, Bcl2 is highly expressed. In tumors with a poor prognosis, N-Myc, a protein homologous to c-Myc, is overexpressed as a result of gene amplification. The present study was designed to determine whether Bcl-2 cooperates with N-Myc to bestow a tumorigenic phenotype to neuroblastoma (NB cells. NB cell lines that at baseline express neither Bcl-2 nor N-Myc were stably transfected to express these gene products. In this model, we found Bcl-2 rescues N-Myc-expressing cells from apoptosis induced by serum withdrawal. Coexpression of Bcl-2 and N-Myc supports growth in low serum conditions and anchorage-independent growth in soft agar. Similarly, in vivo tumorigenic and angiogenic activity was dependent on coexpression. Our data further suggests that the mechanism underlying these changes involves the receptor for insulin growth factor type I (IGF-IR.

  3. Radiation-induced apoptosis in human myeloma cell line increases BCL-2/BAX dimer formation and does not result in BAX/BAX homodimerization.

    Science.gov (United States)

    Filippovich, I V; Sorokina, N I; Lisbona, A; Chérel, M; Chatal, J F

    2001-06-01

    A popular model of BCL-2 and BAX involvement in apoptosis suggests that upon apoptosis induction cytosolic BAX translocates to the mitochondria, where it displays the pro-apoptotic function, which involves its homodimerization. BCL-2 exerts anti-apoptotic function by forming heterodimers with BAX, thus neutralizing the pro-apoptotic activity of the latter. We have shown that irradiation of the human myeloma cell line RPMI-8226 induced apoptosis as determined by DNA degradation, cytochrome c release into cytoplasm and BCL-2 caspase-mediated cleavage. BCL-2 protein was present only in the membrane fraction, whereas BAX was found both in cytosol and membranes isolated from non-irradiated cells. Radiation induced moderate redistribution of BAX from cytosol to membranes with a concomitant increase in BCL-2/BAX heterodimer formation. Rapid and transient BCL-2 phosphorylation in membrane fractions of irradiated cells did not affect BCL-2/BAX heterodimerization. We failed to detect any BAX/BAX homodimers in apoptotic cells. Our findings show that in irradiated RPMI-8226 cells the formation of BCL-2/BAX heterodimers correlates with apoptosis. We conclude that BCL-2/BAX heterodimers are negative regulators of death protection, and our data agree with those who propose that BCL-2 does not require BAX to exert its survival function. Copyright 2001 Wiley-Liss, Inc.

  4. The role of the expression of bcl-2, p53 gene in tamoxifen-induced apoptosis of breast cancer cells and its relationship with hormone receptor status

    International Nuclear Information System (INIS)

    Noh, Woo Chul; Ham, Yong Ho

    1998-01-01

    To investigate the relationship of bcl-2, p53, ER and tamoxifen-induced apoptosis of breast cancer cells, MCF-7 (ER+/bcl-2+/p53-) and MB MDA 468 (ER-/bcl-2-/p53+) cell line were cultured in estrogen-free condition. E2(10'-'9M) and tamoxifen (10'-'5M) were added to the media. The changes of bcl-2 and mutant p53 protein were checked by Western blot and apoptosis were measured by flowcytometry. In MCF-7 cells, we found that treatment with tamoxifen resulted in a decrease in bcl-2 protein level, but produced no change in mutant p53. In MB MDA 468 cell however, there were no changes of bcl-2 and mutant p53 protein level when E2 or tamoxifen were added. Apoptotic cells increased with time-dependent pattern when tamoxifen was added to MCF-7 cells. According to these result, ER+/blc-2+/mutant p53- cells, when treated with tamoxifen, were converted into bcl-2/mutant p53- cells which were more prone to apoptosis than bcl-2-/mutant p53+ cells. The paradoxical correlation of bcl-2 and ER which had been observed in clinical studies might be explained with this results and bcl-2 protein seems to be one of important factors that can predict the effect of hormone therapy. (author). 26 refs., 5 figs

  5. The Mutant KRAS Gene Up-regulates BCL-XL Protein via STAT3 to Confer Apoptosis Resistance That Is Reversed by BIM Protein Induction and BCL-XL Antagonism.

    Science.gov (United States)

    Zaanan, Aziz; Okamoto, Koichi; Kawakami, Hisato; Khazaie, Khashayarsha; Huang, Shengbing; Sinicrope, Frank A

    2015-09-25

    In colorectal cancers with oncogenic GTPase Kras (KRAS) mutations, inhibition of downstream MEK/ERK signaling has shown limited efficacy, in part because of failure to induce a robust apoptotic response. We studied the mechanism of apoptosis resistance in mutant KRAS cells and sought to enhance the efficacy of a KRAS-specific MEK/ERK inhibitor, GDC-0623. GDC-0623 was shown to potently up-regulate BIM expression to a greater extent versus other MEK inhibitors in isogenic KRAS HCT116 and mutant KRAS SW620 colon cancer cells. ERK silencing enhanced BIM up-regulation by GDC-0623 that was due to its loss of phosphorylation at Ser(69), confirmed by a BIM-EL phosphorylation-defective mutant (S69G) that increased protein stability and blocked BIM induction. Despite BIM and BIK induction, the isogenic KRAS mutant versus wild-type cells remained resistant to GDC-0623-induced apoptosis, in part because of up-regulation of BCL-XL. KRAS knockdown by a doxycycline-inducible shRNA attenuated BCL-XL expression. BCL-XL knockdown sensitized KRAS mutant cells to GDC-0623-mediated apoptosis, as did the BH3 mimetic ABT-263. GDC-0623 plus ABT-263 induced a synergistic apoptosis by a mechanism that includes release of BIM from its sequestration by BCL-XL. Furthermore, mutant KRAS activated p-STAT3 (Tyr(705)) in the absence of IL-6 secretion, and STAT3 knockdown reduced BCL-XL mRNA and protein expression. These data suggest that BCL-XL up-regulation by STAT3 contributes to mutant KRAS-mediated apoptosis resistance. Such resistance can be overcome by potent BIM induction and concurrent BCL-XL antagonism to enable a synergistic apoptotic response. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

  6. Real world data on young patients with high-risk diffuse large B-cell lymphoma treated with R-CHOP or R-CHOEP - MYC, BCL2 and BCL6 as prognostic biomarkers.

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    Mette Ølgod Pedersen

    Full Text Available Double expression of MYC and BCL2 proteins (DE and double-hit MYC+BCL2/BCL6 translocations (DH were established as important biomarkers in patients with diffuse large B-cell lymphoma (DLBCL by the 2016 revision of the World Health Organization classification of lymphoid neoplasms. Whether this applies to the subgroup of young patients with high risk DLBCL is not known. We previously found that in a uniform retrospective population-based cohort of patients aged 18-60 years with high-risk DLBCL, the addition of etoposide to R-CHOP chemotherapy (R-CHOEP resulted in improved survival mainly in patients with germinal center B-cell like (GCB immunophenotype. The aim of this study was to investigate the prognostic and predictive value of DE and DH in this patient cohort.Data on all young Danish patients diagnosed with de novo high-risk DLBCL 2004-2008 and treated with R-CHOP or R-CHOEP were obtained from the Danish Lymphoma database (n = 159. Tumor samples were available from 103 patients. MYC and BCL2 proteins were analyzed with quantitative immunohistochemistry (IHC using different cut off values. MYC-, BCL2- and BCL6-translocations were examined with fluorescent in situ hybridization (FISH.DE with MYC>75% and BCL2>85% was an independent negative prognostic marker of progression free survival (PFS in patients treated with R-CHOP but not R-CHOEP (p<0.001, also after exclusion of patients with DH. A predictive effect of DE for response (PFS to R-CHOEP vs. R-CHOP was almost significant (p = 0.07. DH was not prognostic in this patient cohort.In young patients with high-risk DLBCL, treatment with R-CHOEP may overcome the negative prognostic impact of DE observed in patients treated with R-CHOP.

  7. LncRNA TUG1 sponges microRNA-9 to promote neurons apoptosis by up-regulated Bcl2l11 under ischemia.

    Science.gov (United States)

    Chen, Shengcai; Wang, Mengdie; Yang, Hang; Mao, Ling; He, Quanwei; Jin, Huijuan; Ye, Zi-Ming; Luo, Xue-Ying; Xia, Yuan-Peng; Hu, Bo

    2017-03-25

    Emerging studies have illustrated that LncRNAs TUG1 play critical roles in multiple biologic processes. However, the LncRNA TUG1 expression and function in ischemic stroke have not been reported yet. In this study, we found that LncRNA TUG1 expression was significantly up-regulated in brain ischemic penumbra from rat middle carotid artery occlusion (MCAO) model, while similar results were also observed in cultured neurons under oxygen-glucose deprivation (OGD) insult. Knockdown of TUG1 decreased the ratio of apoptotic cells and promoted cells survival in vitro, which may be regulated by the elevated miRNA-9 expression and decreased Bcl2l11 protein. Furthermore, TUG1 could directly interact with miR-9 and down-regulating miR-9 could efficiently reverse the function of TUG1 on the Bcl2l11 expression. In summary, our result sheds light on the role of LncRNA TUG1 as a miRNA sponge for ischemic stroke, possibly providing a new therapeutic target in stroke. Copyright © 2017 Elsevier Inc. All rights reserved.

  8. Opposite role of Bax and BCL-2 in the anti-tumoral responses of the immune system

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    Bougras Gwenola

    2004-08-01

    Full Text Available Abstract Background The relative role of anti apoptotic (i.e. Bcl-2 or pro-apoptotic (e.g. Bax proteins in tumor progression is still not completely understood. Methods The rat glioma cell line A15A5 was stably transfected with human Bcl-2 and Bax transgenes and the viability of theses cell lines was analyzed in vitro and in vivo. Results In vitro, the transfected cell lines (huBax A15A5 and huBcl-2 A15A5 exhibited different sensitivities toward apoptotic stimuli. huBax A15A5 cells were more sensitive and huBcl-2 A15A5 cells more resistant to apoptosis than mock-transfected A15A5 cells (pCMV A15A5. However, in vivo, in syngenic rat BDIX, these cell lines behaved differently, as no tumor growth was observed with huBax A15A5 cells while huBcl-2 A15A5 cells formed large tumors. The immune system appeared to be involved in the rejection of huBax A15A5 cells since i huBax A15A5 cells were tumorogenic in nude mice, ii an accumulation of CD8+ T-lymphocytes was observed at the site of injection of huBax A15A5 cells and iii BDIX rats, which had received huBax A15A5 cells developed an immune protection against pCMV A15A5 and huBcl-2 A15A5 cells. Conclusions We show that the expression of Bax and Bcl-2 controls the sensitivity of the cancer cells toward the immune system. This sensitization is most likely to be due to an increase in immune induced cell death and/or the amplification of an anti tumour immune response

  9. Inhibition of Bcl-2 potentiates AZD-2014-induced anti-head and neck squamous cell carcinoma cell activity

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    Li, Yi; Cui, Jiang-Tao, E-mail: cuijingtaopaper@126.com

    2016-09-02

    Mammalian target of rapamycin (mTOR) is a therapeutic target for head and neck squamous cell carcinoma (HNSCC). Here, we evaluated the activity of AZD-2014, a potent mTOR complex 1/2 (mTORC1/2) dual inhibitor, against HNSCC cells. We showed that AZD-2014 blocked mTORC1/2 activation in established and primary human HNSCC cells, where it was anti-proliferative and pro-apoptotic. Yet, AZD-2014 was non-cytotoxic to the human oral epithelial cells with low basal mTORC1/2 activation. In an effect to identify possible AZD-2014 resistance factors, we showed that the anti-apoptosis protein Bcl-2 was upregulated in AZD-2014-resistant SQ20B HNSCC cells. Inhibition of Bcl-2 by ABT-737 (a known Bcl-2 inhibitor) or Bcl-2 shRNA dramatically potentiated AZD-2014 lethality against HNSCC cells. On the other hand, exogenous overexpression of Bcl-2 largely attenuated AZD-2014’s activity against HNSCC cells. For the in vivo studies, we showed that oral gavage of AZD-2014 suppressed SQ20B xenograft growth in severe combined immunodeficient (SCID) mice. It also significantly improved mice survival. Importantly, AZD-2014’s anti-HNSCC activity in vivo was potentiated with co-administration of ABT-737. The preclinical results of this study suggest that AZD-2014 could be further tested as a valuable anti-HNSCC agent, either alone or in combination with Bcl-2 inhibitors. - Highlights: • AZD-2014 blocks mTORC1/2 activation in HNSCC cells. • AZD-2014 suppresses HNSCC cell proliferation. • AZD-2014 activates caspase-3 and apoptosis in HNSCC cells. • Bcl-2 is the key resistance factor of AZD-2014 in HNSCC cells. • ABT-737 sensitizes AZD-2014-induced anti-HNSCC activity in vivo.

  10. Inhibition of Bcl-2 potentiates AZD-2014-induced anti-head and neck squamous cell carcinoma cell activity

    International Nuclear Information System (INIS)

    Li, Yi; Cui, Jiang-Tao

    2016-01-01

    Mammalian target of rapamycin (mTOR) is a therapeutic target for head and neck squamous cell carcinoma (HNSCC). Here, we evaluated the activity of AZD-2014, a potent mTOR complex 1/2 (mTORC1/2) dual inhibitor, against HNSCC cells. We showed that AZD-2014 blocked mTORC1/2 activation in established and primary human HNSCC cells, where it was anti-proliferative and pro-apoptotic. Yet, AZD-2014 was non-cytotoxic to the human oral epithelial cells with low basal mTORC1/2 activation. In an effect to identify possible AZD-2014 resistance factors, we showed that the anti-apoptosis protein Bcl-2 was upregulated in AZD-2014-resistant SQ20B HNSCC cells. Inhibition of Bcl-2 by ABT-737 (a known Bcl-2 inhibitor) or Bcl-2 shRNA dramatically potentiated AZD-2014 lethality against HNSCC cells. On the other hand, exogenous overexpression of Bcl-2 largely attenuated AZD-2014’s activity against HNSCC cells. For the in vivo studies, we showed that oral gavage of AZD-2014 suppressed SQ20B xenograft growth in severe combined immunodeficient (SCID) mice. It also significantly improved mice survival. Importantly, AZD-2014’s anti-HNSCC activity in vivo was potentiated with co-administration of ABT-737. The preclinical results of this study suggest that AZD-2014 could be further tested as a valuable anti-HNSCC agent, either alone or in combination with Bcl-2 inhibitors. - Highlights: • AZD-2014 blocks mTORC1/2 activation in HNSCC cells. • AZD-2014 suppresses HNSCC cell proliferation. • AZD-2014 activates caspase-3 and apoptosis in HNSCC cells. • Bcl-2 is the key resistance factor of AZD-2014 in HNSCC cells. • ABT-737 sensitizes AZD-2014-induced anti-HNSCC activity in vivo.

  11. C-MYC and BCL2 translocation frequency in diffuse large B-cell lymphomas: A study of 97 patients.

    Science.gov (United States)

    Akkaya, Bahar; Salim, Ozan; Akkaya, Hampar; Ozcan, Mualla; Yucel, Orhan Kemal; Erdem, Ramazan; Iltar, Utku; Undar, Levent

    2016-01-01

    Diffuse large B-cell lymphoma (DLBCL) is an aggressive non-Hodgkin lymphoma with marked biologic heterogeneity. MYC and BCL2 rearrangements have been reported in a proportion of DLBCLs, where they may be associated with an adverse clinical outcome. The aim of this study was to determine the frequency of MYC and BCL2 translocations in DLBCL and assess the prognostic impact in DLBCL patients. In the present study, we evaluated the expression patterns of CD 10, BCL6, and MUM 1 by immunohistochemistry in 121 cases with DLBCL in tissue microarray (TMA): 62 cases in germinal center B-cells (GCBs); and 59 cases in activated B-cells (ABCs) of which 60 were females and 61 were males. MYC and BCL2 rearrangements were investigated by interphase fluorescence in situ hybridization on TMAs in 97 DLBCLs. MYC rearrangements were observed in 11 of 97 cases. There was no association with other clinical features, including age, sex, and nodal/extranodal disease. MYC rearrangement was associated with significantly worse overall survival (P 97 cases. There was no association with other clinical features including age and sex. BCL2 rearrangement had a worse outcome (P 97 cases with the age of  53 (female), 53, 63 years old, respectively, died in 24, 18, and 35 months after the diagnosis. Two cases had primary nodal and one case primary extranodal presentations. All these patients had stage IV disease. We concluded that C-MYC and BCL2 may contribute to aggressive transformation, and more mechanism-based therapy should be explored. Targeted therapies involving these rearrangements and its associated pathways may change the fate of DLBCLs. Analysis of MYC gene rearrangement along with BCL2 is critical in the identification of high-risk patients with poor prognosis.

  12. Pan-Bcl-2 inhibitor obatoclax delays cell cycle progression and blocks migration of colorectal cancer cells.

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    Bruno Christian Koehler

    Full Text Available Despite the fact that new treatment regimes have improved overall survival of patients challenged by colorectal cancer (CRC, prognosis in the metastatic situation is still restricted. The Bcl-2 family of proteins has been identified as promising anti cancer drug target. Even though small molecules targeting Bcl-2 proteins are in clinical trials, little is known regarding their effects on CRC. The aim of this study was to preclinically investigate the value of ABT-737 and Obatoclax as anticancer drugs for CRC treatment. The effects of the BH3-mimetics ABT-737 and Obatoclax on CRC cells were assessed using viability and apoptosis assays. Wound healing migration and boyden chamber invasion assays were applied. 3-dimensional cell cultures were used for long term assessment of invasion and proliferation. Clinically relevant concentrations of pan-Bcl-2 inhibitor Obatoclax did not induce cell death. In contrast, the BH3-mimetic ABT-737 induced apoptosis in a dose dependent manner. Obatoclax caused a cell line specific slowdown of CRC cell growth. Furthermore, Obatoclax, but not ABT-737, recovered E-Cadherin expression and led to impaired migration and invasion of CRC cells. The proliferative capacity and invasiveness of CRC cells was strikingly inhibited by low dose Obatoclax in long term 3-dimensional cell cultures. Obatoclax, but not ABT-737, caused a G1-phase arrest accompanied by a downregulation of Cyclin D1 and upregulation of p27 and p21. Overexpression of Mcl-1, Bcl-xL or Bcl-2 reversed the inhibitory effect of Obatoclax on migration but failed to restore the proliferative capacity of Obatoclax-treated CRC cells. The data presented indicate broad and multifaceted antitumor effects of the pan-Bcl-2 inhibitor Obatoclax on CRC cells. In contrast to ABT-737, Obatoclax inhibited migration, invasion and proliferation in sublethal doses. In summary, this study recommends pan-Bcl-2 inhibition as a promising approach for clinical trials in CRC.

  13. Ekspresi Gen Family Bcl-2 dan Ekspresi Gen Protein Kanal Ion Vdac1 pada Oligozoospermia

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    Arni Amir

    2014-05-01

    Full Text Available AbstrakSalah satu bentuk infertilitas pada pria adalah jumlah spermatozoa yang kurang dari normal (Oligozoospermia. Berbagai mekanisme diduga berperan dalam terjadinya oligozoospermia, mulai dari faktor fisik, stress, makanan dan molekuler. Penelitian ini merupakan kajian molekuler terhadap pengaruh ekspresi gen Bax, Bcl-2 dan VDAC terhadap terjadinya oligozoospermia. Penelitian dilakukan terhadap 40 sampel oligozoospermia dan sebagai kontrol adalah golongan normozoospermia dengan jumlah yang sama banyak. Sperma diisolasi menggunakan Percoll hypaque. Isolasi RNA menggunakan High Pure RNA isolation kit (Roche. Selanjutnya dilakukan pembuatan cDNA menggunakan First Strand cDNA synthetis (Roche. Tingkat ekspresi gen dinilai menggunakan mesin Light Cycler 2.0 (Roche. Primer didesain menggunakan software primer 3 plus dan spesifikasi primer dianalisis dengan Basic Local Alignment Search Tool (Blast. Tingkat ekspresi dibandingkan menggunakan Housekeeping gene (β-actin. Berdasarkan data penelitian diketahui tingkat ekspresi VDAC dan BAX lebih tinggi pada kelompok oligozoospermia dibanding normo (p < 0.05, namun tidak ditemukan perbedaan pada gen Bcl-2 (p > 0.05. Berdasarkan proporsi ekspresi ditemukan sebagian besar kelompok oligozoospermia mengalami overekspresi pada gen VDAC dan BAX (90% dan 93.3%, namun tidak ada overkekspresi pada normo (p>0.05. Pada penelitian ini dapat disimpulkan bahwa overekspresi VDAC dan BAC berkaitan dengan kejadian oligozoospermiaKata kunci: Oligozoospermia, VDAC, Bax, Bcl-2, ekspresi genAbstractOne form of infertility in men is the number of spermatozoa which is less than normal (Oligozoospermia. Various mechanisms though have a role in the occurrence of oligozoospermia, it can be from physical factors, stress, food and molecular.This research is a molecular study of gen expression, Bax, Bcl2 and VDAC influence of the oligozoospermia’s occurrence.The research is conducted on 40 samples of oligozoospermia and as a

  14. BET inhibition silences expression of MYCN and BCL2 and induces cytotoxicity in neuroblastoma tumor models.

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    Anastasia Wyce

    Full Text Available BET family proteins are epigenetic regulators known to control expression of genes involved in cell growth and oncogenesis. Selective inhibitors of BET proteins exhibit potent anti-proliferative activity in a number of hematologic cancer models, in part through suppression of the MYC oncogene and downstream Myc-driven pathways. However, little is currently known about the activity of BET inhibitors in solid tumor models, and whether down-regulation of MYC family genes contributes to sensitivity. Here we provide evidence for potent BET inhibitor activity in neuroblastoma, a pediatric solid tumor associated with a high frequency of MYCN amplifications. We treated a panel of neuroblastoma cell lines with a novel small molecule inhibitor of BET proteins, GSK1324726A (I-BET726, and observed potent growth inhibition and cytotoxicity in most cell lines irrespective of MYCN copy number or expression level. Gene expression analyses in neuroblastoma cell lines suggest a role of BET inhibition in apoptosis, signaling, and N-Myc-driven pathways, including the direct suppression of BCL2 and MYCN. Reversal of MYCN or BCL2 suppression reduces the potency of I-BET726-induced cytotoxicity in a cell line-specific manner; however, neither factor fully accounts for I-BET726 sensitivity. Oral administration of I-BET726 to mouse xenograft models of human neuroblastoma results in tumor growth inhibition and down-regulation MYCN and BCL2 expression, suggesting a potential role for these genes in tumor growth. Taken together, our data highlight the potential of BET inhibitors as novel therapeutics for neuroblastoma, and suggest that sensitivity is driven by pleiotropic effects on cell growth and apoptotic pathways in a context-specific manner.

  15. BCL-2 protects human and mouse Th17 cells from glucocorticoid-induced apoptosis

    Science.gov (United States)

    Banuelos, J.; Shin, S.; Cao, Y.; Bochner, B. S.; Morales-Nebreda, L.; Budinger, G. R. S.; Zhou, L.; Li, S.; Xin, J.; Lingen, M. W.; Dong, C.; Schleimer, R. P.; Lu, N. Z.

    2016-01-01

    Background Glucocorticoid resistance has been associated with Th17-driven inflammation, the mechanisms of which are not clear. We determined whether human and mouse Th17 cells are resistant to glucocorticoid-induced apoptosis. Methods Freshly isolated human blood Th17 cells and in vitro differentiated Th17 cells from IL-17F red fluorescent protein reporter mice were treated with dexamethasone, a potent glucocorticoid. Apoptosis was measured using annexin V and DAPI staining. Screening of apoptosis genes was performed using the apoptosis PCR array. Levels of molecules involved in apoptosis were measured using quantitative RT-PCR, flow cytometry, and Western blotting. Knockdown of BCL-2 in murine Th17 cells was performed via retroviral transduction. Cytokines were measured using ELISA. A murine Th17-driven severe asthma model was examined for Th17 glucocorticoid sensitivity in vivo. Results Human and mouse Th17 cells and mouse Th2 cells were resistant to glucocorticoid-induced apoptosis. Th17 cells had glucocorticoid receptors levels comparable to those in other T effectors cells. Th17 cells had high levels of BCL-2, knockdown of which sensitized Th17 cells to dexamethasone-induced apoptosis. Production of IL-22, but not IL-17A and IL-17F, was suppressed by glucocorticoids. STAT3 phosphorylation in Th17 cells was insensitive to glucocorticoid inhibition. Lung Th17 cells in the murine severe asthma model were enhanced, rather than suppressed, by glucocorticoids. Conclusion Th17 cells are resistant to glucocorticoid-induced apoptosis and cytokine suppression, at least in part due to high levels of BCL-2. These findings support a role of Th17 cells in glucocorticoid-resistant inflammatory conditions such as certain endotypes of asthma. PMID:26752231

  16. MRP- and BCL-2-mediated drug resistance in human SCLC: effects of apoptotic sphingolipids in vitro.

    Science.gov (United States)

    Khodadadian, M; Leroux, M E; Auzenne, E; Ghosh, S C; Farquhar, D; Evans, R; Spohn, W; Zou, Y; Klostergaard, J

    2009-10-01

    Multidrug-resistance-associated protein (MRP) and BCL-2 contribute to drug resistance expressed in SCLC. To establish whether MRP-mediated drug resistance affects sphingolipid (SL)-induced apoptosis in SCLC, we first examined the human SCLC cell line, UMCC-1, and its MRP over-expressing, drug-resistant subline, UMCC-1/VP. Despite significantly decreased sensitivity to doxorubicin (Dox) and to the etoposide, VP-16, the drug-selected line was essentially equally as sensitive to treatment with exogenous ceramide (Cer), sphingosine (Sp) or dimethyl-sphingosine (DMSP) as the parental line. Next, we observed that high BCL-2-expressing human H69 SCLC cells, that were approximately 160-fold more sensitive to Dox than their combined BCL-2 and MRP-over-expressing (H69AR) counterparts, were only approximately 5-fold more resistant to DMSP. Time-lapse fluorescence microscopy of either UMCC cell line treated with DMSP-Coumarin revealed comparable extents and kinetics of SL uptake, further ruling out MRP-mediated effects on drug uptake. DMSP potentiated the cytotoxic activity of VP-16 and Taxol, but not Dox, in drug-resistant UMCC-1/VP cells. However, this sensitization did not appear to involve DMSP-mediated effects on the function of MRP in drug export; nor did DMSP strongly shift the balance of pro-apoptotic Sps and anti-apoptotic Sp-1-Ps in these cells. We conclude that SL-induced apoptosis markedly overcomes or bypasses MRP-mediated drug resistance relevant to SCLC and may suggest a novel therapeutic approach to chemotherapy for these tumors.

  17. Homologous recombination control by the anti-apoptotic onco-protein Bcl-2

    International Nuclear Information System (INIS)

    Dumay, A.

    2003-12-01

    This research thesis deals with the different biological mechanisms, notably the repair and apoptosis mechanisms induced by irradiation in cells. After a presentation of the genotoxic stress and DNA repair mechanisms, the author discusses the cellular response to a DNA double-strand break, and the regulation of these response mechanisms (how a cellular response emerges: life or death). The next part deals with the apoptosis (cell death by necrosis or apoptosis), and presents the BCL-2 protein family. Results are then reported on laboratory studies of the effect of this protein family

  18. Apoptose e expressão de Bcl-2 e das caspases 3 e 8 em placenta bovina, em diferentes estádios de gestação Apoptosis and expression of Bcl-2 and caspases 3 and 8 in placenta of cows at different pregnancy stages

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    K.K.O.L. Meça

    2010-04-01

    Full Text Available Apoptose e seus mecanismos reguladores são eventos fisiológicos cruciais para a manutenção da homeostase placentária, e o desequilíbrio desses processos pode comprometer a função placentária e, consequentemente, o sucesso da gravidez. Neste estudo, investigou-se a apoptose utilizando-se histomorfometria em lâminas coradas em HE e submetidas à reação de TUNEL. Além disso, avaliou-se a expressão de Bcl-2 e das caspases 8 e 3, pela reação de polimerase em cadeia em tempo real, em placentas saudáveis em diferentes estádios de gestação. Amostras de placentônios de vacas com quatro, seis e nove meses de gestação foram colhidas e processadas. O índice apoptótico aumentou progressivamente com o avanço da gestação. Tanto o Bcl-2 quanto as caspases 3 e 8 foram expressas nos três períodos estudados, sendo a expressão de Bcl-2 menor que a de caspase 8, que é menor que a de caspase 3. Estes resultados indicam que essas moléculas estão envolvidas na via apoptótica ativada na maturação placentária, exibindo um padrão de expressão ao longo da gestação e contribuindo para o equilíbrio fisiológico da celularidade e renovação celular na placenta bovina.Apoptosis and its regulating mechanisms are crucial physiological events for the maintenance of the placental homostasis; and disequilibrium of these processes may compromise placental function and the success of the pregnancy. In this study, apoptosis was investigated by histomorphometry using slides stained with HE and TUNEL reaction. Besides that, Bcl-2 and caspases 8 and 3 expression were evaluated by real time polymerase chain reaction in healthy placentas under different gestacional ages. Samples of placentones of cows at 4th, 6th, and 9th months of gestation were harvested and processed. The apoptotic index gradually increased with the advance of the gestation. Bcl-2 and caspases 3 and 8 were expressed in all the studied periods, being the expression of Bcl-2

  19. Genetic ablation of Bcl-x attenuates invasiveness without affecting apoptosis or tumor growth in a mouse model of pancreatic neuroendocrine cancer.

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    Jeffrey H Hager

    Full Text Available Tumor cell death is modulated by an intrinsic cell death pathway controlled by the pro- and anti-apoptotic members of the Bcl-2 family. Up-regulation of anti-apoptotic Bcl-2 family members has been shown to suppress cell death in pre-clinical models of human cancer and is implicated in human tumor progression. Previous gain-of-function studies in the RIP1-Tag2 model of pancreatic islet carcinogenesis, involving uniform or focal/temporal over-expression of Bcl-x(L, demonstrated accelerated tumor formation and growth. To specifically assess the role of endogenous Bcl-x in regulating apoptosis and tumor progression in this model, we engineered a pancreatic beta-cell-specific knockout of both alleles of Bcl-x using the Cre-LoxP system of homologous recombination. Surprisingly, there was no appreciable effect on tumor cell apoptosis rates or on tumor growth in the Bcl-x knockout mice. Other anti-apoptotic Bcl-2 family members were expressed but not substantively altered at the mRNA level in the Bcl-x-null tumors, suggestive of redundancy without compensatory transcriptional up-regulation. Interestingly, the incidence of invasive carcinomas was reduced, and tumor cells lacking Bcl-x were impaired in invasion in a two-chamber trans-well assay under conditions mimicking hypoxia. Thus, while the function of Bcl-x in suppressing apoptosis and thereby promoting tumor growth is evidently redundant, genetic ablation implicates Bcl-x in selectively facilitating invasion, consistent with a recent report documenting a pro-invasive capability of Bcl-x(L upon exogenous over-expression.

  20. Correlation of mammographical imaging signs with the expression of bcl-2 and bax proteins in breast cancer

    International Nuclear Information System (INIS)

    Zhang Yili; Du Hongwen; Zhang Yun; Zhang Yuelang; Kuang Fangjun; Guo Zuomin

    2004-01-01

    Objective: To discuss the correlation of mammographical imaging signs with the expression of bcl-2 and bax proteins in breast cancer for early diagnosis and forecast of its prognoses. Methods: Fifty-four breast cancers and 26 benign diseases were proved by pathologic methods and all cases underwent mammography. Immunohistochemical technique was used to measure the expression of bcl-2 and bax proteins in these tissues. The correlation of imaging signs with the expression of bcl-2 and bax proteins in breast cancer and benign lesion was analyzed. Results: The expression of bcl-2 or bax protein in the breast cancer was higher than that in breast benign diseases (χ 2 =15.116, 11.361, P 2 =10.358, 12.818, P 2 =10.996, 10.667, P 2 =10.405, P 2 =6.841, P<0.05). Conclusion: Some imaging signs of breast cancer were closely related to the expression of bcl-2 and bax proteins and these signs could reflect the biological behavior of tumor cells and prognoses. Therefore it could be helpful to the early diagnosis and treatment of breast cancer. (authors)

  1. Inhibition of BCL2 expression and activity increases H460 sensitivity to the growth inhibitory effects of polyphenon E.

    Science.gov (United States)

    Borgovan, Theodor; Bellistri, John-Paul S; Slack, Kristen N; Kopelovich, Levy; Desai, Manisha; Joe, Andrew K

    2009-01-01

    The anti-cancer properties of the green tea-derived mixture Polyphenon E (Poly E) have been demonstrated in a variety of cell culture and animal models. We recently discovered that the H460 lung cancer cell line is markedly resistant to the growth inhibitory effects of Poly E compared with SW480 colon and Flo-1 esophageal cancer cells. We investigated the mechanism of H460 resistance by comparing gene expression profiles of Poly E-sensitive and -resistant cells. Unsupervised hierarchical clustering revealed that Poly E-sensitive cells clustered separately from Poly E-resistant cells, and 6,242 genes were differentially expressed between the two groups at the 0.01 level of significance. We discovered that BCL2 gene and protein expression were significantly higher in H460 cells compared with SW480 and Flo-1 cells (10.60-fold higher gene expression; P < 0.0001). Inhibition of BCL2 expression and activity, using siRNA and the small molecule inhibitor HA14-1 respectively, restored sensitivity to Poly E and induced BCL2-related apoptosis by decreasing mitochondrial membrane potential and inducing PARP cleavage. Our results suggest that increased BCL2 expression may contribute to H460 resistance to the growth inhibitory effects of Poly E. If validated in additional laboratory and clinical models, BCL2 could ultimately be used as a marker of Poly E resistance.

  2. Combination of erlotinib and EGCG induces apoptosis of head and neck cancers through posttranscriptional regulation of Bim and Bcl-2.

    Science.gov (United States)

    Haque, Abedul; Rahman, Mohammad Aminur; Chen, Zhuo Georgia; Saba, Nabil F; Khuri, Fadlo R; Shin, Dong M; Ruhul Amin, A R M

    2015-07-01

    Combinatorial approaches using two or more compounds are gaining increasing attention for cancer therapy. We have previously reported that the combination of the EGFR-TKI erlotinib and epigallocatechin-3-gallate (EGCG) exhibited synergistic chemopreventive effects in head and neck cancers by inducing the expression of Bim, p21, p27, and by inhibiting the phosphorylation of ERK and AKT and expression of Bcl-2. In the current study, we further investigated the mechanism of regulation of Bim, Bcl-2, p21 and p27, and their role in apoptosis. shRNA-mediated silencing of Bim significantly inhibited apoptosis induced by the combination of erlotinib and EGCG (p = 0.005). On the other hand, overexpression of Bcl-2 markedly protected cells from apoptosis (p = 0.003), whereas overexpression of constitutively active AKT only minimally protected cells from apoptosis induced by the combination of the two compounds. Analysis of mRNA expression by RT-PCR revealed that erlotinib, EGCG and their combination had no significant effects on the mRNA expression of Bim, p21, p27 or Bcl-2 suggesting the post-transcriptional regulation of these molecules. Furthermore, we found that erlotinib or the combination of EGCG and erlotinib inhibited the phosphorylation of Bim and stabilized Bim after inhibition of protein translation by cycloheximide. Taken together, our results strongly suggest that the combination of erlotinib and EGCG induces apoptosis of SCCHN cells by regulating Bim and Bcl-2 at the posttranscriptional level.

  3. Transcription Factor Bcl11b Controls Effector and Memory CD8 T cell Fate Decision and Function During Poxvirus Infection

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    Georges Abboud

    2016-10-01

    Full Text Available CD8+ T cells play an important role in host resistance to many viral infections, but the underlying transcriptional mechanisms governing their differentiation and functionality remain poorly defined. By using a highly virulent systemic and respiratory poxvirus infection in mice, we show that the transcription factor Bcl11b provides a dual trigger that sustains the clonal expansion of virus-specific effector CD8+ T cells, while simultaneously suppressing the expression of surface markers associated with short-lived effector cell (SLEC differentiation. Additionally, we demonstrate that Bcl11b supports the acquisition of memory precursor effector cell (MPEC phenotype, and thus its absence causes near complete loss of lymphoid and lung-resident memory cells. Interestingly, despite having normal levels of T-bet and Eomesodermin, Bcl11b-deficient CD8+ T cells failed to execute effector differentiation needed for anti-viral cytokine production and degranulation, suggesting a non-redundant role of Bcl11b in regulation of this program. Thus, Bcl11b is a critical player in fate decision of SLECs and MPECs, as well as effector function and memory formation.

  4. Deletion of AU-rich elements within the Bcl2 3'UTR reduces protein expression and B cell survival in vivo.

    Directory of Open Access Journals (Sweden)

    Manuel D Díaz-Muñoz

    Full Text Available Post-transcriptional mRNA regulation by RNA binding proteins (RBPs associated with AU-rich elements (AREs present in the 3' untranslated region (3'UTR of specific mRNAs modulates transcript stability and translation in eukaryotic cells. Here we have functionally characterised the importance of the AREs present within the Bcl2 3'UTR in order to maintain Bcl2 expression. Gene targeting deletion of 300 nucleotides of the Bcl2 3'UTR rich in AREs diminishes Bcl2 mRNA stability and protein levels in primary B cells, decreasing cell lifespan. Generation of chimeric mice indicates that Bcl2-ARE∆/∆ B cells have an intrinsic competitive disadvantage compared to wild type cells. Biochemical assays and predictions using a bioinformatics approach show that several RBPs bind to the Bcl2 AREs, including AUF1 and HuR proteins. Altogether, association of RBPs to Bcl2 AREs contributes to Bcl2 protein expression by stabilizing Bcl2 mRNA and promotes B cell maintenance.

  5. Reciprocal occupancy of BCL6 and STAT5 on Growth Hormone target genes: contrasting transcriptional outcomes and promoter-specific roles of p300 and HDAC3.

    Science.gov (United States)

    Lin, Grace; LaPensee, Christopher R; Qin, Zhaohui S; Schwartz, Jessica

    2014-09-01

    Expression of the Growth Hormone (GH)-stimulated gene Socs2 (Suppressor of Cytokine Signaling 2) is mediated by the transcription activator STAT5 (Signal Transducer and Activator of Transcription 5) and the transcription repressor BCL6 (B-Cell Lymphoma 6). ChIP-Sequencing identified Cish (Cytokine-Inducible SH2-containing protein) and Bcl6 as having similar patterns of reciprocal occupancy by BCL6 and STAT5 in response to GH, though GH stimulates Cish and inhibits Bcl6 expression. The co-activator p300 occupied Socs2, Cish and Bcl6 promoters, and enhanced STAT5-mediated activation of Socs2 and Cish. In contrast, on Bcl6, p300 functioned as a repressor and inhibited in conjunction with STAT5 or BCL6. The co-repressor HDAC3 (Histone deacetylase 3) inhibited the Socs2, Cish and Bcl6 promoters in the presence of STAT5. Thus transcriptional outcomes on GH-regulated genes occupied by BCL6 and STAT5 are determined in a promoter-specific fashion by co-regulatory proteins which mediate the distinction between activating and repressive transcription factors. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  6. Overexpression of Bcl-2, SOCS 1, 3 and Cdh 1, 2 are associated with the early neoplasic changes in modified 4-nitroquinoline 1-oxide-induced murine oral cancer model.

    Science.gov (United States)

    Cabrera Ortega, Adriana Alicia; Gonçalves, Vinícius de Paiva; Guimarães, Morgana Rodrigues; Rossa Junior, Carlos; Spolidorio, Luis Carlos

    2016-09-01

    The objective was to assess histopathological changes and the expression of proliferating cell nuclear antigen (PCNA), Bcl-2, suppressor of cytokine signaling (SOCS) 1 and 3, Vimentin, TWIST1, and Cdh 1 and 2 in early stages of experimental oral carcinogenesis process using a shorter period of exposure to 4-nitroquinoline oxide (4-NQO) model. In this study, 20 rats were divided into control group (n = 10), sacrificed on the first day of the experiment, and experimental group (n = 10) treated with 50 ppm of 4-NQO solution dissolved in drinking water for 8 and 12 weeks. The histological sections were stained with H&E or subjected to immunohistochemistry for detecting PCNA, Bcl-2, SOCS 1 and 3, and STAT 3. Some specimens were used for verification of Vimentin expression, Cdh 1, Cdh 2, and TWIST1 by RT-qPCR. At both 8 and 12 weeks, morphological changes occurred mainly in the posterior portion of the tongue and were limited to the epithelial tissue, including moderate to severe dysplasia at 8 weeks, and severe dysplasia with exacerbation of atypical cells at 12 weeks. Expression of SOCS 1 and 3 increased from 8 to 12 weeks (P Cdh 1 and 2. Together, the results suggested that overexpression of Bcl-2, SOCS 1 and 3, and Cdh 1 and 2 is associated with the early neoplasic changes in modified 4-nitroquinoline 1-oxide-induced murine oral cancer model. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  7. Involvement of Bcl-2-associated athanogene (BAG)-family proteins in the neuroprotection by rasagiline.

    Science.gov (United States)

    Guo, Ji-Feng; He, Shuang; Kang, Ji-Feng; Xu, Qian; Hu, Ya-Cen; Zhang, Hai-Nan; Wang, Chun-Yu; Yan, Xin-Xiang; Tang, Bei-Sha

    2015-01-01

    Rasagiline, a novel monoamine oxidase (MAO)-B inhibitor, has a mild to moderate effect in relieving Parkinson's disease (PD) symptoms as well as unique neuroprotective effects. Previous studies demonstrated rasagiline protect neurons by regulating Bcl-2 family proteins. Our study aimed to study whether Bcl-2-associated athanogene (BAG)-family proteins, which were reported closely associated with neurodegenerative disease, were involved in the neuroprotective effect of rasagiline. We found that after the administration of 1-methy1-4-phenvl-1,2,3,6-tetrahvdropvridine (MPTP), BAG2 and BAG5 proteins were up-regulated in the substantia nigra dopaminergic neurons of PD mouse model. A further increase of BAG2 and BAG5 was detected after intragastric administration of rasagiline to post-MPTP lesioned mice. Thus, the current study proved the association of BAG family proteins with PD, and suggested the involvement and a positive role of BAG2, BAG5 in the neuroprotection of rasagiline. These preliminary results implicate a novel pathway for further study on neuroprotection of rasagiline.

  8. Regulation of apoptosis through bcl-2/bax proteins expression and DNA damage by Zanthoxylum alatum.

    Science.gov (United States)

    Karmakar, Indrajit; Haldar, Sagnik; Chakraborty, Mainak; Chaudhury, Keya; Dewanjee, Saikat; Haldar, Pallab Kanti

    2016-01-01

    Many of the major chemotherapeutic agents are secondary metabolites found in nature. Zanthoxylum alatum Roxb. (Rutaceae) is traditionally used in the treatment of various diseases. The present study evaluates the apoptotic activity of methanol extract of Z. alatum (MEZA) on Ehrlich ascites tumor (EAT) in Swiss albino mice. The presence of flavonoids in MEZA was standardized by HPLC. The in vitro cytotoxicity of MEZA was measured by the MTT assay. The in vivo antitumor activity of MEZA (100 and 200 mg/kg b.w., i.p. for 9 days) was also evaluated. On the 10th day, EAT tumor volume, cell viability, and hematological parameters were assayed. Apoptotic morphology was determined by acredine orange/ethedium bromide using fluorescence microscopy. Apoptosis percentage was measured by flow cytometric analysis using annexine-V-FITC. Also, DNA damage and bcl-2/bax were estimated by UV-method and western blot, respectively. HPLC analysis revealed presence of three flavonoids, rutin, myricetin, and quercetin. MEZA showed satisfactory cytotoxicity in MTT assay (IC50 = 111.50 µg/ml). The extract significantly (p < 0.01) changed the tumor volume, viable, non-viable cell count, and hematological parameters towards the normal. Apoptotic activity of MEZA was confirmed by acridine orange/ethidium bromide staining, annexin-V-FITC staining, DNA fragmentation, and Bcl-2/Bax ratio. The study showed that MEZA has antitumor activity which may be due to the presence of flavonoids in the extract.

  9. Decreased Bcl-6 and increased Blimp-1 in the peritoneal cavity of patients with endometriosis.

    Science.gov (United States)

    Yeol, S G; Won, Y S; Kim, Y I; Lee, J W; Choi, Y J; Park, D C

    2015-01-01

    The authors investigated the expression patterns of interleukin (IL)-lβ and tumor necrosis factor (TNF)-α, cytokines associated with peritoneal inflammatory reactions, and of B cell leukemia lymphoma (Bcl)-6 and B lymphocyte inducer of maturation program (Blimp)-1, transcriptional factors associated with immunoglobulin (Ig) production; the concentrations of Igs, and their correlation, in patients with and without endometriosis. The authors analyzed the peritoneal fluid of 98 patients, 46 with endometriosis, and 52 with benign tumors. IL-1 and TNF-α mRNAs and IgG and IgA concentrations were higher in the endometriosis group, but the differences were not statistically significant. However, Bcl-6 mRNA level was significantly lower and Blimp-1 mRNA level was significantly higher in the endometriosis group with significant correlations among transcriptional factors, Igs, and cytokines (p Peritoneal immune responses in patients with endometriosis may be due to increased IgG and IgA concentrations, as well as to changes in expression of proinflammatory cytokines and transcriptional factors.

  10. The prognostic significance of the immunohistochemical expression of P53 and BCL-2 in endometrial cancer

    Directory of Open Access Journals (Sweden)

    Lech Chyczewski

    2012-01-01

    Full Text Available The objective of this study was to verify the frequency of P53 and BCL-2 immunohistochemical expression in 98 patients with endometrial carcinoma, and to correlate it with clinical stage and patient survival. A significant difference was found regarding the frequency of P53 expression when comparing type I and II tumors (23.7% and 54.5%, respectively; p = 0.006. A positive correlation was observed between P53 immunoexpression and patient survival in type I and II tumors (p = 0.009 and p = 0.036, respectively. BCL-2 expression was significantly more frequent in early clinical stages in both types of endometrial cancer (p < 0.001 and 0.002 and correlated with a decrease in overall survival in type I endometrial cancer (p = 0.014. Thus, the prognostic value of these biomarkers in endometrial cancer needs to be further investigated. (Folia Histochemica et Cytobiologica 2011; Vol. 49, No. 4, pp. 631–635

  11. Exhaustive Training Increases Uncoupling Protein 2 Expression and Decreases Bcl-2/Bax Ratio in Rat Skeletal Muscle

    Directory of Open Access Journals (Sweden)

    W. Y. Liu

    2013-01-01

    Full Text Available This work investigates the effects of oxidative stress due to exhaustive training on uncoupling protein 2 (UCP2 and Bcl-2/Bax in rat skeletal muscles. A total of 18 Sprague-Dawley female rats were randomly divided into three groups: the control group (CON, the trained control group (TC, and the exhaustive trained group (ET. Malondialdehyde (MDA, superoxide dismutase (SOD, xanthine oxidase (XOD, ATPase, UCP2, and Bcl-2/Bax ratio in red gastrocnemius muscles were measured. Exhaustive training induced ROS increase in red gastrocnemius muscles, which led to a decrease in the cell antiapoptotic ability (Bcl-2/Bax ratio. An increase in UCP2 expression can reduce ROS production and affect mitochondrial energy production. Thus, oxidative stress plays a significant role in overtraining.

  12. BCL11B Drives Human Mammary Stem Cell Self-Renewal In Vitro by Inhibiting Basal Differentiation

    Directory of Open Access Journals (Sweden)

    Daniel H. Miller

    2018-03-01

    Full Text Available Summary: The epithelial compartment of the mammary gland contains basal and luminal cell lineages, as well as stem and progenitor cells that reside upstream in the differentiation hierarchy. Stem and progenitor cell differentiation is regulated to maintain adult tissue and mediate expansion during pregnancy and lactation. The genetic factors that regulate the transition of cells between differentiation states remain incompletely understood. Here, we present a genome-scale method to discover genes driving cell-state specification. Applying this method, we identify a transcription factor, BCL11B, which drives stem cell self-renewal in vitro, by inhibiting differentiation into the basal lineage. To validate BCL11B's functional role, we use two-dimensional colony-forming and three-dimensional tissue differentiation assays to assess the lineage differentiation potential and functional abilities of primary human mammary cells. These findings show that BCL11B regulates mammary cell differentiation and demonstrate the utility of our proposed genome-scale strategy for identifying lineage regulators in mammalian tissues. : Miller et al. describe a strategy to identify candidate master regulators of cell lineage specification. This approach identified BCL11B as a key regulator of human mammary stem cell self-renewal in in vitro progenitor and differentiation assays. Using a combination of 2D and 3D primary cell culture techniques, they show that BCL11B drives stem cell self-renewal by inhibiting basal lineage commitment. Keywords: human mammary gland biology, mammary epithelial stem cells, BCL11B, epigenetics, single-cell genomics, epithelial differentiation, three-dimensional cell culture

  13. Bcl-2 family members make different contributions to cell death in hypoxia and/or hyperoxia in rat cerebral cortex.

    Science.gov (United States)

    Hu, Xiaoming; Qiu, Jingxin; Grafe, Marjorie R; Rea, Harriett C; Rassin, David K; Perez-Polo, J Regino

    2003-11-01

    Hypoxic brain injury during fetal or neonatal development leads to damaged immature neurons and can result in cognitive or behavioral dysfunction. Hyperoxia therapy (treatment with oxygen) is commonly applied to infants with signs of perinatal hypoxia-anoxia. Both hypoxia and hyperoxia have been shown to result in apoptosis in the brains of rats in several animal models. One determinant of cellular commitment to cell death is the differential expression of the Bcl-2 family of proteins in response to trauma. Here, we characterize cell death and the expression of Bcl-2 homologous proteins in 7-day-old neonatal rat cerebral cortex after hypoxia (5% O(2) for 40 min) and/or hyperoxia (>95% O(2) for 2 h after hypoxia). The expression of Bcl-2 and Bcl-X(L), two anti-apoptotic proteins, decreased at 24 h after hypoxia. Bcl-X(L) increased after either hyperoxia or hypoxia+hyperoxia. We did not detect significant changes in the cytoplasmic levels of pro-apoptotic protein Bax after any of these three treatments. Using cell death ELISA and DNA FragEL assays, we observed increased cell death at 24h after hypoxia, hyperoxia or hypoxia+hyperoxia treatments. At 24 h after either hypoxia, hyperoxia or hypoxia+hyperoxia, caspase 3 activity also increased significantly. Our results suggest that both hypoxia and hyperoxia alone can induce cell death. The Bcl-2 --> cytochrome c --> caspase 3 pathway played a role in hypoxia-induced cell death, while other pathways may be involved in hyperoxia-induced cell death.

  14. Evaluation of multiple bio-pathological factors in colorectal adenocarcinomas: independent prognostic role of p53 and bcl-2.

    Science.gov (United States)

    Buglioni, S; D'Agnano, I; Cosimelli, M; Vasselli, S; D'Angelo, C; Tedesco, M; Zupi, G; Mottolese, M

    1999-12-22

    About 40% of patients with colorectal carcinoma will develop local or distant tumour recurrences. Integrated analyses of bio-pathological markers, predictive of tumour aggressiveness, may offer a more rational approach to planning adjuvant therapy. To this end, we analysed the correlation between p53 accumulation, Bcl-2 expression, DNA ploidy, cell proliferation and conventional clinico-pathological parameters by testing the prognostic significance of these variables in a series of 171 colorectal carcinoma patients with long-term follow-up. The relationships among the various bio-pathological parameters, analysed by multiple correspondence analysis, showed 2 different clinico-biological profiles. The first, characterised by p53 negativity, Bcl-2 positivity, diploidy, low percentage of cells in S-phase (%S-phase), a low Ki-67 score, is associated with Dukes' A-B stage, well differentiated tumours and lack of relapse. The second, defined by p53 positivity, Bcl-2 negativity, aneuploidy, high %S-phase and elevated Ki-67 score, correlates with Dukes' C-D stage, poorly differentiated tumours and presence of relapse. When these parameters were examined according to Kaplan-Meier's method, significantly shorter disease-free (DFS) and overall survival (OS) were also observed in patients bearing p53 positive and Bcl-2 negative tumours, in Dukes' B stage. In multivariate analysis, p53 accumulation and Bcl-2 expression emerged as independent predictors of a worse and better clinical outcome, respectively. Our results indicate that, in colorectal adenocarcinomas, a biological profile, based on the combined evaluation of p53 and Bcl-2, may be useful for identifying high risk patients to be enrolled in an adjuvant setting, mainly in an early stage of the disease. Int. J. Cancer (Pred. Oncol.) 84:545-552, 1999. Copyright 1999 Wiley-Liss, Inc.

  15. Molecular basis for the interplay of apoptosis and proliferation mediated by Bcl-xL:Bim interactions in pancreatic cancer cells

    International Nuclear Information System (INIS)

    Abrol, Ravinder; Edderkaoui, Mouad; Goddard, William A.; Pandol, Stephen J.

    2012-01-01

    Highlights: ► Direct role of Bcl-2 protein interactions in cell proliferation is not clear. ► Designed Bcl-xL mutants show opposite effects on apoptosis and proliferation. ► Disrupting Bcl-xL:Bim interaction increased apoptosis in pancreatic cancer. ► Disrupting Bcl-xL:Bim interaction decreased proliferation in pancreatic cancer. ► Bcl-xL:Bim interaction can control both apoptosis and proliferation. -- Abstract: A major mechanism through which cancer cells avoid apoptosis is by promoting the association of anti-apoptotic members of the pro-survival Bcl-2 protein family (like Bcl-2 and Bcl-xL) with BH 3 domain-only proteins (like Bim and Bid). Apoptosis and cell proliferation have been shown to be linked for many cancers but the molecular basis for this link is far from understood. We have identified the Bcl-xL:Bim protein–protein interface as a direct regulator of proliferation and apoptosis in pancreatic cancer cells. We were able to predict and subsequently verify experimentally the effect of various Bcl-xL single-point mutants (at the position A142) on binding to Bim by structural analysis and computational modeling of the inter-residue interactions at the Bcl-xL:Bim protein–protein interface. The mutants A142N, A142Q, and A142Y decreased binding of Bim to Bcl-xL and A142S increased this binding. The Bcl-xL mutants, with decreased affinity for Bim, caused an increase in apoptosis and a corresponding decrease in cell proliferation. However, we could prevent these effects by introducing a small interfering RNA (siRNA) targeted at Bim. These results show a novel role played by the Bcl-xL:Bim interaction in regulating proliferation of pancreatic cancer cells at the expense of apoptosis. This study presents a physiologically relevant model of the Bcl-xL:Bim interface that can be used for rational therapeutic design for the inhibition of proliferation and cancer cell resistance to apoptosis.

  16. BCL6 interacting corepressor contributes to germinal center T follicular helper cell formation and B cell helper function

    OpenAIRE

    Yang, Jessica A.; Tubo, Noah J.; Gearhart, Micah D.; Bardwell, Vivian J.; Jenkins, Marc K.

    2015-01-01

    CD4+ germinal center (GC) T follicular helper (GC-Tfh) cells help B cells become long-lived plasma cells and memory cells. The transcriptional repressor BCL6 plays a key role in GC-Tfh formation by inhibiting the expression of genes that promote differentiation into other lineages. We determined whether BCOR, a component of a Polycomb repressive complex that interacts with the BCL6 BTB domain, influences GC-Tfh differentiation. T cell-targeted BCOR deficiency led to a substantial loss of pept...

  17. Interferon γ is a STAT1-dependent direct inducer of BCL6 expression in imatinib-treated chronic myeloid leukemia cells.

    Science.gov (United States)

    Madapura, H S; Nagy, N; Ujvari, D; Kallas, T; Kröhnke, M C L; Amu, S; Björkholm, M; Stenke, L; Mandal, P K; McMurray, J S; Keszei, M; Westerberg, L S; Cheng, H; Xue, F; Klein, G; Klein, E; Salamon, D

    2017-08-10

    B-cell CLL/lymphoma 6 (BCL6) exerts oncogenic effects in several human hematopoietic malignancies including chronic myeloid leukemia (CML), where BCL6 expression was shown to be essential for CML stem cell survival and self-renewal during imatinib mesylate (IM) treatment. As several lines of evidence suggest that interferon γ (IFNγ) production in CML patients might have a central role in the response to tyrosine kinase inhibitor (TKI) therapy, we analyzed if IFNγ modulates BCL6 expression in CML cells. Although separate IFNγ or IM treatment only slightly upregulated BCL6 expression, combined treatment induced remarkable BCL6 upregulation in CML lines and primary human CD34+ CML stem cells. We proved that during combined treatment, inhibition of constitutive signal transducer and activator of transcription (STAT) 5 activation by IM allowed the specific enhancement of the STAT1 dependent, direct upregulation of BCL6 by IFNγ in CML cells. By using colony-forming assay, we found that IFNγ enhanced the ex vivo colony or cluster-forming capacity of human CML stem cells in the absence or presence of IM, respectively. Furthermore, inhibition of the transcriptional repressor function of BCL6 in the presence of IM and IFNγ almost completely blocked the cluster formation of human CML stem cells. On the other hand, by using small interfering RNA knockdown of BCL6, we demonstrated that in an IM-treated CML line the antiapoptotic effect of IFNγ was independent of BCL6 upregulation. We found that IFNγ also upregulated several antiapoptotic members of the BCL2 and BIRC gene families in CML cells, including the long isoform of MCL1, which proved to be essential for the antiapoptotic effect of IFNγ in an IM-treated CML line. Our results suggest that combination of TKIs with BCL6 and MCL1 inhibitors may potentially lead to the complete eradication of CML stem cells.

  18. Effects of daphnetin combined with Bcl2‑siRNA on antiapoptotic genes in synovial fibroblasts of rats with collagen‑induced arthritis.

    Science.gov (United States)

    Chen, Xiaoying; Kuang, Nanzhen; Zeng, Xiaoping; Zhang, Zhiqin; Li, Yanyan; Liu, Wei; Fu, Yingyuan

    2018-01-01

    The aim of the present study was to investigate the effects of daphnetin combined with B cell lymphoma 2 (Bcl2)‑targeted small interfering (si)RNA (si‑Bcl2) on antiapoptotic genes in fibroblast‑like synoviocytes (FLS) in rats with collagen II‑induced arthritis (CIA). The roles of si‑Bcl2 and daphnetin were determined by measuring the expression levels of Bcl2. Protein and mRNA expression levels of Bcl2 in FLS were determined by flow cytometry and reverse transcription‑quantitative polymerase chain reaction. Apoptosis of FLS was also determined by flow cytometry. It was revealed that treatment with si‑Bcl2 or daphnetin alone resulted in downregulation of Bcl2 mRNA and protein expression. In addition, the mRNA expression levels of the signal transducer and activator of transcription 3 (STAT3), which transcriptionally regulates the activity of mitochondria, were reduced. The combination of si‑Bcl2 and daphnetin exhibited an enhanced effect on rheumatoid arthritis FLS (RAFLS), in which the apoptotic rate was significantly higher than either treatment alone. The results suggested that si‑Bcl combined with daphnetin may have an enhanced effect in promoting apoptosis of RAFLS derived from CIA rats, and a possible underlying molecular mechanism may function through the downregulation of Bcl2 expression and STAT3, which is located upstream of Bcl2 in the mitochondrial apoptotic pathway. The results of the present study are expected to provide theoretical and experimental basis for the treatment of RA and the medicinal development of daphnetin combined siRNA.

  19. The elevated activation of NFκB and AP-1 is correlated with differential regulation of Bcl-2 and associated with oral squamous cell carcinoma progression and resistance.

    Science.gov (United States)

    Alam, Manzar; Kashyap, Tanushree; Pramanik, Kamdeo K; Singh, Abhay K; Nagini, Siddavaram; Mishra, Rajakishore

    2017-12-01

    Oral cancer is the sixth most common cancer in the world. Failure of chemoradiation therapy is a major concern for treating oral cancer patients. The objective of this study is to determine the B cell lymphoma-2 (bcl-2) expression and its regulation by nuclear factor κB (NFκB) and activator protein 1 (AP-1) in oral cancer progression and chemoradiation resistance. In the present study, a total of 123 (n = 123) human samples were included. Briefly, 64 fresh samples were from adjacent normal (AN), primary oral tumors without treatment (PT), and tumors with resistance to chemoradiation therapy with local recurrence (RCRT). Fifty-nine samples were human tongue cancers and normal samples (TMA). Messenger RNA (mRNA) expression levels of bcl-2 and protein levels of bcl-2, NFκB, AP-1, and inactive GSK3α/β were measured by semiquantitative RT-PCR, immunohistochemistry, Western blot, and ChIP analysis. Increased bcl-2 expression was observed in PT compared to AN. The RCRT tumors showed maximum expression of bcl-2 mRNA and protein over the PT and AN groups. Bcl-2 protein and mRNA expression were positively correlated with NFκB and AP-1 expression. AP-1 expression was strongly correlated with bcl-2 in the RCRT group of tumors. Further, inactive GSK3α/β showed a positive trend with bcl-2 expression in oral tongue cancer specimens. Collectively, our results demonstrated cumulative effect of AP-1 and NFĸB for bcl-2 gene regulation in overall PT progression and chemoradiation resistance. The study provides evidence of increased bcl-2 mRNA/protein fueled by NFĸB in PT and AP-1 in RCRT. These regulations of bcl-2 by NFκB and AP-1 are important in OSCC progression and chemoradiation resistance.

  20. Prostatic neuroendocrine cells have a unique keratin expression pattern and do not express Bcl-2: cell kinetic features of neuroendocrine cells in the human prostate

    NARCIS (Netherlands)

    Xue, Y.; Verhofstad, A.; Lange, W.; Smedts, F.; Debruyne, F.; de la Rosette, J.; Schalken, J.

    1997-01-01

    We investigated the keratin phenotype and bcl-2 immunoreactivity of neuroendocrine cells in the human prostate to determine whether the postmitotic status of these cells is associated with protection from apoptosis by bcl-2 protein expression and to elucidate the possible cell kinetic relationship

  1. A senescence rescue screen identifies BCL6 as an inhibitor of anti-proliferative p19ARF-p53 signaling

    NARCIS (Netherlands)

    Shvarts, A.; Brummelkamp, T.; Koh, E.; Daley, G.Q.; Bernards, R.A.

    2002-01-01

    Senescence limits the proliferative capacity of primary cells in culture. We describe here a genetic screen to identify genes that allow bypass of this checkpoint. Using retroviral cDNA expression libraries, we identify BCL6 as a potent inhibitor of senescence. BCL6 is frequently activated in

  2. BCL2L1 has a functional role in colorectal cancer and its protein expression is associated with chromosome 20q gain

    NARCIS (Netherlands)

    Sillars-Hardebol, A.H.; Carvalho, B.; Belien, J.A.M.; de Wit, M.; Delis-van Diemen, P.M.; Tijssen, M.; van de Wiel, M.A.; Ponten, F.; Fijneman, R.J.A.; Meijer, G.A.

    2012-01-01

    Colorectal cancer (CRC) is the second leading cause of cancer death in the western world. The majority of CRCs, which develop from adenoma precursor lesions, show gain of chromosome arm 20q, where BCL2L1 is located. BCL2L1 is an important apoptosis regulating gene that codes for both an

  3. HA14-1 selectively induces apoptosis in Bcl-2-overexpressing leukemia/lymphoma cells, and enhances cytarabine-induced cell death.

    Science.gov (United States)

    Lickliter, J D; Wood, N J; Johnson, L; McHugh, G; Tan, J; Wood, F; Cox, J; Wickham, N W

    2003-11-01

    The Bcl-2 oncoprotein is commonly overexpressed in hematological malignancy, where it promotes the survival of neoplastic cells. Recently, a small molecule (HA14-1) was reported to bind the surface pocket of Bcl-2 that mediates antiapoptotic interactions, triggering apoptosis in a Bcl-2-transfected cell line. We investigated the activity of this compound in a panel of malignant hematopoietic cell lines. Consistent with its proposed role as a Bcl-2 inhibitor, HA14-1 was most cytotoxic in lines expressing high levels of Bcl-2. In addition, at lower concentrations (5-12.5 muM), the compound predominantly triggered apoptosis. However, at concentrations two-fold higher than this and above, increasing primary necrosis was observed, suggesting the onset of interactions supplementary to Bcl-2 inhibition. In experiments on primary cells, 25 muM HA14-1 induced extensive apoptosis in acute leukemic blasts, but also suppressed normal hematopoietic colony formation to <50% of baseline. Importantly, low-concentration HA14-1 (5 muM) was nontoxic to normal colony-forming cells, whereas it enhanced the cytotoxicity of the antileukemia drug cytarabine in Bcl-2-positive lymphoblastic leukemia cells. In conclusion, our results indicate that HA14-1 at low concentration selectively triggers apoptosis in malignant hematopoietic cells that overexpress Bcl-2. Agents of this class may have particular utility in combination with cytotoxic chemotherapy drugs.

  4. Xanthurenic acid translocates proapoptotic Bcl-2 family proteins into mitochondria and impairs mitochondrial function

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    Hess Otto M

    2004-04-01

    Full Text Available Abstract Background Xanthurenic acid is an endogenous molecule produced by tryptophan degradation, produced in the cytoplasm and mitochondria. Its accumulation can be observed in aging-related diseases, e.g. senile cataract and infectious disease. We previously reported that xanthurenic acid provokes apoptosis, and now present a study of the response of mitochondria to xanthurenic acid. Results Xanthurenic acid at 10 or 20 μM in culture media of human aortic smooth muscle cells induces translocation of the proteins Bax, Bak, Bclxs, and Bad into mitochondria. In 20 μM xanthurenic acid, Bax is also translocated to the nucleus. In isolated mitochondria xanthurenic acid leads to Bax and Bclxs oligomerization, accumulation of Ca2+, and increased oxygen consumption. Conclusion Xanthurenic acid interacts directly with Bcl-2 family proteins, inducing mitochondrial pathways of apoptosis and impairing mitochondrial functions.

  5. Regulation of Caspase-3 and Bcl-2 Expression in Dalton's Lymphoma Ascites Cells by Abrin

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    V. Ramnath

    2009-01-01

    Full Text Available The role of abrin, a toxic lectin isolated from seeds of Abrus precatorius Linn in inducing apoptosis in murine Dalton's Lymphoma Ascites (DLA cells was evaluated. Abrin when incubated at the concentration of 10 ng per million DLA cells could bring about cell death as typical morphological changes with apoptosis. However, necrotic cell death dominated when a higher dose of abrin was used. DNA samples, isolated from DLA cells treated with abrin showed fragmentation. Abrin brought about induction of apoptosis by stimulating the expression of pro-apoptotic Caspase-3, at the same time blocking the expression of Bcl-2, which is an anti apoptotic gene. However, the expression of tumor suppressor gene p53 has not been observed in control and abrin-treated DLA cells. Results suggested that abrin effectively induced apoptotic changes in the tumor cells that led to cellular death.

  6. The relationship between bcl-2 expression and response to chemotherapy in acute leukaemia.

    Science.gov (United States)

    Maung, Z T; MacLean, F R; Reid, M M; Pearson, A D; Proctor, S J; Hamilton, P J; Hall, A G

    1994-09-01

    Immunocytochemistry was used to assess bcl-2 expression in blasts obtained from the bone marrow of 28 patients with acute lymphoblastic leukaemia (ALL) (16 children and six adults at presentation and three children and three adults on relapse) and 20 with acute myeloid leukaemia (AML) (19 adults and one child, 13 with de novo AML, 11 at presentation and two on relapse, and seven secondary to myelodysplasia or chronic myeloid leukaemia). Slides were examined both for the percentage of positive cells and for the intensity of staining using a five-point scale. There was a statistically significant increase in both the percentage of positive cells seen (P presentation in ALL. There was a significantly greater intensity of staining in cells from patients with ALL (P important prognostic feature in both de novo AML and in ALL, but not in secondary AML.

  7. The pro-apoptotic Bcl-2 family member tBid localizes to mitochondrial contact sites

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    Perkins Guy A

    2001-11-01

    Full Text Available Abstract Background Following cleavage by caspase 8, the C-terminus of Bid translocates from the cytosol to the mitochondria that is dependent upon structures formed by the mitochondrial-specific lipid cardiolipin. Once associated with mitochondria, truncated Bid (tBid causes the potent release of cytochrome c, endonuclease G, and smac. Results We investigated whether tBid localizes specifically to the contact sites of mitochondria purported to be rich in cardiolipin. A point mutation changing the glycine at position 94 to glutamic acid in the BH3 domain of tBid (tBidG94E was principally used because mitochondria treated with this mutant tBid displayed better preservation of the outer membrane than those treated with wild type tBid. Additionally, tBidG94E lowers the cytochrome c releasing activity of tBid without affecting its targeting to mitochondria. Electron microscope tomography coupled with immunogold labeling was used as a new hybrid technique to investigate the three-dimensional distributions of tBid and tBidG94E around the mitochondrial periphery. The statistics of spatial point patterns was used to analyze the association of these proteins with contact sites. Conclusions Immunoelectron tomography with statistical analysis confirmed the preferential association of tBid with mitochondrial contact sites. These findings link these sites with cardiolipin in tBid targeting and suggest a role for Bcl-2 family members in regulating the activity of contact sites in relation to apoptosis. We propose a mechanism whereby Bcl-2 proteins alter mitochondrial function by disrupting cardiolipin containing contact site membranes.

  8. Folate-decorated PEGylated triblock copolymer as a pH/reduction dual-responsive nanovehicle for targeted intracellular co-delivery of doxorubicin and Bcl-2 siRNA.

    Science.gov (United States)

    Suo, Aili; Qian, Junmin; Xu, Minghui; Xu, Weijun; Zhang, Yaping; Yao, Yu

    2017-07-01

    Co-delivery of chemotherapeutic drug and small interfering RNA (siRNA) within a single nanovehicle has emerged as a promising combination therapy approach to treating cancers because of their synergistic effect. Nanocarrier delivery systems with low cytotoxicity and high efficiency are needed for such a purpose. In this study, a novel folate-conjugated PEGylated cationic triblock copolymer, poly(acrylhydrazine)-block-poly(3-dimethylaminopropyl methacrylamide)-block-poly(acrylhydrazine) (PAH-b-PDMAPMA-b-PAH), was synthesized and evaluated as a stimuli-sensitive vehicle for the targeted co-delivery of doxorubicin (DOX) and Bcl-2 siRNA into breast cancer MCF-7 cells. The synthetic process of the PEGylated triblock copolymer involved sequential reversible addition-fragmentation chain transfer polymerization, PEGylation and removal of tert-butoxy carbamate protecting groups. Folate-conjugated and/or -unconjugated poly(ethylene glycol) segments were grafted onto PAH-b-PDMAPMA-b-PAH via a reduction-sensitive disulfide linkage. The synthetic polymers were characterized by 1 H NMR and gel permeation chromatography. The PEGylated triblock copolymer could chemically conjugate DOX onto PAH blocks via pH-responsive hydrazone bonds and simultaneously complex negatively charged Bcl-2 siRNA with cationic PDMAPMA blocks through electrostatic interactions at N/P ratios≥32:1 to form multifunctional nanomicelleplexes. The nanomicelleplexes exhibited spherical shape, possessed a positively charged surface with a zeta potential of +22.5mV and had a desirable and uniform particle size of 187nm. In vitro release studies revealed that the nanomicelleplexes could release DOX and Bcl-2 siRNA in a reduction and pH dual-sensitive manner and the payload release was significantly enhanced in a reductive acidic environment mimicking the endosomes/lysosomes of cancer cells compared to under physiology conditions. Furthermore, the release of both DOX and siRNA was found to follow Higuchi kinetic

  9. Coenzyme Q10 Protects Hippocampal Neurons against Ischemia/ Reperfusion Injury via Modulation of BAX/Bcl-2 Expression

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    Mohammad Zamani

    2012-09-01

    Full Text Available Introduction: Preliminary studies have con.rmed reduction in cell death following treatment with antioxidants. According to this .nding we study the relationship between consumption of CoQ10 and expression of Bax and Bcl2 in hippocampus following ischemia/reperfusion as proteins involved in cell programmed death or apoptosis. Methods: We studied the protective role of CoQ10 against ischemia-reperfusion. Experimental design includes four groups:  intact, ischemic control, sham control and treatment group with CoQ10. The mice were pre-treated with CoQ10 for a week, then ischemia was induced by common carotid artery ligation and following the reduction in in.ammation (a week the mice was treated with CoQ10.  Nissl staining was applied for counting the necrotic cells of hippocampus and the western blot was performed to measure the Bax and Bcl2 expression.Results: Cell death was signi.cantly lower when mice were treated with CoQ10. Bax expression was signi.cantly high in the ischemic group but low in the treatment group, and the bcl2 expression was lower in the ischemic group than the treatment and the vehicle groups.Discussion: Ischemia for 15 minutes induced cell death in hippocampus with more potent effect on CA1. CoQ10 intake signi.cantly reduced cell death and prevented the expression of Bax while inducing an increase in expression of bcl2.

  10. Coenzyme Q10 Protects Hippocampal Neurons Against Ischemia/Reperfusion Injury via Modulation of BAX/Bcl-2 Expression

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    M Zamani

    2012-12-01

    Full Text Available Introduction : Preliminary studies confirmed reduction in cell death following treatment with antioxidants. According to this finding we study the relationship between consumption of CoQ10 and expression of bax and bcl2 in hippocampus following ischemia/reperfusion as proteins involved in cell programmed death or apoptosis.Material & methods : We studied the protective role of CoQ10 against Ischemia-Reperfusion. Experimental design includes four groups: intact, ischemic control, sham control and treatment groups with CoQ10. The mice treated with CoQ10 as Pre - Treatment for a week. Then, ischemia induced by common carotid artery ligation and following the reduction in inflammation (a week the mice post-treated with CoQ10.Nissl staining applied to counting necrotic cells of hippocampus and the western blotting performed to measurement the bax and bcl2 expression.Results :. Cell death was significantly lower when mice treated with CoQ10. Bax expression was significantly high in ischemic group but in treatment group was less and reversely the bcl2 expression in ischemic group was lower than treatment and vehicle groups.Conclusion : Ischemia for 15 minutes induced cell death in hippocampus with more potent effect on CA1. CoQ10 intake significantly reduced cell death and prevented the expression of bax while inducing an increase in expression of bcl2.

  11. Decreased Expression of Beclin 1 Correlates Closely with Bcl-xL Expression and Poor Prognosis of Ovarian Carcinoma

    Science.gov (United States)

    Rao, Hui-Lan; Yang, Guo-Fen; Kung, Hsiang-Fu; Zhu, Xiao-Feng; Zeng, Yi-Xin; Cai, Mu-Yan; Xie, Dan

    2013-01-01

    Background It has been suggested that autophagy-related Beclin 1 plays a critical role in the regulation of tumor development and/or progression, but its prognostic significance and relationship with Bcl-xL expression in ovarian carcinoma are unclear. Methodology/Principal Findings In the present study, the methods of Western blotting and immunohistochemistry (IHC) were utilized to investigate the expression status of Beclin 1 and Bcl-xL in fresh ovarian tissues and paraffin-embedded epithelial ovarian tumor tissues. Decreased expression of Beclin 1 was examined by IHC in 8.3% of normal ovaries, in 15.4% of cystadenomas, in 20.0% of borderline tumors, and in 55.6% of ovarian carcinomas, respectively. In ovarian carcinomas, decreased expression of Beclin 1 was correlated closely with ascending histological grade, later pT/pN/pM status and/or advanced clinical stage (Povarian carcinoma patients (Povarian carcinoma cohort, and combined analysis further showed that the low Beclin 1/high Bcl-xL group had the lowest survival rate. Conclusions/Significance Our findings suggest that Beclin 1 expression, as examined by IHC, could be served as an additional tool in identifying ovarian carcinoma patients at risk of tumor progression, and predicting patient survival in ovarian carcinomas with increased expression of Bcl-xL. PMID:23573264

  12. Allyl isothiocyanate arrests cancer cells in mitosis, and mitotic arrest in turn leads to apoptosis via Bcl-2 protein phosphorylation.

    Science.gov (United States)

    Geng, Feng; Tang, Li; Li, Yun; Yang, Lu; Choi, Kyoung-Soo; Kazim, A Latif; Zhang, Yuesheng

    2011-09-16

    Allyl isothiocyanate (AITC) occurs in many commonly consumed cruciferous vegetables and exhibits significant anti-cancer activities. Available data suggest that it is particularly promising for bladder cancer prevention and/or treatment. Here, we show that AITC arrests human bladder cancer cells in mitosis and also induces apoptosis. Mitotic arrest by AITC was associated with increased ubiquitination and degradation of α- and β-tubulin. AITC directly binds to multiple cysteine residues of the tubulins. AITC induced mitochondrion-mediated apoptosis, as shown by cytochrome c release from mitochondria to cytoplasm, activation of caspase-9 and caspase-3, and formation of TUNEL-positive cells. Inhibition of caspase-9 blocked AITC-induced apoptosis. Moreover, we found that apoptosis induction by AITC depended entirely on mitotic arrest and was mediated via Bcl-2 phosphorylation at Ser-70. Pre-arresting cells in G(1) phase by hydroxyurea abrogated both AITC-induced mitotic arrest and Bcl-2 phosphorylation. Overexpression of a Bcl-2 mutant prevented AITC from inducing apoptosis. We further showed that AITC-induced Bcl-2 phosphorylation was caused by c-Jun N-terminal kinase (JNK), and AITC activates JNK. Taken together, this study has revealed a novel anticancer mechanism of a phytochemical that is commonly present in human diet.

  13. Enhanced dopaminergic differentiation of human neural stem cells by synergistic effect of Bcl-xL and reduced oxygen tension

    DEFF Research Database (Denmark)

    Krabbe, Christina; Courtois, Elise; Jensen, Pia

    2009-01-01

    Neural stem cells constitute a promising source of cells for transplantation in Parkinson's disease, but a protocol for controlled dopaminergic differentiation is not yet available. Here we investigated the effect of the anti-apoptotic protein Bcl-x(L) and oxygen tension on dopaminergic different......Neural stem cells constitute a promising source of cells for transplantation in Parkinson's disease, but a protocol for controlled dopaminergic differentiation is not yet available. Here we investigated the effect of the anti-apoptotic protein Bcl-x(L) and oxygen tension on dopaminergic...... differentiation and survival of a human ventral mesencephalic stem cell line (hVM1). hVM1 cells and a Bcl-x(L) over-expressing subline (hVMbcl-x(L)) were differentiated by sequential treatment with fibroblast growth factor-8, forskolin, sonic hedgehog, and glial cell line-derived neurotrophic factor. After 10......-PCR-analysis revealed expression of several dopaminergic markers besides of TH just as dopamine was detected in the culture medium by HPLC analysis. Although Bcl-x(L)-over-expression reduced cell death in the cultures, it did not alter the relative content of GABAergic, neurons, while the content of astroglial cells...

  14. Bcl-2 protects against apoptosis induced by antimycin A and bongkrekic acid without restoring cellular ATP levels.

    NARCIS (Netherlands)

    Graaf, A.O. de; Meijerink, J.P.P.; Heuvel, L.P.W.J. van den; Abreu, R.A. de; Witte, T.J.M. de; Jansen, J.H.; Smeitink, J.A.M.

    2002-01-01

    Several studies indicate that mitochondrial ATP production as well as ADP/ATP exchange across mitochondrial membranes are impaired during apoptosis. We investigated whether Bcl-2 could protect against cell death under conditions in which ATP metabolism is inhibited. Inhibition of ATP production

  15. Overexpression of the transcriptional repressor complex BCL-6/BCoR leads to nuclear aggregates distinct from classical aggresomes.

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    Elisabeth Buchberger

    Full Text Available Nuclear inclusions of aggregated proteins have primarily been characterized for molecules with aberrant poly-glutamine repeats and for mutated or structurally altered proteins. They were termed "nuclear aggresomes" and misfolding was shown to promote association with molecular chaperones and proteasomes. Here, we report that two components of a transcriptional repressor complex (BCL-6 and BCoR of wildtype amino acid sequence can independently or jointly induce the formation of nuclear aggregates when overexpressed. The observation that the majority of cells rapidly downregulate BCL-6/BCoR levels, supports the notion that expression of these proteins is under tight control. The inclusions occur when BCL-6/BCoR expression exceeds 150-fold of endogenous levels. They preferentially develop in the nucleus by a gradual increase in aggregate size to form large, spheroid structures which are not associated with heat shock proteins or marked by ubiquitin. In contrast, we find the close association of BCL-6/BCoR inclusions with PML bodies and a reduction in aggregation upon the concomitant overexpression of histone deacetylases or heat shock protein 70. In summary, our data offer a perspective on nuclear aggregates distinct from classical "nuclear aggresomes": Large complexes of spheroid structure can evolve in the nucleus without being marked by the cellular machinery for protein refolding and degradation. However, nuclear proteostasis can be restored by balancing the levels of chaperones.

  16. Bcl-2, Bax, and c-Fos expression correlates to RPE cell apoptosis induced by UV-light and daunorubicin

    DEFF Research Database (Denmark)

    Liang, Y G; Jorgensen, A G; Kaestel, C G

    2000-01-01

    PURPOSE. The aim of this study was to determine the role of Bcl-2, Bcl-X L, Bax, and c-Fos in regulation of apoptosis, induced by ultraviolet-light A (UV-A) and daunorubicin (DNR), in retinal pigment epithelium (RPE) cells grown on bovine extracellular matrix (ECM)-coated or uncoated plastic dishes....... METHODS. Apoptosis in confluent RPE cells cultured on ECM-coated or uncoated dishes was induced by UV-A or DNR. Apoptosis was detected by 7-amino-actinomycin D labeling followed by flow cytometry and by terminal deoxy-transferase mediated X-dUTP nick end labeling (TUNEL). Cellular expression of Bcl-2, Bcl......-X L, Bax, and c-Fos was determined by the use of antibodies and flow cytometry, Western blot analysis, and immunocytochemical staining. RESULTS. Both UV-A and DNR induce apoptosis in human RPE cells in vitro. Human fetal RPE cells grown on ECM-coated dishes were significantly more resistant to UV...

  17. Onco-miR-24 regulates cell growth and apoptosis by targeting BCL2L11 in gastric cancer

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    Haiyang Zhang

    2016-01-01

    Full Text Available ABSTRACT Gastric cancer is one of the most common malignancies worldwide; however, the molecular mechanism in tumorigenesis still needs exploration. BCL2L11 belongs to the BCL-2 family, and acts as a central regulator of the intrinsic apoptotic cascade and mediates cell apoptosis. Although miRNAs have been reported to be involved in each stage of cancer development, the role of miR-24 in GC has not been reported yet. In the present study, miR-24 was found to be up-regulated while the expression of BCL2L11 was inhibited in tumor tissues of GC. Studies from both in vitro and in vivo shown that miR-24 regulates BCL2L11 expression by directly binding with 3′UTR of mRNA, thus promoting cell growth, migration while inhibiting cell apoptosis. Therefore, miR-24 is a novel onco-miRNA that can be potential drug targets for future clinical use.

  18. MYC cytogenetic status correlates with expression and has prognostic significance in patients with MYC/BCL2 protein double-positive diffuse large B-cell lymphoma.

    Science.gov (United States)

    Wang, Xuan Julia; Medeiros, L Jeffrey; Lin, Pei; Yin, C Cameron; Hu, Shimin; Thompson, Mary Ann; Li, Shaoying

    2015-09-01

    MYC/BCL2 double-hit lymphoma (DHL), defined by conventional cytogenetic or fluorescence in situ hybridization (FISH) analysis, and MYC/BCL2 double-positive lymphoma (DPL), defined by immunohistochemistry, are associated with a poor prognosis. However, DHL and DPL are not concordant, and it is unclear whether MYC and BCL2 aberrations have prognostic impact in DPL patients. In a cohort of 135 patients diagnosed with large B-cell lymphoma between 2010 and 2014 in whom MYC/8q24 and BCL2/t(14;18)(q32;q21) statuses were assessed by FISH at diagnosis, we evaluated MYC and BCL2 expression by immunohistochemistry. A total of 54 (40%) cases were positive for MYC and BCL2 supporting DPL. Among them, 19 (35%) had MYC rearrangement including 11 DHLs, 12 (22%) had multiple copies of MYC, 19 had no MYC abnormalities, and in 4 cases FISH analysis failed. BCL2 abnormalities were present in 28/54 (52%) cases (20 rearranged and 8 multiple copies). MYC rearrangement correlated with a significantly worse overall survival in DPL (P0.05). MYC and BCL2 expression by immunohistochemistry correlates with gene status by FISH; however, immunohistochemistry is neither specific nor adequately sensitive to be used as a surrogate for MYC and BCL2 gene status using any cutoff level. In conclusion, MYC rearrangement identifies a subset of patients with DPL who have a significantly worse prognosis. Although immunohistochemical assessment for MYC and BCL2 may be a helpful initial screen to identify higher-risk patients, FISH analysis for MYC remains important for further risk stratification in patients with DPL.

  19. Bcl-2 protein expression is associated with p27 and p53 protein expressions and MIB-1 counts in breast cancer

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    Nishizaki Takashi

    2006-07-01

    Full Text Available Abstract Background Recent experimental studies have shown that Bcl-2, which has been established as a key player in the control of apoptosis, plays a role in regulating the cell cycle and proliferation. The aim of this study was to investigate the relationship between Bcl-2 and p27 protein expression, p53 protein expression and the proliferation activity as defined by the MIB-1 counts. The prognostic implication of Bcl-2 protein expression in relation to p27 and p53 protein expressions and MIB-1 counts for breast cancer was also evaluated. Methods The immunohistochemical expression of Bcl-2 protein was evaluated in a series of 249 invasive ductal carcinomas of the breast, in which p27 and p53 protein expressions and MIB-1 counts had been determined previously. Results The Bcl-2 protein expression was found to be decreased in 105 (42% cases. A decreased Bcl-2 protein expression was significantly correlated with a nuclear grade of III, a negative estrogen receptor, a decreased p27 protein expression, a positive p53 protein expression, positive MIB-1 counts and a positive HER2 protein expression. The incidence of a nuclear grade of III and positive MIB-1 counts increased as the number of abnormal findings of Bcl-2, p27 and p53 protein expressions increased. A univariate analysis indicated a decreased Bcl-2 protein expression to be significantly (p = 0.0089 associated with a worse disease free survival (DFS, while a multivariate analysis indicated the lymph node status and MIB-1 counts to be independently significant prognostic factors for the DFS. Conclusion The Bcl-2 protein expression has a close correlation with p27 and p53 protein expressions and the proliferation activity determined by MIB-1 counts in invasive ductal carcinoma of the breast. The prognostic value of Bcl-2 as well as p27 and p53 protein expressions was dependent on the proliferation activity in breast cancer.

  20. Bcl-2 protein expression is associated with p27 and p53 protein expressions and MIB-1 counts in breast cancer

    International Nuclear Information System (INIS)

    Tsutsui, Shinichi; Yasuda, Kazuhiro; Suzuki, Kosuke; Takeuchi, Hideya; Nishizaki, Takashi; Higashi, Hidefumi; Era, Shoichi

    2006-01-01

    Recent experimental studies have shown that Bcl-2, which has been established as a key player in the control of apoptosis, plays a role in regulating the cell cycle and proliferation. The aim of this study was to investigate the relationship between Bcl-2 and p27 protein expression, p53 protein expression and the proliferation activity as defined by the MIB-1 counts. The prognostic implication of Bcl-2 protein expression in relation to p27 and p53 protein expressions and MIB-1 counts for breast cancer was also evaluated. The immunohistochemical expression of Bcl-2 protein was evaluated in a series of 249 invasive ductal carcinomas of the breast, in which p27 and p53 protein expressions and MIB-1 counts had been determined previously. The Bcl-2 protein expression was found to be decreased in 105 (42%) cases. A decreased Bcl-2 protein expression was significantly correlated with a nuclear grade of III, a negative estrogen receptor, a decreased p27 protein expression, a positive p53 protein expression, positive MIB-1 counts and a positive HER2 protein expression. The incidence of a nuclear grade of III and positive MIB-1 counts increased as the number of abnormal findings of Bcl-2, p27 and p53 protein expressions increased. A univariate analysis indicated a decreased Bcl-2 protein expression to be significantly (p = 0.0089) associated with a worse disease free survival (DFS), while a multivariate analysis indicated the lymph node status and MIB-1 counts to be independently significant prognostic factors for the DFS. The Bcl-2 protein expression has a close correlation with p27 and p53 protein expressions and the proliferation activity determined by MIB-1 counts in invasive ductal carcinoma of the breast. The prognostic value of Bcl-2 as well as p27 and p53 protein expressions was dependent on the proliferation activity in breast cancer

  1. The sensitivity of diffuse large B-cell lymphoma cell lines to histone deacetylase inhibitor-induced apoptosis is modulated by BCL-2 family protein activity.

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    Ryan C Thompson

    Full Text Available BACKGROUND: Diffuse large B-cell lymphoma (DLBCL is a genetically heterogeneous disease and this variation can often be used to explain the response of individual patients to chemotherapy. One cancer therapeutic approach currently in clinical trials uses histone deacetylase inhibitors (HDACi's as monotherapy or in combination with other agents. METHODOLOGY/PRINCIPAL FINDINGS: We have used a variety of cell-based and molecular/biochemical assays to show that two pan-HDAC inhibitors, trichostatin A and vorinostat, induce apoptosis in seven of eight human DLBCL cell lines. Consistent with previous reports implicating the BCL-2 family in regulating HDACi-induced apoptosis, ectopic over-expression of anti-apoptotic proteins BCL-2 and BCL-XL or pro-apoptotic protein BIM in these cell lines conferred further resistance or sensitivity, respectively, to HDACi treatment. Additionally, BCL-2 family antgonist ABT-737 increased the sensitivity of several DLBCL cell lines to vorinostat-induced apoptosis, including one cell line (SUDHL6 that is resistant to vorinostat alone. Moreover, two variants of the HDACi-sensitive SUDHL4 cell line that have decreased sensitivity to vorinostat showed up-regulation of BCL-2 family anti-apoptotic proteins such as BCL-XL and MCL-1, as well as decreased sensitivity to ABT-737. These results suggest that the regulation and overall balance of anti- to pro-apoptotic BCL-2 family protein expression is important in defining the sensitivity of DLBCL to HDACi-induced apoptosis. However, the sensitivity of DLBCL cell lines to HDACi treatment does not correlate with expression of any individual BCL-2 family member. CONCLUSIONS/SIGNIFICANCE: These studies indicate that the sensitivity of DLBCL to treatment with HDACi's is dependent on the complex regulation of BCL-2 family members and that BCL-2 antagonists may enhance the response of a subset of DLBCL patients to HDACi treatment.

  2. Atherosclerosis-Associated Endothelial Cell Apoptosis by MiR-429-Mediated Down Regulation of Bcl-2

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    Tao Zhang

    2015-10-01

    Full Text Available Background/Aims: Endothelial cell injury and subsequent apoptosis play a key role in the development and pathogenesis of atherosclerosis, which is hallmarked by dysregulated lipid homeostasis, aberrant immunity and inflammation, and plaque-instability-associated coronary occlusion. Nevertheless, our understanding of the mechanisms underlying endothelial cell apoptosis is still limited. MicroRNA-429 (miR-29 is a known cancer suppressor that promotes cancer cell apoptosis. However, it is unknown whether miR-429 may be involved in the development of atherosclerosis through similar mechanisms. We addressed these questions in the current study. Methods: We examined the levels of endothelial cell apoptosis in ApoE (-/- mice suppled with high-fat diet (HFD, a mouse model for atherosclerosis (simplified as HFD mice. We analyzed the levels of anti-apoptotic protein Bcl-2 and the levels of miR-429 in the purified CD31+ endothelial cells from mouse aorta. Prediction of the binding between miR-429 and 3'-UTR of Bcl-2 mRNA was performed by bioinformatics analyses and confirmed by a dual luciferase reporter assay. The effects of miR-429 were further analyzed in an in vitro model using oxidized low-density lipoprotein (ox-LDL-treated human aortic endothelial cells (HAECs. Results: HFD mice developed atherosclerosis in 12 weeks, while the control ApoE (-/- mice that had received normal diet (simplified as NOR mice did not. HFD mice had significantly lower percentage of endothelial cells and significantly higher percentage of mesenchymal cells in the aorta than NOR mice. Significantly higher levels of endothelial cell apoptosis were detected in HFD mice, resulting from decreases in Bcl-2 protein, but not mRNA. The decreases in Bcl-2 in endothelial cells were due to increased levels of miR-429, which suppressed the translation of Bcl-2 mRNA via 3'-UTR binding. These in vivo findings were reproduced in vitro on ox-LDL-treated HAECs. Conclusion: Atherosclerosis

  3. ATP promotes cell survival via regulation of cytosolic [Ca2+] and Bcl-2/Bax ratio in lung cancer cells

    Science.gov (United States)

    Song, Shanshan; Jacobson, Krista N.; McDermott, Kimberly M.; Reddy, Sekhar P.; Cress, Anne E.; Tang, Haiyang; Dudek, Steven M.; Black, Stephen M.; Garcia, Joe G. N.; Makino, Ayako

    2015-01-01

    Adenosine triphosphate (ATP) is a ubiquitous extracellular messenger elevated in the tumor microenvironment. ATP regulates cell functions by acting on purinergic receptors (P2X and P2Y) and activating a series of intracellular signaling pathways. We examined ATP-induced Ca2+ signaling and its effects on antiapoptotic (Bcl-2) and proapoptotic (Bax) proteins in normal human airway epithelial cells and lung cancer cells. Lung cancer cells exhibited two phases (transient and plateau phases) of increase in cytosolic [Ca2+] ([Ca2+]cyt) caused by ATP, while only the transient phase was observed in normal cells. Removal of extracellular Ca2+ eliminated the plateau phase increase of [Ca2+]cyt in lung cancer cells, indicating that the plateau phase of [Ca2+]cyt increase is due to Ca2+ influx. The distribution of P2X (P2X1-7) and P2Y (P2Y1, P2Y2, P2Y4, P2Y6, P2Y11) receptors was different between lung cancer cells and normal cells. Proapoptotic P2X7 was nearly undetectable in lung cancer cells, which may explain why lung cancer cells showed decreased cytotoxicity when treated with high concentration of ATP. The Bcl-2/Bax ratio was increased in lung cancer cells following treatment with ATP; however, the antiapoptotic protein Bcl-2 demonstrated more sensitivity to ATP than proapoptotic protein Bax. Decreasing extracellular Ca2+ or chelating intracellular Ca2+ with BAPTA-AM significantly inhibited ATP-induced increase in Bcl-2/Bax ratio, indicating that a rise in [Ca2+]cyt through Ca2+ influx is the critical mediator for ATP-mediated increase in Bcl-2/Bax ratio. Therefore, despite high ATP levels in the tumor microenvironment, which would induce cell apoptosis in normal cells, the decreased P2X7 and elevated Bcl-2/Bax ratio in lung cancer cells may enable tumor cells to survive. Increasing the Bcl-2/Bax ratio by exposure to high extracellular ATP may, therefore, be an important selective pressure promoting transformation and cancer progression. PMID:26491047

  4. ATP promotes cell survival via regulation of cytosolic [Ca2+] and Bcl-2/Bax ratio in lung cancer cells.

    Science.gov (United States)

    Song, Shanshan; Jacobson, Krista N; McDermott, Kimberly M; Reddy, Sekhar P; Cress, Anne E; Tang, Haiyang; Dudek, Steven M; Black, Stephen M; Garcia, Joe G N; Makino, Ayako; Yuan, Jason X-J

    2016-01-15

    Adenosine triphosphate (ATP) is a ubiquitous extracellular messenger elevated in the tumor microenvironment. ATP regulates cell functions by acting on purinergic receptors (P2X and P2Y) and activating a series of intracellular signaling pathways. We examined ATP-induced Ca(2+) signaling and its effects on antiapoptotic (Bcl-2) and proapoptotic (Bax) proteins in normal human airway epithelial cells and lung cancer cells. Lung cancer cells exhibited two phases (transient and plateau phases) of increase in cytosolic [Ca(2+)] ([Ca(2+)]cyt) caused by ATP, while only the transient phase was observed in normal cells. Removal of extracellular Ca(2+) eliminated the plateau phase increase of [Ca(2+)]cyt in lung cancer cells, indicating that the plateau phase of [Ca(2+)]cyt increase is due to Ca(2+) influx. The distribution of P2X (P2X1-7) and P2Y (P2Y1, P2Y2, P2Y4, P2Y6, P2Y11) receptors was different between lung cancer cells and normal cells. Proapoptotic P2X7 was nearly undetectable in lung cancer cells, which may explain why lung cancer cells showed decreased cytotoxicity when treated with high concentration of ATP. The Bcl-2/Bax ratio was increased in lung cancer cells following treatment with ATP; however, the antiapoptotic protein Bcl-2 demonstrated more sensitivity to ATP than proapoptotic protein Bax. Decreasing extracellular Ca(2+) or chelating intracellular Ca(2+) with BAPTA-AM significantly inhibited ATP-induced increase in Bcl-2/Bax ratio, indicating that a rise in [Ca(2+)]cyt through Ca(2+) influx is the critical mediator for ATP-mediated increase in Bcl-2/Bax ratio. Therefore, despite high ATP levels in the tumor microenvironment, which would induce cell apoptosis in normal cells, the decreased P2X7 and elevated Bcl-2/Bax ratio in lung cancer cells may enable tumor cells to survive. Increasing the Bcl-2/Bax ratio by exposure to high extracellular ATP may, therefore, be an important selective pressure promoting transformation and cancer progression. Copyright

  5. BCL2 and keratin 5 define the uterine-cervix-isthmus junction, a transition between endocervical and tubal-like epithelium.

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    Hoogduin, Klaas J; Hopman, Anton N H; Ramaekers, Frans C S; McCluggage, W Glenn; Smedts, Frank

    2013-01-01

    A clearcut definition of the transition from the cervix to the lower uterine segment is lacking. We therefore evaluated the location of the anatomic border between the cervix and the uterine corpus. Using both morphometry and immunohistochemisty, we examined the epithelial and stromal cell types in this transition zone. In 26 patients, longitudinal sections from the cervix uteri up to the fundus uteri were paraffin embedded and immunohistochemically stained for BCL2, keratin 5, Ki-67, CD10, and CD34. Examination of the slides resulted in the identification of a junctional zone in the cranial portion of the cervix, which is characterized by a usually abrupt morphologic and immunohistochemical transition from an endocervical-type mucinous epithelium to a ciliated tubal-like epithelium and a slow transition in stromal marker expression patterns. This epithelial transition was characterized by its intense keratin 5 and BCL2 staining with accompanying Ki-67 expression in the tubal-like epithelium, whereas the endocervical epithelium was largely negative for these markers. CD10 expression was usually quite intense directly around endocervical invaginations, but the remaining stroma was negative. Toward the endometrial cavity, expression increased and endometrial stroma displayed full thickness expression for CD10. CD34 showed a reverse pattern to CD10, with moderate expression in the endocervical stroma, which disappeared in the endometrial stoma. The immunohistochemical identification of this transition may allow a more objective determination of the extension of endometrial carcinoma into the cervix in cases that are morphologically problematic. Furthermore, as ciliated tubal-like epithelium is invariably found cranial to the uterine-cervix-isthmus junction, a diagnosis of tubal metaplasia should not be made in this region and tubal-like epithelium is not indicative of a metaplastic process.

  6. Pokemon reduces Bcl-2 expression through NF-κ Bp65: A possible mechanism of hepatocellular carcinoma.

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    Zhao, Xinkai; Ning, Qiaoming; Sun, Xiaoning; Tian, De'an

    2011-06-01

    To investigate the relationship among Pokemon, NF-κ B p65 and Bcl-2 in hepatoma cells. HCC cell HepG2, SMMC7721 and human fetal liver cell line LO2 cells were used, and expression of Pokemon, NF-κ B p65 and Bcl-2 in three cells were detected by real-time PCR and western blot. Then siRNA of Pokemon was applied to inhibit the expression of Pokemon and NF-κ B p65 and apoptotic rate was determined by flow cytometric analysis. Expressions of Pokemon, NF-κ B p65 and Bcl-2 in human hepatoma cell HepG2, SMMC7721 expression were significantly higher than those in human embryonic stem cells LO2. siRNA of Pokemon inhibited the expression of Pokemon, NF-κ B p65 and Bcl-2 in liver cancer cells, and significantly increased apoptosis of liver cells. While siRNA of NF-κ B p65 inhibited the expression of NF-κ B p65 and Bcl-2, but Pokemon expression in hepatoma cells had no significant change. The proto-oncogene Pokemon can inhibit P14ARF by specific transcription regulation of cell cycle and can induce tumors. In addition, Pokemon can regulate NF-κ B p65 through the expression of apoptosis repressor, and promote the development of liver cancer. It suggests signal network in the liver include the regulation of new non-classical NF-κ B regulatory pathway. Copyright © 2011 Hainan Medical College. Published by Elsevier B.V. All rights reserved.

  7. Carrageenan-Induced Colonic Inflammation Is Reduced in Bcl10 Null Mice and Increased in IL-10-Deficient Mice

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    Sumit Bhattacharyya

    2013-01-01

    Full Text Available The common food additive carrageenan is a known activator of inflammation in mammalian tissues and stimulates both the canonical and noncanonical pathways of NF-κB activation. Exposure to low concentrations of carrageenan (10 μg/mL in the water supply has produced glucose intolerance, insulin resistance, and impaired insulin signaling in C57BL/6 mice. B-cell leukemia/lymphoma 10 (Bcl10 is a mediator of inflammatory signals from Toll-like receptor (TLR 4 in myeloid and epithelial cells. Since the TLR4 signaling pathway is activated in diabetes and by carrageenan, we addressed systemic and intestinal inflammatory responses following carrageenan exposure in Bcl10 wild type, heterozygous, and null mice. Fecal calprotectin and circulating keratinocyte chemokine (KC, nuclear RelA and RelB, phospho(Thr559-NF-κB-inducing kinase (NIK, and phospho(Ser36-IκBα in the colonic epithelial cells were significantly less (P<0.001 in the carrageenan-treated Bcl10 null mice than in controls. IL-10-deficient mice exposed to carrageenan in a germ-free environment showed an increase in activation of the canonical pathway of NF-κB (RelA activation, but without increase in RelB or phospho-Bcl10, and exogenous IL-10 inhibited only the canonical pathway of NF-κB activation in cultured colonic cells. These findings demonstrate a Bcl10 requirement for maximum development of carrageenan-induced inflammation and lack of complete suppression by IL-10 of carrageenan-induced inflammation.

  8. PSAP induces a unique Apaf-1 and Smac-dependent mitochondrial apoptotic pathway independent of Bcl-2 family proteins.

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    Li, Ting; Zeng, Linlin; Gao, Wei; Cui, Mei-Zhen; Fu, Xueqi; Xu, Xuemin

    2013-03-01

    Presenilin-associated protein (PSAP) has been identified as a mitochondrial proapoptotic protein. However, the mechanism by which PSAP induces apoptosis remains unknown. To this end, we have established an inducible expression system. Using this system, we have examined the roles of B-cell lymphoma 2 (Bcl-2) family proteins, cytochrome c, Smac (Smac/Diablo, second mitochondria-derived activator of caspases/direct IAP binding protein with low PI), and Apaf-1 (apoptotic protease-activating factor) in PSAP-induced apoptosis. Our results demonstrate that knockdown of Apaf-1 abolished PSAP-induced caspase activation and poly(ADP ribose) polymerase (PARP) cleavage, indicating that the apoptosome formation triggered by cytochrome c is crucial for PSAP-induced apoptosis. Our data also demonstrate that knockdown of Smac abolished PSAP-induced caspase activation and PARP cleavage, indicating that, in addition to Apaf-1 or apoptosome formation, Smac is also essential for PSAP-induced apoptosis. However, interestingly, our data demonstrate that overexpression of Bcl-2 and Bcl-xL did not protect cells from PSAP-induced apoptosis, and that knockdown of Bid, Bax, and Bak had no effect on PSAP-induced cytochrome c and Smac release, indicating that PSAP-induced apoptosis is not regulated by Bcl-2 family proteins. These results strongly suggest that PSAP evokes mitochondrial apoptotic cascades via a novel mechanism that is not regulated by Bcl-2 family proteins, but that both the formation of cytochrome c-Apaf-1 apoptosome and the presence of Smac are absolutely required for PSAP-induced apoptosis. Copyright © 2012 Elsevier B.V. All rights reserved.

  9. Caspase induction and BCL2 inhibition in human adipose tissue: a potential relationship with insulin signaling alteration.

    Science.gov (United States)

    Tinahones, Francisco José; Coín Aragüez, Leticia; Murri, Mora; Oliva Olivera, Wilfredo; Mayas Torres, María Dolores; Barbarroja, Nuria; Gomez Huelgas, Ricardo; Malagón, Maria M; El Bekay, Rajaa

    2013-03-01

    Cell death determines the onset of obesity and associated insulin resistance. Here, we analyze the relationship among obesity, adipose tissue apoptosis, and insulin signaling. The expression levels of initiator (CASP8/9) and effector (CASP3/7) caspases as well as antiapoptotic B-cell lymphoma (BCL)2 and inflammatory markers were assessed in visceral (VAT) and subcutaneous (SAT) adipose tissue from patients with different degrees of obesity and without insulin resistance or diabetes. Adipose tissue explants from lean subjects were cultured with TNF-α or IL-6, and the expression of apoptotic and insulin signaling components was analyzed and compared with basal expression levels in morbidly obese subjects. SAT and VAT exhibited increased CASP3/7 and CASP8/9 expression levels and decreased BCL2 expression with BMI increase. These changes were accompanied by increased inflammatory cytokine mRNA levels and macrophage infiltration markers. In obese subjects, CASP3/7 activation and BCL2 downregulation correlated with the IRS-1/2-expression levels. Expression levels of caspases, BCL2, p21, p53, IRS-1/2, GLUT4, protein tyrosine phosphatase 1B, and leukocyte antigen-related phosphatase in TNF-α- or IL-6-treated explants from lean subjects were comparable with those found in adipose tissue samples from morbidly obese subjects. These insulin component expression levels were reverted with CASP3/7 inhibition in these TNF-α- or IL-6-treated explants. Body fat mass increase is associated with CASP3/7 and BCL2 expression in adipose tissue. Moreover, this proapoptotic state correlated with insulin signaling, suggesting its potential contribution to the development of insulin resistance.

  10. Can Bcl-XL expression predict the radio sensitivity of Bilharzial-related squamous bladder carcinoma? a prospective comparative study

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    Kamel Nermen A

    2011-01-01

    Full Text Available Abstract Background Local pelvic recurrence after radical cystectomy for muscle invasive bilharzial related squamous cell carcinoma accounts for 75% of treatment failures even in organ confined tumors. Despite the proven value of lymphadenectomy, up to 60% of patients undergoing cystectomy do not have it. These factors are in favor of adjuvant radiotherapy reevaluation. objectives: to evaluate the effect of adjuvant radiotherapy on disease free survival in muscle invasive bilharzial related squamous cell carcinoma of the urinary bladder and to test the predictability of radio-sensitivity using the anti apoptotic protein Bcl-XL. Methods The study prospectively included 71 patients, (47 males, 24 females with muscle invasive bilharzial related squamous cell carcinoma of the bladder (Stage pT2a-T3N0-N3M0 who underwent radical cystectomy in Assiut university hospitals between January 2005 and December 2006. Thirty eight patients received adjuvant radiotherapy to the pelvis in the dose of 50Gy/25 fractions/5 weeks (Group 1, while 33 patients did not receive adjuvant radiotherapy (group 2. Immunohistochemical characterization for bcl-xL expression was done. Follow up was done every 3 months for 12 to 36 months with a mean of 16 ± 10 months. All data were analyzed using SPSS version 16. Three years cumulative disease free survival was calculated and adjusted to Bcl-XL expression and side effects of the treatment were recorded. Results The disease free cumulative survival was 48% for group 1 and 29% for group 2 (log rank p value 0.03. The multivariate predictors of tumor recurrence were the positive Bcl-XL expression (odd ratio 41.1, 95% CI 8.4 - 102.3, p Conclusions Adjuvant radiotherapy for muscle invasive bilharzial related squamous cell carcinoma of the urinary bladder has potential effectiveness and minor side effects. Moreover, Bcl-XL expression is a valuable tool for predicting those who might not respond to this adjuvant treatment.

  11. The effect of AT1 receptor blockade on bax and bcl-2 expression in bleomycin-induced pulmonary fibrosis

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    L Safaeian

    2009-03-01

    Full Text Available ABSTRACT Background and the purpose of the study: Recent studies have indicated the role of apoptosis and angiotensin in the pathogenesis of bleomycin induced-pulmonary fibrosis. Losartan, an angiotensin type 1 receptor (AT1R antagonist, has ameliorated apoptosis and fibrosis from bleomycin. In this study, alterations in the expression of apoptosis-regulatory genes (bcl-2 and bax were investigated in different cells of lung tissue of mice treated with bleomycin in the presence of losartan. Methods: Losartan (10 mg/kg, i.p. was given to mice two days before administration of bleomycin (3 U/kg and throughout the test period. After two weeks, lung tissues of mice were evaluated for fibrosis by biochemical measurement of collagen deposition and semiquantitative analysis of pathological changes of the lung. The expression of bcl-2 and bax was assessed by immunohistochemical assay using biotin-streptavidin staining method on paraffin-embedded lung tissues. Results and major conclusion: Pre-treatment with losartan significantly (P < 0.05 reduced the increase in lung collagen content and also inhibited the histological changes induced by bleomycin. Immunohistochemical studies showed that losartan significantly (P < 0.05 reduced the bax/bcl-2 expression ratio in the alveolar epithelial cells, lymphocytes, macrophages and interstitial myofibroblasts. Losartan also inhibited the bcl-2 upregulation which was educed by bleomycin in neutrophils. By reduction of bax/bcl-2 ratio as a determinant of susceptibility of a cell to apoptosis, losartan exerted protective effects on the alveolar epithelial cells that may be important in the amelioration of pulmonary fibrosis. These results may help to better understanding of the role of angiotensin II and apoptosis in pulmonary fibrosis.

  12. The involvement of Bcl-2 family proteins in AKT-regulated cell survival in cisplatin resistant epithelial ovarian cancer.

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    Dai, Yan; Jin, Shiguang; Li, Xueping; Wang, Daxin

    2017-01-03

    Many studies involving patients with cisplatin-resistant ovarian cancer have shown that AKT activation leads to inhibition of apoptosis. The aim of this study was to examine the potential involvement of the Bcl-2 family proteins in AKT-regulated cell survival in response to cisplatin treatment. Cisplatin-sensitive (PEO1) and cisplatin-resistant (PEO4) cells were taken from ascites of patients with ovarian cancer before cisplatin treatment and after development of chemoresistance. It was found that cisplatin treatment activated the AKT signaling pathway and promoted cell proliferation in cisplatin-resistant EOC cells. When AKT was transfected into nucleus of cisplatin-resistant ovarian cancer cells, DNA-PK was phosphorylated at S473. The activated AKT (pAKT-S473) in these cells inhibited the death signal induced by cisplatin thereby inhibiting cisplatin-mediated apoptosis. Results from this study showed that the combination of cisplatin, DNA-PK inhibitor NU7441, and AKT inhibitor TCN can overcome drug resistance, increase apoptosis, and re-sensitize PEO4 cells to cisplatin treatment. A decrease in apoptotic activity was seen in PEO4 cells when Bad was downregulated by siRNA, which indicated that Bad promotes apoptosis in PEO4 cells. Use of the Bcl-2 inhibitor ABT-737 showed that ABT-737 binds to Bcl-2 but not Mcl-1 and releases Bax/Bak which leads to cell apoptosis. The combination of ABT-737 and cisplatin leads to a significant increase in the death of PEO1 and PEO4 cells. All together, these results indicate that Bcl-2 family proteins are regulators of drug resistance. The combination of cisplatin and Bcl-2 family protein inhibitor could be a strategy for the treatment of cisplatin-resistant ovarian cancer.

  13. Decreased expression of Beclin 1 correlates closely with Bcl-xL expression and poor prognosis of ovarian carcinoma.

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    Huan-Xin Lin

    Full Text Available It has been suggested that autophagy-related Beclin 1 plays a critical role in the regulation of tumor development and/or progression, but its prognostic significance and relationship with Bcl-xL expression in ovarian carcinoma are unclear.In the present study, the methods of Western blotting and immunohistochemistry (IHC were utilized to investigate the expression status of Beclin 1 and Bcl-xL in fresh ovarian tissues and paraffin-embedded epithelial ovarian tumor tissues. Decreased expression of Beclin 1 was examined by IHC in 8.3% of normal ovaries, in 15.4% of cystadenomas, in 20.0% of borderline tumors, and in 55.6% of ovarian carcinomas, respectively. In ovarian carcinomas, decreased expression of Beclin 1 was correlated closely with ascending histological grade, later pT/pN/pM status and/or advanced clinical stage (P<0.05. In univariate survival analysis, a highly significant association between low-expressed Beclin 1 and shortened patient survival was evaluated in ovarian carcinoma patients (P<0.01, and Beclin 1 expression was an independent prognostic factor as evidenced by multivariate analysis (P = 0.013. In addition, decreased expression of Beclin 1 was inversely correlated with altered expression of Bcl-xL in ovarian carcinoma cohort, and combined analysis further showed that the low Beclin 1/high Bcl-xL group had the lowest survival rate.Our findings suggest that Beclin 1 expression, as examined by IHC, could be served as an additional tool in identifying ovarian carcinoma patients at risk of tumor progression, and predicting patient survival in ovarian carcinomas with increased expression of Bcl-xL.

  14. Knock-down of NDRG2 sensitizes cervical cancer Hela cells to cisplatin through suppressing Bcl-2 expression

    International Nuclear Information System (INIS)

    Liu, Junye; Guo, Guozhen; Yang, Le; Zhang, Jian; Zhang, Jing; Chen, Yongbin; Li, Kangchu; Li, Yurong; Li, Yan; Yao, Libo

    2012-01-01

    NDRG2, a member of N-Myc downstream regulated gene family, plays some roles in cellular stress, cell differentiation and tumor suppression. We have found that NDRG2 expression in cervical cancer Hela cells increases significantly upon stimulation with cisplatin, the most popular chemotherapeutic agent currently used for the treatment of advanced cervical cancer. This interesting phenomenon drove us to evaluate the role of NDRG2 in chemosensitivity of Hela cells. In the present study, RNA interference was employed to down-regulate NDRG2 expression in Hela cells. RT-PCR and Western blot were used to detect expression of NDRG2, Bcl-2 and Bax in cancer cells. Real-time PCR was applied to detect miR-15b and miR-16 expression levels. Drug sensitivity was determined with MTT assay. Cell cloning efficiency was evaluated by Colony-forming assay. Apoptotic cells were detected with annexin V staining and flow cytometry. In vitro drug sensitivity assay revealed that suppression of NDRG2 could sensitize Hela cells to cisplatin. Down-regulation of NDRG2 didn’t influence the colony-forming ability but promoted cisplatin-induced apoptosis of Hela cells. Inhibition of NDRG2 in Hela cells was accompanied by decreased Bcl-2 protein level. However, Bcl-2 mRNA level was not changed in Hela cells with down-regulation of NDRG2. Further study indicated that miR-15b and miR-16, two microRNAs targetting Bcl-2, were significantly up-regulated in NDRG2-suppressed Hela cells. These data suggested that down-regulation of NDRG2 could enhance sensitivity of Hela cells to cisplatin through inhibiting Bcl-2 protein expression, which might be mediated by up-regulating miR-15b and miR-16

  15. Expression of the apoptosis-related genes BCL-2 and BAD in human breast carcinoma and their associated relationship with chemosensitivity

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    Fan Yuan-ming

    2010-08-01

    Full Text Available Abstract Objective To evaluate the expression of BCL-2 and BAD genes in tissues of breast carcinoma and investigate the relationship between the expression of BCL-2 and BAD in breast cancer cells with chemosensitivity. Methods Immunohistochemical technique was used to detect the expression of BCL-2, BAD in 10 normal breast tissues, 10 breast fibroadenoma tissues, 40 youth human breast carcinoma tissues, 40 menopause human breast carcinoma tissues. And to detect the expression of ER, PR in 80 human breast carcinoma tissues. 20 Surgical samples of breast cancer, diagnosed by pathology, were obtained from The First Affiliated Hospital of Chongqing Medical University. The cancer sample cells were cultured separately in the incubator at 37°C, 5% CO2 in vitro. The rate of inhibition of cancer cells in 4 kinds of anticancer drugs-- Epirubicin Adriamycin (EADM,5-Fluorouracil (5-Fu, Navelbine(NVB and Diaminedichloroplatinum (DDP, were assayed by MTT method. Results The expression of BCL-2, BAD genes in young human breast carcinoma tissues were lower than that in menopause human breast carcinoma tissues (P . There was a negative correlation between the positive expression rate of BCL-2 and histologic grade or the lymph node metastasis (P . There was a positive correlation between the expression rates of BCL-2 and of ER, PR (P . The expression of BAD had no relationship with the expression of ER, PR, histologic grade and the lymph node metastasis(P = NS. Sensitivity rates of 20 breast cancer cells in 0.1 × PPC within 48 h in vitro were 30% EADM,20% 5-Fu,45% NVB and 25% DDP. Respectively, the rate of inhibition of EADM,5- Fu, NVB and DDP were significantly higher in the BCL-2 negative cancer cells than in the BCL-2 positive cancer cells. A negative correlation was found between expression of BCL-2 and chemosensitivity for all the 4 anticancer drugs. The inhibition rates of EADM and NVB were significantly lower in the BAD negative cancer cells than in the

  16. Boron neutron capture therapy induces apoptosis of glioma cells through Bcl-2/Bax

    International Nuclear Information System (INIS)

    Wang, Peng; Zhen, Haining; Jiang, Xinbiao; Zhang, Wei; Cheng, Xin; Guo, Geng; Mao, Xinggang; Zhang, Xiang

    2010-01-01

    Boron neutron capture therapy (BNCT) is an alternative treatment modality for patients with glioma. The aim of this study was to determine whether induction of apoptosis contributes to the main therapeutic efficacy of BNCT and to compare the relative biological effect (RBE) of BNCT, γ-ray and reactor neutron irradiation. The neutron beam was obtained from the Xi'an Pulsed Reactor (XAPR) and γ-rays were obtained from [ 60 Co] γ source of the Fourth Military Medical University (FMMU) in China. Human glioma cells (the U87, U251, and SHG44 cell lines) were irradiated by neutron beams at the XAPR or [ 60 Co] γ-rays at the FMMU with different protocols: Group A included control nonirradiated cells; Group B included cells treated with 4 Gy of [ 60 Co] γ-rays; Group C included cells treated with 8 Gy of [ 60 Co] γ-rays; Group D included cells treated with 4 Gy BPA (p-borono-phenylalanine)-BNCT; Group E included cells treated with 8 Gy BPA-BNCT; Group F included cells irradiated in the reactor for the same treatment period as used for Group D; Group G included cells irradiated in the reactor for the same treatment period as used for Group E; Group H included cells irradiated with 4 Gy in the reactor; and Group I included cells irradiated with 8 Gy in the reactor. Cell survival was determined using the 3-(4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium (MTT) cytotoxicity assay. The morphology of cells was detected by Hoechst33342 staining and transmission electron microscope (TEM). The apoptosis rate was detected by flow cytometer (FCM). The level of Bcl-2 and Bax protein was measured by western blot analysis. Proliferation of U87, U251, and SHG44 cells was much more strongly inhibited by BPA-BNCT than by irradiation with [ 60 Co] γ-rays (P < 0.01). Nuclear condensation was determined using both a fluorescence technique and electron microscopy in all cell lines treated with BPA-BNCT. Furthermore, the cellular apoptotic rates in Group D and Group E treated with

  17. Type A monoamine oxidase is associated with induction of neuroprotective Bcl-2 by rasagiline, an inhibitor of type B monoamine oxidase.

    Science.gov (United States)

    Inaba-Hasegawa, Keiko; Akao, Yukihiro; Maruyama, Wakako; Naoi, Makoto

    2012-04-01

    Rasagiline and (-)deprenyl (selegiline), irreversible type B monoamine oxidase (MAO-B) inhibitors, protect neuronal cells through gene induction of pro-survival Bcl-2 and neurotrophic factors in the cellular models of neurodegenerative disorders. In this paper, the role of MAO in the up-regulation of neuroprotective Bcl-2 gene by these inhibitors was studied using type A MAO (MAO-A) expressing wild SH-SY5Y cells and the transfection-enforced MAO-B overexpressed cells. Rasagiline and (-)deprenyl, and also befloxatone, a reversible MAO-A inhibitor, increased Bcl-2 mRNA and protein in SH-SY5Y cells. Silencing MAO-A expression with short interfering (si) RNA suppressed Bcl-2 induction by rasagiline, but not by (-)deprenyl. MAO-B overexpression inhibited Bcl-2 induction by rasagiline and befloxatone, but did not affect that by (-)deprenyl, suggesting the different mechanisms behind Bcl-2 gene induction by these MAO-B inhibitors. The novel role of MAO-A in Bcl-2 induction by rasagiline is discussed with regard to the molecular mechanism underlying neuroprotection by the MAO inhibitors.

  18. Bcl-xL Genetic Modification Enhanced the Therapeutic Efficacy of Mesenchymal Stem Cell Transplantation in the Treatment of Heart Infarction

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    Xiaodong Xue

    2015-01-01

    Full Text Available Objectives. Low survival rate of mesenchymal stem cells (MSCs severely limited the therapeutic efficacy of cell therapy in the treatment of myocardial infarction (MI. Bcl-xL genetic modification might enhance MSC survival after transplantation. Methods. Adult rat bone marrow MSCs were modified with human Bcl-xL gene (hBcl-xL-MSCs or empty vector (vector-MSCs. MSC apoptosis and paracrine secretions were characterized using flow cytometry, TUNEL, and ELISA in vitro. In vivo, randomized adult rats with MI received myocardial injections of one of the three reagents: hBcl-xL-MSCs, vector-MSCs, or culture medium. Histochemistry, TUNEL, and echocardiography were carried out to evaluate cell engraftment, apoptosis, angiogenesis, scar formation, and cardiac functional recovery. Results. In vitro, cell apoptosis decreased 43%, and vascular endothelial growth factor (VEGF, insulin-like growth factor-1 (IGF-1, and plate-derived growth factor (PDGF increased 1.5-, 0.7-, and 1.2-fold, respectively, in hBcl-xL-MSCs versus wild type and vector-MSCs. In vivo, cell apoptosis decreased 40% and 26% in hBcl-xL-MSC group versus medium and vector-MSC group, respectively. Similar results were observed in cell engraftment, angiogenesis, scar formation, and cardiac functional recovery. Conclusions. Genetic modification of MSCs with hBcl-xL gene could be an intriguing strategy to improve the therapeutic efficacy of cell therapy in the treatment of heart infarction.

  19. Long-Term Engraftment and Fetal Globin Induction uponBCL11AGene Editing in Bone-Marrow-Derived CD34+Hematopoietic Stem and Progenitor Cells.

    Science.gov (United States)

    Chang, Kai-Hsin; Smith, Sarah E; Sullivan, Timothy; Chen, Kai; Zhou, Qianhe; West, Jason A; Liu, Mei; Liu, Yingchun; Vieira, Benjamin F; Sun, Chao; Hong, Vu P; Zhang, Mingxuan; Yang, Xiao; Reik, Andreas; Urnov, Fyodor D; Rebar, Edward J; Holmes, Michael C; Danos, Olivier; Jiang, Haiyan; Tan, Siyuan

    2017-03-17

    To develop an effective and sustainable cell therapy for sickle cell disease (SCD), we investigated the feasibility of targeted disruption of the BCL11A gene, either within exon 2 or at the GATAA motif in the intronic erythroid-specific enhancer, using zinc finger nucleases in human bone marrow (BM) CD34 + hematopoietic stem and progenitor cells (HSPCs). Both targeting strategies upregulated fetal globin expression in erythroid cells to levels predicted to inhibit hemoglobin S polymerization. However, complete inactivation of BCL11A resulting from bi-allelic frameshift mutations in BCL11A exon 2 adversely affected erythroid enucleation. In contrast, bi-allelic disruption of the GATAA motif in the erythroid enhancer of BCL11A did not negatively impact enucleation. Furthermore, BCL11A exon 2-edited BM-CD34 + cells demonstrated a significantly reduced engraftment potential in immunodeficient mice. Such an adverse effect on HSPC function was not observed upon BCL11A erythroid-enhancer GATAA motif editing, because enhancer-edited CD34 + cells achieved robust long-term engraftment and gave rise to erythroid cells with elevated levels of fetal globin expression when chimeric BM was cultured ex vivo. Altogether, our results support further clinical development of the BCL11A erythroid-specific enhancer editing in BM-CD34 + HSPCs as an autologous stem cell therapy in SCD patients.

  20. Long-Term Engraftment and Fetal Globin Induction upon BCL11A Gene Editing in Bone-Marrow-Derived CD34+ Hematopoietic Stem and Progenitor Cells

    Directory of Open Access Journals (Sweden)

    Kai-Hsin Chang

    2017-03-01

    Full Text Available To develop an effective and sustainable cell therapy for sickle cell disease (SCD, we investigated the feasibility of targeted disruption of the BCL11A gene, either within exon 2 or at the GATAA motif in the intronic erythroid-specific enhancer, using zinc finger nucleases in human bone marrow (BM CD34+ hematopoietic stem and progenitor cells (HSPCs. Both targeting strategies upregulated fetal globin expression in erythroid cells to levels predicted to inhibit hemoglobin S polymerization. However, complete inactivation of BCL11A resulting from bi-allelic frameshift mutations in BCL11A exon 2 adversely affected erythroid enucleation. In contrast, bi-allelic disruption of the GATAA motif in the erythroid enhancer of BCL11A did not negatively impact enucleation. Furthermore, BCL11A exon 2-edited BM-CD34+ cells demonstrated a significantly reduced engraftment potential in immunodeficient mice. Such an adverse effect on HSPC function was not observed upon BCL11A erythroid-enhancer GATAA motif editing, because enhancer-edited CD34+ cells achieved robust long-term engraftment and gave rise to erythroid cells with elevated levels of fetal globin expression when chimeric BM was cultured ex vivo. Altogether, our results support further clinical development of the BCL11A erythroid-specific enhancer editing in BM-CD34+ HSPCs as an autologous stem cell therapy in SCD patients.

  1. Effect of Bcl-xL overexpression on sialylation of Fc-fusion protein in recombinant Chinese hamster ovary cell cultures.

    Science.gov (United States)

    Lee, Jong Hyun; Kim, Yeon-Gu; Lee, Gyun Min

    2015-01-01

    The sialic acid of glycoproteins secreted by recombinant Chinese hamster ovary (rCHO) cells can be impaired by sialidase under culture conditions which promote the extracellular accumulation of this enzyme. To investigate the effect of Bcl-xL overexpression on the sialylation of glycoproteins produced in rCHO cell culture, two rCHO cell lines producing the same Fc-fusion protein, which were derived from DUKX-B11 and DG44, respectively, were engineered to have regulated Bcl-xL overexpression using the Tet-off system. For both cell lines, Bcl-xL overexpression improved cell viability and extended culture longevity in batch cultures. As a result, a maximum Fc-fusion protein titer increased by Bcl-xL overexpression though the extent of titer enhancement differed between the two cell lines. With Bcl-xL overexpression, the sialylation of Fc-fusion protein, which was assessed by isoelectric focusing gel and sialic acid content analyses, decreased more slowly toward the end of batch cultures. This was because Bcl-xL overexpression delayed the extracellular accumulation of sialidase activity by reducing cell lysis during batch cultures. Taken together, Bcl-xL overexpression in rCHO cell culture increased Fc-fusion protein production and also reduced the impairment of sialylation of Fc-fusion protein by maintaining high viability during batch cultures. © 2015 American Institute of Chemical Engineers.

  2. Boron neutron capture therapy induces apoptosis of glioma cells through Bcl-2/Bax

    Directory of Open Access Journals (Sweden)

    Mao Xinggang

    2010-12-01

    Full Text Available Abstract Background Boron neutron capture therapy (BNCT is an alternative treatment modality for patients with glioma. The aim of this study was to determine whether induction of apoptosis contributes to the main therapeutic efficacy of BNCT and to compare the relative biological effect (RBE of BNCT, γ-ray and reactor neutron irradiation. Methods The neutron beam was obtained from the Xi'an Pulsed Reactor (XAPR and γ-rays were obtained from [60Co] γ source of the Fourth Military Medical University (FMMU in China. Human glioma cells (the U87, U251, and SHG44 cell lines were irradiated by neutron beams at the XAPR or [60Co] γ-rays at the FMMU with different protocols: Group A included control nonirradiated cells; Group B included cells treated with 4 Gy of [60Co] γ-rays; Group C included cells treated with 8 Gy of [60Co] γ-rays; Group D included cells treated with 4 Gy BPA (p-borono-phenylalanine-BNCT; Group E included cells treated with 8 Gy BPA-BNCT; Group F included cells irradiated in the reactor for the same treatment period as used for Group D; Group G included cells irradiated in the reactor for the same treatment period as used for Group E; Group H included cells irradiated with 4 Gy in the reactor; and Group I included cells irradiated with 8 Gy in the reactor. Cell survival was determined using the 3-(4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium (MTT cytotoxicity assay. The morphology of cells was detected by Hoechst33342 staining and transmission electron microscope (TEM. The apoptosis rate was detected by flow cytometer (FCM. The level of Bcl-2 and Bax protein was measured by western blot analysis. Results Proliferation of U87, U251, and SHG44 cells was much more strongly inhibited by BPA-BNCT than by irradiation with [60Co] γ-rays (P 60Co] γ-rays (P P Conclusions Compared with ��-ray and reactor neutron irradiation, a higher RBE can be achieved upon treatment of glioma cells with BNCT. Glioma cell apoptosis induced by

  3. Clinical profiling of BCL-2 family members in the setting of BRAF inhibition offers a rationale for targeting de novo resistance using BH3 mimetics.

    Directory of Open Access Journals (Sweden)

    Dennie T Frederick

    Full Text Available While response rates to BRAF inhibitiors (BRAFi are high, disease progression emerges quickly. One strategy to delay the onset of resistance is to target anti-apoptotic proteins such as BCL-2, known to be associated with a poor prognosis. We analyzed BCL-2 family member expression levels of 34 samples from 17 patients collected before and 10 to 14 days after treatment initiation with either vemurafenib or dabrafenib/trametinib combination. The observed changes in mRNA and protein levels with BRAFi treatment led us to hypothesize that combining BRAFi with a BCL-2 inhibitor (the BH3-mimetic navitoclax would improve outcome. We tested this hypothesis in cell lines and in mice. Pretreatment mRNA levels of BCL-2 negatively correlated with maximal tumor regression. Early increases in mRNA levels were seen in BIM, BCL-XL, BID and BCL2-W, as were decreases in MCL-1 and BCL2A. No significant changes were observed with BCL-2. Using reverse phase protein array (RPPA, significant increases in protein levels were found in BIM and BID. No changes in mRNA or protein correlated with response. Concurrent BRAF (PLX4720 and BCL2 (navitoclax inhibition synergistically reduced viability in BRAF mutant cell lines and correlated with down-modulation of MCL-1 and BIM induction after PLX4720 treatment. In xenograft models, navitoclax enhanced the efficacy of PLX4720. The combination of a selective BRAF inhibitor with a BH3-mimetic promises to be an important therapeutic strategy capable of enhancing the clinical efficacy of BRAF inhibition in many patients that might otherwise succumb quickly to de novo resistance. Trial registrations: ClinicalTrials.gov NCT01006980; ClinicalTrials.gov NCT01107418; ClinicalTrials.gov NCT01264380; ClinicalTrials.gov NCT01248936; ClinicalTrials.gov NCT00949702; ClinicalTrials.gov NCT01072175.

  4. BCL2 gene aberration as an IPI-independent marker for poor outcome in non-germinal-centre diffuse large B cell lymphoma.

    Science.gov (United States)

    Obermann, E C; Csato, M; Dirnhofer, S; Tzankov, A

    2009-10-01

    Diffuse large B cell lymphoma (DLBCL) is the most common lymphoid malignancy in the western hemisphere, and is characterised by a highly variable outcome that impedes individual risk assessment. Lacking reliable biomarkers, the international prognostic index (IPI) has been the most reliable factor to predict survival and stratify patients for therapy. The aim of this study was to investigate the frequency and potential prognostic role of BCL2 aberrations on the chromosomal level and the protein level in a large DLBCL collective. Fluorescence in situ hybridisation (FISH) with commercially available dual-colour break-apart probes and immunohistochemistry were used to assess BCL2 gene abnormalities and bcl2 protein expression on validated tissue microarrays containing 224 well-characterised cases of primary DLBCL. FISH analysis of BCL2 revealed a break in 40/215 cases (19%) and a gain in 66/171 (39%) cases. Only BCL2 gains correlated with bcl2 protein expression (p = 0.001). Presence of any BCL2 gene abnormality, particularly gains, correlated independently of the IPI with a significantly worse prognosis in DLBCL of non-germinal centre (non-GC) phenotype as opposed to DLBCL of non-GC type without this genetic alteration (p = 0.003). DLBCL of germinal centre phenotype did not show this association. Cases of DLBCL of the non-GC type with BCL2 gene aberration are accompanied by a significantly worse prognosis as opposed to cases without such gene abnormalities. It may be helpful to asses BCL2 gene abnormalities by FISH in addition to assessing established parameters for individual risk estimation in DLBCL.

  5. Safflor yellow B suppresses angiotensin II-mediated human umbilical vein cell injury via regulation of Bcl-2/p22{sup phox} expression

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Chaoyun; He, Yanhao [School of Pharmaceutical Sciences, Binzhou Medical University, Yantai, Shandong 264003 (China); Department of Pharmacology, Xi' an Jiaotong University School of Medicine, Key Laboratory of Environment and Genes Related to Disease, Ministry of Education, Xi' an, Shaanxi 710061 (China); Yang, Ming; Sun, Hongliu; Zhang, Shuping [School of Pharmaceutical Sciences, Binzhou Medical University, Yantai, Shandong 264003 (China); Wang, Chunhua, E-mail: chunhuawang2012@163.com [School of Pharmaceutical Sciences, Binzhou Medical University, Yantai, Shandong 264003 (China)

    2013-11-15

    Intracellular reactive oxygen species (ROS) are derived from nicotinamide adenine dinucleotide phosphate (NADPH) oxidase. Angiotensin II (Ang II) can cause endothelial dysfunction by promoting intracellular ROS generation. Safflor yellow B (SYB) effectively inhibits ROS generation by upregulating Bcl-2 expression. In this study, we examined the effects of SYB on Ang II-induced injury to human umbilical vein endothelial cells (HUVECs), and elucidated the roles of NADPH oxidase and Bcl-2. We treated cultured HUVECs with Ang II, SYB, and Bcl-2 siRNA, and determined NADPH oxidase activity and ROS levels. Furthermore, cellular and mitochondrial physiological states were evaluated, and the expression levels of target proteins were analyzed. Ang II significantly enhanced intracellular ROS levels, caused mitochondrial membrane dysfunction, and decreased cell viability, leading to apoptosis. This was associated with increased expression of AT1R and p22{sup phox}, increased NADPH oxidase activity, and an increased ratio of Bax/Bcl-2, leading to decreases in antioxidant enzyme activities, which were further strengthened after blocking Bcl-2. Compared to Ang II treatment alone, co-treatment with SYB significantly reversed HUVEC injury. Taken together, these results demonstrate that SYB could significantly protect endothelial cells from Ang II-induced cell damage, and that it does so by upregulating Bcl-2 expression and inhibiting ROS generation. - Highlights: • Angiotensin II depresses mitochondria physiological function. • Angiotensin II activates NADPH oxidase via up-regulating expresion of p22{sup phox}. • Bcl-2 plays a pivotal role in improving mitochondria function and regulates ROS level. • Inhibitor of Bcl-2 promotes angiotensin II mediated HUVEC injury. • SYB attenuates angiotensin II mediated HUVEC injury via up regulating Bcl-2 expression.

  6. Activation of Akt/GSK3β and Akt/Bcl-2 signaling pathways in nickel-transformed BEAS-2B cells.

    Science.gov (United States)

    Pan, Jing-Ju; Chang, Qing-Shan; Wang, Xin; Son, Young-Ok; Liu, Jiankang; Zhang, Zhuo; Bi, Yong-Yi; Shi, Xianglin

    2011-11-01

    The Akt signaling pathway has been implicated in a wide range of cellular functions involving cell survival and proliferation, angiogenesis, metabolism and cell migration. Accumulating evidence suggests that Akt perturbations play an important role in human malignancy. Here, we investigated Akt perturbation in nickel-transformed cells. Chronic treatment of human bronchial epithelial BEAS-2B cells with low doses of nickel chloride resulted in cell transformation demonstrated by anchorage-independent (AI) growth, increased cell growth and alterations of cell growth pattern. Western blot assays show that phosphorylation of Akt at Ser473, but not that of p38, JNK and ERK, was increased in nickel-transformed cells compared with controls. Inhibition of Akt or PI3K by pharmacological or biochemical interference suppressed nickel AI growth and cell growth of transformed cells. Activation of Akt led to inhibition of GSK3β by phosphorylation at Ser9 in nickel-transformed cells. In addition, two major anti-apoptotic proteins of the Bcl family, Bcl-2 and Bcl-XL, were increased in nickel-transformed cells. By employing the small interfering RNA technique (siRNA), our results showed that siRNA Akt attenuated the expression of Bcl-2 and Bcl-XL in nickel-transformed cells, indicating that induction of Bcl-2 and Bcl-XL was likely mediated through Akt. ROS generation was decreased in nickel-transformed cells compared with controls. Moreover, down-regulation of retinoblastoma protein (Rb) was observed in nickel-transformed cells. Taken together, these findings demonstrate that activation of Akt, followed by GSK3β inhibition and Bcl-2, Bcl-XL up-regulation and decrease of ROS generation, along with a synergistic effect of Rb down-regulation may cause apoptosis resistance, contributing to the overall mechanism of nickel carcinogenesis.

  7. Safflor yellow B suppresses angiotensin II-mediated human umbilical vein cell injury via regulation of Bcl-2/p22phox expression

    International Nuclear Information System (INIS)

    Wang, Chaoyun; He, Yanhao; Yang, Ming; Sun, Hongliu; Zhang, Shuping; Wang, Chunhua

    2013-01-01

    Intracellular reactive oxygen species (ROS) are derived from nicotinamide adenine dinucleotide phosphate (NADPH) oxidase. Angiotensin II (Ang II) can cause endothelial dysfunction by promoting intracellular ROS generation. Safflor yellow B (SYB) effectively inhibits ROS generation by upregulating Bcl-2 expression. In this study, we examined the effects of SYB on Ang II-induced injury to human umbilical vein endothelial cells (HUVECs), and elucidated the roles of NADPH oxidase and Bcl-2. We treated cultured HUVECs with Ang II, SYB, and Bcl-2 siRNA, and determined NADPH oxidase activity and ROS levels. Furthermore, cellular and mitochondrial physiological states were evaluated, and the expression levels of target proteins were analyzed. Ang II significantly enhanced intracellular ROS levels, caused mitochondrial membrane dysfunction, and decreased cell viability, leading to apoptosis. This was associated with increased expression of AT1R and p22 phox , increased NADPH oxidase activity, and an increased ratio of Bax/Bcl-2, leading to decreases in antioxidant enzyme activities, which were further strengthened after blocking Bcl-2. Compared to Ang II treatment alone, co-treatment with SYB significantly reversed HUVEC injury. Taken together, these results demonstrate that SYB could significantly protect endothelial cells from Ang II-induced cell damage, and that it does so by upregulating Bcl-2 expression and inhibiting ROS generation. - Highlights: • Angiotensin II depresses mitochondria physiological function. • Angiotensin II activates NADPH oxidase via up-regulating expresion of p22 phox . • Bcl-2 plays a pivotal role in improving mitochondria function and regulates ROS level. • Inhibitor of Bcl-2 promotes angiotensin II mediated HUVEC injury. • SYB attenuates angiotensin II mediated HUVEC injury via up regulating Bcl-2 expression

  8. Combination of Bcl-2 and MYC protein expression improves high-risk stratification in diffuse large B-cell lymphoma

    Directory of Open Access Journals (Sweden)

    Wang J

    2015-09-01

    Full Text Available Jing Wang,* Min Zhou,* Jing-Yan Xu,* Bing Chen, Jian OuyangDepartment of Hematology, The Affiliated Drum Tower Hospital of Nanjing University Medical School, Nanjing, Jiangsu, People’s Republic of China*These authors contributed equally to this work and should be considered as cofirst authorsPurpose: To evaluate whether the addition of two biological markers (MYC and BCL-2 protein overexpression improves the stratification of high-risk patients with diffuse large B-cell lymphoma (DLBCL.Method: Seven risk factors were identified at diagnosis, and a maximum of 7 points were assigned to each patient. The patients were classified according to four risk groups: low (0–1, low-intermediate (2–3, high-intermediate (4, and high (5–7. Only high-risk patients with DLBCL were included in this analysis. We retrospectively examined 20 cases from 2008 to 2013 at the Nanjing Drum Tower Hospital.Results: The median expression of MYC protein was 60%, and 17 of 20 (65% evaluable cases overexpressed MYC. The median expression of BCL-2 protein was also 60%. Eighteen of 20 (90% evaluable cases showed BCL-2 overexpression. Additionally, 12 out of 20 cases (60% demonstrated coexpression of MYC and BCL-2 proteins. The percentages of overall survival and progression-free survival at the median follow-up time (36 months were 33.3%±16.1% and 16.9%±13.5%, respectively. By comparison, nine, four, and 20 patients were classified as high risk based on the International Prognostic Index (IPI, National Comprehensive Cancer Network(NCCN-IPI, and revised IPI criteria, respectively. According to the IPI and NCCN-IPI stratification, the risk groups demonstrated closely overlapping survival curves. In addition, four out of 20 cases were identified as low-intermediate risk according to the NCCN-IPI criteria.Conclusion: The addition of MYC and BCL-2 protein expression to the IPI could identify a subset of DLBCL patients with high-risk clinicopathological characteristics and

  9. PENGARUH EKSTRAK ETHANOL PROPOLIS TERHADAP EKSPRESI PROTEIN Bcl2, CYCLIN D1 DAN INDUKSI APOPTOSIS PADA KULTUR SEL KANKER KOLON

    Directory of Open Access Journals (Sweden)

    Haryono Yuniarto

    2017-06-01

    Full Text Available Kanker kolorektal menempati urutan kejadian kanker ketiga di seluruh dunia, dengan lebih dari 1 juta angka kejadian tiap tahunnya. Berbagai strategi terapi pengobatan kanker kolorektal tetapi relatif belum optimal. Oleh karena itu, terdapat kebutuhan mengembangkan terapi alternatif sebagai pendamping. Propolis menunjukkan aktivitas proapoptosis pada berbagai jenis sel kanker. Mengetahui pengaruh pemberian propolis yang berasal dari Kerjo, Karanganyar, Indonesia terhadap induksi proses apoptosis dan aktivitas antiproliferasi, terutama terkait dengan penekanan ekspresi protein Bcl 2 dan cyclin D1 pada kultur sel WiDr (cell line kanker kolon. Penelitian eksperimental laboratorik menggunakan post test with control group design. Penelitian dilakukan pada kultur sel WiDr (sel kanker kolon dengan pemberian propolis. Pengamatan ekspresi protein Cyclin D1 dan Bcl2 dilakukan dengan metode imunositokimia, sedangkan pengamatan induksi apoptosis dilakukan dengan flowcytometry. Analisis statistik dengan uji Kruskal-Wallis, signifikan bila p <0,05. Rata-rata ekspresi Bcl2 pada kelima kelompok yaitu kontrol 83.40 ± 0.69 μg/ml, EEP 1/2 IC50 60.63 ± 0.40, EEP IC50 33.77 ± 1.08 μg/ml, EEP 2 IC50 24.28 ± 1.91 μg/ml, 5fluorouracil 12.74 ± 2.19 μg/ml. Terdapat perbedaan bermakna ekspresi Bcl2 antara kelompok uji dibandingkan kelompok kontrol (p < 0,001. Rata-rata ekspresi cyclin D1 pada kelima kelompok yaitu kontrol 83.77 ± 0.39 μg/ml, EEP 1/2 IC50 61.44 ± 0.41, EEP IC50 36.67 ± 1.18 μg/ml, EEP 2 IC50 24.50 ± 0.38 μg/ml, 5fluorouracil 13.42 ± 1.04μg/ml. Terdapat perbedaan bermakna ekspresi cyclin D1 antara kelompok uji dibandingkan kelompok kontrol (p < 0,001. Pemberian ekstrak etanol propolis mempunyai pengaruh menekan ekspresi Bcl2, cyclin D1, dan menginduksi apoptosis pada kultur sel kanker kolon (WiDr Cell Line.   Kata Kunci: Ekstrak Ethanol Propolis, Bcl2, cyclin D1, Sel WiDr

  10. Correlation and role of nitric oxide (NO) and BCL-2 in duchenne muscular dystrophy (DMD) patients

    International Nuclear Information System (INIS)

    Moawed, F.S.M.

    2009-01-01

    Duchenne muscular dystrophy (DMD) is a lethal, degenerative muscle disease caused by a genetic mutation that leads to the complete absence of the cytoskeletal protein dystrophin in muscle fibers. Although the mechanisms underlying muscle degeneration are still uncertain, oxidative-damage and regenerating aging have been proposed to play a key role. The aim of the present study was to test for these two theories, and to evaluate the possible ameliorative effect of He;Ne laser on them. Subjects and Methods: twenty-two duchenne muscular dystrophy boys (7-15 years old ) with proven dystrophin gene mutation, together with twenty-two normal males, who served as controls, were enrolled for this study. Initial blood samples were taken for the determinations of creatine kinase (CK), markers of replicative aging; in terms of plasma and lymphocyte Bcl-2 protein and apoptosis percentage in circulating mononuclear cells, along with those of oxidative stress in terms of lipid peroxidation (as plasma malondialdehyde MDA), catalase activity, cholesterol, triacylglycerol and nitric oxide. Whole blood samples were then irradiated with 2.5 j/cm 2 by He-Ne laser at wave length 632.8 nm and power output 10 MW.

  11. Impact of conditional deletion of the pro-apoptotic BCL-2 family member BIM in mice.

    Science.gov (United States)

    Herold, M J; Stuchbery, R; Mérino, D; Willson, T; Strasser, A; Hildeman, D; Bouillet, P

    2014-10-09

    The pro-apoptotic BH3-only BCL-2 family member BIM is a critical determinant of hematopoietic cell development and homeostasis. It has been argued that the striking hematopoietic abnormalities of BIM-deficient mice (accumulation of lymphocytes and granulocytes) may be the result of the loss of the protein throughout the whole animal rather than a consequence intrinsic to the loss of BIM in hematopoietic cells. To address this issue and allow the deletion of BIM in specific cell types in future studies, we have developed a mouse strain with a conditional Bim allele as well as a new Cre transgenic strain, Vav-CreER, in which the tamoxifen-inducible CreER recombinase (fusion protein) is predominantly expressed in the hematopoietic system. We show that acute loss of BIM in the adult mouse rapidly results in the hematopoietic phenotypes previously observed in mice lacking BIM in all tissues. This includes changes in thymocyte subpopulations, increased white blood cell counts and resistance of lymphocytes to BIM-dependent apoptotic stimuli, such as cytokine deprivation. We have validated this novel conditional Bim knockout mouse model using established and newly developed CreER strains (Rosa26-CreER and Vav-CreER) and will make these exciting new tools for studies on cell death and cancer available.

  12. Structural Mechanism for Regulation of Bcl-2 protein Noxa by phosphorylation

    Science.gov (United States)

    Karim, Christine B.; Michel Espinoza-Fonseca, L.; James, Zachary M.; Hanse, Eric A.; Gaynes, Jeffrey S.; Thomas, David D.; Kelekar, Ameeta

    2015-09-01

    We showed previously that phosphorylation of Noxa, a 54-residue Bcl-2 protein, at serine 13 (Ser13) inhibited its ability to promote apoptosis through interactions with canonical binding partner, Mcl-1. Using EPR spectroscopy, molecular dynamics (MD) simulations and binding assays, we offer evidence that a structural alteration caused by phosphorylation partially masks Noxa’s BH3 domain, inhibiting the Noxa-Mcl-1 interaction. EPR of unphosphorylated Noxa, with spin-labeled amino acid TOAC incorporated within the BH3 domain, revealed equilibrium between ordered and dynamically disordered states. Mcl-1 further restricted the ordered component for non-phosphorylated Noxa, but left the pSer13 Noxa profile unchanged. Microsecond MD simulations indicated that the BH3 domain of unphosphorylated Noxa is housed within a flexible loop connecting two antiparallel β-sheets, flanked by disordered N- and C-termini and Ser13 phosphorylation creates a network of salt-bridges that facilitate the interaction between the N-terminus and the BH3 domain. EPR showed that a spin label inserted near the N-terminus was weakly immobilized in unphosphorylated Noxa, consistent with a solvent-exposed helix/loop, but strongly constrained in pSer13 Noxa, indicating a more ordered peptide backbone, as predicted by MD simulations. Together these studies reveal a novel mechanism by which phosphorylation of a distal serine inhibits a pro-apoptotic BH3 domain and promotes cell survival.

  13. An Oncogenic Role for Alternative NF-κB Signaling in DLBCL Revealed upon Deregulated BCL6 Expression

    Directory of Open Access Journals (Sweden)

    Baochun Zhang

    2015-05-01

    Full Text Available Diffuse large B cell lymphoma (DLBCL is a complex disease comprising diverse subtypes and genetic profiles. Possibly because of the prevalence of genetic alterations activating canonical NF-κB activity, a role for oncogenic lesions that activate the alternative NF-κB pathway in DLBCL has remained elusive. Here, we show that deletion/mutation of TRAF3, a negative regulator of the alternative NF-κB pathway, occurs in ∼15% of DLBCLs and that it often coexists with BCL6 translocation, which prevents terminal B cell differentiation. Accordingly, in a mouse model constitutive activation of the alternative NF-κB pathway cooperates with BCL6 deregulation in DLBCL development. This work demonstrates a key oncogenic role for the alternative NF-κB pathway in DLBCL development.

  14. BCL6 interacting corepressor contributes to germinal center T follicular helper cell formation and B cell helper function

    Science.gov (United States)

    Yang, Jessica A.; Tubo, Noah J.; Gearhart, Micah D.; Bardwell, Vivian J.; Jenkins, Marc K.

    2015-01-01

    CD4+ germinal center (GC) T follicular helper (GC-Tfh) cells help B cells become long-lived plasma cells and memory cells. The transcriptional repressor BCL6 plays a key role in GC-Tfh formation by inhibiting the expression of genes that promote differentiation into other lineages. We determined whether BCOR, a component of a Polycomb repressive complex that interacts with the BCL6 BTB domain, influences GC-Tfh differentiation. T cell-targeted BCOR deficiency led to a substantial loss of peptide:MHCII-specific GC-Tfh cells following Listeria monocytogenes infection and a 2-fold decrease following immunization with a peptide in CFA. The reduction in GC-Tfh cells was associated with diminished plasma cell and GC B cell formation. Thus, T cell-expressed BCOR is critical for optimal GC-Tfh differentiation and humoral immunity. PMID:25964495

  15. Cutting edge: Bcl6-interacting corepressor contributes to germinal center T follicular helper cell formation and B cell helper function.

    Science.gov (United States)

    Yang, Jessica A; Tubo, Noah J; Gearhart, Micah D; Bardwell, Vivian J; Jenkins, Marc K

    2015-06-15

    CD4(+) germinal center (GC)-T follicular helper (Tfh) cells help B cells become long-lived plasma cells and memory cells. The transcriptional repressor Bcl6 plays a key role in GC-Tfh formation by inhibiting the expression of genes that promote differentiation into other lineages. We determined whether BCOR, a component of a Polycomb repressive complex that interacts with the Bcl6 BTB domain, influences GC-Tfh differentiation. T cell-targeted BCOR deficiency led to a substantial loss of peptide:MHC class II-specific GC-Tfh cells following Listeria monocytogenes infection and a 2-fold decrease following immunization with a peptide in CFA. The reduction in GC-Tfh cells was associated with diminished plasma cell and GC B cell formation. Thus, T cell-expressed BCOR is critical for optimal GC-Tfh cell differentiation and humoral immunity. Copyright © 2015 by The American Association of Immunologists, Inc.

  16. [Effects of blueberry on apoptosis and expression of Bcl-2 and Bax in HSC-T6].

    Science.gov (United States)

    Lu, Shuang; Cheng, Mingliang; Yang, Demeng; Liu, Yang; Guan, Li; Wu, Jun

    2015-08-18

    To investigate the effects of blueberry on the apoptosis, expression of Bcl-2 and Bax in rat hepatic stellate cell (HSC-T6). 10% blueberry serum at low, middle and high dose, 10% Fu-Fang-Bie-Jia-Ruan-Gan tablet serum and 10% saline serum were prepared by method of serum pharmacology. Subcultured HSC-T6 was divided into saline serum control group, blueberry serum at low, middle, high dose and Fu-Fang-Bie-Jia-Ruan-Gan tablet serum group, and then was respectively incubated at different dose of 10% blueberry serum, 10% Fu-Fang-Bie-Jia-Ruan-Gan tablet serum and 10% saline serum for 72 hours.Apoptosis of HSC-T6 was detected using flow cytometry with annexin V FITC/PI double staining. The expression of Bcl-2 and Bax in HSC-T6 were examined using immunocytochemistry and Western blotting, respectively. There was no significant difference for HSC-T6 Bax protein expression in the low, middle and high dose blueberry serum groups, compared with saline serum control group, respectively.In the high-dose blueberry serum group HSC-T6 early and total apoptosis rate increased significantly compared with the saline serum control group (5.55% ± 0.98% vs 2.53% ± 0.46%, 7.01% ± 1.05% vs 2.96% ± 0.81%, both Pblueberry serum group showed no significant difference with the saline serum control group. Blueberry can induce HSC-T6 apoptosis by down-regulating Bcl-2 expression and decreasing the ratio of Bcl-2/Bax in HSC-T6 cells, so it may have potential interference effects on hepatic fibrosis.

  17. BAX and BCL-2 polymorphisms, as predictors of proliferative vitreoretinopathy development in patients suffering retinal detachment: the Retina 4 project.

    Science.gov (United States)

    Pastor-Idoate, Salvador; Rodríguez-Hernández, Irene; Rojas, Jimena; Fernández, Itziar; García-Gutierrez, María-Teresa; Ruiz-Moreno, Jose M; Rocha-Sousa, Amandio; Ramkissoon, Yashin D; Harsum, Steven; MacLaren, Robert E; Charteris, David G; Van Meurs, Jan C; González-Sarmiento, Rogelio; Pastor, Jose C

    2015-11-01

    To compare the distribution of BCL-2 -938C>A (rs2279115) and BAX -248G>A (rs4645878) genotypes among European subjects undergoing rhegmatogenous retinal detachment (RRD) surgery in relation to the further development of proliferative vitreoretinopathy (PVR). A case-control gene association study, as a part of Retina 4 project, was designed. rs2279115 and rs4645878 polymorphisms were analysed in 555 samples from patients with RRD (134 with PVR secondary to surgery). Proportions of genotypes and AA homozygous groups of BCL-2 and BAX polymorphisms between subsamples were analysed in two phases. Genotypic and allelic frequencies were compared in global sample and in subsamples. BAX: Differences were observed in the genotype frequencies and in AA carriers between controls and cases in the global series. The odds ratio (OR) of A carriers in the global sample was 1.7 (95% CI: 1.23-2.51). Proportions of genotypes in Spain + Portugal were significant different. The OR of A carriers from Spain and Portugal was 1.8 (95% CI: 1.11-2.95). BCL-2: No significant differences were observed in genotype frequencies. However, proportions of genotypes in Spain + Portugal were significant. A protective effect (OR: 0.6 95% CI: 0.43-0.96) was found in A carriers from Spain and Portugal. Results suggest that A allele of rs4645878 could be a biomarker of high risk of developing PVR in patients undergoing RD surgery. The possible role of BCL-2 (inhibitor of necroptosis pathway) as a possible new target in PVR prophylaxis should be investigated. © 2015 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

  18. Immunohistochemical expression of Bcl-2 and Ki-67 in oral lichen planus and leukoplakia with different degrees of dysplasia.

    Science.gov (United States)

    Pigatti, Fernanda Mombrini; Taveira, Luís Antônio de Assis; Soares, Cléverson Teixeira

    2015-02-01

    Oral lichen planus (OLP) is a chronic inflammatory disease of unknown cause. Malignant transformation in OLP lesions may be favored by changes in the expression of proteins that regulate cell proliferation and apoptosis. This study aimed to investigate these issues by immunohistochemical staining for Bcl-2 and Ki-67 and by correlating histopathological findings in samples from lesions of OLP and leukoplakia with epithelial dysplasia. Data for patients with OLP or leukoplakia with moderate or severe epithelial dysplasia recorded during 2006-2011 were retrospectively reviewed. The study samples represented 37 subjects with OLP (n = 14), leukoplakia with moderate (n = 8) or severe (n = 6) epithelial dysplasia, and normal buccal mucosa (controls, n = 9). New sections were subjected to histological examination and immunohistochemistry for Bcl-2 and Ki-67 in the basal layer, suprabasal layer, and inflammatory infiltrate, respectively. All basal layer sections stained either negative or positive in leukoplakia, 85.7% of sections indicated positivity in leukoplakia (64.3%) sections stained positive for Ki-67 in >50% of cells. All suprabasal sections stained either negative or positive in leukoplakia (42.9% and 57.1%, respectively), and control (88.9% and 11.1%, respectively) samples. Suprabasal staining for Ki-67 was negative or positive in leukoplakia (7.1% and 92.9%, respectively), and controls (88.9% and 11.1%, respectively). Staining for Bcl-2 in inflammatory infiltrate in OLP was positive in 92.9% of sections. Expression of Bcl-2 may play a dual role in tumor development and progression. Increased cell proliferation in the epithelium may present a predisposition to cancer in OLP. The expression of Ki-67 can be considered as an adjunct marker for proliferative activity in lesions with malignant potential. The prognostic value of these immunomarkers in the evaluation of precancerous oral lesions requires further investigation. © 2014 The International Society

  19. Clinical significance of T-bet, GATA-3, and Bcl-6 transcription factor expression in bladder carcinoma.

    Science.gov (United States)

    Bahria-Sediki, Islem Ben; Yousfi, Nadhir; Paul, Catherine; Chebil, Mohamed; Cherif, Mohamed; Zermani, Rachida; El Gaaied, Amel Ben Ammar; Bettaieb, Ali

    2016-05-30

    The aim of this study was to investigate the clinical significance of three immune cell-related transcription factors, T-bet, GATA-3 and Bcl-6 in bladder cancer in Tunisian patients. Expression of T-bet, GATA-3 and Bcl-6 genes was assessed using RT-qPCR in 65 bladder cancers from patients: 32 being diagnosed as low- and medium-grade, 31 as high-grade, 25 as muscle invasive stage and 39 as non-muscle invasive stage. Gene expression was statistically correlated according to the grade, the stage, tobacco consumption, the BCG response and disease severity. T-bet levels in patients with high-grade bladder cancer were significantly elevated compared to patients with low- or medium-grade bladder cancer (p = 0.005). In invasive carcinoma (T2-T4), the T-bet levels were significantly higher than in superficial non-invasive bladder tumors (Tis, Ta, and T1) (p = 0.02). However, T-bet is predictive of the response to BCG. Its expression is high in good responders to BCG (p = 0.02). In contrast, the expression of GATA-3 and Bcl-6 in non-invasive carcinoma (p = 0.008 and p = 0.0003) and in patients with low- and medium-grade cancers (p = 0.001 and p T-bet expression. Our results suggest that T-bet expression in bladder tumors could be a positive prognostic indicator of BCG therapy, even if high levels are found in high-grade and stage of the disease. However, GATA-3 and Bcl-6 expression could be considered as predictive factors for good patient survival.

  20. Paclitaxel sensitivity of breast cancer cells requires efficient mitotic arrest and disruption of Bcl-xL/Bak interaction.

    Science.gov (United States)

    Flores, M Luz; Castilla, Carolina; Ávila, Rainiero; Ruiz-Borrego, Manuel; Sáez, Carmen; Japón, Miguel A

    2012-06-01

    Taxanes are being used for the treatment of breast cancer. However, cancer cells frequently develop resistance to these drugs with the subsequent recurrence of the tumor. MDA-MB-231 and T-47D breast cancer cell lines were used to assess the effect of paclitaxel treatment on apoptosis and cell cycle, the possible mechanisms of paclitaxel resistance as well as the enhancement of paclitaxel-induced apoptosis based on its combination with phenylethyl isothiocyanate (PEITC). T-47D cells undergo apoptosis in response to paclitaxel treatment. The induction of apoptosis was associated with a robust mitotic arrest and the disruption of Bcl-xL/Bak interaction. By contrary, MDA-MB-231 cells were insensitive to paclitaxel-induced apoptosis and this was associated with a high percentage of cells that slip out of paclitaxel-imposed mitotic arrest and also with the maintenance of Bcl-xL/Bak interaction. The sequential treatment of MDA-MB-231 cells with PEITC followed by paclitaxel inhibited the slippage induced by paclitaxel and increased the apoptosis induction achieved with any of the drugs alone. In breast cancer tissues, high Bcl-xL expression was correlated with a shorter time of disease-free survival in patients treated with a chemotherapeutic regimen that contains paclitaxel, in a statistically significant way. Thus, resistance to paclitaxel in MDA-MB-231 cells is related to the inability to disrupt the Bcl-xL/Bak interaction and increased slippage. In this context, the combination of a drug that induces a strong mitotic arrest, such as paclitaxel, with another that inhibits slippage, such as PEITC, translates into increased apoptotic induction.

  1. Acute ethanol exposure-induced autophagy-mediated cardiac injury via activation of the ROS-JNK-Bcl-2 pathway.

    Science.gov (United States)

    Zhu, Zhongxin; Huang, Yewei; Lv, Lingchun; Tao, Youli; Shao, Minglong; Zhao, Congcong; Xue, Mei; Sun, Jia; Niu, Chao; Wang, Yang; Kim, Sunam; Cong, Weitao; Mao, Wei; Jin, Litai

    2018-02-01

    Binge drinking is associated with increased cardiac autophagy, and often triggers heart injury. Given the essential role of autophagy in various cardiac diseases, this study was designed to investigate the role of autophagy in ethanol-induced cardiac injury and the underlying mechanism. Our study showed that ethanol exposure enhanced the levels of LC3-II and LC3-II positive puncta and promoted cardiomyocyte apoptosis in vivo and in vitro. In addition, we found that ethanol induced autophagy and cardiac injury largely via the sequential triggering of reactive oxygen species (ROS) accumulation, activation of c-Jun NH2-terminal kinase (JNK), phosphorylation of Bcl-2, and dissociation of the Beclin 1/Bcl-2 complex. By contrast, inhibition of ethanol-induced autophagic flux with pharmacologic agents in the hearts of mice and cultured cells significantly alleviated ethanol-induced cardiomyocyte apoptosis and heart injury. Elimination of ROS with the antioxidant N-acetyl cysteine (NAC) or inhibition of JNK with the JNK inhibitor SP600125 reduced ethanol-induced autophagy and subsequent autophagy-mediated apoptosis. Moreover, metallothionein (MT), which can scavenge reactive oxygen and nitrogen species, also attenuated ethanol-induced autophagy and cell apoptosis in MT-TG mice. In conclusion, our findings suggest that acute ethanol exposure induced autophagy-mediated heart toxicity and injury mainly through the ROS-JNK-Bcl-2 signaling pathway. © 2017 Wiley Periodicals, Inc.

  2. Rasagiline delays retinal degeneration in a mouse model of retinitis pigmentosa via modulation of Bax/Bcl-2 expression.

    Science.gov (United States)

    Garcia-Delgado, Ana B; Valdés-Sánchez, Lourdes; Calado, Sofia M; Diaz-Corrales, Francisco J; Bhattacharya, Shom S

    2018-01-25

    Retinitis pigmentosa (RP) is an inherited disease characterized by a progressive degeneration of rod photoreceptors. An imbalance between pro- and antiapoptotic factors, such as Bax/Bcl-2, has been involved in retinal degeneration. To date, no cure or effective treatments are available for RP. Rasagiline is an antiparkinsonian drug that has shown neuroprotective effects in part attributed to a modulation of Bax/Bcl-2 expression. In this study, we have evaluated the use of rasagiline as a potential treatment for RP. Newborn rd10 mice, a RP model, were treated with oral rasagiline during 30 days followed by a functional and morphological characterization of their mouse retinas. Treated animals showed a significant improvement in visual acuity and in the electrical responses of photoreceptors to light stimuli. Rasagiline delayed photoreceptor degeneration, which was confirmed not only by a high photoreceptor nuclei counting, but also by a sustained expression of photoreceptor-specific markers. In addition, the expression of proapoptotic Bax decreased, whereas the antiapoptotic factor Bcl-2 increased after rasagiline treatment. This study provides new evidences regarding the neuroprotective effect of rasagiline in the retina, and it brings new insight into the development of future clinical trials using this well-established antiparkinsonian drug to treat RP. © 2018 John Wiley & Sons Ltd.

  3. Expression of the apoptosis-related genes Bcl-2 and p53 in clinical samples from endometrial carcinoma patients.

    Science.gov (United States)

    González-Rodilla, Irene; Verna, Virginia; Muñoz, Ana-Belén; Estévez, José; Boix, Mercedes; Schneider, José

    2011-12-01

    Although alterations in the mechanisms of apoptosis are an integral part of the tumor phenotype, their precise role in endometrial carcinoma is still obscure. The aim was to determine whether Bcl-2 plays a similar biological role in endometrial cancer as in breast cancer, endometrial cancer being also a hormone-dependent tumor. The expression of the apoptosis-related Bcl-2 and p53 genes, together with Ki67, E-cadherin, c-erb-B2 and estrogen and progesterone receptors were studied in 136 formalin-fixed, paraffin-embedded endometrial carcinoma samples by means of immunohistochemistry. Bcl-2 expression correlated directly and significantly with E-cadherin (r=0.22, p=0.011) estrogen receptor (r=0.18, p=0.04) and progesterone receptor expression (r=0.30, p=0.0006), and inversely with surgical stage (r=-0.20, p=0.024). Mutant p53 expression was directly and significantly associated with increasing patient age (r=0.25, p=0.007), tumor grade (r=0.37, pKi67 (r=0.47, pbreast cancer, apoptosis is hormonally regulated to some degree also in endometrial cancer.

  4. A light-up probe targeting for Bcl-2 2345 G-quadruplex DNA with carbazole TO

    Science.gov (United States)

    Gu, Yingchun; Lin, Dayong; Tang, Yalin; Fei, Xuening; Wang, Cuihong; Zhang, Baolian; Zhou, Jianguo

    2018-02-01

    As its significant role, the selective recognition of G-quadruplex with specific structures and functions is important in biological and medicinal chemistry. Carbazole derivatives have been reported as a kind of fluorescent probe with many excellent optical properties. In the present study, the fluorescence of the dye (carbazole TO) increased almost 70 fold in the presence of bcl-2 2345 G4 compared to that alone in aqueous buffer condition with almost no fluorescence and 10-30 fold than those in the presence of other DNAs. The binding study results by activity inhibition of G4/Hemin peroxidase experiment, NMR titration and molecular docking simulation showed the high affinity and selectivity to bcl-2 2345 G4 arises from its end-stacking interaction with G-quartet. It is said that a facile approach with excellent sensitive, good selectivity and quick response for bcl-2 2345 G-quadruplex was developed and may be used for antitumor recognition or antitumor agents.

  5. Spontaneous loss of B lineage transcription factors leads to pre-B leukemia in Ebf1+/-Bcl-xLTgmice.

    Science.gov (United States)

    Ramírez-Komo, J A; Delaney, M A; Straign, D; Lukin, K; Tsang, M; Iritani, B M; Hagman, J

    2017-07-10

    Early B-cell factor 1 (EBF1) plays a central role in B-cell lineage specification and commitment. Loss of this critical transcription factor is strongly associated with high-risk, relapsed and therapy-resistant B-cell-acute lymphoblastic leukemia, especially in children. However, Ebf1 haploinsufficient mice exhibit a normal lifespan. To determine whether prolonged survival of B cells would enable tumorigenesis in Ebf1 haploinsufficient animals, we generated Ebf1 +/- Bcl-x L Tg mice, which express the anti-apoptotic factor Bcl-x L in B cells. Approximately half of Ebf1 +/- Bcl-x L Tg mice develop aggressive oligoclonal leukemia as they age, which engrafts in congenic wild-type recipients without prior conditioning. The neoplastic cells display a pre-B phenotype and express early developmental- and natural killer cell/myeloid-markers inappropriately. In addition, we found tumor cell-specific loss of several transcription factors critical for maintaining differentiation: EBF1, TCF3 and RUNX1. However, in the majority of tumors, loss of Ebf1 expression was not due to loss of heterozygosity. This is the first spontaneous mouse model of pre-B leukemia to demonstrate inappropriate expression of non-B-cell-specific genes associated with loss of Ebf1, Tcf3 and Runx1 expression.

  6. Ultra-High-Throughput Screening of Natural Product Extracts to Identify Proapoptotic Inhibitors of Bcl-2 Family Proteins.

    Science.gov (United States)

    Hassig, Christian A; Zeng, Fu-Yue; Kung, Paul; Kiankarimi, Mehrak; Kim, Sylvia; Diaz, Paul W; Zhai, Dayong; Welsh, Kate; Morshedian, Shana; Su, Ying; O'Keefe, Barry; Newman, David J; Rusman, Yudi; Kaur, Harneet; Salomon, Christine E; Brown, Susan G; Baire, Beeraiah; Michel, Andrew R; Hoye, Thomas R; Francis, Subhashree; Georg, Gunda I; Walters, Michael A; Divlianska, Daniela B; Roth, Gregory P; Wright, Amy E; Reed, John C

    2014-09-01

    Antiapoptotic Bcl-2 family proteins are validated cancer targets composed of six related proteins. From a drug discovery perspective, these are challenging targets that exert their cellular functions through protein-protein interactions (PPIs). Although several isoform-selective inhibitors have been developed using structure-based design or high-throughput screening (HTS) of synthetic chemical libraries, no large-scale screen of natural product collections has been reported. A competitive displacement fluorescence polarization (FP) screen of nearly 150,000 natural product extracts was conducted against all six antiapoptotic Bcl-2 family proteins using fluorochrome-conjugated peptide ligands that mimic functionally relevant PPIs. The screens were conducted in 1536-well format and displayed satisfactory overall HTS statistics, with Z'-factor values ranging from 0.72 to 0.83 and a hit confirmation rate between 16% and 64%. Confirmed active extracts were orthogonally tested in a luminescent assay for caspase-3/7 activation in tumor cells. Active extracts were resupplied, and effort toward the isolation of pure active components was initiated through iterative bioassay-guided fractionation. Several previously described altertoxins were isolated from a microbial source, and the pure compounds demonstrate activity in both Bcl-2 FP and caspase cellular assays. The studies demonstrate the feasibility of ultra-high-throughput screening using natural product sources and highlight some of the challenges associated with this approach. © 2014 Society for Laboratory Automation and Screening.

  7. The BclI polymorphism of the glucocorticoid receptor gene is associated with emotional memory performance in healthy individuals.

    Science.gov (United States)

    Ackermann, Sandra; Heck, Angela; Rasch, Björn; Papassotiropoulos, Andreas; de Quervain, Dominique J-F

    2013-07-01

    Glucocorticoids, stress hormones released from the adrenal cortex, are important players in the regulation of emotional memory. Specifically, in animals and in humans, glucocorticoids enhance memory consolidation of emotionally arousing experiences, but impair memory retrieval. These glucocorticoid actions are partly mediated by glucocorticoid receptors in the hippocampus, amygdala and prefrontal cortex, key brain regions for emotional memory. In a recent study in patients who underwent cardiac surgery, the BclI polymorphism of the glucocorticoid receptor gene (NR3C1) was associated with traumatic memories and posttraumatic stress disorder symptoms after intensive care therapy. Based on this finding, we investigated if the BclI polymorphism is also associated with emotional memory in healthy young subjects (N=841). We used a picture-learning task consisting of learning and recalling neutral and emotional photographs on two consecutive days. The BclI variant was associated with short-delay recall of emotional pictures on both days, with GG carriers showing increased emotional memory performance as compared to GC and CC carriers. We did not detect a genotype-dependent difference in recall performance for neutral pictures. These findings suggest that the Bcll polymorphism contributes to inter-individual differences in emotional memory also in healthy humans. Copyright © 2012 Elsevier Ltd. All rights reserved.

  8. Hypoxia upregulates Bcl-2 expression and suppresses interferon-gamma induced antiangiogenic activity in human tumor derived endothelial cells.

    LENUS (Irish Health Repository)

    Wang, Jiang Huai

    2012-02-03

    BACKGROUND: Hypoxia in solid tumors potentially stimulates angiogenesis by promoting vascular endothelial growth factor (VEGF) production and upregulating VEGF receptor expression. However, it is unknown whether hypoxia can modulate the effect of anti-angiogenic treatment on tumor-derived endothelium. METHODS: Human tumor-derived endothelial cells (HTDEC) were freshly isolated from surgically removed human colorectal tumors by collagenase\\/DNase digestion and Percol gradient sedimentation. Cell proliferation was assessed by measuring BrdU incorporation, and capillary tube formation was measured using Matrigel. Cell apoptosis was assessed by flow cytometry and ELISA, and Bcl-2 expression was detected by Western blot analysis. RESULTS: Under aerobic culture conditions (5% CO2 plus 21% O2) HTDEC expressed less Bcl-2 and were more susceptible to IFN-gamma-induced apoptosis with significant reductions in both cell proliferation and capillary tube formation, when compared with normal human macrovascular and microvascular EC. Following exposure of HTDEC to hypoxia (5% CO2 plus 2% O2), IFN-gamma-induced cell apoptosis, and antiangiogenic activity (i.e. an inhibition in cell proliferation and capillary tube formation) in HTDEC were markedly attenuated. This finding correlated with hypoxia-induced upregulation of Bcl-2 expression in HTDEC. CONCLUSIONS: These results indicate that hypoxia can protect HTDEC against IFN-gamma-mediated cell death and antiangiogenic activity, and suggest that improvement of tumor oxygenation may potentiate the efficacy of anti-cancer therapies specifically targeting the inhibition of tumor angiogenesis.

  9. BCL9/9L-β-catenin Signaling is Associated With Poor Outcome in Colorectal Cancer

    Directory of Open Access Journals (Sweden)

    Andreas E. Moor

    2015-12-01

    Full Text Available BCL9/9L proteins enhance the transcriptional output of the β-catenin/TCF transcriptional complex and contribute critically to upholding the high WNT signaling level required for stemness maintenance in the intestinal epithelium. Here we show that a BCL9/9L-dependent gene signature derived from independent mouse colorectal cancer (CRC models unprecedentedly separates patient subgroups with regard to progression free and overall survival. We found that this effect was by and large attributable to stemness related gene sets. Remarkably, this signature proved associated with recently described poor prognosis CRC subtypes exhibiting high stemness and/or epithelial-to-mesenchymal transition (EMT traits. Consistent with the notion that high WNT signaling is required for stemness maintenance, ablating Bcl9/9l-β-catenin in murine oncogenic intestinal organoids provoked their differentiation and completely abrogated their tumorigenicity, while not affecting their proliferation. Therapeutic strategies aimed at targeting WNT responses may be limited by intestinal toxicity. Our findings suggest that attenuating WNT signaling to an extent that affects stemness maintenance without disturbing intestinal renewal might be well tolerated and prove sufficient to reduce CRC recurrence and dramatically improve disease outcome.

  10. Selective BCL-2 inhibition by ABT-199 causes on-target cell death in acute myeloid leukemia.

    Science.gov (United States)

    Pan, Rongqing; Hogdal, Leah J; Benito, Juliana M; Bucci, Donna; Han, Lina; Borthakur, Gautam; Cortes, Jorge; DeAngelo, Daniel J; Debose, Lakeisha; Mu, Hong; Döhner, Hartmut; Gaidzik, Verena I; Galinsky, Ilene; Golfman, Leonard S; Haferlach, Torsten; Harutyunyan, Karine G; Hu, Jianhua; Leverson, Joel D; Marcucci, Guido; Müschen, Markus; Newman, Rachel; Park, Eugene; Ruvolo, Peter P; Ruvolo, Vivian; Ryan, Jeremy; Schindela, Sonja; Zweidler-McKay, Patrick; Stone, Richard M; Kantarjian, Hagop; Andreeff, Michael; Konopleva, Marina; Letai, Anthony G

    2014-03-01

    B-cell leukemia/lymphoma 2 (BCL-2) prevents commitment to programmed cell death at the mitochondrion. It remains a challenge to identify those tumors that are best treated by inhibition of BCL-2. Here, we demonstrate that acute myeloid leukemia (AML) cell lines, primary patient samples, and murine primary xenografts are very sensitive to treatment with the selective BCL-2 antagonist ABT-199. In primary patient cells, the median IC50 was approximately 10 nmol/L, and cell death occurred within 2 hours. Our ex vivo sensitivity results compare favorably with those observed for chronic lymphocytic leukemia, a disease for which ABT-199 has demonstrated consistent activity in clinical trials. Moreover, mitochondrial studies using BH3 profiling demonstrate activity at the mitochondrion that correlates well with cytotoxicity, supporting an on-target mitochondrial mechanism of action. Our protein and BH3 profiling studies provide promising tools that can be tested as predictive biomarkers in any clinical trial of ABT-199 in AML.

  11. Placental apoptosis in preeclampsia, intrauterine growth retardation, and HELLP syndrome: an immunohistochemical study with caspase-3 and bcl-2.

    Science.gov (United States)

    Cali, U; Cavkaytar, S; Sirvan, L; Danisman, N

    2013-01-01

    To examine the placental expression of caspase-3 and bcl-2 in pregnancies complicated by preeclampsia, IUGR, and HELLP syndrome. A prospective case-control study was conducted on 50 pregnant women between December 2006 and August 2007 at Dr. Zekai Tahir Burak Women Health Research and Education Hospital, Ankara, Turkey. Placental tissue samples were obtained from 15 pregnancies complicated by preeclampsia, 15 pregnancies with normotensive IUGR, five pregnancies with HELLP syndrome, and 15 gestational age-matched normotensive pregnancies without intrauterine infection as a control group. The placental expression of caspase-3 and bcl-2 has been investigated by immunohistochemical staining. Caspase-3 immunostaining score was significantly higher in each group when compared with the control group (p = 0.002). However there was no statistically signifant difference with bcl-2 immunostaining in each group when compared with the control group. Apoptotic marker caspase-3 is significantly increased in the villous trophoblasts of patients with preeclampsia, HELLP syndrome, and IUGR indicating increased placental apoptosis.

  12. Ulipristal Acetate Inhibits Progesterone Receptor Isoform A-Mediated Human Breast Cancer Proliferation and BCl2-L1 Expression.

    Directory of Open Access Journals (Sweden)

    Nathalie Esber

    Full Text Available The progesterone receptor (PR with its isoforms and ligands are involved in breast tumorigenesis and prognosis. We aimed at analyzing the respective contribution of PR isoforms, PRA and PRB, in breast cancer cell proliferation in a new estrogen-independent cell based-model, allowing independent PR isoforms analysis. We used the bi-inducible human breast cancer cell system MDA-iPRAB. We studied the effects and molecular mechanisms of action of progesterone (P4 and ulipristal acetate (UPA, a new selective progesterone receptor modulator, alone or in combination. P4 significantly stimulated MDA-iPRA expressing cells proliferation. This was associated with P4-stimulated expression of the anti-apoptotic factor BCL2-L1 and enhanced recruitment of PRA, SRC-1 and RNA Pol II onto the +58 kb PR binding motif of the BCL2-L1 gene. UPA decreased cell proliferation and repressed BCL2-L1 expression in the presence of PRA, correlating with PRA and SRC1 but not RNA Pol II recruitment. These results bring new information on the mechanism of action of PR ligands in controlling breast cancer cell proliferation through PRA in an estrogen independent model. Evaluation of PR isoforms ratio, as well as molecular signature studies based on PRA target genes could be proposed to facilitate personalized breast cancer therapy. In this context, UPA could be of interest in endocrine therapy. Further confirmation in the clinical setting is required.

  13. Suppression of chondrosarcoma cells by 15-deoxy-Δ12,14-prostaglandin J2 is associated with altered expression of Bax/Bcl-xL and p21

    International Nuclear Information System (INIS)

    Shen, Zheng-Nan; Nishida, Keiichiro; Doi, Hideyuki; Oohashi, Toshitaka; Hirohata, Satoshi; Ozaki, Toshifumi; Yoshida, Aki; Ninomiya, Yoshifumi; Inoue, Hajime

    2005-01-01

    We previously reported that 15-deoxy-Δ 12,14 -prostaglandin J 2 (15d-PGJ 2 ), the most potent agonist for peroxisome proliferator-activated receptor γ (PPARγ), induces apoptosis of human chondrosarcoma cell line OUMS-27. The current study aimed to explore the mechanism of 15d-PGJ 2 -induced apoptosis and inhibition of cell proliferation in OUMS-27 cells. The preliminary results of cDNA microarray analysis showed the down-regulation of anti-apoptotic Bcl-xL and up-regulation of pro-apoptotic Bax in the process of 15d-PGJ 2 -induced apoptosis. These changes were further confirmed at mRNA and protein levels by RT-PCR and Western blot analysis, respectively. Among cyclin-dependent kinase inhibitors, p21 was induced and up-regulated by 15d-PGJ 2 , but p16 and p27 were not changed, suggesting that the involvement of p21 in inhibition of cell proliferation. Activation of caspase-3 by 15d-PGJ 2 was partly, but not completely, blocked by PPARγ antagonist (GW9662) suggesting the 15d-PGJ 2 exerted its effect by PPARγ-dependent and -independent pathways. Interestingly, immunohistochemical study on human chondrosarcoma samples revealed that Bcl-xL is frequently expressed by tumor cells. The results of the current study suggest that the potential ability of 15d-PGJ 2 in regulation of cell cycle and inhibition of Bcl-xL expression might be beneficial in the development of novel pharmacological agents for chondrosarcoma

  14. B1-induced caspase-independent apoptosis in MCF-7 cells is mediated by down-regulation of Bcl-2 via p53 binding to P2 promoter TATA box

    International Nuclear Information System (INIS)

    Liang Xin; Xu Ke; Xu Yufang; Liu Jianwen; Qian Xuhong

    2011-01-01

    The Bcl-2 family contains a panel of proteins which are conserved regulators of apoptosis in mammalian cells, like the anti-apoptotic protein Bcl-2. According to its significant role in altering susceptibility to apoptosis, the deciphering of the mechanism of Bcl-2 expression modulation may be crucial for identifying therapeutics strategies for cancer. Treatment with naphthalimide-based DNA intercalators, including M2-A and R16, generally leads to a decrease in Bcl-2 intracellular amounts. Whereas the interest for these chemotherapeutics is accompanied by advances in the fundamental understanding of their anticancer properties, the molecular mechanism underlying changes in Bcl-2 expression remains poorly understood. We report here that p53 contributes to Bcl-2 down-regulation induced by B1, a novel naphthalimide-based DNA intercalating agent. Indeed, the decrease in Bcl-2 protein levels observed during B1-induced apoptosis was correlated to the decrease in mRNA levels, as a result of the inhibition of Bcl-2 transcription and promoter activity. In this context, we evaluated p53 contribution in the Bcl-2 transcriptional down-regulation. We found a significant increase of p53 binding to P 2 promoter TATA box in MCF7 cells by chromatin immunoprecipitation. These data suggest that B1-induced caspase-independent apoptosis in MCF-7 cells is associated with the activation of p53 and the down-regulation of Bcl-2. Our study strengthens the links between p53 and Bcl-2 at a transcriptional level, upon naphthalimide-based DNA intercalator treatment. - Research highlights: → B1 induced apoptosis in MCF-7 cells, following a transcriptional decrease in Bcl-2. → B1 treatment triggered p53 activation and leads to a p53-dependent down-regulation of Bcl-2. → B1 induced significant increase of p53 binding to Bcl-2 P 2 promoter TATA box.

  15. Bcl-2 and bax expression and prostate cancer outcome in men treated with radiotherapy in Radiation Therapy Oncology Group protocol 86-10

    International Nuclear Information System (INIS)

    Khor, L.-Y.; De Silvio, Michelle; Li, Rile; McDonnell, Timothy J.; Hammond, M. Elizabeth H.; Sause, William T.; Pilepich, Miljenko V.; Okunieff, Paul; Sandler, Howard M.; Pollack, Alan

    2006-01-01

    Purpose: Bcl-2 and bax are proteins with opposing roles in apoptosis regulation; yet abnormal expression of either has been associated with failure after radiotherapy (RT). In this study we examined bcl-2 and bax expression as predictive markers in men treated with radiotherapy ± androgen deprivation on Radiation Therapy Oncology Group (RTOG) protocol 86-10. Experimental Design: Suitable archival diagnostic tissue was obtained from 119 (26%) patients for bcl-2 analysis and 104 (23%) patients for bax analysis. Cox proportional hazards multivariate analysis was used to determine the relationship of abnormal bcl-2 and bax expression to the end points of local failure, distant metastasis, cause-specific mortality, and overall mortality. Bcl-2 overexpression was classified as any tumor cell cytoplasmic staining and altered bax expression was classified as greater or lesser cytoplasmic staining intensity of tumor cells as compared with adjacent normal prostate epithelium. Results: The study cohort exhibited bcl-2 overexpression in 26% (n = 30) of cases and abnormal bax expression in 47% (n = 49) of cases. A borderline significant relationship was observed between abnormal bax expression and higher Gleason score (p = 0.08). In univariate and multivariate analyses, there was no statistically significant relationship seen between abnormal bcl-2 or bax expression and outcome. Conclusions: Abnormal bcl-2 and bax expression were not related to any of the end points tested. The cohort examined was comprised of patients with locally advanced disease and it is possible that these markers may be of greater value in men with earlier-stage prostate cancer

  16. Experimental pneumococcal meningitis: impaired clearance of bacteria from the blood due to increased apoptosis in the spleen in Bcl-2-deficient mice.

    Science.gov (United States)

    Wellmer, Andreas; von Mering, Matthias; Spreer, Annette; Diem, Ricarda; Eiffert, Helmut; Noeske, Christiane; Bunkowski, Stefanie; Gold, Ralf; Nau, Roland

    2004-06-01

    Necrotic and apoptotic neuronal cell death can be found in pneumococcal meningitis. We investigated the role of Bcl-2 as an antiapoptotic gene product in pneumococcal meningitis using Bcl-2 knockout (Bcl-2(-/-)) mice. By using a model of pneumococcal meningitis induced by intracerebral infection, Bcl-2-deficient mice and control littermates were assessed by clinical score and a tight rope test at 0, 12, 24, 32, and 36 h after infection. Then mice were sacrificed, the bacterial titers in blood, spleen, and cerebellar homogenates were determined, and the brain and spleen were evaluated histologically. The Bcl-2-deficient mice developed more severe clinical illness, and there were significant differences in the clinical score at 24, 32, and 36 h and in the tight rope test at 12 and 32 h. The bacterial titers in the blood were greater in Bcl-2-deficient mice than in the controls (7.46 +/- 1.93 log CFU/ml versus 5.16 +/- 0.96 log CFU/ml [mean +/- standard deviation]; P < 0.01). Neuronal damage was most prominent in the hippocampal formation, but there were no significant differences between groups. In situ tailing revealed only a few apoptotic neurons in the brain. In the spleen, however, there were significantly more apoptotic leukocytes in Bcl-2-deficient mice than in controls (5,148 +/- 3,406 leukocytes/mm2 versus 1,070 +/- 395 leukocytes/mm2; P < 0.005). Bcl-2 appears to counteract sepsis-induced apoptosis of splenic lymphocytes, thereby enhancing clearance of bacteria from the blood.

  17. [Apoptosis-modulating effects of heat shock proteins: the influence of Hsp27 chaperone on TBA Bcl-2 family proteins in Jurkat cell line].

    Science.gov (United States)

    Riazantseva, N V; Kaĭgorodova, E V; Maroshkina, A N; Belkina, M V; Novitskiĭ, V V

    2012-01-01

    The in vitro phosphorylated and non-phosphorylated Hsp27 forms concentrations and Bcl-2 proteins affected by Hsp27 inhibition were studied in Jurkat-line tumor cells and healthy donor mononuclear lymphocytes by Western blotting technique. The Hsp27 inhibition causes the increase of intracellular Bax protein concentration and the decrease of Bcl-2 level leading to an increase of apoptotic changes in Jurkat line cells.

  18. Effect of doxorubicin, oxaliplatin, and methotrexate administration on the transcriptional activity of BCL-2 family gene members in stomach cancer cells.

    Science.gov (United States)

    Florou, Dimitra; Patsis, Christos; Ardavanis, Alexandros; Scorilas, Andreas

    2013-07-01

    Defective apoptosis comprises the main reason for tumor aggressiveness and chemotherapy tolerance in solid neoplasias. Among the BCL-2 family members, whose mRNA or protein expression varies considerably in different human malignancies, BCL2L12 is the one for which we have recently shown its propitious prognostic value in gastric cancer. The purpose of the current work was to investigate the expression behavior of BCL2L12, BAX, and BCL-2 in human stomach adenocarcinoma cells following their exposure to anti-tumor substances. The 3-(4,5-dimethyl thiazol-2-yl)-2,5-diphenyl tetrazolium bromide and trypan blue methods assessed the impact of doxorubicin, oxaliplatin and methotrexate on AGS cells' viability and growth. Following isolation from cells, total RNA was reverse-transcribed to cDNA. Quantification of target genes' expression was performed with real-time PCR using SYBR Green detection system. The relative changes in their mRNA levels between drug-exposed and untreated cells were calculated with the comparative Ct method (2(-ddCt)). All three drugs, as a result of their administration to AGS cancer cells for particular time intervals, provoked substantial fluctuations in the transcriptional levels of the apoptosis-related genes studied. While BAX was principally upregulated, striking similar were the notable changes regarding BCL-2 and BCL2L12 expression in our cellular system. Our findings indicate the growth suppressive effects of doxorubicin, oxaliplatin and methotrexate treatment on stomach carcinoma cells and the implication of BCL2L12, BAX, and BCL-2 expression profiles in the molecular signaling pathways triggered by chemotherapy.

  19. The significance of expression of autophagy-related gene Beclin, Bcl-2, and Bax in breast cancer tissues.

    Science.gov (United States)

    Yao, Qing; Chen, Jianghao; Lv, Yonggang; Wang, Ting; Zhang, Juliang; Fan, Jing; Wang, Ling

    2011-12-01

    The purpose of this study was to detect the expression of autophagy-related gene Beclin1 and apoptosis-related genes Bcl-2 and Bax in breast cancer tissues, to investigate their relationship and significance to the occurrence and development of breast cancer, and to provide an experimental basis for the biological treatment of breast cancer in the future. Human breast cancer tissues and relatively healthy breast tissue adjacent to the tumor were collected during surgical resection. By using RT-PCR and western blot, the mRNA and protein expressions of Beclin1, Bcl-2, and Bax were detected in the breast cancer tissues and the relatively healthy, adjacent tissues. The correlations of these expressions with the occurrence, development, and clinicopathology of breast cancer were analyzed. The mRNA and protein expressions of Beclin1 and Bcl-2 in breast cancer tissues were significantly lower than those in the relatively healthy, adjacent breast tissues (p breast cancer tissues from patients positive for lymph node metastasis were significantly lower than those negative for lymph node metastasis (p breast cancer tissues from patients positive for distant metastasis were significantly lower than those negative for distant metastasis (p breast cancer tissues from patients positive for ki67 were significantly lower than those negative for ki67 (p breast cancer tissues, the mRNA and protein expressions of Bax were up-regulated (p breast cancer tissues from patients positive for lymph node metastasis were significantly higher than those negative for lymph node metastasis (p breast cancer tissues from patients positive for distant metastasis were significantly higher than those in patients negative for distant metastasis (p  0.05). The correlation of Bcl-2 and Bax mRNA with Beclin1 mRNA expressed in breast cancer tissues were both statistically significant (p apoptosis is associated with the tumorigenesis and tumor progression of breast cancer. The joint

  20. Enhanced transient recombinant protein production in CHO cells through the co-transfection of the product gene with Bcl-xL

    Science.gov (United States)

    Zustiak, Matthew P.; Jose, Lisa; Xie, Yueqing; Zhu, Jianwei; Betenbaugh, Micheal J.

    2014-01-01

    Transient gene expression is gaining popularity as a method to rapidly produce recombinant proteins in mammalian cells. Although significant improvements have been made, in terms of expression, more improvements are needed to compete with the yields achievable in stable gene expression. Much progress has come from optimization of transfection media and parameters, as well as altering culturing conditions to enhance productivity. Recent studies have included using cell lines engineered for apoptosis resistance through the constitutive expression of an anti-apoptotic protein, Bcl-xL. In this study we examine an alternative method of using the benefits of anti-apoptotic gene expression to enhance the transient expression of biotherapeutics, namely, through the co-transfection of bcl-xL and the product-coding gene. CHO-S cells were co-transfected with the product-coding gene and a vector containing Bcl-xL using polyethylenimine. Cells co-transfected with Bcl-xL showed reduced levels of apoptosis, increased specific productivity, and an overall increase in product yield of approximately 100%. Similar results were produced by employing another anti-apoptotic protein, Bcl-2 delta in CHO cells, or through the co-transfection with bcl-xL using HEK-293E cells. This work provides an alternative method for increasing yields of therapeutic proteins in TGE applications without generating a prior stable cell line and subsequent screening which are both time and resource consuming. PMID:24604826

  1. Expression, purification and characterization of hepatitis B virus X protein BH3-like motif-linker-Bcl-xL fusion protein for structural studies

    Directory of Open Access Journals (Sweden)

    Hideki Kusunoki

    2017-03-01

    Full Text Available Hepatitis B virus X protein (HBx is a multifunctional protein that interacts directly with many host proteins. For example, HBx interacts with anti-apoptotic proteins, Bcl-2 and Bcl-xL, through its BH3-like motif, which leads to elevated cytosolic calcium levels, efficient viral DNA replication and the induction of apoptosis. To facilitate sample preparation and perform detailed structural characterization of the complex between HBx and Bcl-xL, we designed and purified a recombinant HBx BH3-like motif-linker-Bcl-xL fusion protein produced in E. coli. The fusion protein was characterized by size exclusion chromatography, circular dichroism and nuclear magnetic resonance experiments. Our results show that the fusion protein is a monomer in aqueous solution, forms a stable intramolecular complex, and likely retains the native conformation of the complex between Bcl-xL and the HBx BH3-like motif. Furthermore, the HBx BH3-like motif of the intramolecular complex forms an α-helix. These observations indicate that the fusion protein should facilitate structural studies aimed at understanding the interaction between HBx and Bcl-xL at the atomic level.

  2. High level of Bcl-2 counteracts apoptosis mediated by a live rabies virus vaccine strain and induces long-term infection

    International Nuclear Information System (INIS)

    Thoulouze, Maria-Isabel; Lafage, Mireille; Yuste, Victor J.; Baloul, Leiela; Edelman, Lena; Kroemer, Guido; Israel, Nicole; Susin, Santos A.; Lafon, Monique

    2003-01-01

    We report here that rabies virus strains, currently used to immunize wildlife against rabies, induce not only caspase-dependent apoptosis in the human lymphoblastoid Jurkat T cell line (Jurkat-vect), but also a caspase-independent pathway involving the apoptosis-inducing factor (AIF). In contrast, a strain of neurotropic RV that does not induce apoptosis did not activate caspases or induce AIF translocation. Bcl-2 overproduction in Jurkat T cells (Jurkat-Bcl-2) abolished both pathways. ERA infection and production were similar in Jurkat-vect and Jurkat-Bcl-2 cells, indicating Bcl-2 has no direct antiviral effects. Bcl-2 production is naturally upregulated by day 3 in ERA-infected Jurkat-vect cultures. The increase in Bcl-2 levels seems to be controlled by the virus infection itself and results in the establishment of long-term, persistently infected cultures that continue to produce virus. Thus, in infections with live RV vaccine strains, infected cells may be productive reservoirs of virus in the long term. This may account for the high efficacy of live rabies vaccines

  3. Effect of bcl-2 antisense oligodexynucleotides on chemotherapy efficacy of Vp-16 on human small cell lung cancer cell line NCI-H69

    International Nuclear Information System (INIS)

    He Wenqian; Liu Zhonghua

    2007-01-01

    Objective: To study the effect of bcl-2 antisense oligodexynucleotides on chemotherapy efficacy of Vp-16 on human small cell lung cancer cell line NCI-H69. Methods: Cultured NCI-H69 cells were derided into 4 groups: bcl-2 antisense oligodexynucleotides (ASODN) added, sense oligodexynucleotides (SODN) added, nonsense oligodexynucleotides (NSODN) added and control (no nucleotides added), the oligodexynucleotides were transfected into the cultured cells with oligofectamine. The cellular expression of Bcl-2 protein 72h later was examined with Western-Blot. The four different groups of cultured tumor cells were treated with etopside(Vp-16) at different concentrations (0, 0.25, 0.5, 1.0, 2.0 and 4.0 μg/ml) for 48hr then the cell survival fraction was assessed with MTY test. Results: The apoptotic rate of cells in the ASODN group was significantly higher than that of the control group, also, the survival fraction of cells in ASODN group was significantly lower than that of the control group. The Bcl-2 protein expression in ASODN group was significantly lower than that in the control group, but no inhibition was observed in SODN and NSODN groups. Conclusion: The bcl-2 ASODN could enhance the sensitivity to chemotherapy with Vp-16 in small cell lung cancer cell line NCI-H69 by effectively blocking bcl-2 gene expression. (authors)

  4. Effects of Xenoestrogens on T Lymphocytes: Modulation of bcl-2, p53, and Apoptosis

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    Robert W. McMurray

    2003-01-01

    Full Text Available Abstract: Endogenous estrogens have significant immunomodulatory effects characterized as suppression of cell mediated immunity and stimulation of humoral immunity. Xenoestrogens are environmental estrogens that have endocrine impact, acting as estrogen agonists and antagonists but whose immune effects are not well characterized. Using CD4+ Jurkat T cells as a model, the effects of representative xenoestrogens on T proliferation, cell cycle, and apoptosis were examined. Coumestrol (CM, a phytoestrogen, and tetrachlorodioxin (TCDD in concentrations of 10-4 to 10-6M significantly inhibited Jurkat T cell lymphoproliferation, whereas bisphenol A (BPA and DDT had minimal effect, but did antagonize 17-β-estrtadiol induced effects. Xenoestrogens, especially CM, produced accumulation of Jurkat T cells in G2/M phase, and subsequently induced apoptosis, particularly CM (% apoptotic cells = 30 ± 12 vs. control = 5 ± 2. These changes were associated with DNA fragmentation. BPA and DDT also induced DNA fragmentation but not significant DNA hypoploidy. Xenoestrogen – CM, BPA, DDT, and TCDD - exposure suppressed bcl-2 protein and mRNA transcript levels but augmented p53 protein and mRNA transcripts. Human purified peripheral blood lymphocytes responded with similar significant cell cycle changes (G0/G1 exodus and G2/M accumulation for CM, BPA, and DDT exposure. These preliminary data, taken together, suggest that xenoestrogens have direct, compound-specific T lymphocyte effects that enhance our understanding of environmental modulation of immune and autoimmune responses.

  5. IRES-mediated translation of the pro-apoptotic Bcl2 family member PUMA

    Science.gov (United States)

    Shaltouki, Atossa; Harford, Terri J.; Komar, Anton A.; Weyman, Crystal M.

    2013-01-01

    The proapoptotic Bcl-2 family member PUMA is a critical regulator of apoptosis. We have previously shown that PUMA plays a pivotal role in the apoptosis associated with skeletal myoblast differentiation and that a MyoD-dependent mechanism is responsible for the increased expression of PUMA in these cells. Herein, we report that the increased expression of PUMA under these conditions involves regulation at the level of translation. Specifically, we have found that the increase in PUMA protein levels occurs under conditions of decreased total protein synthesis, eIF2-alpha phosphorylation and hypophosphorylation of eIF4E-BP, suggesting that PUMA translation is proceeding via an alternative initiation mechanism. Polyribosome analysis of PUMA mRNA further corroborated this suggestion. A combination of in vitro and ex vivo (cellular) approaches has provided evidence suggesting that PUMA mRNA 5'UTR harbors an Internal Ribosome Entry Site (IRES) element. Using mono- and bi-cistronic reporter constructs, we have delineated an mRNA fragment that allows for cap-independent translation in vitro and ex vivo (in skeletal myoblasts) in response to culture in differentiation media (DM), or in response to treatment with the DNA-damaging agent, etoposide. This mRNA fragment also supports translation in HeLa and 293T cells. Thus, our data has revealed a novel IRES-mediated regulation of PUMA expression in several cell types and in response to several stimuli. These findings contribute to our understanding and potential manipulation of any developmental or therapeutic scenario involving PUMA. PMID:26824017

  6. Bcl-2–associated athanogene 3 protects the heart from ischemia/reperfusion injury

    Science.gov (United States)

    Su, Feifei; Myers, Valerie D.; Knezevic, Tijana; Wang, JuFang; Gao, Erhe; Madesh, Muniswamy; Tahrir, Farzaneh G.; Gupta, Manish K.; Gordon, Jennifer; Rabinowitz, Joseph; Tilley, Douglas G.; Khalili, Kamel; Cheung, Joseph Y.

    2016-01-01

    Bcl-2–associated athanogene 3 (BAG3) is an evolutionarily conserved protein expressed at high levels in the heart and the vasculature and in many cancers. While altered BAG3 expression has been associated with cardiac dysfunction, its role in ischemia/reperfusion (I/R) is unknown. To test the hypothesis that BAG3 protects the heart from reperfusion injury, in vivo cardiac function was measured in hearts infected with either recombinant adeno-associated virus serotype 9–expressing (rAAV9-expressing) BAG3 or GFP and subjected to I/R. To elucidate molecular mechanisms by which BAG3 protects against I/R injury, neonatal mouse ventricular cardiomyocytes (NMVCs) in which BAG3 levels were modified by adenovirus expressing (Ad-expressing) BAG3 or siBAG3 were exposed to hypoxia/reoxygenation (H/R). H/R significantly reduced NMVC BAG3 levels, which were associated with enhanced expression of apoptosis markers, decreased expression of autophagy markers, and reduced autophagy flux. The deleterious effects of H/R on apoptosis and autophagy were recapitulated by knockdown of BAG3 with Ad-siBAG3 and were rescued by Ad-BAG3. In vivo, treatment of mice with rAAV9-BAG3 prior to I/R significantly decreased infarct size and improved left ventricular function when compared with mice receiving rAAV9-GFP and improved markers of autophagy and apoptosis. These findings suggest that BAG3 may provide a therapeutic target in patients undergoing reperfusion after myocardial infarction. PMID:27882354

  7. Reactivating Fetal Hemoglobin Expression in Human Adult Erythroblasts Through BCL11A Knockdown Using Targeted Endonucleases

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    Carmen F Bjurström

    2016-01-01

    Full Text Available We examined the efficiency, specificity, and mutational signatures of zinc finger nucleases (ZFNs, transcriptional activator-like effector nucleases (TALENs, and clustered regularly interspaced short palindromic repeat (CRISPR/Cas9 systems designed to target the gene encoding the transcriptional repressor BCL11A, in human K562 cells and human CD34+ progenitor cells. ZFNs and TALENs were delivered as in vitro transcribed mRNA through electroporation; CRISPR/Cas9 was codelivered by Cas9 mRNA with plasmid-encoded guideRNA (gRNA (pU6.g1 or in vitro transcribed gRNA (gR.1. Analyses of efficacy revealed that for these specific reagents and the delivery methods used, the ZFNs gave rise to more allelic disruption in the targeted locus compared to the TALENs and CRISPR/Cas9, which was associated with increased levels of fetal hemoglobin in erythroid cells produced in vitro from nuclease-treated CD34+ cells. Genome-wide analysis to evaluate the specificity of the nucleases revealed high specificity of this specific ZFN to the target site, while specific TALENs and CRISPRs evaluated showed off-target cleavage activity. ZFN gene-edited CD34+ cells had the capacity to engraft in NOD-PrkdcSCID-IL2Rγnull mice, while retaining multi-lineage potential, in contrast to TALEN gene-edited CD34+ cells. CRISPR engraftment levels mirrored the increased relative plasmid-mediated toxicity of pU6.g1/Cas9 in hematopoietic stem/progenitor cells (HSPCs, highlighting the value for the further improvements of CRISPR/Cas9 delivery in primary human HSPCs.

  8. Inhibition of Bcl-2 or IAP proteins does not provoke mutations in surviving cells

    Energy Technology Data Exchange (ETDEWEB)

    Shekhar, Tanmay M. [Department of Biochemistry, La Trobe Institute for Molecular Science, La Trobe University, Bundoora 3083 (Australia); Green, Maja M. [Department of Biochemistry, La Trobe Institute for Molecular Science, La Trobe University, Bundoora 3083 (Australia); Department of Anatomy & Neuroscience, The University of Melbourne, Parkville 3010 (Australia); Rayner, David M.; Miles, Mark A.; Cutts, Suzanne M. [Department of Biochemistry, La Trobe Institute for Molecular Science, La Trobe University, Bundoora 3083 (Australia); Hawkins, Christine J., E-mail: c.hawkins@latrobe.edu.au [Department of Biochemistry, La Trobe Institute for Molecular Science, La Trobe University, Bundoora 3083 (Australia)

    2015-07-15

    Graphical abstract: - Highlights: • Mutagenicities of anti-cancer drugs were tested using HPRT, γH2AX and comet assays. • TRAIL, doxorubicin and etoposide were more mutagenic than BH3- or Smac-mimetics. • Physiologically achievable levels of the BH3-mimetic ABT-737 were not mutagenic. • High concentrations of ABT-737 provoked mutations via an off-target mechanism. • Even very high concentrations of IAP antagonists were not mutagenic. - Abstract: Chemotherapy and radiotherapy can cause permanent damage to the genomes of surviving cells, provoking severe side effects such as second malignancies in some cancer survivors. Drugs that mimic the activity of death ligands, or antagonise pro-survival proteins of the Bcl-2 or IAP families have yielded encouraging results in animal experiments and early phase clinical trials. Because these agents directly engage apoptosis pathways, rather than damaging DNA to indirectly provoke tumour cell death, we reasoned that they may offer another important advantage over conventional therapies: minimisation or elimination of side effects such as second cancers that result from mutation of surviving normal cells. Disappointingly, however, we previously found that concentrations of death receptor agonists like TRAIL that would be present in vivo in clinical settings provoked DNA damage in surviving cells. In this study, we used cell line model systems to investigate the mutagenic capacity of drugs from two other classes of direct apoptosis-inducing agents: the BH3-mimetic ABT-737 and the IAP antagonists LCL161 and AT-406. Encouragingly, our data suggest that IAP antagonists possess negligible genotoxic activity. Doses of ABT-737 that were required to damage DNA stimulated Bax/Bak-independent signalling and exceeded concentrations detected in the plasma of animals treated with this drug. These findings provide hope that cancer patients treated by BH3-mimetics or IAP antagonists may avoid mutation-related illnesses that afflict

  9. Lycopene Extracts from Different Tomato-Based Food Products Induce Apoptosis in Cultured Human Primary Prostate Cancer Cells and Regulate TP53, Bax and Bcl-2 Transcript Expression

    Science.gov (United States)

    Soares, Nathalia da Costa Pereira; Machado, Clara Lima; Trindade, Bruno Boquimpani; Lima, Ingridy Celestino do Canto; Gimba, Etel Rodrigues Pereira; Teodoro, Anderson Junger; Takiya, Christina; Borojevic, Radovan

    2017-01-01

    Carotenoids are the main tomato components, especially lycopene. Lycopene is more bioavailable in tomato processed products than in raw tomatos, since formation of lycopene cis-isomers during food processing and storage may increase its biological activity. In the current study, we evaluated the influence of lycopene extracts (5 mg / mL) from different tomato-based food products (paste, sauce, extract and ketchup) on cell viability and apoptosis on primary human prostate cancer cells (PCa cels) for 96h. Using MTT assay, we observed a significant decrease on primary PCa cell viability upon treatment with lycopene extracted from either 4 tomato-based food products. Flow cytometeric analysis revealed that lycopene from tomato extract and tomato sauce promoted up to fifty-fold increase on the proportion of apoptotic cells, when compared to the control group. Using real time PCR assay, we found that lycopene promoted an upregulation of TP53 and Bax transcript expression and also downregulation of Bcl-2 expression in PCa cells. In conclusion, our data demostrate that cis-lycopene promoted a significant inhibition on primary PCa cell viability, as well as an increase on their apoptotic rates, evidencing that cis-lycopene contained in tomato sauce and extract cain mainly modulate of primary human prostate cancer cell survival. PMID:28345329

  10. Immunohistochemical expression of p53, BCL-2, BAX and VEGFR1 proteins in nephroblastomas A expressão imuno-histoquímica das proteínas p53, BCL-2, BAX e VEGFR1 em nefroblastomas

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    Ana Paula Percicote

    2013-02-01

    Full Text Available INTRODUCTION: Nephroblastoma or Wilms' tumor is the most frequent renal cancer in children. Although its prognosis is favorable for most patients, it may relapse or have a fatal outcome. The characterization of risk groups by applying immunohistochemical biomarkers aims to adapt the treatment to its corresponding group as well as to reduce relapses and fatal outcome. p53, B-cell lymphoma 2 (BCL-2, BCL-2 associated protein X (BAX and vascular endothelial growth factor receptor 1 (VEGFR1 are among the most widely studied biomarkers, which are related to the apoptotic pathway, DNA repair and neovascularization. OBJECTIVE: The objective of this study is to assess the immunohistochemical expression of p53, BCL-2, BAX and VEGFR1 in samples of human nephroblastoma and to correlate them with clinicopathological prognostic factors. MATERIAL AND METHODS: Twenty-nine surgical specimens of nephroblastoma diagnosed from 1994 to 2007 were selected from the Anatomopathological Service of two hospitals in Curitiba. The immunohistochemical analysis of tissue microarrays was performed through immunoperoxidase staining and the yielded results were compared with clinicopathological prognostic factors. RESULTS: The major immunohistochemical expression of VEGFR1 in blastema and epithelium presented positive association with the risk group. Hence this may be related to higher vascular neoplastic invasion apparently caused by the endothelial growth factor, which maximizes the chances of metastasis and ultimately changes tumor staging, risk group and clinical evolution. CONCLUSIONS: The immunohistochemical expression of VEGFR1 substantiated a directly proportional association with the nephroblastoma risk group.INTRODUÇÃO: O nefroblastoma, ou tumor de Wilms, é a neoplasia renal mais frequente na infância. Embora o prognóstico seja favorável para a maioria dos pacientes, muitos evoluem para recidiva ou óbito. A caracterização de grupos de risco por meio de

  11. Synergistic and complete reversal of the multidrug resistance of mitoxantrone hydrochloride by three-in-one multifunctional lipid-sodium glycocholate nanocarriers based on simultaneous BCRP and Bcl-2 inhibition.

    Science.gov (United States)

    Ling, Guixia; Zhang, Tianhong; Zhang, Peng; Sun, Jin; He, Zhonggui

    Multidrug resistance (MDR) is a severe obstacle to successful chemotherapy due to its complicated nature that involves multiple mechanisms, such as drug efflux by transporters (P-glycoprotein and breast cancer resistance protein, BCRP) and anti-apoptotic defense (B-cell lymphoma, Bcl-2). To synergistically and completely reverse MDR by simultaneous inhibition of pump and non-pump cellular resistance, three-in-one multifunctional lipid-sodium glycocholate (GcNa) nanocarriers (TMLGNs) have been designed for controlled co-delivery of water-soluble cationic mitoxantrone hydrochloride (MTO), cyclosporine A (CsA - BCRP inhibitor), and GcNa (Bcl-2 inhibitor). GcNa and dextran sulfate were incorporated as anionic compounds to enhance the encapsulation efficiency of MTO (up to 97.8%±1.9%) and sustain the release of cationic MTO by electrostatic interaction. The results of a series of in vitro and in vivo investigations indicated that the TMLGNs were taken up by the resistant cancer cells by an endocytosis pathway that escaped the efflux induced by BCRP, and the simultaneous release of CsA with MTO further efficiently inhibited the efflux of the released MTO by BCRP; meanwhile GcNa induced the apoptosis process, and an associated synergistic antitumor activity and reversion of MDR were achieved because the reversal index was almost 1.0.

  12. Maternal exposure to titanium dioxide nanoparticles during pregnancy and lactation alters offspring hippocampal mRNA BAX and Bcl-2 levels, induces apoptosis and decreases neurogenesis.

    Science.gov (United States)

    Ebrahimzadeh Bideskan, Alireza; Mohammadipour, Abbas; Fazel, Alireza; Haghir, Hossein; Rafatpanah, Houshang; Hosseini, Mahmoud; Rajabzadeh, Aliakbar

    2017-07-05

    The usage of Titanium dioxide nanoparticles (TiO 2 -NPs) covers a vast area in different fields ranging from cosmetics and food to the production of drugs. Maternal exposure to TiO 2 -NPs during developmental period has been associated with hippocampal injury and with a decrease in learning and memory status of the offspring. However, little is known about its injury mechanism. This paper describes the in vivo neurotoxic effects of TiO 2 -NPs on rat offspring hippocampus during developmental period. Pregnant and lactating Wistar rats received intragastric TiO 2 -NPs (100mg/kg body weight) daily from gestational day (GD) 2 to (GD) 21 and postnatal day (PD) 2 to (PD) 21 respectively. Animals in the control groups received an equal volume of distilled water via gavage. At the end of the treatment process, offspring were deeply anesthetized and sacrificed. Then brains of each group were collected and sections of the rat offspring's brains were stained using TUNEL staining (for detection of apoptotic cells) and immunostaining (for neurogenesis). Moreover, the right hippocampus (n=6 per each group) were removed from the right hemisphere for evaluating the expression of Bax and Bcl-2 level. Results of histopatological examination by TUNEL staining showed that maternal exposure to TiO 2 -NPs during pregnancy and lactation periods increased apoptotic cells significantly (P<0.01) in the offspring hippocampus. The immunolabeling of double cortin (DCX) protein as neurogenesis marker also showed that TiO 2 -NPs reduced neurogenesis in the hippocampus of the offspring (P<0.05). Moreover, in comparison with the control group, the mRNA levels of Bax and Bcl-2 in the TiO 2 -NPs group significantly increased and decreased, respectively (P<0.01). These findings provide strong evidence that maternal exposure to TiO 2 -NPs significantly impact hippocampal neurogenesis and apoptosis in the offspring. The potential impact of nanoparticle exposure for millions of pregnant mothers and

  13. p53, cathepsin D, Bcl-2 are joint prognostic indicators of breast cancer metastatic spreading.

    Science.gov (United States)

    Guerra, Emanuela; Cimadamore, Alessia; Simeone, Pasquale; Vacca, Giovanna; Lattanzio, Rossano; Botti, Gerardo; Gatta, Valentina; D'Aurora, Marco; Simionati, Barbara; Piantelli, Mauro; Alberti, Saverio

    2016-08-18

    Traditional prognostic indicators of breast cancer, i.e. lymph node diffusion, tumor size, grading and estrogen receptor expression, are inadequate predictors of metastatic relapse. Thus, additional prognostic parameters appear urgently needed. Individual oncogenic determinants have largely failed in this endeavour. Only a few individual tumor growth drivers, e.g. mutated p53, Her-2, E-cadherin, Trops, did reach some prognostic/predictive power in clinical settings. As multiple factors are required to drive solid tumor progression, clusters of such determinants were expected to become stronger indicators of tumor aggressiveness and malignant progression than individual parameters. To identify such prognostic clusters, we went on to coordinately analyse molecular and histopathological determinants of tumor progression of post-menopausal breast cancers in the framework of a multi-institutional case series/case-control study. A multi-institutional series of 217 breast cancer cases was analyzed. Twenty six cases (12 %) showed disease relapse during follow-up. Relapsed cases were matched with a set of control patients by tumor diameter, pathological stage, tumor histotype, age, hormone receptors and grading. Histopathological and molecular determinants of tumor development and aggressiveness were then analyzed in relapsed versus non-relapsed cases. Stepwise analyses and model structure fitness assessments were carried out to identify clusters of molecular alterations with differential impact on metastatic relapse. p53, Bcl-2 and cathepsin D were shown to be coordinately associated with unique levels of relative risk for disease relapse. As many Ras downstream targets, among them matrix metalloproteases, are synergistically upregulated by mutated p53, whole-exon sequence analyses were performed for TP53, Ki-RAS and Ha-RAS, and findings were correlated with clinical phenotypes. Notably, TP53 insertion/deletion mutations were only detected in relapsed cases

  14. Synergistic effect of Bcl-2 and cyclin A2 on adverse recurrence-free survival in stage I non-small cell lung cancer.

    Science.gov (United States)

    Ko, Eunkyung; Kim, Yujin; Cho, Eun Yoon; Han, Jungho; Shim, Young Mog; Park, Joobae; Kim, Duk-Hwan

    2013-03-01

    The prognostic significance of cyclin A2 overexpression in non-small cell lung cancer (NSCLC) is controversial. To understand the effect of cyclin A2 on recurrence in NSCLC, we retrospectively analyzed the expression of Bcl-2, cyclin A2, E-cadherin, Ki-67, and p53 using immunohistochemistry in 635 NSCLCs. Overexpression of cyclin A2 was found in 466 (73%) of 635 NSCLCs, and recurrence occurred in 291 (46%) of 635 NSCLCs with a median follow-up of 5.4 years. The relationship between recurrence and cyclin A2 overexpression was not homogenous by pathologic stage (Breslow-Day test for homogeneity, P = 0.007). Overexpression of cyclin A2 was associated with poor recurrence-free survival (RFS) in 374 stage I NSCLCs (P = 0.02), and RFS was worse in patient with negative expression of Bcl-2 than those with positive expression of Bcl-2. Cox proportional hazard analysis showed that stage I NSCLC patients with overexpression of cyclin A2 and negative expression of Bcl-2 had poorer RFS (hazard ratio = 3.86, 95% confidence interval = 1.07-15.77; P = 0.03) than those with normal expression of cyclin A2 and Bcl-2, after adjusting for age, adjuvant radiotherapy, and histology. Neural network and generalized linear model including cyclin A2 and Bcl-2 showed best performance in the prediction of recurrence; error rates for neural network and generalized linear model were 15% and 12%, respectively. Negative effect of cyclin A2 on RFS in stage I NSCLC was aggravated by negative expression of Bcl-2.

  15. Lysosomal cathepsin initiates apoptosis, which is regulated by photodamage to Bcl-2 at mitochondria in photodynamic therapy using a novel photosensitizer, ATX-s10 (Na).

    Science.gov (United States)

    Ichinose, Shuji; Usuda, Jitsuo; Hirata, Takeshi; Inoue, Tatsuya; Ohtani, Keishi; Maehara, Sachio; Kubota, Mitsuhiro; Imai, Kentarou; Tsunoda, Yoshihiko; Kuroiwa, Yukari; Yamada, Kimito; Tsutsui, Hidemitsu; Furukawa, Kinya; Okunaka, Tetsuya; Oleinick, Nancy L; Kato, Harubumi

    2006-08-01

    ATX-s10 is a novel and second-generation photosensitizer for photodynamic therapy (PDT). In order to conduct clinical trials of ATX-s10-PDT and/or extend its clinical applications, it is very important to elucidate the mechanisms of the action of ATX-s10-PDT. We examined the apoptic response against ATX-s10-PDT using a Bcl-2 or Bcl-2 mutant overexpressing cells. Using fluorescent microscopy, ATX-s10 localized not only to mitochondria but also to lysosomes and possibly other intracellular organelles, but not to the plasma membrane or the nucleus. These results suggest that ATX-s10-PDT can damage mitochondria and lysosomes. By Western blot analysis, ATX-s10-PDT damaged Bcl-2, which localized preferentially at mitochondrial membranes, and caused Bcl-2 to cross-link immediately after laser irradiation. However, ATX-s10-PDT was not able to rapidly induce morphologically typical apoptosis (i.e. chromatin condensation and fragmentation) as PDT using mitochondria targeted photosensitizers, such as phthalocyanine 4 (Pc 4). Pharmacological inhibitions of lysosomal cytokine protease cathepsins, such as cathepsin B and D, protected MCF-7c3 cells (human breast cancer cells expressing stably transfected procaspase-3) from apoptosis caused by ATX-s10-PDT. Overexpression of wild-type Bcl-2 or Bcl-2Delta33-54 resulted in relative resistance of cells to ATX-s10-PDT, as assessed by the degree of morphological apoptosis or loss of clonogenicity. We conclude that lysosomal damage by ATX-s10-PDT can initiate apoptotic response and this apoptotic pathway can be regulated by photodamage to Bcl-2 via mitochondrial damage.

  16. Gene conversion is strongly induced in human cells by double-strand breaks and is modulated by the expression of BCL-XL

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    Wiese, Claudia; Pierce, Andrew J.; Gauny, Stacey S.; Jasin, Maria; Kronenberg, Amy

    2001-09-25

    Homology-directed repair (HDR) of DNA double-strand breaks (DSBs) is a well-established mechanism that contributes to the maintenance of genomic stability in rodent cells, and it has been assumed that HDR is of similar importance in the repair of DSBs in human cells. However, in addition to promoting genomic stability, some outcomes of homologous recombination can be deleterious, suggesting that factors exist to regulate HDR. We previously demonstrated that overexpression of BCL-2 or BCL-xL enhanced the frequency of x-ray-induced mutations involving the TK1 locus, including loss of heterozygosity (LOH) events presumed to arise by mitotic recombination. The present study was designed to test whether HDR is a prominent DSB repair pathway in human cells, and to directly determine whether ectopic expression of BCL-xL affects HDR. We used the B-lymphoblastoid cell line TK6, which expresses wild-type TP53 and resembles normal lymphocytes in undergoing apoptosis following! genotoxic stress. U sing isogenic derivatives of TK6 cells (TK6-neo, TK6-bcl-xL), we find that a DSB in an integrated HDR reporter stimulates gene conversion 40-50-fold in TK6-neo cells, demonstrating that a DSB can be efficiently repaired by gene conversion in human cells. Significantly, DSB-induced gene conversion events are 3- to 4-fold more frequent in BCL-xL overexpressing cells. The results demonstrate that HDR plays an important role in maintaining genomic integrity in human cells and that ectopic expression of BCL-xL enhances HDR of DSBs. To our knowledge, this is the first study to highlight a function for BCL-xL in modulating DSB repair in human cells.

  17. Prognostic Significance of Bcl-2 and p53 Protein Expressions and Ki67 Proliferative Index in Diffuse Large B-cell Lymphoma

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    Betül Bolat Küçükzeybek

    2013-09-01

    Full Text Available Objective: Diffuse large B-cell lymphoma (DLBCL is a high-grade neoplasm that has heterogeneous properties in clinical, morphological, and immunophenotypic aspects. In the present study the effects of p53, Bcl-2, and Ki67 on prognosis and their relationships with clinical parameters were examined. Materials and Methods: Thirty-five patients who had been diagnosed with nodally located DLBCL at İzmir Atatürk Training and Research Hospital between January 1999 and June 2006 were included in the study. The Ann Arbor classification system was used to determine the stage of the patients. The patients were evaluated according to age, sex, stage, B symptoms, extranodal involvement, and lactate dehydrogenase (LDH level as well as immunohistochemically. P53 protein and Bcl-2 oncoprotein expressions and Ki67 proliferation index were assessed immunohistochemically. Results: High Bcl-2 expression was found in 9 patients (25.7%, high p53 expression was found in 10 patients (28.6%, and high Ki67 was observed in 23 patients (65.7%. There was no significant correlation between p53 expression, Bcl-2 expression, or Ki67 proliferation index and age, sex, stage, B symptoms, extranodal involvement, LDH level, and overall survival (p>0.05. We did not find a relationship among p53 expression, Bcl-2 expression, Ki67 proliferation index, and prognosis (p>0.05. There was no significant relationship between overall survival and age, sex, stage, B symptoms, extranodal involvement, or LDH level (p>0.05. Our results revealed that Bcl-2 and p53 protein expressions and Ki67 proliferation index have no effect on overall survival of patients with DLBCL. Conclusion: The prognostic importance of p53 and Bcl-2 protein expressions and Ki67 proliferation index in DLBCL, which has biological and clinical heterogeneity, can be understood in a large series of studies that have subclasses and immunohistochemical markers with optimal cut-off values.

  18. Association between Virulence Factors and TRAF1/4-1BB/Bcl-xL Expression in Gastric Mucosa Infected with Helicobacter pylori

    Directory of Open Access Journals (Sweden)

    Fen Wang

    2015-01-01

    Full Text Available Objective. CagA+/vacAs1+/vacAm1+ Helicobacter pylori upregulates the expression of tumor necrosis factor receptor–associated factor 1 (TRAF1, tumor necrosis factor receptor superfamily member 9 (4-1BB, and B-cell lymphoma-extra large (Bcl-xL in human gastric epithelial cells. We investigated the correlation between cagA/vacAs1/vacAm1 and TRAF1/4-1BB/Bcl-xL expression in gastric mucosal tissue of patients with gastric disorders. Methods. We collected gastric mucosa samples from 35 chronic, nonatrophic gastritis (CG patients, 41 atrophic gastritis patients, 44 intestinal metaplasia with atypical hyperplasia (IM patients, and 28 gastric carcinoma (Ca patients. The expression of  TRAF1, 4-1BB, and Bcl-xL was determined using western blotting. The expression of cagA, vacAs1, and vacAm1 in H. pylori was examined with polymerase chain reaction. Results. The expression of TRAF1, 4-1BB, and Bcl-xL was significantly upregulated in IM and Ca patients (P<0.05 compared with CG. There were more cases of cagA+/vacAs1+/vacAm1+ H. pylori infection in samples with elevated TRAF1, 4-1BB, or Bcl-xL expression (P<0.05. Additionally, there were a remarkably large number of samples with upregulated TRAF1/4-1BB/Bcl-xL expression in cases of cagA+/vacAs1+/vacAm1+ H. pylori infection (44 cases, 67.7%; P<0.05. Conclusions. The pathogenesis of IM and Ca may be promoted by cagA+/vacAs1+/vacAm1+ H. pylori, possibly via upregulated TRAF1, 4-1BB, and Bcl-xL in gastric mucosal tissue.

  19. Involvement of Bcl-xL degradation and mitochondrial-mediated apoptotic pathway in pyrrolizidine alkaloids-induced apoptosis in hepatocytes

    International Nuclear Information System (INIS)

    Ji Lili; Chen Ying; Liu Tianyu; Wang Zhengtao

    2008-01-01

    Pyrrolizidine alkaloids (PAs) are natural hepatotoxins with worldwide distribution in more than 6000 high plants including medicinal herbs or teas. The aim of this study is to investigate the signal pathway involved in PAs-induced hepatotoxicity. Our results showed that clivorine, isolated from Ligularia hodgsonii Hook, decreased cell viability and induced apoptosis in L-02 cells and mouse hepatocytes. Western-blot results showed that clivorine induced caspase-3/-9 activation, mitochondrial release of cytochrome c and decreased anti-apoptotic Bcl-xL in a time (8-48 h)- and concentration (1-100 μM)-dependent manner. Furthermore, inhibitors of pan-caspase, caspase-3 and caspase-9 significantly inhibited clivorine-induced apoptosis and rescued clivorine-decreased cell viability. Polyubiquitination of Bcl-xL was detected after incubation with 100 μM clivorine for 40 h in the presence of proteasome specific inhibitor MG132, indicating possible degradation of Bcl-xL protein. Furthermore, pretreatment with MG132 or calpain inhibitor I for 2 h significantly enhanced clivorine-decreased Bcl-xL level and cell viability. All the other tested PAs such as senecionine, isoline and monocrotaline decreased mouse hepatocytes viability in a concentration-dependent manner. Clivorine (10 μM) induced caspase-3 activation and decreased Bcl-xL was also confirmed in mouse hepatocytes. Meanwhile, another PA senecionine isolated from Senecio vulgaris L also induced apoptosis, caspase-3 activation and decreased Bcl-xL in mouse hepatocytes. In conclusion, our results suggest that PAs may share the same hepatotoxic signal pathway, which involves degradation of Bcl-xL protein and thus leading to the activation of mitochondrial-mediated apoptotic pathway

  20. Increase in Bcl2 expression of penile and prostate cells of Sprague Dawley male rats following treatment with buceng (combination of Pimpinella alpina molk with Eurycoma longifolia Jack

    Directory of Open Access Journals (Sweden)

    Taufiqurrachman Nasihun

    2015-04-01

    Full Text Available Background: Treatment with buceng combination of Eurycoma longifolia Jack and Pimpinella alpine Molk has been proven to increase testosterone level, decrease apoptosis and caspase3 expression. Bcl2 is an antiapoptotic protein found in cytoplasm which inhibits cells apoptosis. This study was aimed to investigate the effect of buceng on Bcl2 expression on penile and prostate tissues of the rats. Methods: In this experimental study, 24 male Sprague Dawley rats of 90 days old, weighing ± 300 grams, were randomly assigned into four groups. Group A, normal rats. Group B, castrated rats and treated with buceng 100 mg/day, per oral (Cast-Bcg; Group C, castrated rats and treated with 2 ml of water as placebo against buceng (Cast-Plac. Group D, castrated rats, treated with mesterolone 6.75 mg/day, per oral, as exogenous testosterone (Cast-Mest. All rats were treated for 30 days. Manova test was used to analyze the different expression of Bcl2 among groups with significance level at p ≤ 0.05. Results: Castration was associated with significant decrease of Bcl2 expression in the penile and prostate tissues (53.0 and 50.9%, respectively compared to normal rats (82.6 and 84.2%, respectively, p < 0.001. Treatment with mesterolone reversed Bcl2 expression (77.1 and 78.1% to a near normal level. The same level of Bcl2 expression was also observed with buceng treatment (73.8 and 78.2%.Conclusion: The treatment with buceng could enhance Bcl2 expression in penile and prostate tissues, comparable to normal rats and mesterolone treated rats.

  1. The apoptotic members CD95, BclxL, and Bcl-2 cooperate to promote cell migration by inducing Ca2+ flux from the endoplasmic reticulum to mitochondria

    Science.gov (United States)

    Fouqué, A; Lepvrier, E; Debure, L; Gouriou, Y; Malleter, M; Delcroix, V; Ovize, M; Ducret, T; Li, C; Hammadi, M; Vacher, P; Legembre, P

    2016-01-01

    Metalloprotease-processed CD95L (cl-CD95L) is a soluble cytokine that implements a PI3K/Ca2+ signaling pathway in triple-negative breast cancer (TNBC) cells. Accordingly, high levels of cl-CD95L in TNBC women correlate with poor prognosis, and administration of this ligand in an orthotopic xenograft mouse model accelerates the metastatic dissemination of TNBC cells. The molecular mechanism underlying CD95-mediated cell migration remains unknown. Here, we present genetic and pharmacologic evidence that the anti-apoptotic molecules BclxL and Bcl-2 and the pro-apoptotic factors BAD and BID cooperate to promote migration of TNBC cells stimulated with cl-CD95L. BclxL was distributed in both endoplasmic reticulum (ER) and mitochondrion membranes. The mitochondrion-localized isoform promoted cell migration by interacting with voltage-dependent anion channel 1 to orchestrate Ca2+ transfer from the ER to mitochondria in a BH3-dependent manner. Mitochondrial Ca2+ uniporter contributed to this flux, which favored ATP production and cell migration. In conclusion, this study reveals a novel molecular mechanism controlled by BclxL to promote cancer cell migration and supports the use of BH3 mimetics as therapeutic options not only to kill tumor cells but also to prevent metastatic dissemination in TNBCs. PMID:27367565

  2. Oligo-Porphyran Ameliorates Neurobehavioral Deficits in Parkinsonian Mice by Regulating the PI3K/Akt/Bcl-2 Pathway

    Directory of Open Access Journals (Sweden)

    Yingjuan Liu

    2018-03-01

    Full Text Available Parkinson’s disease (PD is a neurodegenerative movement disorder that is caused by a selective loss of dopaminergic neurons. Current PD treatments provide symptomatic relief but do not prevent or decelerate disease progression. Previous studies have suggested that acetylated and phosphorylated porphyran, derived from Porphyra, produces a neuroprotective effect against 6-OHDA-induced damage. Due to its antioxidant and neuroprotective potential, this study evaluates whether oligo-porphyran (OP could be beneficial in an experimental model of PD in mice. The drug 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP was intraperitoneally injected (20 mg/kg body weight for seven days to simulate PD, followed by OP administration. We found that the behavioral deficits in spontaneous motor activity, latency to descend in a pole test, and suspension in a traction test were ameliorated, and excessive dopamine (DA metabolism was suppressed after OP treatment. Additionally, we found that OP protected dopaminergic neurons by preventing MPTP-induced decreases in dopaminergic transporter and tyrosine hydroxylase protein levels. We speculated whether OP regulates a signaling pathway that affects the behavioral changes seen in PD mice. In this study, the PI3K/Akt/Bcl-2 pathway was detected. Our results demonstrate that OP increased the phosphorylation of PI3K/Akt/GSK-3β and inhibited the activation of caspase-3 and poly (ADP-ribose polymerase, with changes in the Bax/Bcl-2 ratio. These results showed that OP might promote DA neuron survival in vivo by regulating the PI3K/Akt/Bcl-2 pathway, thereby ameliorating the neurobehavioral deficits in a PD mouse model and suggesting OP as a neuroprotective treatment for PD.

  3. Lactate promotes resistance to glucose starvation via upregulation of Bcl-2 mediated by mTOR activation.

    Science.gov (United States)

    Huang, Chen; Sheng, Shile; Li, Rui; Sun, Xiaoguang; Liu, Jianju; Huang, Gang

    2015-02-01

    Solid tumors grow faster and need more glucose than normal tissue; however, due to poor angiogenesis and excessive growth, tumors remote from blood vessels are always under glucose starvation. Even so, cancer cells remain alive in vivo. Thus, making cancer cells sensitive to glucose depletion may potentially provide an effective strategy for cancer intervention. Tumors that obtain sufficient glucose generate a large amount of lactate. Therefore, we proposed that lactate, a tumor microenvironment factor, may allow cancer cells to develop resistance to glucose starvation-induced death. We cultured cancer cells in no-glucose medium and added lactate to the medium. During the experiment, lactate helped cancer cells to escape from glucose starvation-induced cell death, without using lactate as an energy substrate, resulting in activation of Akt through PI3K. Akt activation plays a central role in cell growth through the activation of mammalian target of rapamycin (mTOR). Alteration of the PI3K/Akt/mTOR signaling pathway by inhibiting apoptosis induced specific upregulation of B-cell lymphoma 2 (Bcl-2) through translational control. In conclusion, this study showed that lactate rescues cancer cells from glucose starvation-induced cell death through regulation of the PI3K/Akt/mTOR/Bcl-2 signaling pathway. These data suggest that lactate is an important determinant of the sensitivity of tumors to glucose starvation, and reducing lactate or inhibiting the PI3K/Akt/mTOR/Bcl-2 signaling pathway may influence the response of cancers to glucose starvation.

  4. Ion energy distribution functions in inductively coupled radio-frequency discharges emdash Mixtures of Cl2/BCl3/Ar

    International Nuclear Information System (INIS)

    Nichols, C.A.; Woodworth, J.R.; Hamilton, T.W.

    1998-01-01

    We have used a gridded energy analyzer to measure positive ion energy distributions and fluxes at the grounded electrode of a high-density rf discharge. We present details of ion energies and fluxes in discharges containing mixtures of chlorine, boron trichloride and argon. These feedstock mixtures have been used extensively in the patterning of metal films for semiconductor interconnects. Our experiments were carried out in a Gaseous Electronics Conference Reference Cell which had been modified to produce inductively coupled discharges. The 15-cm-diam bottom electrode was grounded for these experiments. Stainless steel, anodized aluminum, and silicon were used as bottom electrode materials to understand the effects of various chamber boundary conditions on the ion energy parameters. In most cases, the ion energy distributions had a single peak, well separated from zero energy with a 1.0 endash 3.0 eV full width at half maximum. These peaks were typically centered at 12 endash 16 eV, with ion energy increasing as pressure decreased. Addition of BCl 3 to a Cl 2 discharge resulted in a reduction of total ion flux of more than a factor of 2, e.g., from 5 to 2.5 mA/cm 2 (20 mTorr, 200 W). The ion fluxes decreased with increasing pressures in BCl 3 /Cl 2 mixtures, while increasing with pressure in pure Cl 2 discharges. Addition of Ar to several mixtures of BCl 3 /Cl 2 changed the ion fluxes and mean ion energies by less than 15%. At high pressures or low inductive rf powers, the distributions can split into two overlapping peaks separated by as much as 8 eV. This splitting is indicative of capacitive coupling between the rf coil and the discharge. Insertion of a Faraday shield between the coil and the discharge removed most of the splitting. copyright 1998 American Vacuum Society. thinsp

  5. Electromagnetic radiation at 900 MHz induces sperm apoptosis through bcl-2, bax and caspase-3 signaling pathways in rats.

    Science.gov (United States)

    Liu, Qi; Si, Tianlei; Xu, Xiaoyun; Liang, Fuqiang; Wang, Lufeng; Pan, Siyi

    2015-08-04

    The decreased reproductive capacity of men is an important factor contributing to infertility. Accumulating evidence has shown that Electromagnetic radiation potentially has negative effects on human health. However, whether radio frequency electromagnetic radiation (RF-EMR) affects the human reproductive system still requires further investigation. Therefore, The present study investigates whether RF-EMR at a frequency of 900 MHz can trigger sperm cell apoptosis and affect semen morphology, concentration, and microstructure. Twenty four rats were exposed to 900 MHz electromagnetic radiation with a special absorption rate of 0.66 ± 0.01 W/kg for 2 h/d. After 50d, the sperm count, morphology, apoptosis, reactive oxygen species (ROS), and total antioxidant capacity (TAC), representing the sum of enzymatic and nonenzymatic antioxidants, were investigated. Western blotting and reverse transcriptase PCR were used to determine the expression levels of apoptosis-related proteins and genes, including bcl-2, bax, cytochrome c, and capase-3. In the present study, the percentage of apoptotic sperm cells in the exposure group was significantly increased by 91.42% compared with the control group. Moreover, the ROS concentration in exposure group was increased by 46.21%, while the TAC was decreased by 28.01%. Radiation also dramatically decreased the protein and mRNA expression of bcl-2 and increased that of bax, cytochrome c, and capase-3. RF-EMR increases the ROS level and decreases TAC in rat sperm. Excessive oxidative stress alters the expression levels of apoptosis-related genes and triggers sperm apoptosis through bcl-2, bax, cytochrome c and caspase-3 signaling pathways.

  6. Immunohistochemical study of ki-67 and bcl-2 expression in some odontogenic cystic lesions with different clinical behaviors

    Directory of Open Access Journals (Sweden)

    Seyed Hossein Tabatabaei

    2016-11-01

    Full Text Available Background: Cystic lesions with odontogenic epithelial origin and similar clinicoradiographic appearance, show different clinical behaviors. Objective: To compare some factors related to cell proliferation and escape from apoptosis in epithelium covering two groups of odontogenic cystic lesions with different clinical behaviors. Methods: In this cross-sectional study 11 paraffin-embedded samples were selected of each lesions radicular cyst, dentigerous cyst, odontogenic keratocyst, and unicystic ameloblastoma. The sample underwent immunohistochemical staining for investigating the expression of ki-67 antigen and bcl-2 protein. Data analyzed with SPSS17 software and Kruskal–Wallis and chi-square statistical tests. Findings: Most of ki-67 positive cells were observed in parabasal layer of odontogenic keratocyst [35.50±26.29%; P=0.001]. The average of ki-67-LI was more in parabasal layer of aggressive group (26.80±37.79% compared to non-aggressive group (4.04±3.38%, was not being statistically significant. The highest average of bcl-2-LI was 95±6.70% in basal layer of odontogenic keratocyst (P=0.001. In all layers, the average of bcl-2-LI was more in aggressive lesions compared to non-aggressive ones and the highest amount was found in basal layer (72.45±3.94×10% which was statistically significant (P=0.001. Conclusion: According to the results of this study, more expression of the markers related to escape from apoptosis in aggressive lesions group compared to non-aggressive group, suggests that escape from apoptosis had a more critical role in aggressive behavior of odontogenic cystic lesions.

  7. Bcl-2-like Protein 11 (BIM) Expression Is Associated with Favorable Prognosis for Patients with Cervical Cancer.

    Science.gov (United States)

    Kim, Bo Wook; Cho, Hanbyoul; Ylaya, Kris; Kitano, Haruhisa; Chung, Joon-Yong; Hewitt, Stephen M; Kim, Jae-Hoon

    2017-09-01

    Bcl-2-like protein 11 (BIM) is a pro-apoptotic member of the Bcl-2 protein family. BIM elicits cell death by binding to pro-survival Bcl-2 proteins. Even though the association of BIM expression with cell death has been investigated, its clinical survival significance in cervical cancer has not. In the current study, the prognostic significance of BIM in cervical cancer was investigated. The study included normal cervical tissues (n=254), cervical intraepithelial neoplasia (CIN) tissues (n=275), and invasive cervical cancer (n=164). In order to identify BIM expression, immunohistochemistry (IHC) was performed, and IHC scoring by quantitative digital image analysis was determined. Then, the association of BIM with prognostic factors was investigated. BIM expression was higher in cervical cancer than normal cervical tissues (pBIM expression than did poor differentiation (p=0.001). Also, BIM expression was high in radiation-sensitive cervical cancer relative to radiation-resistant cancer (p=0.049). High BIM expression showed better 5-year disease-free survival (DFS) and overall survival (OS) rates (p=0.049 and π=0.030, respectively) than did low expression. In a multivariate analysis, BIM was shown to be an independent risk factor for DFS and OS in cervical cancer, with hazard ratios of 0.22 (p=0.006) and 0.46 (p=0.046), respectively. BIM is associated with favorable prognostic markers for prediction of DFS and OS in cervical cancer. High BIM expression is a potential prognostic marker as well as a chemotherapeutic target for cervical cancer. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

  8. Characterization of Spontaneous Immune Responses against Long Peptides Derived from Bcl-X(L) in Cancer Patients Using Elispot

    DEFF Research Database (Denmark)

    Svane, Inge Marie; Straten, Per thor; Andersen, Mads Hald

    2012-01-01

    In recent years we and others have used the ELISPOT assay successfully to identify novel tumor antigens by the characterization of spontaneous HLA class I restricted immune responses against a number of minimal 9–10 amino acid long peptide epitopes. In the present study, we examined the capability....... In conclusion several long BCL-X(L) derived peptide epitopes exist, which may be used in anti-cancer immunity. Furthermore, the ELISPOT assay offers an attractive and sensitive method for the characterization of spontaneous immune reactivity against long peptides....

  9. Persea declinata (Bl. Kosterm Bark Crude Extract Induces Apoptosis in MCF-7 Cells via G0/G1 Cell Cycle Arrest, Bcl-2/Bax/Bcl-xl Signaling Pathways, and ROS Generation

    Directory of Open Access Journals (Sweden)

    Putri Narrima

    2014-01-01

    Full Text Available Persea declinata (Bl. Kosterm is a member of the Lauraceae family, widely distributed in Southeast Asia. It is from the same genus with avocado (Persea americana Mill, which is widely consumed as food and for medicinal purposes. In the present study, we examined the anticancer properties of Persea declinata (Bl. Kosterm bark methanolic crude extract (PDM. PDM exhibited a potent antiproliferative effect in MCF-7 human breast cancer cells, with an IC50 value of 16.68 µg/mL after 48 h of treatment. We observed that PDM caused cell cycle arrest and subsequent apoptosis in MCF-7 cells, as exhibited by increased population at G0/G1 phase, higher lactate dehydrogenase (LDH release, and DNA fragmentation. Mechanistic studies showed that PDM caused significant elevation in ROS production, leading to perturbation of mitochondrial membrane potential, cell permeability, and activation of caspases-3/7. On the other hand, real-time PCR and Western blot analysis showed that PDM treatment increased the expression of the proapoptotic molecule, Bax, but decreased the expression of prosurvival proteins, Bcl-2 and Bcl-xL, in a dose-dependent manner. These findings imply that PDM could inhibit proliferation in MCF-7 cells via cell cycle arrest and apoptosis induction, indicating its potential as a therapeutic agent worthy of further development.

  10. Study on the apoptosis and Bcl-2/Bax expression of human hepatoma SMMC-7721 cells after exposure to heavy-ion and X-ray irradiations

    International Nuclear Information System (INIS)

    Ye Lanping; Xu Hua; An Lizhe; Jin Xiaodong; Li Qiang

    2007-01-01

    This study is aimed at observing the apoptosis and Bcl-2/Bax gene expression of mammalian cells following heavy-ion and X-ray irradiations. Exponentially growing human hepatoma SMMC-7721 cells cultured in vitro were irradiated with a 12 C ion beam of 50 MeV/u (corresponding to a LET value of 44.56 keV/S38m) from Heavy Ion Research Facility in Lanzhou (HIRFL) at doses varying from 0 to 3 Gy. The X-ray irradiation (8 MV) was performed in the therapy unit of the General Hospital of the Lanzhou Military Area. Survival fractions of irradiated cells at various doses were measured by means of MTT assay. Apoptotic cells after irradiation were analyzed with fluorescence microscope and flow cytometer (FCM). Immuno-histological assay were applied to detect the expression of Bcl-2/Bax genes in the irradiated cells. The survival fraction of SMMC-7721 cells decreased gradually (vs. control p<0.05) with increasing the dose of the carbon ion beam more obviously than X-ray irradiation, and the carbon ion irradiation efficiently induced cell apoptosis and significantly promoted the expression of Bax gene while Bcl-2 gene expression was restrained. High-LET heavy ion beam would induce cell apoptosis effectively than low-LET X-ray, and the apoptosis rate is correlated with the transcription of Bcl-2/Bax and the ratio of Bcl-2/Bax in human hepatoma SMMC-7721 cells after irradiation to heavy ion beam. (author)

  11. Targeting BCL2 Family in Human Myeloid Dendritic Cells: A Challenge to Cure Diseases with Chronic Inflammations Associated with Bone Loss

    Directory of Open Access Journals (Sweden)

    Selma Olsson Åkefeldt

    2013-01-01

    Full Text Available Rheumatoid arthritis (RA and Langerhans cell histiocytosis (LCH are common and rare diseases, respectively. They associate myeloid cell recruitment and survival in inflammatory conditions with tissue destruction and bone resorption. Manipulating dendritic cell (DC, and, especially, regulating their half-life and fusion, is a challenge. Indeed, these myeloid cells display pathogenic roles in both diseases and may be an important source of precursors for differentiation of osteoclasts, the bone-resorbing multinucleated giant cells. We have recently documented that the proinflammatory cytokine IL-17A regulates long-term survival of DC by inducing BCL2A1 expression, in addition to the constitutive MCL1 expression. We summarize bibliography of the BCL2 family members and their therapeutic targeting, with a special emphasis on MCL1 and BCL2A1, discussing their potential impact on RA and LCH. Our recent knowledge in the survival pathway, which is activated to perform DC fusion in the presence of IL-17A, suggests that targeting MCL1 and BCL2A1 in infiltrating DC may affect the clinical outcomes in RA and LCH. The development of new therapies, interfering with MCL1 and BCL2A1 expression, to target long-term surviving inflammatory DC should be translated into preclinical studies with the aim to increase the well-being of patients with RA and LCH.

  12. Discovery of a novel B-cell lymphoma 6 (BCL6)-corepressor interaction inhibitor by utilizing structure-based drug design.

    Science.gov (United States)

    Yasui, Takeshi; Yamamoto, Takeshi; Sakai, Nozomu; Asano, Kouhei; Takai, Takafumi; Yoshitomi, Yayoi; Davis, Melinda; Takagi, Terufumi; Sakamoto, Kotaro; Sogabe, Satoshi; Kamada, Yusuke; Lane, Weston; Snell, Gyorgy; Iwata, Masashi; Goto, Masayuki; Inooka, Hiroshi; Sakamoto, Jun-Ichi; Nakada, Yoshihisa; Imaeda, Yasuhiro

    2017-09-01

    B-cell lymphoma 6 (BCL6) is a transcriptional repressor that can form complexes with corepressors via protein-protein interactions (PPIs). The complexes of BCL6 and corepressors play an important role in the formation of germinal centers (GCs), and differentiation and proliferation of lymphocytes. Therefore, BCL6-corepressor interaction inhibitors would be drug candidates for managing autoimmune diseases and cancer. Starting from high-throughput screening hits 1a and 2a, we identified a novel BCL6-corepressor interaction inhibitor 8c (cell-free enzyme-linked immunosorbent assay [ELISA] IC 50 =0.10µM, cell-based mammalian two-hybrid [M2H] assay IC 50 =0.72µM) by utilizing structure-based drug design (SBDD) based on an X-ray crystal structure of 1a bound to BCL6. Compound 8c also showed a good pharmacokinetic profile, which was acceptable for both in vitro and in vivo studies. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Expression of beclin 1 in primary salivary adenoid cystic carcinoma and its relation to Bcl-2 and p53 and prognosis

    International Nuclear Information System (INIS)

    Jiang, L.C.; Huang, S.Y.; Zhang, D.S.; Zhang, S.H.; Li, W.G.; Zheng, P.H.; Chen, Z.W.

    2014-01-01

    Beclin 1 plays a critical role in autophagy and functions as a haploinsufficient tumor suppressor. The expression and prognostic significance of beclin 1 in head and neck adenoid cystic carcinoma (ACC) are largely unexplored. Therefore, we investigated the expression of beclin 1, Bcl-2, and p53 in head and neck ACC tissue. Tissue samples from 35 cases (15 females, 20 males) of head and neck ACC were utilized for immunohistochemistry. Beclin 1 expression was observed in 32 cases (91.4%) and considered to be high in 15 cases (42.9%) and low in 20 cases (57.1%). Beclin 1 expression was significantly correlated with a histological growth pattern (P=0.046) and histological grade (P=0.037). Beclin 1 expression was inversely correlated with Bcl-2 expression (P=0.013) and significantly associated with overall survival (P=0.006). Bcl-2 and p53 expression were observed in 21 cases (60.0%) and 16 cases (45.7%). Bcl-2 expression was significantly correlated with perineural invasion (P=0.041) and not associated with overall survival (P=0.053). p53 expression was directly correlated with beclin 1 expression (P=0.044). Our results indicated that beclin 1 may be a novel, promising prognostic factor for clinical outcome in head and neck ACC patients and may play a part in the development of head and neck ACC by interacting with Bcl-2 and p53

  14. Expression of beclin 1 in primary salivary adenoid cystic carcinoma and its relation to Bcl-2 and p53 and prognosis

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, L.C.; Huang, S.Y.; Zhang, D.S.; Zhang, S.H.; Li, W.G.; Zheng, P.H.; Chen, Z.W. [Shandong Provincial Hospital Affiliated to Shandong University, Department of Oral and Maxillofacial Surgery, Jinan, China, Department of Oral and Maxillofacial Surgery, Shandong Provincial Hospital Affiliated to Shandong University, Jinan (China)

    2014-03-03

    Beclin 1 plays a critical role in autophagy and functions as a haploinsufficient tumor suppressor. The expression and prognostic significance of beclin 1 in head and neck adenoid cystic carcinoma (ACC) are largely unexplored. Therefore, we investigated the expression of beclin 1, Bcl-2, and p53 in head and neck ACC tissue. Tissue samples from 35 cases (15 females, 20 males) of head and neck ACC were utilized for immunohistochemistry. Beclin 1 expression was observed in 32 cases (91.4%) and considered to be high in 15 cases (42.9%) and low in 20 cases (57.1%). Beclin 1 expression was significantly correlated with a histological growth pattern (P=0.046) and histological grade (P=0.037). Beclin 1 expression was inversely correlated with Bcl-2 expression (P=0.013) and significantly associated with overall survival (P=0.006). Bcl-2 and p53 expression were observed in 21 cases (60.0%) and 16 cases (45.7%). Bcl-2 expression was significantly correlated with perineural invasion (P=0.041) and not associated with overall survival (P=0.053). p53 expression was directly correlated with beclin 1 expression (P=0.044). Our results indicated that beclin 1 may be a novel, promising prognostic factor for clinical outcome in head and neck ACC patients and may play a part in the development of head and neck ACC by interacting with Bcl-2 and p53.

  15. The role of BCL11A and HMIP-2 polymorphisms on endogenous and hydroxyurea induced levels of fetal hemoglobin in sickle cell anemia patients from southern Brazil.

    Science.gov (United States)

    Friedrisch, João Ricardo; Sheehan, Vivien; Flanagan, Jonathan M; Baldan, Alessandro; Summarell, Carly C Ginter; Bittar, Christina Matzembacher; Friedrisch, Bruno Kras; Wilke, Ianaê Indiara; Ribeiro, Camila Blos; Daudt, Liane Esteves; da Rocha Silla, Lucia Mariano

    2016-11-01

    High levels of fetal hemoglobin (HbF) reduce sickle cell anemia (SCA) morbidity and mortality. HbF levels vary considerably and there is a strong genetic component that influences HbF production. Genetic polymorphisms at three quantitative trait loci (QTL): Xmn1-HBG2, HMIP-2 and BCL11A, have been shown to influence HbF levels and disease severity in SCA. Hydroxyurea (HU) is a drug that increases HbF. We investigated the influence of single nucleotide polymorphisms (SNPs) at the Xmn1-HBG2 (rs7482144); BCL11A (rs1427407, rs4671393 and rs11886868); and HMIP-2 (rs9399137 and rs9402686) loci on baseline and HU-induced HbF levels in 111 HbSS patients. We found that both BCL11A and HMIP-2 were associated with increased endogenous levels of HbF. Interestingly, we also found that BCL11A was associated with higher induction of HbF with HU. This effect was independent of the effect of BCL11A on baseline HbF levels. Additional studies will be needed to validate these findings and explain the ample inter-individual variations in HbF levels at baseline and HU-induced in patients with SCA. Copyright © 2016 Elsevier Inc. All rights reserved.

  16. Bcl-2 Decreases the Affinity of SQSTM1/p62 to Poly-Ubiquitin Chains and Suppresses the Aggregation of Misfolded Protein in Neurodegenerative Disease.

    Science.gov (United States)

    Zhou, Liang; Wang, Hongfeng; Ren, Haigang; Hu, Qingsong; Ying, Zheng; Wang, Guanghui

    2015-12-01

    Poly-ubiquitinated protein aggregate formation is the most striking hallmark of various neurodegenerative diseases such as Alzheimer's disease, Huntington's disease, amyotrophic lateral sclerosis, and prion disease. Mutations of many ubiquitin-associated proteins involved in the regulation of protein aggregation, such as SQSTM1/p62 (p62), parkin, and VCP, are closely linked to neurodegeneration. B-cell lymphoma 2 (Bcl-2) is a key regulator in autophagy, apoptosis, and mitochondria quality control in many cell types including neurons, and it plays important roles in the pathogenesis of neurodegenerative diseases mentioned above. Our previous work showed that Bcl-2 can directly bind to p62, and here we report that Bcl-2 directly interacts with the N-terminus of p62, but not the C-terminus (UBA domain). Interestingly and importantly, Bcl-2 affects the affinity of p62 to poly-ubiquitin chains and suppresses the aggregation of poly-ubiquitinated proteins such as mutant huntingtin associated with Huntington's disease. Our study reveals a role of Bcl-2 that involves in the regulation of misfolded proteins.

  17. Differential nigral expression of Bcl-2 protein family in chronically haloperidol and clozapine-treated rats: role in neurotoxicity and stereotyped behavior.

    Science.gov (United States)

    Saldaña, M; Bonastre, M; Aguilar, E; Marin, C

    2007-02-01

    Tardive dyskinesia (TD) is a syndrome characterized by repetitive involuntary movements induced by the administration of typical neuroleptics such as haloperidol. TD generally persists after haloperidol withdrawal indicating that haloperidol produces long-lasting changes in brain function. In contrast to the typicals, atypical medications, such as clozapine, have very low rates of TD. The mechanisms underlying drug-induced TD are poorly understood. We have investigated the role of nigral expression of the bcl-2 family of proteins on haloperidol-induced neurotoxicity. Rats were treated for 21 days with the following drugs: haloperidol (1 mg/kg), clozapine (1 mg/kg) or saline. After a 3-day washout period, apomorphine-induced stereotyped behavior was scored. Western blotting was performed to evaluate the nigral expression of the dopamine transporter (DAT), bax, bcl-x(L) and bcl-2 proteins. Haloperidol administration, but not clozapine, increased stereotyped behavior (pclozapine treatment significantly decreased the nigral expression of bax (pclozapine did not significantly modify the nigral expression of bcl-2. Our results suggest that the increase in bcl-2 expression in the haloperidol-treated animals might be a compensatory mechanism that may reflect cellular damage induced by haloperidol in the dopaminergic neurons in the pars compacta of the substantia nigra.

  18. Comparison of E-cadherin with STAT3 and apoptosis regulators: Bak and Bcl-xL in endometrioid adenocarcinomas of different ER-alpha immunoprofile.

    Science.gov (United States)

    Sulkowska, Urszula; Wincewicz, Andrzej; Kanczuga-Koda, Luiza; Koda, Mariusz; Sulkowski, Stanislaw

    2018-02-01

    E-cadherin is a factor of good prognosis in endometrioid adenocarcinomas, while STAT3 is an oncogenic driver of carcinogenesis. E-cadherin, Bak, Bcl-xL and STAT3 were immunohistochemically detected in 78 human endometrioid adenocarcinomas. E-cadherin correlated with STAT3 (p E-cadherin associated with Bak (p = .021, r = 0.319), Bcl-xL (p = .026, r = 0.309) and STAT3 (p E-cadherin correlated with Bak and Bcl-xL in both G1- and estrogen receptor (ER)-negative tumors with significant relation of E-cadherin and STAT3 in G1- and ER-negative tumors. Antigrowth synergy of expression was preserved for antiapoptotic Bak and proliferation-suppressing E-cadherin in IA adenocarcinomas (p = .031, r = 0.342) with no significance between Bak and E-cadherin or STAT3 and emerging correlation between E-cadherin and Bcl-xL in IB + II tumors instead (p = .003, r = 0.472). E-cadherin correlated with Bak and Bcl-xL in ER-positive adenocarcinomas (p =  .002, r = 0.382 and p E-cadherin and Bak) presumably due to progressing impairment of growth-inhibitory properties of clone of neoplastic cells within higher staging and poorer differentiation.

  19. MYC/BCL2 Co-Expression Is a Stronger Prognostic Factor Compared With the Cell-of-Origin Classification in Primary CNS DLBCL.

    Science.gov (United States)

    Shi, Qian-Yun; Feng, Xiao; Bao, Wei; Ma, Jie; Lv, Jing-Huan; Wang, Xuan; Rao, Qiu; Shi, Qun-Li

    2017-11-01

    Primary central nervous system (CNS) diffuse large B-cell lymphoma (DLBCL) is a subtype of DLBCL with an unfavorable prognosis and a poor response to the treatment. As we know, DLBCL is stratified into germinal center B-cell (GCB)-like and activated B-cell (ABC)-like subtypes with different prognosis according to their gene-expression characteristics. In this study, we analyzed a case series of 77 patients with primary CNS DLBCL. A difference in prognosis of GCB-like and ABC-like subtypes was noticed, but no statistical significance was found. However, significant prognostic value of MYC/BCL2 co-expression was shown. The cases with MYC/BCL2 co-expression did not show any predominance of the 2 subtypes in our cases. Furthermore, patients with MYC/BCL2 co-expression had significantly worse overall survival for both cell of origin (COO) subtypes. We conjecture that MYC/BCL2 co-expression is associated with a poorer prognosis and is independent of COO classification. Moreover, the data suggest that MYC/BCL2 co-expression is superior to COO classification assessed by immunohistochemical analysis in patients with primary CNS DLBCL. © 2017 American Association of Neuropathologists, Inc. All rights reserved.

  20. Differential protection by wildtype vs. organelle-specific Bcl-2 suggests a combined requirement of both the ER and mitochondria in ceramide-mediated caspase-independent programmed cell death

    Directory of Open Access Journals (Sweden)

    Belka Claus

    2009-10-01

    Full Text Available Abstract Background Programmed cell death (PCD is essential for development and homeostasis of multicellular organisms and can occur by caspase-dependent apoptosis or alternatively, by caspase-independent PCD (ciPCD. Bcl-2, a central regulator of apoptosis, localizes to both mitochondria and the endoplasmic reticulum (ER. Whereas a function of mitochondrial and ER-specific Bcl-2 in apoptosis has been established in multiple studies, corresponding data for ciPCD do not exist. Methods We utilized Bcl-2 constructs specifically localizing to mitochondria (Bcl-2 ActA, the ER (Bcl-2 cb5, both (Bcl-2 WT or the cytosol/nucleus (Bcl-2 ΔTM and determined their protective effect on ceramide-mediated ciPCD in transiently and stably transfected Jurkat cells. Expression of the constructs was verified by immunoblots. Ceramide-mediated ciPCD was induced by treatment with human recombinant tumor necrosis factor and determined by flow cytometric measurement of propidium iodide uptake as well as by optical analysis of cell morphology. Results Only wildtype Bcl-2 had the ability to efficiently protect from ceramide-mediated ciPCD, whereas expression of Bcl-2 solely at mitochondria, the ER, or the cytosol/nucleus did not prevent ceramide-mediated ciPCD. Conclusion Our data suggest a combined requirement for both mitochondria and the ER in the induction and the signaling pathways of ciPCD mediated by ceramide.

  1. Differential protection by wildtype vs. organelle-specific Bcl-2 suggests a combined requirement of both the ER and mitochondria in ceramide-mediated caspase-independent programmed cell death

    International Nuclear Information System (INIS)

    Deerberg, Andrea; Sosna, Justyna; Thon, Lutz; Belka, Claus; Adam, Dieter

    2009-01-01

    Programmed cell death (PCD) is essential for development and homeostasis of multicellular organisms and can occur by caspase-dependent apoptosis or alternatively, by caspase-independent PCD (ciPCD). Bcl-2, a central regulator of apoptosis, localizes to both mitochondria and the endoplasmic reticulum (ER). Whereas a function of mitochondrial and ER-specific Bcl-2 in apoptosis has been established in multiple studies, corresponding data for ciPCD do not exist. We utilized Bcl-2 constructs specifically localizing to mitochondria (Bcl-2 ActA), the ER (Bcl-2 cb5), both (Bcl-2 WT) or the cytosol/nucleus (Bcl-2 ΔTM) and determined their protective effect on ceramide-mediated ciPCD in transiently and stably transfected Jurkat cells. Expression of the constructs was verified by immunoblots. Ceramide-mediated ciPCD was induced by treatment with human recombinant tumor necrosis factor and determined by flow cytometric measurement of propidium iodide uptake as well as by optical analysis of cell morphology. Only wildtype Bcl-2 had the ability to efficiently protect from ceramide-mediated ciPCD, whereas expression of Bcl-2 solely at mitochondria, the ER, or the cytosol/nucleus did not prevent ceramide-mediated ciPCD. Our data suggest a combined requirement for both mitochondria and the ER in the induction and the signaling pathways of ciPCD mediated by ceramide

  2. bcl::Cluster : A method for clustering biological molecules coupled with visualization in the Pymol Molecular Graphics System.

    Science.gov (United States)

    Alexander, Nathan; Woetzel, Nils; Meiler, Jens

    2011-02-01

    Clustering algorithms are used as data analysis tools in a wide variety of applications in Biology. Clustering has become especially important in protein structure prediction and virtual high throughput screening methods. In protein structure prediction, clustering is used to structure the conformational space of thousands of protein models. In virtual high throughput screening, databases with millions of drug-like molecules are organized by structural similarity, e.g. common scaffolds. The tree-like dendrogram structure obtained from hierarchical clustering can provide a qualitative overview of the results, which is important for focusing detailed analysis. However, in practice it is difficult to relate specific components of the dendrogram directly back to the objects of which it is comprised and to display all desired information within the two dimensions of the dendrogram. The current work presents a hierarchical agglomerative clustering method termed bcl::Cluster. bcl::Cluster utilizes the Pymol Molecular Graphics System to graphically depict dendrograms in three dimensions. This allows simultaneous display of relevant biological molecules as well as additional information about the clusters and the members comprising them.

  3. Multimodal Interaction with BCL-2 Family Proteins Underlies the Pro-Apoptotic Activity of PUMA BH3

    Science.gov (United States)

    Edwards, Amanda L.; Gavathiotis, Evripidis; LaBelle, James L.; Braun, Craig R.; Opoku-Nsiah, Kwadwo A.; Bird, Gregory H.; Walensky, Loren D.

    2013-01-01

    SUMMARY PUMA is a pro-apoptotic BCL-2 family member that drives the apoptotic response to a diversity of p53-dependent and independent cellular insults. Deciphering the spectrum of PUMA interactions that confer its context-dependent pro-apoptotic properties remains a high priority goal. Here, we report the synthesis of PUMA SAHBs, structurally-stabilized PUMA BH3 helices that, in addition to broadly targeting anti-apoptotic proteins, directly bind to BAX. NMR, photocrosslinking, and biochemical analyses revealed that PUMA SAHBs engage an α1/α6 trigger site on BAX to initiate its functional activation. We further demonstrated that a cell-permeable PUMA SAHB analog induces apoptosis in neuroblastoma cells and, like expressed PUMA protein, engages BCL-2, MCL-1 and BAX. Thus, we find that PUMA BH3 is a dual anti-apoptotic inhibitor and pro-apoptotic direct activator, and its mimetics may serve as effective pharmacologic triggers of apoptosis in resistant human cancers. PMID:23890007

  4. Chelerythrine down regulates expression of VEGFA, BCL2 and KRAS by arresting G-Quadruplex structures at their promoter regions

    Science.gov (United States)

    Jana, Jagannath; Mondal, Soma; Bhattacharjee, Payel; Sengupta, Pallabi; Roychowdhury, Tanaya; Saha, Pranay; Kundu, Pallob; Chatterjee, Subhrangsu

    2017-01-01

    A putative anticancer plant alkaloid, Chelerythrine binds to G-quadruplexes at promoters of VEGFA, BCL2 and KRAS genes and down regulates their expression. The association of Chelerythrine to G-quadruplex at the promoters of these oncogenes were monitored using UV absorption spectroscopy, fluorescence anisotropy, circular dichroism spectroscopy, CD melting, isothermal titration calorimetry, molecular dynamics simulation and quantitative RT-PCR technique. The pronounced hypochromism accompanied by red shifts in UV absorption spectroscopy in conjunction with ethidium bromide displacement assay indicates end stacking mode of interaction of Chelerythrine with the corresponding G-quadruplex structures. An increase in fluorescence anisotropy and CD melting temperature of Chelerythrine-quadruplex complex revealed the formation of stable Chelerythrine-quadruplex complex. Isothermal titration calorimetry data confirmed that Chelerythrine-quadruplex complex formation is thermodynamically favourable. Results of quantative RT-PCR experiment in combination with luciferase assay showed that Chelerythrine treatment to MCF7 breast cancer cells effectively down regulated transcript level of all three genes, suggesting that Chelerythrine efficiently binds to in cellulo quadruplex motifs. MD simulation provides the molecular picture showing interaction between Chelerythrine and G-quadruplex. Binding of Chelerythrine with BCL2, VEGFA and KRAS genes involved in evasion, angiogenesis and self sufficiency of cancer cells provides a new insight for the development of future therapeutics against cancer.

  5. In vivo therapy of a murine B cell tumor (BCL1) using antibody-ricin A chain immunotoxins

    International Nuclear Information System (INIS)

    Krolick, K.A.; Uhr, J.W.; Slavin, S.; Vitetta, E.S.

    1982-01-01

    Prolonged remissions were induced in mice bearing advanced BCL1 tumors by the combined approach of nonspecific cytoreductive therapy and administration of a tumor-reactive immunotoxin. Thus, the vast majority of the tumor cells (approximately 95%) were first killed by nonspecific cytoreductive therapy using total lymphoid irradiation (TLI) and splenectomy. The residual tumor cells were then eliminated by intravenous administration of an anti-delta immunotoxin. In three of four experiments, all animals treated in the above fashion appeared tumor free 12-16 wk later. In one experiment, blood cells from the mice in remission were transferred to normal BALB/c recipients, and the latter animals have not developed detectable tumor for the 6 mo of observation. Because 1-10 adoptively transferred BCL1 cells will cause tumor in normal BALB/c mice by 12 wk, the inability to transfer tumor to recipients might indicate that the donor animals were tumor free. In the remainder of the animals treated with the tumor-reactive immunotoxin there was a substantial remission in all animals, but the disease eventually reappeared. In contrast, all mice treated with the control immunotoxin or antibody alone relapsed significantly earlier

  6. Hsp90 inhibitor 17-AAG sensitizes Bcl-2 inhibitor (-)-gossypol by suppressing ERK-mediated protective autophagy and Mcl-1 accumulation in hepatocellular carcinoma cells.

    Science.gov (United States)

    Wang, Bin; Chen, Linfeng; Ni, Zhenhong; Dai, Xufang; Qin, Liyan; Wu, Yaran; Li, Xinzhe; Xu, Liang; Lian, Jiqin; He, Fengtian

    2014-11-01

    Natural BH3-memitic (-)-gossypol shows promising antitumor efficacy in several kinds of cancer. However, our previous studies have demonstrated that protective autophagy decreases the drug sensitivities of Bcl-2 inhibitors in hepatocellular carcinoma (HCC) cells. In the present study, we are the first to report that Hsp90 inhibitor 17-AAG enhanced (-)-gossypol-induced apoptosis via suppressing (-)-gossypol-triggered protective autophagy and Mcl-1 accumulation. The suppression effect of 17-AAG on autophagy was mediated by inhibiting ERK-mediated Bcl-2 phosphorylation while was not related to Beclin1 or LC3 protein instability. Meanwhile, 17-AAG downregulated (-)-gossypol-triggered Mcl-1 accumulation by suppressing Mcl-1(Thr163) phosphorylation and promoting protein degradation. Collectively, our study indicates that Hsp90 plays an important role in tumor maintenance and inhibition of Hsp90 may become a new strategy for sensitizing Bcl-2-targeted chemotherapies in HCC cells. Copyright © 2014 Elsevier Inc. All rights reserved.

  7. Immunohistological expression of HIF-1α, GLUT-1, Bcl-2 and Ki-67 in consecutive biopsies during chemoradiotherapy in patients with rectal cancer

    DEFF Research Database (Denmark)

    Havelund, Birgitte Mayland; Sørensen, Flemming Brandt; Pløen, John

    2013-01-01

    The aim of this study was to describe the dynamics of HIF-1α, GLUT-1, Bcl-2 and Ki-67 during chemoradiotherapy (CRT) of rectal cancer, and to investigate the fluctuation of these biomarkers in relation to pathological response to CRT. The study included 86 patients with rectal adenocarcinoma...... receiving preoperative CRT (>50.4 Gy and Uracil/Tegafur). Immunohistological expressions of HIF-1α, GLUT-1, Bcl-2 and Ki-67 were investigated in biopsies taken before treatment, after 2, 4 and 6 weeks of CRT and in specimens from the operation. Decreasing expressions of HIF-1α, Bcl-2 and Ki-67 were observed...... during CRT, whereas GLUT-1 overall was unchanged. No significant changes of the markers were observed in the interval between CRT and surgery. A significant association was observed between the presence of residual carcinoma after 6 weeks of treatment and pathological response to CRT, but no association...

  8. Dynamic Bcl-xL (S49 and (S62 Phosphorylation/Dephosphorylation during Mitosis Prevents Chromosome Instability and Aneuploidy in Normal Human Diploid Fibroblasts.

    Directory of Open Access Journals (Sweden)

    Prasamit Saurav Baruah

    Full Text Available Bcl-xL proteins undergo dynamic phosphorylation/dephosphorylation on Ser49 and Ser62 residues during mitosis. The expression of Bcl-xL(S49A, (S62A and dual (S49/62A phosphorylation mutants in tumor cells lead to severe mitotic defects associated with multipolar spindle, chromosome lagging and bridging, and micro-, bi- and multi-nucleated cells. Because the above observations were made in tumor cells which already display genomic instability, we now address the question: will similar effects occur in normal human diploid cells? We studied normal human diploid BJ foreskin fibroblast cells expressing Bcl-xL (wild type, (S49A, (S49D, (S62A, (S62D and the dual-site (S49/62A and (S49/62D mutants. Cells expressing S49 and/or S62 phosphorylation mutants showed reduced kinetics of cell population doubling. These effects on cell population doubling kinetics correlated with early outbreak of senescence with no impact on the cell death rate. Senescent cells displayed typical senescence-associated phenotypes including high-level of senescence-associated β-galactosidase activity, interleukin-6 (IL-6 secretion, tumor suppressor p53 and cyclin-dependent kinase inhibitor p21Waf1/Cip1 activation as well as γH2A.X-associated nuclear chromatin foci. Fluorescence in situ hybridization analysis and Giemsa-banded karyotypes revealed that the expression of Bcl-xL phosphorylation mutants in normal diploid BJ cells provoked chromosome instability and aneuploidy. These findings suggest that dynamic Bcl-xL(S49 and (S62 phosphorylation/dephosphorylation cycles are important in the maintenance of chromosome integrity during mitosis in normal cells. They could impact future strategies aiming to develop and identify compounds that could target not only the anti-apoptotic domain of Bcl-xL protein, but also its mitotic domain for cancer therapy.

  9. Effects of systemic administration of ciliary neurotrophic factor on Bax and Bcl-2 proteins in the lumbar spinal cord of neonatal rats after sciatic nerve transection

    Directory of Open Access Journals (Sweden)

    A.C.S. Rezende

    2008-11-01

    Full Text Available Ciliary neurotrophic factor (CNTF is a cytokine that plays a neuroprotective role in relation to axotomized motoneurons. We determined the effect of daily subcutaneous doses of CNTF (1.2 µg/g for 5 days; N = 13 or PBS (N = 13 on the levels of mRNA for Bcl-2 and Bax, as well as the expression and inter-association of Bcl-2 and Bax proteins, and the survival of motoneurons in the spinal cord lumbar enlargement of 2-day-old Wistar rats after sciatic nerve transection. Five days after transection, the effects were evaluated on histological and molecular levels using Nissl staining, immunoprecipitation, Western blot analysis, and reverse transcriptase-polymerase chain reaction. The motoneuron survival ratio, defined as the ratio between the number of motoneurons counted on the lesioned side vs those on the unlesioned side, was calculated. This ratio was 0.77 ± 0.02 for CNTF-treated rats vs 0.53 ± 0.02 for the PBS-treated controls (P < 0.001. Treatment with CNTF modified the level of mRNA, with the expression of Bax RNA decreasing 18% (with a consequent decrease in the level of Bax protein, while the expression of Bcl-2 RNA was increased 87%, although the level of Bcl-2 protein was unchanged. The amount of Bcl-2/Bax heterodimer increased 91% over that found in the PBS-treated controls. These data show, for the first time, that the neuroprotective effect of CNTF on neonatal rat axotomized motoneurons is associated with a reduction in free Bax, due to the inhibition of Bax expression, as well as increased Bcl-2/Bax heterodimerization. Thus, the neuroprotective action of the CNTF on axotomized motoneurons can be related to the inhibition of this apoptotic pathway.

  10. Prolactin suppresses a progestin-induced CK5-positive cell population in luminal breast cancer through inhibition of progestin-driven BCL6 expression

    Science.gov (United States)

    Sato, Takahiro; Tran, Thai H.; Peck, Amy R.; Girondo, Melanie A.; Liu, Chengbao; Goodman, Chelain R.; Neilson, Lynn M.; Freydin, Boris; Chervoneva, Inna; Hyslop, Terry; Kovatich, Albert J.; Hooke, Jeffrey A.; Shriver, Craig D.; Fuchs, Serge Y.; Rui, Hallgeir

    2014-01-01

    Prolactin controls the development and function of milk-producing breast epithelia but also supports growth and differentiation of breast cancer, especially luminal subtypes. A principal signaling mediator of prolactin, Stat5, promotes cellular differentiation of breast cancer cells in vitro, and loss of active Stat5 in tumors is associated with anti-estrogen therapy failure in patients. In luminal breast cancer progesterone induces a cytokeratin-5 (CK5)-positive basal cell-like population. This population possesses characteristics of tumor stem cells including quiescence, therapy-resistance, and tumor-initiating capacity. Here we report that prolactin counteracts induction of the CK5-positive population by the synthetic progestin R5020 in luminal breast cancer cells both in vitro and in vivo. CK5-positive cells were chemoresistant as determined by four-fold reduced rate of apoptosis following docetaxel exposure. Progestin-induction of CK5 was preceded by marked up-regulation of BCL6, an oncogene and transcriptional repressor critical for the maintenance of leukemia-initiating cells. Knockdown of BCL6 prevented induction of CK5-positive cell population by progestin. Prolactin suppressed progestin-induced BCL6 through Jak2-Stat5 but not Erk- or Akt-dependent pathways. In premenopausal but not postmenopausal patients with hormone receptor-positive breast cancer, tumor protein levels of CK5 correlated positively with BCL6, and high BCL6 or CK5 protein levels were associated with unfavorable clinical outcome. Suppression of progestin-induction of CK5-positive cells represents a novel pro-differentiation effect of prolactin in breast cancer. The present progress may have direct implications for breast cancer progression and therapy since loss of prolactin receptor-Stat5 signaling occurs frequently and BCL6 inhibitors currently being evaluated for lymphomas may have value for breast cancer. PMID:23708665

  11. Steroid induction of therapy-resistant cytokeratin-5-positive cells in estrogen receptor-positive breast cancer through a BCL6-dependent mechanism

    Science.gov (United States)

    Goodman, C R; Sato, T; Peck, A R; Girondo, M A; Yang, N; Liu, C; Yanac, A F; Kovatich, A J; Hooke, J A; Shriver, C D; Mitchell, E P; Hyslop, T; Rui, H

    2016-01-01

    Therapy resistance remains a major problem in estrogen receptor-α (ERα)-positive breast cancer. A subgroup of ERα-positive breast cancer is characterized by mosaic presence of a minor population of ERα-negative cancer cells expressing the basal cytokeratin-5 (CK5). These CK5-positive cells are therapy resistant and have increased tumor-initiating potential. Although a series of reports document induction of the CK5-positive cells by progestins, it is unknown if other 3-ketosteroids share this ability. We now report that glucocorticoids and mineralocorticoids effectively expand the CK5-positive cell population. CK5-positive cells induced by 3-ketosteroids lacked ERα and progesterone receptors, expressed stem cell marker, CD44, and displayed increased clonogenicity in soft agar and broad drug-resistance in vitro and in vivo. Upregulation of CK5-positive cells by 3-ketosteroids required induction of the transcriptional repressor BCL6 based on suppression of BCL6 by two independent BCL6 small hairpin RNAs or by prolactin. Prolactin also suppressed 3-ketosteroid induction of CK5+ cells in T47D xenografts in vivo. Survival analysis with recursive partitioning in node-negative ERα-positive breast cancer using quantitative CK5 and BCL6 mRNA or protein expression data identified patients at high or low risk for tumor recurrence in two independent patient cohorts. The data provide a mechanism by which common pathophysiological or pharmacologic elevations in glucocorticoids or other 3-ketosteroids may adversely affect patients with mixed ERα+/CK5+ breast cancer. The observations further suggest a cooperative diagnostic utility of CK5 and BCL6 expression levels and justify exploring efficacy of inhibitors of BCL6 and 3-ketosteroid receptors for a subset of ERα-positive breast cancers. PMID:26096934

  12. [Effect of leptin on expression of calpain-1 and Bcl-2 and apoptosis in myocardial tissue of neonatal rats after asphyxia].

    Science.gov (United States)

    Wu, Dan-Dan; Wu, Xing-Heng; Zhang, Li-Na

    2016-10-01

    To study the effect of leptin on the expression of calcium-activated neutral protease 1 (calpain-1) and B cell lymphoma-2 (Bcl-2) and apoptosis in the myocardial tissue of neonatal rats after asphyxia. A total of 48 neonatal rats were randomly and equally divided into normal control group, asphyxia group, leptin treatment groups, and calpain-1 inhibitor (CAI-1) group. The neonatal rat model of asphyxia under normal atmospheric condition was established in all groups except the control group. For the leptin treatment groups, rats received 20, 80, and 160 μg/kg leptin by intraperitoneal injection immediately after model establishment, respectively. For the CAI-1 group, rats received 10 mg/kg CAI-1 by intraperitoneal injection immediately after model establishment. For all the groups, the myocardial tissue was collected at 2 hours after model establishment. Immunohistochemistry was used to measure the expression of calpain-1 and Bcl-2. The TUNEL method was used to evaluate apoptosis of myocardial cells. The expression of calpain-1 and Bcl-2 and apoptosis index (AI) were significantly higher in the asphyxia group than in the normal control group (P˂0.05). The leptin treatment groups and the CAI-1 group had significantly lower expression of calpain-1, significantly lower AI, and significantly higher expression of Bcl-2 than the asphyxia group (P˂0.05). The CAI-1 group had the largest changes in all the indices compared with the asphyxia group. However, there were no significant differences in all indices between the 160 μg/kg leptin treatment group and the CAI-1 group. After asphyxia, the expression of calpain-1 was positively correlated with AI, while the expression of Bcl-2 was negatively correlated with AI and the expression of calpain-1 (P˂0.05). Leptin reduces apoptosis of myocardial cells in asphyxiated neonatal rats by the inhibition of calpain-1 activation and upregulation of Bcl-2 expression.

  13. Expression of p53 and bcl-2 and response to preoperative chemotherapy and radiotherapy for locally advanced squamous cell carcinoma of the oesophagus

    International Nuclear Information System (INIS)

    Puglisi, F.; Di Loreto, C.; Panizzo, R.; Avellini, C.; Cacitti, V.; Beltrami, C.A.; Fongione, S.

    1996-01-01

    The aims were to investigate the immunohistochemical expression of p53 and bcl-2 proteins in squamous cell carcinoma (SCC) of the oesophagus and to assess whether expression of these oncoproteins can be used to stratify patients into groups with a favourable or unfavourable response to preoperative chemo/radiotherapy. This study confirms the observation that p53 protein is frequently expressed in SCCs of the oesophagus, probably as a result of a mutation of the TP53 gene. However, no significant association was found between oncoprotein expression and response to chemo/radiotherapy. Anticancer agents do not seem to modify the expression of p53 and bcl-2 proteins. (Author)

  14. Prognostic significance of bcl-2 expression in stage III breast cancer patients who had received doxorubicin and cyclophosphamide followed by paclitaxel as adjuvant chemotherapy

    International Nuclear Information System (INIS)

    Lee, Kyung-Hun; Noh, Dong-Young; Heo, Dae Seog; Ha, Sung Whan; Bang, Yung-Jue; Im, Seock-Ah; Oh, Do-Youn; Lee, Se-Hoon; Chie, Eui Kyu; Han, Wonshik; Kim, Dong-Wan; Kim, Tae-You; Park, In Ae

    2007-01-01

    Bcl-2 is positively regulated by hormonal receptor pathways in breast cancer. A study was conducted to assess the prognostic significances of clinico-pathologic variables and of ER, PR, p53, c-erbB2, bcl-2, or Ki-67 as markers of relapse in breast cancer patients who had received the identical adjuvant therapy at a single institution. A cohort of 151 curatively resected stage III breast cancer patients (M:F = 3:148, median age 46 years) who had 4 or more positive lymph nodes and received doxorubicin and cyclophosphamide followed by paclitaxel (AC/T) as adjuvant chemotherapy was analyzed for clinico-pathologic characteristics including disease-free survival (DFS) and overall survival (OS). Patients with positive ER and/or PR expression received 5 years of tamoxifen following AC/T. The protein expressions of biomarkers were assessed immunohistochemically. The median follow-up duration was 36 months, and 37 patients (24.5%) experienced a recurrence. Univariate analyses indicated that the tumor size (P = 0.038) and the number of involved lymph nodes (P < 0.001) significantly affected the recurrences. However, the type of surgery, the histology, histologic grade, the presence of endolymphatic emboli, and a close resection margin did not. Moreover, ER positivity (P = 0.013), bcl-2 positivity (P = 0.002) and low p53 expression (P = 0.032) were found to be significantly associated with a prolonged DFS. Furthermore, multivariate analysis identified 10 or more involved lymph nodes (HR 7.366; P < 0.001), negative bcl-2 expression (HR 2.895; P = 0.030), and c-erbB2 over-expression (HR 3.535; P = 0.001) as independent indicators of poorer DFS. In addition, bcl-2 expression was found to be significantly correlated with the expressions of ER and PR, and inversely correlated with the expressions of p53, c-erbB2 and Ki-67. Patients with bcl-2 expression had a significantly longer DFS than those without, even in the ER (+) subgroup. Moreover, OS was significantly affected by ER, bcl

  15. MicroRNA-184 inhibits proliferation and promotes apoptosis of human colon cancer SW480 and HCT116 cells by downregulating C-MYC and BCL-2.

    Science.gov (United States)

    Wang, Yong-Bing; Zhao, Xiao-Hui; Li, Gang; Zheng, Jun-Hua; Qiu, Wei

    2018-02-01

    This study aimed to investigate the effects of microRNA-184 (miR-184) on the proliferation and apoptosis of human colon cancer cells through the regulation of C-MYC and BCL-2. Human colon cancer tissues were selected as case group, and adjacent normal tissues were as control group. Human colon cancer SW480 and HCT116 cells were allocated into blank, miR-184 mimic negative control (mimic-NC), miR-184 inhibitor NC (inhibitor-NC), miR-184 mimic, and miR-184 inhibitor groups. Flow cytometry, Annexin V/PI and MTT assay were used to examine the cell cycle, apoptosis and viability. The expressions of C-MYC, BCL-2 and miR-184 were detected via immunohistochemistry, Western blotting and reverse transcription quantitative polymerase chain reaction (RT-qPCR). C-MYC and BCL-2 were direct targets to miR-184. The growth of colon cancer cells in the miR-184 mimic group was inhibited and exhibited an increase in apoptosis. Cell growth in the miR-184 mimic group was increased in addition to the inhibition of apoptosis. Compared with miR-184 mimic group, the expressions of C-MYC and BCL-2 in miR-184 inhibitor group were increased. The expressions of C-MYC and BCL-2 in colon cancer tissues exhibited high levels of expression, while miR-184 displayed relatively low levels in comparison to the adjacent normal tissues. An association was detected regarding the expressions of miR-184, C-MYC and BCL-2 with the differentiation, invasion depth and lymph node metastasis. MiR-184 expression was negatively related to C-MYC and BCL-2 expressions. Our study suggested that miR-184 could inhibit proliferation and promote apoptosis of colon cancer cells by down-regulating expressions of C-MYC and BCL-2. © 2017 Wiley Periodicals, Inc.

  16. Protein expression of B-cell lymphoma gene 6 (BCL-6) in invasive breast cancer is associated with cyclin D1 and hypoxia-inducible factor-1α (HIF-1α)

    NARCIS (Netherlands)

    Bos, R.; Diest, P.J. van; Groep, P. van der; Greijer, A.E.; Hermsen, M.A.J.A.; Heijnen, I.; Meijer, G.A.; Baak, J.P.A.; Pinedo, H.M.; Wall, E. van der; Shvarts, A.

    2003-01-01

    B-cell lymphoma gene (BCL-6) upregulation contributes to immortalization of mouse embryo fibroblast and primary B cells via upregulation of cyclin D1. As cyclin D1 overexpression is a common phenomenon in different cancers, BCL-6 protein overexpression may not be restricted to lymphomas. In this

  17. Critical role of pro-apoptotic Bcl-2 family members in andrographolide-induced apoptosis in human cancer cells.

    Science.gov (United States)

    Zhou, Jing; Zhang, Siyuan; Ong, Choon-Nam; Shen, Han-Ming

    2006-07-14

    Andrographolide (Andro), a diterpenoid lactone isolated from a traditional herbal medicine Andrographis paniculata, is known to possess potent anti-inflammatory activity. In this study, Andro induced apoptosis in human cancer cells via activation of caspase 8 in the extrinsic death receptor pathway and subsequently with the participation of mitochondria. Andro triggered a caspase 8-dependent Bid cleavage, followed by a series of sequential events including Bax conformational change and mitochondrial translocation, cytochrome c release from mitochondria, and activation of caspase 9 and 3. Inhibition of caspase 8 blocked Bid cleavage and Bax conformational change. Consistently, knockdown of Bid protein using small interfering RNA (siRNA) technique suppressed Andro-induced Bax conformational change and apoptosis. In conclusion, the pro-apoptotic Bcl-2 family members (Bid and Bax) are the key mediators in relaying the cell death signaling initiated by Andro from caspase 8 to mitochondria and then to downstream effector caspases, and eventually leading to apoptotic cell death.

  18. Manganese activates the mitochondrial apoptotic pathway in rat astrocytes by modulating the expression of proteins of the Bcl-2 family.

    Science.gov (United States)

    Gonzalez, Laura E; Juknat, A Ana; Venosa, Andrea J; Verrengia, Noemi; Kotler, Mónica L

    2008-12-01

    Manganese induces the central nervous system injury leading to manganism, by mechanisms not completely understood. Chronic exposure to manganese generates oxidative stress and induces the mitochondrial permeability transition. In the present study, we characterized apoptotic cell death mechanisms associated with manganese toxicity in rat cortical astrocytes and demonstrated that (i) Mn treatment targets the mitochondria and induces mitochondrial membrane depolarization followed by cytochrome c release to the cytoplasm, (ii) Mn induces both effector caspases 3/7 and 6 as well as PARP-1 cleavage and (iii) Mn shifts the balance of cell death/survival of Bcl-2 family proteins to favor the apoptotic demise of astrocytes. Our model system using cortical rat astrocytes treated with Mn would emerge as a good tool for investigations aimed to elucidate the role of apoptosis in manganism.

  19. MicroRNA-10b downregulation mediates acute rejection of renal allografts by derepressing BCL2L11

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Xiaoyou [Department of Organ Transplantation, Zhujiang Hospital, Guangzhou 510282 (China); Dong, Changgui [Institute of Molecular Ecology and Evolution, East China Normal University, Shanghai 200062 (China); Jiang, Zhengyao [Department of Organ Transplantation, Zhujiang Hospital, Guangzhou 510282 (China); Wu, William K.K. [Department of Anaesthesia and Intensive Care, The Chinese University of Hong Kong, Shatin, NT, Hong Kong (China); State Key Laboratory of Digestive Diseases, LKS Institute of Health Sciences, The Chinese University of Hong Kong, Shatin, NT, Hong Kong (China); Chan, Matthew T.V. [Department of Anaesthesia and Intensive Care, The Chinese University of Hong Kong, Shatin, NT, Hong Kong (China); Zhang, Jie [Department of Organ Transplantation, Zhujiang Hospital, Guangzhou 510282 (China); Li, Haibin; Qin, Ke [Guangxi Key Laboratory for Transplantation Medicine Department of Organ Transplantation in Guangzhou Military Region, Institute of Transplant Medicine, 303 Hospital of People' s Liberation Army, Nanning, Guangxi 530021 (China); Sun, Xuyong, E-mail: sunxuyong0528@163.com [Guangxi Key Laboratory for Transplantation Medicine Department of Organ Transplantation in Guangzhou Military Region, Institute of Transplant Medicine, 303 Hospital of People' s Liberation Army, Nanning, Guangxi 530021 (China)

    2015-04-10

    Kidney transplantation is the major therapeutic option for end-stage kidney diseases. However, acute rejection could cause allograft loss in some of these patients. Emerging evidence supports that microRNA (miRNA) dysregulation is implicated in acute allograft rejection. In this study, we used next-generation sequencing to profile miRNA expression in normal and acutely rejected kidney allografts. Among 75 identified dysregulated miRNAs, miR-10b was the most significantly downregulated miRNAs in rejected allografts. Transfecting miR-10b inhibitor into human renal glomerular endothelial cells recapitulated key features of acute allograft rejection, including endothelial cell apoptosis, release of pro-inflammatory cytokines (interleukin-6, tumor necrosis factor α, interferon-γ, and chemokine (C–C motif) ligand 2) and chemotaxis of macrophages whereas transfection of miR-10b mimics had opposite effects. Downregulation of miR-10b directly derepressed the expression of BCL2L11 (an apoptosis inducer) as revealed by luciferase reporter assay. Taken together, miR-10b downregulation mediates many aspects of disease pathogenicity of acute kidney allograft rejection. Restoring miR-10b expression in glomerular endothelial cells could be a novel therapeutic approach to reduce acute renal allograft loss. - Highlights: • miR-10b was the most downregulated microRNAs in acutely rejected renal allografts. • miR-10b downregulation triggered glomerular endothelial cell apoptosis. • miR-10b downregulation induced release of pro-inflammatory cytokines. • miR-10b downregulation derepressed its pro-apoptotic target BCL2L11.

  20. Pim kinases phosphorylate multiple sites on Bad and promote 14-3-3 binding and dissociation from Bcl-XL

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    Hastie C James

    2006-01-01

    Full Text Available Abstract Background Pim-1, 2 and 3 are a group of enzymes related to the calcium calmodulin family of protein kinases. Over-expression of Pim-1 and Pim-2 in mice promotes the development of lymphomas, and up-regulation of Pim expression has been observed in several human cancers. Results Here we show that the pim kinases are constitutively active when expressed in HEK-293 cells and are able to phosphorylate the Bcl-2 family member Bad on three residues, Ser112, Ser136 and Ser155 in vitro and in cells. In vitro mapping showed that Pim-2 predominantly phosphorylated Ser112, while Pim-1 phosphorylated Ser112, but also Ser136 and Ser155 at a reduced rate compared to Ser112. Pim-3 was found to be the least specific for Ser112, and the most effective at phosphorylating Ser136 and Ser155. Pim-3 was also able to phosphorylate other sites in Bad in vitro, including Ser170, another potential in vivo site. Mutation of Ser136 to alanine prevented the phosphorylation of Ser112 and Ser155 by Pim kinases in HEK-293 cells, suggesting that this site must be phosphorylated first in order to make the other sites accessible. Pim phosphorylation of Bad was also found to promote the 14-3-3 binding of Bad and block its association with Bcl-XL. Conclusion All three Pim kinase family members predominantly phosphorylate Bad on Ser112 and in addition are capable of phosphorylating Bad on multiple sites associated with the inhibition of the pro-apoptotic function of Bad in HEK-293 cells. This would be consistent with the proposed function of Pim kinases in promoting cell proliferation and preventing cell death.

  1. Electroporation increases antitumoral efficacy of the bcl-2 antisense G3139 and chemotherapy in a human melanoma xenograft

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    Baldi Alfonso

    2011-07-01

    Full Text Available Abstract Background Nucleic acids designed to modulate the expression of target proteins remain a promising therapeutic strategy in several diseases, including cancer. However, clinical success is limited by the lack of efficient intracellular delivery. In this study we evaluated whether electroporation could increase the delivery of antisense oligodeoxynucleotides against bcl-2 (G3139 as well as the efficacy of combination chemotherapy in human melanoma xenografts. Methods Melanoma-bearing nude mice were treated i.v. with G3139 and/or cisplatin (DDP followed by the application of trains of electric pulses to tumors. Western blot, immunohistochemistry and real-time PCR were performed to analyze protein and mRNA expression. The effect of electroporation on muscles was determined by histology, while tumor apoptosis and the proliferation index were analyzed by immunohistochemistry. Antisense oligodeoxynucleotides tumor accumulation was measured by FACS and confocal microscopy. Results The G3139/Electroporation combined therapy produced a significant inhibition of tumor growth (TWI, more than 50% accompanied by a marked tumor re-growth delay (TRD, about 20 days. The efficacy of this treatment was due to the higher G3139 uptake in tumor cells which led to a marked down-regulation of bcl-2 protein expression. Moreover, the G3139/EP combination treatment resulted in an enhanced apoptotic index and a decreased proliferation rate of tumors. Finally, an increased tumor response was observed after treatment with the triple combination G3139/DDP/EP, showing a TWI of about 75% and TRD of 30 days. Conclusions These results demonstrate that electroporation is an effective strategy to improve the delivery of antisense oligodeoxynucleotides within tumor cells in vivo and it may be instrumental in optimizing the response of melanoma to chemotherapy. The high response rate observed in this study suggest to apply this strategy for the treatment of melanoma patients.

  2. Bcl-2 antagonists interact synergistically with bortezomib in DLBCL cells in association with JNK activation and induction of ER stress.

    Science.gov (United States)

    Dasmahapatra, Girija; Lembersky, Dmitry; Rahmani, Mohamed; Kramer, Lora; Friedberg, Jonathan; Fisher, Richard I; Dent, Paul; Grant, Steven

    2009-05-01

    Mechanisms underlying interactions between the proteasome inhibitor bortezomib and small molecule Bcl-2 antagonists were examined in GC- and ABC-type human DLBCL (diffuse lymphocytic B-cell lymphoma) cells. Concomitant or sequential exposure to non- or minimally toxic concentrations of bortezomib or other proteasome inhibitors and either HA14-1 or gossypol resulted in a striking increase in Bax/Bak conformational change/translocation, cytochrome c release, caspase activation and synergistic induction of apoptosis in both GC- and ABC-type cells. These events were associated with a sharp increase in activation of the stress kinase JNK and evidence of ER stress induction (e.g., eIF2alpha phosphorylation, activation of caspases-2 and -4, and Grp78 upregulation). Pharmacologic or genetic (e.g., shRNA knockdown) interruption of JNK signaling attenuated HA14-1/bortezomib lethality and ER stress induction. Genetic disruption of the ER stress pathway (e.g., in cells expressing caspase-4 shRNA or DN-eIF2alpha) significantly attenuated lethality. The toxicity of this regimen was independent of ROS generation. Finally, HA14-1 significantly increased bortezomib-mediated JNK activation, ER stress induction, and lethality in bortezomib-resistant cells. Collectively these findings indicate that small molecule Bcl-2 antagonists promote bortezomib-mediated mitochondrial injury and lethality in DLBCL cells in association with enhanced JNK activation and ER stress induction. They also raise the possibility that such a strategy may be effective in different DLBCL sub-types (e.g., GC- or ABC), and in bortezomib-resistant disease.

  3. [Bcl-2 inhibitor ABT-737 enhances the cisplatin-induced apoptosis in breast cancer T47D cells].

    Science.gov (United States)

    Chen, Zu-jin; Zhang, Bin; Pan, Si-hu; Zhao, Hong-meng; Zhang, Yue; Feng, Wei-hong; Li, Yuan-yuan; Cao, Xu-chen

    2011-12-01

    To study the effect of ABT-737 combined with cisplatin on apoptosis of breast cancer cell line T47D cells. T47D cells cultured in vitro was used for this experiment. Cell proliferation was measured by MTT assay. The expression of apoptosis-related protein was determined by Western blot. Morphological changes of apoptotic cells were observed by fluorescence microscopy. The apoptosis rate was examined by flow cytometry. The MTT assay showed that ABT-737 significantly decreased the IC(50) of cisplatin in T47D cells [(26.00 ± 1.41) µmol/L of single cisplatin vs. (13.00 ± 1.11) µmol/L of combination (ABT-737 + cisplatin)]. As a single agent, ABT-737 did not inhibit the proliferation of T47D cells, but enhanced the inhibitory effect of cisplatin in a dose-dependent manner. The detection of the cleavage of PARP showed that ABT-737 lowered the doses of cisplatin to induce apoptosis and shortened the induction time of apoptosis in T47D cells. Compared with the single use of cisplatin, the combination of ABT-737 and cisplatin accelerated the cleavage of PARP and caspase3, but did not alter the expression levels of Bcl-2, Bcl-X(L), and Bax. Both flow cytometry and fluorescence microscopy showed that ABT-737 combined with cisplatin significantly increased the apoptosis induction in T47D cells (2.3% ± 0.1 % in the control, 30.0% ± 0.8% in the cisplatin alone, and 49.0% ± 0.5% in the cisplatin + ABT-737 groups, P cisplatin-induced apoptosis in human breast cancer T47D cells in vitro.

  4. Expression of Fas and Bcl-2 and their relationship to apoptosis in spleen lymphocytes of mice irradiated with large dose 60Co γ-rays

    International Nuclear Information System (INIS)

    Gao Linlu; Cui Yufang; Yang Hong; Xia Guowei; Peng Ruiyun; Gao Yabin; Wang Dewen

    2000-01-01

    Objective: To investigate the expressions of Fas and Bcl-2 and their significance in apoptosis of spleen lymphocyte of mice after large dose γ-ray irradiation. Methods: At 3,6,12,24 h, 3, 7, 14 and 28 d after 6-20 Gy γ-ray irradiation mice were sacrificed and their spleens were removed. The expressions of Fas and Bcl-2 oncoprotein were analysed by LSAB immunohistochemical method. Results: The expression of Fas was strongly positive at 6 h after irradiation, especially in 6-12 Gy groups. It become less obvious along with prolongation of time after irradiation and almost disappeared on d 7 after irradiation. The expression of Bcl-2 was nearly negative at 6 h after irradiation, especially in 12-20 Gy groups, and did not recover on d 28 after irradiation. Conclusion: After large dose γ-ray irradiation the expression of Fas in mouse spleen lymphocytes shows a better relationship to lymphocyte apoptosis; in other words, Fas can prompt apoptosis. On the other hand, the action of Bcl-2 is reduced or even disappeared. Both of them play an important role in spleen lymphocyte apoptosis after large dose of γ-irradiation

  5. Comparison of EMA,CEA, CD10 and Bcl-2 Biomarkers by Immunohistochemistry in Squamous Cell Carcinoma and Basal Cell Carcinoma of the Skin.

    Science.gov (United States)

    Ramezani, Mazaher; Mohamadzaheri, Elham; Khazaei, Sedigheh; Najafi, Farid; Vaisi-Raygani, Asad; Rahbar, Mahtab; Sadeghi, Masoud

    2016-01-01

    Basal and squamous cell carcinoma (BCC and SCC) are the most common skin cancers worldwide and distinction between the two may sometimes be very difficult in routine histopathology. The present study was aimed to evaluate a reliable diagnostic method for these cancers based on immunohistochemistry (IHC). IHC was used with antibodies to Bcl-2, CD10, CEA, and EMA biomarkers, which despite non-specificity are easily available for detection of various types of tumors in pathology sections and can be used as a panel for differentiation. In this descriptive and analytic study, paraffin- embedded blocks of 29 SCC patients and 29 BCC patients were collected and sectioned for IHC staining. The results were analyzed by the STATA (version 8) statistical package using the Chi-square test. BCC patients were 100%, 75.8%, 0% and 0% positive for Bcl-2, CD10, CEA and EMA markers, respectively, and for SCC patients were 3.5%, 0%, 34.5% and 82.7% positive, respectively. Using simultaneously Bcl-2 and CD10 as positive markers, detection of BCC with 88% accuracy and 100% specificity was possible, while application of CEA and EMA positivity could detect SCC with 67% accuracy and 100% specificity. SCC and BCC have different immunostaining profiles; therefore, Bcl-2, CD10, CEA and EMA markers can be helpful to distinguish between them.

  6. Effects of low dose radiation on tumor apoptosis, cell cycle progression and changes of apoptosis-related protein bcl-2 in tumor-bearing mice

    International Nuclear Information System (INIS)

    Yu Hongsheng; Fei Conghe; Shen Fangzhen; Liang Jun

    2003-01-01

    Objective: To study the effect of low dose radiation (LDR) on tumor apoptosis, cell cycle progression and changes of apoptosis-related protein bcl-2 in tumor-bearing mice. Methods: Kunming stain male mice were implanted with S180 sarcoma cells in the left inguen subcutaneously as an in situ experimental animal model. Seven days after implantation, the mice were given 75 mGy whole-body γ-irradiation. At 24 and 48 h after irradiation, all mice were sacrificed to measure the tumor volume, and tumor cell apoptosis, cell cycle progression were analyzed by flow cytometry. The expression of apoptosis-related protein bcl-2 and the apoptotic rate of tumor cells were observed by immunohistochemistry and electron microscopy. Results: Tumor growth was significantly slowed down after LDR (P 1 phase and the expression of bcl-2 protein decreased at 24 h. Apoptotic rate of tumor cells increased significantly at 48 h after LDR. Conclusion: LDR could cause a G 1 -phase arrest and increase the apoptosis of tumor cells through the low level of apoptosis-related protein bcl-2 in the tumor-bearing mice. The organized immune function and anti-tumor ability are markedly increased after LDR. The study provides practical evidence of clinical application to cancer treatment

  7. Involvement of Bax and Bcl2 in Neuroprotective Effect of Curcumin in Kainic Acid-Induced Model of Temporal Lobe Epilepsy in Male Rat

    Directory of Open Access Journals (Sweden)

    zahra Kiasalari

    2016-04-01

    Full Text Available Background & objectives: Temporal lobe epilepsy is associated with neuronal apoptosis. Curcumin has antioxidant and anticonvulsant activities, therefore this study was conducted to assess involvement of Bax and Bcl2 in protective effect of curcumin in epileptic rats. Methods: 28 rats were divided into sham, curcumin-pretreated sham, epileptic (kainate, and curcumin-pretreated epileptic groups. Experimental model of epilepsy was induced by intrahippocampal administration of kainic acid. Rats received curcumin at a dose of 100 mg/kg. Finally, Nissl staining and Bax and Bcl2 immunohistochemistry were conducted on hippocampal sections and data were analyzed using one-way ANOVA and unpaired t-test. The p-value less than 0.05was considered statistically significant. Results: Induction of epilepsy was followed by a significant seizure and curcumin pretreatment significantly reduced seizure intensity (p<0.01. In addition, there were no significant differences between the groups in Nissl staining of CA3 area neurons. In addition, Bax positive neurons were observed in CA3 area in kainate group and significantly decreased in curcumin pretreated rats (p<0.05. Meanwhile, Bcl2 positive neurons were also moderately observed in kainate group and curcumin pretreatment significantly increased it (p<0.05. Conclusion: Curcumin pretreatment exhibits anticonvulsant activity in epileptic rats. It also decreases the expression of pro-apoptotic protein Bax and significantly enhances the expression of anti-apoptotic protein Bcl2 and hence could reduce neuronal apoptosis.

  8. Effects of Helicobacter pylori infection on the expressions of Bax and Bcl-2 in patients with chronic gastritis and gastric cancer.

    Science.gov (United States)

    Bartchewsky, Waldemar; Martini, Mariana R; Squassoni, Aline C; Alvarez, Marisa C; Ladeira, Marcelo S P; Salvatore, Daisy M F; Trevisan, Miriam A; Pedrazzoli, José; Ribeiro, Marcelo L

    2010-01-01

    The aim of the present study is to evaluate the influence of Helicobacter pylori on Bax and Bcl-2 mRNA and protein levels in patients with chronic gastritis and gastric cancer. The study included 217 patients, of which 26 were uninfected; 127 had chronic gastritis and were H. pylori-positive, and 64 had gastric cancer. Bacterial genotypes were evaluated by PCR, and the expression values were determined by quantitative real-time PCR and immunohistochemistry. Our data showed that the up-regulationary effects of H. pylori infection on the pro-apoptotic gene, Bax, were stronger than its induction of Bcl-2; this effect may increase apoptosis in patients with chronic gastritis. In patients with gastric cancer, the up-regulation of the anti-apoptotic gene, Bcl-2, counteracted the pro-apoptotic effects of Bax, leading to a deregulation of apoptosis-associated gene expression, favoring cell proliferation. Thus, the disturbance in Bax and Bcl-2 balance, induced by H. pylori, might be important in gastric cancer development.

  9. Editor's Highlight: Periodic Exposure to Smartphone-Mimic Low-Luminance Blue Light Induces Retina Damage Through Bcl-2/BAX-Dependent Apoptosis.

    Science.gov (United States)

    Lin, Cheng-Hui; Wu, Man-Ru; Li, Ching-Hao; Cheng, Hui-Wen; Huang, Shih-Hsuan; Tsai, Chi-Hao; Lin, Fan-Li; Ho, Jau-Der; Kang, Jaw-Jou; Hsiao, George; Cheng, Yu-Wen

    2017-05-01

    Blue light-induced phototoxicity plays an important role in retinal degeneration and might cause damage as a consequence of smartphone dependency. Here, we investigated the effects of periodic exposure to blue light-emitting diode in a cell model and a rat retinal damage model. Retinal pigment epithelium (RPE) cells were subjected to blue light in vitro and the effects of blue light on activation of key apoptotic pathways were examined by measuring the levels of Bcl-2, Bax, Fas ligand (FasL), Fas-associated protein with death domain (FADD), and caspase-3 protein. Blue light treatment of RPE cells increased Bax, cleaved caspase-3, FasL, and FADD expression, inhibited Bcl-2 and Bcl-xL accumulation, and inhibited Bcl-2/Bax association. A rat model of retinal damage was developed with or without continuous or periodic exposure to blue light for 28 days. In this rat model of retinal damage, periodic blue light exposure caused fundus damage, decreased total retinal thickness, caused atrophy of photoreceptors, and injured neuron transduction in the retina. © The Author 2017. Published by Oxford University Press on behalf of the Society of Toxicology. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  10. Prognostic value of Bcl-2 in two independent populations of estrogen receptor positive breast cancer patients treated with adjuvant endocrine therapy

    DEFF Research Database (Denmark)

    Larsen, Mathilde S; Bjerre, Karsten; Giobbie-Hurder, Anita

    2012-01-01

    Estrogen receptor (ER) status is not an optimal marker for response to adjuvant endocrine therapy since approximately 30% of patients with ER-positive tumors eventually relapse. Bcl-2 is regulated by ER and may thus be considered as an indicator of ER activity and a candidate supplementary marker...

  11. Structural changes in the BH3 domain of SOUL protein upon interaction with the anti-apoptotic protein Bcl-xL.

    Science.gov (United States)

    Ambrosi, Emmanuele; Capaldi, Stefano; Bovi, Michele; Saccomani, Gianmaria; Perduca, Massimiliano; Monaco, Hugo L

    2011-09-01

    The SOUL protein is known to induce apoptosis by provoking the mitochondrial permeability transition, and a sequence homologous with the BH3 (Bcl-2 homology 3) domains has recently been identified in the protein, thus making it a potential new member of the BH3-only protein family. In the present study, we provide NMR, SPR (surface plasmon resonance) and crystallographic evidence that a peptide spanning residues 147-172 in SOUL interacts with the anti-apoptotic protein Bcl-xL. We have crystallized SOUL alone and the complex of its BH3 domain peptide with Bcl-xL, and solved their three-dimensional structures. The SOUL monomer is a single domain organized as a distorted β-barrel with eight anti-parallel strands and two α-helices. The BH3 domain extends across 15 residues at the end of the second helix and eight amino acids in the chain following it. There are important structural differences in the BH3 domain in the intact SOUL molecule and the same sequence bound to Bcl-xL.

  12. Expression of Bcl-2 and epithelial growth factor receptor proteins in keratocystic odontogenic tumor in comparison with dentigerous cyst and ameloblastoma

    Directory of Open Access Journals (Sweden)

    Seyed Mohammad Razavi

    2015-01-01

    Conclusion: According to the expression of - Bcl-2 in ameloblastoma and KCOT, and no expression of EGFR in KCOT, it can be concluded that the biological activity and growth mechanisms of KCOT are different compared with other cystic lesions. However, the aggressive potential of KCOT is not as severe as that of a neoplasm such as ameloblastoma.

  13. Correlation of cell cycle regulatory proteins (p53 and p16ink4a and bcl-2 oncoprotein with mitotic index and thickness of primary cutaneous malignant melanoma

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    Miloš Kostov

    2010-11-01

    Full Text Available The purpose of the study was to determine the frequency of expression p53 and p16INK4a proteins and bcl2- oncoprotein in malignant skin melanoma and to determine their correlation with the proliferative index and tumor thickness. The study involved 53 patients: 27 (51% male and 26 (49% female. Mitotic index showed a correlation with p53 protein expression, a negative correlation with p16INK4a protein expression. Statistically significant correlations were determined between the Breslow tumor thickness, Clark invasion level and p53 protein expression, as well as Breslow tumor thickness and bcl-2 oncoprotein expression (p<0.05, whereas there was no correlation between the p16INK4a protein expression and melanoma thicknes and Clark invasion level. Overexpression p53 protein and bcl-2 oncoprotein, with the loss p16INK4a protein of expression in the nodular melanoma, confirms a frequent loss of function of these tumor suppressor gene and oncogene, and indicates a vertical tumor growth phase. The loss of tumor suppression function the p53 protein and bcl-2 oncoprotein overexpression in cutaneous melanoma correlates with larger tumor thickness, whereas the overexpression of mutated p53 protein and loss p16INK4a protein of expression indicate a higher proliferative tumour potential. Therefore, these evaluated proteins may be the aggressive biological tumour activity markers.

  14. No dramatic age-related loss of hair cells and spiral ganglion neurons in Bcl-2 over-expression mice or Bax null mice

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    Ohlemiller Kevin K

    2010-07-01

    Full Text Available Abstract Age-related decline of neuronal function is associated with age-related structural changes. In the central nervous system, age-related decline of cognitive performance is thought to be caused by synaptic loss instead of neuronal loss. However, in the cochlea, age-related loss of hair cells and spiral ganglion neurons (SGNs is consistently observed in a variety of species, including humans. Since age-related loss of these cells is a major contributing factor to presbycusis, it is important to study possible molecular mechanisms underlying this age-related cell death. Previous studies suggested that apoptotic pathways were involved in age-related loss of hair cells and SGNs. In the present study, we examined the role of Bcl-2 gene in age-related hearing loss. In one transgenic mouse line over-expressing human Bcl-2, there were no significant differences between transgenic mice and wild type littermate controls in their hearing thresholds during aging. Histological analysis of the hair cells and SGNs showed no significant conservation of these cells in transgenic animals compared to the wild type controls during aging. These data suggest that Bcl-2 overexpression has no significant effect on age-related loss of hair cells and SGNs. We also found no delay of age-related hearing loss in mice lacking Bax gene. These findings suggest that age-related hearing loss is not through an apoptotic pathway involving key members of Bcl-2 family.

  15. JAK2V617F drives Mcl-1 expression and sensitizes hematologic cell lines to dual inhibition of JAK2 and Bcl-xL.

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    Jun Guo

    Full Text Available Constitutive activation of the Janus kinase (JAK/signal transducer and activator of transcription (STAT axis is fundamental to the molecular pathogenesis of a host of hematological disorders, including acute leukemias and myeloproliferative neoplasms (MPN. We demonstrate here that the major JAK2 mutation observed in these diseases (JAK2V617F enforces Mcl-1 transcription via STAT3 signaling. Targeting this lesion with JAK inhibitor I (JAKi-I attenuates STAT3 binding to the Mcl-1 promoter and suppresses Mcl-1 transcript and protein expression. The neutralization of Mcl-1 in JAK2V617F-harboring myelodyssplastic syndrome cell lines sensitizes them to apoptosis induced by the BH3-mimetic and Bcl-xL/Bcl-2 inhibitor, ABT-263. Moreover, simultaneously targeting JAK and Bcl-xL/-2 is synergistic in the presence of the JAK2V617F mutation. These findings suggest that JAK/Bcl-xL/-2 inhibitor combination therapy may have applicability in a range of hematological disorders characterized by activating JAK2 mutations.

  16. Tivantinib (ARQ 197) affects the apoptotic and proliferative machinery downstream of c-MET: role of Mcl-1, Bcl-xl and Cyclin B1.

    Science.gov (United States)

    Lu, Shuai; Török, Helga-Paula; Gallmeier, Eike; Kolligs, Frank T; Rizzani, Antonia; Arena, Sabrina; Göke, Burkhard; Gerbes, Alexander L; De Toni, Enrico N

    2015-09-08

    Tivantinib, a c-MET inhibitor, is investigated as a second-line treatment of HCC. It was shown that c-MET overexpression predicts its efficacy. Therefore, a phase-3 trial of tivantinib has been initiated to recruit "c-MET-high" patients only. However, recent evidence indicates that the anticancer activity of tivantinib is not due to c-MET inhibition, suggesting that c-MET is a predictor of response to this compound rather than its actual target. By assessing the mechanisms underlying the anticancer properties of tivantinib we showed that this agent causes apoptosis and cell cycle arrest by inhibiting the anti-apoptotic molecules Mcl-1 and Bcl-xl, and by increasing Cyclin B1 expression regardless of c-MET status. However, we found that tivantinib might antagonize the antiapoptotic effects of c-MET activation since HGF enhanced the expression of Mcl-1 and Bcl-xl. In summary, we show that the activity of tivantinib is independent of c-MET and describe Mcl-1, Bcl-xl and Cyclin B1 as effectors of its antineoplastic effects in HCC cells. We suggest that the predictive effect of c-MET expression in part reflects the c-MET-driven overexpression of Mcl-1 and Bcl-xl in c-MET-high patients and that these molecules are considered as possible response predictors.

  17. Double-hit BCL2/MYC translocations in a consecutive cohort of patients with large B-cell lymphoma - a single centre's experience

    DEFF Research Database (Denmark)

    Pedersen, Mette Ø; Gang, Anne O; Poulsen, Tim S

    2012-01-01

    Concurrent BCL2 and MYC translocations, so called double hit (DH), are a rare finding in large B-cell lymphoma (LBCL). Based on data from retrospective series, DH has been correlated with aggressive clinical behaviour and poor outcome. We conducted a consecutive study of DH incidence and correlat......Concurrent BCL2 and MYC translocations, so called double hit (DH), are a rare finding in large B-cell lymphoma (LBCL). Based on data from retrospective series, DH has been correlated with aggressive clinical behaviour and poor outcome. We conducted a consecutive study of DH incidence...... and correlation with pathologic and clinical characteristics, including response to Rituximab-containing chemotherapy and survival, in an unselected cohort of patients with LBCL. Translocations involving BCL2 and MYC loci were examined with fluorescent in situ hybridization (FISH) in 157 patients with diffuse...... MYC translocation partner gene. Screening of patients with BCLU and DLBCL of GCB type for DH BCL2/MYC translocation including MYC translocation partner gene may provide important prognostic information....

  18. Protein Kinase C-Mediated Phosphorylation of BCL11B at Serine 2 Negatively Regulates Its Interaction with NuRD Complexes during CD4+ T-Cell Activation.

    Science.gov (United States)

    Dubuissez, Marion; Loison, Ingrid; Paget, Sonia; Vorng, Han; Ait-Yahia, Saliha; Rohr, Olivier; Tsicopoulos, Anne; Leprince, Dominique

    2016-07-01

    The transcription factor BCL11B/CTIP2 is a major regulatory protein implicated in various aspects of development, function and survival of T cells. Mitogen-activated protein kinase (MAPK)-mediated phosphorylation and SUMOylation modulate BCL11B transcriptional activity, switching it from a repressor in naive murine thymocytes to a transcriptional activator in activated thymocytes. Here, we show that BCL11B interacts via its conserved N-terminal MSRRKQ motif with endogenous MTA1 and MTA3 proteins to recruit various NuRD complexes. Furthermore, we demonstrate that protein kinase C (PKC)-mediated phosphorylation of BCL11B Ser2 does not significantly impact BCL11B SUMOylation but negatively regulates NuRD recruitment by dampening the interaction with MTA1 or MTA3 (MTA1/3) and RbAp46 proteins. We detected increased phosphorylation of BCL11B Ser2 upon in vivo activation of transformed and primary human CD4(+) T cells. We show that following activation of CD4(+) T cells, BCL11B still binds to IL-2 and Id2 promoters but activates their transcription by recruiting P300 instead of MTA1. Prolonged stimulation results in the direct transcriptional repression of BCL11B by KLF4. Our results unveil Ser2 phosphorylation as a new BCL11B posttranslational modification linking PKC signaling pathway to T-cell receptor (TCR) activation and define a simple model for the functional switch of BCL11B from a transcriptional repressor to an activator during TCR activation of human CD4(+) T cells. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  19. Prognostic significance of bcl-2 expression in stage III breast cancer patients who had received doxorubicin and cyclophosphamide followed by paclitaxel as adjuvant chemotherapy

    Directory of Open Access Journals (Sweden)

    Kim Dong-Wan

    2007-04-01

    Full Text Available Abstract Background Bcl-2 is positively regulated by hormonal receptor pathways in breast cancer. A study was conducted to assess the prognostic significances of clinico-pathologic variables and of ER, PR, p53, c-erbB2, bcl-2, or Ki-67 as markers of relapse in breast cancer patients who had received the identical adjuvant therapy at a single institution. Methods A cohort of 151 curatively resected stage III breast cancer patients (M:F = 3:148, median age 46 years who had 4 or more positive lymph nodes and received doxorubicin and cyclophosphamide followed by paclitaxel (AC/T as adjuvant chemotherapy was analyzed for clinico-pathologic characteristics including disease-free survival (DFS and overall survival (OS. Patients with positive ER and/or PR expression received 5 years of tamoxifen following AC/T. The protein expressions of biomarkers were assessed immunohistochemically. Results The median follow-up duration was 36 months, and 37 patients (24.5% experienced a recurrence. Univariate analyses indicated that the tumor size (P = 0.038 and the number of involved lymph nodes (P P = 0.013, bcl-2 positivity (P = 0.002 and low p53 expression (P = 0.032 were found to be significantly associated with a prolonged DFS. Furthermore, multivariate analysis identified 10 or more involved lymph nodes (HR 7.366; P P = 0.030, and c-erbB2 over-expression (HR 3.535; P = 0.001 as independent indicators of poorer DFS. In addition, bcl-2 expression was found to be significantly correlated with the expressions of ER and PR, and inversely correlated with the expressions of p53, c-erbB2 and Ki-67. Patients with bcl-2 expression had a significantly longer DFS than those without, even in the ER (+ subgroup. Moreover, OS was significantly affected by ER, bcl-2 and c-erbB2. Conclusion Bcl-2 is an independent prognostic factor of DFS in curatively resected stage III breast cancer patients and appears to be a useful prognostic factor in combination with c-erbB2 and the

  20. Trichonomas vaginalis metalloproteinase induces apoptosis of SiHa cells through disrupting the Mcl-1/Bim and Bcl-xL/Bim complexes.

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    Juan-Hua Quan

    Full Text Available To elucidate the roles of metalloproteinases and the Bcl-2 family of proteins in Trichovaginalis. vaginalis-induced apoptosis in human cervical cancer cells (SiHa cells and vaginal epithelial cells (MS74 cells, SiHa cells and MS74 cells were incubated with live T. vaginalis, T. vaginalis excretory and secretory products (ESP, and T. vaginalis lysates, either with or without the specific metalloproteinase inhibitor 1,10-phenanthroline (1,10-PT, and examined apoptotic events and Bcl-2 signaling. The live T. vaginalis and the T. vaginalis ESP induced the release of cytochrome c into the cytosol, the activation of caspase-3 and caspase-9, and the cleavage of PARP. Additionally, the live T. vaginalis, but not the T. vaginalis lysate, induced the cleavage of the proapoptotic Bim protein. The live T. vaginalis and the T. vaginalis ESP, but not the T. vaginalis lysate, induced the dose-dependent cleavage of the antiapoptotic Bcl-xL and Mcl-1 proteins and decreased the association levels of Bcl-xL/Bim and Mcl-1/Bim complexes. We performed gelatin zymography and casein-hydrolysis assays on the live T. vaginalis and the T. vaginalis ESP to identify the apoptosis-inducing factor. Both the live T. vaginalis and the ESP contained high levels of metalloproteinases, of which activities were significantly inhibited by 1,10-PT treatment. Furthermore, the 1,10-PT blocked the cleavage of Bcl-xL, Mcl-1, PARP, caspase-3, and caspase-9, as well as the release of cytochrome c into the cytosol, and it significantly increased the association levels of the Bcl-xL/Bim and Mcl-1/Bim protein complexes, returning them to normal levels. Our results demonstrate that T. vaginalis induces mitochondria-dependent apoptosis in SiHa cells through the dissociation of Bcl-xL/Bim and Mcl-1/Bim complexes and that the apoptosis is blocked by the metalloproteinase inhibitor 1,10-PT. These results expand our understanding of the role of metalloproteinases in T. vaginalis-induced apoptosis

  1. Trichonomas vaginalis metalloproteinase induces apoptosis of SiHa cells through disrupting the Mcl-1/Bim and Bcl-xL/Bim complexes.

    Science.gov (United States)

    Quan, Juan-Hua; Kang, Byung-Hun; Cha, Guang-Ho; Zhou, Wei; Koh, Young-Bok; Yang, Jung-Bo; Yoo, Heon-Jong; Lee, Min-A; Ryu, Jae-Sook; Noh, Heung-Tae; Kwon, Jaeyul; Lee, Young-Ha

    2014-01-01

    To elucidate the roles of metalloproteinases and the Bcl-2 family of proteins in Trichovaginalis. vaginalis-induced apoptosis in human cervical cancer cells (SiHa cells) and vaginal epithelial cells (MS74 cells), SiHa cells and MS74 cells were incubated with live T. vaginalis, T. vaginalis excretory and secretory products (ESP), and T. vaginalis lysates, either with or without the specific metalloproteinase inhibitor 1,10-phenanthroline (1,10-PT), and examined apoptotic events and Bcl-2 signaling. The live T. vaginalis and the T. vaginalis ESP induced the release of cytochrome c into the cytosol, the activation of caspase-3 and caspase-9, and the cleavage of PARP. Additionally, the live T. vaginalis, but not the T. vaginalis lysate, induced the cleavage of the proapoptotic Bim protein. The live T. vaginalis and the T. vaginalis ESP, but not the T. vaginalis lysate, induced the dose-dependent cleavage of the antiapoptotic Bcl-xL and Mcl-1 proteins and decreased the association levels of Bcl-xL/Bim and Mcl-1/Bim complexes. We performed gelatin zymography and casein-hydrolysis assays on the live T. vaginalis and the T. vaginalis ESP to identify the apoptosis-inducing factor. Both the live T. vaginalis and the ESP contained high levels of metalloproteinases, of which activities were significantly inhibited by 1,10-PT treatment. Furthermore, the 1,10-PT blocked the cleavage of Bcl-xL, Mcl-1, PARP, caspase-3, and caspase-9, as well as the release of cytochrome c into the cytosol, and it significantly increased the association levels of the Bcl-xL/Bim and Mcl-1/Bim protein complexes, returning them to normal levels. Our results demonstrate that T. vaginalis induces mitochondria-dependent apoptosis in SiHa cells through the dissociation of Bcl-xL/Bim and Mcl-1/Bim complexes and that the apoptosis is blocked by the metalloproteinase inhibitor 1,10-PT. These results expand our understanding of the role of metalloproteinases in T. vaginalis-induced apoptosis and the signaling

  2. Delayed apoptosis by neutrophils from COPD patients is associated with altered bak, bcl-xl, and mcl-1 mRNA expression

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    Zhang Jisong

    2012-06-01

    Full Text Available Abstract Background Delayed neutrophil apoptosis may be an important factor in the persistent inflammation associated with chronic obstructive pulmonary disease (COPD. Bcl-2 family proteins are important regulators of neutrophil apoptosis. We determined the mRNA levels of pro-apoptotic Bak and anti-aptototic Bcl-xl and Mcl-1 members of the Bcl-2 family in unstimulated peripheral blood neutrophils from patients with mild to moderate COPD and compared these to neutrophils from healthy controls. Methods Neutrophils were isolated from peripheral blood samples of 47 COPD patients (smokers: N = 24 and 47 healthy controls (smokers: N = 24. Percentages of apoptotic cells were determined at 4, 24, and 36 h for unstimulated neutrophils cultured in vitro. Neutrophil mRNA expression of Bak, Bcl-xl, and Mcl-1 was determined by real-time polymerase chain reaction (PCR. FEV1 (% predicted and FVC were determined by spirometry and correlations between mRNA levels and lung function parameters were determined. Results The percentages of apoptotic cells among unstimulated neutrophils from COPD patients were significantly lower compared to cells from controls after 4, 24, and 36 h in culture; smoking history had only a minimal effect on these differences. Unstimulated neutrophils from COPD patients had significantly lower Bak mRNA expression and higher expressions of Bcl-xl and Mcl-1 mRNA than cells from healthy controls. Again, smoking history had only a minimal effect on these trends. Bak mRNA expression was significantly positively correlated with both % predicted FEV1 and the FEV1/FVC ratio, while Bcl-xl and Mcl-1 mRNA expressions were significantly negatively correlated with %predicted FEV1 and the FEV1/FVC ratio. Conclusions The genes for pro-apoptotic Bak, and anti-apoptotic Bcl-xl and Mcl-1 may be important in regulating the delayed neutrophil apoptosis observed in COPD, which may contribute to COPD pathogenesis. Virtual Slides The virtual slide

  3. Type B and A monoamine oxidase and their inhibitors regulate the gene expression of Bcl-2 and neurotrophic factors in human glioblastoma U118MG cells: different signal pathways for neuroprotection by selegiline and rasagiline.

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    Inaba-Hasegawa, Keiko; Shamoto-Nagai, Masayo; Maruyama, Wakako; Naoi, Makoto

    2017-06-02

    Type B monoamine oxidase (MAO-B) in glial cells has been considered to be associated with neuronal death in Parkinson's disease. MAO-B inhibitors, rasagiline and selegiline [(-)deprenyl], protect neurons in animal and cellular models of neurodegeneration. However, the role of MAO-B itself in the regulation of cell death processing remains elusive, whereas type A MAO (MAO-A) mediates the induction of anti-apoptotic Bcl-2 genes by rasagiline and selegiline. In this paper, the involvement of MAOs in the induction of neuroprotective genes by MAO inhibitors was investigated in human glioblastoma U118MG cells expressing mainly MAO-B. Selegiline significantly increased Mao-B, which was suppressed by Mao-A knockdown with short interfering (si)RNA, whereas rasagiline less markedly increased Mao-B, which was not affected by Mao-A knockdown. Mao-A mRNA was also markedly increased by rasagiline and selegiline, and Mao-B knockdown significantly enhanced the induction by selegiline, but not by rasagiline. Mao-B knockdown also significantly increased mRNA levels of Bcl-2, brain-derived neurotrophic factor (BDNF) and glial cell line-derived neurotrophic factor (GDNF). Selegiline synergistically enhanced the expression of these genes in Mao-B knockdown cells, but Mao-A knockdown suppressed the increase. Rasagiline increased BDNF and GDNF, which Mao-B and Mao-A knockdown inhibited. These results show that MAO-B might function as a repressor and MAO-A as a mediator in the constitutional expression of pro-survival genes, and that MAO-B and MAO-A might regulate different signal pathways for rasagiline and selegiline to induce neuroprotective genes. The novel role of glial MAOs in the regulation of gene expression is discussed.

  4. Drp1 is dispensable for apoptotic cytochrome c release in primed MCF10A and fibroblast cells but affects Bcl-2 antagonist-induced respiratory changes.

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    Clerc, P; Ge, S X; Hwang, H; Waddell, J; Roelofs, B A; Karbowski, M; Sesaki, H; Polster, B M

    2014-04-01

    Dynamin-related protein 1 (Drp1) mediates mitochondrial fission and is thought to promote Bax/Bak-induced cytochrome c release during apoptosis. Conformationally active Bax, Bak and Bax/Bak-activating BH3-only proteins, such as Bim, are restrained by anti-apoptotic Bcl-2 proteins in cells that are 'primed for death'. Inhibition of Bcl-2/Bcl-xL/Bcl-w by the antagonist ABT-737 causes rapid apoptosis of primed cells. Hence, we determined whether Drp1 is required for cytochrome c release, respiratory alterations and apoptosis of cells that are already primed for death. We tested the Drp1 inhibitor mdivi-1 for inhibition of cytochrome c release in MCF10A cells primed by Bcl-2 overexpression. We measured ATP synthesis-dependent, -independent and cytochrome c-limited maximal oxygen consumption rates (OCRs) and cell death of immortalized wild-type (WT) and Drp1 knockout (KO) mouse embryonic fibroblasts (MEFs) treated with ABT-737. Mdivi-1 failed to attenuate ABT-737-induced cytochrome c release. ABT-737 decreased maximal OCR measured in the presence of uncoupler in both WT and Drp1 KO MEF, consistent with respiratory impairment due to release of cytochrome c. However, Drp1 KO MEF were slightly less sensitive to this ABT-737-induced respiratory inhibition compared with WT, and were resistant to an initial ABT-737-induced increase in ATP synthesis-independent O2 consumption. Nevertheless, caspase-dependent cell death was not reduced. Pro-apoptotic Bax was unaltered, whereas Bak was up-regulated in Drp1 KO MEF. The findings indicate that once fibroblast cells are primed for death, Drp1 is not required for apoptosis. However, Drp1 may contribute to ABT-737-induced respiratory changes and the kinetics of cytochrome c release. © 2013 The British Pharmacological Society.

  5. THE PROGNOSTIC SIGNIFICANCE OF P53, BCL2 AND MIB1 EXPRESSIONS RELATED WITH OTHER CLINICOPATHOLOGICAL VARIABLES IN SEROUS OVARIAN CARCINOMAS. A CLINICOPATHOLOGICAL STUDY IN PERITONEAL FLUIDS.

    Science.gov (United States)

    Kalogeraki, Alexandra; Tamiolakis, D; Matalliotaki, Chara; Karvela-Kalogeraki, Iliana; Karvelas-Kalogerakis, M; Segredakis, J; Sinatkas, V; Matalliotakis, I

    2015-01-01

    The first cytological study examining the expression of P53, BCL2 and MIB 1 expressions in correlation with other clinicopathological parameters in ascitic fluids of patients with serous ovarian carcinomas. Fifty women 35-75 years old were diagnosed cytologically and confirmed histologically after operation in the University Hospital of Crete. All carcinomas were serous type and eight(8) of grade I, eighteen (18) of grade II and twenty two (22) of grade III. All carcinomas were staged according to the Figo criteria. Fifteen (15) were of Figo stage III and thirty five (35) were of Figo stage IV. For p53 and bcl-2, staining was evaluated on a semiquantitative scale depending on the number of cells showing positivity. For MIB1, the percentage of positive nuclei was calculated. Main outcome measure(s): The expression of P53, BCL2 and MIB 1 (Ki 67) correlated with tumor grade and Figo stages were estimated by chi-square (χ2). The expression of P53 and MIB1 were found to be statistically significant (p P53 (64%) and MIB1 (72%) and an expression of BCL2 (48%) in ascitic fluid of patients with ovarian carcinoma. A statistically significant correlation between P53 and MIB1 expression correlated with tumor grade and Figo stage (p P53 and MIB1. No significant association was found between P53 and BCL2 expression or MIB1 labeling index. Our data show significant differences in the expression of these markers in ovarian tumors and suggest a possible role for these tumor-associated genes as supplemental tools in prognosis and further definition of the biologic potential of these tumors.

  6. Photobiomodulation on Bax and Bcl-2 Proteins and SIRT1/PGC-1α Axis mRNA Expression Levels of Aging Rat Skeletal Muscle

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    Fang-Hui Li

    2014-01-01

    Full Text Available Objective. This study aimed to analyze the effects of low level laser irradiation (LLLI on Bax and IGF-1 and Bcl-2 protein contents and SIRT1/PGC-1α axis mRNA expression levels to prevent sarcopenia in aged rats. Material and Methods. Twenty female Sprague Dawley rats (18 months old were randomly divided into two groups (n=10 per group: control (CON and LLLI groups. The gallium-aluminum-arsenium (GaAlAs laser irradiation at 810 nm was used in the single point contact mode (3.75 J/cm2; 0.4 cm2; 125 mW/cm2; 30 s. Bax, Bcl-2, and IGF-1 proteins and SIRT1/PGC-1α axis mRNA expression were assessed 24 h after LLLI on gastrocnemius in aged rat. Results. Gastrocnemius muscle weights, gastrocnemius mass/body mass, Bcl-2/BAX ratio, Bcl-2 protein, IGF-1 protein, and the mRNA contents in SIRT1, PGC-1α, NRF1, TMF, and SOD2 were significantly (P<0.05 increased by LLLI compared to CON group without LLLI. However, levels of BAX protein and caspase 3 mRNA were significantly attenuated by LLLI compared to CON group (P<0.05. Conclusion. LLLI at 810 nm inhibits sarcopenia associated with upregulation of Bcl-2/BAX ratio and IGF-1 and SIRT1/PGC-1α axis mRNA expression in aged rats. This indicates that LLLI has potential to decrease progression of myocyte apoptosis in sarcopenic muscles.

  7. Activation of the PI3K-Akt pathway by human T cell leukemia virus type 1 (HTLV-1) oncoprotein Tax increases Bcl3 expression, which is associated with enhanced growth of HTLV-1-infected T cells

    International Nuclear Information System (INIS)

    Saito, Kousuke; Saito, Mineki; Taniura, Naoko; Okuwa, Takako; Ohara, Yoshiro

    2010-01-01

    Bcl3 is a member of the IκB family that regulates genes involved in cell proliferation and apoptosis. Recent reports indicated that Bcl3 is overexpressed in HTLV-1-infected T cells via Tax-mediated transactivation, and acts as a negative regulator of viral transcription. However, the role of Bcl3 in cellular signal transduction and the growth of HTLV-1-infected T cells have not been reported. In this study, we showed that the knockdown of Bcl3 by short hairpin RNA inhibited the growth of HTLV-1-infected T cells. Although phosphatidylinositol-3 kinase (PI3K) inhibitor reduced Bcl3 expression, inactivation of glycogen synthase kinase 3 (GSK3), an effector kinase of the PI3K/Akt signaling pathway, restored Bcl3 expression in Tax-negative but not in Tax-positive T cells. Our results indicate that the overexpression of Bcl3 in HTLV-1-infected T cells is regulated not only by transcriptional but also by post-transcriptional mechanisms, and is involved in overgrowth of HTLV-1-infected T cells.

  8. Apoptosis, proliferation, Bax, Bcl-2 and p53 status prior to and after preoperative radiochemotherapy for locally advanced rectal cancer

    International Nuclear Information System (INIS)

    Tannapfel, Andrea; Nuesslein, Siegfried; Fietkau, Rainer; Katalinic, Alexander; Koeckerling, Ferdinand; Wittekind, Christian

    1998-01-01

    Purpose: To investigate the relationship between apoptotic cell death, proliferative activity, and the expression of apoptosis regulating proteins in rectal cancer prior to and after radiochemotherapy. Materials and Methods: In 32 patients dispositioned to receive preoperative radiochemotherapy for locally advanced rectal carcinoma, pretherapy biopsies and the final resected specimen after radiochemotherapy were available for analyses. Apoptotic cells were identified and quantified using in situ end labeling (ISEL) technique. The expression of the bax protein was assessed immunohistochemically. Additionally, double immunostaining was performed for apoptotic cells and bax expression. The proliferative activity was determined by immunohistochemical assessment of the Ki67 (MIB-1) and the proliferating cell nuclear antigen (PCNA). p53- and bcl-2 expression was analyzed immunohistochemically. A clinical-to-pathologic downstaging after radiochemotherapy was achieved in 25 of 32 patients (78%). During follow-up, tumor recurrence was observed in six cases. In one case, no residual tumor was detected after radiochemotherapy. Results: After radiochemotherapy, the apoptotic index increased significantly in almost every case examined. In contrast, the proliferative activity was significantly decreased in resected specimens as compared to biopsies. Bax immunostaining was detected in 12/31 (39%) biopsies and in 26/31 (84%) resected specimens. In the resected specimen, significantly more apoptotic cells that were bax-positive were found than in biopsies. Bcl-2 immunostaining occurred in 15/31 biopsies and 12/31 resected specimens, respectively. Tumors that were immunohistochemically negative for p53 (20/31 [65%]) generally exhibited a higher apoptotic index and a high expression level of bax than p53-positive tumors (11/31 [35%]). However, we did not find any correlation between the (pre- and post-therapeutic) rate of apoptosis or the level of bax expression and the degree of

  9. Assessing tumor progression factors by somatic gene transfer into a mouse model: Bcl-xL promotes islet tumor cell invasion.

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    Yi-Chieh Nancy Du

    2007-10-01

    Full Text Available Tumors develop through multiple stages, implicating multiple effectors, but the tools to assess how candidate genes contribute to stepwise tumor progression have been limited. We have developed a novel system in which progression of phenotypes in a mouse model of pancreatic islet cell tumorigenesis can be used to measure the effects of genes introduced by cell-type-specific infection with retroviral vectors. In this system, bitransgenic mice, in which the rat insulin promoter (RIP drives expression of both the SV40 T antigen (RIP-Tag and the receptor for subgroup A avian leukosis virus (RIP-tva, are infected with avian viral vectors carrying cDNAs encoding candidate progression factors. Like RIP-Tag mice, RIP-Tag; RIP-tva bitransgenic mice develop isolated carcinomas by approximately 14 wk of age, after progression through well-defined stages that are similar to aspects of human tumor progression, including hyperplasia, angiogenesis, adenoma, and invasive carcinoma. When avian retroviral vectors carrying a green fluorescent protein marker were introduced into RIP-Tag; RIP-tva mice by intra-cardiac injection at the hyperplastic or early dysplastic stage of tumorigenesis, approximately 20% of the TVA-positive cells were infected and expressed green fluorescent proteins as measured by flow cytometry. Similar infection with vectors carrying cDNA encoding either of two progression factors, a dominant-negative version of cadherin 1 (dnE-cad or Bcl-xL, accelerated the formation of islet tumors with invasive properties and pancreatic lymph node metastasis. To begin studying the mechanism by which Bcl-xL, an anti-apoptotic protein, promotes invasion and metastasis, RIP-Tag; RIP-tva pancreatic islet tumor cells were infected in vitro with RCASBP-Bcl-xL. Although no changes were observed in rates of proliferation or apoptosis, Bcl-xL altered cell morphology, remodeled the actin cytoskeleton, and down-regulated cadherin 1; it also induced cell migration and

  10. Structural and functional similarity between the bacterial type III secretion system needle protein PrgI and the eukaryotic apoptosis Bcl-2 proteins.

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    Matthew D Shortridge

    2009-10-01

    Full Text Available Functional similarity is challenging to identify when global sequence and structure similarity is low. Active-sites or functionally relevant regions are evolutionarily more stable relative to the remainder of a protein structure and provide an alternative means to identify potential functional similarity between proteins. We recently developed the FAST-NMR methodology to discover biochemical functions or functional hypotheses of proteins of unknown function by experimentally identifying ligand binding sites. FAST-NMR utilizes our CPASS software and database to assign a function based on a similarity in the structure and sequence of ligand binding sites between proteins of known and unknown function.The PrgI protein from Salmonella typhimurium forms the needle complex in the type III secretion system (T3SS. A FAST-NMR screen identified a similarity between the ligand binding sites of PrgI and the Bcl-2 apoptosis protein Bcl-xL. These ligand binding sites correlate with known protein-protein binding interfaces required for oligomerization. Both proteins form membrane pores through this oligomerization to release effector proteins to stimulate cell death. Structural analysis indicates an overlap between the PrgI structure and the pore forming motif of Bcl-xL. A sequence alignment indicates conservation between the PrgI and Bcl-xL ligand binding sites and pore formation regions. This active-site similarity was then used to verify that chelerythrine, a known Bcl-xL inhibitor, also binds PrgI.A structural and functional relationship between the bacterial T3SS and eukaryotic apoptosis was identified using our FAST-NMR ligand affinity screen in combination with a bioinformatic analysis based on our CPASS program. A similarity between PrgI and Bcl-xL is not readily apparent using traditional global sequence and structure analysis, but was only identified because of conservation in ligand binding sites. These results demonstrate the unique opportunity

  11. Normal Hematopoietic Progenitor Subsets Have Distinct Reactive Oxygen Species, BCL2 and Cell-Cycle Profiles That Are Decoupled from Maturation in Acute Myeloid Leukemia.

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    Naeem Khan

    Full Text Available In acute myeloid leukemia (AML quiescence and low oxidative state, linked to BCL2 mitochondrial regulation, endow leukemic stem cells (LSC with treatment-resistance. LSC in CD34+ and more mature CD34- AML have heterogeneous immunophenotypes overlapping with normal stem/progenitor cells (SPC but may be differentiated by functional markers. We therefore investigated the oxidative/reactive oxygen species (ROS profile, its relationship with cell-cycle/BCL2 for normal SPC, and whether altered in AML and myelodysplasia (MDS. In control BM (n = 24, ROS levels were highest in granulocyte-macrophage progenitors (GMP and CD34- myeloid precursors but megakaryocyte-erythroid progenitors had equivalent levels to CD34+CD38low immature-SPC although they were ki67high. BCL2 upregulation was specific to GMPs. This profile was also observed for CD34+SPC in MDS-without-excess-blasts (MDS-noEB, n = 12. Erythroid CD34- precursors were, however, abnormally ROS-high in MDS-noEB, potentially linking oxidative stress to cell loss. In pre-treatment AML (n = 93 and MDS-with-excess-blasts (MDS-RAEB (n = 14, immunophenotypic mature-SPC had similar ROS levels to co-existing immature-SPC. However ROS levels varied between AMLs; Flt3ITD+/NPM1wild-type CD34+SPC had higher ROS than NPM1mutated CD34+ or CD34- SPC. An aberrant ki67lowBCL2high immunophenotype was observed in CD34+AML (most prominent in Flt3ITD AMLs but also in CD34- AMLs and MDS-RAEB, suggesting a shared redox/pro-survival adaptation. Some patients had BCL2 overexpression in CD34+ ROS-high as well as ROS-low fractions which may be indicative of poor early response to standard chemotherapy. Thus normal SPC subsets have distinct ROS, cell-cycle, BCL2 profiles that in AML /MDS-RAEB are decoupled from maturation. The combined profile of these functional properties in AML subpopulations may be relevant to differential treatment resistance.

  12. Canonical Bcl-2 motifs of the Na+/K+ pump revealed by the BH3 mimetic chelerythrine: early signal transducers of apoptosis?

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    Lauf, Peter K; Heiny, Judith; Meller, Jarek; Lepera, Michael A; Koikov, Leonid; Alter, Gerald M; Brown, Thomas L; Adragna, Norma C

    2013-01-01

    Chelerythrine [CET], a protein kinase C [PKC] inhibitor, is a prop-apoptotic BH3-mimetic binding to BH1-like motifs of Bcl-2 proteins. CET action was examined on PKC phosphorylation-dependent membrane transporters (Na+/K+ pump/ATPase [NKP, NKA], Na+-K+-2Cl+ [NKCC] and K+-Cl- [KCC] cotransporters, and channel-supported K+ loss) in human lens epithelial cells [LECs]. K+ loss and K+ uptake, using Rb+ as congener, were measured by atomic absorption/emission spectrophotometry with NKP and NKCC inhibitors, and Cl- replacement by NO3ˉ to determine KCC. 3H-Ouabain binding was performed on a pig renal NKA in the presence and absence of CET. Bcl-2 protein and NKA sequences were aligned and motifs identified and mapped using PROSITE in conjunction with BLAST alignments and analysis of conservation and structural similarity based on prediction of secondary and crystal structures. CET inhibited NKP and NKCC by >90% (IC50 values ~35 and ~15 μM, respectively) without significant KCC activity change, and stimulated K+ loss by ~35% at 10-30 μM. Neither ATP levels nor phosphorylation of the NKA α1 subunit changed. 3H-ouabain was displaced from pig renal NKA only at 100 fold higher CET concentrations than the ligand. Sequence alignments of NKA with BH1- and BH3-like motifs containing pro-survival Bcl-2 and BclXl proteins showed more than one BH1-like motif within NKA for interaction with CET or with BH3 motifs. One NKA BH1-like motif (ARAAEILARDGPN) was also found in all P-type ATPases. Also, NKA possessed a second motif similar to that near the BH3 region of Bcl-2. Findings support the hypothesis that CET inhibits NKP by binding to BH1-like motifs and disrupting the α1 subunit catalytic activity through conformational changes. By interacting with Bcl-2 proteins through their complementary BH1- or BH3-like-motifs, NKP proteins may be sensors of normal and pathological cell functions, becoming important yet unrecognized signal transducers in the initial phases of apoptosis. CET

  13. Canonical Bcl-2 Motifs of the Na+/K+ Pump Revealed by the BH3 Mimetic Chelerythrine: Early Signal Transducers of Apoptosis?

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    Peter K. Lauf

    2013-02-01

    Full Text Available Background/Aims: Chelerythrine [CET], a protein kinase C [PKC] inhibitor, is a prop-apoptotic BH3-mimetic binding to BH1-like motifs of Bcl-2 proteins. CET action was examined on PKC phosphorylation-dependent membrane transporters (Na+/K+ pump/ATPase [NKP, NKA], Na+-K+-2Cl+ [NKCC] and K+-Cl- [KCC] cotransporters, and channel-supported K+ loss in human lens epithelial cells [LECs]. Methods: K+ loss and K+ uptake, using Rb+ as congener, were measured by atomic absorption/emission spectrophotometry with NKP and NKCC inhibitors, and Cl- replacement by NO3ˉ to determine KCC. 3H-Ouabain binding was performed on a pig renal NKA in the presence and absence of CET. Bcl-2 protein and NKA sequences were aligned and motifs identified and mapped using PROSITE in conjunction with BLAST alignments and analysis of conservation and structural similarity based on prediction of secondary and crystal structures. Results: CET inhibited NKP and NKCC by >90% (IC50 values ∼35 and ∼15 µM, respectively without significant KCC activity change, and stimulated K+ loss by ∼35% at 10-30 µM. Neither ATP levels nor phosphorylation of the NKA α1 subunit changed. 3H-ouabain was displaced from pig renal NKA only at 100 fold higher CET concentrations than the ligand. Sequence alignments of NKA with BH1- and BH3-like motifs containing pro-survival Bcl-2 and BclXl proteins showed more than one BH1-like motif within NKA for interaction with CET or with BH3 motifs. One NKA BH1-like motif (ARAAEILARDGPN was also found in all P-type ATPases. Also, NKA possessed a second motif similar to that near the BH3 region of Bcl-2. Conclusion: Findings support the hypothesis that CET inhibits NKP by binding to BH1-like motifs and disrupting the α1 subunit catalytic activity through conformational changes. By interacting with Bcl-2 proteins through their complementary BH1- or BH3-like-motifs, NKP proteins may be sensors of normal and pathological cell functions, becoming important yet

  14. P53 and MITF/Bcl-2 identified as key pathways in the acquired resistance of NRAS-mutant melanoma to MEK inhibition.

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    Najem, Ahmad; Krayem, Mohammad; Salès, François; Hussein, Nader; Badran, Bassam; Robert, Caroline; Awada, Ahmad; Journe, Fabrice; Ghanem, Ghanem E

    2017-09-01

    Activating mutations in Neuroblastoma RAS viral oncogene homolog (NRAS) are found in 15-30% of melanomas and are associated with a poor prognosis. Although MAP kinase kinase (MEK) inhibitors used as single agents showed a limited clinical benefit in patients with NRAS-mutant melanoma due to their rather cytostatic effect and high toxicity, their combination with other inhibitors of pathways known to cooperate with MEK inhibition may maximise their antitumour activity. Similarly, in a context where p53 is largely inactivated in melanoma, hyperexpression of Microphthalmia associated transcription factor (MITF) and its downstream anti-apoptotic targets may be the cause of the restraint cytotoxic effects of MEK inhibitors. Indeed, drug combinations targeting both mutant BRAF and MITF or one of its important targets Bcl-2 were effective in mutant BRAF melanoma but had no effect on acquired resistance. Therefore, we aimed to further investigate the downstream MITF targets that can explain this anti-apoptotic effect and to evaluate in parallel the effect of p53 reactivation on the promotion of apoptosis under MEK inhibition in a panel of Q61 NRAS-mutant melanoma cells. First, we showed that MEK inhibition (pimasertib) led to a significant inhibition of cell proliferation but with a limited effect on apoptosis that could be explained by the systematic MITF upregulation. Mimicking the MITF effect via cyclic adenosine monophosphate activation conferred resistance to MEK inhibition and upregulated Bcl-2 expression. In addition, acquired resistance to MEK inhibition was associated with a strong activation of the anti-apoptotic signalling MITF/Bcl-2. More importantly, selective Bcl-2 inhibition by ABT-199 or Bcl-2 knockout using CRISPR/Cas9 system annihilated the acquired resistance and restored the sensitivity of NRAS-mutant melanoma cells to MEK inhibition. Strikingly and similarly, direct p53 reactivation (PRIMA-1 Met , APR-246) also broke resistance and synergised with MEK

  15. Clinical significance of proliferation, apoptosis and senescence of nasopharyngeal cells by the simultaneously blocking EGF, IGF-1 receptors and Bcl-xl genes

    Energy Technology Data Exchange (ETDEWEB)

    Dai, Guodong [Anatomy and Embryology, Wuhan University School of Medicine, Wuhan, Hubei 430071 (China); Peng, Tao; Zhou, Xuhong [Department of Otolaryngology-Head and Neck Surgery, Zhongnan Hospital of Wuhan University, Wuhan 430071 (China); Zhu, Jun; Kong, Zhihua; Ma, Li; Xiong, Zhi [Anatomy and Embryology, Wuhan University School of Medicine, Wuhan, Hubei 430071 (China); Yuan, Yulin, E-mail: yuanyulin19620120@126.com [Anatomy and Embryology, Wuhan University School of Medicine, Wuhan, Hubei 430071 (China)

    2013-11-01

    Highlight: •Construction of shRNA segments expression vectors is valid by the investigation of RT-PCR for IGF1R, EGFR and Bcl-xl mRNA and protein expression. •Studies have suggested that the vectors in blocking these genes of the growth factor receptors and anti- apoptosis is capable of breaking the balance of tumor growth so that tumor trend apoptosis and senescence. •Simultaneously blocking multiple genes that are abnormally expressed may be more effective in treating cancer cells than silencing a single gene. -- Abstract: Background: In previous work, we constructed short hairpin RNA (shRNA) expression plasmids that targeted human EGF and IGF-1 receptors messenger RNA, respectively, and demonstrated that these vectors could induce apoptosis of human nasopharyngeal cell lines (CNE2) and inhibit ligand-induced pAkt and pErk activation. Method: We have constructed multiple shRNA expression vectors of targeting EGFR, IGF1R and Bcl-xl, which were transfected to the CNE2 cells. The mRNA expression was assessed by RT-PCR. The growth of the cells, cell cycle progression, apoptosis of the cells, senescent tumor cells and the proteins of EGFR, IGF1R and Bcl-xl were analyzed by MTT, flow cytometry, cytochemical therapy or Western blot. Results: In group of simultaneously blocking EGFR, IGF1R and Bcl-xl genes, the mRNA of EGFR, IGF1R and Bcl-xl expression was decreased by (66.66 ± 3.42)%, (73.97 ± 2.83)% and (64.79 ± 2.83)%, and the protein expressions was diminished to (67.69 ± 4.02)%, (74.32 ± 2.30)%, and (60.00 ± 3.34)%, respectively. Meanwhile, the cell apoptosis increased by 65.32 ± 0.18%, 65.16 ± 0.25% and 55.47 ± 0.45%, and senescent cells increased by 1.42 ± 0.15%, 2.26 ± 0.15% and 3.22 ± 0.15% in the second, third and fourth day cultures, respectively. Conclusions: Simultaneously blocking EGFR, IGF1R and Bcl-xl genes is capable of altering the balance between proliferating versus apoptotic and senescent cells in the favor of both of apoptosis and

  16. Prevalence and cardiometabolic associations of the glucocorticoid receptor gene polymorphisms N363S and BclI in obese and non-obese black and white Mississippians.

    Science.gov (United States)

    Melcescu, Eugen; Griswold, Michael; Xiang, Lianbin; Belk, Sheila; Montgomery, Denise; Bray, Marilyn; Del Ben, Kevin S; Uwaifo, Gabriel I; Marshall, Gailen D; Koch, Christian A

    2012-01-01

    Polymorphisms (SNP) in the glucocorticoid receptor (GR) gene can alter sensitivity to glucocorticoids. Previous studies of the N363S and BclI SNP in the GR gene have shown a metabolic syndrome phenotype in mostly non-African populations. The obesity phenotype of African Americans (AA) seems to be more severe than that of Caucasians. We aimed to assess the prevalence of N363S and BclI in obese and non-obese Caucasian (n=26) and African (n=23) Mississippians (age: 23-63 years) to investigate associations with body composition (body mass index/BMI, waist-to-hip ratio), metabolic parameters (salivary cortisol, fasting glucose and insulin, hemoglobin A1C, fructosamine, HOMA-IR index), and psychological stress perception (blood pressure/BP, perceived stress scale/PSS). All subjects were homozygous for wildtype N363N. BclI polymorphism genotype frequencies among the 23 AA were: homozygous CC (57%), GG (4%), and heterozygous CG (39%), and among the 26 white women: homozygous CC (35%), GG (19%), and heterozygous CG (46%). Linear and logistic regression analyses including a parsimonious model identified BMI as a statistically significant parameter between the two ethnic groups (BMI was 3.13 kg/m2 higher in AA). Within the AA group, BMI, waist-to-hip ratio, log (HOMA-IR), PSS scores, BP, and hyperlipidemia showed no statistically significant relationships for the BclI polymorphism. PSS scores were 15.2 for AA vs. 14.7 for white women (normal mean: 14.7 vs. 12.8). Black Mississippians have a higher BMI than whites, which may be related to the presence of the BclI polymorphism and increased glucocorticoid sensitivity. Although more blacks (52%) than whites (38%) had elevated BP, PSS scores in both groups suggest that a high BMI is not regarded as abnormal or stressful. This might negatively impact behavior change regarding lifestyle modifications with increased physical activity and healthier food choices. Larger studies, particularly in African populations, are needed to

  17. Breastfeeding and Immunohistochemical Expression of ki-67, p53 and BCL2 in Infiltrating Lobular Breast Carcinoma.

    Directory of Open Access Journals (Sweden)

    Angel Gonzalez-Sistal

    Full Text Available Invasive lobular breast carcinoma is the second most common type of breast cancer after invasive ductal carcinoma. According to the American Cancer Society, more than 180,000 women in the United States find out they have invasive breast cancer each year. Personal history of breast cancer and certain changes in the breast are correlated with an increased breast cancer risk. The aim of this work was to analyze breastfeeding in patients with infiltrating lobular breast carcinoma, in relation with: 1 clinicopathological parameters, 2 hormonal receptors and 3 tissue-based tumor markers.The study included 80 women with ILC, 46 of which had breastfeed their children. Analyzed parameters were: age, tumor size, axillary lymph node (N, distant metastasis (M, histological grade (HG, estrogen receptor (ER, progesterone receptor (PR, androgen receptor (AR, Ki-67, p53 and BCL2.ILC of non-lactating women showed a larger (p = 0.009, lymph node involvement (p = 0.051 and distant metastasis (p = 0.060. They were also more proliferative tumors measured by Ki-67 (p = 0.053. Breastfeeding history did not influence the subsequent behavior of the tumor regardless of histological subtype.Lactation seems to influence the biological characteristics of ILC defining a subgroup with more tumor size, axillary lymph node involvement, distant metastasis and higher proliferation measured by ki-67 expression.

  18. Homologous recombination in mammalian cells: effect of p53 and Bcl-2 proteins, replication inhibition and ionizing radiations

    International Nuclear Information System (INIS)

    Saintigny, Yannick

    1999-01-01

    The control of cell cycle, associated with the mechanisms of replication, DNA repair/recombination allows the cells to maintain their genetic integrity. The p53 protein ensures the control of G1/S transition. Its inactivation would allow to initial replication on damaged matrix and lead to the block of replication forks followed by DNA strand breaks, good substrates for recombination. This work shows that the expression of mutant p53 protein stimulates both spontaneous and radio-induced homologous recombination, independently of the control of cell cycle. Moreover, the use of a set of replication inhibitors show that inhibition of the replication elongation stimulates recombination more strongly than the initiation inhibition. Replication arrest by these inhibitors also significantly increases the number of DNA strand breaks. These results highlighted a point of action of p53 protein on the ultimate stages of the homologous recombination mechanism. Lastly, the expression of Bcl-2 protein inhibits apoptosis and increases survival, but specifically inhibits conservative recombination, after radiation as well as in absence of apoptotic stress. The extinction of this mechanism of DNA repair is associated with an increase of mutagenesis. Taken together, these results allow ta consider the maintenance of the genetic stability as a cellular network involving different pathways. A multiple stages model for tumoral progression can be deduced. (author) [fr

  19. Relationship between bcl-2, bax, beclin-1, and cathepsin-D proteins during postovulatory follicular regression in fish ovary.

    Science.gov (United States)

    Morais, Roberto D V S; Thomé, Ralph G; Santos, Hélio B; Bazzoli, Nilo; Rizzo, Elizete

    2016-04-01

    In fish ovaries, postovulatory follicles (POFs) are key biomarkers of breeding and provide an interesting model for studying the relationship between autophagy and apoptosis. In this study, we investigated the immunohistochemical expression of autophagic and apoptotic proteins to improve the knowledge on the mechanisms regulating ovarian remodeling after spawning. Females from three neotropical fish species kept in captivity were submitted to hormonal induction. After ova stripping, ovarian sections were sampled daily until 5 days postspawning (dps). Similar events of POF regression were detected by histology, terminal transferase-mediated dUTP nick-end labeling (TUNEL), and electron microscopy in the three species: follicular cells hypertrophy, progressive disintegration of the basement membrane, gradual closing of the follicular lumen, theca thickening, and formation of large autophagic vacuoles preceding apoptosis of the follicular cells. Autophagic and apoptotic proteins were assessed by immunohistochemistry. Morphometric analysis of the immunolabeling revealed a more intense reaction for bcl-2 and beclin-1 (BECN1) in POFs at 0 to 1 dps and for bax at 2 to 3 dps (P family, BECN1, and cathepsin-D can be involved in the regulation of ovarian remodeling in teleost fish. Copyright © 2016 Elsevier Inc. All rights reserved.

  20. Bcl-2 and CD10 expression in the differential diagnosis of trichoblastoma, basal cell carcinoma, and basal cell carcinoma with follicular differentiation.

    Science.gov (United States)

    Córdoba, Alicia; Guerrero, David; Larrinaga, Begoña; Iglesias, Maria Eugenia; Arrechea, Maria Asunción; Yanguas, Juan Ignacio

    2009-07-01

    Both trichoblastoma and basal cell carcinoma (BCC) of the skin are characterized morphologically by the proliferation of basaloid cells; however, BCCs are clinically associated with a more aggressive behavior. An accurate diagnosis of these lesions is essential for effective, timely treatment and appropriate therapeutic decisions. This study includes 40 lesions. Bcl-2 and CD10 immunohistochemistry were performed in all cases and the patterns of expression were analyzed. Bcl-2 is useful for the detection of BCC with diffuse expression in nests of basaloid cells, but cannot distinguish between BCC with follicular differentiation and trichoblastoma, as both lesions show the same pattern with positive and negative areas. Conversely, CD10 expression can distinguish between trichoblastomas with peritumoral stromal staining and BCCs with epithelial staining. If both stromal and epithelial areas are stained, these cases are classified as BCC with follicular differentiation. CD10 is useful for distinguishing between BCC with widespread follicular differentiation and trichoblastomas.

  1. Sequence-specific 1H, 13C, and 15N resonance assignments of Diva (Boo), an apoptosis regulator of the Bcl-2 family.

    Science.gov (United States)

    Sborgi, Lorenzo; de Alba, Eva

    2010-04-01

    Diva, also known as Boo, is a member of the Bcl-2 family that regulates apoptosis by interacting with other Bcl-2 proteins and with the key component of the apoptosome Apaf-1. The function of Diva is puzzling as it apparently can both promote and inhibit apoptosis depending on the cellular context. The structural characterization of Diva will likely help to understand this dual behavior in programmed cell death. To this aim we report here the NMR resonance assignments of residues 1-160 of mouse Diva (lacking the predicted transmembrane domain, which spans residues 161-191). These data are used to obtain information on Diva's secondary structure and provide the basis for further structural studies.

  2. Immunohistological expression of HIF-1α, GLUT-1, Bcl-2 and Ki-67 in consecutive biopsies during chemoradiotherapy in patients with rectal cancer

    DEFF Research Database (Denmark)

    Havelund, Birgitte Mayland; Sørensen, Flemming Brandt; Pløen, John

    2013-01-01

    The aim of this study was to describe the dynamics of HIF-1α, GLUT-1, Bcl-2 and Ki-67 during chemoradiotherapy (CRT) of rectal cancer, and to investigate the fluctuation of these biomarkers in relation to pathological response to CRT. The study included 86 patients with rectal adenocarcinoma...... during CRT, whereas GLUT-1 overall was unchanged. No significant changes of the markers were observed in the interval between CRT and surgery. A significant association was observed between the presence of residual carcinoma after 6 weeks of treatment and pathological response to CRT, but no association...... was seen between the fluctuations of any of the markers and response to CRT. This unique material containing specimens before, after and during CRT for rectal cancer demonstrated biological dynamics in HIF-1α, Bcl-2 and Ki-67, but not GLUT-1, expression during CRT, and a significant association was seen...

  3. MYC translocation partner gene determines survival of patients with large B-cell lymphoma with MYC- or double-hit MYC/BCL2 translocations

    DEFF Research Database (Denmark)

    Pedersen, Mette Ø; Gang, Anne O; Poulsen, Tim S

    2014-01-01

    In large B-cell lymphoma (LBCL) MYC- and MYC/BCL2 double-hit (DH) translocations have been associated with inferior survival. We hypothesised that the negative prognostic impact of MYC translocation was determined by an immunoglobulin MYC translocation partner gene (IG-MYC), as opposed to a non......-immunoglobulin partner gene (nonIG-MYC). In a prospective, unselected cohort of 237 LBCL patients MYC and BCL2 translocations were identified by fluorescent in situ hybridisation (FISH) with split probes. MYC translocation partner gene was identified by IGH/MYC fusion probes and/or kappa/lambda split probes. Clinical...... data were collected from patient files. MYC translocation was identified in 28/225 patients. IG-MYC translocation partner gene was identified in 12/24 patients. DH translocation was identified in 23/228 patients. IG-MYC translocation partner gene was identified in 9/19 DH patients. Neither MYC-nor DH...

  4. An Assay of Bax and Bcl2 Expression in Mice Hippocampus Following Ischemia-Reperfusion Treatment with CoQ10

    Directory of Open Access Journals (Sweden)

    Jalal Hassanshahi

    2013-10-01

    Full Text Available Introduction: Preliminary studies confirmed reduction of cell death following treatment with antioxidants. According to this finding we investigated the relationship between consumption of CoQ10 and expression of bax and bcl2 in hippocampus ischemia that this expression related to cell programmed death.Material and Methods: We studied the protective role of CoQ10 against ischemia-reperfusion. Experimental design includes four groups: intact (N=7, ischemic control (N=7, sham control (N=7 and treatment groups with CoQ10 (N=7. The mice (treatment group treated with CoQ10 as Pre-Treatment for a week. Then, ischemia induced by common carotid artery ligation and following the reduction in inflammation (a week the treatment group post-treated with CoQ10 for a week. Nissl staining applied to counting necrotic cells of hippocampus and the western blotting performed to measurement the bax and bcl2 expression. Tunnel kit was used to quantify apoptotic cell death while to short term memory scale, we apply Y-maze.Results: Cell death was significantly lower when mice treated with CoQ10. Bax expression was significantly high in ischemic group but in treatment group was less and reversely the bcl2 expression in ischemic group was lower than treatment and vehicle groups. The memory test results were consistent with cell death results. Conclusion: Ischemia for 15 minutes induced cell death in hippocampus with more potent effect on CA1. CoQ10 intake significantly reduced cell death and decreased memory loss. with prevent of expression of bax and increase in expression of bcl2.

  5. Inhibition of Rac1 ameliorates neuronal oxidative stress damage via reducing Bcl-2/Rac1 complex formation in mitochondria through PI3K/Akt/mTOR pathway.

    Science.gov (United States)

    Pan, Yundan; Wang, Na; Xia, Pingping; Wang, E; Guo, Qulian; Ye, Zhi

    2018-02-01

    Although the neuroprotective effects of Rac1 inhibition have been reported in various cerebral ischemic models, the molecular mechanisms of action have not yet been fully elucidated. In this study, we investigated whether the inhibition of Rac1 provided neuroprotection in a diabetic rat model of focal cerebral ischemia and hyperglycemia-exposed PC-12 cells. Intracerebroventricular administration of lentivirus expressing the Rac1 small hairpin RNA (shRNA) and specific Rac1 inhibitor NSC23766 not only decreased the infarct volumes and improved neurologic deficits with a correlated significant activation of mitochondrial DNA specific proteins, such as OGG1 and POLG, but also elevated Bcl-2 S70 phosphorylation in mitochondria. Furthermore, the levels of p-PI3K, p-Akt and p-mTOR increased, while 8-OHdG, ROS production and Bcl-2/Rac1 complex formation in mitochondria reduced in both Rac1-shRNA- and NSC23766-treated rats. Moreover, to confirm our in vivo observations, inhibition of Rac1 activity by NSC23766 suppressed the interactions between Bcl-2 and Rac1 in the mitochondria of PC-12 cells cultured in high glucose conditions and protected PC-12 cells from high glucose-induced neurotoxicity. More importantly, these beneficial effects of Rac1 inhibition were abolished by PI3K inhibitor LY294002. In contrast to NSC23766 treatment, LY294002 had little effect on the decrement of p-PTEN level. Taken together, these findings revealed novel neuroprotective roles of Rac1 inhibition against cerebral ischemic reperfusion injury in vivo and high glucose-induced neurotoxicity in PC-12 cells in vitro, by reducing Bcl-2/Rac1 complex formation in mitochondria through the activation of PI3K/Akt/mTOR survival pathway. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. Lycopene counteracts the hepatic response to 7,12-dimethylbenz[a]anthracene by altering the expression of Bax, Bcl-2, caspases, and oxidative stress biomarkers.

    Science.gov (United States)

    Agca, Can Ali; Tuzcu, Mehmet; Gencoglu, Hasan; Akdemir, Fatih; Ali, Shakir; Sahin, Kazim; Kucuk, Omer

    2012-12-01

    Lycopene is a carotenoid found in tomato, watermelon, pink grapefruit, and guava in high concentration. Dietary intake of lycopene has been proposed to inversely correlate with the risk of cancer. It has also been reported to provide protection against cellular damage caused by reactive oxygen species, which makes it worthwhile to study the effect of lycopene on liver damage in rat model. In this study, we report the effect of lycopene on 7,12-dimethylbenz[a]-anthracene (DMBA)-induced expression of Bax, Bcl-2, caspases, and oxidative stres biomarkers in the liver. Lycopene was administered orally at 20 mg/kg body weight for 20 weeks followed by the intraperitoneal injection of DMBA (50 mg/kg body weight) on day 1 and day 30 of the experiment. Control rats received vehicle (olive oil) or DMBA alone. Rats were sacrificed after completion of the treatment. We observed that the levels of Bax, caspase-3, and caspase-9 decreased to 44, 67, and 43%, respectively, and Bcl-2 increased by 80% in DMBA-treated rats. Lycopene reversed the changes in the respective groups, and decreased the level of Bcl-2 to 25%, while increasing the Bax to 42% when compared to DMBA control. Lycopene increased the expression of caspase-3 (82.09%) and caspase-9 (58.96%), and attenuated the level of hepatic malondialdehyde (41%) and 8-isoprostane (40%) when compared to the respective controls. Glutathione (GSH) decreased significantly in DMBA group (15.89%), but reached the normal level in lycopene-treated animals. Hepatic lycopene concentration in treated rats was 8.2 nmol/g tissue. The study reports that lycopene counteracts the hepatic response to DMBA by altering the expression of Bax, Bcl-2, caspases, and oxidative stress biomarkers in animal model.

  7. Metformin combined with aspirin significantly inhibit pancreatic cancer cell growth in vitro and in vivo by suppressing anti-apoptotic proteins Mcl-1 and Bcl-2.

    Science.gov (United States)

    Yue, Wen; Zheng, Xi; Lin, Yong; Yang, Chung S; Xu, Qing; Carpizo, Darren; Huang, Huarong; DiPaola, Robert S; Tan, Xiang-Lin

    2015-08-28

    Metformin and aspirin have been studied extensively as cancer preventive or therapeutic agents. However, the effects of their combination on pancreatic cancer cells have not been investigated. Herein, we evaluated the effects of metformin and aspirin, alone or in combination, on cell viability, migration, and apoptosis as well as the molecular changes in mTOR, STAT3 and apoptotic signaling pathways in PANC-1 and BxPC3 cells. Metformin and aspirin, at relatively low concentrations, demonstrated synergistically inhibitory effects on cell viability. Compared to the untreated control or individual drug, the combination of metformin and aspirin significantly inhibited cell migration and colony formation of both PANC-1 and BxPC-3 cells. Metformin combined with aspirin significantly inhibited the phosphorylation of mTOR and STAT3, and induced apoptosis as measured by caspase-3 and PARP cleavage. Remarkably, metformin combined with aspirin significantly downregulated the anti-apoptotic proteins Mcl-1 and Bcl-2, and upregulated the pro-apoptotic proteins Bim and Puma, as well as interrupted their interactions. The downregulation of Mcl-1 and Bcl-2 was independent of AMPK or STAT3 pathway but partially through mTOR signaling and proteasome degradation. In a PANC-1 xenograft mouse model, we demonstrated that the combination of metformin and aspirin significantly inhibited tumor growth and downregulated the protein expression of Mcl-1 and Bcl-2 in tumors. Taken together, the combination of metformin and aspirin significantly inhibited pancreatic cancer cell growth in vitro and in vivo by regulating the pro- and anti-apoptotic Bcl-2 family members, supporting the continued investigation of this two drug combination as chemopreventive or chemotherapeutic agents for pancreatic cancer.

  8. Cotton Leaf Curl Multan Betasatellite DNA as a Tool to Deliver and Express the Human B-Cell Lymphoma 2 (Bcl-2) Gene in Plants.

    Science.gov (United States)

    Kharazmi, Sara; Ataie Kachoie, Elham; Behjatnia, Seyed Ali Akbar

    2016-05-01

    The betasatellite DNA associated with Cotton leaf curl Multan virus (CLCuMB) contains a single complementary-sense ORF, βC1, which is a pathogenicity determinant. CLCuMB was able to replicate in plants in the presence of diverse helper geminiviruses, including Tomato leaf curl virus-Australia (TLCV-Au), Iranian isolate of Tomato yellow leaf curl virus (TYLCV-[Ab]), and Beet curly top virus (BCTV-Svr), and can be used as a plant gene delivery vector. To test the hypothesis that CLCuMB has the potential to act as an animal gene delivery vector, a specific insertion construct was produced by the introduction of a human B-cell lymphoma 2 (Bcl-2) cDNA into a mutant DNA of CLCuMB in which the βC1 was deleted (β∆C1). The recombinant βΔC1-Bcl-2 construct was successfully replicated in tomato and tobacco plants in the presence of TLCV-Au, BCTV-Svr and TYLCV-[Ab]. Real-time PCR and Western blot analyses of plants containing the replicative forms of recombinant βΔC1-Bcl-2 DNA showed that Bcl-2 gene was expressed in an acceptable level in these plants, indicating that β∆C1 can be used as a tool to deliver and express animal genes in plants. This CLCuMB-based system, having its own promoter activity, offers the possibility of production of animal recombinant proteins in plants.

  9. Comparative analysis between RQ-PCR and digital droplet PCR of BCL2/IGH gene rearrangement in the peripheral blood and bone marrow of early stage follicular lymphoma.

    Science.gov (United States)

    Cavalli, Marzia; De Novi, Lucia Anna; Della Starza, Irene; Cappelli, Luca Vincenzo; Nunes, Vittorio; Pulsoni, Alessandro; Del Giudice, Ilaria; Guarini, Anna; Foà, Robin

    2017-05-01

    BCL2/IGH rearrangements were analysed by polymerase chain reaction (PCR) at diagnosis in paired peripheral blood (PB) and bone marrow (BM) samples from 67 patients with stage I/II follicular lymphoma (FL). Real time quantitative PCR (RQ-PCR) and digital droplet PCR (ddPCR) were performed in cases with a major breakpoint region (MBR+) at diagnosis and after localized radiotherapy and rituximab administration in order to investigate the applicability of ddPCR. The overall ddPCR/RQ-PCR concordance was 81·9% (113/138 samples) and 97·5% in the 40/138 with quantifiable disease (RQ-PCR≥10 -5 ). At baseline, ddPCR allowed the recovery of a MBR+ marker in 8/18 (44·4%) samples that resulted MBR-negative/minor cluster region-negative/minor BCL2-negative by qualitative PCR. Moreover, the tumour burden at diagnosis significantly predicted progression-free survival (PSF) only when quantified by ddPCR. Paired PB and BM samples analysis demonstrated a high concordance in the detection of BCL2/IGH+ cells by qualitative and quantitative methods; in particular, 40/62 samples were positive by ddPCR (25 PB+/BM+; 9 PB+/BM-; 6 PB-/BM+), with 34/40 (85%) identified by the study of PB only. In conclusion, in localized FL, ddPCR is a promising tool for monitoring minimal residual disease (MRD) that is at least comparable to RQ-PCR and potentially more accurate. PB is a suitable source for serial BCL2/IGH MRD assessments, regardless of the methodology utilized. © 2017 John Wiley & Sons Ltd.

  10. Hexavalent chromium-induced apoptosis of granulosa cells involves selective sub-cellular translocation of Bcl-2 members, ERK1/2 and p53

    International Nuclear Information System (INIS)

    Banu, Sakhila K.; Stanley, Jone A.; Lee, JeHoon; Stephen, Sam D.; Arosh, Joe A.; Hoyer, Patricia B.; Burghardt, Robert C.

    2011-01-01

    Hexavalent chromium (CrVI) has been widely used in industries throughout the world. Increased usage of CrVI and atmospheric emission of CrVI from catalytic converters of automobiles, and its improper disposal causes various health hazards including female infertility. Recently we have reported that lactational exposure to CrVI induced a delay/arrest in follicular development at the secondary follicular stage. In order to investigate the underlying mechanism, primary cultures of rat granulosa cells were treated with 10 μM potassium dichromate (CrVI) for 12 and 24 h, with or without vitamin C pre-treatment for 24 h. The effects of CrVI on intrinsic apoptotic pathway(s) were investigated. Our data indicated that CrVI: (i) induced DNA fragmentation and increased apoptosis, (ii) increased cytochrome c release from the mitochondria to cytosol, (iii) downregulated anti-apoptotic Bcl-2, Bcl-XL, HSP70 and HSP90; upregulated pro-apoptotic BAX and BAD, (iv) altered translocation of Bcl-2, Bcl-XL, BAX, BAD, HSP70 and HSP90 to the mitochondria, (v) upregulated p-ERK and p-JNK, and selectively translocated p-ERK to the mitochondria and nucleus, (vi) activated caspase-3 and PARP, and (vii) increased phosphorylation of p53 at ser-6, ser-9, ser-15, ser-20, ser-37, ser-46 and ser-392, increased p53 transcriptional activation, and downregulated MDM-2. Vitamin C pre-treatment mitigated CrVI effects on apoptosis and related pathways. Our study, for the first time provides a clear insight into the effect of CrVI on multiple pathways that lead to apoptosis of granulosa cells which could be mitigated by vitamin C.

  11. Enhanced stability of Mcl1, a prosurvival Bcl2 relative, blunts stress-induced apoptosis, causes male sterility, and promotes tumorigenesis.

    Science.gov (United States)

    Okamoto, Toru; Coultas, Leigh; Metcalf, Donald; van Delft, Mark F; Glaser, Stefan P; Takiguchi, Megumi; Strasser, Andreas; Bouillet, Philippe; Adams, Jerry M; Huang, David C S

    2014-01-07

    The B-cell CLL/lymphoma 2 (Bcl2) relative Myeloid cell leukemia sequence 1 (Mcl1) is essential for cell survival during development and for tissue homeostasis throughout life. Unlike Bcl2, Mcl1 turns over rapidly, but the physiological significance of its turnover has been unclear. We have gained insight into the roles of Mcl1 turnover in vivo by analyzing mice harboring a modified allele of Mcl1 that serendipitously proved to encode an abnormally stabilized form of Mcl1 due to a 13-aa N-terminal extension. Although the mice developed normally and appeared unremarkable, the homozygous males unexpectedly proved infertile due to defective spermatogenesis, which was evoked by enhanced Mcl1 prosurvival activity. Under unstressed conditions, the modified Mcl1 is present at levels comparable to the native protein, but it is markedly stabilized in cells subjected to stresses, such as protein synthesis inhibition or UV irradiation. Strikingly, the modified Mcl1 allele could genetically complement the loss of Bcl2, because introduction of even a single allele significantly ameliorated the severe polycystic kidney disease and consequent runting caused by Bcl2 loss. Significantly, the development of c-MYC-induced acute myeloid leukemia was also accelerated in mice harboring that Mcl1 allele. Our collective findings reveal that, under certain circumstances, the N terminus of Mcl1 regulates its degradation; that some cell types require degradation of Mcl1 to induce apoptosis; and, most importantly, that rapid turnover of Mcl1 can serve as a tumor-suppressive mechanism.

  12. Genetic dissimilarity between primary colorectal carcinomas and their lymph node metastases: ploidy, p53, bcl-2, and c-myc expression--a pilot study.

    Science.gov (United States)

    Zalata, Khaled Refaat; Elshal, Mohamed Farouk; Foda, Abd AlRahman Mohammad; Shoma, Ashraf

    2015-08-01

    The current paradigm of metastasis proposes that rare cells within primary tumors acquire metastatic capability via sequential mutations, suggesting that metastases are genetically dissimilar from their primary tumors. This study investigated the changes in the level of expression of a well-defined panel of cell proliferation, differentiation, and apoptosis markers between the primary colorectal cancer (CRC) and the corresponding synchronous lymph node (LN) metastasis from the same patients. DNA flow cytometry and immunostaining of p53, bcl-2, and c-myc were carried out on 36 cases of CRC radical resection specimens with their corresponding LN metastases. There was very low probability that the histological patterns of primary tumors and LN metastases are independent (p < 0.001). Metastatic tumors were significantly more diffusely positive for p53 than the primary tumors (p < 0.001). Conversely, primary tumors were significantly more diffusely positive for c-myc than metastatic tumors (p = 0.011). No significant difference was found between the LNs and the primary tumors in bcl-2 positivity (p = 0.538) and DNA aneuploidy (p = 0.35), with a tendency towards negative bcl-2 and less aneuploidy in LN metastases than primary tumors. In conclusion, LN metastatic colorectal carcinomas have a tendency of being less differentiated, with a higher incidence of diffuse p53 staining, lower incidence of bcl-2 staining, and less aneuploidy in comparison to their primary counterparts suggesting a more aggressive biological behavior, which could indicate the necessity for more aggressive adjuvant therapy.

  13. IL-15 regulates Bcl-2 family members Bim and Mcl-1 through JAK/STAT and PI3K/AKT pathways in T cells.

    Science.gov (United States)

    Shenoy, Aparna R; Kirschnek, Susanne; Häcker, Georg

    2014-08-01

    Maintenance of T cells is determined by their survival capacity, which is regulated by Bcl-2 proteins. Cytokines signalling through the common gamma chains such as IL-2, IL-7 and IL-15 are important for T-cell survival but how these cytokines determine the expression of Bcl-2-family proteins is not clear. We report signalling events of cytokines that regulate expression of two key Bcl-2 proteins, pro-apoptotic Bim and anti-apoptotic Mcl-1, in resting C57BL/6 mouse T cells. IL-2, IL-7 and IL-15 inhibited apoptosis but paradoxically induced the expression of Bim, countered by concomitant induction of Mcl-1. Bim induction by IL-15 was found at the mRNA and protein levels and depended on both JAK/STAT and PI3K signals. A new STAT5-binding site was identified in the Bim promoter, which was occupied by STAT5 upon IL-15 stimulation. Although it also depended on JAK/STAT- and PI3K signalling, Mcl-1 regulation was independent of Mcl-1 mRNA levels and of regulation of protein stability, suggesting translational regulation. Concurrent CD3 signals inhibited some of the IL-7 effect but not the IL-15 effect on Bcl-2 proteins. The data suggest that cytokines induce Bim and prime T cells for apoptosis, but also inhibit apoptosis by stabilising Mcl-1. Later downregulation of short-lived Mcl-1 may induce efficient, Bim-dependent apoptosis. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Effects of BCL oral administation and herbal acupuncture at BL18, BL19 on Liver function changes induced by Alcohol in the mice

    Directory of Open Access Journals (Sweden)

    Sa-Hyun Park

    2002-02-01

    Full Text Available This dissertation was designed to evaluate the effect of BCL(refinded Bambusae Caulis in Liqua-men oral administration and herbal acupuncture on alcohol metabolism and liver function. For this study. mice were damaged by a large quantity of alcohol and received treatment of either BCL 1 mg/kg in oral or BCL 250㎍/kg in herbal acupuncture-BL18 . BL19 bilateral. and then such parameters as GOT. GPT. catalase and superoxide dismustase(CuZn-SOD, Mn-SOD were measured. The results of the experiments were summarized as follows. 1. Compared with control group, the proper degree of alcohol in serum was not significantly differ from oral administration group and herbal acupuncture group. 2. Compared with control group. the activity of GOT in serum was significantly reduced both oral administration and herbal acupuncture group. 3. Compared with control group. the activity of GPT in serum was significantly reduced both oral administration and herbal acupuncture group. 4. The activity of catalase in liver cell tissue, compared with control group. was not sigificantly affected either by oral administration and herbal acupuncture group. 5. The activity of CuZn-SOD in liver cell tissue was not significantly change in herbal acupuncture and oral administration group. The activity of Mn-SOD was significantly increased in oral administration group. while it was not the case in acupuncture group. In conclusion. we consider that BCL oral administration and herbal acupuncture is highly effetive in recovering alcohol metabolism and liver disfunction induced by alcohol.

  15. Prognostic significances of overexpression MYC and/or BCL2 in R-CHOP-treated diffuse large B-cell lymphoma: A Systematic review and meta-analysis.

    Science.gov (United States)

    Li, Lu; Li, Yanyan; Que, Ximei; Gao, Xue; Gao, Qian; Yu, Mingxing; Ma, Kaili; Xi, Yanfeng; Wang, Tong

    2018-04-19

    Numerous studies have investigated the prognostic values of MYC and/or BCL2 protein overexpression in diffuse large B-cell lymphoma (DLBCL). However, the results still demonstrate discrepancies among different studies. We aimed to do a systematic review and meta-analysis on the relationships between overexpression MYC and/or BCL2 and DLBCLs treated with rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP). This study followed the guidelines of PRISMA and Cochrane handbook. The hazard ratios (HRs) for overall survival (OS) were pooled to estimate the main effect size. Twenty studies recruited a total of 5576 patients were available for this meta-analysis. The results showed that MYC (HR = 1.96, 95%CI (confidence interval) = 1.69-2.27)without heterogeneity(I 2  = 17.2%, P = 0.280), BCL2 (HR = 1.65, 95%CI = 1.43-1.89, I 2  = 20.7%, P = 0.234) protein overexpression, and co-overexpression (HR = 2.58, 95%CI = 2.19-3.04, I 2  = 17.2%, P = 0.275) had a poor prognosis in R-CHOP treated DLBCL patients, respectively. The current analysis indicated that MYC and/or BCL2 protein overexpression, and particularly co-overexpression was related to short overall survival in R-CHOP treated DLBCL patients, showing that application of the two new biomarkers can help to better stratify DLBCL patients and guide targeted treatment.

  16. Metformin combined with aspirin significantly inhibit pancreatic cancer cell growth in vitro and in vivo by suppressing anti-apoptotic proteins Mcl-1 and Bcl-2

    Science.gov (United States)

    Yue, Wen; Zheng, Xi; Lin, Yong; Yang, Chung S.; Xu, Qing; Carpizo, Darren; Huang, Huarong; DiPaola, Robert S.; Tan, Xiang-Lin

    2015-01-01

    Metformin and aspirin have been studied extensively as cancer preventive or therapeutic agents. However, the effects of their combination on pancreatic cancer cells have not been investigated. Herein, we evaluated the effects of metformin and aspirin, alone or in combination, on cell viability, migration, and apoptosis as well as the molecular changes in mTOR, STAT3 and apoptotic signaling pathways in PANC-1 and BxPC3 cells. Metformin and aspirin, at relatively low concentrations, demonstrated synergistically inhibitory effects on cell viability. Compared to the untreated control or individual drug, the combination of metformin and aspirin significantly inhibited cell migration and colony formation of both PANC-1 and BxPC-3 cells. Metformin combined with aspirin significantly inhibited the phosphorylation of mTOR and STAT3, and induced apoptosis as measured by caspase-3 and PARP cleavage. Remarkably, metformin combined with aspirin significantly downregulated the anti-apoptotic proteins Mcl-1 and Bcl-2, and upregulated the pro-apoptotic proteins Bim and Puma, as well as interrupted their interactions. The downregulation of Mcl-1 and Bcl-2 was independent of AMPK or STAT3 pathway but partially through mTOR signaling and proteasome degradation. In a PANC-1 xenograft mouse model, we demonstrated that the combination of metformin and aspirin significantly inhibited tumor growth and downregulated the protein expression of Mcl-1 and Bcl-2 in tumors. Taken together, the combination of metformin and aspirin significantly inhibited pancreatic cancer cell growth in vitro and in vivo by regulating the pro- and anti-apoptotic Bcl-2 family members, supporting the continued investigation of this two drug combination as chemopreventive or chemotherapeutic agents for pancreatic cancer. PMID:26056043

  17. RLIP76-dependent suppression of PI3K/AKT/Bcl-2 pathway by miR-101 induces apoptosis in prostate cancer

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Jing; Song, Qi; Cai, Yi; Wang, Peng; Wang, Min; Zhang, Dong, E-mail: zhangd1117@yahoo.com

    2015-08-07

    MicroRNA-101 (miR-101) participates in carcinogenesis and tumor progression in various cancers. However, its biological functions in prostate cancer are still unclear. Here, we demonstrate that miR-101 represents a critical role in regulating cell apoptosis in prostate cancer cells. We first demonstrated that miR-101 treatment promoted apoptosis in DU145 and PC3 cells by using flow cytometric analysis and transmission electron microscopy (TEM). To verify the mechanisms, we identified a novel miR-101 target, Ral binding protein 1 (RLIP76). We found miR-101 transfection significantly suppresses RLIP76 expression, which can transactivate phosphorylation of PI3K-Akt signaling, and resulted in an amplification of Bcl2-induced apoptosis. Furthermore, we demonstrated that RLIP76 overexpression could reverse the anti-tumor effects of miR-101 in DU145 and PC3 cells by using flow cytometry assay and MTT assay. Taken together, our results revealed that the effect of miR-101 on prostate cancer cell apoptosis was due to RLIP76 regulation of the PI3K/Akt/Bcl-2 signaling pathway. - Highlights: • miR-101 inhibited prostate cancer cell proliferation and enhanced apoptosis. • miR-101 directly targeted and regulated RLIP76 expression. • miR-101 suppressed PI3K/Akt/Bcl-2 signaling pathway by targeting RLIP76.

  18. Influence of intra-tumoral heterogeneity on the evaluation of BCL2, E-cadherin, EGFR, EMMPRIN, and Ki-67 expression in tissue microarrays from breast cancer

    DEFF Research Database (Denmark)

    Tramm, Trine; Kyndi, Marianne; Sørensen, Flemming B

    2018-01-01

    -tumoral heterogeneity as well as inter-observer variability on the evaluation of various IHC markers with potential prognostic impact in breast cancer (BCL2, E-cadherin, EGFR, EMMPRIN and Ki-67). MATERIAL AND METHODS: From each of 27 breast cancer patients, two tumor-containing paraffin blocks were chosen. Intra...... was found. EMMPRIN and Ki-67 showed a more heterogeneous expression with moderate to substantial intra-block agreements. For both stainings, there was a moderate inter-block agreement that improved slightly for EMMPRIN, when using WS instead of TMA cores. Inter-observer agreements were found to be almost...... perfect for BCL2, E-cadherin and EGFR (WS: κ > 0.82, TMAs: κ > 0.90), substantial for EMMPRIN (κ > 0.63), but only fair to moderate for Ki-67 (WS: κ = 0.54, TMAs: κ = 0.33). CONCLUSIONS: BCL2, E-cadherin and EGFR were found to be homogeneously expressed, whereas EMMPRIN and Ki-67 showed a more pronounced...

  19. Inhibition of hemangioma development in a syngeneic mouse model correlates with bcl-2 suppression and the inhibition of Akt kinase activity.

    Science.gov (United States)

    Mabeta, Peace; Pepper, Michael S

    2012-03-01

    Hemangiomas are benign vascular tumors that are characterised by excessive angiogenesis. While there is no definitive treatment for these tumors, several angiogenesis inhibitors, including bleomycin, have been employed. To better understand the mechanism of bleomycin in accelerating haemangioma regression, we investigated the effects of the drug on hemangiomagenesis using a previously described mouse hemangioma model. The effects of bleomycin were tested in mice injected with endothelioma cells to induce hemangioma development. At termination, tissue samples from bleomycin-treated and control mice were stained with hematoxylin and eosin for histological examination. Bcl-2, flk-1 and vWF expression were studied by immunofluorescence microscopy. Hematological analysis was undertaken using a hemocounter. Akt activity was analyzed in tissue homogenates and endothelioma cells using ELISA. Also, caspase activity was analysed in endothelioma cells by ELISA. Bleomycin inhibited tumor growth in vivo in a dose-dependant manner. Our findings also revealed that bleomycin inhibited Akt activation and suppressed bcl-2. In vitro bleomycin increased caspase activation. Our observations reveal possible mechanisms for the inhibitory effects of bleomycin on hemangiomagenesis, and raise the possibility that bcl-2 might be an important therapeutic target in the treatment of hemangiomas.

  20. The effect of Ginkgo biloba extract treatment in the Bcl-2 expression by osteoblasts in the femoral trabecular bone of Wistar rats with glucocorticoid-induced osteoporosis

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    Leda M.F. Lucinda

    Full Text Available Evaluate the effect of the extract of Ginkgo biloba L., Ginkgoaceae (EGb in the Bcl-2 expression by osteoblasts in the femoral trabecular bone of Wistar rats with glucocorticoid-induced osteoporosis. Rats were divided into five groups: osteoporosis; EGb1 (28 mg/kg; EGb2 (56 mg/kg; alendronate (0.2 mg/animal and control. The treatments were conducted for 20 or 30 days. The Bcl-2 expression by osteoblasts cells was evaluated in the femoral trabecular bone. The control group was compared with the osteoporosis-induced group (Student's t-test. The other groups were analyzed by ANOVA test followed by Tukey's test (p < 0.05. The percentage of Bcl-2 expression was reduced, when the control group (17.95 ± 3.45 20 days; 21.11 ± 3.43 30 days was compared with the osteoporosis group (10.64 ± 3.30 20 days; 9.72 ± 2.84 30 days. Nevertheless, this percentage increased in the EGb2 group (18.58 ± 3.41 20 days; 16.51 ± 1.80 30 days when compared to the osteoporosis group. The EGb increased the expression of the anti-apoptotic protein, suggesting a decrease in osteoblast apoptosis.

  1. Tumor suppressor PDCD4 modulates miR-184-mediated direct suppression of C-MYC and BCL2 blocking cell growth and survival in nasopharyngeal carcinoma.

    Science.gov (United States)

    Zhen, Yan; Liu, Zhen; Yang, Huiling; Yu, Xiaoli; Wu, Qiangyun; Hua, Shengni; Long, Xiaobin; Jiang, Qingping; Song, Ye; Cheng, Chao; Wang, Hao; Zhao, Menyang; Fu, Qiaofen; Lyu, Xiaoming; Chen, Yiyu; Fan, Yue; Liu, Yan; Li, Xin; Fang, Weiyi

    2013-10-24

    Programmed cell death 4 (PDCD4), a novel tumor suppressor, inhibits cell proliferation, migration and invasion as well as promotes cell apoptosis in tumors. However, the molecular mechanism of its tumor-suppressive function remains largely unknown in tumors including nasopharyngeal carcinoma (NPC). In this study, downregulated PDCD4 expression was significantly associated with the status of NPC progression and poor prognosis. PDCD4 markedly suppressed the ability of cell proliferation and cell survival by modulating C-MYC-controlled cell cycle and BCL-2-mediated mitochondrion apoptosis resistance signals, and oncogenic transcription factor C-JUN in NPC. Furthermore, miR-184, a tumor-suppressive miRNA modulated by PDCD4 directly targeting BCL2 and C-MYC, participated in PDCD4-mediated suppression of cell proliferation and survival in NPC. Further, we found that PDCD4 decreased the binding of C-Jun to the AP-1 element on the miR-184 promoter regions by PI3K/AKT/JNK/C-Jun pathway and stimulated miR-184 expression. In clinical fresh specimens, reduced PDCD4 mRNA level was positively correlated with miR-184 expression in NPC. Our studies are the first to demonstrate that PDCD4 as tumor suppressor regulated miR-184-mediated direct targeting of BCL2 and C-MYC via PI3K/AKT and JNK/C-Jun pathway attenuating cell proliferation and survival in NPC.

  2. IAP antagonists Birinapant and AT-406 efficiently synergise with either TRAIL, BRAF, or BCL-2 inhibitors to sensitise BRAFV600E colorectal tumour cells to apoptosis.

    Science.gov (United States)

    Perimenis, Philippos; Galaris, Apostolos; Voulgari, Alexandra; Prassa, Margarita; Pintzas, Alexander

    2016-08-12

    High expression levels of Inhibitors of Apoptosis Proteins (IAPs) have been correlated with poor cancer prognosis and block the cell death pathway by interfering with caspase activation. SMAC-mimetics are small-molecule inhibitors of IAPs that mimic the endogenous SMAC and promote the induction of cell death by neutralizing IAPs. In this study, anti-tumour activity of new SMAC-mimetics Birinapant and AT-406 is evaluated against colorectal adenocarcinoma cells and IAP cross-talk with either oncogenic BRAF or BCL-2, or with the TRAIL are further exploited towards rational combined protocols. It is shown that pre-treatment of SMAC-mimetics followed by their combined treatment with BRAF inhibitors can decrease cell viability, migration and can very efficiently sensitize colorectal tumour cells to apoptosis. Moreover, co-treatment of TRAIL with SMAC-mimetics can efficiently sensitize resistant tumour cells to apoptosis synergistically, as shown by median effect analysis. Finally, Birinapant and AT-406 can synergise with BCL-2 inhibitor ABT-199 to reduce viability of adenocarcinoma cells with high BCL-2 expression. Proposed synergistic rational anticancer combined protocols of IAP antagonists Birinapant and AT-406 in 2D and 3D cultures can be later further exploited in vivo, from precision tumour biology to precision medical oncology.

  3. Spontaneous loss of B lineage transcription factors leads to pre-B leukemia in Ebf1+/–Bcl-xLTg mice

    Science.gov (United States)

    Ramírez-Komo, J A; Delaney, M A; Straign, D; Lukin, K; Tsang, M; Iritani, B M; Hagman, J

    2017-01-01

    Early B-cell factor 1 (EBF1) plays a central role in B-cell lineage specification and commitment. Loss of this critical transcription factor is strongly associated with high-risk, relapsed and therapy-resistant B–cell-acute lymphoblastic leukemia, especially in children. However, Ebf1 haploinsufficient mice exhibit a normal lifespan. To determine whether prolonged survival of B cells would enable tumorigenesis in Ebf1 haploinsufficient animals, we generated Ebf1+/–Bcl-xLTg mice, which express the anti-apoptotic factor Bcl-xL in B cells. Approximately half of Ebf1+/–Bcl-xLTg mice develop aggressive oligoclonal leukemia as they age, which engrafts in congenic wild-type recipients without prior conditioning. The neoplastic cells display a pre-B phenotype and express early developmental- and natural killer cell/myeloid-markers inappropriately. In addition, we found tumor cell-specific loss of several transcription factors critical for maintaining differentiation: EBF1, TCF3 and RUNX1. However, in the majority of tumors, loss of Ebf1 expression was not due to loss of heterozygosity. This is the first spontaneous mouse model of pre-B leukemia to demonstrate inappropriate expression of non-B-cell-specific genes associated with loss of Ebf1, Tcf3 and Runx1 expression. PMID:28692033

  4. Bcl-2 over-expression fails to prevent age-related loss of calretinin positive neurons in the mouse dentate gyrus

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    Han Mingbo

    2006-08-01

    Full Text Available Abstract Background Cognitive performance declines with increasing age. Possible cellular mechanisms underlying this age-related functional decline remain incompletely understood. Early studies attributed this functional decline to age-related neuronal loss. Subsequent studies using unbiased stereological techniques found little or no neuronal loss during aging. However, studies using specific cellular markers found age-related loss of specific neuronal types. To test whether there is age-related loss of specific neuronal populations in the hippocampus, and subsequently, whether over-expression of the B-cell lymphoma protein-2 (Bcl-2 in these neurons could delay possible age-related neuronal loss, we examined calretinin (CR positive neurons in the mouse dentate gyrus during aging. Result In normal mice, there was an age-related loss of CR positive cells in the dentate gyrus. At the same region, there was no significant decrease of total numbers of neurons, which suggested that age-related loss of CR positive cells was due to the decrease of CR expression in these cells instead of cell death. In the transgenic mouse line over-expressing Bcl-2 in neurons, there was an age-related loss of CR positive cells. Interestingly, there was also an age-related neuronal loss in this transgenic mouse line. Conclusion These data suggest an age-related loss of CR positive neurons but not total neuronal loss in normal mice and this age-related neuronal change is not prevented by Bcl-2 over-expression.

  5. Phosphorylation of Rad9 at serine 328 by cyclin A-Cdk2 triggers apoptosis via interfering Bcl-xL.

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    Zhuo Zhan

    Full Text Available Cyclin A-Cdk2, a cell cycle regulated Ser/Thr kinase, plays important roles in a variety of apoptoticprocesses. However, the mechanism of cyclin A-Cdk2 regulated apoptosis remains unclear. Here, we demonstrated that Rad9, a member of the BH3-only subfamily of Bcl-2 proteins, could be phosphorylated by cyclin A-Cdk2 in vitro and in vivo. Cyclin A-Cdk2 catalyzed the phosphorylation of Rad9 at serine 328 in HeLa cells during apoptosis induced by etoposide, an inhibitor of topoisomeraseII. The phosphorylation of Rad9 resulted in its translocation from the nucleus to the mitochondria and its interaction with Bcl-xL. The forced activation of cyclin A-Cdk2 in these cells by the overexpression of cyclin A,triggered Rad9 phosphorylation at serine 328 and thereby promoted the interaction of Rad9 with Bcl-xL and the subsequent initiation of the apoptotic program. The pro-apoptotic effects regulated by the cyclin A-Cdk2 complex were significantly lower in cells transfected with Rad9S328A, an expression vector that encodes a Rad9 mutant that is resistant to cyclin A-Cdk2 phosphorylation. These findings suggest that cyclin A-Cdk2 regulates apoptosis through a mechanism that involves Rad9phosphorylation.

  6. AS1411-Induced Growth Inhibition of Glioma Cells by Up-Regulation of p53 and Down-Regulation of Bcl-2 and Akt1 via Nucleolin.

    Directory of Open Access Journals (Sweden)

    Ye Cheng

    Full Text Available AS1411 binds nucleolin (NCL and is the first oligodeoxynucleotide aptamer to reach phase I and II clinical trials for the treatment of several cancers. However, the mechanisms by which AS1411 targets and kills glioma cells and tissues remain unclear. Here we report that AS1411 induces cell apoptosis and cycle arrest, and inhibits cell viability by up-regulation of p53 and down-regulation of Bcl-2 and Akt1 in human glioma cells. NCL was overexpressed in both nucleus and cytoplasm in human glioma U87, U251 and SHG44 cells compared to normal human astrocytes (NHA. AS1411 bound NCL and inhibited the proliferation of glioma cells but not NHA, which was accompanied with up-regulation of p53 and down-regulation of Bcl-2 and Akt1. Moreover, AS1411 treatment resulted in the G2/M cell cycle arrest in glioma cells, which was however abolished by overexpression of NCL. Further, AS1411 induced cell apoptosis, which was prevented by silencing of p53 and overexpression of Bcl-2. In addition, AS1411 inhibited the migration and invasion of glioma cells in an Akt1-dependent manner. Importantly, AS1411 inhibited the growth of glioma xenograft and prolonged the survival time of glioma tumor-bearing mice. These results revealed a promising treatment of glioma by oligodeoxynucleotide aptamer.

  7. Role of P53 and BCL-2 in high-risk breast cancer patients treated with adjuvant anthracycline-based chemotherapy.

    Science.gov (United States)

    Mottolese, M; Benevolo, M; Del Monte, G; Buglioni, S; Papaldo, P; Nisticò, C; Di Filippo, F; Vasselli, S; Vici, P; Botti, C

    2000-12-01

    Adjuvant therapy has become an integral component of the managment of primary high-risk breast cancer patients. However, a considerable fraction of women receive no benefit from this treatment. This study investigates whether a number of biopathological factors can influence the outcome of patients submitted to adjuvant chemotherapy involving the use of high-dose epirubicin and cyclophosphamide. One hundred and fifty-seven primary breast cancer patients, considered at high risk according to the St. Gallen Meeting Consensus Conference, were evaluated immunohistochemically for estrogen, progesterone receptors, p53, bcl-2, HER-2/neu, and Ki-67, of which the results were correlated with patient outcome. Results obtained demonstrated that p53 is a significant predictor of disease-free survival (DFS P < 0.0001) and overall survival (OS P = 0.0002) both in ductal and lobular carcinomas, whereas bcl-2 expression seems to be of prognostic value only in lobular carcinomas (DFS P = 0.01; OS P = 0.02). This data indicates that in high-risk breast cancer patients the immunohistochemical evaluation of p53 and bcl-2 may be of clinical value in distinguishing different responses to adjuvant anthracycline-based chemotherapy.

  8. Microwave-Assisted Synthesis of Imidazo[4,5-f][1,10]phenanthroline Derivatives as Apoptosis Inducers in Chemotherapy by Stabilizing Bcl-2 G-quadruplex DNA

    Directory of Open Access Journals (Sweden)

    Li Li

    2017-05-01

    Full Text Available Herein, a series of imidazo[4,5-f][1,10] phenanthroline derivatives RPIP (PIP = imidazo [4,5-f][1,10] phenanthroline, R = NO2, 1; CF3, 2; Cl, 3; OH, 4 have been synthesized in yields of 82.3–94.7% at 100 °C under the irradiation of microwave. MTT assay has been utilized to evaluate the inhibitory activity (IC50 of these compounds against the growth of various tumor cells, and the results revealed that these compounds, especially 1, exhibited excellent inhibitory activity against the growth of A549 cells with IC50 of 15.03 μM. Moreover, it’s also confirmed that 1 can penetrate into the membrane of tumor cells and distribute in mitochondria when observed under microscopy, resulting apoptosis of tumor cells. The further studies showed that 1 can bind to bcl-2 G-quadruplex DNA, which demonstrated by the increase of melting point of bcl-2 G4 DNA in the presence of 1, as well as electronic titration and emission spectra. In a word, this kind of compound may develop as a potential apoptosis inducer in cancer chemotherapy via binding and stabilizing to the bcl-2 G-quadruplex DNA.

  9. [Survival of patients with primary central nervous system diffuse large B-cell lymphoma: impact of gene aberrations and protein overexpression of bcl-2 and C-MYC, and selection of chemotherapy regimens].

    Science.gov (United States)

    Yin, W J; Zhu, X; Yang, H Y; Sun, W Y; Wu, M J

    2018-01-08

    Objective: To investigate the impact of clinicopathological features, gene rearrangements and protein expression of bcl-6, bcl-2, C-MYC and chemotherapy regime on the prognosis of patients with primary central nervous system diffuse large B-cell lymphoma (PCNS-DLBCL). Methods: Thirty-three cases of PCNS-DLBCL diagnosed from January 2006 to December 2016 at Zhejiang Cancer Hospital were collected. The expression of CD10, bcl-6, bcl-2, MUM1 and MYC were detected by immunohistochemical staining (IHC). The presence of EB virus was detected by in situ hybridization(EBER). Copy number variation (ICN) and translocation status of bcl-6, bcl-2 and C-MYC genes were detected by fluorescence in situ hybridization (FISH). The relationship between the above indexes and the prognosis was analyzed by univariate, bivariate survival analysis and multiple Cox hazard regression analysis. Results: The study included 33