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Sample records for antiapoptotic bcl-2 proteins

  1. Antiapoptotic Bcl-2 protein as a potential target for cancer therapy: A mini review.

    Science.gov (United States)

    Jagani, Hitesh; Kasinathan, Narayanan; Meka, Sreenivasa Reddy; Josyula, Venkata Rao

    2016-08-01

    Bcl-2, an antiapoptotic protein, is considered as a potential target in cancer treatment since its oncogenic potential has been proven and is well documented. Antisense technology and RNA interference (RNAi) have been used to reduce the expression of the Bcl-2 gene in many types of cancer cells and are effective as adjuvant therapy along with the chemotherapeutic agents. The lack of appropriate delivery systems is considered to be the main hurdle associated with the RNAi. In this review, we discuss the antiapoptotic Bcl-2 protein, its oncogenic potential, and various approaches utilized to target Bcl-2 including suitable delivery systems employed for successful delivery of siRNA. PMID:25801037

  2. Inhibition of Antiapoptotic BCL-XL, BCL-2, and MCL-1 Proteins by Small Molecule Mimetics

    Directory of Open Access Journals (Sweden)

    D.S. Dalafave

    2010-08-01

    Full Text Available Informatics and computational design methods were used to create new molecules that could potentially bind antiapoptotic proteins, thus promoting death of cancer cells. Apoptosis is a cellular process that leads to the death of damaged cells. Its malfunction can cause cancer and poor response to conventional chemotherapy. After being activated by cellular stress signals, proapoptotic proteins bind antiapoptotic proteins, thus allowing apoptosis to go forward. An excess of antiapoptotic proteins can prevent apoptosis. Designed molecules that mimic the roles of proapoptotic proteins can promote the death of cancer cells. The goal of our study was to create new putative mimetics that could simultaneously bind several antiapoptotic proteins. Five new small molecules were designed that formed stable complexes with BCL-2, BCL-XL, and MCL-1 antiapoptotic proteins. These results are novel because, to our knowledge, there are not many, if any, small molecules known to bind all three proteins. Drug-likeness studies performed on the designed molecules, as well as previous experimental and preclinical studies on similar agents, strongly suggest that the designed molecules may indeed be promising drug candidates. All five molecules showed “drug-like” properties and had overall drug-likeness scores between 81% and 96%. A single drug based on these mimetics should cost less and cause fewer side effects than a combination of drugs each aimed at a single protein. Computer-based molecular design promises to accelerate drug research by predicting potential effectiveness of designed molecules prior to laborious experiments and costly preclinical trials.

  3. Selective peptide inhibitors of antiapoptotic cellular and viral Bcl-2 proteins lead to cytochrome c release during latent Kaposi’s sarcoma-associated herpesvirus infection

    OpenAIRE

    Burrer, Christine M.; Foight, Glenna W.; Keating, Amy E.; Chan, Gary C.

    2015-01-01

    Kaposi’s sarcoma-associated herpesvirus (KSHV) is associated with B-cell lymphomas including primary effusion lymphoma and multicentric Castleman’s disease. KSHV establishes latency within B cells by modulating or mimicking the antiapoptotic Bcl-2 family of proteins to promote cell survival. Our previous BH3 profiling analysis, a functional assay that assesses the contribution of Bcl-2 proteins towards cellular survival, identified two Bcl-2 proteins, cellular Mcl-1 and viral KsBcl-2, as pote...

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

    International Nuclear Information System (INIS)

    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

  5. Active fragments from pro- and antiapoptotic BCL-2 proteins have distinct membrane behavior reflecting their functional divergence.

    Directory of Open Access Journals (Sweden)

    Yannis Guillemin

    Full Text Available BACKGROUND: The BCL-2 family of proteins includes pro- and antiapoptotic members acting by controlling the permeabilization of mitochondria. Although the association of these proteins with the outer mitochondrial membrane is crucial for their function, little is known about the characteristics of this interaction. METHODOLOGY/PRINCIPAL FINDINGS: Here, we followed a reductionist approach to clarify to what extent membrane-active regions of homologous BCL-2 family proteins contribute to their functional divergence. Using isolated mitochondria as well as model lipid Langmuir monolayers coupled with Brewster Angle Microscopy, we explored systematically and comparatively the membrane activity and membrane-peptide interactions of fragments derived from the central helical hairpin of BAX, BCL-xL and BID. The results show a connection between the differing abilities of the assayed peptide fragments to contact, insert, destabilize and porate membranes and the activity of their cognate proteins in programmed cell death. CONCLUSION/SIGNIFICANCE: BCL-2 family-derived pore-forming helices thus represent structurally analogous, but functionally dissimilar membrane domains.

  6. A novel BH3 mimetic efficiently induces apoptosis in melanoma cells through direct binding to anti-apoptotic Bcl-2 family proteins, including phosphorylated Mcl-1.

    Science.gov (United States)

    Liu, Yubo; Xie, Mingzhou; Song, Ting; Sheng, Hongkun; Yu, Xiaoyan; Zhang, Zhichao

    2015-03-01

    The Bcl-2 family modulates sensitivity to chemotherapy in many cancers, including melanoma, in which the RAS/BRAF/MEK/ERK pathway is constitutively activated. Mcl-1, a major anti-apoptotic protein in the Bcl-2 family, is extensively expressed in melanoma and contributes to melanoma's well-documented chemoresistance. Here, we provide the first evidence that Mcl-1 phosphorylation at T163 by ERK1/2 and JNK is associated with the resistance of melanoma cell lines to the existing BH3 mimetics gossypol, S1 and ABT-737, and a novel anti-apoptotic mechanism of phosphorylated Mcl-1 (pMcl-1) is revealed. pMcl-1 antagonized the known BH3 mimetics by sequestering pro-apoptotic proteins that were released from Bcl-2/Mcl-1. Furthermore, an anthraquinone BH3 mimetic, compound 6, was identified to be the first small molecule to that induces endogenous apoptosis in melanoma cells by directly binding Bcl-2, Mcl-1, and pMcl-1 and disrupting the heterodimers of these proteins. Although compound 6 induced upregulation of the pro-apoptotic protein Noxa, its apoptotic induction was independent of Noxa. These data reveal the promising therapeutic potential of targeting pMcl-1 to treat melanoma. Compound 6 is therefore a potent drug that targets pMcl-1 in melanoma.

  7. Interaction of a putative BH3 domain of clusterin with anti-apoptotic Bcl-2 family proteins as revealed by NMR spectroscopy

    International Nuclear Information System (INIS)

    Highlights: → Identification of a conserved BH3 motif in C-terminal coiled coil region of nCLU. → The nCLU BH3 domain binds to BH3 peptide-binding grooves in both Bcl-XL and Bcl-2. → A conserved binding mechanism of nCLU BH3 and the other pro-apoptotic BH3 peptides with Bcl-XL. → The absolutely conserved Leu323 and Asp328 of nCLU BH3 domain are critical for binding to Bcl-XL. → Molecular understanding of the pro-apoptotic function of nCLU as a novel BH3-only protein. -- Abstract: Clusterin (CLU) is a multifunctional glycoprotein that is overexpressed in prostate and breast cancers. Although CLU is known to be involved in the regulation of apoptosis and cell survival, the precise molecular mechanism underlying the pro-apoptotic function of nuclear CLU (nCLU) remains unclear. In this study, we identified a conserved BH3 motif in C-terminal coiled coil (CC2) region of nCLU by sequence analysis and characterized the molecular interaction of the putative nCLU BH3 domain with anti-apoptotic Bcl-2 family proteins by nuclear magnetic resonance (NMR) spectroscopy. The chemical shift perturbation data demonstrated that the nCLU BH3 domain binds to pro-apoptotic BH3 peptide-binding grooves in both Bcl-XL and Bcl-2. A structural model of the Bcl-XL/nCLU BH3 peptide complex reveals that the binding mode is remarkably similar to those of other Bcl-XL/BH3 peptide complexes. In addition, mutational analysis confirmed that Leu323 and Asp328 of nCLU BH3 domain, absolutely conserved in the BH3 motifs of BH3-only protein family, are critical for binding to Bcl-XL. Taken altogether, our results suggest a molecular basis for the pro-apoptotic function of nCLU by elucidating the residue specific interactions of the BH3 motif in nCLU with anti-apoptotic Bcl-2 family proteins.

  8. Interaction of a putative BH3 domain of clusterin with anti-apoptotic Bcl-2 family proteins as revealed by NMR spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Dong-Hwa; Ha, Ji-Hyang [Medical Proteomics Research Center, KRIBB, Daejeon 305-806 (Korea, Republic of); Kim, Yul [Department of Bio and Brain Engineering, KAIST, Daejeon 305-701 (Korea, Republic of); Bae, Kwang-Hee [Medical Proteomics Research Center, KRIBB, Daejeon 305-806 (Korea, Republic of); Park, Jae-Yong [Department of Physiology, Institute of Health Science, School of Medicine, Gyeongsang National University, Jinju, Gyeongnam 660-751 (Korea, Republic of); Choi, Wan Sung [Department of Anatomy and Neurobiology, Institute of Health Science, School of Medicine, Gyeongsang National University, Jinju, Gyeongnam 660-751 (Korea, Republic of); Yoon, Ho Sup [Division of Structural and Computational Biology, School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637511 (Singapore); Park, Sung Goo; Park, Byoung Chul [Medical Proteomics Research Center, KRIBB, Daejeon 305-806 (Korea, Republic of); Yi, Gwan-Su, E-mail: gsyi@kaist.ac.kr [Department of Bio and Brain Engineering, KAIST, Daejeon 305-701 (Korea, Republic of); Chi, Seung-Wook, E-mail: swchi@kribb.re.kr [Medical Proteomics Research Center, KRIBB, Daejeon 305-806 (Korea, Republic of)

    2011-05-20

    Highlights: {yields} Identification of a conserved BH3 motif in C-terminal coiled coil region of nCLU. {yields} The nCLU BH3 domain binds to BH3 peptide-binding grooves in both Bcl-X{sub L} and Bcl-2. {yields} A conserved binding mechanism of nCLU BH3 and the other pro-apoptotic BH3 peptides with Bcl-X{sub L}. {yields} The absolutely conserved Leu323 and Asp328 of nCLU BH3 domain are critical for binding to Bcl-X{sub L.} {yields} Molecular understanding of the pro-apoptotic function of nCLU as a novel BH3-only protein. -- Abstract: Clusterin (CLU) is a multifunctional glycoprotein that is overexpressed in prostate and breast cancers. Although CLU is known to be involved in the regulation of apoptosis and cell survival, the precise molecular mechanism underlying the pro-apoptotic function of nuclear CLU (nCLU) remains unclear. In this study, we identified a conserved BH3 motif in C-terminal coiled coil (CC2) region of nCLU by sequence analysis and characterized the molecular interaction of the putative nCLU BH3 domain with anti-apoptotic Bcl-2 family proteins by nuclear magnetic resonance (NMR) spectroscopy. The chemical shift perturbation data demonstrated that the nCLU BH3 domain binds to pro-apoptotic BH3 peptide-binding grooves in both Bcl-X{sub L} and Bcl-2. A structural model of the Bcl-X{sub L}/nCLU BH3 peptide complex reveals that the binding mode is remarkably similar to those of other Bcl-X{sub L}/BH3 peptide complexes. In addition, mutational analysis confirmed that Leu323 and Asp328 of nCLU BH3 domain, absolutely conserved in the BH3 motifs of BH3-only protein family, are critical for binding to Bcl-X{sub L}. Taken altogether, our results suggest a molecular basis for the pro-apoptotic function of nCLU by elucidating the residue specific interactions of the BH3 motif in nCLU with anti-apoptotic Bcl-2 family proteins.

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

    DEFF Research Database (Denmark)

    Straten, Per thor; 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......, 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......-cancer immunotherapeutic strategies, alone or in the combination with conventional therapy. Here, we summarize the current knowledge of Bcl-2 family proteins as T-cell antigens, which has set the stage for the first explorative trial using these antigens in therapeutic vaccinations against cancer, and discuss future...

  10. Phenazine-1-carboxamide (PCN) from Pseudomonas sp. strain PUP6 selectively induced apoptosis in lung (A549) and breast (MDA MB-231) cancer cells by inhibition of antiapoptotic Bcl-2 family proteins.

    Science.gov (United States)

    Kennedy, R Kamaraj; Veena, V; Naik, P Ravindra; Lakshmi, Pragna; Krishna, R; Sudharani, S; Sakthivel, N

    2015-06-01

    Phenazine-1-carboxamide (PCN), a naturally occurring simple phenazine derivative isolated from Pseudomonas sp. strain PUP6, exhibited selective cytotoxic activity against lung (A549) and breast (MDA-MB-231) cancer cell lines in differential and dose-dependent manner compared to normal peripheral blood mononuclear cells. PCN-treated cancer cells showed the induction of apoptosis as evidenced by the release of low level of LDH, morphological characteristics, production of reactive oxygen species, loss of mitochondrial membrane potential (ΔΨm) and induction of caspase-3. At molecular level, PCN instigates apoptosis by mitochondrial intrinsic apoptotic pathway via the overexpression of p53, Bax, cytochrome C release and activation of caspase-3 with the inhibition of oncogenic anti-apoptotic proteins such as PARP and Bcl-2 family proteins (Bcl-2, Bcl-w and Bcl-xL). The in silico docking studies of PCN targeted against the anti-apoptotic members of Bcl-2 family proteins revealed the interaction of PCN with the BH3 domain, which might lead to the induction of apoptosis due to the inhibition of antiapoptotic proteins. Due to its innate inhibition potential of antiapoptotic Bcl-2 family proteins, PCN may be used as potent anticancer agent against both lung and breast cancer.

  11. Expression of anti-apoptotic protein Bcl-2 and pro-apoptotic protein Bax after delayed paraplegia induced by ischemia/reperfusion injury

    Institute of Scientific and Technical Information of China (English)

    Bibo Liu; Miao Liu; Duoning Wang; Wei Ma; Shengli Dang

    2006-01-01

    BACKGROUND:Operation of spine does not involve in spinal cord;however,spinal cord injury occurs at post-operation induced by unclear factors.Meanwhile,after decompression of lumbar spinal canal,symptoms are severer and severer.In addition,during extirpation of oervical and lumbar intervertabral disc,spinal cord and its vessels are not damaged,but spinal cord injury is also suffered from patients with partial improvement.All statuses mentioned above are related to expressed changes of bc/-2 gene inhibiting apoptosis and bax gene accelerating apoptosis.OBJECTIVE:To observe motor function of hindlimbs of ischemia/reperfusion model in rabbits at various time points after reperfusion and expressions of apoptosis correlated protein Bcl-2 and Bax.DESIGN:Completely randomized grouping design and contrast study.SEITING:Department of Orthopedics,the First Affiliated Hospital of Medical School,Xi'an Jiao Tong University.MATERIALS:Forty-eight New Zealand white rabbits of both genders were randomly divided into sham operation group(n=24) and model group(n=24),and then,rabbits in each group were observed at four time points:8,24,72 and 168 hours after reperfusion,with 6 in each time point.Rabbit-anti-rabbit Bcl-2 antibody and rabbit-anti-rabbit Bax antibody were provided by Boster Company.The procedures were accordant to the METHODS:The experiment was carried out at Laboratory of Orthopaedics of First Affiliated Hospital of Medical School,Xi'an Jiao Tong University from April to August 2005.①Delayed paralysis models of spinal cord after ischemia/reperfusion were established based on method of Zivin et al.Animals in sham operation group underwent an exposure of abdominal aorta but the aorta was not occluded.②Motor function of hindlimb was observed 8,24,72 and 168 hours after reperfusion.A grade of 0-5 was assigned to each animal (grade 0:no voluntary hind limb function;grade 5:normal hop;grades 0-3:paraplegia).③The lumbar segment of the spinal cord(L3 to L5)was used for

  12. 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

  13. Expression of HER-2 in MCF-7 breast cancer cells modulates anti-apoptotic proteins Survivin and Bcl-2 via the extracellular signal-related kinase (ERK) and phosphoinositide-3 kinase (PI3K) signalling pathways

    International Nuclear Information System (INIS)

    The oncoprotein HER-2 is over-expressed and/or has undergone gene amplification in between 20 to 30% of breast and ovarian cancers. HER-2 amplified breast cancer is associated with a poor prognosis and increased resistance to chemo- and hormonal therapy. Data supporting the transforming potential of HER-2 are irrefutable but the mechanism by which HER-2 contributes to this process is complex and a unified model of HER2-induced increased cell proliferation and survival has not emerged. To understand the initial event(s) that take place by HER-2 over expression, we studied the effect of short term induction of HER-2 expression in the MCF7 breast cancer cell line. We examined the modulation of apoptotic pathways by tetracycline-regulated HER-2 expression for 48 hrs in the MCF7 breast cancer cell line. Specific inhibitors were used to determine signalling pathways that are required for HER-2 induced up-regulation of survivin. Tetracycline regulated short term over expression of HER-2 in the MCF7 cell line increased the antiapoptotic proteins Bcl-2 and survivin levels. Significant increase of extracellular signal-related kinase (ERK) activation but not AKT1, AKT2 and STAT3 was observed in HER-2 over-expressing MCF7 cells. Specific inhibitors of ERK, and phosphoinositide-3 kinase (PI3K), inhibited the HER-2 induced up-regulation of survivin. We did not observe a change in survivin and NF-κB promoter activity in HER-2 expressing MCF7 cells. Our results indicate that short term over expression of HER-2 up regulates antiapoptotic proteins Bcl-2 and survivin in MCF7 cells. We determined that survivin is up-regulated via ERK activation and PI3K signalling. Additionally we show that survivin up-regulation is not at transcriptional level. These data provide insight into the mechanism(s) by which induction of HER-2 over expression up-regulates survivin and Bcl-2 and identifies new targets for therapy of breast cancer

  14. 5-HT2 receptor blocker sarpogrelate prevents downregulation of antiapoptotic protein Bcl-2 and protects the heart against ischemia-reperfusion injury.

    Science.gov (United States)

    Rajesh, Katare Gopalrao; Suzuki, Ryoko; Maeda, Hironori; Murio, Yamamoto; Sasaguri, Shiro

    2006-09-27

    Even though reperfusion is the treatment of choice in patients admitted with acute myocardial infarction, reperfusion itself has been demonstrated to activate various pathological factors especially following procedures of cardiac revascularization. 5-hydroxytryptamine (5HT) is one such factor activated during reperfusion and is known to trigger the post ischemic contractile dysfunction and pathological apoptosis. Here we demonstrate the potential effects of the 5-HT(2)A antagonist sarpogrelate in protecting the myocardium against reperfusion injury of heart. Male Wistar rats weighing between 220 and 240 g were subjected to 30 min left coronary artery (LCA) occlusion and 120 min reperfusion. Sarpogrelate (4 mg/kg) was infused intravenously for 30 min either before LCA occlusion or at reperfusion. Following reperfusion the samples were collected for infarction area, immunohistochemistry, western blotting and myocardial metabolite analysis. Sarpogrelate infusion before ischemia resulted in (a) significant recovery of post ischemic cardiac functions (LVDP, EDP), (b) significant reduction in the infarct size among the risk area after triphenyl tetrazolium chloride staining (p<0.001), (c) decreased tissue water content (p<0.05), (d) well preserved myocardial ATP (p<0.05), (e) reduction in Bcl-2 downregulation and caspase 3 activation and (g) less prevalence of apoptotic cells (3.1+/-0.4% to 15.2+/-0.6%, drug versus control). Treating the rats with sarpogrelate during reperfusion also showed similar results. This study thus demonstrates the protective effects of sarpogrelate and supports the role for 5-HT2A inhibition in preventing the reperfusion injury of the heart. PMID:16876202

  15. The mystery of BCL2 family: Bcl-2 proteins and apoptosis: an update.

    Science.gov (United States)

    Siddiqui, Waseem Ahmad; Ahad, Amjid; Ahsan, Haseeb

    2015-03-01

    Apoptosis is a critically important biological process that plays an essential role in cell fate and homeostasis. An important component of the apoptotic pathway is the family of proteins commonly known as the B cell lymphoma-2 (Bcl-2). The primary role of Bcl-2 family members is the regulation of apoptosis. Although the structure of Bcl-2 family of proteins was reported nearly 10 years ago, however, it still surprises us with its structural and functional complexity and diversity. A number of studies have demonstrated that Bcl-2 family influences many other cellular processes beyond apoptosis which are generally independent of the regulation of apoptosis, suggesting additional roles for Bcl-2. The disruption of the regulation of apoptosis is a causative event in many diseases. Since the Bcl-2 family of proteins is the key regulator of apoptosis, the abnormalities in its function have been implicated in many diseases including cancer, neurodegenerative disorders, ischemia and autoimmune diseases. In the past few years, our understanding of the mechanism of action of Bcl-2 family of proteins and its implications in various pathological conditions has enhanced significantly. The focus of this review is to summarize the current knowledge on the structure and function of Bcl-2 family of proteins in apoptotic cellular processes. A number of drugs have been developed in the past few years that target different Bcl-2 members. The role of Bcl-2 proteins in the pathogenesis of various diseases and their pharmacological significance as effective molecular therapeutic targets is also discussed.

  16. Acidosis Sensing Receptor GPR65 Correlates with Anti-Apoptotic Bcl-2 Family Member Expression in CLL Cells: Potential Implications for the CLL Microenvironment

    OpenAIRE

    Rosko, Ashley E.; McColl, Karen S.; Zhong, Fei; Ryder, Christopher B; Chang, Ming-Jin; Sattar, Abdus; Caimi, Paolo F.; Hill, Brian T; Al-harbi, Sayer; Almasan, Alexandru; Distelhorst, Clark W.

    2014-01-01

    The tumor microenvironment is generally an acidic environment, yet the effect of extracellular acidosis on chronic lymphocytic leukemia (CLL) is not well established. Here we are the first to report that the extracellular acid sensing G-protein coupled receptor, GPR65, is expressed in primary CLL cells where its level correlate strongly with anti-apoptotic Bcl-2 family member levels. GPR65 expression is found normally within the lymphoid lineage and has not been previously reported in CLL. We...

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

    International Nuclear Information System (INIS)

    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

  18. Targeting Antiapoptotic Bcl-2 Family Members with Cell-Permeable BH3 Peptides Induces Apoptosis Signaling, Death in Head, Neck Squamous Cell Carcinoma Cells

    Directory of Open Access Journals (Sweden)

    Rongxiu Li

    2007-10-01

    Full Text Available Head, neck squamous cell carcinomas (HNSCCs are frequently characterized by chemotherapy, radiation resistance, by overexpression of Bcl-XL, an antiapoptotic member of the Bcl-2 protein family. In this report, we examined whether cell-permeable peptides derived from the BH3 domains of proapoptotic Bax, Bad, or Bak could be used to target Bcl-XL and/or Bcl-2 in HNSCC cells, induce apoptotic death in these cells. To render the peptides cell-permeable, Antennapedia (Ant or polyarginine (R8 peptide transduction domain was fused to the amino termini. Fluorescence microscopy of peptide-treated HNSCC cells revealed that the BH3 peptides colocalized with mitochondria, the site of Bcl-XL, Bcl-2 expression. By contrast, a mutant peptide (BaxE BH3 that cannot bind Bcl-XL or Bcl-2 was diffusely localized throughout the cytoplasm. Treatment of three HNSCC cell lines (1483, UM-22A, UM-22B with the wild-type BH3 peptides resulted in loss of viability, induction of apoptosis, as assessed by 3-(4,5-dimethythiazol-2yl-5-(3-carboxymethoxyphenyl-2-(4-sulfophenyl-2H-tetrazolium (MTS assays, annexin V staining. In general, Ant-conjugated peptides were more potent than R8-conjugated peptides, Bad BH3 peptide was typically more potent than Bax BH3 or Bak BH3. Treatment of purified HNSCC mitochondria with BH3 peptides resulted in robust release of cytochrome c. Thus, the relative apoptosis resistance of HNSCC cells is not due to a deficit in this step of the intrinsic, mitochondrialmediated apoptosis pathway. We conclude that cellpermeable BH3 peptides can be used to target Bcl-XL and/or Bcl-2 in HNSCC, that targeting of these proteins may have therapeutic value in the treatment of this disease.

  19. Targeting anti-apoptotic Bcl-2 by AT-101 to increase radiation efficacy: data from in vitro and clinical pharmacokinetic studies in head and neck cancer

    International Nuclear Information System (INIS)

    Pro-survival Bcl-2 family members can promote cancer development and contribute to treatment resistance. Head and neck squamous cell carcinoma (HNSCC) is frequently characterized by overexpression of anti-apoptotic Bcl-2 family members. Increased levels of these anti-apoptotic proteins have been associated with radio- and chemoresistance and poor clinical outcome. Inhibition of anti-apoptotic Bcl-2 family members therefore represents an appealing strategy to overcome resistance to anti-cancer therapies. The aim of this study was to evaluate combined effects of radiation and the pan-Bcl-2 inhibitor AT-101 in HNSCC in vitro. In addition, we determined human plasma levels of AT-101 obtained from a phase I/II trial, and compared these with the effective in vitro concentrations to substantiate therapeutic opportunities. We examined the effect of AT-101, radiation and the combination on apoptosis induction and clonogenic survival in two HNSCC cell lines that express the target proteins. Apoptosis was assessed by bis-benzimide staining to detect morphological nuclear changes and/or by propidium iodide staining and flow-cytometry analysis to quantify sub-diploid apoptotic nuclei. The type of interaction between AT-101 and radiation was evaluated by calculating the Combination Index (CI) and by performing isobolographic analysis. For the pharmacokinetic analysis, plasma AT-101 levels were measured by HPLC in blood samples collected from patients enrolled in our clinical phase I/II study. These patients with locally advanced HNSCC were treated with standard cisplatin-based chemoradiotherapy and received dose-escalating oral AT-101 in a 2-weeks daily schedule every 3 weeks. In vitro results showed that AT-101 enhances radiation-induced apoptosis with CI’s below 1.0, indicating synergy. This effect was sequence-dependent. Clonogenic survival assays demonstrated a radiosensitizing effect with a DEF37 of 1.3 at sub-apoptotic concentrations of AT-101. Pharmacokinetic analysis

  20. BCL-2 family proteins as regulators of mitochondria metabolism.

    Science.gov (United States)

    Gross, Atan

    2016-08-01

    The BCL-2 family proteins are major regulators of apoptosis, and one of their major sites of action are the mitochondria. Mitochondria are the cellular hubs for metabolism and indeed selected BCL-2 family proteins also possess roles related to mitochondria metabolism and dynamics. Here we discuss the link between mitochondrial metabolism/dynamics and the fate of stem cells, with an emphasis on the role of the BID-MTCH2 pair in regulating this link. We also discuss the possibility that BCL-2 family proteins act as metabolic sensors/messengers coming on and off of mitochondria to "sample" the cytosol and provide the mitochondria with up-to-date metabolic information. This article is part of a Special Issue entitled 'EBEC 2016: 19th European Bioenergetics Conference, Riva del Garda, Italy, July 2-6, 2016', edited by Prof. Paolo Bernardi. PMID:26827940

  1. Phosphatidylinositol 3-kinase is essential for kit ligand-mediated survival, whereas interleukin-3 and flt3 ligand induce expression of antiapoptotic Bcl-2 family genes

    DEFF Research Database (Denmark)

    Karlsson, Richard; Engström, Maria; Jönsson, Maria;

    2003-01-01

    affect the survival. We next established if IL-3 and FL activated antiapoptotic Bcl-2 and the related genes Bcl-XL and Mcl-1. By RNA protection assay and Western blot analysis, we show that all three genes are induced by IL-3, whereas FL induces Bcl-2 and to some extent Bcl-XL. Importantly, KL could not...... sustain their expression. Moreover, use of inhibitors implied that IL-3 was mainly exerting its effect on Bcl-2 at the level of transcription. The addition of LY294002 did not affect the expression of Bcl-2 and Bcl-XL, and thus, we conclude that expression of antiapoptotic Bcl-2 family member genes is not...

  2. BCL-2 family proteins as 5-Azacytidine-sensitizing targets and determinants of response in myeloid malignancies

    Science.gov (United States)

    Bogenberger, J M; Kornblau, S M; Pierceall, W E; Lena, R; Chow, D; Shi, C-X; Mantei, J; Ahmann, G; Gonzales, I M; Choudhary, A; Valdez, R; Camoriano, J; Fauble, V; Tiedemann, R E; Qiu, Y H; Coombes, K R; Cardone, M; Braggio, E; Yin, H; Azorsa, D O; Mesa, R A; Stewart, A K; Tibes, R

    2014-01-01

    Synergistic molecular vulnerabilities enhancing hypomethylating agents in myeloid malignancies have remained elusive. RNA-interference drug modifier screens identified antiapoptotic BCL-2 family members as potent 5-Azacytidine-sensitizing targets. In further dissecting BCL-XL, BCL-2 and MCL-1 contribution to 5-Azacytidine activity, siRNA silencing of BCL-XL and MCL-1, but not BCL-2, exhibited variable synergy with 5-Azacytidine in vitro. The BCL-XL, BCL-2 and BCL-w inhibitor ABT-737 sensitized most cell lines more potently compared with the selective BCL-2 inhibitor ABT-199, which synergized with 5-Azacytidine mostly at higher doses. Ex vivo, ABT-737 enhanced 5-Azacytidine activity across primary AML, MDS and MPN specimens. Protein levels of BCL-XL, BCL-2 and MCL-1 in 577 AML patient samples showed overlapping expression across AML FAB subtypes and heterogeneous expression within subtypes, further supporting a concept of dual/multiple BCL-2 family member targeting consistent with RNAi and pharmacologic results. Consequently, silencing of MCL-1 and BCL-XL increased the activity of ABT-199. Functional interrogation of BCL-2 family proteins by BH3 profiling performed on patient samples significantly discriminated clinical response versus resistance to 5-Azacytidine-based therapies. On the basis of these results, we propose a clinical trial of navitoclax (clinical-grade ABT-737) combined with 5-Azacytidine in myeloid malignancies, as well as to prospectively validate BH3 profiling in predicting 5-Azacytidine response. PMID:24451410

  3. BCL-2 family proteins as 5-Azacytidine-sensitizing targets and determinants of response in myeloid malignancies.

    Science.gov (United States)

    Bogenberger, J M; Kornblau, S M; Pierceall, W E; Lena, R; Chow, D; Shi, C-X; Mantei, J; Ahmann, G; Gonzales, I M; Choudhary, A; Valdez, R; Camoriano, J; Fauble, V; Tiedemann, R E; Qiu, Y H; Coombes, K R; Cardone, M; Braggio, E; Yin, H; Azorsa, D O; Mesa, R A; Stewart, A K; Tibes, R

    2014-08-01

    Synergistic molecular vulnerabilities enhancing hypomethylating agents in myeloid malignancies have remained elusive. RNA-interference drug modifier screens identified antiapoptotic BCL-2 family members as potent 5-Azacytidine-sensitizing targets. In further dissecting BCL-XL, BCL-2 and MCL-1 contribution to 5-Azacytidine activity, siRNA silencing of BCL-XL and MCL-1, but not BCL-2, exhibited variable synergy with 5-Azacytidine in vitro. The BCL-XL, BCL-2 and BCL-w inhibitor ABT-737 sensitized most cell lines more potently compared with the selective BCL-2 inhibitor ABT-199, which synergized with 5-Azacytidine mostly at higher doses. Ex vivo, ABT-737 enhanced 5-Azacytidine activity across primary AML, MDS and MPN specimens. Protein levels of BCL-XL, BCL-2 and MCL-1 in 577 AML patient samples showed overlapping expression across AML FAB subtypes and heterogeneous expression within subtypes, further supporting a concept of dual/multiple BCL-2 family member targeting consistent with RNAi and pharmacologic results. Consequently, silencing of MCL-1 and BCL-XL increased the activity of ABT-199. Functional interrogation of BCL-2 family proteins by BH3 profiling performed on patient samples significantly discriminated clinical response versus resistance to 5-Azacytidine-based therapies. On the basis of these results, we propose a clinical trial of navitoclax (clinical-grade ABT-737) combined with 5-Azacytidine in myeloid malignancies, as well as to prospectively validate BH3 profiling in predicting 5-Azacytidine response. PMID:24451410

  4. AT-101, a small molecule inhibitor of anti-apoptotic Bcl-2 family members, activates the SAPK/JNK pathway and enhances radiation-induced apoptosis

    Directory of Open Access Journals (Sweden)

    Rooswinkel Rogier

    2009-10-01

    Full Text Available Abstract Background Gossypol, a naturally occurring polyphenolic compound has been identified as a small molecule inhibitor of anti-apoptotic Bcl-2 family proteins. It induces apoptosis in a wide range of tumor cell lines and enhances chemotherapy- and radiation-induced cytotoxicity both in vitro and in vivo. Bcl-2 and related proteins are important inhibitors of apoptosis and frequently overexpressed in human tumors. Increased levels of these proteins confer radio- and chemoresistance and may be associated with poor prognosis. Consequently, inhibition of the anti-apoptotic functions of Bcl-2 family members represents a promising strategy to overcome resistance to anticancer therapies. Methods We tested the effect of (--gossypol, also denominated as AT-101, radiation and the combination of both on apoptosis induction in human leukemic cells, Jurkat T and U937. Because activation of the SAPK/JNK pathway is important for apoptosis induction by many different stress stimuli, and Bcl-XL is known to inhibit activation of SAPK/JNK, we also investigated the role of this signaling cascade in AT-101-induced apoptosis using a pharmacologic and genetic approach. Results AT-101 induced apoptosis in a time- and dose-dependent fashion, with ED50 values of 1.9 and 2.4 μM in Jurkat T and U937 cells, respectively. Isobolographic analysis revealed a synergistic interaction between AT-101 and radiation, which also appeared to be sequence-dependent. Like radiation, AT-101 activated SAPK/JNK which was blocked by the kinase inhibitor SP600125. In cells overexpressing a dominant-negative mutant of c-Jun, AT-101-induced apoptosis was significantly reduced. Conclusion Our data show that AT-101 strongly enhances radiation-induced apoptosis in human leukemic cells and indicate a requirement for the SAPK/JNK pathway in AT-101-induced apoptosis. This type of apoptosis modulation may overcome treatment resistance and lead to the development of new effective combination

  5. AT-101, a small molecule inhibitor of anti-apoptotic Bcl-2 family members, activates the SAPK/JNK pathway and enhances radiation-induced apoptosis

    International Nuclear Information System (INIS)

    Gossypol, a naturally occurring polyphenolic compound has been identified as a small molecule inhibitor of anti-apoptotic Bcl-2 family proteins. It induces apoptosis in a wide range of tumor cell lines and enhances chemotherapy- and radiation-induced cytotoxicity both in vitro and in vivo. Bcl-2 and related proteins are important inhibitors of apoptosis and frequently overexpressed in human tumors. Increased levels of these proteins confer radio- and chemoresistance and may be associated with poor prognosis. Consequently, inhibition of the anti-apoptotic functions of Bcl-2 family members represents a promising strategy to overcome resistance to anticancer therapies. We tested the effect of (-)-gossypol, also denominated as AT-101, radiation and the combination of both on apoptosis induction in human leukemic cells, Jurkat T and U937. Because activation of the SAPK/JNK pathway is important for apoptosis induction by many different stress stimuli, and Bcl-XL is known to inhibit activation of SAPK/JNK, we also investigated the role of this signaling cascade in AT-101-induced apoptosis using a pharmacologic and genetic approach. AT-101 induced apoptosis in a time- and dose-dependent fashion, with ED50 values of 1.9 and 2.4 μM in Jurkat T and U937 cells, respectively. Isobolographic analysis revealed a synergistic interaction between AT-101 and radiation, which also appeared to be sequence-dependent. Like radiation, AT-101 activated SAPK/JNK which was blocked by the kinase inhibitor SP600125. In cells overexpressing a dominant-negative mutant of c-Jun, AT-101-induced apoptosis was significantly reduced. Our data show that AT-101 strongly enhances radiation-induced apoptosis in human leukemic cells and indicate a requirement for the SAPK/JNK pathway in AT-101-induced apoptosis. This type of apoptosis modulation may overcome treatment resistance and lead to the development of new effective combination therapies

  6. Expression of p53, Bax and Bcl-2 proteins in hepatocytes in non-alcoholic fatty liver disease

    Institute of Scientific and Technical Information of China (English)

    Anatol Panasiuk; Janusz Dzieciol; Bozena Panasiuk; Danuta Prokopowicz

    2006-01-01

    AIM: To analyze the protein expression essential for apoptosis in liver steatosis.METHODS: The expression of proapoptotic proteinsp53, Bax, and antiapoptotic Bcl-2 in hepatocytes with steatosis (SH) and without steatosis (NSH) was evaluated in 84 patients at various stages of non-alcoholic fatty liver disease (NAFLD).RESULTS: Immunohistochemical staining of liver tissue showed the activation of p53 protein in SH and NSH with increased liver steatosis, diminished Bcl-2 and slightly decreased Bax protein. Positive correlation was found between the stage of liver steatosis with p53 expression in SH (r = 0.54, P < 0.01) and NSH (r = 0.49,P < 0.01).The antiapoptotic protein Bcl-2 was diminished together with the advancement of liver steatosis, especially in non-steatosed hepatocytes (r =0.43, P < 001).CONCLUSION: Apoptosis is one of the most important mechanisms leading to hepatocyte elimination in NAFLD. The intensification of inflammation in NAFLD induces proapoptotic protein p53 with the inhibition of antiapoptotic Bcl-2.

  7. 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.

  8. 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.

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

    International Nuclear Information System (INIS)

    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-XL 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.

  10. BCL2 protein expression in follicular lymphomas with t(14;18) chromosomal translocations.

    Science.gov (United States)

    Masir, Noraidah; Campbell, Lisa J; Goff, Lindsey K; Jones, Margaret; Marafioti, Teresa; Cordell, Jacqueline; Clear, Andrew J; Lister, T Andrew; Mason, David Y; Lee, Abigail M

    2009-03-01

    The t(14;18)(q32;q21) chromosomal translocation induces BCL2 protein overexpression in most follicular lymphomas. However the expression of BCL2 is not always homogeneous and may demonstrate a variable degree of heterogeneity. This study analysed BCL2 protein expression pattern in 33 cases of t(14;18)-positive follicular lymphomas using antibodies against two different epitopes (i.e. the widely used antibody BCL2/124 and an alternative antibody E17). 16/33 (49%) cases demonstrated strong BCL2 expression. In 10/33 (30%) cases, BCL2 expression was heterogeneous and in some of these, its loss appeared to be correlated with cell proliferation, as indicated by Ki67 expression. Double immunofluorescence labelling confirmed an inverse BCL2/Ki67 relationship, where in 24/28 (86%) cases cellular expression of BCL2 and Ki67 was mutually exclusive. In addition, seven BCL2 'pseudo-negative' cases were identified in which immunostaining was negative with antibody BCL2/124, but positive with antibody E17. Genomic DNA sequencing of these 'pseudo-negative' cases demonstrated eleven mutations in four cases and nine of these were missense mutations. It can be concluded that in follicular lymphomas, despite carrying the t(14;18) translocations, BCL2 protein expression may be heterogeneous and loss of BCL2 could be related to cell proliferation. Secondly, mutations in translocated BCL2 genes appear to be common and may cause BCL2 pseudo-negative immunostaining. PMID:19120369

  11. Effects of genistein on neuronal apoptosis, and expression of Bcl-2 and Bax proteins in the hippocampus of ovariectomized rats

    Institute of Scientific and Technical Information of China (English)

    Yun Peng; Bo Jiang; Huiling Wu; Ruchun Dai; Liming Tan

    2012-01-01

    Genistein is one of several isoflavones that has a structure similar to 17β-estradiol, has a strong antioxidant effect, and a high affinity to estrogen receptors. At 15 weeks after ovariectomy, the expression of Bcl-2 in the hippocampus of rats decreased and Bax expression increased, with an obvious upregulation of apoptosis. However, intraperitoneal injection of genistein or 17β-estradiol for 15 consecutive weeks from the second day after operation upregulated Bcl-2 protein expression, downregulated Bax protein expression, and attenuated hippocampal neuron apoptosis. Our experimental findings indicate that long-term intervention with genistein can lead to a decrease in apoptosis in hippocampal neurons following ovariectomy, upregulate the expression of Bcl-2, and downregulate the expression of Bax. In addition, genistein and 17β-estradiol play equal anti-apoptotic and neuroprotective roles.

  12. BH4 domain of bcl-2 protein is required for its proangiogenic function under hypoxic condition.

    Science.gov (United States)

    Gabellini, Chiara; De Luca, Teresa; Trisciuoglio, Daniela; Desideri, Marianna; Di Martile, Marta; Passeri, Daniela; Candiloro, Antonio; Biffoni, Mauro; Rizzo, Maria Giulia; Orlandi, Augusto; Del Bufalo, Donatella

    2013-11-01

    Beyond its classical role as apoptosis inhibitor, bcl-2 protein promotes tumor angiogenesis and the removal of N-terminal bcl-2 homology (BH4) domain abrogates bcl-2-induced hypoxia-inducible factor 1 (HIF-1)-mediated vascular endothelial growth factor (VEGF) expression in hypoxic cancer cells. Using M14 human melanoma cell line and its derivative clones stably overexpressing bcl-2 wild-type or deleted of its BH4 domain, we found that conditioned media (CM) from cells expressing BH4-deleted bcl-2 protein showed a reduced capability to increase in vitro human endothelial cells proliferation and differentiation, and in vivo neovascularization compared with CM from cells overexpressing wild-type bcl-2. Moreover, xenografts derived from cells expressing bcl-2 lacking BH4 domain showed a reduction of metastatic potential compared with tumors derived from wild-type bcl-2 transfectants injection. Stably expressing the Flag-tagged N-terminal sequence of bcl-2 protein, encompassing BH4 domain, we found that this domain is sufficient to enhance the proangiogenic HIF-1/VEGF axis under hypoxic condition. Indeed, lacking of BH4 domain abolishes the interaction between bcl-2 and HIF-1α proteins and the capability of exogenous bcl-2 protein to localize in the nucleus. Moreover, when endoplasmic reticulum-targeted bcl-2 protein is overexpressed in cells, this protein lost the capability to synergize with hypoxia to induce the proangiogenic HIF-1/VEGF axis as shown by wild-type bcl-2 protein. These results demonstrate that BH4 domain of bcl-2 is required for the ability of this protein to increase tumor angiogenesis and progression and indicate that bcl-2 nuclear localization may be required for bcl-2-mediated induction of HIF-1/VEGF axis. PMID:23836782

  13. Multimodal Interaction with BCL-2 Family Proteins Underlies the Pro-Apoptotic Activity of PUMA BH3

    OpenAIRE

    Edwards, Amanda L.; Gavathiotis, Evripidis; LaBelle, James L.; Braun, Craig R.; Opoku-Nsiah, Kwadwo A.; Bird, Gregory H.; Walensky, Loren D.

    2013-01-01

    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 analy...

  14. Evaluation of Bax and Bcl-2 Proteins Expression in the Rat Hippocampus due to Childhood Febrile Seizure

    OpenAIRE

    SAEEDI BORUJENI, Mohammad Javad; Hami, Javad; Haghir, Hossein; Rastin, Maryam; Sazegar, Ghasem

    2016-01-01

    Objective Simple Febrile Seizure (SFS) is the most common seizure disorder in childhood, and is frequently described as inoffensive disorder. Nevertheless, there is evidence suggesting the association between neonatal febrile seizures and hippocampal abnormalities in adulthood. This study was conducted at evaluating the hippocampal expression of pro-apoptotic Bax and anti-apoptotic Bcl-2 proteins following SFS induction in rat neonates. Materials & Methods Febrile seizure was modeled by hyper...

  15. BIM (BCL-2 interacting mediator of cell death) SAHB (stabilized α helix of BCL2) not always convinces BAX (BCL-2-associated X protein) for apoptosis.

    Science.gov (United States)

    Verma, Sharad; Goyal, Sukriti; Tyagi, Chetna; Jamal, Salma; Singh, Aditi; Grover, Abhinav

    2016-06-01

    The interaction of BAX (BCL-2-associated X protein) with BIM (BCL-2 interacting mediator of cell death) SAHB (stabilized α helix of BCL2) directly initiates BAX-mediated mitochondrial apoptosis. This molecular dynamics study reveals that BIM SAHB forms a stable complex with BAX but it remains in a non-functional conformation. N terminal of BAX folds towards the core which has been reported exposed in the functional monomer. The α1-α2 loop, which has been reported in open conformation in functional BAX, acquires a closed conformation during the simulation. BH3/α2 remains less exposed as compared to initial structure. The hydrophobic residues of BIM accommodates in the rear pocket of BAX during the simulation. A steep decrease in radius of gyration and solvent accessible surface area (SASA) indicates the complex folding to acquire a more stable but inactive conformation. Further the covariance matrix reveals that the backbone atoms' motions favour the inactive conformation of the complex. This is the first report on the non-functional BAX-BIM SAHB complex by molecular dynamics simulation in the best of our knowledge. PMID:27262527

  16. 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.

  17. The role of the acidity of N-heteroaryl sulfonamides as inhibitors of bcl-2 family protein-protein interactions.

    Science.gov (United States)

    Touré, B Barry; Miller-Moslin, Karen; Yusuff, Naeem; Perez, Lawrence; Doré, Michael; Joud, Carol; Michael, Walter; DiPietro, Lucian; van der Plas, Simon; McEwan, Michael; Lenoir, Francois; Hoe, Madelene; Karki, Rajesh; Springer, Clayton; Sullivan, John; Levine, Kymberly; Fiorilla, Catherine; Xie, Xiaoling; Kulathila, Raviraj; Herlihy, Kara; Porter, Dale; Visser, Michael

    2013-02-14

    Overexpression of the antiapoptotic members of the Bcl-2 family of proteins is commonly associated with cancer cell survival and resistance to chemotherapeutics. Here, we describe the structure-based optimization of a series of N-heteroaryl sulfonamides that demonstrate potent mechanism-based cell death. The role of the acidic nature of the sulfonamide moiety as it relates to potency, solubility, and clearance is examined. This has led to the discovery of novel heterocyclic replacements for the acylsulfonamide core of ABT-737 and ABT-263. PMID:24900652

  18. Study of immunohistochemical demonstration of Bcl-2 protein in ameloblastoma and keratocystic odontogenic tumor

    OpenAIRE

    C S Sindura; Chaitanya Babu; Vijaya Mysorekar; Vinod Kumar

    2013-01-01

    Background: The Bcl-2 (B-cell lymphoma) gene product also known as apoptotic inhibitor is expressed in many normal and tumor tissues. This Bcl-2 gene protects the cell by blocking postmitotic differentiation from apoptosis, thus maintaining the stem cell pool. Objective: To study the expression of Bcl-2 protein in ameloblastoma and keratocystic odontogenic tumor (KCOT) to determine their apoptotic behaviors and to analyze biological nature of KCOT, which has higher proliferative potential and...

  19. Down-Regulation of Bcl-2 Protein Sensitizes NCI 460 Cells to Radiotherapy-Induced Apoptosis

    Institute of Scientific and Technical Information of China (English)

    Dongmei He; Yuan Zhang; Gexiu Liu

    2006-01-01

    OBJECTIVE To determine whether Bcl-2 protein down-regulation can render NCI-460 cells more susceptible to gamma radiation-induced apoptosis by treatment with antisense oligonucleotide (ASODN) against the coding region of Bcl-2 mRNA.METHODS Cell survival was determined using the trypan blue dye exclusion. Expression of the Bcl-2 protein was assayed using immunofluorescence labeling with fluoresce isothiocyanate. Apoptosis was determined by Giemsa staining and flow cytomertry.RESULTS It was found that Bcl-2 ASODN combined with radiation significantly reduced the number of viable cells (P<0.05). There was no difference in cell survival between a nonsense oligodeoxynucleotide/radiation combination and cells treated with radiation alone. Bcl-2 ASODN combined with radiation significantly inhibited expression of the Bcl-2protein in the NCI-H460 cells (P<0.05). Using Giemsa staining, cells treated with Bcl-2 ASODN combined with radiation at 72 h displayed classic apoptotic changes. Apoptotic rates of the NCI-H460 cells treated with Bcl-2 ASODN combined with radiation significantly increased (P<0.05), compared with either a nonsense oligodeoxynucleotide/radiation combination or radiation-treatment cells alone.CONCLUSION ASODN against the coding region of Bcl-2 mRNA increases radiation-induced apoptosis in NCI-H460 cells.

  20. Clinicopathological significance of Bcl-2 and Bax protein expression in human pancreatic cancer

    Institute of Scientific and Technical Information of China (English)

    Ming Dong; Jian-Ping Zhou; Hao Zhang; Ke-Jian Guo; Yu-Lin Tian; Yu-Ting Dong

    2005-01-01

    AIM: To assess the clinicopathological significance of the expression of the apoptosis-inhibitory Bcl-2 protein (pBcl-2) and the apoptosis-promoting Bax protein (pBax) in human invasive ductal carcinomas (IDCs) of the pancreas. METHODS: Fifty-nine surgical specimens of IDCs of the pancreas were stained immunohistochemically to detectpBcl-2 and pBax expressions whose correlation to tumor classification, staging, and prognosis was analyzed by univariate and multivariate analyses. RESULTS: The expression of pBcl-2 and pBax was detected in 21 of 59 (35.6%) and in 29 of 59 (49.2%) patients with IDCs of the pancreas, respectively. Neither pBcl-2 nor pBax alone was correlated to TNM staging and differentiation degree of IDCs of the pancreas according to univariate analysis. By Mantel-Cox test, the median survival time after surgery for pBcl-2(+) and pBcl-2(-) groups were 14.3 and 7.3 mo, respectively (χ2= 9.357, P = 0.002) and that for pBax(+) and pBax(-) groups were 12.9 and 10.2 mo, respectively (χ2= 0.285, P>0.05).Contingency coefficient between pBd-2 and pBax expression was 0.298, indicating that there was correlation between them (χ2= 5.74, P<0.05). The median survival time after surgery for pBd-2(+)pBax(+) and pBcl-2(+)pBax(-) groups were 14.3 and 14.1 mo, respectively, and that for pBcl-2 (-)pBax(+) and pBcl-2(-)pBax(-) groups were 5.9 and 9.9 mo, respectively. There was a significant difference between pBcl-2(+)pBax(+) and pBcl-2(-)pBax(+) (χ2 = 5.06,P<0.05), such was the case for pBcl-2(+)pBax(+) andpBcl-2(-)pBax(-) (χ2= 7.18, P<0.01). Cox proportional hazards model for multivariate analysis was applied, indicating that pBcl-2, TNM staging, age and pBax were high risk factors of post-surgical survival time. CONCLUSION: Both pBcl-2 and pBax have high expression in IDCs of the pancreas, indicating that co-expression of pBcl-2 and pBax is a good indicator of favorable prognosis in IDCs of the pancreas.

  1. Expression of P16 protein and Bcl-2 protein in malignant eyelid tumors

    Institute of Scientific and Technical Information of China (English)

    牛膺筠; 周占宇; 刘夫玲; 王红云

    2002-01-01

    Objective To investigate the relationship between P16 gene (the tumor suppressor gene) and the bcl-2 gene (the apoptosis inhibitor gene) and the incidence and development of malignant eyelid tumors. Methods The streptavidin-biotin-peroxidase complex immunohistochemistry method was used to study the expression of P16 gene and the bcl-2 gene in 96 cases of malignant eyelid tumors. Results Among the 96 cases, there were 40 basal cell carcinomas (BCCs), 33 squamous carcinomas and 23 sebaceous carcinoma, with P16 protein positive (nuclear staining) rates 70%, 54.6% and 56.5%, respectively. The P16 positive rate was negatively correlated with the degree of tumor histological differentiation, and the rate difference between the high differentiated carcinomas was significant (P<0.05). Positive Bcl-2 protein expression was detected in the cytoplasm. All 40 BCC cases were Bcl-2 positive, and nearly all of the tumor cells showed positive cytoplasmic expression, while in the 33 squamous cell carcinoma cases only one showed positive focal reaction, and the staining in the other 32 cases was relatively faint. None of the 23 sebaceous carcinomas expressed Bcl-2. Conclusions The expression of the P16 protein was related to the occurrence and degree of differentiation of malignant eyelid tumors. The overexpression of the Bcl-2 protein suggests that suppression of apoptosis might play a role in the tumorigenesis of BCC.

  2. BCL-2 family proteins as 5-Azacytidine-sensitizing targets and determinants of response in myeloid malignancies

    OpenAIRE

    Bogenberger, J M; Kornblau, S. M.; Pierceall, W E; Lena, R.; Chow, D.; Shi, C-X; Mantei, J; Ahmann, G; Gonzales, I M; A. Choudhary; R. Valdez; Camoriano, J; Fauble, V; Tiedemann, R E; Qiu, Y H

    2014-01-01

    Synergistic molecular vulnerabilities enhancing hypomethylating agents in myeloid malignancies have remained elusive. RNA-interference drug modifier screens identified antiapoptotic BCL-2 family members as potent 5-Azacytidine-sensitizing targets. In further dissecting BCL-XL, BCL-2 and MCL-1 contribution to 5-Azacytidine activity, siRNA silencing of BCL-XL and MCL-1, but not BCL-2, exhibited variable synergy with 5-Azacytidine in vitro. The BCL-XL, BCL-2 and BCL-w inhibitor ABT-737 sensitize...

  3. Sheeppox virus SPPV14 encodes a Bcl-2-like cell death inhibitor that counters a distinct set of mammalian proapoptotic proteins.

    Science.gov (United States)

    Okamoto, Toru; Campbell, Stephanie; Mehta, Ninad; Thibault, John; Colman, Peter M; Barry, Michele; Huang, David C S; Kvansakul, Marc

    2012-11-01

    Many viruses express inhibitors of programmed cell death (apoptosis), thereby countering host defenses that would otherwise rapidly clear infected cells. To counter this, viruses such as adenoviruses and herpesviruses express recognizable homologs of the mammalian prosurvival protein Bcl-2. In contrast, the majority of poxviruses lack viral Bcl-2 (vBcl-2) homologs that are readily identified by sequence similarities. One such virus, myxoma virus, which is the causative agent of myxomatosis, expresses a virulence factor that is a potent inhibitor of apoptosis. In spite of the scant sequence similarity to Bcl-2, myxoma virus M11L adopts an almost identical 3-dimensional fold. We used M11L as bait in a sequence similarity search for other Bcl-2-like proteins and identified six putative vBcl-2 proteins from poxviruses. Some are potent inhibitors of apoptosis, in particular sheeppox virus SPPV14, which inhibited cell death induced by multiple agents. Importantly, SPPV14 compensated for the loss of antiapoptotic F1L in vaccinia virus and acts to directly counter the cell death mediators Bax and Bak. SPPV14 also engages a unique subset of the death-promoting BH3-only ligands, including Bim, Puma, Bmf, and Hrk. This suggests that SPPV14 may have been selected for specific biological roles as a virulence factor for sheeppox virus. PMID:22896610

  4. Increased ratio of anti-apoptotic to pro-apoptotic Bcl2 gene-family members in lithium-responders one month after treatment initiation

    Directory of Open Access Journals (Sweden)

    Lowthert Lori

    2012-09-01

    Full Text Available Abstract Background Lithium is considered by many as the gold standard medication in the management of bipolar disorder (BD. However, the clinical response to lithium is heterogeneous, and the molecular basis for this difference in response is unknown. In the present study, we sought to determine how the peripheral blood gene expression profiles of patients with bipolar disorder (BD changed over time following intitiation of treatment with lithium, and whether differences in those profiles over time were related to the clinical response. Methods Illumina Sentrix Beadchip (Human-6v2 microarrays containing > 48,000 transcript probes were used to measure levels of expression of gene-expression in peripheral blood from 20 depressed subjects with BD prior to and every two weeks during 8 weeks of open-label treatment with lithium. Changes in gene-expression were compared between treatment responders (defined as a decrease in the Hamilton Depression Rating Scale of 50% or more and non-responders. Pathway analysis was conducted using GeneGO Metacore software. Results 127 genes showed a differential response in responders vs. non-responders. Pathway analysis showed that regulation of apoptosis was the most significantly affected pathway among these genes. Closer examination of the time-course of changes among BCL2 related genes showed that in lithium-responders, one month after starting treatment with lithium, several anti-apoptotic genes including Bcl2 and insulin receptor substrate 2 (IRS2 were up-regulated, while pro-apoptotic genes, including BCL2-antagonist/killer 1 (BAK1 and BCL2-associated agonist of cell death (BAD, were down-regulated. In contrast, in lithium non-responders, BCL2 and IRS2 were down-regulated, while BAK1 and BAD up-regulated at the one-month time-point. Conclusions These results suggest that differential changes in the balance of pro- and anti- apoptotic gene-expression following treatment with lithium may explain some of

  5. Increase of bcl-2 Protein Expression in Aggressive Basal Cell Carcinoma of Head and Neck

    OpenAIRE

    Cláudia CAZAL; ELY Mariana Roesch; Ana Paula Veras SOBRAL; Wilton Wilney Nascimento PADILHA

    2006-01-01

    Objective: The aim of this study was to verify the bcl-2 protein expression in 22 cutaneous basal cell carcinomas (BCC) of the head and neck, and to compare it with its aggressive behavior. Method: Tumors were histologically classified in non-aggressive (BCC 1) and aggressive (BCC 2) and then submitted to the immunohistochemistry technique with the streptavidin-biotin peroxidase method using the anti-bcl-2 antibody. Results: After proceeding to morphological analysis, sixteen tumors (72.7%) w...

  6. Bcl-2蛋白家族与运动%Bcl-2 Protein Family Members and Exercises

    Institute of Scientific and Technical Information of China (English)

    吴环成; 贺道远

    2004-01-01

    Bcl-2蛋白家族根据其在细胞凋亡中的作用,分为抑凋亡蛋白和促凋亡蛋白.在骨骼肌细胞和心肌细胞内,Bcl-2家族成员之间形成二聚体,调节细胞是否进入凋亡程序.不同强度的运动对骨骼肌、心肌和淋巴细胞凋亡的影响不尽相同.

  7. Immunohistochemical localization of Bcl-2 and Bax proteins in in situ and invasive duct breast carcinomas.

    Science.gov (United States)

    Kapucuoglu, N; Losi, L; Eusebi, V

    1997-01-01

    Bcl-2 and Bax proteins are coded by a family of genes that take part in the manteinance of the balance between cell proliferation rate and programmed cell death in multicellular organisms. The Bax gene acts as promoter of cell death by opposing the death protector effect of the Bcl-2 gene. Expression of the Bcl-2 and Bax proteins has been investigated in 58 cases of duct carcinoma in situ (DCIS) and duct invasive and invasive lobular carcinomas (IC) of the breast. While both proteins were expressed at the same time in normal and benign epithelium, different staining patterns were observed according to the degree of differentiation of the neoplastic epithelium. In well-differentiated DCIS and grade I IC there was a predominance of Bcl-2 protein staining. Grade II lesions co-expressed both proteins. Poorly differentiated DCIS displayed a predominantly Bax protein staining pattern. Therefore, it appears that Bax protein expression, especially in DCIS, relates to more aggressive neoplasms while Bcl-2 protein expression is associated with less aggressive malignant lesions.

  8. Orphan Nuclear Receptor NR4A1 Binds a Novel Protein Interaction Site on Anti-apoptotic B Cell Lymphoma Gene 2 Family Proteins.

    Science.gov (United States)

    Godoi, Paulo H C; Wilkie-Grantham, Rachel P; Hishiki, Asami; Sano, Renata; Matsuzawa, Yasuko; Yanagi, Hiroko; Munte, Claudia E; Chen, Ya; Yao, Yong; Marassi, Francesca M; Kalbitzer, Hans R; Matsuzawa, Shu-Ichi; Reed, John C

    2016-07-01

    B cell lymphoma gene 2 (Bcl-2) family proteins are key regulators of programmed cell death and important targets for drug discovery. Pro-apoptotic and anti-apoptotic Bcl-2 family proteins reciprocally modulate their activities in large part through protein interactions involving a motif known as BH3 (Bcl-2 homology 3). Nur77 is an orphan member of the nuclear receptor family that lacks a BH3 domain but nevertheless binds certain anti-apoptotic Bcl-2 family proteins (Bcl-2, Bfl-1, and Bcl-B), modulating their effects on apoptosis and autophagy. We used a combination of NMR spectroscopy-based methods, mutagenesis, and functional studies to define the interaction site of a Nur77 peptide on anti-apoptotic Bcl-2 family proteins and reveal a novel interaction surface. Nur77 binds adjacent to the BH3 peptide-binding crevice, suggesting the possibility of cross-talk between these discrete binding sites. Mutagenesis of residues lining the identified interaction site on Bcl-B negated the interaction with Nur77 protein in cells and prevented Nur77-mediated modulation of apoptosis and autophagy. The findings establish a new protein interaction site with the potential to modulate the apoptosis and autophagy mechanisms governed by Bcl-2 family proteins. PMID:27129202

  9. Anti-apoptotic activity of caffeic acid, ellagic acid and ferulic acid in normal human peripheral blood mononuclear cells: a Bcl-2 independent mechanism.

    Science.gov (United States)

    Khanduja, Krishan Lal; Avti, Pramod Kumar; Kumar, Surender; Mittal, Nidhi; Sohi, Kiranjit Kaur; Pathak, Chander Mohan

    2006-02-01

    Polyphenols have been shown to induce apoptosis in a variety of tumor cells including leukemia both in vitro and in vivo. However, their action on normal human peripheral blood mononuclear cells (PBMCs) during oxidative stress remains to be explored. In this study, we have evaluated the anti-apoptotic and radical scavenging activities of dietary phenolics, namely caffeic acid (CA), ellagic acid (EA) and ferulic acid (FA). H2O2-induced apoptosis in normal human PBMCs was assayed by phosphotidylserine externalization, nucleosomal damage and DNA fragmentation. Incubation of PBMCs with 5 mM H2O2 led to increased Annexin-V binding to externalized phosphatidyl serine (PS), an event of pre-apoptotic stage of the cell. Peripheral blood mononuclear cells pretreated with phenolics could resist H2O2-induced apoptotic damage. Caffeic acid (60 and 120 microM) and EA (100 and 200 microM) caused no change in externalization of PS, whereas FA (100 and 200 microM) increased externalization of PS in PBMCs treated with H2O2. The effects of phenolics were abolished to a large extent by culturing the PBMCs for 24 h after washing the phenolics from the medium. Inhibitory activities of these phenolics on lipid peroxidation were in the order of EABcl-2 expression in PBMCs. In conclusion, the anti-apoptotic effect of EA, CA and FA in PBMCs seems to be through the Bcl-2 independent mechanism. PMID:16459021

  10. Fibroblast Growth Factor-2 and the HIV-1 Tat Protein Synergize in Promoting Bcl-2 Expression and Preventing Endothelial Cell Apoptosis: Implications for the Pathogenesis of AIDS-Associated Kaposi's Sarcoma

    Directory of Open Access Journals (Sweden)

    Cecilia Sgadari

    2011-01-01

    Here we show that the development of angioproliferative lesions promoted in mice by combined Tat and FGF-2 associates with an increase in the levels of expression of the antiapoptotic Bcl-2 protein. Upregulation of Bcl-2 expression by combined FGF-2 and Tat occurs also in vitro, and this protects human primary endothelial cells from programmed cell death. As Bcl-2 is expressed in human KS lesions in a fashion paralleling the progression of the disease, these findings suggest a molecular mechanism by which Tat and FGF-2 cooperate in KS maintenance and progression in HIV-infected individuals.

  11. The Significance and Correlation of SODD and Bcl-2 Protein Expression in Acute Leukemia of Children

    Institute of Scientific and Technical Information of China (English)

    Hongfang Tao; Qun Hu; Liuqing Zhang; Aiguo Liu; Shuangyou Liu; Ying Hu

    2006-01-01

    OBJECTIVE To explore the expression of SODD and bcl-2 proteins in bone marrow cells of children with acute leukemia (AL), and to examine the relationship of their expression with the classification, clinical features,therapeutic effect and prognosis for AL patients.METHODS Using the SABC immunohistochemical staining method, the expression of SODD and bcl-2 proteins in the bone marrow cells of 86 AL cases was determined. The patients were studied based on the following groups: 1) a first-visiting group; 2) a refractory-relapse group(some patients were sensitive to therapy but then suffered a recurrence);3) a complete-remission group (CR); 4) a high risk (HR) and 5) standard risk (SR) group; 6) a control group of patients with non-hematological diseases.RESULTS The positive rates of SODD and bcl-2 expression in the firstvisit, refractory-relapse and CR groups were significantly higher (P<0.05)compared to the control group. There was no significant difference in the expression of SODD or bcl-2 proteins between an acute lymphoblastic leukemia (ALL) group and acute nonlymphoblastic leukemia (ANLL)group (t=1.874, t=1.583, P>0.05). The positive rates of SODD and bcl-2expression in the patients who developed complete remission after chemotherapy were significantly lower (t=2.054, t=2.703, P<0.05) compared to the first-visit pediatric patients. The expression of the SODD protein in the refractory-relapse group was notably higher compared to the group treated initially (t=-1.081, P<0.05). A high expression of the bcl-2 protein was found in both the first-visit and refractory-relapse groups, with no significant difference found between the two groups (t=-1.196, P>0.05), whereas the percentage of bcl-2 positive cells in the refractory-relapse group (45%~87%) was significantly higher compared to the first-visit group (5%~62%). The positive expression of the SODD and bcl-2 proteins in the high-risk (HR) group were both significantly higher than the SR group (t=-3

  12. Removal of the BH4 Domain from Bcl-2 Protein Triggers an Autophagic Process that Impairs Tumor Growth12

    Science.gov (United States)

    Trisciuoglio, Daniela; De Luca, Teresa; Desideri, Marianna; Passeri, Daniela; Gabellini, Chiara; Scarpino, Stefania; Liang, Chengyu; Orlandi, Augusto; Del Bufalo, Donatella

    2013-01-01

    Here, we show that forced expression of a B-cell lymphoma 2 (bcl-2) protein lacking residues 1 to 36 at the N-terminal, including the entire Bcl-2 homology 4 (BH4) domain, determines reduction of in vitro and in vivo human melanoma growth. Noteworthy, melanoma cells in vivo exhibit markedly increased autophagy, as response to expression of bcl-2 protein deleted of its BH4 domain. This observation led to the identification of a novel gain of function for bcl-2 protein lacking the BH4 domain. In particular, upon different autophagic stimuli in vitro, overexpression of bcl-2 protein deleted of BH4 domain induces autophagosome accumulation, conversion of microtubule-associated protein 1 light chain 3B-II, reduced expression of p62/SQSTM1 protein, and thereby enhanced autophagic flux. The relevance of Beclin-1 is evidenced by the fact that 1) the autophagy-promoting and growth-inhibiting properties are partially rescued by Beclin-1 knockdown in cells expressing bcl-2 protein lacking the BH4 domain, 2) Beclin-1 only interacts with wild-type but not with deleted bcl-2, and 3) BH4 domain removal from bcl-2 protein does not influence in vitro and in vivo growth of tumor cells expressing low levels of endogenous Beclin-1. These results provide new insight into molecular mechanism of bcl-2 functions and represent a rationale for the development of agents interfering with the BH4 domain of bcl-2 protein. PMID:23479509

  13. Removal of the BH4 Domain from Bcl-2 Protein Triggers an Autophagic Process that Impairs Tumor Growth

    Directory of Open Access Journals (Sweden)

    Daniela Trisciuoglio

    2013-03-01

    Full Text Available Here, we show that forced expression of a B-cell lymphoma 2 (bcl-2 protein lacking residues 1 to 36 at the N-terminal, including the entire Bcl-2 homology 4 (BH4 domain, determines reduction of in vitro and in vivo human melanoma growth. Noteworthy, melanoma cells in vivo exhibit markedly increased autophagy, as response to expression of bcl-2 protein deleted of its BH4 domain. This observation led to the identification of a novel gain of function for bcl-2 protein lacking the BH4 domain. In particular, upon different autophagic stimuli in vitro, overexpression of bcl-2 protein deleted of BH4 domain induces autophagosome accumulation, conversion of microtubule-associated protein 1 light chain 3B-II, reduced expression of p62/SQSTM1 protein, and thereby enhanced autophagic flux. The relevance of Beclin-1 is evidenced by the fact that 1 the autophagy-promoting and growth-inhibiting properties are partially rescued by Beclin-1 knockdown in cells expressing bcl-2 protein lacking the BH4 domain, 2 Beclin-1 only interacts with wild-type but not with deleted bcl-2, and 3 BH4 domain removal from bcl-2 protein does not influence in vitro and in vivo growth of tumor cells expressing low levels of endogenous Beclin-1. These results provide new insight into molecular mechanism of bcl-2 functions and represent a rationale for the development of agents interfering with the BH4 domain of bcl-2 protein.

  14. Removal of the BH4 domain from Bcl-2 protein triggers an autophagic process that impairs tumor growth.

    Science.gov (United States)

    Trisciuoglio, Daniela; De Luca, Teresa; Desideri, Marianna; Passeri, Daniela; Gabellini, Chiara; Scarpino, Stefania; Liang, Chengyu; Orlandi, Augusto; Del Bufalo, Donatella

    2013-03-01

    Here, we show that forced expression of a B-cell lymphoma 2 (bcl-2) protein lacking residues 1 to 36 at the N-terminal, including the entire Bcl-2 homology 4 (BH4) domain, determines reduction of in vitro and in vivo human melanoma growth. Noteworthy, melanoma cells in vivo exhibit markedly increased autophagy, as response to expression of bcl-2 protein deleted of its BH4 domain. This observation led to the identification of a novel gain of function for bcl-2 protein lacking the BH4 domain. In particular, upon different autophagic stimuli in vitro, overexpression of bcl-2 protein deleted of BH4 domain induces autophagosome accumulation, conversion of microtubule-associated protein 1 light chain 3B-II, reduced expression of p62/SQSTM1 protein, and thereby enhanced autophagic flux. The relevance of Beclin-1 is evidenced by the fact that 1) the autophagy-promoting and growth-inhibiting properties are partially rescued by Beclin-1 knockdown in cells expressing bcl-2 protein lacking the BH4 domain, 2) Beclin-1 only interacts with wild-type but not with deleted bcl-2, and 3) BH4 domain removal from bcl-2 protein does not influence in vitro and in vivo growth of tumor cells expressing low levels of endogenous Beclin-1. These results provide new insight into molecular mechanism of bcl-2 functions and represent a rationale for the development of agents interfering with the BH4 domain of bcl-2 protein. PMID:23479509

  15. Increase of bcl-2 Protein Expression in Aggressive Basal Cell Carcinoma of Head and Neck

    Directory of Open Access Journals (Sweden)

    Cláudia CAZAL

    2006-09-01

    Full Text Available Objective: The aim of this study was to verify the bcl-2 protein expression in 22 cutaneous basal cell carcinomas (BCC of the head and neck, and to compare it with its aggressive behavior. Method: Tumors were histologically classified in non-aggressive (BCC 1 and aggressive (BCC 2 and then submitted to the immunohistochemistry technique with the streptavidin-biotin peroxidase method using the anti-bcl-2 antibody. Results: After proceeding to morphological analysis, sixteen tumors (72.7% were considered aggressive and six (27.3% non-aggressive. Immunohistochemistry analysis showed that thirteen (59.1% lesions were positive staining and nine (40.9% were negative to the bcl-2 protein. Considering the positive lesions, 12 (92.3% were aggressive and one (7.7% non-aggressive. The relation between bcl-2 protein staining and the tumor aggressiveness was statistically significant (p<0.05 - Fisher's exact Test. Conclusion: The results suggest a relationship between the bcl-2 protein expression and the histological aggressiveness grade in the BCC of the head and neck group studied may exist.

  16. Study of immunohistochemical demonstration of Bcl-2 protein in ameloblastoma and keratocystic odontogenic tumor

    Directory of Open Access Journals (Sweden)

    C S Sindura

    2013-01-01

    Full Text Available Background: The Bcl-2 (B-cell lymphoma gene product also known as apoptotic inhibitor is expressed in many normal and tumor tissues. This Bcl-2 gene protects the cell by blocking postmitotic differentiation from apoptosis, thus maintaining the stem cell pool. Objective: To study the expression of Bcl-2 protein in ameloblastoma and keratocystic odontogenic tumor (KCOT to determine their apoptotic behaviors and to analyze biological nature of KCOT, which has higher proliferative potential and aggressive clinical behavior like odontogenic tumors. Materials and Methods: Formalin-fixed paraffin sections of ameloblastoma (n = 20 and KCOT (n = 20 are considered for immunohistochemical analysis using monoclonal antibody against antihuman Bcl-2 oncoprotein. Lymphomas (n = 3 were used as controls. Statistical Analysis: The statistical analysis was performed using software package of social science version 16.The data were analyzed using Chi-square test and Student′s t test. In all the above tests, P < 0.05 was accepted as statistically significant. Results: The positive ratio of Bcl-2 was 85% (17/20 in ameloblastoma, 85% (17/20 in KCOT and 100% (3/3 in lymphomas. Bcl-2 was expressed in peripheral cells and few scattered cells of stellate reticulum in ameloblastoma. KCOT showed strong positivity for Bcl-2 mainly in the basal layer. Interpretation and Conclusion: The present study demonstrates the aggressive nature of KCOT and intrinsic growth potential of its lining epithelium. This study clearly demonstrates that KCOT like ameloblastoma demonstrates aggressive clinical and noticeable invasive behavior. Therefore, it is now considered as no longer a developmental cyst but as odontogenic tumor.

  17. Affinity purification-mass spectrometry analysis of bcl-2 interactome identified SLIRP as a novel interacting protein.

    Science.gov (United States)

    Trisciuoglio, D; Desideri, M; Farini, V; De Luca, T; Di Martile, M; Tupone, M G; Urbani, A; D'Aguanno, S; Del Bufalo, D

    2016-01-01

    Members of the bcl-2 protein family share regions of sequence similarity, the bcl-2 homology (BH) domains. Bcl-2, the most studied member of this family, has four BH domains, BH1-4, and has a critical role in resistance to antineoplastic drugs by regulating the mitochondrial apoptotic pathway. Moreover, it is also involved in other relevant cellular processes such as tumor progression, angiogenesis and autophagy. Deciphering the network of bcl-2-interacting factors should provide a critical advance in understanding the different functions of bcl-2. Here, we characterized bcl-2 interactome by mass spectrometry in human lung adenocarcinoma cells. In silico functional analysis associated most part of the identified proteins to mitochondrial functions. Among them we identified SRA stem-loop interacting RNA-binding protein, SLIRP, a mitochondrial protein with a relevant role in regulating mitochondrial messenger RNA (mRNA) homeostasis. We validated bcl-2/SLIRP interaction by immunoprecipitation and immunofluorescence experiments in cancer cell lines from different histotypes. We showed that, although SLIRP is not involved in mediating bcl-2 ability to protect from apoptosis and oxidative damage, bcl-2 binds and stabilizes SLIRP protein and regulates mitochondrial mRNA levels. Moreover, we demonstrated that the BH4 domain of bcl-2 has a role in maintaining this binding. PMID:26866271

  18. Glutathione and Bcl-2 targeting facilitates elimination by chemoradiotherapy of human A375 melanoma xenografts overexpressing bcl-xl, bcl-2, and mcl-1

    Directory of Open Access Journals (Sweden)

    Mena Salvador

    2012-01-01

    Full Text Available Abstract Background Bcl-2 is believed to contribute to melanoma chemoresistance. However, expression of Bcl-2 proteins may be different among melanomas. Thus correlations among expression of Bcl-2-related proteins and in vivo melanoma progression, and resistance to combination therapies, was investigated. Methods Human A375 melanoma was injected s.c. into immunodeficient nude mice. Protein expression was studied in tumor samples obtained by laser microdisection. Transfection of siRNA or ectopic overexpression were applied to manipulate proteins which are up- or down-regulated, preferentially, during melanoma progression. Anti-bcl-2 antisense oligonucleotides and chemoradiotherapy (glutathione-depleting agents, paclitaxel protein-binding particles, daunorubicin, X rays were administered in combination. Results In vivo A375 cells down-regulated pro-apoptotic bax expression; and up-regulated anti-apoptotic bcl-2, bcl-xl, and mcl-1, however only Bcl-2 appeared critical for long-term tumor cell survival and progression in vivo. Reduction of Bcl-2, combined with partial therapies, decreased melanoma growth. But only Bcl-2 targeting plus the full combination of chemoradiotherapy eradicated A375 melanoma, and led to long-term survival (> 120 days without recurrence in 80% of mice. Tumor regression was not due to immune stimulation. Hematology and clinical chemistry data were within accepted clinical toxicities. Conclusion Strategies to target Bcl-2, may increase the effectiveness of antitumor therapies against melanomas overexpressing Bcl-2 and likely other Bcl-2-related antiapoptotic proteins.

  19. Protection of Bcl-2 by salubrinal

    OpenAIRE

    Kessel, David

    2006-01-01

    The drug salubrinal has been identified as an inhibitor of phosphatases that act on the eukaryotic translation initiation factor 2 subunit (eIF2α). The resulting maintenance of protein phosphorylation results in enhanced protection from the adverse effects of initiators of the unfolded protein response. We found that salubrinal can also interact with the anti-apoptotic protein Bcl-2, inhibiting binding of the non-peptidic antagonist HA14-1 and of a porphycene that can catalyze Bcl-2 photodama...

  20. CO-EXPRESSIONS OF SURVIVIN GENE,BCL-2 AND BAX PROTEINS IN OVARIAN CARCINOMA

    Institute of Scientific and Technical Information of China (English)

    林蓓; 张淑兰; 赵长清

    2004-01-01

    Objective To characterize the cellular properties of ovarian cancer, we examined the correlation between the expression of apoptosis-related gene survivin and those of Bcl-2 and Bar proteins. Methods Expressions of survivin mRNA, and Bcl-2 and Bax proteins in 35 cases of ovarian carcinoma, 10 cases of borderline carcinoma, 10 cases of benign tumors and 10 cases of normal tissue were evaluated by reverse transcription polymerase chain reaction (RT-PCR) and immunohistochemistry SABC method, respectively. Results Expression of survivin gene was detected in a significantly greater proportion in ovarian carcinoma and borderline carcinoma than those in benign tumors and normal tissues. Although there was no relationship between expression of survivin gene and FIGO stage, histologic grade, pathological type and lymphatic metastasis, expressions of Bcl-2 and Bar proteins were positively and negatively correlated with that of survivin gene, respectively. Conclusion Survivin may play an important role in pathogenesis of ovarian carcinoma, with a synergistic role of apoptosis-related gene Bcl-2protein and an antagonistic role of Bax protein in formation and progression of ovarian carcinoma.

  1. Dioscin-induced apoptosis of human LNCaP prostate carcinoma cells through activation of caspase-3 and modulation of Bcl-2 protein family.

    Science.gov (United States)

    Chen, Jing; Li, Hui-min; Zhang, Xue-nong; Xiong, Chao-mei; Ruan, Jin-lan

    2014-02-01

    Dioscin is a natural steroid saponin derived from several plants, showing potent anti-cancer effect against a variety of tumor cell lines. In the present study, we investigated the anti-cancer activity of dioscin against human LNCaP cells, and evaluated the possible mechanism involved in its antineoplastic action. It was found that dioscin (1, 2 and 4 μmol/L) could significantly inhibit the viability of LNCaP cells in a time- and concentration-dependent manner. Flow cytometry revealed that the apoptosis rate was increased after treatment of LNCaP cells with dioscin for 24 h, indicating that apoptosis was an important mechanism by which dioscin inhibited cancer. Western blotting was employed to detect the expression of caspase-3, Bcl-2 and Bax in LNCaP cells. The expression of cleaved caspase-3 was significantly increased, and meanwhile procaspase-3 was markedly decreased. The expression of anti-apoptotic protein Bcl-2 was down-regulated, whereas the pro-apoptotic protein Bax was up-regulated. Moreover, the Bcl-2/Bax ratio was drastically decreased. These results suggested that dioscin possessed potential anti-tumor activity in human LNCaP cells through the apoptosis pathway, which might be associated with caspase-3 and Bcl-2 protein family. PMID:24496691

  2. Removal of the BH4 Domain from Bcl-2 Protein Triggers an Autophagic Process that Impairs Tumor Growth12

    OpenAIRE

    Trisciuoglio, Daniela; De Luca, Teresa; Desideri, Marianna; Passeri, Daniela; Gabellini, Chiara; Scarpino, Stefania; Liang, Chengyu; Orlandi, Augusto; Del Bufalo, Donatella

    2013-01-01

    Here, we show that forced expression of a B-cell lymphoma 2 (bcl-2) protein lacking residues 1 to 36 at the N-terminal, including the entire Bcl-2 homology 4 (BH4) domain, determines reduction of in vitro and in vivo human melanoma growth. Noteworthy, melanoma cells in vivo exhibit markedly increased autophagy, as response to expression of bcl-2 protein deleted of its BH4 domain. This observation led to the identification of a novel gain of function for bcl-2 protein lacking the BH4 domain. I...

  3. Effects of Nerve Growth Factor on Bcl-2 Protein after Spinal Cord Injury in Rats

    Institute of Scientific and Technical Information of China (English)

    汤长华; 曹晓建; 王道新

    2002-01-01

    Objective To explore the protective mechanisms of nerve growth factor( NGF) ou spinal cord injury(SCI) and provide theoretical basis for its clinical application. MethodsThe SCI of Wistar rats was done by Allens weight dropping way by a 10 g × 2.5 cm impact on theposterior of spinal cord T8 NGF ( 3 g/L, 20d) or normal saline was injected to treatment group ratsthrough catheter into subarachnoid space at 0,2,4,8,12 and 24 h after SCI. The expression of bcl-2 protein levels in rat spinal cord was detected by immunohistoclemistry. Results The strong expres-sion sequence of bcl-2 protein was found in spinal cord of normal rat group. The levels of bcl-2 pro-tein after SCI in NGF treatment group increased more significantly than those in normal saline treatmentgroup (P<0. 01). Conclusion NGF could protect injured spinal cord by stimulating bcl-2 pro-tein expression and suppressing apoptosis after SCI.

  4. Bid, a widely expressed proapoptotic protein of the Bcl-2 family, displays lipid transfer activity

    DEFF Research Database (Denmark)

    Esposti, M D; Erler, Janine Terra; Hickman, J A;

    2001-01-01

    Bid is an abundant proapoptotic protein of the Bcl-2 family that is crucial for the induction of death receptor-mediated apoptosis in primary tissues such as liver. Bid action has been proposed to involve the relocation of its truncated form, tBid, to mitochondria to facilitate the release of apo...

  5. 吗啡成瘾时脑内Fas、Bcl-2和Caspase-3蛋白表达的改变%Changes of Fas, Bcl-2 and Caspase-3 protein in rat brain during morphine addiction

    Institute of Scientific and Technical Information of China (English)

    刘立伟; 王新华; 傅舒昆; 吴青华; 傅强

    2012-01-01

    目的 观察吗啡成瘾时脑细胞中凋亡相关蛋白Fas、Caspase-3和Bcl-2表达的改变.方法 将48只体质量为190~210 g的成年SD大鼠随机分为3组:吗啡依赖组、吗啡戒断组和对照组,每组16只.依据药物递增原则,依赖组和戒断组大鼠腹腔内给予吗啡13d,建立吗啡成瘾模型.戒断组大鼠在成瘾后腹腔内注射纳洛酮5 mg/kg,诱导戒断30 min.对照组大鼠在相同的治疗时间腹腔内注射生理盐水.应用免疫组织化学、蛋白印迹分析方法检测大鼠海马区Fas、Bcl-2和Caspase-3蛋白的表达.结果 与对照组比较,吗啡依赖组和戒断组大鼠海马区Fas和Caspase-3的表达增加(P<0.01),而Bcl-2的表达降低(P<0.01).结论 长期应用吗啡可通过Fas、Caspase-3表达的增加和Bcl-2表达的降低诱发脑细胞异常凋亡,这可能是阿片类药物引起神经损害的机制之一.%Objective To investigate the changes of apoptosis-related proteins Fas,Caspase-3 and Bcl-2 expression in rat brain during morphine addiction. Methods A total of 48 adult male Sprague-Dawley rats, weighing 190-210 g, were randomly divided into 3 groups (n=16): chronic morphine-dependent group, chronic morphine-abstinent group and control group. The rats in dependent group and abstinent group were chronically treated with morphine for 13 days to establish morphine dependent model. In the abstinent group, the withdrawal syndromes were induced with intraperitoneal injection of naloxone 5 mg/kg for 30 min. The control group was injected with normal saline. Immunohistochemistry and Western blotting analysis were used to examine the expression of Fas, Bcl-2 and Caspase-3 proteins. Results Compared with the control group, the other two groups had significantly increased expression of Fas and Caspase-3 (PBcl-2 (P< 0.01) in the hippocampal synapse. Conclusion It is demonstrated that long term use of morphine can promote abnormal

  6. Endothelium Expression of Bcl-2 Is Essential for Normal and Pathological Ocular Vascularization.

    Directory of Open Access Journals (Sweden)

    Ismail S Zaitoun

    Full Text Available Bcl-2 is an anti-apoptotic protein with important roles in vascular homeostasis and angiogenesis. Mice globally lacking Bcl-2 (Bcl-2 -/- are small in stature and succumb to renal failure shortly after weaning as a result of renal hypoplasia/cystic dysplasia. We have shown that Bcl-2 -/- mice displayed attenuated retinal vascular development and neovascularization. In vitro studies indicated that in addition to modulating apoptosis, Bcl-2 expression also impacts endothelial and epithelial cell adhesion, migration and extracellular matrix production. However, studies delineating the cell autonomous role Bcl-2 expression plays in the endothelium during vascular development, pruning and remodeling, and neovascularization are lacking. Here we generated mice carrying a conditional Bcl-2 allele (Bcl-2Flox/Flox and VE-cadherin-cre (Bcl-2EC mice. Bcl-2EC mice were of normal stature and lifespan and displayed some but not all of the retinal vascular defects previously observed in global Bcl-2 deficient mice. Bcl-2EC mice had decreased numbers of endothelial cells, decreased retinal arteries and premature primary branching of the retinal vasculature, but unlike the global knockout mice, spreading of the retinal superficial vascular layer proceeded normally. Choroidal neovascularization was attenuated in Bcl-2EC mice, although retinal neovascularization accompanying oxygen-induced ischemic retinopathy was not. Thus, Bcl-2 expression in the endothelium plays a significant role during postnatal retinal vascularization, and pathological choroidal but not retinal neovascularization, suggesting vascular bed specific Bcl-2 function in the endothelium.

  7. Endothelium Expression of Bcl-2 Is Essential for Normal and Pathological Ocular Vascularization.

    Science.gov (United States)

    Zaitoun, Ismail S; Johnson, Ryan P; Jamali, Nasim; Almomani, Reem; Wang, Shoujian; Sheibani, Nader; Sorenson, Christine M

    2015-01-01

    Bcl-2 is an anti-apoptotic protein with important roles in vascular homeostasis and angiogenesis. Mice globally lacking Bcl-2 (Bcl-2 -/-) are small in stature and succumb to renal failure shortly after weaning as a result of renal hypoplasia/cystic dysplasia. We have shown that Bcl-2 -/- mice displayed attenuated retinal vascular development and neovascularization. In vitro studies indicated that in addition to modulating apoptosis, Bcl-2 expression also impacts endothelial and epithelial cell adhesion, migration and extracellular matrix production. However, studies delineating the cell autonomous role Bcl-2 expression plays in the endothelium during vascular development, pruning and remodeling, and neovascularization are lacking. Here we generated mice carrying a conditional Bcl-2 allele (Bcl-2Flox/Flox) and VE-cadherin-cre (Bcl-2EC mice). Bcl-2EC mice were of normal stature and lifespan and displayed some but not all of the retinal vascular defects previously observed in global Bcl-2 deficient mice. Bcl-2EC mice had decreased numbers of endothelial cells, decreased retinal arteries and premature primary branching of the retinal vasculature, but unlike the global knockout mice, spreading of the retinal superficial vascular layer proceeded normally. Choroidal neovascularization was attenuated in Bcl-2EC mice, although retinal neovascularization accompanying oxygen-induced ischemic retinopathy was not. Thus, Bcl-2 expression in the endothelium plays a significant role during postnatal retinal vascularization, and pathological choroidal but not retinal neovascularization, suggesting vascular bed specific Bcl-2 function in the endothelium. PMID:26444547

  8. Effects of apoptosis-related proteins caspase-3, Bax and Bcl-2 on cerebral ischemia rats

    OpenAIRE

    Liu, Guangyi; Tao WANG; WANG, TINGING; Song, Jinming; Zhou, Zhen

    2013-01-01

    Neuron apoptosis is known to mediate a change of ethology following cerebral ischemia-reperfusion injury in rats. Additionally, Bcl-2, Bax and caspase-3 proteins may exert a significant effect on neuron injury. The aim of this study was to investigate the role, mechanism of action and clinical significance of these proteins in neuron apoptosis and functional impairment following cerebral ischemia-reperfusion injury in rats. Sixty male healthy adult Wistar rats were randomly assigned into cont...

  9. Immunohistochemical Study Of Bcl-2 Protein And Estrogen Receptor-Alpha Expression In Benign Prostatic Hyperplasia And Prostatic Carcinoma

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    Ahmed H. Abel-Rahman- Ghada A. Abdel-Aziz*- Ali Emad S** Abdel

    2004-12-01

    independent prognostic indicator (P < 0.05. Thus, the immunohistochemical expression of ER and Bcl-2 protein in prostatic tissue may aid in better understanding the biology and genesis of both prostatic hyperplasia and carcinoma .

  10. Acetogenins from Annona muricata as potential inhibitors of antiapoptotic proteins: a molecular modeling study.

    Science.gov (United States)

    Antony, Priya; Vijayan, Ranjit

    2016-01-01

    Apoptosis is a highly regulated process crucial for maintaining cellular homeostasis and development. The B-cell lymphoma 2 (Bcl-2) family of proteins play a crucial role in regulating apoptosis. Overexpressed Bcl-2 proteins are associated with the development and progression of several human cancers. Annona muricata is a tropical plant that belongs to the Annonaceae family and is well known for its anticancer properties. In this study, molecular docking and simulations were performed to investigate the inhibitory potential of phytochemicals present in A. muricata against antiapoptotic proteins of the Bcl-2 family including Bcl-2, B-cell lymphoma extra-large (Bcl-Xl), and Mcl-1. Docking results revealed that the acetogenins, such as annomuricin A, annohexocin, muricatocin A, annomuricin-D-one, and muricatetrocin A/B, exhibited strong binding interactions with Bcl-Xl when compared to Bcl-2 and Mcl-1. Binding score and interactions of these acetogenins were notably better than those of currently available synthetic and natural inhibitors. Molecular dynamics simulations of the top-scoring lead molecules established that these molecules could bind strongly and consistently in the active site of Bcl-Xl. These results suggest that acetogenins could be explored as selective natural inhibitors of Bcl-Xl that could assist in promoting the intrinsic pathway of apoptosis.

  11. Acetogenins from Annona muricata as potential inhibitors of antiapoptotic proteins: a molecular modeling study

    Science.gov (United States)

    Antony, Priya; Vijayan, Ranjit

    2016-01-01

    Apoptosis is a highly regulated process crucial for maintaining cellular homeostasis and development. The B-cell lymphoma 2 (Bcl-2) family of proteins play a crucial role in regulating apoptosis. Overexpressed Bcl-2 proteins are associated with the development and progression of several human cancers. Annona muricata is a tropical plant that belongs to the Annonaceae family and is well known for its anticancer properties. In this study, molecular docking and simulations were performed to investigate the inhibitory potential of phytochemicals present in A. muricata against antiapoptotic proteins of the Bcl-2 family including Bcl-2, B-cell lymphoma extra-large (Bcl-Xl), and Mcl-1. Docking results revealed that the acetogenins, such as annomuricin A, annohexocin, muricatocin A, annomuricin-D-one, and muricatetrocin A/B, exhibited strong binding interactions with Bcl-Xl when compared to Bcl-2 and Mcl-1. Binding score and interactions of these acetogenins were notably better than those of currently available synthetic and natural inhibitors. Molecular dynamics simulations of the top-scoring lead molecules established that these molecules could bind strongly and consistently in the active site of Bcl-Xl. These results suggest that acetogenins could be explored as selective natural inhibitors of Bcl-Xl that could assist in promoting the intrinsic pathway of apoptosis. PMID:27110097

  12. Effect of low dose radiation on P53 and Bcl-2 protein expression in spermatogenic cells of mouse testis

    International Nuclear Information System (INIS)

    Objective: To investigate the effect of low dose radiation (LDR) with different dose of X-rays on P53 and Bcl-2 protein expression in spermatogenic cells of male Kunming mouse testis. Methods: The relationships between time-effect and dose-effect of P53 and Bcl-2 protein expression positive rate in spermatogenic cells of mouse testis after LDR with different dose of X-rays were studied with immunohistochemical technique (SABC). Results: P53 and Bcl-2 protein expressed in spermatogonia and spermatocytes in varying degrees, the positive rate of spermatogonia was obviously superior to that of spermatocytes. With the increase of irradiation dose, the expression of P53 protein showed a increasing tendency, however, the P53 protein expression of spermatozoa scarcely occurred after LDR. Bcl-2 protein was primarily expressed in spermatozoa. With the increase of irradiation dose, the positive rate of Bcl-2 protein expression showed a downregulated tendency. However, the Bcl-2 protein expression of spermatogonia and spermatocytes scarcely occurred after LDR. Conclusion: The expressions of P53 and Bcl-2 may have regular changes in mouse testis induced by LDR, which may provide a experimental evidence for the mechanism study of spermatogonic cell apoptosis induced selectively by ionizing radiation

  13. EXPRESSIONS OF P53, PROLIFERATING CELL NUCLEAR ANITIGEN, BCL-2 PROTEIN AND THEIR SIGNIFICANCE IN SALIVARY ADENOID CYSTIC CARCINOMA

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Objective To study the effects of P53, PCNA, Bcl-2 protein and their relationship in salivary adenoid cystic carcinoma(SACC). Methods These proteins were examined by immunohistochemistry. Results Overexpressions of P53 and PCNA were revealed in ACC samples, they were higher than those in (polymorphous adenomas) PA, but expression of Bcl-2 protein was not different between ACC and PA. In 3 subtypes of ACC, expressions of 3 proteins were different. Conclusion Mutations of P53, Bcl-2 may be involed in the occurrence of SACC, expression of PCNA and mutation of P53 may coexist in the development of the SACC.

  14. Effect of compound preparation Tongqiao Jiannao capsules on neural cell apoptosis and Bcl-2 and Bax protein levels in a rat model of brain ischemia/reperfusion injury

    Institute of Scientific and Technical Information of China (English)

    Rui Wang; Guanglai Li; Wei Wang; Huanying Li

    2008-01-01

    BACKGROUND: Pharmacological studies have demonstrated that compound preparation Tongqiao Jiannao capsules composed of Zexie, Baizhu, Honghua, Danshen, and Shexiang can supplement qi,activate blood circulation, relieve blood stasis, induce resuscitation for alleviating pain, relieve pain, anddilate blood vessels.OBJECTIVE: To observe the effects of Tongqiao Jiannao capsules on the levels of the anti-apoptotic protein Bcl-2 and the pro-apoptotic protein Bax, and verify the mechanism of action.DESIGN, TIME AND SETTING: Randomized, controlled animal experiment, performed in the Laboratory of Biochemistry and Molecular Biology, Shanxi Medical University between June 2001 and December 2002.MATERIALS: The right middle cerebral arteries of 24 healthy adult Sprague Dawley rats were occluded by the suture method. The primary Chinese herbal medicinal ingredients of Tongqiao Jiannao capsules are Zexie. Baizhu, Honghua, Danshen, and Shexiang, which were purchased from Shanxi Provincial Medicinal Material Company, China, and prepared into condensed granules in the Room for Chinese Herbal Medicine Preparation, Second Hospital, Shanxi Medical University. Bcl-2 and Bax immunohistochemical staining kits, a 3,3-diaminobenzidine(DAB) kit, and an in situ apoptosis detection kit were purchased from Wuhan Boster Bioengineering Co., Ltd., China.METHODS: Twenty-four rats were randomly and evenly divided into three groups: (1) sham-operated rats in which sutures were inserted and immediately pulled out; (2) Tongqiao Jiannao capsule-treated rats that were intragastrically administered 6.5 g/kg/d Tongqiao Jiannao capsule preparation for seven successive days prior to middle cerebral artery occlusion (MCAO); and (3) MCAO rats without any other treatments.MAIN OUTCOME MEASURES: The levels of neural cell apoptosis and Bcl-2 and Bax proteins at 24 hours post-surgery.RESULTS: In the MCAO group, the numbers of apoptotic cells and Bax-positive cells were significantly increased, while the numbers of

  15. The Expression of Apoptosis-Related Genes Bcl-2 and Bax Protein and Apoptosis Positivity in Cervical Carcinoma during Irradiation

    Institute of Scientific and Technical Information of China (English)

    ZHAODongli; SHIJingsen; LIMingzhong; SONGLiping; WANGShuwen

    2005-01-01

    Objective: To evaluate the apoptosis positivity, the expression of Bcl-2. bax proteins in 30 patients with squamous cell cervix carcinoma before and after radiotherapy. Methods: By using immunohistochemical and TDT-dUTP nick end labelling techniques. 30 cases of squamous cell cervical carcinoma were analyzed. Results: The apoptosis positivity before and after irradiation was 76.7%, and 100% respectively, with the difference being significant (P<0.05); The positive rates of Bcl-2 protein before and after irradiation were 73.3% and 46.7% respectively, with the difference being significant (P<0.05): The positive rates of bax protein before and after irradiation were 86% and 100 respectively, with the difference being significant (P<0.05). Conclusion: bax and Bcl-2 protein play an important role in apoptosis induced by fractionated radiation therapy. Apoptosis induced by irradiation is contributed to upregulation of bax protein or downregulation of Bcl-2 protein.

  16. The Action of Bcl-2 Apoptotic Family Proteins and Caspases in Mediating Follicle Atresia in Adult Mouse

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    Liliana Petculescu-Ciochină

    2011-05-01

    Full Text Available Among follicles present on the surface of the ovary only a small part reach ovulation, the majority entering atresia, which is an apoptotic process regulated hormonally in general. Apoptosis (from greek: apo = from, ptosis = falling - is a normal physiological process, genetically programmed cell death, which carries energy consumption by activating a program of internal suicide. This occurs at each stage of follicular development and is accompanied by a significant reduction in the number of follicles present at birth. Development stage-dependent mechanisms coordinate the evolution of follicles, leading to ovulation of a very small number of them. At follicular level apoptosis involves many morphological and biochemical processes that are based on pro-and anti-apoptotic members of Bcl-2 family of proteins (located on mitochondrial outer membrane and caspases. These changes aim internucleosomal DNA fragmentation, cell retraction followed by its wrinkling, cytoskeleton disruption, preservation of cytoplasmic organelles structure and function, loss of intercellular ties with the reduced expression of conexine 43 (key protein of communication junctions between granulose cells, progressive fragmentation of nucleus and cytoplasm, and finally the appearance of apoptotic bodies, and their inclusion by phagocytes, without the involvement of any inflammatory response.

  17. Hypoxia-induced modulation of apoptosis and BCL-2 family proteins in different cancer cell types.

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    Audrey Sermeus

    Full Text Available Hypoxia plays an important role in the resistance of tumour cells to chemotherapy. However, the exact mechanisms underlying this process are not well understood. Moreover, according to the cell lines, hypoxia differently influences cell death. The study of the effects of hypoxia on the apoptosis induced by 5 chemotherapeutic drugs in 7 cancer cell types showed that hypoxia generally inhibited the drug-induced apoptosis. In most cases, the effect of hypoxia was the same for all the drugs in one cell type. The expression profile of 93 genes involved in apoptosis as well as the protein level of BCL-2 family proteins were then investigated. In HepG2 cells that are strongly protected against cell death by hypoxia, hypoxia decreased the abundance of nearly all the pro-apoptotic BCL-2 family proteins while none of them are decreased in A549 cells that are not protected against cell death by hypoxia. In HepG2 cells, hypoxia decreased NOXA and BAD abundance and modified the electrophoretic mobility of BIM(EL. BIM and NOXA are important mediators of etoposide-induced cell death in HepG2 cells and the hypoxia-induced modification of these proteins abundance or post-translational modifications partly account for chemoresistance. Finally, the modulation of the abundance and/or of the post-translational modifications of most proteins of the BCL-2 family by hypoxia involves p53-dependent and -independent pathways and is cell type-dependent. A better understanding of these cell-to-cell variations is crucial in order to overcome hypoxia-induced resistance and to ameliorate cancer therapy.

  18. Expression of the bcl-2 oncogene protein is not specific for the 14;18 chromosomal translocation.

    OpenAIRE

    F. Pezzella(Istituto Nazionale di Fisica Nucleare, Sezione di Napoli, Complesso Universitario di Monte S. Angelo ed. 6, via Cintia, 80126 Napoli, Italy); Tse, A G; Cordell, J L; Pulford, K. A.; Gatter, K C; Mason, D Y

    1990-01-01

    It has been reported previously that the bcl-2 protooncogene protein is detectable in neoplastic cells from cases of human lymphoma in which the 14;18 chromosomal translocation is present, but not in lymphomas that lack this chromosomal rearrangement or in normal lymphoid tissue. In the present study we confirmed, by immunohistologic labeling with polyclonal and monoclonal antibodies, that bcl-2 protein is strongly expressed in many cases of follicular lymphoma and that these neoplastic folli...

  19. THE EXPERIMENTAL STUDY ON THE CELL APOPTOSIS AND EXPRESSION OF BCL-2 PROTEIN IN INTRACEREBRAL HEMORRHAGE IN MODEL OF RATS

    Institute of Scientific and Technical Information of China (English)

    Bao Gang; Guo Ning; Zhang Zhonglin; Chen Wei; Bao Dehu

    2006-01-01

    Otjective To study whether there is the apoptosis of neural cells and the expressionof Bcl-2 protein in intracerebral hemorrhage (ICH) in model of rats, for the further understanding the mechanism of the delayed damage of the neural cells around the hematoma after ICH. Methods Fifty SD rats were randomly divided into 5 groups, ten in each. With the Group A as the control, the rest 40 were used to set up intracerebral hemorrhage model. The brains were taken out at 12th, 24th, 48th and 72th hours, respectively. Apoptosis cells were detected with terminal deoxynucleotidyl transferase mediated dUTP nick end labeling (TUNEL), and the expression of Bcl-2 protein was detected with immunochemical stainging methed (SP). Results In the control group, no apoptosis cells and Bcl-2protein were detected. In rest groups, the apoptosis cells and Bcl-2 protein were expressed in different degree.Apoptosis rates verified and corresponded with the time after ICH, with the peak at 48th -72th hour after hemorrhage.The peak rate of apoptosis cells was (24. 50± 2.69)% and Bcl-2 protein expression was (20. 76 ± 1.97)% . There was significant difference between the experimental groups and control (P<0.05), and no linear relationship between the apoptosis rate and the expression of Bcl-2 protein. Conclusion Apoptosis may be an important factor in the secondary trauma of ICH. There is a time leg after hemorrhage. All this is instructive to clinical treatment in time. Bcl-2 protein keeps increasing in a certain time after hemorrhage, but not synchronize with the cell apoptosis. This indicates that bcl-2 has the effect to reduce the apoptosis of neural cells.

  20. Induction of apoptosis in HepG2 cells by solanine and Bcl-2 protein.

    Science.gov (United States)

    Ji, Y B; Gao, S Y; Ji, C F; Zou, X

    2008-01-17

    The nightshade (Solanum nigrum Linn.) has been widely used in Chinese traditional medicine as a remedy for the treatment of digestive system cancer. The anti-tumor activity of solanine, a steroid alkaloid isolated from the nightshade has been demonstrated. To observe the effect of anti-tumor and mechanism of solanine. The MTT assay was used to evaluate the IC(50) on the three digestive system tumor cell lines. The effect on the morphology was observed with a laser confocal microscopy; the rate of apoptosis and the cell cycle were measured using flow cytometry (FCM); the expression of Bcl-2 protein was measured by Western blot. The results show that the IC(50) for HepG(2), SGC-7901, and LS-174 were 14.47, >50, and >50 microg/ml, respectively; the morphology of cells in the negative control was normal; for the treated groups, typical signs for apoptosis were found. The rate of apoptosis in HepG(2) cells induced by solanine was found to be 6.0, 14.4, 17.3, 18.9, and 32.2%, respectively. Observation of the cell cycle showed that cells in the G(2)/M phases disappeared while the number of cells in the S phase increased significantly for treated groups. Western blot showed that solanine decreased the expression of Bcl-2 protein. Therefore, the target of solanine in inducing apoptosis in HepG(2) cells seems to be mediated by the inhibition in the expression of Bcl-2 protein.

  1. Functional Cooperation of the Proapoptotic Bcl2 Family Proteins Bmf and Bim In Vivo ▿

    OpenAIRE

    Hübner, Anette; Cavanagh-Kyros, Julie; Rincon, Mercedes; Richard A Flavell; Davis, Roger J

    2009-01-01

    Bcl2-modifying factor (Bmf) is a member of the BH3-only group of proapoptotic proteins. To test the role of Bmf in vivo, we constructed mice with a series of mutated Bmf alleles that disrupt Bmf expression, prevent Bmf phosphorylation by the c-Jun NH2-terminal kinase (JNK) on Ser74, or mimic Bmf phosphorylation on Ser74. We report that the loss of Bmf causes defects in uterovaginal development, including an imperforate vagina and hydrometrocolpos. We also show that the phosphorylation of Bmf ...

  2. Effect of Buspirone, Fluoxetine and 8-OH-DPAT on Striatal Expression of Bax, Caspase-3 and Bcl-2 Proteins in 6-Hydroxydopamine-Induced Hemi-Parkinsonian Rats

    OpenAIRE

    Hamdollah Sharifi; Alireza Nayebi; Safar Farajnia; Rasool Haddadi

    2015-01-01

    Purpose: The exact pathogenesis of sporadic parkinson’s disease (PD) is still unclear. Numerous evidences suggest involvement of apoptosis in the death of dopaminergic neurons. In this study we investigated the effect of sub-chronic administration of buspirone, fluoxetine and 8-hydroxy-2-[di-n-propylamino]tetralin (8-OH-DPAT) in 6-hydroxydopamine (6-OHDA)-lesioned rats and assayed striatal concentrations of apoptotic (Bax, Caspase3) and anti-apoptotic (Bcl-2) proteins. M...

  3. Bcl-2 regulates HIF-1alpha protein stabilization in hypoxic melanoma cells via the molecular chaperone HSP90.

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    Daniela Trisciuoglio

    Full Text Available BACKGROUND: Hypoxia-Inducible Factor 1 (HIF-1 is a transcription factor that is a critical mediator of the cellular response to hypoxia. Enhanced levels of HIF-1alpha, the oxygen-regulated subunit of HIF-1, is often associated with increased tumour angiogenesis, metastasis, therapeutic resistance and poor prognosis. It is in this context that we previously demonstrated that under hypoxia, bcl-2 protein promotes HIF-1/Vascular Endothelial Growth Factor (VEGF-mediated tumour angiogenesis. METHODOLOGY/PRINCIPAL FINDINGS: By using human melanoma cell lines and their stable or transient derivative bcl-2 overexpressing cells, the current study identified HIF-1alpha protein stabilization as a key regulator for the induction of HIF-1 by bcl-2 under hypoxia. We also demonstrated that bcl-2-induced accumulation of HIF-1alpha protein during hypoxia was not due to an increased gene transcription or protein synthesis. In fact, it was related to a modulation of HIF-1alpha protein expression at a post-translational level, indeed its degradation rate was faster in the control lines than in bcl-2 transfectants. The bcl-2-induced HIF-1alpha stabilization in response to low oxygen tension conditions was achieved through the impairment of ubiquitin-dependent HIF-1alpha degradation involving the molecular chaperone HSP90, but it was not dependent on the prolyl hydroxylation of HIF-1alpha protein. We also showed that bcl-2, HIF-1alpha and HSP90 proteins form a tri-complex that may contribute to enhancing the stability of the HIF-1alpha protein in bcl-2 overexpressing clones under hypoxic conditions. Finally, by using genetic and pharmacological approaches we proved that HSP90 is involved in bcl-2-dependent stabilization of HIF-1alpha protein during hypoxia, and in particular the isoform HSP90beta is the main player in this phenomenon. CONCLUSIONS/SIGNIFICANCE: We identified the stabilization of HIF-1alpha protein as a mechanism through which bcl-2 induces the

  4. Bcl-2 Regulates HIF-1α Protein Stabilization in Hypoxic Melanoma Cells via the Molecular Chaperone HSP90

    Science.gov (United States)

    Trisciuoglio, Daniela; Gabellini, Chiara; Desideri, Marianna; Ziparo, Elio; Zupi, Gabriella; Del Bufalo, Donatella

    2010-01-01

    Background Hypoxia-Inducible Factor 1 (HIF-1) is a transcription factor that is a critical mediator of the cellular response to hypoxia. Enhanced levels of HIF-1α, the oxygen-regulated subunit of HIF-1, is often associated with increased tumour angiogenesis, metastasis, therapeutic resistance and poor prognosis. It is in this context that we previously demonstrated that under hypoxia, bcl-2 protein promotes HIF-1/Vascular Endothelial Growth Factor (VEGF)-mediated tumour angiogenesis. Methodology/Principal Findings By using human melanoma cell lines and their stable or transient derivative bcl-2 overexpressing cells, the current study identified HIF-1α protein stabilization as a key regulator for the induction of HIF-1 by bcl-2 under hypoxia. We also demonstrated that bcl-2-induced accumulation of HIF-1α protein during hypoxia was not due to an increased gene transcription or protein synthesis. In fact, it was related to a modulation of HIF-1α protein expression at a post-translational level, indeed its degradation rate was faster in the control lines than in bcl-2 transfectants. The bcl-2-induced HIF-1α stabilization in response to low oxygen tension conditions was achieved through the impairment of ubiquitin-dependent HIF-1α degradation involving the molecular chaperone HSP90, but it was not dependent on the prolyl hydroxylation of HIF-1α protein. We also showed that bcl-2, HIF-1α and HSP90 proteins form a tri-complex that may contribute to enhancing the stability of the HIF-1α protein in bcl-2 overexpressing clones under hypoxic conditions. Finally, by using genetic and pharmacological approaches we proved that HSP90 is involved in bcl-2-dependent stabilization of HIF-1α protein during hypoxia, and in particular the isoform HSP90β is the main player in this phenomenon. Conclusions/Significance We identified the stabilization of HIF-1α protein as a mechanism through which bcl-2 induces the activation of HIF-1 in hypoxic tumour cells involving the

  5. BAG1: the guardian of anti-apoptotic proteins in acute myeloid leukemia.

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    Sanja Aveic

    Full Text Available BCL2 associated Athano-Gene 1 (BAG1 is a multifunctional protein that has been described to be involved in different cell processes linked to cell survival. It has been reported as deregulated in diverse cancer types. Here, BAG1 protein was found highly expressed in children with acute myeloid leukemia at diagnosis, and in a cohort of leukemic cell lines. A silencing approach was used for determining BAG1's role in AML, finding that its down-regulation decreased expression of BCL2, BCL-XL, MCL1, and phospho-ERK1/2, all proteins able to sustain leukemia, without affecting the pro-apoptotic protein BAX. BAG1 down-regulation was also found to increase expression of BAG3, whose similar activity was able to compensate the loss of function of BAG1. BAG1/BAG3 co-silencing caused an enhanced cell predisposition to death in cell lines and also in primary AML cultures, affecting the same proteins. Cell death was CASPASE-3 dependent, was accompanied by PARP cleavage and documented by an increased release of pro-apoptotic molecules Smac/DIABLO and Cytochrome c. BAG1 was found to directly maintain BCL2 and to protect MCL1 from proteasomal degradation by controlling USP9X expression, which appeared to be its novel target. Finally, BAG1 was found able to affect leukemia cell fate by influencing the expression of anti-apoptotic proteins crucial for AML maintenance.

  6. Associations of MMP-2, BAX, and Bcl-2 mRNA and Protein Expressions with Development of Atrial Fibrillation.

    Science.gov (United States)

    Diao, Shu-Ling; Xu, Hui-Pu; Zhang, Bei; Ma, Bao-Xin; Liu, Xian-Liang

    2016-01-01

    BACKGROUND To examine changes of mRNA and protein expressions of MMP-2, Bcl-2, and BAX in atrial fibrillation (AF) patients, and investigate the correlations among these 3 biomarkers. MATERIAL AND METHODS Rheumatic heart disease patients (n=158) undergoing cardiac surgical procedures for mitral valve repair or replacement were included as the AF group (n=123), containing paroxysmal AF (n=42), persistent AF (n=36), and permanent AF (n=45). Rheumatic heart disease patients with sinus rhythm (SR) (n=35) were enrolled as the SR group (control group). Immunohistochemistry, Western blot, and real-time polymerase chain reaction (PCR) were applied to detect the protein and mRNA expression levels of MMP-2, Bcl-2, and BAX. Apoptosis was observed with light and electron microscopes and detected by TdT-mediated dUTP nick-end labeling (TUNEL). RESULTS Compared with the SR group, the left atrial diameters (LADs), protein and mRNA expression levels of MMP-2 and BAX, apoptotic index (AI), and Bcl-2/BAX ratio were evidently increased in the 3 AF groups, but protein and mRNA expression levels of Bcl-2 decreased in the AF groups (all P<0.05). Correlation analysis found that MMP-2 protein expression levels was positively correlated with BAX expression, but negatively correlated with Bcl-2 expression levels. CONCLUSIONS Our study results suggest that elevated MMP-2 expression and disturbance balance of Bcl-2/BAX expressions may be associated with the development and maintenance of AF. MMP-2 may be involved in the development of AF through promoting BAX expressions and inhibiting Bcl-2. PMID:27141955

  7. Bcl-2 protein expression in lung cancer and close correlation with neuroendocrine differentiation.

    OpenAIRE

    Jiang, S. X.; Kameya, T.; Sato, Y.; Yanase, N.; Yoshimura, H.; Kodama, T

    1996-01-01

    For determination of the cellular distribution of bcl-2 expression in lung cancer and clarification of its correlation with cell neuroendocrine differentiation, Bcl-2 immunostaining was carried out on a large series of formalin-fixed, paraffin-embedded lung cancer samples, and four general neuroendocrine marker and seven peptide hormone stainings were carried out on all Bcl-2-positive squamous cell carcinomas and adenocarcinomas of the lung as well as on 8 pulmonary neuroendocrine carcinomas ...

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

    Directory of Open Access Journals (Sweden)

    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.

  9. BEX1 promotes imatinib-induced apoptosis by binding to and antagonizing BCL-2.

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    Qian Xiao

    Full Text Available An enhanced anti-apoptotic capacity of tumor cells plays an important role in the process of breakpoint cluster region/Abelson tyrosine kinase gene (BCR/ABL-independent imatinib resistance. We have previously demonstrated that brain expressed X-linked 1 (BEX1 was silenced in secondary imatinib-resistant K562 cells and that re-expression of BEX1 can restore imatinib sensitivity resulting in the induction of apoptosis. However, the mechanism by which BEX1 executes its pro-apoptotic function remains unknown. We identified B-cell lymphoma 2 (BCL-2 as a BEX1-interacting protein using a yeast two-hybrid screen. The interaction between BEX1 and BCL-2 was subsequently confirmed by co-immunoprecipitation assays. Like BCL-2, BEX1 was localized to the mitochondria. The region between 33K and 64Q on BEX1 is important for its localization to the mitochondria and its ability to interact with BCL-2. Additionally, we found that this region is essential for BEX1-regulated imatinib-induced apoptosis. Furthermore, we demonstrated that the interaction between BCL-2 and BEX1 promotes imatinib-induced apoptosis by suppressing the formation of anti-apoptotic BCL-2/BCL-2-associated X protein (BAX heterodimers. Our results revealed an interaction between BEX1 and BCL-2 and a novel mechanism of imatinib resistance mediated by the BEX1/BCL-2 pathway.

  10. Expressions of bcl-2 and P53 protein in Bowen's disease%Bowen病bcl-2及P53蛋白的表达

    Institute of Scientific and Technical Information of China (English)

    张士发; 王良明; 赵丽萍; 许静; 顾绍裘

    2004-01-01

    目的:探讨bcl-2及P53蛋白在Bowen病及Bowen样鳞癌中的表达及其意义.方法:应用免疫组织化学技术对11例Bowen病及3例Bowen样鳞癌bcl-2和/或P53蛋白的表达进行了检测.结果:11例Bowen病中bcl-2蛋白阳性2例(18%),P53蛋白阳性3例(27%);3例Bowen样鳞癌均见bcl-2蛋白表达.Bowen病中bcl-2与P53蛋白表达显著正相关(r=0.769,P<0.05).结论:Bowen病中bcl-2蛋白表达与P53基因突变有关,并参与了Bowen病的进展及向Bowen样鳞癌的演变.

  11. Bcl-2 Inhibitors: Targeting Mitochondrial Apoptotic Pathways in Cancer Therapy

    OpenAIRE

    Kang, Min H.; Reynolds, C. Patrick

    2009-01-01

    Defects in apoptotic pathways can promote cancer cell survival and also confer resistance to antineoplastic drugs. One pathway being targeted for antineoplastic therapy is the anti-apoptotic B-cell lymphoma-2 (Bcl-2) family of proteins (Bcl-2, Bcl-XL, Bcl-w, Mcl-1, Bfl1/A-1, and Bcl-B) that bind to and inactivate BH3-domain pro-apoptotic proteins. Signals transmitted by cellular damage (including antineoplastic drugs) or cytokine deprivation can initiate apoptosis via the intrinsic apoptotic ...

  12. Cytotoxicity of carteolol to human corneal epithelial cells by inducing apoptosis via triggering the Bcl-2 family protein-mediated mitochondrial pro-apoptotic pathway.

    Science.gov (United States)

    Shan, Ming; Fan, Ting-Jun

    2016-09-01

    Carteolol is a frequently used nonselective β-adrenoceptor antagonist for glaucoma and ocular hypertension treatment, and its repeated/prolonged usage might be cytotoxic to the cornea, especially the outmost human corneal epithelium (HCEP). The aim of the present study was to characterize the cytotoxicity of carteolol to HCEP and its underlying cellular and molecular mechanisms using an in vitro model of HCEP cells. After HCEP cells were treated with carteolol at concentrations varying from 2% to 0.015625%, the cytotoxicity, apoptosis-inducing effect and pro-apoptotic pathway was investigated, respectively. Our results showed that carteolol at concentrations above 0.03125% induced time- and dose-dependent growth retardation, cytopathic morphological changes and viability decline of HCEP cells. Moreover, carteolol induced G1 phase arrest, plasma membrane permeability elevation, phosphatidylserine externalization, DNA fragmentation, and apoptotic body formation of HCEP cells. Furthermore, carteolol also induced activation of caspase-9 and -3, disruption of mitochondrial transmembrane potential, up-regulation the cytoplasmic amount of cytochrome c and apoptosis-inducing factor, and up-regulation of pro-apoptotic Bax and Bad, down-regulation of anti-apoptotic Bcl-2 and Bcl-xL. In conclusion, carteolol above 1/64 of its clinical therapeutic dosage has a time- and dose-dependent cytotoxicity to HCEP cells, which is achieved by inducing apoptosis via triggering Bcl-2 family protein-mediated mitochondrial pro-apoptotic pathway. PMID:27216471

  13. Relationship between expression of Bax and Bcl-2 proteins and apoptosis in radiation compound wound healing of rats

    Institute of Scientific and Technical Information of China (English)

    崔玉芳; 夏国伟; 付小兵; 杨红; 彭瑞云; 张莹; 谷庆阳; 高亚兵; 崔雪梅; 胡文华

    2003-01-01

    Objective: To study the relationship between the expression of Bax, Bcl-2 proteins, and apoptosis in radiation compound wound healing of rats.Methods: Apoptosis, Bax and Bcl-2 proteins were estimated by in situ terminal labeling (TUNEL) and immunohistochemical methods. Results: (1) Changes of the apoptosis in wound healing showed three typical characteristics: early occurrence, high frequency and delayed disappearance after radiation to rats when compared with those of simple wound group, which might be an important reason for radiation-induced delayed wound healing. (2) The expression of Bax protein increased evidently with the increment of apoptosis and showed a good corresponding relationship with the apoptotic frequency in the process of wound healing. While the expression of Bcl-2 protein decreased obviously as the apoptosis reached a maximum and showed increasing tendency up to normal level when the apoptosis decreased distinctively. Conclusions: Bax and Bcl-2 proteins play an important role in the apoptotic regulation of radiation compound wound healing in rats.

  14. 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.

  15. Sheeppox Virus SPPV14 Encodes a Bcl-2-Like Cell Death Inhibitor That Counters a Distinct Set of Mammalian Proapoptotic Proteins

    OpenAIRE

    Okamoto, Toru; Campbell, Stephanie; Mehta, Ninad; Thibault, John; Colman, Peter M.; Barry, Michele; Huang, David C. S.; Kvansakul, Marc

    2012-01-01

    Many viruses express inhibitors of programmed cell death (apoptosis), thereby countering host defenses that would otherwise rapidly clear infected cells. To counter this, viruses such as adenoviruses and herpesviruses express recognizable homologs of the mammalian prosurvival protein Bcl-2. In contrast, the majority of poxviruses lack viral Bcl-2 (vBcl-2) homologs that are readily identified by sequence similarities. One such virus, myxoma virus, which is the causative agent of myxomatosis, e...

  16. Estimation of BCL-2 protein in carcinoma of the breast and its clinical correlation in locally advanced breast cancer

    Directory of Open Access Journals (Sweden)

    Aggarwal Himanshu

    2007-01-01

    Full Text Available The change in expression of apoptotic markers (Bcl-2 and Bax proteins brought about by various chemotherapeutic regimens is being used for its predictive value for assessing response to neoadjuvant chemotherapy (NACT in locally advanced breast carcinoma (LABC. Aims: (1 Estimation of Bcl 2 expression in LABC, (2 Any change in Bcl 2 expression following chemotherapy in LABC, (3 Any relation of Bcl 2 estimation to changes in size of tumor, nodal status, age, and menopausal status. Settings and Design: This was a prospective study of 120 cases of LABC. Materials and Methods: All cases were subjected to biopsy and the tissue was evaluated immunohistochemically for apoptotic marker Bcl-2 family protein. Three cycles of NACT were given at three-weekly intervals. Modified radical mastectomy was performed and the specimens were re-evaluated for any change in the Bcl-2 family protein. The clinical response and immunohistochemical response were correlated and compared. Statistical Analysis: Coefficient of correlation was calculated by Pearson correlation coefficient (P-value. Results: Clinical response, as measured by reduction in the tumor size, was observed in 81 (67.5% patients while immunohistochemical response was observed in 67 (55.8% patients. Correlation between immunohistochemical and clinical response was found to be statistically significant (P = 0.02. Nodal response was seen in 72 (60% patients. There were no patients in the N o group; 22 (53.7% of the N 1 patients were down-staged to N o , while 19 (46.3% remained N 1 . In patients with N 2 disease, 11 (13.9% were down-staged to N o status, 39 (49.4% were down-staged to N 1 status, and 29 (36.7% did not show any response. Immunohistochemical response was observed in 67 (55.8% patients. Correlation between immunohistochemical and nodal responses was also found to be statistically significant (P = 0.03. Conclusions: This significant positive correlation between clinical and immunohistochemical

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

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    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

  18. Inhibition of Bcl-2 or IAP proteins does not provoke mutations in surviving cells

    International Nuclear Information System (INIS)

    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

  19. 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

  20. MicroRNA-125b Induces Cancer Cell Apoptosis Through Suppression of Bcl-2 Expression

    Institute of Scientific and Technical Information of China (English)

    Aihua Zhao; Quan Zeng; Xiaoyan Xie; unnian Zhou; Wen Yue; Yali Li; Xuetao Pei

    2012-01-01

    MicroRNAs (miRNAs) are small,noncoding RNAs which can often act as an oncogene or a tumor suppressor.Several miRNAs are associated with the development of hepatocellular carcinoma (HCC).We demonstrated that miR-125b significantly suppresses HCC cell proliferation and promotes apoptosis by inhibiting the gene expression of the anti-apoptotic protein,Bcl-2.Bioinformatic analysis indicated that the 3'UTR of Bcl-2 has binding sites for miR-125b.Luciferase reporter assay confirmed the ability of miR-125b to dramatically suppress Bcl-2 transcription,suggesting that Bcl-2 is a target gene for miR-125b.We concluded that miR-125b acts as a tumor suppressor in hepatic tumor development by targeting Bcl-2 and inducing cancer cell apoptosis.

  1. Alpha-helical destabilization of the Bcl-2-BH4-domain peptide abolishes its ability to inhibit the IP3 receptor.

    Directory of Open Access Journals (Sweden)

    Giovanni Monaco

    Full Text Available The anti-apoptotic Bcl-2 protein is the founding member and namesake of the Bcl-2-protein family. It has recently been demonstrated that Bcl-2, apart from its anti-apoptotic role at mitochondrial membranes, can also directly interact with the inositol 1,4,5-trisphosphate receptor (IP3R, the primary Ca(2+-release channel in the endoplasmic reticulum (ER. Bcl-2 can thereby reduce pro-apoptotic IP3R-mediated Ca(2+ release from the ER. Moreover, the Bcl-2 homology domain 4 (Bcl-2-BH4 has been identified as essential and sufficient for this IP3R-mediated anti-apoptotic activity. In the present study, we investigated whether the reported inhibitory effect of a Bcl-2-BH4 peptide on the IP 3R1 was related to the distinctive α-helical conformation of the BH4 domain peptide. We therefore designed a peptide with two glycine "hinges" replacing residues I14 and V15, of the wild-type Bcl-2-BH4 domain (Bcl-2-BH4-IV/GG. By comparing the structural and functional properties of the Bcl-2-BH4-IV/GG peptide with its native counterpart, we found that the variant contained reduced α-helicity, neither bound nor inhibited the IP 3R1 channel, and in turn lost its anti-apoptotic effect. Similar results were obtained with other substitutions in Bcl-2-BH4 that destabilized the α-helix with concomitant loss of IP3R inhibition. These results provide new insights for the further development of Bcl-2-BH4-derived peptides as specific inhibitors of the IP3R with significant pharmacological implications.

  2. BCL-2 family protein, BAD is down-regulated in breast cancer and inhibits cell invasion

    Energy Technology Data Exchange (ETDEWEB)

    Cekanova, Maria, E-mail: mcekanov@utk.edu [Department of Small Animal Clinical Sciences, College of Veterinary Medicine, The University of Tennessee, Knoxville, TN (United States); Fernando, Romaine I. [Department of Obstetrics and Gynecology, Graduate School of Medicine, Medical Center, The University of Tennessee, Knoxville, TN (United States); Siriwardhana, Nalin [Department of Animal Science, The University of Tennessee, Knoxville, TN (United States); Sukhthankar, Mugdha [Department of Biomedical and Diagnostics Sciences, College of Veterinary Medicine, The University of Tennessee, Knoxville, TN (United States); Parra, Columba de la [Department of Biochemistry, School of Medicine, University of Puerto Rico, Medical Sciences Campus, San Juan, PR (United States); Woraratphoka, Jirayus [Department of Obstetrics and Gynecology, Graduate School of Medicine, Medical Center, The University of Tennessee, Knoxville, TN (United States); Malone, Christine [Laboratory of Molecular Carcinogenesis, National Institute of Environmental Health Sciences, Research Triangle Park, NC (United States); Ström, Anders [Center for Nuclear Receptors and Cell Signaling, Department of Biology and Biochemistry, University of Houston, Houston, TX (United States); Baek, Seung J. [Department of Biomedical and Diagnostics Sciences, College of Veterinary Medicine, The University of Tennessee, Knoxville, TN (United States); Wade, Paul A. [Laboratory of Molecular Carcinogenesis, National Institute of Environmental Health Sciences, Research Triangle Park, NC (United States); Saxton, Arnold M. [Department of Animal Science, The University of Tennessee, Knoxville, TN (United States); Donnell, Robert M. [Department of Biomedical and Diagnostics Sciences, College of Veterinary Medicine, The University of Tennessee, Knoxville, TN (United States); Pestell, Richard G. [Department of Cancer Biology, Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA (United States); and others

    2015-02-01

    We have previously demonstrated that the anti-apoptotic protein BAD is expressed in normal human breast tissue and shown that BAD inhibits expression of cyclin D1 to delay cell-cycle progression in breast cancer cells. Herein, expression of proteins in breast tissues was studied by immunohistochemistry and results were analyzed statistically to obtain semi-quantitative data. Biochemical and functional changes in BAD-overexpressing MCF7 breast cancer cells were evaluated using PCR, reporter assays, western blotting, ELISA and extracellular matrix invasion assays. Compared to normal tissues, Grade II breast cancers expressed low total/phosphorylated forms of BAD in both cytoplasmic and nuclear compartments. BAD overexpression decreased the expression of β-catenin, Sp1, and phosphorylation of STATs. BAD inhibited Ras/MEK/ERK and JNK signaling pathways, without affecting the p38 signaling pathway. Expression of the metastasis-related proteins, MMP10, VEGF, SNAIL, CXCR4, E-cadherin and TlMP2 was regulated by BAD with concomitant inhibition of extracellular matrix invasion. Inhibition of BAD by siRNA increased invasion and Akt/p-Akt levels. Clinical data and the results herein suggest that in addition to the effect on apoptosis, BAD conveys anti-metastatic effects and is a valuable prognostic marker in breast cancer. - Highlights: • BAD and p-BAD expressions are decreased in breast cancer compared with normal breast tissue. • BAD impedes breast cancer invasion and migration. • BAD inhibits the EMT and transcription factors that promote cancer cell migration. • Invasion and migration functions of BAD are distinct from the BAD's role in apoptosis.

  3. BCL-2 family protein, BAD is down-regulated in breast cancer and inhibits cell invasion

    International Nuclear Information System (INIS)

    We have previously demonstrated that the anti-apoptotic protein BAD is expressed in normal human breast tissue and shown that BAD inhibits expression of cyclin D1 to delay cell-cycle progression in breast cancer cells. Herein, expression of proteins in breast tissues was studied by immunohistochemistry and results were analyzed statistically to obtain semi-quantitative data. Biochemical and functional changes in BAD-overexpressing MCF7 breast cancer cells were evaluated using PCR, reporter assays, western blotting, ELISA and extracellular matrix invasion assays. Compared to normal tissues, Grade II breast cancers expressed low total/phosphorylated forms of BAD in both cytoplasmic and nuclear compartments. BAD overexpression decreased the expression of β-catenin, Sp1, and phosphorylation of STATs. BAD inhibited Ras/MEK/ERK and JNK signaling pathways, without affecting the p38 signaling pathway. Expression of the metastasis-related proteins, MMP10, VEGF, SNAIL, CXCR4, E-cadherin and TlMP2 was regulated by BAD with concomitant inhibition of extracellular matrix invasion. Inhibition of BAD by siRNA increased invasion and Akt/p-Akt levels. Clinical data and the results herein suggest that in addition to the effect on apoptosis, BAD conveys anti-metastatic effects and is a valuable prognostic marker in breast cancer. - Highlights: • BAD and p-BAD expressions are decreased in breast cancer compared with normal breast tissue. • BAD impedes breast cancer invasion and migration. • BAD inhibits the EMT and transcription factors that promote cancer cell migration. • Invasion and migration functions of BAD are distinct from the BAD's role in apoptosis

  4. Melatonin restores normal Bax and Bcl-2 protein expression in the subgranular zone of the dentate gyrus in pinealectomized rats

    Institute of Scientific and Technical Information of China (English)

    Shengchang Zhang; Shuang Zhao; Lu Bai; Mingming Guan; Jielin Mo; Ling Lan

    2011-01-01

    In this study, we sought to elucidate the effects of melatonin on learning and memory as well as apoptosis and expression of the Bax or Bcl-2 proteins in the subgranular zone of the dentate gyrus in pinealectomized rats. Using the Morris water maze and the olfactory memory tests, we found that the average escape latency in pinealectomized rats was clearly increased compared with sham-operated rats. Moreover, the average escape latency in the melatonin-treated and pinealectomized rats was longer than that in the sham-operated rats and shorter than that in the pinealectomized and untreated rats. Immunohistochemistry and terminal-deoxynucleoitidyl transferase mediated nick end labeling (TUNEL) showed that there were fewer Bax immunoreactive cells and TUNEL-positive (apoptotic) cells but more Bcl-2 immunoreactive cells in the melatonin-treated rats compared with the pinealectomized rats. The sham-operated rats showed numbers of these cells similar to the melatonin-treated rats. These experimental findings demonstrate that melatonin treatment may reduce abnormal apoptosis by promoting gene expression of Bax and suppressing gene expression of Bcl-2 in the subgranular zone of the dentate gyrus in pinealectomized rats. These effects appear to result in the inhibition of cellular apoptosis and the improvement of spatial learning and memory in pinealectomized rats.

  5. Dioscorealide B from the traditional Thai medicine Hua-Khao-Yen induces apoptosis in MCF-7 human breast cancer cells via modulation of Bax, Bak and Bcl-2 protein expression.

    Science.gov (United States)

    Saekoo, Jiraporn; Graidist, Potchanapond; Leeanansaksiri, Wilairat; Dechsukum, Chavaboon; Itharat, Arunporn

    2010-12-01

    Dioscorealide B is a pharmacologically active compound from the rhizome of the Thai medicinal plant Dioscorea membranacea. Here, we demonstrated that in vitro treatment of dioscorealide B resulted in a cytotoxic effect on MCF-7 human breast cancer cells (IC50 = 2.82 microM). To determine whether this compound induces apoptosis in MCF-7, the Annexin V assay was performed. The data showed that the number of apoptotic cells were increased 7-12 folds over that of the control cells after treatment with various concentrations of dioscorealide B (3, 6 and 12 microM) for 24 hours. Dioscorealide B-induced apoptosis was associated with modulation of the multidomain Bcl-2 family members Bax, Bak and Bcl-2. After treatment with 3 microM dioscorealide B, acceleration of the level of proapoptotic proteins Bax and Bak were observed at 6 hours and 12 hours, respectively, while the decrease in the expression of antiapoptotic protein Bcl-2 was observed 3 hours after the treatment. These effects of dioscorealide B might result in the activation of caspase-8, -9 and -7, which lead to apoptosis in MCF-7 cells. Taken together, the results of this study provide evidence that dioscorealide B possesses an antitumor property against human breast cancer cells and thus provide the molecular basis for the further development of dioscorealide B as a novel chemotherapeutic agent for breast cancer treatment. PMID:21299121

  6. 听神经瘤BCL-2蛋白及bcl-2/JH融合基因的研究☆%Detection of BCL-2 protooncogene protein expression and the related bcl-2(mbr)/JH fusion gene from archival paraffin-embedded tissue from acoustic neuromas.

    Institute of Scientific and Technical Information of China (English)

    刘绍明; 李龄; 刘鹏翀

    2001-01-01

    目的评价石蜡包埋听神经瘤组织中BGL-2蛋白表达及相关的bcl-2(mbr)/JH融合基因改变,以探讨bcl-2癌基因在听神经瘤发病中的可能意义.方法免疫组化检测石蜡包埋组织中BCL-2蛋白的表达;提取石蜡包埋组织的DNA,PCR检测bcl-2(mbr)/JH融合基因.结果本组40例听神经瘤,BCL-2蛋白表达阳性27例(67.5%),bcl-2(mbr)/JH融合基因检出阳性19例(47.5%).结论听神经瘤中存在BCL-2蛋白的高表达及t(14;18)染色体易位,提示雪旺氏细胞凋亡抑制可能是听神经瘤发病的分子病理基础之一.

  7. Carboxypeptidase E protects hippocampal neurons during stress in male mice by up-regulating prosurvival BCL2 protein expression.

    Science.gov (United States)

    Murthy, S R K; Thouennon, E; Li, W-S; Cheng, Y; Bhupatkar, J; Cawley, N X; Lane, M; Merchenthaler, I; Loh, Y P

    2013-09-01

    Prolonged chronic stress causing elevated plasma glucocorticoids leads to neurodegeneration. Adaptation to stress (allostasis) through neuroprotective mechanisms can delay this process. Studies on hippocampal neurons have identified carboxypeptidase E (CPE) as a novel neuroprotective protein that acts extracellularly, independent of its enzymatic activity, although the mechanism of action is unclear. Here, we aim to determine if CPE plays a neuroprotective role in allostasis in mouse hippocampus during chronic restraint stress (CRS), and the molecular mechanisms involved. Quantitative RT-PCR/in situ hybridization and Western blots were used to assay for mRNA and protein. After mild CRS (1 h/d for 7 d), CPE protein and mRNA were significantly elevated in the hippocampal CA3 region, compared to naïve littermates. In addition, luciferase reporter assays identified a functional glucocorticoid regulatory element within the cpe promoter that mediated the up-regulation of CPE expression in primary hippocampal neurons following dexamethasone treatment, suggesting that circulating plasma glucocorticoids could evoke a similar effect on CPE in the hippocampus in vivo. Overexpression of CPE in hippocampal neurons, or CRS in mice, resulted in elevated prosurvival BCL2 protein/mRNA and p-AKT levels in the hippocampus; however, CPE(-/-) mice showed a decrease. Thus, during mild CRS, CPE expression is up-regulated, possibly contributed by glucocorticoids, to mediate neuroprotection of the hippocampus by enhancing BCL2 expression through AKT signaling, and thereby maintaining allostasis.

  8. Synergistic antitumoral activity and induction of apoptosis by novel pan Bcl-2 proteins inhibitor apogossypolone with adriamycin in human hepatocellular carcinoma

    Institute of Scientific and Technical Information of China (English)

    Jin-xia MI; Guang-feng WANG; Heng-bang WANG; Xiao-qing SUN; Xin-yan NI; Xiong-wen ZHANG; Jia-ming TANG; Da-jun YANG

    2008-01-01

    Aim: To investigate the in vitro and in vivo activities and related mechanism of apogossypoione (ApoG2) alone or in combination with adriamycin (ADM) against human hepatocellular carcinoma (HCC). Methods: The IC50 of ApoG2 in vitro was tested by WST assay, and the synergistic effect was analyzed using the CalcuSyn method. Cell apoptosis was determined using 4',6-diamidino-2-phenylindole staining and flow cytometric analysis. Western blotting was used to determine the expression of apoptosis-related proteins. In vivo activity was evaluated in the xenograft model in nude mice, and apoptosis in tumor tissues was determined by terminal deoxynucleotidyl transferase-mediated digoxigenin-dUTP nick-end labeling (TUNEL) assay. Results: The IC50 of ApoG2 in HCC cells was 17.28-30.63 μmol/L. When ApoG2 was combined with ADM, in-creased cytotoxicity and apoptosis were observed in SMMC-7721 cells compared to treatment with ApoG2 alone. The Western blotting results indicated that the ApoG2 induced apoptosis in SMMC-7721 cells by downregulating anti-apoptotic proteins Bcl-2, Mcl-1, and Bcl-XL, up-regulating pro-apoptotic protein Noxa, and promoting the activities of caspases-9 and -3. The tumor growth of xenograft SMMC-7721 was inhibited in nude mice when ApoG2 was administered orally without causing damage to the normal tissues. The in vivo study also indicated an increasing anti-tumoral effect when ApoG2 at 100 or 200 mg/kg dosages were used together with ADM at 5.5 mg/kg, with relative tumor proliferation rate (T/C) values of 0.456 and 0.323, respectively. Apoptosis induced in vivo by ApoG2 alone or combined with ADM was confirmed by TUNEL assay in tumor tissues. Conclusion: ApoG2 is a potential non-toxic target agent that induces apoptosis by upregulating Noxa, while inhibiting anti-apoptotic proteins and pro-moting the effect of chemotherapy agent ADM in HCC.

  9. Detection of apoptotic cells and immunohistochemical study of bcl-2 and p53 gene protein in primary gastric mucosa-associated lymphoid tissue (MALT) lymphoma

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Objective: To identify the apoptotic cells in gastric MALT lymphoma and its relationship between bcl-2 and p53 gene expression. Methods: TdT-mediated dUTP biotin Nick End labeling (TUNEL) and immuno-histochemistry ABC method were used to display apoptotic cells and the gene protein expression of bcl-2 and p53 independently. Results: Apoptotic indices (AI) in high-grade MALT lymphomas were significantly higher than in mixed-grade group and low-grade group (P<0.05). Bcl-2 was expressed in 83% of low-grade tumors, 61.6% of the median-grade tumors and 43.7% of high-grade tumors. An inverse correlation was observed between the expression of bcl-2 and apoptotic indices. Only 27 cases were p53 positive. The frequency of p53 positivity was significantly increased as the histologic grade advanced (P<0.05). There was also an inverse correlation between the expression of bcl-2 and p53. Conclusion: Apoptosis may be important in tumors development and transmission. P53 and bcl-2 were important regulatory genes of apoptosis and may be associated with transformation from low-grade to high-grade lymphomas.

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

    International Nuclear Information System (INIS)

    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 (iAsIII) 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: iAsIII induced growth inhibition, G2-M arrest and apoptotic cell death in MSCs, the apoptosis induced by iAsIII in the cultured MSCs was, via altering Bcl-2 family proteins and by involving intrinsic pathway. Conclusion: iAsIII 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.

  11. 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

    Directory of Open Access Journals (Sweden)

    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

  12. MYC/BCL2 protein coexpression contributes to the inferior survival of activated B-cell subtype of diffuse large B-cell lymphoma and demonstrates high-risk gene expression signatures

    DEFF Research Database (Denmark)

    Hu, Shimin; Xu-Monette, Zijun Y; Tzankov, Alexander;

    2013-01-01

    , cyclophosphamide, doxorubicin, vincristine, and prednisone). We show that MYC/BCL2 protein coexpression occurred significantly more commonly in the ABC subtype. Patients with the ABC or GCB subtype of DLBCL had similar prognoses with MYC/BCL2 coexpression and without MYC/BCL2 coexpression. Consistent...... with the notion that the prognostic difference between the 2 subtypes is attributable to MYC/BCL2 coexpression, there is no difference in gene expression signatures between the 2 subtypes in the absence of MYC/BCL2 coexpression. DLBCL with MYC/BCL2 coexpression demonstrated a signature of marked downregulation...... of genes encoding extracellular matrix proteins, those involving matrix deposition/remodeling and cell adhesion, and upregulation of proliferation-associated genes. We conclude that MYC/BCL2 coexpression in DLBCL is associated with an aggressive clinical course, is more common in the ABC subtype...

  13. Signal transduction mediated by Bid, a pro-death Bcl-2 family proteins, connects the death receptor and mitochondria apoptosis pathways

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Two major apoptosis pathways have been defined in mammalian cells, the Fas/TNF-R1 death receptor pathway and the mitochondria pathway. The Bcl-2 family proteins consist of both anti-apoptosis and pro- apoptosis members that regulate apoptosis, mainly by controlling the release of cytochrome c and other mitochondrial apoptotic events. However, death signals mediated by Fas/TNF-R1 receptors can usually activate caspases directly, bypassing the need for mitochondria and escaping the regulation by Bcl-2 family proteins. Bid is a novel pro-apoptosis Bcl-2 family protein that is activated by caspase 8 in response to Fas/TNF-R1 death receptor signals. Activated Bid is translocated to mitochondria and induces cytochrome c release, which in turn activates downstream caspases. Such a connection between the two apoptosis pathways could be important for induction of apoptosis in certain types of cells and responsible for the pathogenesis of a number of human diseases.

  14. Isolation and identification of proteins binding to the major breakpoint region(mbr) of bcl2 gene

    Institute of Scientific and Technical Information of China (English)

    Nan Yang; Yujie Sun; Changyan Ma

    2009-01-01

    Objective: We have previously found that mbr is a regulatory element of the bcl2 gene. The objective of this study is to isolate and identify the proteins binding to the 37 mbr in the 3 '-end of the mbr. Methods: Streptavidin magnetic particles were ligated to concatameric oligonucleofides of 37 mbr and incubated with the nuclear extracts of Jurkat cells. The DNA-binding proteins were eluted and then resolved by SDS-PAGE. After silver staining, the protein bands were excised and subjected to MALDI-TOF MS. Results: Several protein bands were detected after the isolation with magnetic particles, and Splicing factor, proline-and glutamine-rich(SFPQ), Poly(ADP-ribose)polymerase I(PARP), and promyelocytic leukemia protein(PML) were identified by MALDI-TOF MS. Conclusion: Several proteins were isolated and identified from the 37 mbr-protein complex. Results of this study establish a foundation for further study of the mechanisms by which mbr executes its regulatory function.

  15. Serum Bcl-2 concentrations in overweight-obese subjects with nonalcoholic fatty liver disease

    Institute of Scientific and Technical Information of China (English)

    Giovanni Tarantino; Francesco Scopacasa; Annamaria Colao; Domenico Capone; Marianna Tarantino; Ernesto Grimaldi; Silvia Savastano

    2011-01-01

    AIM: To shed some light on the relationship between anti-apoptotic serum Bcl-2 concentrations and metabolic status, anthropometric parameters, inflammation indices, and non-alcoholic fatty liver disease severity were investigated in 43 young individuals with fatty liver (FL) and 41 with nonalcoholic steatohepatitis (NASH). METHODS: Circulating levels of Bcl-2 were detected in 84 patients with ultrasonographic findings of "bright liver" and/or hyper-transaminasemia of unknown origin and/or increase in γ-glutamyl-transpeptidase (γ-GT) strictly in the absence of other acute or chronic liver disease, whose age was not advanced, who gave consent to liver biopsy and were then divided on the basis of the histological results into two groups (43 with FL and 41 with NASH). Twenty lean subjects, apparently healthy and young, were chosen as controls.RESULTS: Serum Bcl-2 concentrations were significantly higher in the FL group than in the NASH group. Insulin resistance and γ-GT activity were significantly higher in NASH subjects. Apoptotic hepatocytes were significantly more numerous in NASH patients. NASH patients presented with larger spleens and augmented C-reactive protein (CRP) concentrations than healthy subjects. Steatosis grade at histology was similar in both NASH and FL populations. The number of apoptotic cells was significantly related to anti-apoptotic Bcl-2 protein values in FL patients. Bcl-2 serum levels positively correlated to body mass index (BMI) values (P ≤ 0.0001) but not to age of the population. Triglycerides/HDL ratio correlated well to waist circumference in males (P = 0.0008). γ-GT activity was associated with homeostatic metabolic assessment (HOMA) (P = 0.0003) and with serum ferritin (P = 0.02). Bcl-2 concentrations were not related to either spleen size or CRP values. NASH patients presented a weak negative correlation between lobular inflammation and Bcl-2 levels. A prediction by low values of serum Bcl-2 towards a greater presence of

  16. 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.

  17. Acidosis promotes Bcl-2 family-mediated evasion of apoptosis: involvement of acid-sensing G protein-coupled receptor Gpr65 signaling to Mek/Erk.

    Science.gov (United States)

    Ryder, Christopher; McColl, Karen; Zhong, Fei; Distelhorst, Clark W

    2012-08-10

    Acidosis arises in solid and lymphoid malignancies secondary to altered nutrient supply and utilization. Tumor acidosis correlates with therapeutic resistance, although the mechanism behind this effect is not fully understood. Here we show that incubation of lymphoma cell lines in acidic conditions (pH 6.5) blocks apoptosis induced by multiple cytotoxic metabolic stresses, including deprivation of glucose or glutamine and treatment with dexamethasone. We sought to examine the role of the Bcl-2 family of apoptosis regulators in this process. Interestingly, we found that acidic culture causes elevation of both Bcl-2 and Bcl-xL, while also attenuating glutamine starvation-induced elevation of p53-up-regulated modulator of apoptosis (PUMA) and Bim. We confirmed with knockdown studies that these shifts direct survival decisions during starvation and acidosis. Importantly, the promotion of a high anti- to pro-apoptotic Bcl-2 family member ratio by acidosis renders cells exquisitely sensitive to the Bcl-2/Bcl-xL antagonist ABT-737, suggesting that acidosis causes Bcl-2 family dependence. This dependence appears to be mediated, in part, by the acid-sensing G protein-coupled receptor, GPR65, via a MEK/ERK pathway. PMID:22685289

  18. Homologous recombination in mammalian cells: effect of p53 and Bcl-2 proteins, replication inhibition and ionizing radiations

    International Nuclear Information System (INIS)

    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)

  19. Assessment of expression of selected Bcl-2 family proteins in lymphoid infiltration in patients with B-cell chronic lymphocytic leukaemia treated with nucleoside analogues.

    Directory of Open Access Journals (Sweden)

    Janusz Kłoczko

    2008-12-01

    Full Text Available B-cell chronic lymphocytic leukaemia (B-CLL is characterized by clonal growth and accumulation of mature lymphoid cells due to disturbance in genetically regulated form of cell death called apoptosis. The intrinsic mechanism of apoptosis is controlled by Bcl-2 family proteins. Purine nucleoside analogues induce the apoptosis in cells in a state of quiescence. The aim of the study was to assess expression of selected Bcl-2 family proteins in neoplastic infiltration in bone marrow in patients with B-CLL treated with nucleoside analogues. The study comprised examination of bone marrow obtained routinely by trephine biopsy from 18 patients with B-CLL diagnosed before administration of purine nucleoside analogues treatment and after its completion. Expression of Bcl-2, Bcl-x and Bax proteins was examined. Lymphoid cells in bone marrow were present in all patients before administration of treatment. After treatment in two patients bone marrow was infiltrated in diffuse pattern, whereas other patients presented nodular pattern of infiltration. The difference between stage of infiltration before and after treatment was statistically significant (p<0.002. High percentage of infiltration cells with positive anti Bcl-2 reaction from 42.0% in one patient to 85.33+/-3.06% in four patients before treatment was observed. After treatment percentage of infiltration cells with positive anti Bcl-2 antibody reaction was from 33.0+/-18.38% in two patients to 99.0% in one patient. Positive correlation between stage of infiltration and expression of Bcl-2 protein was confirmed before and after treatment. Such correlations were not observed in case of Bax and Bcl-x. Strong staining of immunohistochemical reaction of cells in lymphoid infiltration with Bcl-2 antibody was confirmed. There was a difference between Bcl-/Bax ratio before and after treatment. Immunohistochemical assessment of expression of Bcl-2 family proteins in cells of lymphoid infiltration in bone

  20. Involvement of BH4 domain of bcl-2 in the regulation of HIF-1-mediated VEGF expression in hypoxic tumor cells.

    Science.gov (United States)

    Trisciuoglio, D; Gabellini, C; Desideri, M; Ragazzoni, Y; De Luca, T; Ziparo, E; Del Bufalo, D

    2011-06-01

    In addition to act as an antiapoptotic protein, B-cell lymphoma (bcl)-2 can also promote tumor angiogenesis. In this context, we have previously demonstrated that under hypoxia bcl-2 promotes hypoxia-inducible factor-1 (HIF-1)-mediated vascular endothelial growth factor (VEGF) expression in melanoma and breast carcinoma. Here, we report on the role of the BH4 domain in bcl-2 functions, by showing that removal of or mutations at the BH4 domain abrogate the ability of bcl-2 to induce VEGF protein expression and transcriptional activity under hypoxia in human melanoma cells. We have also extended this observation to other human tumor histotypes, such as colon, ovarian and lung carcinomas. The involvement of BH4 on HIF-1α protein expression, stability, ubiquitination and HIF-1 transcriptional activity was also demonstrated in melanoma experimental model. Moreover, we validated the role of the BH4 domain of bcl-2 in the regulation of HIF-1/VEGF axis, demonstrating that BH4 peptide is sufficient to increase HIF-1α protein half-life impairing HIF-1α protein ubiquitination, and to enhance VEGF secretion in melanoma cells exposed to hypoxia. Finally, we found that the mechanism by which bcl-2 regulates HIF-1-mediated VEGF expression does not require BH1 and BH2 domains, and it is independent of antiapoptotic and prosurvival function of bcl-2. PMID:21233846

  1. Function of apoptosis and expression of the proteins Bcl-2, p53 and C-myc in the development of gastric cancer

    Institute of Scientific and Technical Information of China (English)

    An Gao Xu; Shao Guang Li; Ji Hong Liu; Ai Hua Gan

    2001-01-01

    @@INTRODUCTION In China ,the incidence and mortality of gastric cancer rank the second among all cancers. Recent development of cancer [1-20].The aim of this study was investigat the insight of apoptosis and bcl-2, p53 and C-myc protein expression in the development of gastric cancer .

  2. 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)

    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 (P1 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 G1-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

  3. Effects of Low Dose Radiation on Tumor Apoptosis, Cell Cycle and Apoptosis-Related Protein Bcl-2 in Tumor-Bearing Mice

    Institute of Scientific and Technical Information of China (English)

    YUHongsheng; SONGAiqin; FEIConghe; WANGZhuomin; QIUWensheng

    2005-01-01

    Objective: To study the effects of low dose radiation (LDR) on tumor apoptosis, cell cycle progression and changes of apoptosis-related protein Bcl-2 in tumor-bearing mice. Methods: Male mice of Kunming strain were implanted subcutaneously with S180 sarcoma cells in the left inguen as an in situ experimental animal model. Seven days later, the mice were subjected to 75 mGy whole-body γ-irradiation.At 24 and 48 h after the irradiation, all mice were sacrificed. The tumor sizes were measured, and tumor cell apoptosis and cell cycle progression were analyzed by flow cytometry. The expression of apoptosisrelated protein Bcl-2 and the apoptotic rate of tumor cells were observed by immunohistochemistry and electron microscopy. Results: Tumors grew significantly slower after LDR (P<0.05). The tumor cells were arrested in G1 phrase and the expression of Bcl-2 protein decreased at 24 h. Apoptotic rate of tumor cells was increased significantly at 48 h after LDR (P<0.01). Conclusion: LDR could cause a Gl-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. Our study provides practical evidence of clinical application to cancer treatment.

  4. 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.

  5. Isolation of novel single-chain Cro proteins targeted for binding to the bcl-2 transcription initiation site by repertoire selection and subunit combinatorics.

    Science.gov (United States)

    Jonas, Kristina; Van Der Vries, Erhard; Nilsson, Mikael T I; Widersten, Mikael

    2005-11-01

    New designed DNA-binding proteins may be recruited to act as transcriptional regulators and could provide new therapeutic agents in the treatment of genetic disorders such as cancer. We have isolated tailored DNA-binding proteins selected for affinity to a region spanning the transcription initiation site of the human bcl-2 gene. The proteins were derived from a single-chain derivative of the lambda Cro protein (scCro), randomly mutated in its recognition helices to construct libraries of protein variants of distinct DNA-binding properties. By phage display-afforded affinity selections combined with recombination of shuffled subunits, protein variants were isolated, which displayed high affinity for the target bcl-2 sequence, as determined by electrophoretic mobility shift and biosensor assays. The proteins analyzed were moderately sequence-specific but provide a starting point for further maturation of desired function.

  6. Caspase Induction and BCL2 Inhibition in Human Adipose Tissue

    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

    2013-01-01

    OBJECTIVE Cell death determines the onset of obesity and associated insulin resistance. Here, we analyze the relationship among obesity, adipose tissue apoptosis, and insulin signaling. RESEARCH DESIGN AND METHODS 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. RESULTS 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. CONCLUSIONS 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. PMID:23193206

  7. Photobiomodulation on Bax and Bcl-2 Proteins and SIRT1/PGC-1α Axis mRNA Expression Levels of Aging Rat Skeletal Muscle

    Directory of Open Access Journals (Sweden)

    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.

  8. The function of apoptosis and protein expression of bcl-2, p53 and C-myc inthe development of gastric cancer

    Institute of Scientific and Technical Information of China (English)

    An Gao Xu; Shao Guang Li; Ji Hong Liu; Ai Hua Gan

    2000-01-01

    AIM To understand the rule and possible function of apoptosis and protein expression of bcl-2, p53 and C-myc in chronic gastritis, gastric ulcer, non-classic proliferation of gastric mucosa and gastric cancer.METHODS Apoptosis was detected by using in situ terminal labelling (TUNEL). The protein expression ofbcl-2, p53 and C-myc was detected by immunohistochemical method.RESULTS The indexes of apoptosis in chronic active gastritis, gastric ulcer, mild and severe non-classicproliferation of gastric mucosa, early and progressive gastric cancer were 16.8%±12.3%, 24.1%±20.0%,19.3%±16.4%, 15.7%±15.2%, 10.1%±9.1% and 6.3%±6.0%, respectively. The index of progressivegastric cancer was lower than that of early gastric cancer and non-classic proliferation of gastric mucosa(P<0.05). The positive rate of bcl-2 protein was 9.4%, 27.6%, 52.9%, 75.0%, 83.3% and 46.7%,respectively. The positive rate of bcl-2 of early gastric cancer was higher than that of progressive gastriccancer. The positive rates of p53 protein of severe non-classic proliferation, early and progressive gastriccancer were 25.0%, 33.3% and 63.3%, respectively. The positive rate of p53 of progressive gastric cancerwas higher than that of early gastric cancer and non-classic proliferation (P<0.05). In Lauren types, theindex of apoptosis, protein expression rates of bcl-2, p53 and C-myc of intestinal type were 8.3%±7.2%,38.9%, 77.7% and 56.6%, while that of diffuse type were 5.1%±4.9%, 58.3%, 50.0% and 8.3%,respectively. All markers had statistical difference between two types (P<0.05).CONCLUSION Apoptosis was inhibited stepwise in the development of non-classic proliferation of gastricmucosa to early gastric cancer and then to progressive gastric cancer. The high expression of bcl-2, p53 andC-myc was related to the development of gastric cancer, bcl-2 might play an important role in early gastriccancer while p53 and C-myc act mostly in middle and late stage gastric cancer. The Lauren typing of

  9. Plumbagin reduces chronic lymphocytic leukemia cell survival by downregulation of Bcl-2 but upregulation of the Bax protein level.

    Science.gov (United States)

    Fu, Chunling; Gong, Yanqing; Shi, Xuanxuan; Sun, Zengtian; Niu, Mingshan; Sang, Wei; Xu, Linyan; Zhu, Feng; Wang, Ying; Xu, Kailin

    2016-09-01

    Chronic lymphocytic leukemia (CLL) is the most common leukemia in Western countries, and mainly originates from an accumulation of abnormal B cells caused by the dysregulation of cell proliferation and apoptosis rates. The aberration of apoptosis-related genes in CLL cells results in defective apoptosis of CLL cells in response to traditional therapeutic medicine. Plumbagin (5-hydroxy-2-methyl-1, 4-naphthoquinone), a natural compound from Plumbago zeylinica, has been shown to exhibit pro-apoptotic activities in tumor cells. In the present study, we report that plumbagin effectively inhibited CLL cell viability with a lower dose compared to fludarabine, and inhibited cell proliferation in a dose-dependent manner. In addition, plumbagin promoted accumulation of MEC-1 cells in the S phase, and blocked cell cycle transition of HG3 cells from G0/G1 to S phase. Molecularly, plumbagin markedly induced CLL cell apoptosis through reduction of Bcl-2, but through an increase in the Bax protein level. These results suggest that plumbagin may be considered as a potential anticancer agent for CLL therapy. PMID:27461100

  10. Effect of Bcl-2 rs956572 polymorphism on age-related gray matter volume changes.

    Directory of Open Access Journals (Sweden)

    Mu-En Liu

    Full Text Available The anti-apoptotic protein B-cell CLL/lymphoma 2 (Bcl-2 gene is a major regulator of neural plasticity and cellular resilience. Recently, the Bcl-2 rs956572 single nucleotide polymorphism was proposed to be a functional allelic variant that modulates cellular vulnerability to apoptosis. Our cross-sectional study investigated the genetic effect of this Bcl-2 polymorphism on age-related decreases in gray matter (GM volume across the adult lifespan. Our sample comprised 330 healthy volunteers (191 male, 139 female with a mean age of 56.2±22.0 years (range: 21-92. Magnetic resonance imaging and genotyping of the Bcl-2 rs956572 were performed for each participant. The differences in regional GM volumes between G homozygotes and A-allele carriers were tested using optimized voxel-based morphometry. The association between the Bcl-2 rs956572 polymorphism and age was a predictor of regional GM volumes in the right cerebellum, bilateral lingual gyrus, right middle temporal gyrus, and right parahippocampal gyrus. We found that the volume of these five regions decreased with increasing age (all P<.001. Moreover, the downward slope was steeper among the Bcl-2 rs956572 A-allele carriers than in the G-homozygous participants. Our data provide convergent evidence for the genetic effect of the Bcl-2 functional allelic variant in brain aging. The rs956572 G-allele, which is associated with significantly higher Bcl-2 protein expression and diminished cellular sensitivity to stress-induced apoptosis, conferred a protective effect against age-related changes in brain GM volume, particularly in the cerebellum.

  11. 视网膜母细胞瘤Bcl-2和Bax基因蛋白质表达%Expression of Bcl-2 and Bax gene protein in retinoblastoma

    Institute of Scientific and Technical Information of China (English)

    张小猛; 庞利民; 张晓光

    2000-01-01

    目的:研究凋亡及凋亡调控基因Bcl-2/Bax和视网膜母细胞瘤(Retinoblastoma,RB)的发生、发展及退化的关系.方法:收集36例RB标本,对其分别进行Bcl-2和Bax基因的蛋白质免疫组织化学染色.对其表达情况和染色强度进行观察.结果:①Bcl-2在分化型RB中表达比较好;②Bax在未分化型和分化型中表达都比较好.结论:①分化型和未分化型RB中都有Bcl-2/Bax基因蛋白表达;②随RB恶性度的增加,Bcl-2的表达逐渐减弱;Bax的表达无明显改变.③分化型RB受Bcl-2和Bax基因共同控制;未分化型RB受Bax基因调控,Bcl-2基因发挥很少的作用.

  12. Cyanide-induced Death of Dopaminergic Cells is Mediated by Uncoupling Protein-2 Up-regulation and Reduced Bcl-2 Expression

    OpenAIRE

    Zhang, X.; Li, L.; Zhang, L.; Borowitz, J.L.; Isom, G.E.

    2009-01-01

    Cyanide is a potent inhibitor of mitochondrial oxidative metabolism and produces mitochondria-mediated death of dopaminergic neurons and sublethal intoxications are associated with a Parkinson-like syndrome. Cyanide toxicity is enhanced when mitochondrial uncoupling is stimulated following up-regulation of uncoupling protein-2 (UCP-2). In this study, the role of a pro-survival protein, Bcl-2, in cyanide-mediated cell death was determined in a rat dopaminergic immortalized mesencephalic cell l...

  13. Studies on Cytotoxicity of Glaucocalyxin A, C and Its Relation with Bcl-2 Protein%蓝萼甲、丙素细胞毒活性及其与Bcl-2蛋白关系的研究

    Institute of Scientific and Technical Information of China (English)

    嵇源源; 高立文; 张健; 王剑文

    2013-01-01

    目的:研究蓝萼甲素(GLA)和蓝萼丙素(GLC)对15株不同类型的肿瘤细胞的细胞毒性差异以及与Bcl-2蛋白的关系.方法:采用MTT法检测细胞存活率;用Western Blotting检测细胞凋亡关键蛋白Bcl-2的表达;应用分子对接Autodock程序,将GLA和GLC与Bcl-2蛋白进行分子对接,比较其结合的差异性.结果:用MTT法结果表明GLA对所选用的15株肿瘤细胞均有显著的抑制作用,而相同浓度的GLC对15株肿瘤细胞的生存率没有影响;用分子对接法结果显示GLA与Bcl-2蛋白的结合自由能和ki值均低于GLC.结论:GLA更易与Bcl-2蛋白结合从而抑制Bcl-2蛋白的功能,促进细胞凋亡.

  14. Evidence that inhibition of BAX activation by BCL-2 involves its tight and preferential interaction with the BH3 domain of BAX

    Institute of Scientific and Technical Information of China (English)

    Bonsu Ku; Chengyu Liang; Jae U Jung; Byung-Ha Oh

    2011-01-01

    Interactions between the BCL-2 family proteins determine the cell's fate to live or die. How they interact with each other to regulate apoptosis remains as an unsettled central issue. So far, the antiapoptotic Bc1-2 proteins are thought to interact with BAX weakly, but the physiological significance of this interaction has been vague.Herein, we show that recombinant BCL-2 and BCL-w interact potently with a BCL-2 homology (BH) 3 domain-containing peptide derived from BAX, exhibiting the dissociation constants of 15 and 23 nM, respectively. To clarify the basis for this strong interaction, we determined the three-dimensional structure of a complex of BCL-2 with a BAX peptide spanning its BH3 domain. It revealed that their interactions extended beyond the canonical BH3 domain and involved three nonconserved charged residues of BAX. A novel BAX variant, containing the alanine substitution of these three residues, had greatly impaired affinity for BCL-2 and BCL-w, hut was otherwise indistinguishable from wild-type BAX. Critically, the apoptotic activity of the BAX variant could not be restrained by BCL-2 and BCL-w, pointing that the observed tight interactions are critical for regulating BAX activation. We also comprehensively quantified the binding affinities between the three BCL-2 subfamily proteins. Collectively, the data show that due to the high affinity of BAX for BCL-2, BCL-w and A1, and of BAK for BCL-XL, MCL-1 and A1, only a subset of BH3-only proteins, commonly including BIM, BID and PUMA, could he expected to free BAX or BAK from the antiapoptotic BCL-2 proteins to elicit apoptosis.

  15. Two independent positive feedbacks and bistability in the Bcl-2 apoptotic switch.

    Directory of Open Access Journals (Sweden)

    Jun Cui

    Full Text Available BACKGROUND: The complex interplay between B-cell lymphoma 2 (Bcl-2 family proteins constitutes a crucial checkpoint in apoptosis. Its detailed molecular mechanism remains controversial. Our former modeling studies have selected the 'Direct Activation Model' as a better explanation for experimental observations. In this paper, we continue to extend this model by adding interactions according to updating experimental findings. METHODOLOGY/PRINCIPAL FINDINGS: Through mathematical simulation we found bistability, a kind of switch, can arise from a positive (double negative feedback in the Bcl-2 interaction network established by anti-apoptotic group of Bcl-2 family proteins. Moreover, Bax/Bak auto-activation as an independent positive feedback can enforce the bistability, and make it more robust to parameter variations. By ensemble stochastic modeling, we also elucidated how intrinsic noise can change ultrasensitive switches into gradual responses. Our modeling result agrees well with recent experimental data where bimodal Bax activation distributions in cell population were found. CONCLUSIONS/SIGNIFICANCE: Along with the growing experimental evidences, our studies successfully elucidate the switch mechanism embedded in the Bcl-2 interaction network and provide insights into pharmacological manipulation of Bcl-2 apoptotic switch as further cancer therapies.

  16. Bcl-2 family members inhibit oxidative stress-induced programmed cell death in Saccharomyces cerevisiae.

    Science.gov (United States)

    Chen, Shao-Rong; Dunigan, David D; Dickman, Martin B

    2003-05-15

    Selected antiapoptotic genes were expressed in baker's yeast (Saccharomyces cerevisiae) to evaluate cytoprotective effects during oxidative stress. When exposed to treatments resulting in the generation of reactive oxygen species (ROS), including H(2)O(2), menadione, or heat shock, wild-type yeast died and exhibited apoptotic-like characteristics, consistent with previous studies. Yeast strains were generated expressing nematode ced-9, human bcl-2, or chicken bcl-xl genes. These transformants tolerated a range of oxidative stresses, did not display features associated with apoptosis, and remained viable under conditions that were lethal to wild-type yeast. Yeast strains expressing a mutant antiapoptotic gene (bcl-2 deltaalpha 5-6), known to be nonfunctional in mammalian cells, were unable to tolerate any of the ROS-generating insults. These data are the first report showing CED-9 has cytoprotective effects against oxidative stress, and add CED-9 to the list of Bcl-2 protein family members that modulate ROS-mediated programmed cell death. In addition, these data indicate that Bcl-2 family members protect wild-type yeast from physiological stresses. Taken together, these data support the concept of the broad evolutionary conservation and functional similarity of the apoptotic processes in eukaryotic organisms.

  17. Up-regulation of Bcl-2 is required for the progression of prostate cancer cells from an androgen-dependent to an androgen-independent growth stage

    Institute of Scientific and Technical Information of China (English)

    Yuting Lin; Junichi Fukuchi; Richard A Hiipakka; John M Kokontis; Jialing Xiang

    2007-01-01

    Bcl-2 is an anti-apoptotic oncoprotein and its protein levels are inversely correlated with prognosis in many cancers.However, the role of Bcl-2 in the progression of prostate cancer is not clear. Here we report that Bcl-2 is required for the progression of LNCaP prostate cancer cells from an androgen-dependent to an androgen-independent growth stage. The mRNA and protein levels of Bcl-2 are significantly increased in androgen-independent prostate cancer cells, shRNA-mediated gene silencing of Bcl-2 in androgen-independent prostate cancer cells promotes UV-induced apoptosis and suppresses the growth of prostate tumors in vivo. Growing androgen-dependent cells under androgen-deprivation conditions results in formation of androgen-independent colonies; and the transition from androgen-dependent to androgen-independent growth is blocked by ectopic expression of the Bcl-2 antagonist Bax or Bcl-2 shRNA. Thus, our results demonstrate that Bcl-2 is not only critical for the survival of androgen-independent prostate cancer cells, but is also required for the progression of prostate cancer cells from an androgen-dependent to an androgen-independent growth stage.

  18. Bcl-2 over-expression and activation of protein kinase C suppress the Trail-induced apoptosis in Jurkat T cells

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Trail,a tumor necrosis factor-related apoptosis-inducing ligand,is a novel potent endogenous activator of the cell death pathway through the activation of cell surface death receptors Trail-R1 and Trail-R2.Its role,like FasL in activation-induced cell death(AICD),has been demonstrated in immune system.However the mechanism of Trail induced apoptosis remains unclear.In this report,the recombinant Trail protein was expressed and purified.The apoptosis-inducing activity and the regulation mechanism of recombinant Trail on Jurkat T cells were explored in vitro.Trypan blue exclusion assay demonstrated that the recombinant Trail protein actively killed Jurkat T cells in a dose-dependent manner.Trail-induced apoptosis in Jurkat T cells were remarkably reduced by Bcl-2 over expression in Bcl-2 gene transfected cells.Treatment with PMA(phorbol 12-myristate 13-acetate),a PKC activator,suppressed Trail-induced apoptosis in Jurkat T cells.The inhibition of apoptosis by PMA was abolished by pretreatment with Bis,a PKC inhibitor.Taken together,it was suggested that Bcl-2 over-expression and PMA activated PKC actively down-regulated the Trail-mediated apoptosis in Jurkat T cell.

  19. ABT-737 reverses the acquired radioresistance of breast cancer cells by targeting Bcl-2 and Bcl-xL

    OpenAIRE

    Li Ji-Yu; Li Yu-Yang; Jin Wei; Yang Qing; Shao Zhi-Ming; Tian Xing-Song

    2012-01-01

    Abstract Background Acquired radioresistance of cancer cells remains a fundamental barrier to attaining the maximal efficacy of radiotherapy for the treatment of breast cancer. Anti-apoptotic proteins, such as Bcl-2 and Bcl-xL, play an important role in the radioresistance of cancer cells. In the present study, we aimed to determine if ABT-737, a BH3-only mimic, could reverse the acquired radioresistance of the breast cancer cell line MDA-MB-231R by targeting Bcl-2 and Bcl-xL. Methods The rad...

  20. Effects of fluoride on liver apoptosis and Bcl-2, Bax protein expression in freshwater teleost, Cyprinus carpio.

    Science.gov (United States)

    Cao, Jinling; Chen, Jianjie; Wang, Jundong; Jia, Ruhui; Xue, Wenjuan; Luo, Yongju; Gan, Xi

    2013-05-01

    Fish take up fluoride directly from water and are the target organisms for fluoride pollution in the aquatic ecosystems. This study was conducted to evaluate oxidative stress, histopathological changes, apoptosis and Bcl-2, Bax expression in the livers of the common carp (Cyprinus carpio) chronically exposed to fluoride. Our results showed that after 90 d of exposure, the inhibition of SOD, GSH activities and a dose-dependent stimulation of MDA levels in the liver tissues indicated that fluoride caused oxidative stress in the fish. Microscopic examinations showed that damages to the liver tissues and cell organelles in the liver tissues increased with exposure concentration. A positive correlation was observed between the apoptosis index and fluoride levels in the livers (r=0.995). There was a negative correlation between the fluoride concentration of water and the expression of Bcl-2, Bcl-2/Bax (r=-0.98, r=-0.96). A positive correlation was showed between the fluoride concentration of water and the expression of Bax (r=0.96) after 90 d of exposure. Our results suggested that the common carp could tolerate relatively high levels of fluoride but adverse effects of fluoride occurred in the livers of the fish after 90 d of exposure. The apoptosis of liver cells had an important causative role in the process of fluoride-induced pathological changes of liver. PMID:23415306

  1. Deregulation of apoptosis mediators' p53 and bcl2 in lung tissue of COPD patients

    Directory of Open Access Journals (Sweden)

    Pentilas Nikolaos

    2010-04-01

    Full Text Available Abstract Abnormal apoptotic events in chronic obstructive pulmonary disease (COPD subvert cellular homeostasis and may play a primary role in its pathogenesis. However, studies in human subjects are limited. p53 and bcl2 protein expression was measured by western blot on lung tissue specimens from 43 subjects (23 COPD smokers and 20 non-COPD smokers, using beta-actin as internal control. Additionally, p53 and bcl2 expression patterns were evaluated by immunohistochemistry in formalin-fixed, paraffin-embedded lung tissue sections from the same individuals. Western blot analysis showed statistically significant increased p53 protein levels in COPD smokers in comparison with non-COPD smokers (p = 0.038, while bcl2 protein levels were not statistically different between the two groups. Lung immunohistochemistry showed increased ratio of positive p53-stained type II pneumocytes/total type II pneumocytes in COPD smokers compared to non-COPD smokers (p = 0.01, whereas the p53 staining ratio in alveolar macrophages and in lymphocyte-like cells did not differ statistically between the two groups. On the other hand, bcl2 expression did not differ between the two groups in all three cell types. The increased expression of pro-apoptotic p53 in type II pneumocytes of COPD patients not counterbalanced by the anti-apoptotic bcl2 could reflect increased apoptosis in the alveolar epithelium of COPD patients. Our results confirm previous experiments and support the hypothesis of a disturbance in the balance between the pro- and anti-apoptotic mediators in COPD.

  2. THE EXPERIMENTAL STUDY ON THE CELL APOPTOSIS AND EXPRESSION OF BCL-2 PROTEIN IN INTRACEREBRAL HEMORRHAGE IN MODEL OF RATS

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Intra-cerebral hemorrhage is a common clinicaldisease,with a high mortality and morbidity.So itis one of the clinical hot topics.It has been foundinrecent years that there is a close relationship bet weenthe cell apoptosis and the course or prognosis of in-tra-cerebral hemorrhage.Bcl-2,as the apoptosis-adjusted gene,plays ani mportant role in the courseof cell apoptosis,but the mechanis min the cell ap-optosis in intra-cerebral hemorrhage remains un-clear.In this experi ment,with the model buildingof the in...

  3. Association of BCL2-938C>A genetic polymorphism with glioma risk in Chinese Han population.

    Science.gov (United States)

    Li, Wei; Qian, Chunfa; Wang, Linxiong; Teng, Hong; Zhang, Li

    2014-03-01

    Glioma is the most common type of primary brain malignancy in adults. The anti-apoptotic protein B-cell lymphoma 2 (BCL2) has been implicated in the pathogenesis of glioma. This study aimed to evaluate the potential association between BCL2-938C>A genetic polymorphism and glioma susceptibility. This case-control study was conducted in Chinese Han populations consisting of 248 glioma cases and 252 cancer-free controls. The BCL2-938C>A genetic polymorphism was detected by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and verified using DNA sequencing methods. Our data suggested that the genotype/allele of BCL2-938C>A polymorphism were statistically associated with the increased risk of glioma where the risk of glioma for genotype AA or allele A is significantly higher than wild genotype CC (odds ratio (OR) = 2.23, 95% confidence interval (CI) 1.21-4.10, p = 0.009) or allele C (OR = 1.39, 95% CI 1.06-1.82, p = 0.016), respectively. In addition, the BCL2-938AA genotype was significantly more common in patients with glioblastoma and in patients with grade IV glioma. Our findings indicate that the BCL2-938C>A polymorphism is associated with the susceptibility to glioma in Chinese Han populations and might be used as molecular markers for evaluating glioma risk.

  4. Modulated Binding of SATB1, a Matrix Attachment Region Protein, to the AT-Rich Sequence Flanking the Major Breakpoint Region of BCL2

    Science.gov (United States)

    Ramakrishnan, Meera; Liu, Wen-Man; DiCroce, Patricia A.; Posner, Aleza; Zheng, Jian; Kohwi-Shigematsu, Terumi; Krontiris, Theodore G.

    2000-01-01

    The t(14,18) chromosomal translocation that occurs in human follicular lymphoma constitutively activates the BCL2 gene and disrupts control of apoptosis. Interestingly, 70% of the t(14,18) translocations are confined to three 15-bp clusters positioned within a 150-bp region (major breakpoint region or [MBR]) in the untranslated portion of terminal exon 3. We analyzed DNA-protein interactions in the MBR, as these may play some role in targeting the translocation to this region. An 87-bp segment (87MBR) immediately 3′ to breakpoint cluster 3 was essential for DNA-protein interaction monitored with mobility shift assays. We further delineated a core binding region within 87MBR: a 33-bp, very AT-rich sequence highly conserved between the human and mouse BCL2 gene (37MBR). We have purified and identified one of the core factors as the matrix attachment region (MAR) binding protein, SATB1, which is known to bind to AT-rich sequences with a high propensity to unwind. Additional factors in nuclear extracts, which we have not yet characterized further, increased SATB1 affinity for the 37MBR target four- to fivefold. Specific binding activity within 37MBR displayed cell cycle regulation in Jurkat T cells, while levels of SATB1 remained constant throughout the cell cycle. Finally, we demonstrated in vivo binding of SATB1 to the MBR, strongly suggesting the BCL2 major breakpoint region is a MAR. We discuss the potential consequences of our observations for both MBR fragility and regulatory function. PMID:10629043

  5. Apoptosis of Hepatoma Cell Line HepG2 Induced by the Combination of Radiotherapy and Thermotherapy and Its Relationship with Bcl-2/Bax Protein Expressions%放疗联合热疗诱导肝癌HepG2细胞凋亡及其与Bcl-2和Bax蛋白表达关系的研究

    Institute of Scientific and Technical Information of China (English)

    张力; 龚明玉; 李毅学; 张立广; 王兴艳

    2011-01-01

    Objective To explore the apoptosis of hepatoma cell line HepG2 induced by the combination of radiotherapy and thermotherapy and its relationship with Bcl - 2/Bax protein expressions. Methods In vitro cultured HepG2 cells were randomly divided into four groups: control group ( not treated ), radiotherapy group, thermotherapy group, and combination group. The apoptosis of HepG2 cells were detected by flow cytometry. The expressions of the apoptosis-related proteins of Bcl-2 and Bax were detected by immunohistochemical methods. Results The apoptosis rates of HepG2 cells were significantly different among these four groups ( P < 0. 05 ). The apoptosis rates were significantly higher in radiotherapy group, thermotherapy group, and combination group than in control group ( P <0. 05 ). It was also significantly higher in combination group than in radiotherapy group and thermotherapy group ( P < 0. 05 ). The expressions of Bcl-2 and Bax and the Bax/Bcl-2 ratio were also significantly different among these four groups ( P <0. 05 ). The expression of Bcl -2 protein were significantly decreased and the expression of Bax protein significantly increased in radiotherapy group, thermotherapy group, and combination group than in control group ( both P < 0. 05 ), and the Bax/Bcl - 2 ratio was also significantly increased ( P < 0. 05 ). The expression of Bcl - 2 protein were significantly decreased and the expression of Bax protein significantly increased in combination group than in radiotherapy group and thermotherapy group ( both P < 0. 05 ), and the Bax/Bcl - 2 ratio was also significantly increased ( P < 0. 05 ). Conclusion The combination of radiotherapy and thermotherapy can more effectively induce the apoptosis of HepG2, and it may be achieved by inhibiting the expression of Bcl - 2 protein and promoting the expression of Bax protein.%目的 探讨放疗联合热疗诱导人肝癌HepG2细胞凋亡及其与Bcl-2和Bax蛋白表达的关系.方法

  6. C57/BL6小鼠海马发育和老化过程中Bcl-2及Bax的表达%Expression of Bcl-2 and Bax protein in the development and aging of C57/BL6 mouse hippocampus

    Institute of Scientific and Technical Information of China (English)

    李潮; 张敬坤; 张莉

    2011-01-01

    目的 观察C57/BL6小鼠海马发育老化过程中Bcl-2、Bax蛋白的表达变化.方法 取不同胚龄(embryonic day,E)、生后(postnatal day,P)日龄或月龄的小鼠海马,应用免疫组化及图像分析技术检测Bcl 2和Bax蛋白的表达.结果 E16 d~P7 d,海马CA区锥体细胞层和齿状回颗粒细胞层Bcl 2和Bax阳性细胞均逐渐增多,平均吸光度( average optical,AO)值逐渐增大;P14 d~P21 d阳性细胞逐渐减少,CA区AO值逐渐减小,齿状回AO值先增大后减小;P28 d后趋于稳定.CA区Bcl 2/Bax比值E16 d~E20 d增大,P1 d减小,P3 d~P5 d增大,P7 d~P21 d减小;以后趋于稳定.齿状回Bcl 2/Bax比值只在P1 d降低.结论 Bcl-2和Bax蛋白可能与小鼠海马发育和老化过程中的形态学变化密切相关.%Objective To observe the changes of expression of Bcl-2 and Bax protein in the development and aging of C57/BL6 mouse hippocampus. Methods Immunohistochemical and image analysis methods were used to detect the expression of Bcl-2 and Bax protein in the mouse hippocampus of different age. Results From embyronic (E) 16 day (d) to postnatal day (P) 7 d, Bcl-2 and Bax immunoreactive cells increased in the pyramidal layer and granular layer, and the average optical (AO) increased too. From P14 d to P21 d, immunoreactive cells decreased, and their AO decreased gradually in the CA area; AO increased first but then decreased in dentate gyrus. On P28 d, the immunoreactive cells and their AO were unchanged. Moreover, the ratio of Bcl-2/Bax rose on E16 d to E20 d, diminished on P1 d, increased on P3 d to P5 d, and decreased on P7 d to P21 d. Then the ratio of Bcl-2/ Bax remained unchanged after P28 d. Conclusion Bcl-2 and Bax protein may be correlated with the morphological changes in the development and aging of mouse hippocampus.

  7. Combining a BCL2 Inhibitor with the Retinoid Derivative Fenretinide Targets Melanoma Cells Including Melanoma Initiating Cells

    OpenAIRE

    Mukherjee, Nabanita; Reuland, Steven N.; Lu, Yan; Luo, Yuchun; Lambert, Karoline; Fujita, Mayumi; Robinson, William A.; Robinson, Steven E.; David A Norris; Yiqun G Shellman

    2014-01-01

    Investigations from multiple laboratories support the existence of melanoma initiating cells (MICs) that potentially contribute to melanoma's drug resistance. ABT-737, a small molecule BCL-2/BCL-XL/BCL-W inhibitor, is promising in cancer treatments, but not very effective against melanoma, with the anti-apoptotic protein MCL-1 as the main contributor to resistance. The synthetic retinoid fenretinide (4-HPR) has shown promise for treating breast cancers. Here, we tested whether the combination...

  8. 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.

  9. Inhibitory effect and affect on Bcl-2 and Bax protein expression of renal cancer prescription No.1 in mice with renal cancer%解氏肾癌一号方对小鼠肾癌的抑制作用及对Bcl-2和Bax蛋白表达的影响

    Institute of Scientific and Technical Information of China (English)

    朱成功; 崔佳; 赵莹莹; 解建国

    2015-01-01

    Objective To investigate inhibitory effect and affect on Bcl-2 and Bax protein expression of renal cancer prescription No.1 in mice with renal cancer. Methods The animal models of renal cancer were established and divided into saline control group,Chinese medicine control group,interleukin-2 group and renal cancer prescription NO.1 group. Inhibitory rate of tumor in four groups was calculated and the apoptosis-related protein Bcl-2 and Bax index were de-tected by immuno- histochemistry. Results The inhibitory rate of tumor in renal cancer prescription NO.1 group was higher than that in saline control group and interleukin-2 group respectively,and the weight of mice was increased.The expression of Bcl-2 in renal cancer prescription NO.1 group was lower,but expression of Bax in renal cancer prescrip-tion NO.1 group was higher. Conclusion Renal cancer prescription NO.1 can inhibit the expression of Bcl-2,raise the expression of Bax,and suppress tumor growth,improve the quality of life in mice.%目的:探讨解氏肾癌一号方对小鼠肾癌的抑制作用及对Bcl-2和Bax蛋白表达的影响。方法建立肾癌小鼠动物模型,分为生理盐水对照组、中药对照组、白介素-2组、解氏肾癌一号方组,计算各组抑瘤率以及采用免疫组化法检测凋亡相关蛋白Bcl-2和Bax的表达。结果解氏肾癌一号方组抑瘤率高于生理盐水对照组及白介素-2组,小鼠体重增加。解氏肾癌一号方组小鼠肿瘤组织Bcl-2表达下调,Bax表达上调。结论解氏肾癌一号方可以下调Bcl-2的表达,上调Bax的表达,从而抑制肿瘤生长,改善小鼠的生存质量。

  10. Effect of medroxyprogesterone acetate on K562/AO2 cells and P - gp, Bcl - 2 resistance protein expression%甲孕酮对K562/AO2细胞及P-gp、Bcl-2耐药蛋白表达的影响

    Institute of Scientific and Technical Information of China (English)

    王双

    2014-01-01

    Objective:To investigate the effect of MPA on leukemia K562 / AO2 cell apoptosis rate and expression of P -gp,Bcl - 2 resistance protein. Methods:To inhibit the proliferation of tumor cells was detected by MTT rate,to detect the ex-pression of P - gp and Bcl - 2 tumor cell apoptosis,flow cytometry. Results:MPA can improve the K562 / AO2 cell apoptosis, downregulate the expression of K562 / AO2 cells P - gp,Bcl - 2. Conclusion:MPA can improve the chemotherapeutic sensitivi-ty of K562 / AO2 cell,promote the apoptosis of reversal of multidrug resistance,have certain effect on K562 / AO2 cells.%目的:探讨甲孕酮对白血病 K562/ AO2细胞凋亡率及 P - gp、Bcl -2耐药蛋白表达的影响。方法以 MTT法检测肿瘤细胞增殖的抑制率,流式细胞术检测肿瘤细胞凋亡、P - gp 及 Bcl -2表达。结果甲孕酮能够提高 K562/AO2细胞的凋亡,能够下调 K562/ AO2细胞 P - gp、Bcl -2的表达。结论甲孕酮能提高 K562/ AO2细胞化疗敏感性,促进其凋亡,对 K562/ AO2细胞有一定的逆转耐药作用。

  11. Thioflavin S (NSC71948) interferes with Bcl-2-associated athanogene (BAG-1)-mediated protein-protein interactions.

    Science.gov (United States)

    Sharp, Adam; Crabb, Simon J; Johnson, Peter W M; Hague, Angela; Cutress, Ramsey; Townsend, Paul A; Ganesan, A; Packham, Graham

    2009-11-01

    The C-terminal BAG domain is thought to play a key role in BAG-1-induced survival and proliferation by mediating protein-protein interactions, for example, with heat shock proteins HSC70 and HSP70, and with RAF-1 kinase. Here, we have identified thioflavin S (NSC71948) as a potential small-molecule chemical inhibitor of these interactions. NSC71948 inhibited the interaction of BAG-1 and HSC70 in vitro and decreased BAG-1:HSC70 and BAG-1:HSP70 binding in intact cells. NSC71948 also reduced binding between BAG-1 and RAF-1, but had no effect on the interaction between two unrelated proteins, BIM and MCL-1. NSC71948 functionally reversed the ability of BAG-1 to promote vitamin D3 receptor-mediated transactivation, an activity of BAG-1 that depends on HSC70/HSP70 binding, and reduced phosphorylation of p44/42 mitogen-activate protein kinase. NSC71948 can be used to stain amyloid fibrils; however, structurally related compounds, thioflavin T and BTA-1, had no effect on BAG-1:HSC70 binding, suggesting that structural features important for amyloid fibril binding and inhibition of BAG-1:HSC70 binding may be separable. We demonstrated that NSC71948 inhibited the growth of BAG-1 expressing human ZR-75-1 breast cancer cells and wild-type, but not BAG-1-deficient, mouse embryo fibroblasts. Taken together, these data suggest that NSC71948 may be a useful molecule to investigate the functional significance of BAG-1 C-terminal protein interactions. However, it is important to recognize that NSC71948 may exert additional "off-target" effects. Inhibition of BAG-1 function may be an attractive strategy to inhibit the growth of BAG-1-overexpressing cancers, and further screens of additional compound collections may be warranted.

  12. Comparative study of Bax, Bcl-2 protein expression in villi structure during normal pregnancy and missed abortion%正常早孕与稽留流产绒毛组织结构中Bax和Bcl-2蛋白表达的对比研究

    Institute of Scientific and Technical Information of China (English)

    杨兴爽

    2014-01-01

    Objective To study apoptosis regulating proteins Bcl-2 and Bax in normal pregnancy and missed abortion villi structure and its significance, and explore the reasons for missed abortion. Methods Choose our hospital patients missed abortion and early pregnancy abortion patients, 60 cases in total, divided into group A and group B. Immediately after abortion, embryonic villi specimens sent to pathology. Light microscopy were applied in each group villi morphological changes in the structure, while applying immunohistochemical methods and computer image analysis system to detect Bax, Bcl-2 expression in each group villi and cell apoptosis. Results Missed abortion group trophoblast cell apoptosis index was (33.32±0.79)%, was significantly higher in group B(18.90±0.63)%, difference was statistically significant (P<0.01). Bax and Bcl-2 in the two groups syncytiotrophoblast cells show positive rate. In missed abortion group, Bax positive rate increased, Bcl-2 positive rate of decline, Bcl-2/Bax ratio increased, differences were statistically significant (P<0.01). Conclusion The increasing positive expression rate of Bax and the decreasing positive expression rate of Bcl-2 in decidua villi can lead to villous syncytiotrophoblast cells increased significantly,and further lead to missed abortion.%目的:研究凋亡调控蛋白Bcl-2和Bax在正常早孕与稽留流产绒毛组织结构中的表达及其意义,探讨稽留流产原因。方法选择本院就诊的稽留流产患者和早孕人工流产患者各60例,分为A组、B组。流产后立即留取胚胎绒毛组织送病理。分别应用光镜观察各组绒毛组织细胞形态结构的改变;同时应用免疫组织化学方法和计算机图文分析系统检测Bax、Bcl-2在各组绒毛的表达及细胞凋亡情况。结果稽留流产组绒毛滋养细胞中凋亡指数为(33.32±0.79)%,明显高于对照组B组的(18.90±0.63)%,差异有统计学意义(P<0.01)。Bax和Bcl-2在两组合体滋养

  13. Effect of captopril and paraquat on expression of p53 and Bcl-2 genes and proteins in rat lung tissue using RT-PCR and immunohistochemistry

    Directory of Open Access Journals (Sweden)

    Azizi E

    2008-10-01

    Full Text Available "n Normal 0 false false false EN-US X-NONE AR-SA MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:Arial; mso-bidi-theme-font:minor-bidi;} Background: Paraquat is an herbicide produced and used prevalently worldwide. Studies have shown that lung fibrosis induced by paraquat can be prevented or delayed by certain antioxidants, iron chelating agents, melatonin, and, recently, blood pressure lowering drugs such as captopril."n"n Methods: The protective effects of captopril on paraquat toxicity were studied using RT-PCR and immunohistochemistry to determine the gene and protein expression of p53 and Bcl-2 in lung tissue samples from rats treated with captopril before and after exposure to paraquat."n"n Results: We found no significant difference in the gene and protein expression of p53 in different tissue samples, except for mRNA levels in the lung tissue of captopril-treated rats. However, the protein expression of Bcl-2 is greater in tissue from rats exposed to paraquat alone and paraquat together with pre- and posttreatment with captopril compared to tissue from untreated control rats and from those treated with captopril alone, which can be due to inflammatory responses of lung tissue. By RT-PCR, we were unable to detect Bcl-2 in lung tissue samples."n"n Conclusion: These results show that paraquat does not induce significant DNA damage; therefore, the

  14. Influence of Tanshinone IIa on heat shock protein 70, Bcl-2 and Bax expression in rats with spinal ischemia/reperfusion injury

    Institute of Scientific and Technical Information of China (English)

    Li Zhang; Weidong Gan; Guoyao An

    2012-01-01

    Tanshinone IIa is an effective monomer component of Danshen, which is a traditional Chinese medicine for activating blood circulation to dissipate blood stasis. Tanshinone IIa can effectively improve brain tissue ischemia/hypoxia injury. The present study established a rat model of spinal cord ischemia/reperfusion injury and intraperitoneally injected Tanshinone IIa, 0.5 hour prior to model establishment. Results showed that Tanshinone IIa promoted heat shock protein 70 and Bcl-2 protein expression, but inhibited Bax protein expression in the injured spinal cord after ischemia/reperfusion injury. Furthermore, Nissl staining indicated a reduction in nerve cell apoptosis and fewer pathological lesions in the presence of Tanshinone IIa, compared with positive control Danshen injection.

  15. Cannabinoids Regulate Bcl-2 and Cyclin D2 Expression in Pancreatic β Cells.

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    Jihye Kim

    Full Text Available Recent reports have shown that cannabinoid 1 receptors (CB1Rs are expressed in pancreatic β cells, where they induce cell death and cell cycle arrest by directly inhibiting insulin receptor activation. Here, we report that CB1Rs regulate the expression of the anti-apoptotic protein Bcl-2 and cell cycle regulator cyclin D2 in pancreatic β cells. Treatment of MIN6 and βTC6 cells with a synthetic CB1R agonist, WIN55,212-2, led to a decrease in the expression of Bcl-2 and cyclin D2, in turn inducing cell cycle arrest in G0/G1 phase and caspase-3-dependent apoptosis. Additionally, genetic deletion and pharmacological blockade of CB1Rs after injury in mice led to increased levels of Bcl-2 and cyclin D2 in pancreatic β cells. These findings provide evidence for the involvement of Bcl-2 and cyclin D2 mediated by CB1Rs in the regulation of β-cell survival and growth, and will serve as a basis for developing new therapeutic interventions to enhance β-cell function and growth in diabetes.

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

    International Nuclear Information System (INIS)

    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

  17. Prometaphase arrest-dependent phosphorylation of Bcl-2 family proteins and activation of mitochondrial apoptotic pathway are associated with 17α-estradiol-induced apoptosis in human Jurkat T cells.

    Science.gov (United States)

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

    2013-10-01

    In Jurkat T cell clone (JT/Neo), G2/M arrest, apoptotic sub-G1 peak, mitochondrial membrane potential (Δψm) loss, and TUNEL-positive DNA fragmentation were induced following exposure to 17α-estradiol (17α-E2), whereas none of these events (except for G2/M arrest) were induced in Jurkat cells overexpressing Bcl-2 (JT/Bcl-2). Under these conditions, phosphorylation at Thr161 and dephosphorylation at Tyr15 of Cdk1, upregulation of cyclin B1 level, histone H1 phosphorylation, Cdc25C phosphorylation at Thr-48, Bcl-2 phosphorylation at Thr-56 and Ser-70, Mcl-1 phosphorylation, and Bim phosphorylation were detected in the presence of Bcl-2 overexpression. However, the 17α-E2-induced upregulation of Bak levels, activation of Bak, activation of caspase-3, and PARP degradation were abrogated by Bcl-2 overexpression. In the presence of the G1/S blocking agent hydroxyurea, 17α-E2 failed to induce G2/M arrest and all apoptotic events including Cdk1 activation and phosphorylation of Bcl-2, Mcl-1 and Bim. The 17α-E2-induced phosphorylation of Bcl-2 family proteins and mitochondrial apoptotic events were suppressed by a Cdk1 inhibitor but not by aurora A and aurora B kinase inhibitors. Immunofluorescence microscopic analysis showed that an aberrant bipolar microtubule array, incomplete chromosome congression at the metaphase plate, and prometaphase arrest, which was reversible, were the underlying factors for 17α-E2-induced mitotic arrest. The in vitro microtubule polymerization assay showed that 17α-E2 could directly inhibit microtubule formation. These results show that the apoptogenic activity of 17α-E2 was due to the impaired mitotic spindle assembly causing prometaphase arrest and prolonged Cdk1 activation, the phosphorylation of Bcl-2, Mcl-1 and Bim, and the activation of Bak and mitochondria-dependent caspase cascade. PMID:23707954

  18. Bcl-2 Retards Cell Cycle Entry through p27Kip1, pRB Relative p130, and Altered E2F Regulation

    OpenAIRE

    Vairo, Gino; Soos, Timothy J.; Upton, Todd M.; Zalvide, Juan; DeCaprio, James A.; Ewen, Mark E.; Koff, Andrew; Adams, Jerry M.

    2000-01-01

    Independent of its antiapoptotic function, Bcl-2 can, through an undetermined mechanism, retard entry into the cell cycle. Cell cycle progression requires the phosphorylation by cyclin-dependent kinases (Cdks) of retinoblastoma protein (pRB) family members to free E2F transcription factors. We have explored whether retarded cycle entry is mediated by the Cdk inhibitor p27 or the pRB family. In quiescent fibroblasts, enforced Bcl-2 expression elevated levels of both p27 and the pRB relative p1...

  19. Structural and functional similarity between the bacterial type III secretion system needle protein PrgI and the eukaryotic apoptosis Bcl-2 proteins.

    Directory of Open Access Journals (Sweden)

    Matthew D Shortridge

    Full Text Available BACKGROUND: 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. METHODOLOGY/PRINCIPAL FINDINGS: 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. CONCLUSIONS/SIGNIFICANCE: 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

  20. Expansion of human and murine hematopoietic stem and progenitor cells ex vivo without genetic modification using MYC and Bcl-2 fusion proteins.

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    Gregory A Bird

    Full Text Available The long-term repopulating hematopoietic stem cell (HSC population can self-renew in vivo, support hematopoiesis for the lifetime of the individual, and is of critical importance in the context of bone marrow stem cell transplantation. The mechanisms that regulate the expansion of HSCs in vivo and in vitro remain unclear to date. Since the current set of surface markers only allow for the identification of a population of cells that is highly enriched for HSC activity, we will refer to the population of cells we expand as Hematopoietic Stem and Progenitor cells (HSPCs. We describe here a novel approach to expand a cytokine-dependent Hematopoietic Stem and Progenitor Cell (HSPC population ex vivo by culturing primary adult human or murine HSPCs with fusion proteins including the protein transduction domain of the HIV-1 transactivation protein (Tat and either MYC or Bcl-2. HSPCs obtained from either mouse bone marrow, human cord blood, human G-CSF mobilized peripheral blood, or human bone marrow were expanded an average of 87 fold, 16.6 fold, 13.6 fold, or 10 fold, respectively. The expanded cell populations were able to give rise to different types of colonies in methylcellulose assays in vitro, as well as mature hematopoietic populations in vivo upon transplantation into irradiated mice. Importantly, for both the human and murine case, the ex vivo expanded cells also gave rise to a self-renewing cell population in vivo, following initial transplantation, that was able to support hematopoiesis upon serial transplantation. Our results show that a self-renewing cell population, capable of reconstituting the hematopoietic compartment, expanded ex vivo in the presence of Tat-MYC and Tat-Bcl-2 suggesting that this may be an attractive approach to expand human HSPCs ex vivo for clinical use.

  1. BET Inhibition Induces Apoptosis in Aggressive B-Cell Lymphoma via Epigenetic Regulation of BCL-2 Family Members.

    Science.gov (United States)

    Hogg, Simon J; Newbold, Andrea; Vervoort, Stephin J; Cluse, Leonie A; Martin, Benjamin P; Gregory, Gareth P; Lefebure, Marcus; Vidacs, Eva; Tothill, Richard W; Bradner, James E; Shortt, Jake; Johnstone, Ricky W

    2016-09-01

    Targeting BET bromodomain proteins using small molecules is an emerging anticancer strategy with clinical evaluation of at least six inhibitors now underway. Although MYC downregulation was initially proposed as a key mechanistic property of BET inhibitors, recent evidence suggests that additional antitumor activities are important. Using the Eμ-Myc model of B-cell lymphoma, we demonstrate that BET inhibition with JQ1 is a potent inducer of p53-independent apoptosis that occurs in the absence of effects on Myc gene expression. JQ1 skews the expression of proapoptotic (Bim) and antiapoptotic (BCL-2/BCL-xL) BCL-2 family members to directly engage the mitochondrial apoptotic pathway. Consistent with this, Bim knockout or Bcl-2 overexpression inhibited apoptosis induction by JQ1. We identified lymphomas that were either intrinsically resistant to JQ1-mediated death or acquired resistance following in vivo exposure. Strikingly, in both instances BCL-2 was strongly upregulated and was concomitant with activation of RAS pathways. Eμ-Myc lymphomas engineered to express activated Nras upregulated BCL-2 and acquired a JQ1 resistance phenotype. These studies provide important information on mechanisms of apoptosis induction and resistance to BET-inhibition, while providing further rationale for the translation of BET inhibitors in aggressive B-cell lymphomas. Mol Cancer Ther; 15(9); 2030-41. ©2016 AACR. PMID:27406984

  2. 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.

  3. The influence of sleep deprivation on expression of apoptosis regulatory proteins p53, bcl-2 and bax following rat tongue carcinogenesis induced by 4-nitroquinoline 1-oxide

    Directory of Open Access Journals (Sweden)

    Juliana Noguti

    2013-01-01

    Full Text Available Background: The aim of this study was to evaluate whether paradoxical sleep deprivation could affects the mechanisms and pathways essentials for cancer cells in tongue cancer induced by 4-nitroquinole 1-oxide in Wistar rats. Materials and Methods: For this purpose, the animals were distributed into 4 groups of 5 animals each treated with 50 ppm 4 nitroquinoline 1 oxide (4 NQO solution through their drinking water for 4 and 12 weeks. The animals were submitted to paradoxical sleep deprivation (PSD for 72 h using the modified multiple platform method, which consisted of placing 5 mice in a cage (41 × 34 × 16 cm containing 10 circular platforms (3.5 cm in diameter with water 1 cm below the upper surface. The investigations were conducted using immunohistochemistry of p53, Bax and Bcl-2 proteins related to apoptosis and its pathways. Statistical analysis was performed by Kruskal-Wallis non-parametric test followed by the Dunn′s test using SPSS software pack (version 1.0. P value < 0.05 was considered for statistic significance. Results: Although no histopathological abnormalities were induced in the epithelium after 4 weeks of carcinogen exposure in all groups, in 12 weeks were observed pre-neoplasic lesions. Data analysis revealed statistically significant differences ( P < 0.05 in 4 weeks group for p53 and for bcl-2 and for all immunomarkers after 12 weeks of 4NQO administration. Conclusion: Our results reveal that sleep deprivation exerted alterations in proteins associated with proliferation and apoptosis in carcinogenesis.

  4. Immunogenicity of Bcl-2 in patients with cancer

    DEFF Research Database (Denmark)

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

    2005-01-01

    -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...... 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...... and widely applicable target for anticancer immunotherapeutic strategies (eg, in the combination with conventional radiotherapy and chemotherapy)....

  5. 儿童成熟B-NHL中BCL-2、BCL-6蛋白表达及其临床病理意义%BCL-2 and BCL-6 protein expression in pediatric B-cell Non-Hodgkin′s lymphoma and its clinic-pathologic significance

    Institute of Scientific and Technical Information of China (English)

    王舒静; 俞懿; 高怡瑾; 孟建华; 陆凤娟; 李军; 王宏胜; 翟晓文; 苗慧; 钱晓文

    2014-01-01

    Objective The study was designed to investigate the protein expression of BCL-2 and BCL-6 in children with B-NHL and its clinic-pathological significance.Method Between July 1999 and October 2011,92 untreated patients (age 16 years or less)with newly diagnosed B-NHL (including BL, DLBCL and BL/DLBCL)were enrolled.We use the immunohistochemical technique (Envision TM)to detect BCL-2,BCL-6 protein expression levels.The expression of BCL-2 and BCL-6 and its association with clinic-pathological features and prognosis were analyzed.Results BCL-2 protein expression was performed in 47 B-NHL,the rate of positivity in BL and DLBCL were 9 .7% (3/3 1 ) and 33 .3%(5/15),respectively.There was significant difference between them (P=0.047).However,there was no association between the expression of BCL-2 and gender,stage and prognosis (P>0.05 ).BCL-6 protein expression was performed in 31 B-NHL,The 2-year EFS was 83.3% for children with BCL-6 protein expression,the other was 45.5%,there was significant difference between them (P=0.019). Children with positive BCL-6 protein expression had better prognosis.Conclusion BCL-2 protein expression was useful for distinguish BL from DLBCL and BCL-6 protein expression is a prognosis factor of B-NHL.%目的初步探讨儿童成熟B细胞非霍奇金淋巴瘤(B-NHL)中BCL-2、BCL-6蛋白表达及其临床病理意义。方法收集1999-2011年复旦大学附属儿科医院血液科收治的92例初治儿童B-NHL资料,包括伯基特淋巴瘤(burkitl lymphoma,BL)53例,弥漫大B细胞性淋巴瘤(DLBCL)38例,以及介于BL与DLBCL之间未能分类的B细胞淋巴瘤(BL/DLBCL)1例。92例患儿年龄≤16岁。所有病例均经过2家三级甲等医院病理科诊断。通过免疫组织化学技术检测儿童B-NHL中BCL-2、BCL-6蛋白表达情况。结果(1)92例儿童B-NHL中47例进行BCL-2蛋白检测,BCL-2表达阳性率在BL和DLBCL中分别为9.7%(3/31)和33.3%(5/15),差

  6. High-quality NMR structure of human anti-apoptotic protein domain Mcl-1(171-327 for cancer drug design.

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    Gaohua Liu

    Full Text Available A high-quality NMR solution structure is presented for protein hMcl-1(171-327 which comprises residues 171-327 of the human anti-apoptotic protein Mcl-1 (hMcl-1. Since this construct contains the three Bcl-2 homology (BH sequence motifs which participate in forming a binding site for inhibitors of hMcl-1, it is deemed to be crucial for structure-based design of novel anti-cancer drugs blocking the Mcl1 related anti-apoptotic pathway. While the coordinates of an NMR solution structure for a corresponding construct of the mouse homologue (mMcl-1 are publicly available, our structure is the first atomic resolution structure reported for the 'apo form' of the human protein. Comparison of the two structures reveals that hMcl-1(171-327 exhibits a somewhat wider ligand/inhibitor binding groove as well as a different charge distribution within the BH3 binding groove. These findings strongly suggest that the availability of the human structure is of critical importance to support future design of cancer drugs.

  7. Expression of protein encoded by apoptosis-associated gene p53, bcl-2, and bax in adaptive response of thymocyte apoptosis in mice induced by low dose radiation with X-rays

    International Nuclear Information System (INIS)

    Objective: To explore the regulative mechanism of apoptosis-associated gene proteins on the adaptive response of thymocyte apoptosis in mice induced by low dose radiation with X-rays. Methods: Kunming male mice were irradiated with the inductive doses (D1: 25, 50, 75, 100 and 200 mGy; dose rate: 12.5 mGy ·min-1) and the challenging dose (D2: 1.5 Gy; dose rate: 287 mGy·min-1). The time interval between D1 and D2 was 6 h. The expressive levels of thymocyte apoptosis-associated gene proteins were measured with flow cytometry. Results: As compared with the sham-irradiation, the positive percentage of thymocyte Bcl-2 protein expression decreased significantly in D2 group (P<0.05), Bax increased significantly (P<0.05), and Bcl-2/Bax decreased significantly (P<0.001); p 53 increased significantly (P<0.001). As compared with D2 group, the positive percentage of thymocyte Bcl-2 protein expression increased in varying degree in D1+ D2 group of 25-75 mGy D1, Bax decreased in varying degree, and Bcl-2/Bax increased significantly (P<0.01); p53 decreased significantly (P<0.001 or P<0.05). Conclusion: The apoptotic thymocytes in the adaptive response of thymocyte apoptosis in mice induced by irradiation with 25-75 mGy decrease significantly due to the increase of apoptosis-associated gene Bcl-2 protein expression and Bcl-2/Bax, the decrease of Bax and p53 protein expressions. (authors)

  8. The BCL2 rheostat in glucocorticoid-induced apoptosis of acute lymphoblastic leukemia

    Science.gov (United States)

    Ploner, C; Rainer, J; Niederegger, H; Eduardoff, M; Villunger, A; Geley, S; Kofler, R

    2016-01-01

    Glucocorticoid (GC)-induced apoptosis is essential in the treatment of acute lymphoblastic leukemia (ALL) and related malignancies. Pro- and anti-apoptotic members of the BCL2 family control many forms of apoptotic cell death, but the extent to which this survival ‘rheostat’ is involved in the beneficial effects of GC therapy is not understood. We performed systematic analyses of expression, GC regulation and function of BCL2 molecules in primary ALL lymphoblasts and a corresponding in vitro model. Affymetrix-based expression profiling revealed that the response included regulations of pro-apoptotic and, surprisingly, anti-apoptotic BCL2 family members, and varied among patients, but was dominated by induction of the BH3-only molecules BMF and BCL2L11/Bim and repression of PMAIP1/Noxa. Conditional lentiviral gene overexpression and knock-down by RNA interference in the CCRF-CEM model revealed that induction of Bim, and to a lesser extent that of BMF, was required and sufficient for apoptosis. Although anti-apoptotic BCL2 members were not regulated consistently by GC in the various systems, their overexpression delayed, whereas their knock-down accelerated, GC-induced cell death. Thus, the combined clinical and experimental data suggest that GCs induce both pro- and anti-apoptotic BCL2 family member-dependent pathways, with the outcome depending on cellular context and additional signals feeding into the BCL2 rheostat. PMID:18046449

  9. Ginsenoside Rh2 Mitigates Pediatric Leukemia Through Suppression of Bcl-2 in Leukemia Cells

    Directory of Open Access Journals (Sweden)

    Xiaoru Wang

    2015-09-01

    Full Text Available Background/Aims: Acute myeloid leukemia (AML is a severe malignant cancer worldwide, in both adult and pediatric patients. Since bone marrow cell transplantation is seriously limited by the availability of the immune-paired donor sources, the therapy for pediatric leukemia remains challenging. Ginsenoside Rh2 (GRh2 is a well-characterized component in red ginseng, and has established therapeutic effects for different diseases, although whether GRh2 may have a therapeutic effect on pediatric leukemia has not been investigated. Methods: We examined the effects of GRh2 on the survival of mice in an acute leukemia model. We analyzed the effects of GRh2 on the cell viability of leukemia cell lines in vitro, using a CCK-8 assay and an MTT assay. We analyzed the effects of GRh2 on the apoptosis of leukemia cell lines in vitro, by flow cytometry. We analyzed the levels of Bcl-2 and microRNA-21 (miR-21 in GRh2-treated leukemia cells. Prediction of binding between miR-21 and 3'-UTR of Bcl-2 mRNA was performed by a bioinformatics algorithm and confirmed by a dual luciferase reporter assay. Results: GRh2 significantly prolonged the survival of mice with pediatric leukemia. GRh2 significantly decreased the viability of leukemia cells in vitro, through induction of apoptosis. GRh2 significantly decreased the levels of an anti-apoptotic protein Bcl-2 in leukemia cells, possibly through induction of miR-21, which suppressed the translation of Bcl-2 mRNA via 3'-UTR binding. Conclusion: GRh2 may be an effective treatment for pediatric leukemia, and GRh2 may induce apoptosis of leukemia cells through miR-21-modulated suppression of Bcl-2.

  10. bax, but not bcl-2, influences the prognosis of human pancreatic cancer

    OpenAIRE

    Friess, H; Lu, Z; H. Graber; Zimmermann, A.; Adler, G.; Korc, M.; Schmid, R; Buchler, M

    1998-01-01

    Background—bcl-2 and bax belong to the bcl-2-related gene family, which marks a new class of genes that influence apoptosis. The bcl-2 oncogene acts as a broad antiapoptotic factor and extends both normal and tumour cell survival. In contrast, the bax gene is a promoter of apoptosis. 
Aims—To analyse the expression of bcl-2 and bax in pancreatic cancer and correlate the results with clinical parameters. 
Patients—Pancreatic cancer tissue samples were obtained fro...

  11. Selective Impairment of TH17-Differentiation and Protection against Autoimmune Arthritis after Overexpression of BCL2A1 in T Lymphocytes

    Science.gov (United States)

    Iglesias, Marcos; Augustin, Juan Jesús; Alvarez, Pilar; Santiuste, Inés; Postigo, Jorge; Merino, Jesús; Merino, Ramón

    2016-01-01

    The inhibition of apoptotic cell death in T cells through the dysregulated expression of BCL2 family members has been associated with the protection against the development of different autoimmune diseases. However, multiple mechanisms were proposed to be responsible for such protective effect. The purpose of this study was to explore the effect of the T-cell overexpression of BCL2A1, an anti-apoptotic BCL2 family member without an effect on cell cycle progression, in the development of collagen-induced arthritis. Our results demonstrated an attenuated development of arthritis in these transgenic mice. The protective effect was unrelated to the suppressive activity of regulatory T cells but it was associated with a defective activation of p38 mitogen-activated protein kinase in CD4+ cells after in vitro TCR stimulation. In addition, the in vitro and in vivo TH17 differentiation were impaired in BCL2A1 transgenic mice. Taken together, we demonstrated here a previously unknown role for BCL2A1 controlling the activation of CD4+ cells and their differentiation into pathogenic proinflammatory TH17 cells and identified BCL2A1 as a potential target in the control of autoimmune/inflammatory diseases. PMID:27433938

  12. Study the Relativity of Bcl-2 Protein Expression in Apoptosis of Intervertebral Disc Cells. in Different Ages of Human Body%Bcl-2蛋白表达与人类不同年龄段椎间盘组织细胞凋亡的相关性研究

    Institute of Scientific and Technical Information of China (English)

    刘晓冬; 刘际红; 王传生; 邢淑芳; 秦博文; 王志彬

    2011-01-01

    目的:探讨凋亡相关蛋白Bcl-2在人类不同年龄段椎间盘组织细胞凋亡的作用.方法:采用脱氧核糖核苷酸末端转移酶介导的缺口末端标记法(terminal deoxynucleotidyl transferase mediated dUTP nick end labeling,TUNEL)、免疫组织化学方法以及HE染色法对人类不同年龄段正常人腰椎间盘髓核细胞对比.结果:①HE染色:在胚胎和儿童时期髓核内以脊索细胞为主,到成年后以软骨样细胞为主.从胚胎后期开始,椎间盘髓核细胞数量随年龄增长而逐渐减少,到老年阶段髓核细胞的数量已经很少(P<0.05).②TUNEL检测:胚胎后期即可见髓核细胞TUNEL反应阳性,而且在各年龄段均可见TUNEL反应阳性细胞,阳性颗粒的平均光密度值逐年增高(P<0.05).从胚胎后期到成年,TUNEL阳性细胞率随年龄增长而逐渐降低,并降到整个生命过程中的最低点;继之,TUNEL阳性细胞率又逐年升高(P<0.05).③Bcl-2蛋白免疫组织化学染色:自胚胎后期开始,Bcl-2蛋白就开始有较高水平的表达,但呈现逐年下降的趋势(P<0.05).Bcl-2蛋白阳性细胞表达率亦呈同样趋势(P<0.05).结论:在整个生命过程中,随年龄增长大量腰椎间盘髓核细胞发生凋亡,细胞数量明显减少.细胞凋亡是椎间盘细胞减少的原因之一.Bcl-2蛋白可能参与了椎间盘细胞凋亡的调节,但表达水平较低,不能阻止细胞凋亡的发生.%Objective: To explore the expression of Bcl-2 protein in apoptosis of intervertebral disc cells and gene regulation in different ages of human body. Method: The apoptotie status and the expression of Bcl-2 protein in the intervertebral disc ceils in different ages of human body were detected with TdT-mediated dUTP-biotin nick end labeling (TUNEL) and immunohistochemistry methods. Result: ①Hematoxylin and eosin staining: In embryonal and infantile stages, notochordal cells are the mainly kind of cells in different ages of human intervertebral disc

  13. Cellular responses to a prolonged delay in mitosis are determined by a DNA damage response controlled by Bcl-2 family proteins.

    Science.gov (United States)

    Colin, Didier J; Hain, Karolina O; Allan, Lindsey A; Clarke, Paul R

    2015-03-01

    Anti-cancer drugs that disrupt mitosis inhibit cell proliferation and induce apoptosis, although the mechanisms of these responses are poorly understood. Here, we characterize a mitotic stress response that determines cell fate in response to microtubule poisons. We show that mitotic arrest induced by these drugs produces a temporally controlled DNA damage response (DDR) characterized by the caspase-dependent formation of γH2AX foci in non-apoptotic cells. Following exit from a delayed mitosis, this initial response results in activation of DDR protein kinases, phosphorylation of the tumour suppressor p53 and a delay in subsequent cell cycle progression. We show that this response is controlled by Mcl-1, a regulator of caspase activation that becomes degraded during mitotic arrest. Chemical inhibition of Mcl-1 and the related proteins Bcl-2 and Bcl-xL by a BH3 mimetic enhances the mitotic DDR, promotes p53 activation and inhibits subsequent cell cycle progression. We also show that inhibitors of DDR protein kinases as well as BH3 mimetics promote apoptosis synergistically with taxol (paclitaxel) in a variety of cancer cell lines. Our work demonstrates the role of mitotic DNA damage responses in determining cell fate in response to microtubule poisons and BH3 mimetics, providing a rationale for anti-cancer combination chemotherapies.

  14. Bcl-2 gene therapy for apoptosis following traumatic brain injury

    Institute of Scientific and Technical Information of China (English)

    YANG Xiao-feng; ZHENG Xue-sheng; LIU Wei-guo; FENG Jun-feng

    2006-01-01

    Objective: To investigate the therapeutic effect of Bcl- 2 fusion protein on apoptosis in brain following traumatic brain injury.Methods: Bcl-2 gene was cloned by RT-PCR. Bcl-2 and EGFP genes were linked together and inserted into pAdeno-X vector. This recombinant vector was packaged into infectious adenovirus in HEK293 cells. Ninety Wistar rats were assigned randomly into experimental group(n=45) and control group (n=45). All rats were subjected to traumatic brain injury. Then recombinant adenovirus (for experimental group) or saline (for control group) was injected into the traumatic brain. The expression of Bcl-2 fusion protein was investigated by Western blotting, immunohistochemistry and fluorescence microscopy. Apoptosis in the injured brain was studied by TUNEL. Animals' behavior capacity was evaluated by tiltboard test.Results: In the experimental group, many fluorescent cells were found around the traumatic locus,which were also proven to be Bcl-2-positive by immunohistochemistry. On the contrary, few Bcl-2-positive cells and no fluorescent cell were detected in the control group. Bcl-2 expression of experimental group was much higher than that of control group, which was illustrated by Western blotting. The apoptosis index of experimental group was 0.027 ± 0.005, and that of control group was 0.141±0.025 (P<0.01). Two weeks after injury, animals of the experimental group behaved better than those of the control group.Conclusions: A recombinant adenovirus vector expressing Bcl-2 fusion protein has been constructed. Bcl-2 fusion protein can suppress apoptosis and promote cell survival. Moreover, the behavior recovery of the injured animal is promoted. Bcl-2 fusion protein provides a way to track the target cells in vivo.

  15. Crizotinib (PF-2341066) induces apoptosis due to downregulation of pSTAT3 and BCL-2 family proteins in NPM-ALK(+) anaplastic large cell lymphoma.

    Science.gov (United States)

    Hamedani, Farid Saei; Cinar, Munevver; Mo, Zhicheng; Cervania, Melissa A; Amin, Hesham M; Alkan, Serhan

    2014-04-01

    Nucleophosmin-anaplastic lymphoma kinase (NPM-ALK) is an aberrant fusion gene product with tyrosine kinase activity and is expressed in substantial subset of anaplastic large cell lymphomas (ALCL). It has been shown that NPM-ALK binds to and activates signal transducer and activator of transcription 3 (STAT3). Although NPM-ALK(+) ALCL overall shows a better prognosis, there is a sub-group of patients who relapses and is resistant to conventional chemotherapeutic regimens. NPM-ALK is a potential target for small molecule kinase inhibitors. Crizotinib (PF-2341066) is a small, orally bioavailable molecule that inhibits growth of tumors with ALK activity as shown in a subgroup of non-small lung cancer patients with EML4-ALK expression. In this study, we have investigated the in vitro effects of Crizotinib in ALCL cell line with NPM-ALK fusion. Crizotinib induced marked downregulation of STAT3 phosphorylation, which was associated with significant apoptotic cell death. Apoptosis induction was attributed to caspase-3 cleavage and marked downregulation of the Bcl-2 family of proteins including MCL-1. These findings implicate that Crizotinib has excellent potential to treat patients with NPM-ALK(+) ALCL through induction of apoptotic cell death and downregulation of major oncogenic proteins in this aggressive lymphoma.

  16. Niclosamide, an anti-helminthic molecule, downregulates the retroviral oncoprotein Tax and pro-survival Bcl-2 proteins in HTLV-1-transformed T lymphocytes

    Energy Technology Data Exchange (ETDEWEB)

    Xiang, Di [Penn State Hershey Cancer Institute, Penn State University College of Medicine, Hershey, PA 17033 (United States); Yuan, Yunsheng [Penn State Hershey Cancer Institute, Penn State University College of Medicine, Hershey, PA 17033 (United States); Engineering Research Center of Cell and Therapeutic Antibody, Ministry of Education, School of Pharmacy, Shanghai Jiao Tong University, Shanghai (China); Chen, Li [Pharmacy College, Fujian University of Traditional Chinese Medicine, Fuzhou (China); Institute of Human Virology, University of Maryland School of Medicine, Baltimore, MD 21201 (United States); Liu, Xin; Belani, Chandra [Penn State Hershey Cancer Institute, Penn State University College of Medicine, Hershey, PA 17033 (United States); Cheng, Hua, E-mail: hcheng@ihv.umaryland.edu [Institute of Human Virology, University of Maryland School of Medicine, Baltimore, MD 21201 (United States); Marlene and Stewart Greenebaum Cancer Center, University of Maryland School of Medicine, Baltimore, MD 21201 (United States); Department of Medicine, University of Maryland School of Medicine, Baltimore, MD 21201 (United States); Department Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, MD 21201 (United States)

    2015-08-14

    Adult T cell leukemia and lymphoma (ATL) is a highly aggressive form of hematological malignancy and is caused by chronic infection of human T cell leukemia virus type 1 (HTLV-1). The viral genome encodes an oncogenic protein, Tax, which plays a key role in transactivating viral gene transcription and in deregulating cellular oncogenic signaling to promote survival, proliferation and transformation of virally infected T cells. Hence, Tax is a desirable therapeutic target, particularly at early stage of HTLV-1-mediated oncogenesis. We here show that niclosamide, an anti-helminthic molecule, induced apoptosis of HTLV-1-transformed T cells. Niclosamide facilitated degradation of the Tax protein in proteasome. Consistent with niclosamide-mediated Tax degradation, this compound inhibited activities of MAPK/ERK1/2 and IκB kinases. In addition, niclosamide downregulated Stat3 and pro-survival Bcl-2 family members such as Mcl-1 and repressed the viral gene transcription of HTLV-1 through induction of Tax degradation. Since Tax, Stat3 and Mcl-1 are crucial molecules for promoting survival and growth of HTLV-1-transformed T cells, our findings demonstrate a novel mechanism of niclosamide in inducing Tax degradation and downregulating various cellular pro-survival molecules, thereby promoting apoptosis of HTLV-1-associated leukemia cells. - Highlights: • Niclosamide is a promising therapeutic candidate for adult T cell leukemia. • Niclosamide employs a novel mechanism through proteasomal degradation of Tax. • Niclosamide downregulates certain cellular pro-survival molecules.

  17. Effect of Acupuncture plus Astragalus Polysaccharide on the Expression of Bcl-2 Protein in Islet  Cells in db/db Mice%针刺联合黄芪多糖对db/db小鼠胰岛β细胞Bcl-2蛋白表达的影响

    Institute of Scientific and Technical Information of China (English)

    张文奎; 李茜; 宫翠红; 孙志

    2016-01-01

    Objective To investigate the effect of acupuncture plus astragalus polysaccharide on the expression of Bcl-2 protein in pancreatic islet b cells in db/db mice. Method C57BL/Ksj-db/db mice as an animal model of spontaneous type 2 diabetes were selected for this experiment. Five-week-old db/db mice were randomized into model, acupuncture, medication and acupuncture+medication groups. Meanwhile, db/m mice were selected as a normal group. The acupuncture group received acupuncture at points Housanli (equivalent to Zusanli, ST36), Neiting(ST44) and Yishu(Extra) and the medication group, an oral gavage of astragalus polysaccharide (1400 mg/kg). Both groups were treated once daily, for 12 consecutive weeks. After the end of experiment, blood glucose, insulin and resistin were measured, and the expression of Bcl-2 protein in islet b cells was determined by immunohistochemical method. Result Blood glucose, insulin and resistin levels were significantly lower in the acupuncture+medication, acupuncture and medication groups than in the model group. They were significantly lower in the acupuncture+medication group than in the acupuncture and medication groups and significantly lower in the acupuncture group than in the medication group. The expression of Bcl-2 protein in islet b cells was higher in the medication, acupuncture and acupuncture+medication groups than in the model group; there was a statistically significant difference (P0.05). Conclusion Acupuncture plus astragalus polysaccharide can significantly reduce blood glucose and serum insulin and resistin levels and increase the expression of Bcl-2 protein in islet b cells to effectively inhibit apoptosis in islet b cells in db/db mice. Its effect is better than that of acupuncture alone or medication.%目的:观察针刺联合黄芪多糖对 db/db 小鼠胰岛b细胞 Bcl-2蛋白表达的影响。方法选用自发性2型糖尿病动物模型C57BL/Ksj-db/db 小鼠为本实验动物模型。将5周龄db/db 小鼠随

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

    International Nuclear Information System (INIS)

    Highlights: ► Ro52low 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 Ro52low HeLa cells were significantly more resistant to apoptosis than wild-type HeLa cells when stimulated by H2O2- 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.

  19. 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.

  20. Enhanced apoptotic response to photodynamic therapy after bcl-2 transfection.

    Science.gov (United States)

    Kim, H R; Luo, Y; Li, G; Kessel, D

    1999-07-15

    Apoptosis is a cellular death process involving the sequential activation of a series of caspases, endonucleases, and other enzymes. The initiation of apoptosis can be inhibited by overexpression of bcl-2 and certain other members of a related family of proteins. We examined the effects of bcl-2 overexpression on the apoptotic response to photodynamic therapy (PDT), using aluminum phthalocyanine as the photosensitizing agent. In this study, we compared the immortalized human breast epithelial cell line MCF10A with a subline (MCF10A/bcl-2) transfected with the human bcl-2 gene. The latter was approximately 2-fold more sensitive to the phototoxic effects of PDT. At a 50 mJ/cm2 light dose, photodamage to MCF-10A/bcl-2 resulted in a greater loss of the mitochondrial membrane potential (delta(psi)m), enhanced release of mitochondrial cytochrome c, a more rapid and greater activation of caspase-3, and a greater apoptotic response. Western blot analysis revealed that the transfected cell line showed overexpression of both bcl-2 and bax, and that PDT caused selective destruction of bcl-2, leaving bax unaffected. The greater apoptotic response by the transfected line is, therefore, attributed to the higher bax:bcl-2 ratio after photodamage.

  1. Identification of the Bcl-2 family protein gene BOK from orange-spotted grouper (Epinephelus coioides) involved in SGIV infection.

    Science.gov (United States)

    Cai, Jia; Yu, Dapeng; Wei, Shina; Tang, Jufen; Lu, Yishan; Wu, Zaohe; Qin, Qiwei; Jian, Jichang

    2016-05-01

    Apoptosis plays vital roles in many physiological process and immune response. BOK is one of the central regulators in apoptosis. In this study, a new BOK homolog (Ec-BOK) was cloned and characterized from Orange-spotted grouper, Epinephelus coioides. Ec-BOK encoded a 210 amino acid peptides which shared 97% identity to Stegastes partitus BOK protein, contained four BH domains and one transmembrane region. Ec-BOK widely expressed in all analyzed tissues with the higher expressions in kidney and spleen. Its expression level was up-regulated after SGIV infection in vitro. Further analysis revealed that overexpression of Ec-BOK inhibited viral genes transcriptions and virus replication in fish cell. Our findings suggested that Ec-BOK might play a role in the immune response against virus.

  2. Minocycline mechanism of neuroprotection involves the Bcl-2 gene family in optic nerve transection.

    Science.gov (United States)

    Levkovitch-Verbin, Hani; Waserzoog, Yael; Vander, Shelly; Makarovsky, Daria; Ilia, Piven

    2014-10-01

    The second-generation tetracycline, minocycline, has been shown to exhibit neuroprotective therapeutic benefits in many neurodegenerative diseases including experimental glaucoma and optic nerve transection (ONT). This study investigated the mechanism underlying minocycline neuroprotection in a model of ONT. ONT was applied unilaterally in 36 Wistar rat eyes. The rats were randomly divided into a minocycline (22 mg/kg/d) treatment group and a saline treatment group (control). Treatment (minocycline or saline) was given by intraperitoneal injections initiated 3 d before ONT and continued daily until the end of the experiment. The involvement of pro-apoptotic, pro-survival and inflammatory pathways was analyzed by quantitative Real-Time Polymerase Chain Reaction at 4 h and 3 d after the transection in both treatment groups. The involvement of Bcl-2 protein was evaluated by immunohistochemistry. We found that Minocycline significantly increased the expression of the antiapoptotic gene bcl-2 4 h after transection (n = 8, p = 0.008) and decreased the expression of Bax at the same time point (n = 8, p = 0.03). Tumor Necrosis Factor α (TNFα), Inhibitor of Apoptosis Protein (IAP1) and Gadd45α were significantly upregulated in the retinas of eyes with ONTs compared to control (n = 10 for each gene, p = 0.02, p = 0.03, p = 0.04, respectively) but this effect was unaffected by minocycline. This study further support that the mechanism underlying minocycline neuroprotection involves the Bcl-2 gene family, suggesting that minocycline has antiapoptotic properties that support its value as a promising neuroprotective drug. PMID:24410139

  3. Overexpression of the hydatidiform mole-related gene F10 inhibits apoptosis in A549 cells through downregulation of BCL2-associated X protein and caspase-3.

    Science.gov (United States)

    Song, Yali; Zhang, Gong; Zhu, Xiulan; Pang, Zhanjun; Xing, Fuqi; Quan, Song

    2012-09-01

    The aim of this study was to investigate how the overexpression of the hydatidiform mole-related gene F10 affects apoptosis in human lung cancer A549 cells. A549 cells were transfected with pEGFP-N1-F10 (A549-F10) or pEGFP-N1 empty vector (A549-empty). Untransfected A549, A549-F10 or A549-empty cells were examined using the MTT cell proliferation assay and the TUNEL-FITC/Hoechst 33258 apoptosis assay. Western blotting was used to examine the expression levels of the pro-apoptotic genes, BCL2-associated X protein (BAX) and caspase-3. F10 was stably expressed in A549 cells. From 12 h, A549-F10 cells proliferated markedly faster than the untransfected and A549-empty cells. F10 overexpression also significantly inhibited apoptosis, as shown by the reduced number of TUNEL and Hoechst 33258 double-positive cells. This inhibition was likely due to an F10-induced reduction in the BAX and caspase-3 levels. The results of this study indicate that F10 overexpression inhibits apoptosis in A549 cells through the downregulation of the pro-apoptotic genes BAX and caspase-3. PMID:23741243

  4. Epstein-Barr virus interactions with the Bcl-2 protein family and apoptosis in human tumor cells

    Institute of Scientific and Technical Information of China (English)

    Qin FU; Chen HE; Zheng-rong MAO

    2013-01-01

    Epstein-Barr virus (EBV),a human gammaherpesvirus carried by more than 90% of the world's population,is associated with malignant tumors such as Burkitt's lymphoma (BL),Hodgkin lymphoma,post-transplant lymphoma,extra-nodal natural killer/T cell lymphoma,and nasopharyngeal and gastric carcinomas in immune-compromised patients.In the process of infection,EBV faces challenges:the host cell environment is harsh,and the survival and apoptosis of host cells are precisely regulated.Only when host cells receive sufficient survival signals may they immortalize.To establish efficiently a lytic or long-term latent infection,EBV must escape the host cell immunologic mechanism and resist host cell apoptosis by interfering with multiple signaling pathways.This review details the apoptotic pathway disrupted by EBV in EBV-infected cells and describes the interactions of EBV gene products with host cellular factors as well as the function of these factors,which decide the fate of the host cell.The relationships between other EBV-encoded genes and proteins of the B-cell leukemia/lymphoma (Bcl) family are unknown.Still,EBV seems to contribute to establishing its own latency and the formation of tumors by modifying events that impact cell survival and proliferation as well as the immune response of the infected host.We discuss potential therapeutic drugs to provide a foundation for further studies of tumor pathogenesis aimed at exploiting novel therapeutic strategies for EBV-associated diseases.

  5. Effect of Shenfu parenteral injection on the expressions of Bcl-2, Bax and c-Fos proteins in ischemia reperfusion myocardium of rats%参附注射液影响大鼠缺血再灌注心肌Bcl-2,Bax与c-Fos蛋白的表达

    Institute of Scientific and Technical Information of China (English)

    陈玉培; 牟崇明; 季道如; 但伶; 龚文婷; 王莉莎

    2006-01-01

    -2/Bax比率显著升高(P<0.01).结论:参附注射液对缺血再灌注心肌保护效应可能与其促进Bcl-2蛋白高表达、抑制Bax与c-Fos蛋白表达、增加Bcl-2/Bax比率,从而抑制心肌细胞凋亡有关.%BACKGROUND: It has been confirmed that Shenfu parenteral injection can ameliorate and treat various shocks, heart failure, myocardial ischemia and supraventricular/ventricular arrhythmia, and it also has a good protective effect on myocardial ischemia/reperfusion injury in rats.OBJECTIVE: To observe the effects of Shenfu parenteral injection on the protein expressions of myocardial apoptosis-related genes of Bcl-2, Bax and c-Fos in rats with acute ischemia/reperfusion injury.DESIGN: A complete randomized grouping design, controlled experiment.SETTING: Department of Anesthesiology, the Second Affiliated Hospital,Chongqing University of Medical Sciences.MATERIALS: The experiments were carried out in the Staff Room of Anesthesiology, the Second Affiliated Hospital, Chongqing University of Medical Sciences from April to December in 2004. Thirty-five healthy adult Wistar rats were provided by the experimental animaI center of Daping Hospital, Third Military Medical University of Chinese PLA. Shenfu parenteral injection was the TCM formula of Shenfu Tang, which is for recuperating depleted yang and rescuing the patient from collapse, and its main components are ginsenoside and aconitum alkaloid. It was the product of Yaan Sanjiu Pharmaceutical Co., Ltd., 10 mL/piece, the batch number was 030110.METHODS: In vivo models of myocardial ischemia/reperfusion injury were used. The 35 rats were divided into 5 groups according to the number of random number table, with 7 rats in each group: ① Sham-operated group: The rats were treated with only insertion of thread without ligation, followed by intravenous injection of saline (8 mL/kg), and then observed for 120 minutes. ② Shenfu parenteral injection 30-minute group: The rats were treated with intravenous

  6. Bim/Bcl-2 balance is critical for maintaining naive and memory T cell homeostasis

    Science.gov (United States)

    Wojciechowski, Sara; Tripathi, Pulak; Bourdeau, Tristan; Acero, Luis; Grimes, H. Leighton; Katz, Jonathan D.; Finkelman, Fred D.; Hildeman, David A.

    2007-01-01

    We examined the role of the antiapoptotic molecule Bcl-2 in combating the proapoptotic molecule Bim in control of naive and memory T cell homeostasis using Bcl-2−/− mice that were additionally deficient in one or both alleles of Bim. Naive T cells were significantly decreased in Bim+/−Bcl-2−/− mice, but were largely restored in Bim−/−Bcl-2−/− mice. Similarly, a synthetic Bcl-2 inhibitor killed wild-type, but not Bim−/−, T cells. Further, T cells from Bim+/−Bcl-2−/− mice died rapidly ex vivo and were refractory to cytokine-driven survival in vitro. In vivo, naive CD8+ T cells required Bcl-2 to combat Bim to maintain peripheral survival, whereas naive CD4+ T cells did not. In contrast, Bim+/−Bcl-2−/− mice generated relatively normal numbers of memory T cells after lymphocytic choriomeningitis virus infection. Accumulation of memory T cells in Bim+/−Bcl-2−/− mice was likely caused by their increased proliferative renewal because of the lymphopenic environment of the mice. Collectively, these data demonstrate a critical role for a balance between Bim and Bcl-2 in controlling homeostasis of naive and memory T cells. PMID:17591857

  7. Bcl-2/caspase 3 mucosal imbalance favors T cell resistance to apoptosis in dogs with inflammatory bowel disease.

    Science.gov (United States)

    Jergens, A; Young, J; Moore, D; Wang, C; Hostetter, J; Augustine, L; Allenspach, K; Schmitz, S; Mosher, C

    2014-04-15

    Canine idiopathic inflammatory bowel disease (IBD) is believed to result from complex interplay between genetic, microbial, and immunologic factors. Abnormal cell death by apoptosis may result in the persistence of activated intestinal T cells that contribute to mucosal inflammation and clinical severity. To test this hypothesis, we investigated the mucosal expression of pro- and anti-apoptotic proteins in different intestinal compartments and their association with inflammatory indices in dogs with IBD. Apoptosis of lamina propria (LP) T cells in duodenal, ileal, and colonic tissues in control and IBD dogs was analyzed by caspase 3/Bcl-2 immunohistochemistry and TUNEL assays. Densities and distributions of LP caspase 3 and Bcl-2 cells were correlated to histopathologic lesions and the clinical activity index (CIBDAI). Compared to control tissues, IBD dogs had significantly (Pdogs, there were significantly greater numbers of Bcl-2 cells at the apical and basilar villus in the duodenum as compared to the colon and to the apical and basilar villus in the ileum (Pdogs compared with controls (Pdogs and the CIBDAI (Pdogs with IBD. Mucosal imbalance of Bcl-2/caspase 3 expression favors T cell resistance to apoptosis which may contribute to T cell accumulation and chronic intestinal inflammation, similar to human IBD.

  8. Design of Bcl-2 and Bcl-xL Inhibitors with Subnanomolar Binding Affinities Based upon a New Scaffold

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Haibin; Chen, Jianfang; Meagher, Jennifer L.; Yang, Chao-Yie; Aguilar, Angelo; Liu, Liu; Bai, Longchuan; Cong, Xin; Cai, Qian; Fang, Xueliang; Stuckey, Jeanne A.; Wang, Shaomeng (Michigan)

    2014-10-02

    Employing a structure-based strategy, we have designed a new class of potent small-molecule inhibitors of the anti-apoptotic proteins Bcl-2 and Bcl-xL. An initial lead compound with a new scaffold was designed based upon the crystal structure of Bcl-xL and U.S. Food and Drug Administration (FDA) approved drugs and was found to have an affinity of 100 {micro}M for both Bcl-2 and Bcl-xL. Linking this weak lead to another weak-affinity fragment derived from Abbott's ABT-737 led to an improvement of the binding affinity by a factor of >10,000. Further optimization ultimately yielded compounds with subnanomolar binding affinities for both Bcl-2 and Bcl-xL and potent cellular activity. The best compound (21) binds to Bcl-xL and Bcl-2 with K{sub i} < 1 nM, inhibits cell growth in the H146 and H1417 small-cell lung cancer cell lines with IC{sub 50} values of 60-90 nM, and induces robust cell death in the H146 cancer cell line at 30-100 nM.

  9. Hypercapnia Inhibits Autophagy and Bacterial Killing in Human Macrophages by Increasing Expression of Bcl-2 and Bcl-xL

    Science.gov (United States)

    Casalino-Matsuda, S. Marina; Nair, Aisha; Beitel, Greg J.; Gates, Khalilah L.; Sporn, Peter H. S.

    2015-01-01

    Hypercapnia, the elevation of CO2 in blood and tissue, commonly develops in patients with advanced lung disease and severe pulmonary infections, and is associated with high mortality. We previously reported that hypercapnia alters expression of host defense genes, inhibits phagocytosis, and increases the mortality of Pseudomonas pneumonia in mice. However, the effect of hypercapnia on autophagy, a conserved process by which cells sequester and degrade proteins and damaged organelles that also plays a key role in antimicrobial host defense and pathogen clearance, has not previously been examined. In the present study we show that hypercapnia inhibits autophagy induced by starvation, rapamycin, LPS, heat-killed and live bacteria in the human macrophage. Inhibition of autophagy by elevated CO2 was not attributable to acidosis. Hypercapnia also reduced macrophage killing of Pseudomonas aeruginosa. Moreover, elevated CO2 induced the expression of Bcl-2 and Bcl-xL, anti-apoptotic factors that negatively regulate autophagy by blocking Beclin 1, an essential component of the autophagy initiation complex. Furthermore, siRNA targeting Bcl-2 and Bcl-xL and the small molecule Z36, which blocks Bcl-2 and Bcl-xL binding to Beclin 1, prevented hypercapnic inhibition of autophagy and bacterial killing. These results suggest that targeting the Bcl-2/Bcl-xL-Beclin 1 interaction may hold promise for ameliorating hypercapnia-induced immunosuppression and improving resistance to infection in patients with advanced lung disease and hypercapnia. PMID:25895534

  10. Effects of intermittent hypoxic preconditioning on apoptosis-related Bcl-2 and Bax protein expression in rat liver after partial hepatectomy under ischemia-reperfusion%间断低氧预适应对大鼠肝切除缺血再灌注肝脏凋亡相关蛋白Bcl-2、Bax表达的影响

    Institute of Scientific and Technical Information of China (English)

    王健; 李鹏飞; 韩效帆; 朱世春; 李广; 李俊; 张培建

    2014-01-01

    目的 观察术前间断低氧预适应对大鼠70%肝切术后缺血再灌注损伤肝脏凋亡相关蛋白Bcl-2和Bax表达的影响.方法 健康清洁级SD大鼠54只,用SPSS软件随机分为3组,每组18只:(1)肝切除组(PH组),切除肝脏的左叶和中叶(约占总肝重的70%);(2)缺血再灌注组(IR组),即在肝门阻断下切除肝脏的左叶和中叶,肝门阻断20 min后开放血流,残余肝脏发生了缺血再灌注过程;(3)间断低氧预适应组(IHP组),术前1周将大鼠置于氧气体积分数为10%的低氧环境中,每天1h.1周后在肝门阻断下行肝切除术(同IR组).各组分别于术后12、24、48 h进行取材检测,用全自动生化分析仪检测血清谷丙转氨酶(ALT)、谷草转氨酶(AST)含量,采用免疫组化方法检测残余肝组织Bcl-2、Bax表达情况.结果 在术后各时间点,IR组和IHP组血清ALT和AST水平均显著高于PH组,但IHP组明显低于IR组.与IR组相比,IHP组术后各时间点肝脏Bcl-2蛋白表达显著升高,而Bax蛋白表达显著下降.差异均有统计学意义(P<0.05).结论 间断低氧预适应对残余肝脏缺血再灌注损伤具有保护作用,其途径可能是通过促进抗凋亡蛋白Bcl-2表达和抑制促凋亡蛋白Bax表达,来减少肝细胞凋亡.%Objective To observe the effects of intermittent hypoxic preconditioning on the expression of apoptosis-related Bcl-2 and Bax protein after 70% hepatectomy combined with ischemia-reperfusion injury.Methods A total of fifty-four SD rats were randomly divided into three groups (n =18).Partial hepatectomy hroup (PH Group):Rats underwent the left and middle lobectomy of liver(70% hepatectomy).Ischemia reperfusion group (IR group):The left and middle lobes of liver were resected during the occlusion of the hepatoduodenal ligament for 20 minutes.Residual liver underwent the process of ischemia-reperfusion.Intermittent hypoxia preconditioning group (IHP group):rats were exposed to hypoxic environment of 10

  11. Bcl-2/adenovirus E1B 19 kDa interacting protein-3 knockdown enables growth of breast cancer metastases in the lung, liver, and bone.

    Science.gov (United States)

    Manka, David; Spicer, Zachary; Millhorn, David E

    2005-12-15

    The mouse breast cancer cell lines 4T1, 4T07, and 67NR are highly tumorigenic but vary in metastatic potential: 4T1 widely disseminates, resulting in secondary tumors in the lung, liver, bone, and brain; 4T07 spreads to the lung and liver but is unable to establish metastatic nodules; 67NR is unable to metastasize. The Bcl-2/adenovirus E1B 19 kDa interacting protein-3 (Bnip-3) was recently shown to be absent after hypoxia in pancreatic cancer cell lines whereas its overexpression restored hypoxia-induced cell death. We found that Bnip-3 expression increased after 6 hours of hypoxia in all cell lines tested but was highest in the nonmetastatic 67NR cells and lowest in the highly metastatic 4T1 cells. Hypoxia-induced expression of Bnip-3 in the disseminating but nonmetastatic 4T07 cells was intermediate compared with 4T1 and 67NR cells. Cleaved caspase-3, a key downstream effector of cell death, increased after 6 hours of hypoxia in the 67NR and 4T07 cells by 1.9- and 2.5-fold, respectively. Conversely, cleaved caspase-3 decreased by 45% in the highly metastatic 4T1 cells after hypoxia. Small interfering RNA oligonucleotides targeting endogenous Bnip-3 blocked cell death and increased clonigenic survival after hypoxic challenge in vitro and increased primary tumor size and enabled metastasis to the lung, liver, and sternum of mice inoculated with 4T07 cells in vivo. These data inversely correlate the hypoxia-induced expression of the cell death protein Bnip-3 to metastatic potential and suggest that loss of Bnip-3 expression is critical for malignant and metastatic evasion of hypoxia-induced cell death. PMID:16357180

  12. EXPRESSION AND SIGNIFICANCE OF bcl-2 FAMILY IN AMELOBLASTONA

    Institute of Scientific and Technical Information of China (English)

    WANG Jie; MA Jie; ZHONG Ming; LIU Jing-dong

    2006-01-01

    Objective: To study the expression of bcl-2 and bax in human ameloblastoma (AB), and investigate the role of apoptosis in genesis and development of AB and the relation of apoptosis with the clinic biological characteristics of AB. Methods:BCL-2 and BAX proteins were detected in 75 cases of AB (primary AB 31 cases, recurrent AB 37 cases, malignant AB 7cases) by S-P method. Oral normal mucosa (NOM) and Odontogenic kerotosyst (OKC) were used as controls. Bcl-2 and bax mRNA in 20 cases of AB, 12 cases of OKC were detected by in situ hybridization. Results: The positive ratio of BCL-2protein was 88.0% ( 66/75 ) in AB, 74.3% (26/35) in OKC and 44.4% (4/9) in NOM, respectively (P<0.001). BCL-2 protein was expressed in peripheral cells and a few scattered stellate-shape cells in AB. The positive ratio of BAX protein was 74.7%(56/75)in AB, 65.7%(23/35)in OKC and 77.8%(7/9) in NOM, respectively (P<0.001). BAX protein was expressed in peripheral cells and stellate-shape cells with similar intensity. BCL-2 expression increased in recurrent and AB canceration(P<0.01), while for BAX expression, the positive ratio was higher in recurrent AB, but lower than that of malignant AB. A moderate negative correlation between BCL-2 and BAX protein was found (rk=-0.331, P<0.001).Conclusion: AB has much more apoptosis-inhibiting protein than apoptosis- accelarating protein. Apoptosis plays an important role in genesis, development of AB. The fashion and intensity of bcl-2 and bax expression were different in various tissues and in benign or malignant AB.

  13. CHIP buffers heterogeneous Bcl-2 expression levels to prevent augmentation of anticancer drug-resistant cell population.

    Science.gov (United States)

    Tsuchiya, M; Nakajima, Y; Waku, T; Hiyoshi, H; Morishita, T; Furumai, R; Hayashi, Y; Kishimoto, H; Kimura, K; Yanagisawa, J

    2015-08-27

    Many types of cancer display heterogeneity in various features, including gene expression and malignant potential. This heterogeneity is associated with drug resistance and cancer progression. Recent studies have shown that the expression of a major protein quality control ubiquitin ligase, carboxyl terminus of Hsc70-interacting protein (CHIP), is negatively correlated with breast cancer clinicopathological stages and poor overall survival. Here we show that CHIP acts as a capacitor of heterogeneous Bcl-2 expression levels and prevents an increase in the anticancer drug-resistant population in breast cancer cells. CHIP knockdown in breast cancer cells increased variation in Bcl-2 expression levels, an antiapoptotic protein, among the cells. Our results also showed that CHIP knockdown increased the proportion of anticancer drug-resistant cells. These findings suggest that CHIP buffers variation in gene expression levels, affecting resistance to anticancer drugs. In single-cell clones derived from breast cancer cell lines, CHIP knockdown did not alter the variation in Bcl-2 expression levels and the proportion of anticancer drug-resistant cells. In contrast, when clonal cells were treated with a mutagen, the variation in Bcl-2 expression levels and proportion of anticancer drug-resistant cells were altered by CHIP knockdown. These results suggest that CHIP masks genetic variations to suppress heterogeneous Bcl-2 expression levels and prevents augmentation of the anticancer drug-resistant population of breast cancer cells. Because genetic variation is a major driver of heterogeneity, our results suggest that the degree of heterogeneity in expression levels is decided by a balance between genetic variation and the buffering capacity of CHIP.

  14. Zerumbone induced apoptosis in liver cancer cells via modulation of Bax/Bcl-2 ratio

    Directory of Open Access Journals (Sweden)

    Azimahtol Hawariah LP

    2007-04-01

    Full Text Available Abstract Background Zerumbone is a cytotoxic component isolated from Zingiber zerumbet Smith, a herbal plant which is also known as lempoyang. This new anticancer bioactive compound from Z. zerumbet was investigated for its activity and mechanism in human liver cancer cell lines. Results Zerumbone significantly showed an antiproliferative activity upon HepG2 cells with an IC50 of 3.45 ± 0.026 μg/ml. Zerumbone was also found to inhibit the proliferation of non-malignant Chang Liver and MDBK cell lines. However the IC50 obtained was higher compared to the IC50 for HepG2 cells (> 10 μg/ml. The extent of DNA fragmentation was evaluated by the Tdt-mediated dUTP nick end labelling assay which showed that, zerumbone significantly increased apoptosis in HepG2 cells in a time-course manner. In detail, the apoptotic process triggered by zerumbone involved the up-regulation of pro-apoptotic Bax protein and the suppression of anti-apoptotic Bcl-2 protein expression. The changes that occurred in the levels of this antagonistic proteins Bax/Bcl-2, was independent of p53 since zerumbone did not affect the levels of p53 although this protein exists in a functional form. Western blotting analysis for Bax protein was further confirmed qualitatively with an immunoassay that showed the distribution of Bax protein in zerumbone-treated cells. Conclusion Therefore, zerumbone was found to induce the apoptotic process in HepG2 cells through the up and down regulation of Bax/Bcl-2 protein independently of functional p53 activity.

  15. BAX and BAK1 are dispensable for ABT-737-induced dissociation of the BCL2-BECN1 complex and autophagy.

    Science.gov (United States)

    Pedro, Jose Manuel Bravo-San; Wei, Yongjie; Sica, Valentina; Maiuri, Maria Chiara; Zou, Zhongju; Kroemer, Guido; Levine, Beth

    2015-01-01

    Disruption of the complex of BECN1 with BCL2 or BCL2L1/BCL-XL is an essential switch that turns on cellular autophagy in response to environmental stress or treatment with BH3 peptidomimetics. Recently, it has been proposed that BCL2 and BCL2L1/BCL-XL may inhibit autophagy indirectly through a mechanism dependent on the proapoptotic BCL2 family members, BAX and BAK1. Here we report that the BH3 mimetic, ABT-737, induces autophagy in parallel with disruption of BCL2-BECN1 binding in 2 different apoptosis-deficient cell types lacking BAX and BAK1, namely in mouse embryonic fibroblasts cells and in human colon cancer HCT116 cells. We conclude that the BH3 mimetic ABT-737 induces autophagy through a BAX and BAK1-independent mechanism that likely involves disruption of BECN1 binding to antiapoptotic BCL2 family members.

  16. Bcl-2与IP3R相互作用调控肿瘤细胞程序性死亡的研究进展%IP3R/Bcl-2-channel complexes regulates programmed cell death

    Institute of Scientific and Technical Information of China (English)

    顾文文; 施韬; 顾一骅; 杨军

    2013-01-01

    由1,4,5-三磷酸肌醇受体(inositol 1,4,5-trisphosphate receptor,IP3R)介导的细胞内钙离子释放在细胞生理学过程中具有中枢性作用,其通道活性受到复杂信号网络的精细调节.近来有研究发现,IP3R是抗凋亡分子B细胞性淋巴瘤-2(B cell lymphoma-2,Bcl-2)家族蛋白的一个作用靶点,而抗凋亡Bcl-2蛋白作为IP3R的内源性调节分子,具有控制内质网中IP3R活性和抑制促凋亡钙信号的功能.已有研究证实,基于干扰Bcl-2家族成员与IP3R相互作用功能区域的多肽分子具有一定的抗肿瘤作用,因此,根据Bcl-2蛋白分子的结构特征及其与IP3R的相互作用机制而设计的靶向药物,已成为抗肿瘤新药的一个重要发展方向,并且部分药物已进入临床研究阶段.这些处于研发中的新药有望为慢性淋巴细胞白血病(chronic lymphocytic leukemia,CLL)等Bcl-2依赖性肿瘤的治疗及对抗Bcl-2介导的化疗放疗耐药现象带来新希望.本文旨在对上述研究的进展作一综述,以期为肿瘤细胞程序性死亡的调控机制的研究提供一些有价值的参考依据.%The Ca2+ release through IP3R (inositol 1,4,5-trisphosphate receptor) channels mediates the essential procedure of cellular functions.The process of Ca2+ release is elaborately regulated by the complex network system of signal transduction pathway.Recently,anti-apoptotic Bcl-2 proteins were reported to modulate Ca2+ gating of IP3R in ER (endoplasmic reticular) resulting in enhanced cellular bioenergetics and death resistance.Targeting Bcl-2-IP3R interaction was found to be able to induce apoptosis in vitro and in vivo.In addition,the natural or chemically synthesized compounds depending on the molecular structure of anti-apoptotic Bcl-2 proteins,have been tested in several clinical trials of chronic lymphocytic leukemia to verify their anti-tumor effect.Overall,current studies have provided some novel strategies of anti-tumor therapy involved in the

  17. Labdane type diterpenes down-regulate the expression of c-Myc protein, but not of Bcl-2, in human leukemia T-cells undergoing apoptosis.

    Science.gov (United States)

    Dimas, K; Demetzos, C; Vaos, V; Ioannidis, P; Trangas, T

    2001-06-01

    Sclareol (1) and ent-3beta-hydroxy-13-epi-manoyl oxide (2) belong to the labdane type diterpenes. They were isolated from the leaves and from the fruits of Cistus creticus subsp. creticus, and were found to be active against human leukemic cell lines. Compound 2 was converted to its thiomidazolide derivative (3). Compounds 1 and 3 were found to induce apoptotic cell death in human T-cell leukemia lines and to interfere with their cell cycle, arresting cells at G(0/1) phase. Apoptosis can involve the activation and/or suppression of critical genes such as c-myc whose reduction or its inappropriate expression can be associated with induction of cell death and bcl-2 whose activation prevents apoptosis in the latter case. In order to detect any concomitant effect (1 and 3) upon c-myc and bcl-2 oncogene expression, we performed Western blot analysis to determine the levels of expression of these two genes upon treatment with the above compounds. Western blot analysis showed that of c-myc proto-oncogene levels were markedly reduced before massive apoptosis ensued in H33AJ-JA1 and MOLT3 cells, while bcl-2 expression remained unaffected. Thus, induction of apoptosis due to compounds 1 and 3 in these T-cell leukemic cell lines is preceded by c-myc down regulation and furthermore sustained bcl-2 expression does not rescue cells from apoptosis under the conditions used. PMID:11337016

  18. Bcl-2 promotes malignant progression in a PDGF-B-dependent murine model of oligodendroglioma.

    Science.gov (United States)

    Doucette, Tiffany; Yang, Yuhui; Zhang, Wei; Fuller, Gregory N; Suki, Dima; Fults, Daniel W; Rao, Ganesh

    2011-11-01

    A significant subset of gliomas arises after activation of the proproliferative platelet-derived growth factor (PDGF) pathway. The progression of low-grade gliomas to more malignant tumors may be due to oncogenic cellular programs combining with those suppressing apoptosis. Antiapoptotic genes are overexpressed in a variety of cancers, and the antiapoptotic gene, BCL2, is associated with treatment resistance and tumor recurrence in gliomas. However, the impact of antiapoptotic gene expression to tumor formation and progression is unclear. We overexpressed Bcl-2 in a PDGFB-dependent mouse model of oligodendroglioma, a common glioma subtype, to assess its effect in vivo. We hypothesized that the antiapoptotic effect would complement the proproliferative effect of PDGFB to promote tumor formation and progression to anaplastic oligodendroglioma (AO). Here, we show that coexpression of PDGFB and Bcl-2 results in a higher overall tumor formation rate compared to PDGFB alone. Coexpression of PDGFB and Bcl-2 promotes progression to AO with prominent foci of necrosis, a feature of high-grade gliomas. Median tumor latency was shorter in mice injected with PDGFB and Bcl-2 compared to those injected with PDGFB alone. Although independent expression of Bcl-2 was insufficient to induce tumors, suppression of apoptosis (detected by cleaved caspase-3 expression) was more pronounced in AOs induced by PDGFB and Bcl-2 compared to those induced by PDGFB alone. Tumor cell proliferation (detected by phosphohistone H3 activity) was also more robust in high-grade tumors induced by PDGFB and Bcl-2. Our results indicate that suppressed apoptosis enhances oligodendroglioma formation and engenders a more malignant phenotype.

  19. 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.

  20. Der Einfluss der Anästhetika Sevofluran und Propofol auf die Regulation der apoptoseassoziierten Proteine Bax, Bcl-2, Mdm-2 und p53 nach inkompletter zerebraler Hemisphärenischämie bei der Ratte

    OpenAIRE

    Bachl, Monika Maria

    2005-01-01

    Der Einfluss der Anästhetika Sevofluran und Propofol auf apoptoseassoziierte Proteine während zerebraler Ischämie ist bisher nicht erforscht. In der vorliegenden Studie wurden die Effekte dieser Narkotika auf die Regulation der Apoptosefaktoren Bax, Bcl-2, Mdm-2 und p53 bei 36 narkotisierten Sprague-Dawley-Ratten untersucht, bei denen eine inkomplette zerebrale Hemisphärenischämie mit anschließender Reperfusion induziert wurde. Die Apoptosefaktoren wurden mittels Immunfluoreszenz- und Western...

  1. 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

  2. Prognostic Significance of Apoptosis Related Gene Family bcl-2 in Human Breast Cancer

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    To study the prognostic effect of bcl-2 oncogene and its gene family members bax, bcl-x expression in breast cancer patients. Methods: expression of bcl-2, bax proteins in 91 human breast cancer tissue sections were studied by immunohistochemical method. Bcl-x1 mRNA expression in frozen tissues from 16 breast cancer patients were detected using Northern blot method. Results: bcl-2 protein positivity was found in 60/91 (65.9%) patients, and bax positivity 59/91 (64.8%). Bcl-2 and bax expression levels were associated with apoptotic index(AI), histological grade, axillary lymph node metastasis, postoperative local recurrence and metastasis. Bcl-2 expression was related to ER positivity. In univariate analysis for disease free survival (DFS), bcl-2 and bax protein levels, and Al were all found to have prognostic value. The result of Cox's model multivariate analysis showed that bcl-2 protein level was an independent prognostic factor. In 16 frozen breast cancer tissues, 8/16(50%) had higher level of bcl-x1 mRNA, which showed correlation with bcl-2 protein expression and axillary lymph node metastasis. Conclusion: The findings indicate that dysregulated expressions of bcl-2, bax and bcl-x1 apoptosis-related genes, suggestive of serious deregulation of apoptotic process, may contribute to the biologic aggressiveness of breast cancer. Bcl-2 protein is an independent indicator of prognosis in breast cancer patients.

  3. Lentiviral-mediated delivery of Bcl-2 or GDNF protects against excitotoxicity in the rat hippocampus.

    Science.gov (United States)

    Wong, Liang-Fong; Ralph, G Scott; Walmsley, Lucy E; Bienemann, Alison S; Parham, Stephen; Kingsman, Susan M; Uney, James B; Mazarakis, Nicholas D

    2005-01-01

    Nutrient deprivation during ischemia leads to severe insult to neurons causing widespread excitotoxic damage in specific brain regions such as the hippocampus. One possible strategy for preventing neurodegeneration is to express therapeutic proteins in the brain to protect against excitotoxicity. We investigated the utility of equine infectious anemia virus (EIAV)-based vectors as genetic tools for delivery of therapeutic proteins in an in vivo excitotoxicity model. The efficacy of these vectors at preventing cellular loss in target brain areas following excitotoxic insult was also assessed. EIAV vectors generated to overexpress the human antiapoptotic Bcl-2 or growth factor glial-derived neurotrophic factor (GDNF) genes protected against glutamate-induced toxicity in cultured hippocampal neurons. In an in vivo excitotoxicity model, adult Wistar rats received a unilateral dose of the glutamate receptor agonist N-methyl-D-aspartate to the hippocampus that induced a large lesion in the CA1 region. Neuronal loss could not be protected by prior transduction of a control vector expressing beta-galactosidase. In contrast, EIAV-mediated expression of Bcl-2 and GDNF significantly reduced lesion size thus protecting the hippocampus from excitotoxic damage. These results demonstrate that EIAV vectors can be effectively used to deliver putative neuroprotective genes to target brain areas and prevent cellular loss in the event of a neurological insult. Therefore these lentiviral vectors provide potential therapeutic tools for use in cases of acute neurotrauma such as cerebral ischemia. PMID:15585409

  4. Targeting γ-herpesvirus 68 Bcl-2-mediated down-regulation of autophagy.

    Science.gov (United States)

    Su, Minfei; Mei, Yang; Sanishvili, Ruslan; Levine, Beth; Colbert, Christopher L; Sinha, Sangita

    2014-03-21

    γ-herpesviruses (γHVs) are common human pathogens that encode homologs of the anti-apoptotic cellular Bcl-2 proteins, which are critical to viral reactivation and oncogenic transformation. The murine γHV68 provides a tractable in vivo model for understanding general features of these important human pathogens. Bcl-XL, a cellular Bcl-2 homolog, and the murine γHV68 Bcl-2 homolog, M11, both bind to a BH3 domain within the key autophagy effector Beclin 1 with comparable affinities, resulting in the down-regulation of Beclin 1-mediated autophagy. Despite this similarity, differences in residues lining the binding site of M11 and Bcl-XL dictate varying affinities for the different BH3 domain-containing proteins. Here we delineate Beclin 1 differential specificity determinants for binding to M11 or Bcl-XL by quantifying autophagy levels in cells expressing different Beclin 1 mutants and either M11 or Bcl-XL, and we show that a G120E/D121A Beclin 1 mutant selectively prevents down-regulation of Beclin 1-mediated autophagy by Bcl-XL, but not by M11. We use isothermal titration calorimetry to identify a Beclin 1 BH3 domain-derived peptide that selectively binds to M11, but not to Bcl-XL. The x-ray crystal structure of this peptide bound to M11 reveals the mechanism by which the M11 BH3 domain-binding groove accommodates this M11-specific peptide. This information was used to develop a cell-permeable peptide inhibitor that selectively inhibits M11-mediated, but not Bcl-XL-mediated, down-regulation of autophagy.

  5. Protein Kinase B/Akt Binds and Phosphorylates PED/PEA-15, Stabilizing Its Antiapoptotic Action

    OpenAIRE

    Trencia, Alessandra; Perfetti, Anna; Cassese, Angela; Vigliotta, Giovanni; Miele, Claudia; Oriente, Francesco; Santopietro, Stefania; Giacco, Ferdinando; Condorelli, Gerolama; Formisano, Pietro; Beguinot, Francesco

    2003-01-01

    The antiapoptotic protein PED/PEA-15 features an Akt phosphorylation motif upstream from Ser116. In vitro, recombinant PED/PEA-15 was phosphorylated by Akt with a stoichiometry close to 1. Based on Western blotting with specific phospho-Ser116 PED/PEA-15 antibodies, Akt phosphorylation of PED/PEA-15 occurred mainly at Ser116. In addition, a mutant of PED/PEA-15 featuring the substitution of Ser116→Gly (PEDS116→G) showed 10-fold-decreased phosphorylation by Akt. In intact 293 cells, Akt also i...

  6. Methylmercury, an environmental electrophile capable of activation and disruption of the Akt/CREB/Bcl-2 signal transduction pathway in SH-SY5Y cells

    Science.gov (United States)

    Unoki, Takamitsu; Abiko, Yumi; Toyama, Takashi; Uehara, Takashi; Tsuboi, Koji; Nishida, Motohiro; Kaji, Toshiyuki; Kumagai, Yoshito

    2016-01-01

    Methylmercury (MeHg) modifies cellular proteins via their thiol groups in a process referred to as “S-mercuration”, potentially resulting in modulation of the cellular signal transduction pathway. We examined whether low-dose MeHg could affect Akt signaling involved in cell survival. Exposure of human neuroblastoma SH-SY5Y cells of up to 2 μM MeHg phosphorylated Akt and its downstream signal molecule CREB, presumably due to inactivation of PTEN through S-mercuration. As a result, the anti-apoptotic protein Bcl-2 was up-regulated by MeHg. The activation of Akt/CREB/Bcl-2 signaling mediated by MeHg was, at least in part, linked to cellular defence because either pretreatment with wortmannin to block PI3K/Akt signaling or knockdown of Bcl-2 enhanced MeHg-mediated cytotoxicity. In contrast, increasing concentrations of MeHg disrupted Akt/CREB/Bcl-2 signaling. This phenomenon was attributed to S-mercuration of CREB through Cys286 rather than Akt. These results suggest that although MeHg is an apoptosis-inducing toxicant, this environmental electrophile is able to activate the cell survival signal transduction pathway at lower concentrations prior to apoptotic cell death. PMID:27357941

  7. Changes of expression of apoptosis-related proteins Smac and Bcl-2 in Parkinsonˊs disease rat induced by Rotenone%鱼藤酮致帕金森病大鼠黑质中Smac和Bcl-2的表达及意义

    Institute of Scientific and Technical Information of China (English)

    张延平; 李彦改; 徐晓臣; 王英杰; 李印杰

    2015-01-01

    目的:研究鱼藤酮致帕金森病( Parkinsonˊs disease,PD)大鼠脑黑质中凋亡相关蛋白Smac和Bcl-2表达的改变。方法:将Witstar大鼠随机分为对照组和实验组。对照组10只背部皮下注射葵花油1ml/kg,实验组25只分为A、B、C三组,按照3.0(5只)、2.0(10只)和1.0(10只)mg/(kg·d)背部皮下注射鱼藤酮(鱼藤酮溶解在葵花籽油中,充分震荡混匀后4℃避光保存)。结果:透射电镜观察下,鱼藤酮处置的实验组神经元细胞皱缩,胞质致密,核染色质边集,有部分细胞胞核裂解,胞质芽突脱落,形成凋亡小体。并且随着鱼藤酮染毒剂量的增大,凋亡小体形成更加明显。免疫组化染色显示,Smac的阳性表达实验组高于对照组,Bcl-2的阳性表达实验组低于对照组。结论:鱼藤酮具有明显的神经毒性,能导致大鼠脑内DA能神经元的损伤,细胞凋亡参与了鱼藤酮帕金森模型大鼠黑质多巴胺神经细胞的损伤。%Objective:To study the changes of expression of apoptosis-related proteins Smac and Bcl-2 in the midbrain substantia nigra in Parkinsonˊs disease rat induced by Rotenone. Methods:Witstar rats were randomly divid-ed into control group and experimental group. Control group 10 rats were treated by subcutaneously injection of sun-flower oil 1ml/kg,25 in experimental group were divided into A,B,C three groups,with 3. 0(5),2. 0(10)and 1. 0 (10)mg/(kg·d)(subcutaneous injection of Rotenone dissolved in sunflower oil,shake evenly mixed 4℃ stored a-way from light). Results:TEM observated results,neuronal cells in experimental group shrinkage Rotenone treatment, cytoplasmic dense,the nuclear chromatin,nuclear fragmentation and some cells,cytoplasmic buds abscission,and for-mation of apoptotic bodies. And with the increase of the dose of Rotenone,apoptotic body formation was more obvious.Immunohistochemical staining showed positive expression of Smac

  8. 细胞凋亡调控蛋白bcl-2和bax在涎腺肿瘤中的表达及意义%Expression and significance of apoptosis regulatory protein bcl-2 and bax in tumor of salivary gland

    Institute of Scientific and Technical Information of China (English)

    齐红; 袁红民; 安文生; 杨荔琳

    2002-01-01

    目的:探讨bcl-2和bax基因蛋白在涎腺肿瘤(Salivary tumer,ST)中表达及意义.方法:SABC法观察87例ST及12例正常涎腺组织(Natural salivary tissue,NST)中bcl-2及bax表达.结果:bcl-2及bax蛋白在ST中表达明显高于NST;bcl-2在涎腺恶性肿瘤(Salivary malignacy,SM)中表达明显高于良性肿瘤;SM中bcl-2表达与其恶性程度及临床分期显著相关;bax蛋白表达与SM临床病理指标均无相关性.结论:bcl-2蛋白表达有助于SM恶性程度判断;可作为判断SM生物特性、临床分期的重要指标;bax/bcl-2比率变化参与了ST发生及发展过程.

  9. Targeting BCL-2 and ABL/LYN in Philadelphia chromosome-positive acute lymphoblastic leukemia.

    Science.gov (United States)

    Leonard, Jessica T; Rowley, Joelle S J; Eide, Christopher A; Traer, Elie; Hayes-Lattin, Brandon; Loriaux, Marc; Spurgeon, Stephen E; Druker, Brian J; Tyner, Jeffrey W; Chang, Bill H

    2016-08-31

    Treatment of Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph(+)ALL) remains a challenge. Although the addition of targeted tyrosine kinase inhibitors (TKIs) to standard cytotoxic therapy has greatly improved upfront treatment, treatment-related morbidity and mortality remain high. TKI monotherapy provides only temporary responses and renders patients susceptible to the development of TKI resistance. Thus, identifying agents that could enhance the activity of TKIs is urgently needed. Recently, a selective inhibitor of B cell lymphoma 2 (BCL-2), ABT-199 (venetoclax), has shown impressive activity against hematologic malignancies. We demonstrate that the combination of TKIs with venetoclax is highly synergistic in vitro, decreasing cell viability and inducing apoptosis in Ph(+)ALL. Furthermore, the multikinase inhibitors dasatinib and ponatinib appear to have the added advantage of inducing Lck/Yes novel tyrosine kinase (LYN)-mediated proapoptotic BCL-2-like protein 11 (BIM) expression and inhibiting up-regulation of antiapoptotic myeloid cell leukemia 1 (MCL-1), thereby potentially overcoming the development of venetoclax resistance. Evaluation of the dasatinib-venetoclax combination for the treatment of primary Ph(+)ALL patient samples in xenografted immunodeficient mice confirmed the tolerability of this drug combination and demonstrated its superior antileukemic efficacy compared to either agent alone. These data suggest that the combination of dasatinib and venetoclax has the potential to improve the treatment of Ph(+)ALL and should be further evaluated for patient care. PMID:27582059

  10. siRNA-based targeting of antiapoptotic genes can reverse chemoresistance in P-glycoprotein expressing chondrosarcoma cells

    Directory of Open Access Journals (Sweden)

    Yang Jay

    2009-05-01

    Full Text Available Abstract Background High expression of P-glycoprotein is one of the well-known mechanisms of chemoresistance in chondrosarcomas. However, the role of antiapoptotic proteins, a common mechanism responsible for chemoresistance in other tumors, has not been well studied in chondrosarcomas. We examined the importance of P-glycoprotein and antiapoptotic proteins in the chemoresistance to doxorubicin of two Grade II chondrosarcoma cell lines, JJ012 and SW1353. Results We confirmed that both chondrosarcoma cell types expressed P-glycoprotein and antiapoptotic proteins (Bcl-2, Bcl-xL and XIAP. siRNA knockdown as well as pharmacologic inhibitors of cell survival proteins (Bcl-2, Bcl-xL and XIAP enhanced apoptosis of chemoresistant chondrosarcoma cells by up to 5.5 fold at 0.1 μmol and 5.5 fold at 1 μmol doxorubicin. These chemosensitizing effects were comparable to those of P-glycoprotein inhibition by siRNA or pharmacologic inhibitor. Conclusion These findings suggest that antiapoptotic proteins play a significant role in the chemoresistance of chondrosarcoma cells independent of P-glycoprotein. Based on the results, a new siRNA-based therapeutic strategy targeting antiapoptotic genes can be designed to overcome the chemoresistance of chondrosarcomas which is often conferred by P-glycoprotein.

  11. Copper Induces Apoptosis of Neuroblastoma Cells Via Post-translational Regulation of the Expression of Bcl-2-family Proteins and the tx Mouse is a Better Model of Hepatic than Brain Cu Toxicity.

    Science.gov (United States)

    Chan, Hsien W; Liu, Tianbing; Verdile, Giuseppe; Bishop, Glenda; Haasl, Ryan J; Smith, Mark A; Perry, George; Martins, Ralph N; Atwood, Craig S

    2008-01-01

    The basic mechanism(s) by which altered Cu homeostasis is toxic to hepatocytes and neurons, the two major cell types affected in copper storage diseases such as Wilson's disease (WD), remain unclear. Using human M17 neuroblastoma cells as a model to examine Cu toxicity, we found that there was a time- and concentration-dependent induction of neuronal death, such that at 24 h there was a approximately 50 % reduction in viability with 25 muM Cu-glycine(2). Cu-glycine(2) (25:50 muM) treatment for 24 h significantly altered the expression of 296 genes, including 8 genes involved with apoptosis (BCL2-associated athanogene 3, BCL2/adenovirus E1B 19kDa interacting protein caspase 5, regulator of Fas-induced apoptosis, V-jun sarcoma virus 17 oncogene homolog, claudin 5, prostaglandin E receptor 3 and protein tyrosine phosphatase, non-receptor type 6). Surprisingly, changes in the expression of more 'traditional' apoptotic genes (Bcl-2, Bax, Bak and Bad) did not vary more than 20 %. To test whether the induction of apoptosis in neuroblastoma cells was via post-translational mechanisms, we measured the protein expression of these apoptotic markers in M17 neuroblastoma cells treated with Cu-glycine(2) (0-100 muM) for 24-48 h. Compared with glycine treated cells, Cu-glycine(2) reduced Bcl-2 expression by 50 %, but increased Bax and Bak expression by 130% and 400 %, respectively. To assess whether Cu also induced apoptotic cell death in a mouse model of WD, we measured the expression of these apoptotic markers in the liver and brain of mice expressing an ATP7b gene mutation (tx(J) mice) at 10 months of age (near the end of their lives when overt liver pathology is displayed). Changes in the liver expression of these apoptotic markers in tx(J) mice compared to background mice mirrored those of Cu treated neuroblastoma cells. In contrast, few changes in apoptotic protein expression were detected in the brain between tx(J) and background mice, indicating the tx(J) mouse is a good

  12. Ganoderma lucidum spore powder modulates Bcl-2 and Bax expression in the hippocampus and cerebral cortex, and improves learning and memory in pentylenetetrazole-kindled rats

    Institute of Scientific and Technical Information of China (English)

    Shuang Zhao; Shengchang Zhang; Shuqiu Wang

    2011-01-01

    We studied the effects of Ganoderma lucidum spore powder on Bax and Bcl-2 expression and neuronal apoptosis in pentylenetetrazole-kindled epileptic rats. Sixty adult rats were randomly divided into a control group, an epileptic group (kindled) and three medication groups ( 150, 300,450 mg/kg given to kindled rats). Bax and Bcl-2 immunohistochemistry and TUNEL labeling show ed that the number of Bax- and TUNEL-positive cells in the hippocampus and cerebral cortex decreased significantly in the high-dose medication group, while the number of Bcl-2immunoreactive cells increased. The Morris water maze test showed that high-dose treatment significantly shortened escape latency and increased spatial probe trial performance. Our findings indicate that a high dose of Ganoderma lucidum spore powder upregulates the expressionof antiapoptotic Bcl-2 protein in the hippocampus and cerebral cortex, inhibits proapoptotic Bax expression, and decreases seizure-induced neuronal apoptosis. Further,Ganoderma lucidum appears to protect against epilepsy-related learning and memory impairments.

  13. P53蛋白和Bcl-2蛋白在环孢菌素和硝苯地平龈增生中的表达%Expression of P53 Protein and Bcl-2 Protein in Gingival Hyperplasia Induced by Cyclosporine and Nifedipine

    Institute of Scientific and Technical Information of China (English)

    王美娟; 孙卫斌; 刘卫红; 朱庆萍

    2004-01-01

    目的探讨凋亡相关蛋白P53、Bcl-2在药物性龈增生中的表达及意义.方法用免疫组化SP法检测17例环孢菌素性龈增生、5例硝苯地平性龈增生牙龈中P53和Bcl-2蛋白的表达,8例正常人牙龈作对照.结果17例环孢菌素性龈增生中有11例、5例硝苯地平性龈增生中有3例的牙龈上皮中有P53蛋白的阳性表达,而对照组均无P53蛋白的表达.Bcl-2蛋白在环孢菌素及硝苯地平性龈增生的牙龈上皮中,表达比较明显,而在对照组的牙龈上皮中,染色明显偏淡.结论本研究结果中P53和Bcl-2蛋白表达增强,提示细胞凋亡抑制可能在药物性龈增生的发病中起作用.

  14. Study on the Regulation of Bcl-2 Gene on Rat Spermatogenic Cells Apoptosis in Transcription Level

    Institute of Scientific and Technical Information of China (English)

    董强; 杨宇如; 黄明孔; 李虹; 张卫东; 徐震波

    2000-01-01

    Objective To detect the change of Bcl-2 gene expression in the apopototic process of spermatogenic cells in rat with vasoligation and vasostomy, and to find out the relationship between the transcription of Bcl-2 and the apoptosis of spermatognic cells.Materials & Methods Sixty adult male Sprague-Dawley rats in 3 groups were operated with vasoligation and vasostomy. Then hybridization in situ with hypersensitive Bcl-2 RNA probe was used to detect the change of Bcl-2 mRNA.Results The transcription of Bcl-2 gene in spermatogenic cells was obviously inhibited in the vasoligation group compared with that in the control group (P<0. 05), and the transcription in the vasostomy group showed no difference from that of the control group.Conclusion Bcl-2 gene has an anti-apoptotic effect in rats with vasostomy, and there was a transcriptional regulation of Bcl-2 gene in rat spermatogenic cell during the period of pre-vasoligation to post-vasoligation and to post-vasosotomy.

  15. Genetic Variation in BCL2 3′-UTR Was Associated with Lung Cancer Risk and Prognosis in Male Chinese Population

    OpenAIRE

    Xu, Ping; Liu, Li; Wang, Jianzhong; Zhang, Kai; Hong, Xiaohua; Deng, Qifei; Xiang, Jingjun; Zhang, Xiaomin; He, Meian; WU, TANGCHUN; Guo, Huan

    2013-01-01

    Objectives Bcl-2 is a critical apoptosis inhibitor with established carcinogenic potential, and can confer cancer cell resistance to therapeutic treatments by activating anti-apoptotic cellular defense. We hypothesized that genetic variants of BCL2 gene may be associated with lung cancer susceptibility and prognosis. Methods Three selected tagSNPs of BCL2 (rs2279115, rs1801018, and rs1564483) were genotyped in 1017 paired male Chinese lung cancer cases and controls by TaqMan assay. The associ...

  16. Mitochondrial genome depletion in human liver cells abolishes bile acid-induced apoptosis: role of the Akt/mTOR survival pathway and Bcl-2 family proteins.

    Science.gov (United States)

    Marin, Jose J G; Hernandez, Alicia; Revuelta, Isabel E; Gonzalez-Sanchez, Ester; Gonzalez-Buitrago, Jose M; Perez, Maria J

    2013-08-01

    Acute accumulation of bile acids in hepatocytes may cause cell death. However, during long-term exposure due to prolonged cholestasis, hepatocytes may develop a certain degree of chemoresistance to these compounds. Because mitochondrial adaptation to persistent oxidative stress may be involved in this process, here we have investigated the effects of complete mitochondrial genome depletion on the response to bile acid-induced hepatocellular injury. A subline (Rho) of human hepatoma SK-Hep-1 cells totally depleted of mitochondrial DNA (mtDNA) was obtained, and bile acid-induced concentration-dependent activation of apoptosis/necrosis and survival signaling pathways was studied. In the absence of changes in intracellular ATP content, Rho cells were highly resistant to bile acid-induced apoptosis and partially resistant to bile acid-induced necrosis. In Rho cells, both basal and bile acid-induced generation of reactive oxygen species (ROS), such as hydrogen peroxide and superoxide anion, was decreased. Bile acid-induced proapoptotic signals were also decreased, as evidenced by a reduction in the expression ratios Bax-α/Bcl-2, Bcl-xS/Bcl-2, and Bcl-xS/Bcl-xL. This was mainly due to a downregulation of Bax-α and Bcl-xS. Moreover, in these cells the Akt/mTOR pathway was constitutively activated in a ROS-independent manner and remained similarly activated in the presence of bile acid treatment. In contrast, ERK1/2 activation was constitutively reduced and was not activated by incubation with bile acids. In conclusion, these results suggest that impaired mitochondrial function associated with mtDNA alterations, which may occur in liver cells during prolonged cholestasis, may activate mechanisms of cell survival accounting for an enhanced resistance of hepatocytes to bile acid-induced apoptosis. PMID:23597504

  17. Relaxin has anti-apoptotic effects on human trophoblast-derived HTR-8/SV neo cells.

    Science.gov (United States)

    Lodhi, Romana S Z; Nakabayashi, Koji; Suzuki, Kaho; Yamada, Ai Y; Hazama, Rhoichi; Ebina, Yasuhiko; Yamada, Hideto

    2013-12-01

    The study was conducted to evaluate the effects of human relaxin on apoptosis in the human trophoblast derived HTR-8/SV neo cell line, which is a possible model of human extravillous trophoblasts (EVTs). HTR-8/SV neo cells, cultured in phenol red free RPMI1640 medium, were treated with different doses of human recombinant (rH2) relaxin in serum-deprived conditions. RT-PCR was used for evaluating relaxin receptor: RXFP1 and RXFP2 expression in HTR-8/SV neo cells. The cell death was examined by TUNEL assay. Furthermore, we investigated caspase-3, cleaved PARP and Bcl-2 expressions by Western blot analysis to recognize the translational effects of anti-apoptotic and pro-apoptotic proteins. RXFP1 and RXFP2 mRNA expression was observed in HTR-8/SV neo cells. Compared with untreated control cultures, treatment with rH2 relaxin, decreased TUNEL-positive rate in HTR-8/SV neo cells was observed. Western blot analysis revealed that treatment with rH2 relaxin decreased the expression of caspase-3 and cleaved PARP, but in contrast increased Bcl-2 expression in those cells. These results suggest that rH2 relaxin has anti-apoptotic effects on HTR8/SV neo cells by decreasing pro-apoptotic caspase-3 and cleaved PARP expression and up-regulating anti-apoptotic Bcl-2 expression. PMID:24070111

  18. Acidosis Promotes Bcl-2 Family-mediated Evasion of Apoptosis

    Science.gov (United States)

    Ryder, Christopher; McColl, Karen; Zhong, Fei; Distelhorst, Clark W.

    2012-01-01

    Acidosis arises in solid and lymphoid malignancies secondary to altered nutrient supply and utilization. Tumor acidosis correlates with therapeutic resistance, although the mechanism behind this effect is not fully understood. Here we show that incubation of lymphoma cell lines in acidic conditions (pH 6.5) blocks apoptosis induced by multiple cytotoxic metabolic stresses, including deprivation of glucose or glutamine and treatment with dexamethasone. We sought to examine the role of the Bcl-2 family of apoptosis regulators in this process. Interestingly, we found that acidic culture causes elevation of both Bcl-2 and Bcl-xL, while also attenuating glutamine starvation-induced elevation of p53-up-regulated modulator of apoptosis (PUMA) and Bim. We confirmed with knockdown studies that these shifts direct survival decisions during starvation and acidosis. Importantly, the promotion of a high anti- to pro-apoptotic Bcl-2 family member ratio by acidosis renders cells exquisitely sensitive to the Bcl-2/Bcl-xL antagonist ABT-737, suggesting that acidosis causes Bcl-2 family dependence. This dependence appears to be mediated, in part, by the acid-sensing G protein-coupled receptor, GPR65, via a MEK/ERK pathway. PMID:22685289

  19. Bcl-2 associated with severity of manic symptoms in bipolar patients in a manic phase.

    Science.gov (United States)

    Chen, Wei-Ting; Huang, Tiao-Lai; Tsai, Meng-Chang

    2015-02-28

    B cell lymphoma protein-2 (Bcl-2) may contribute to the pathophysiology of bipolar disorder, and may be involved in the therapeutic action of anti-manic drugs. The aim of this study was to investigate serum levels of Bcl-2 in bipolar patients in a manic phase, and evaluate the Bcl-2 changes after treatment. We consecutively enrolled 23 bipolar inpatients in a manic phase and 40 healthy subjects; 20 bipolar patients were followed up with treatment. Serum Bcl-2 levels were measured with assay kits. All 20 patients were evaluated by examining the correlation between Bcl-2 levels and Young Mania Rating Scale (YMRS) scores, using Spearman׳s correlation coefficients. The serum Bcl-2 levels in bipolar patients in a manic phase were higher than in healthy subjects, but without a significant difference. The YMRS scores were significantly negatively associated with serum Bcl-2 levels (p=0.042). Bcl-2 levels of the 20 bipolar patients were measured at the end of treatment. Using the Wilcoxon Signed Rank test, we found no significant difference in the Bcl-2 levels of bipolar patients after treatment. Our results suggest that Bcl-2 levels might be an indicator of severity of manic symptoms in bipolar patients in a manic phase. PMID:25563670

  20. Effects of Treatment with Platinum Azidothymidine and Azidothymidine on Telomerase Activity and Bcl-2 Concentration in Hepatocellular Carcinoma- Induced Rats

    OpenAIRE

    Sabokrouh, Abdolreza; Goodarzi, Mohammad Taghi; Vaisi-raygani, Asad; Shohreh KHATAMI*; TAGHIZADEH-JAHED, MASOUD

    2014-01-01

    Background Telomerase activity increases in cancer cells. Bcl-2 is an antiapoptotic factor that its concentration grows in many cancer cells including hepato-cellular carcinoma cells. In this study, an attempt was made to investigate the effects of a new synthetic compound, platinum azidothymidine (Pt-AZT) on treatment of rats with Hepatocellular Carcinoma (HCC) and to compare its effects with azidothymidine (AZT) in alteration of telomerase activity and Bcl-2 concentration in HCC. Methods He...

  1. Expression of Bcl2 proto-oncogene in primary tumors of the central nervous system.

    Directory of Open Access Journals (Sweden)

    Tyagi D

    2002-07-01

    Full Text Available The present study was addressed to find out the expression of Bcl2 proto-oncogene in tumor tissues derived from 25 patients with primary central nervous system tumors. Brain parenchyma in 8 cases, with deeply located tumor, was also examined for Bcl2 expression which served as control. Both benign and malignant tumors (confirmed by histopathological examination expressed Bcl2 gene product. Tumors exhibited 2-6 fold increase in Bcl2 expression as compared to the normal parenchyma adjacent to some of these tumors studied. However, no correlation was found between the histopathological types of tumor, glial fibrillary acidic protein positivity and degree of Bcl2 expression. Based on this study, we propose that the overexpression of Bcl2 gene product found in primary CNS tumors may be an important molecular event which is known to make the various types of tumor resistant to chemotherapy or radiotherapy.

  2. Expression of Bcl-2 inhibited Fas-mediated apoptosis in human hepatocellular carcinoma BEL-7404 cells

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Apoptosis plays an important role in embryonic development, tissue remodeling, immune regulation and tumor regression. Two groups of molecules (Bcl-2 family and"Death factor"family) are involved in regulating apoptosis. In order to know about the effect of Bcl-2 on apoptosis induced by Fas, a typical member of"Death factor" family, the transfection experiments with expression vectors pcDNA3-fland pcDNA3-bcl-2 were performed in BEL-7404 cells, a human hepatocellular carcinoma cell line which expresses endogenous Fas, but not FasL and Bcl2. The data showed that the expression of FasL in pcDNA3fl transfected hepatoma cells obviously induced the apoptosis of the cells. However, the overexpression of Bcl-2 in pcDNA3bcl-2 transfected 7404/b-16 cells counteracted pcDNA3-fltransient transfection mediated apoptosis. Further study by cotransfection experiments indicated that Bid but not Bax (both were pro-apoptotic proteins of Bcl-2 family) blocked the inhibitory effect of Bcl-2 on Fas-mediated apoptosis. These results suggested that Fas-mediated apoptosis in human hcpatoma cells is possibly regulated by Bcl-2 family proteins via mitochondria pathway.

  3. Host cell Golgi anti-apoptotic protein (GAAP) and growth of Chlamydia pneumoniae.

    Science.gov (United States)

    Markkula, Eveliina; Hulkkonen, Jaakko; Penttilä, Tuula; Puolakkainen, Mirja

    2013-01-01

    Chlamydia pneumoniae protein CPn0809 is a type three secretion system substrate, the exact function of which in infection pathogenesis has remained unknown. In this study, we identified by yeast two-hybrid screening a potential host cell interaction partner of CPn0809, Golgi anti-apoptotic protein (GAAP), a conserved protein found in eukaryotic cells. GAAP gene is expressed at relatively constant levels and its expression remained stable also after C. pneumoniae infection. The interaction between GAAP and C. pneumoniae was suggested by transfection studies. GAAP knock-down by siRNA in infected A549 cells resulted in an increased number of C. pneumoniae genomes and growth of the bacteria as judged by quantitative PCR and inclusion counts, respectively. Silencing of GAAP did not make the A549 cells more susceptible to apoptosis per se, and infection with C. pneumoniae prevented staurosporin-induced apoptosis also in transfected cultures. Taken together, the proposed interaction between C. pneumoniae and GAAP modulates bacterial growth in A549 cells. PMID:23000903

  4. Predictive value of bcl-2 immunoreactivity in prostate cancer patients treated with radiotherapy

    International Nuclear Information System (INIS)

    Background and purpose: Recent experimental evidence suggests that overexpression of bcl-2, a protein functioning by blocking apoptosis, may influence the treatment outcome in human tumours, including prostate cancer. To test the clinical implications of this hypothesis, tumours from patients with prostate cancer treated with external beam radiotherapy were investigated for bcl-2 immunoreactivity (IR) and correlated with prognosis and treatment outcome. Materials and methods: Bcl-2 IR was evaluated in archival tumour specimens obtained through transurethral resection from 42 patients with localized prostate cancer (T0-T4, N0 and M0). Bcl-2 IR expression was related to stage, grade and cancer-specific survival. Specimens were obtained prior to administrating routine radiotherapy for all patients. Results: Bcl-2 IR was present in 19/42 (45%) tumours. The bcl-2-positive patients had a significantly longer cancer-specific survival than the bcl-2-negative patients (10.3 versus 3.4 years, P<0.04). At follow-up (7-19 years), nine patients were still alive, 26 patients had died of prostate cancer and seven patients had died of other causes. Conclusions: This study indicates that pre-treatment bcl-2 overexpression is related to a favourable outcome in prostate cancer treated with radiotherapy. Low bcl-2 along with a high stage may be a predictor of poor prognosis and these patients might benefit from additional treatment. (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

  5. Clinicophatological features of non-hodgkin's lymphoma in children and the relationship of LMP-1 and P53、bcl-2 protein expression%儿童非霍奇金淋巴瘤EB病毒LMP-1和P53、bcl-2表达的关系

    Institute of Scientific and Technical Information of China (English)

    黄波; 郭瑞珍; 明晓务; 王俊; 李青; 唐文台; 肖庆帮

    2003-01-01

    目的探讨儿童NHL EB病毒LMP-1和P53、bcl-2蛋白的表达及关系.方法采用免疫组化Envision法检测64例儿童NHL中LMP-1和P53、bcl-2蛋白.结果 (1)P53蛋白阳性表达39例(60.9%),表达强度与淋巴瘤恶性程度呈正相关;阳性表达率在低恶组与中、高恶性组间有显著性意义,P<0.01.bcl-2蛋白阳性表达37例(53.8%),bcl高于TCL,低恶性高于高恶性.(2)LMP-1蛋白阳性表达45例(70.3%),阳性表达率与肿瘤恶性程度和年龄有统计学意义,P<0.01;而与淋巴瘤免疫表型、性别和发病部位无关.LMP-1表达与P53及bcl-2的表达呈正相关.结论 EBV感染是儿童NHL发生发展不可忽视的病毒致病因素,其致病作用可能是通过上调P53、bcl-2蛋白实现的.

  6. A component of green tea (-)-epigallocatechin-3-gallate, promotes apoptosis in T24 human bladder cancer cells via modulation of the PI3K/Akt pathway and Bcl-2 family proteins

    International Nuclear Information System (INIS)

    Bladder cancer is the fourth most common cancer in men and ninth most common in women. It has a protracted course of progression and is thus an ideal candidate for chemoprevention strategies and trials. This study was conducted to evaluate the chemopreventive/antiproliferative potential of (-)-epigallocatechin gallate (EGCG, the major phytochemical in green tea) against bladder cancer and its mechanism of action. Using the T24 human bladder cancer cell line, we found that EGCG treatment caused dose- and time-dependent inhibition of cellular proliferation and cell viability, and induced apoptosis. Mechanistically, EGCG inhibits phosphatidylinositol 3'-kinase/Akt activation that, in turn, results in modulation of Bcl-2 family proteins, leading to enhanced apoptosis of T24 cells. These findings suggest that EGCG may be an important chemoprevention agent for the management of bladder cancer

  7. Expression of bcl-2 in the Epithelial Lining of Odontogenic Keratocysts

    Directory of Open Access Journals (Sweden)

    Gh. Jahanshahi

    2006-03-01

    Full Text Available Statement of Problem: The aggressive nature and high recurrence rate of Odontogenic Keratocysts (OKCs may be due to unknown factors inherent in the epithelium or because of enzymatic activity in the fibrous wall. Bcl-2 protein is characterized by its ability to inhibit apoptosis.Purpose: The aim of the present study was to analyze the expression of bcl-2 protein in OKCs and to compare it with the more common radicular and dentigerous cysts. The possible relationship between inflammation and bcl-2 expression was also investigated.Materials and Methods: Formalin fixed paraffin-embedded tissue sections of 20 OKCs, 20 radicular and 20 dentigerous cysts were immunohistochemically analyzed for immunoreactivity of the bcl-2 protein.Results: Bcl-2 expression was observed in 19 OKCs (95%, one radicular cyst (5%and one dentigerous cyst (5%. There was no statistically significant relationship between inflammation and the number of bcl-2 positive cells. Immunoreactivity was mainly noted in the basal or basal/supra basal layers.Conclusion: Considering the fact that bcl-2 over expression may lead to increased survival of epithelial cells, present study may demonstrate a possible relationship between the aggressive nature of OKC and the intrinsic growth potential of its lining epithelium. Furthermore a basal/supra basal distribution of bcl-2 positive cells was seen in some odontogenic keratocysts which may have a significant impact on the behavior of this cyst.

  8. Expression of Bcl-2 and Bax in extrahepatic biliary tract carcinoma and dysplasia

    Institute of Scientific and Technical Information of China (English)

    Sheng-Mian Li; Shu-Kun Yao; Nobuyoshi Yamamura; Toshitsugu Nakamura

    2003-01-01

    AIM: To compare the difference of expression of Bcl-2 and Bax in extrahepatic biliary tract carcinoma and dysplasia, and to analyze the role of Bcl-2 and Bax proteins in the progression from dysplasia to carcinoma and to evaluate the correlation of Bcl-2/Bax protein expression with the biological behaviors.METHODS: Expressions of Bcl-2 and Bax were examined immunohistochemically in 27 cases of extrahepatic biliary tract carcinomas (bile duct carcinoma: n=21, carcinoma of ampulla of Vater: n=6), and 10 cases of atypical dysplasia.Five cases of normal biliary epithelial tissues were used as controls. A semiquantitative scoring system was used to assess the Bcl-2 and Bax reactivity.RESULTS: The expression of Bd-2 was observed in 10 out of 27 (37.0 %) invasive carcinomas, 1 out of 10 clysplasias, none out of 5 normal epithelial tissues. Bax expression rate was 74.1% (20/27) in invasive carcinoma, 30 % (3/10) in dysplasia,and 40 % (2/5) in normal biliary epithelium. Bcl-2 and Bax activities were more intense in carcinoma than in dysplasia,with no significant difference in Bcl-2 expression (P=0.1:10),and significant difference in Bax expression (P=0.038). Level of Bax expression was higher in invasive carcinoma than in dysplasia and normal tissue (P=0.012). Bcl-2 expression was correlated to Bax expression (P=0.0059). However, Bcl-2/Bax expression had no correlation with histological subtype,grade of differentiation, or level of invasion.CONCLUSION: Increased Bcl-2/Bax expression from dysplasia to invasive tumors supports the view that this is the usual route for the development of extrahepatic biliary tract carcinoma. Bcl-2/Bax may be involved, at least in part,in the apoptotic activity in extrahepatic biliary carcinoma.

  9. Overexpression of the anti-apoptotic protein AVEN contributes to increased malignancy in hematopoietic neoplasms.

    Science.gov (United States)

    Eißmann, M; Melzer, I M; Fernández, S B M; Michel, G; Hrabě de Angelis, M; Hoefler, G; Finkenwirth, P; Jauch, A; Schoell, B; Grez, M; Schmidt, M; Bartholomae, C C; Newrzela, S; Haetscher, N; Rieger, M A; Zachskorn, C; Mittelbronn, M; Zörnig, M

    2013-05-16

    AVEN has been identified as an inhibitor of apoptosis, which binds to the adaptor protein, APAF-1, and thereby prevents apoptosome formation and mitochondrial apoptosis. Recent data have demonstrated high expression levels of AVEN messenger RNA in acute leukemias as well as a positive correlation between AVEN mRNA overexpression and poor prognosis in childhood acute lymphoblastic leukemia. On the basis of these data, we investigated the potential involvement of AVEN in tumorigenesis. First, we confirmed the overexpression of AVEN in T-cell acute lymphoblastic leukemia/lymphoma (T-ALL) patient samples. We then established a transgenic mouse model with T-cell-specific overexpression of AVEN, with which we demonstrated the oncogenic cooperation of AVEN with heterozygous loss of p53. Finally, we used a subcutaneous xenograft mouse model to show that AVEN knockdown in the T-ALL cell lines, MOLT-4 and CCRF-CEM, and in the acute myeloblastic leukemia cell line, Kasumi-1, leads to a halt in tumor growth owing to the increased apoptosis and decreased proliferation of tumor cells. Collectively, our data demonstrate that the anti-apoptotic molecule, AVEN, functions as an oncoprotein in hematopoietic neoplasms. PMID:22751129

  10. Differential regulation of pro- and antiapoptotic proteins in fish adipocytes during hypoxic conditions.

    Science.gov (United States)

    Ekambaram, Padmini; Parasuraman, Parimala; Jayachandran, Tharani

    2016-06-01

    Worldwide, the frequencies and magnitudes of hypoxic events in estuarine waters have increased considerably over the past two decades. Fish populations are suitable indicators for the assessment of quality of aquatic ecosystems and often comprise a variety of adaptation systems by triggering oxidants, antioxidants and hypoxia-responsive signaling proteins. Signaling pathway may lead to cell survival or cell death which is fine-tuned by both positive and negative factors, which includes hypoxia-inducible factor-1α (HIF1α), heat-shock protein-70 (HSP70), phospho-c-Jun N-terminal kinase 1/2 (p-JNK1/2) and apoptosis signal-regulating kinase-1 (ASK1). In the present study, we attempt to determine stress-mediated signaling changes and molecular mechanism behind the cell survival by comparing adipocytes of fish from field hypoxic condition and laboratory-induced hypoxic condition (in vitro hypoxia). Comparison of field and laboratory studies in fish adipocytes showed differential expression of HIF1α, HSP70, p-JNK1/2 and ASK1 with altered oxidants and antioxidants. Further, the results also suggest that in vitro hypoxic conditions mimic field hypoxic conditions. Trends of hypoxia response were same in in vitro hypoxia of control adipocytes as in Ennore estuary, and hypoxia response was more pronounced in the test adipocytes under in vitro hypoxic condition. Results of the present work suggest that hypoxia is the major crusade of water pollutants affecting fish by differential regulation of pro- and antiapoptotic proteins probably through HSP70. This may play a vital role by providing cytoprotection in pollutant-induced stressed fish adipocytes substantiated by the in vitro hypoxic studies. PMID:26744268

  11. Effect of soluble CD44 molecule on the expression of apoptosis regulatory protein bcl-2 associated death factor bad in human trabecular meshwork cell%可溶性CD44分子对人眼小梁网细胞凋亡调节蛋白bcl-2相关死亡因子bad表达的影响

    Institute of Scientific and Technical Information of China (English)

    梁宗宝; 吴瑜瑜; 郭茂生

    2012-01-01

    亡因子bad蛋白的表达.%Background Researches demonstrated that the levels of soluble CD44 (sCD44)molecule in aqueous is significantly higher in primary open-angle glaucomous(POAG) eye than normal eye,but how the sCD44 would affect the expression of apoptosis protein in trabecular meshwork cells is below understanding. Objective The present study was to investigate the effect of sCD44 on the expression of regulatory proteins bcl-2 associated death factor bad in trabecular meshwork cells in the patients with POAG. Methods Human scleral tissue with trabecular meshwork were obtained from POAG patients during the surgery.The trabecular meshwork cells were primarily cultured by explant culture method and identified by immunochemistry.The third generation of cells were incubated with free-serum DMEM/F12 medium added differnt dosages of sCD44 (0,1,5,10,25,50 mg/L) for 48 hours.The expression of bad protein in cultured cells was detected using cell counting kit-8 (CCK-8) as the absorbance values at 490 nm(A,90 value),and the bad protein level in cultured cells was assayed by ELISA. Results The cultured cells showed the positive response for laminin ( LM ),neuron specific enolase ( NSE ),fibronectin ( FN ) monoclonal antibodies.The CCK-8 assay showed that the A490 values of the trabecular meshwork cells in 0,1,5,10,25,50 μg/L of sCD44 groups were 0.2460±0.0019,0.1874±0.0015,0.1570±0.0016,0.1302±0.0019,0.1084±0.0018,0.0940±0.0020 respectively with a statistically significant difference among the 6 groups( F =14.922,P =0.000 ),and the A490 values in various dosages of sCD44 groups were significantly lower than the 0 μg/L sCD44 group (P=0.013,0.008,0.011,0.005,0.004).The ELISA assay showed that bad protein levels in 0,1,5,10,25,50 μg/L of sCD44 groups were ( 114.8461 ± 2.9560 ),( 137.8270 ± 2.4259 ),( 161.4194 ± 3.7381 ),( 170.9453 ± 3.2006 ),( 221.2252 ±4.3738 ),( 324.6167±4.4220) ng/L,showing a total difference among them ( F =16.610,P =0.000 ),and the bad protein levels in various dosages of sCD44

  12. 尼莫地平对帕金森病模型鼠黑质多巴胺能神经元中Bcl-2、P53蛋白表达的影响%Effect of Nimodipine on the expression of Bcl-2 and P53 protein in dopaminergic neurons of rats with Parkinson's disease

    Institute of Scientific and Technical Information of China (English)

    费娜; 许丽珍

    2007-01-01

    目的 观察尼莫地平对帕金森病模型鼠多巴胺能神经元中Bcl-2、P53蛋白表达的影响,从而探索尼莫地平对黑质多巴胺能神经元的保护作用.方法 建立大鼠PD模型,分组、分阶段用尼莫地平进行干预,第一阶段为尼莫地平对PD模型的预先干预,第二阶段为成功PD模型的药物治疗(尼莫地平、左旋多巴),其后均由阿朴吗啡(Apomorphine)诱导旋转行为,最后予大鼠黑质细胞进行HE、TH、Bcl-2、P53染色.结果 第一阶段:尼莫地平PD模型组(Ⅰ组)和PD模型组(Ⅱ组),成功模型右侧黑质Bcl-2蛋白表达阳性细胞百分比较假手术组(Ⅲ组)和正常对照组(Ⅳ组)低(P<0.05),而P53蛋白表达阳性细胞百分比较Ⅲ组和Ⅳ组高(P<0.05);Ⅰ组右侧黑质Bcl-2蛋白表达阳性细胞百分比高于Ⅱ组(P<0.05),而P53蛋白表达阳性细胞百分比低于Ⅱ组(P<0.05);第二阶段:尼莫地平组、左旋多巴组或二者联用干预组与生理盐水组间右侧黑质Bcl-2、P53蛋白表达阳性细胞百分比无统计学差异(P>0.05).结论 尼莫地平在蛋白合成水平促进了Bcl-2表达、抑制了P53表达,减缓了多巴胺能神经元的凋亡.

  13. 利妥昔单抗注射液联合CHOP方案治疗弥漫大B细胞淋巴瘤及对bcl-2阳性患者的疗效分析%Efficacy analysis on rituximab combined with CHOP scheme in the treatment of diffuse large B-cell lymphoma and positive expression of bcl-2 protein

    Institute of Scientific and Technical Information of China (English)

    韩艳秋; 任燕珍

    2014-01-01

    目的 探讨利妥昔单抗注射液联合CHOP (R-CHOP)治疗弥漫大B细胞淋巴瘤(DLBCL)及对bcl-2阳性表达患者疗效的影响. 方法 回顾性分析内蒙古医科大学附属医院2009年1月至2013年6月确诊为DLBCL的患者108例,根据化疗方案将其分成CHOP组(45例)和R-CHOP组(63例).对两组患者治疗反应进行比较,采用Log-rank检验法对相关的因素进行单因素分析,采用COX回归模型进行多因素分析,并绘制Kaplan-Meier生存曲线.结果 R-CHOP组的完全缓解情况明显优于CHOP组(x2=7.013,P=0.010),且Kaplan-Meier生存曲线显示R-CHOP组的总生存期较CHOP组明显延长(x2=5.066,P=0.024).单因素及多因素分析显示化疗方案的选择、年龄是否> 60岁、乳酸脱氢酶水平是否达正常值及是否完全缓解是DLBCL的不良预后因素(P均<0.05).DLBCL患者bcl-2阳性表达占56.5%(61/108),其中CHOP组bcl-2阳性表达患者的完全缓解情况明显低于bcl-2阴性表达患者(x2=6.000,P=0.031),且bcl-2阳性表达患者中经R-CHOP治疗后其生存期明显优于CHOP组(x2=4.441,P=0.035). 结论 利妥昔单抗注射液可明显提高DLBCL患者的总生存期,且能够改善bcl-2阳性表达患者的疗效.

  14. Correlation between expression of Bcl-2 protein and cell apoptosis in functioning and non-functioning adrenal tumours%功能性和非功能性肾上腺肿瘤与Bcl-2蛋白表达和细胞凋亡的关系

    Institute of Scientific and Technical Information of China (English)

    杨勇; 徐祗顺; 殷刚

    2006-01-01

    目的 探讨功能性和非功能性肾上腺肿瘤组织中Bcl-2的表达水平和细胞凋亡的关系.方法 运用免疫组织化学染色和TUNEL法检测细胞凋亡情况,探讨4例正常肾上腺(NA)、33例有功能性肾上腺肿瘤(FAT)和23例非功能性肾上腺肿瘤(NFAT)的Bcl-2表达及细胞凋亡情况.结果 Bcl-2阳性细胞的平均百分数在NA、FAT、NFAT分别为(3.8±1.1)%、(6.3±1.2)%、(13.1±1.8)%,其中FAT与NFAT、NA与NFAT比较,均有显著性差异(P<0.05);FAT与NA比较无显著性差异(P>0.05).凋亡的阳性细胞率FAT(1.14±0.30)%高于NFAT的(0.48±0.25)%和NA(0.18±0.05)%,其中FAT与NFAT、FAT与NA、NFAT与NA比较均有显著性差异(P<0.05).Bcl-2的表达与细胞凋亡指数(AI)呈显著负相关(rs=-0.560,P<0.02;rs=-0.530,P<0.03).结论 Bcl-2表达与细胞凋亡抑制关系密切;Bcl-2的表达及细胞凋亡检测对功能性肾上腺肿瘤和非功能性肾上腺肿瘤有一定诊断意义.

  15. Overexpression of Bcl2 in osteoblasts inhibits osteoblast differentiation and induces osteocyte apoptosis.

    Directory of Open Access Journals (Sweden)

    Takeshi Moriishi

    Full Text Available Bcl2 subfamily proteins, including Bcl2 and Bcl-X(L, inhibit apoptosis. As osteoblast apoptosis is in part responsible for osteoporosis in sex steroid deficiency, glucocorticoid excess, and aging, bone loss might be inhibited by the upregulation of Bcl2; however, the effects of Bcl2 overexpression on osteoblast differentiation and bone development and maintenance have not been fully investigated. To investigate these issues, we established two lines of osteoblast-specific BCL2 transgenic mice. In BCL2 transgenic mice, bone volume was increased at 6 weeks of age but not at 10 weeks of age compared with wild-type mice. The numbers of osteoblasts and osteocytes increased, but osteoid thickness and the bone formation rate were reduced in BCL2 transgenic mice with high expression at 10 weeks of age. The number of BrdU-positive cells was increased but that of TUNEL-positive cells was unaltered at 2 and 6 weeks of age. Osteoblast differentiation was inhibited, as shown by reduced Col1a1 and osteocalcin expression. Osteoblast differentiation of calvarial cells from BCL2 transgenic mice also fell in vitro. Overexpression of BCL2 in primary osteoblasts had no effect on osteoclastogenesis in co-culture with bone marrow cells. Unexpectedly, overexpression of BCL2 in osteoblasts eventually caused osteocyte apoptosis. Osteocytes, which had a reduced number of processes, gradually died with apoptotic structural alterations and the expression of apoptosis-related molecules, and dead osteocytes accumulated in cortical bone. These findings indicate that overexpression of BCL2 in osteoblasts inhibits osteoblast differentiation, reduces osteocyte processes, and causes osteocyte apoptosis.

  16. Ekspresi Bcl-2 dan Caspase-3 Pascapaparan Hipoksia Hipobarik Intermiten

    Directory of Open Access Journals (Sweden)

    Achmad Hidayat

    2011-12-01

    Full Text Available Intermittent hypobaric hypoxia often suffered by cabin crew due to the fact that they are breathing lower pressured air inside the plane cabin. Human body will adapt by binding more oxygen and reducing hypoxia effect. Mitochondria function will be irritated by hypoxia which affect, outer mithochondrial membrane permeability due to decrease of Bcl-2 protein. Later on if hypoxia continues mitochondrial membrane will leaked cytocrome-c will released and apoptotic pathway will occur. The purpose of this study was to analyze Bcl-2 protein as antiapoptosis and caspase-3 as apoptosis indicator of intermittent hypobaric hypoxia exposure. Experimental study >was subjected to Spraque Dawley male mice during January–April 2010 by exposing them to several intermittent hypobaric hypoxias (one to four treatment in an interval of one week. Protein expression on mice heart cell were detected by immunohistochemistry in the Department of Pathology Anatomy Padjadjaran University-RS Dr. Hasan Sadikin Bandung and western blot methods in Department Biomolecullar Indonesia University Jakarta. Bcl-2 protein expressions increased according with the frequency of intermittent hypobaric hypoxia exposures while a reverse trend was found for caspase-3 protein expressions (rs=-0.448, p=0.013. From the study it can be concluded that apoptosis will be decreased as a result of intermittent hypobaric hypoxia exposures, which occurred from natural adaptation mechanism indicated by decrease of cell apoptosis and cardio protective effect will be emerged.

  17. Does the expression of BCL2 have prognostic significance in malignant peritoneal mesothelioma?

    OpenAIRE

    Pillai, Krishna; Mohammad H Pourgholami; Chua, Terence C.; Morris, David L.

    2013-01-01

    Background Malignant peritoneal mesothelioma (MPM) is a rare neoplasm of the peritoneal membrane that is causally related to asbestos exposure. Survival after treatment is poor. Current therapy involving hyperthermic intraperitoneal chemotherapy has improved survival in selective patients. In the past, several prognostic factors have been identified in MPM patients and this has prompted the development of new therapies and patient management. Since BCL2, an antiapoptotic oncoprotein, is a fav...

  18. Apoptosis Mediated by HIV Protease is Preceded by Cleavage of Bcl-2

    Science.gov (United States)

    Strack, Peter R.; West Frey, Michelle; Rizzo, Christopher J.; Cordova, Beverly; George, Henry J.; Meade, Raymond; Ho, Siew Peng; Corman, Jeanne; Tritch, Radonna; Korant, Bruce D.

    1996-09-01

    Expression of the human immunodeficiency virus type 1 (HIV) protease in cultured cells leads to apoptosis, preceded by cleavage of bcl-2, a key negative regulator of cell death. In contrast, a high level of bcl-2 protects cells in vitro and in vivo from the viral protease and prevents cell death following HIV infection of human lymphocytes, while reducing the yields of viral structural proteins, infectivity, and tumor necrosis factor α . We present a model for HIV replication in which the viral protease depletes the infected cells of bcl-2, leading to oxidative stress-dependent activation of NFkappa B, a cellular factor required for HIV transcription, and ultimately to cell death. Purified bcl-2 is cleaved by HIV protease between phenylalanine 112 and alanine 113. The results suggest a new option for HIV gene therapy; bcl-2 muteins that have noncleavable alterations surrounding the HIV protease cleavage site.

  19. Comparison of Immunohistochemical Expression of Antiapoptotic Protein Survivin in Normal Oral Mucosa, Oral Leukoplakia, and Oral Squamous Cell Carcinoma

    OpenAIRE

    Amita Negi; Abhiney Puri; Rakhi Gupta; Rajat Nangia; Alisha Sachdeva; Megha Mittal

    2015-01-01

    Background. Oral squamous cell carcinoma is the sixth most frequent malignant tumor worldwide and the third most common cancers in developing countries. Oral leukoplakia is the best-known precursor lesion of oral squamous cell carcinoma. The aim of the present study was to compare immunohistochemical expression of antiapoptotic protein survivin in normal oral mucosa, oral leukoplakia, and oral squamous cell carcinoma. Method. Total 45 specimens of formalin fixed paraffin embedded tissue block...

  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

    Directory of Open Access Journals (Sweden)

    Leda M.F. Lucinda

    2014-06-01

    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. Bcl2 Family Functions as Signaling Target in Nicotine-/NNK-Induced Survival of Human Lung Cancer Cells

    Directory of Open Access Journals (Sweden)

    Xingming Deng

    2014-01-01

    Full Text Available Lung cancer is the leading cause of cancer death and has a strong etiological association with cigarette smoking. Nicotine and nitrosamine 4-(methylnitrosamino-1-(3-pyridyl-1-butanone (NNK are two major components in cigarette smoke that significantly contribute to the development of human lung cancer. Nicotine is able to stimulate survival of both normal human lung epithelial and lung cancer cells. In contrast to nicotine, NNK is a more potent carcinogen that not only induces single-strand DNA breaks and oxidative DNA damage but also stimulates survival and proliferation of normal lung epithelial and lung cancer cells. However, the molecular mechanism(s by which nicotine and NNK promote cell survival, proliferation, and lung tumor development remains elusive. The fate of cells (i.e., survival or death is largely decided by the Bcl2 family members. In the past several years, multiple signaling links between nicotine/NNK and Bcl2 family members have been identified that regulate survival and proliferation. This review provides a concise, systematic overview of the current understanding of the role of the pro- or antiapoptotic proteins in cigarette smoking, lung cancer development, and treatment resistance.

  2. Apoptosis regulatory protein,survivin,expression and relationship with bcl-2 protien in pituitary adenoma%Survivin凋亡抑制基因在垂体腺瘤中的表达及其与bcl-2、p53相关性的研究

    Institute of Scientific and Technical Information of China (English)

    马杰; 魏冰; 乔思杰

    2002-01-01

    目的: 探讨凋亡抑制基因survivin在垂体腺瘤中的表达,及其与bcl-2和p53表达蛋白的相关性.方法: 采用免疫组织化学链霉菌抗生物素蛋白-过氧化酶连接法(SP法),检测survivin、bcl-2、p53基因表达蛋白在8例正常垂体组织及38例垂体腺瘤组织中的表达.结果: survivin基因表达蛋白在正常垂体中无表达,38例垂体腺瘤中,23例表达阳性,占60.5%病理分型中PRL型、GH型、混合型阳性表达率分别为12/17、7/13、4/8三者比较,差异无显著性(P>0.05).垂体腺瘤bcl-2表达蛋白的阳性与阴性中,survivin蛋白表达阳性率分别为15/17、8/21.两者比较,差异有显著性(P<0.05):而p53表达蛋白的阳性和阴性中,survivin蛋白表达阳性率分别为2/6,22/23,两者相比,差异无显著性(P>0.05):survivin基因蛋白的表达阳性率与垂体腺瘤组织中的bcl-2蛋白表达密切相关,与p53蛋白表达无相关性.结论: survivin蛋白表达的异常而引起细胞凋亡抑制,在垂体腺瘤的发生中起一定作用,其过度表达提示垂体腺瘤增生极度活跃,survivin蛋白表达与垂体腺瘤中bcl-2蛋白的异常表达密切相关.

  3. Bcl-2, Bcl-xL, and p-AKT are involved in neuroprotective effects of transcription factor Brn3b in an ocular hypertension rat model of glaucoma

    Science.gov (United States)

    Phatak, Nitasha R.; Stankowska, Dorota L.

    2016-01-01

    Purpose Brn3b is a class IV POU domain transcription factor that plays an important role in the development of retinal ganglion cells (RGCs), RGC survival, and particularly axon growth and pathfinding. Our previous study demonstrated that recombinant adenoassociated virus serotype 2 (rAAV-2)–mediated overexpression of Brn3b in RGCs promoted neuroprotection in a rodent model of glaucoma. However, the mechanisms underlying neuroprotection of RGCs in rats overexpressing Brn3b in animal models of glaucoma remain largely unknown. The goal of this study was to understand some of the mechanisms underlying the neuroprotection of RGCs overexpressing Brn3b during intraocular pressure (IOP) elevation in Brown Norway rats. Methods One eye of Brown Norway rats (Rattus norvegicus) was injected with an AAV construct encoding either green fluorescent protein (GFP; recombinant adenoassociated virus–green fluorescent protein, rAAV-hSyn-GFP) or Brn3b (rAAV-hSyn-Brn3b). Expression of antiapoptotic proteins, including B cell lymphoma/leukemia-2 (Bcl-2) family proteins (Bcl-2 and Bcl-xL), and p-AKT, was observed following immunostaining of rat retinas that overexpress Brn3b. In a different set of experiments, intraocular pressure was elevated in one eye of Brown Norway rats, which was followed by intravitreal injection with AAV constructs encoding either GFP (rAAV-CMV-GFP) or Brn3b (rAAV-CMV-Brn3b). Retinal sections were stained for prosurvival factors, including Bcl-2, Bcl-XL, and p-AKT. Results AAV-mediated expression of transcription factor Brn3b promoted statistically significant upregulation of the Bcl-2 protein and increased expression of p-AKT in RGCs of Brown Norway rats. In addition, following IOP elevation, AAV-mediated Brn3b expression also statistically significantly increased levels of Bcl-2 in the RGC layer in Brown Norway rats. Conclusions Adenoassociated virus–mediated Brn3b protein overexpression may promote neuroprotection by upregulating key antiapoptotic

  4. 8周中等强度低负荷量训练对老龄雌性大鼠骨骼肌Bax和Bcl-2蛋白及SIRT1/SIRT3信号轴基因表达的影响%Effects of 8-week medium intensity low load training on proteins Bax and Bcl-2 and the gene expression of signal axis SIRT1/SIRT3 of skeletal muscle of aged female rats

    Institute of Scientific and Technical Information of China (English)

    李方晖; 肖琳; 覃飞; 刘承宜

    2014-01-01

    In order to observe the effects of 8-week medium intensity low load training on the levels of proteins Bax and Bcl-2 and the gene messenger RNA (mRNA) expression of axis sirtuin 1 (SIRT1)/sirtuin 3 (SIRT3) of gastrocne-mius of aged rats, the authors divided 16 18-month old female SD rats randomly into a control group and an exercise group, each of which contained 8 rats, let the rats in the exercise group do an aerobic exercise on a treadmill for con-secutive 8 weeks, at a speed of 15 km/h (with 60%~75%VO2max), 15 minutes a day, 5 days a week, let the rats in the control group live freely, in 24 hours after rat exercising at the end of week 8, killed the rats, measured gastrocnemius index, measured the levels of proteins Bax and Bcl-2 of gastrocnemius by means of Western blot analysis, measured the mRNA levels of SIRT3, SIRT1, manganese superoxide dismutase (MnSOD), Caspase 3, peroxisome prolifera-tor-activated receptor-γcoactivator-1 (PGC-1α), mitochondrial transcription factor A (TFAM) and nuclear respiratory factor 1 (NRF1) by means of RT-PCR, and revealed the following findings:as for the rats in the exercise group, their gastrocnemius mass and gastrocnemius index increased significantly (P<0.05 and P<0.01 respectively), their protein Bax level decreased significantly (P<0.05), their protein Bcl-2 level and Bcl-2/Bax ratio increased significantly (P<0.05);their mRNA levels of SIRT3, SIRT1, PGC-1α, NRF1, TFAM and MnSOD increased significantly (P<0.05), their mRNA level of Caspase-3 decreased significantly (P<0.05). The said findings indicated the followings:medium intensity low load training could delay the changing of muscle cell apoptosis signal of aged rats; the homeostatic mechanism mediated by axis SIRT1/SIRT3 played an important role in medium intensity low load training increasing the mitochondria refreshing rate and antioxidase level of skeletal muscle of aged rats.%观察8周中等强度低负荷量训练对老龄雌性大鼠腓肠肌Bax和Bcl-2

  5. Targeting BCL-2 to enhance vulnerability to therapy in estrogen receptor-positive breast cancer.

    Science.gov (United States)

    Merino, D; Lok, S W; Visvader, J E; Lindeman, G J

    2016-04-14

    The last three decades have seen significant progress in our understanding of the role of the pro-survival protein BCL-2 and its family members in apoptosis and cancer. BCL-2 and other pro-survival family members including Mcl-1 and BCL-XL have been shown to have a key role in keeping pro-apoptotic 'effector' proteins BAK and BAX in check. They also neutralize a group of 'sensor' proteins (such as BIM), which are triggered by cytotoxic stimuli such as chemotherapy. BCL-2 proteins therefore have a central role as guardians against apoptosis, helping cancer cells to evade cell death. More recently, an increasing number of BH3 mimetics, which bind and neutralize BCL-2 and/or its pro-survival relatives, have been developed. The utility of targeting BCL-2 in hematological malignancies has become evident in early-phase studies, with remarkable clinical responses seen in heavily pretreated patients. As BCL-2 is overexpressed in ~75% of breast cancer, there has been growing interest in determining whether this new class of drug could show similar promise in breast cancer. This review summarizes our current understanding of the role of BCL-2 and its family members in mammary gland development and breast cancer, recent progress in the development of new BH3 mimetics as well as their potential for targeting estrogen receptor-positive breast cancer.

  6. Ekspresi Bcl-2 dan Caspase-3 Pascapaparan Hipoksia Hipobarik Intermiten

    OpenAIRE

    Achmad Hidayat; Kahdar Wiradisastra; Bethy S. Hernowo; Tri Hanggono Achmad

    2011-01-01

    Intermittent hypobaric hypoxia often suffered by cabin crew due to the fact that they are breathing lower pressured air inside the plane cabin. Human body will adapt by binding more oxygen and reducing hypoxia effect. Mitochondria function will be irritated by hypoxia which affect, outer mithochondrial membrane permeability due to decrease of Bcl-2 protein. Later on if hypoxia continues mitochondrial membrane will leaked cytocrome-c will released and apoptotic pathway will occur. The purpose ...

  7. 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...... expression might impair tumor growth and survival, this protein may serve as a rational target for vaccine-induced CTL responses. By Western blot technique, we screened a panel of established human tumor cell lines for proteins involved in the apoptotic process. Two of eight tumor cell lines, a B lymphoma...... (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...

  8. Fish oil administration mediates apoptosis of Walker 256 tumor cells by modulation of p53, Bcl-2, caspase-7 and caspase-3 protein expression

    OpenAIRE

    Borghetti, Gina; Yamaguchi, Adriana Aya; Aikawa, Julia; Yamazaki, Ricardo Key; de Brito, Gleisson Alisson Pereira; Fernandes, Luiz Claudio

    2015-01-01

    Background Several studies have been shown pro-apoptotic effects of fish oil (FO), rich in n-3 polyunsaturated fatty acids (n-3 PUFA) on cancer cells. Nevertheless, few in vivo experiments have provided data of its ability on apoptosis protein expression in tumor tissue. Thus, in this study we investigate the effect of FO supplementation on apoptosis protein expression in Walker 256 tumor bearing rats. Male Wistar rats were randomly assigned to three groups: fed with regular chow (W); fed reg...

  9. Ectopic expression of clusterin/apolipoprotein J or Bcl-2 decreases the sensitivity of HaCaT cells to toxic effects of ropivacaine

    Institute of Scientific and Technical Information of China (English)

    2004-01-01

    Local anesthetics inhibit cell proliferation and induce apoptosis in various cell types. Ropivacaine, a unique, novel tertiary amine-type anesthetic, was shown to inhibit the proliferation of several cell types including keratinocytes. We found that Ropivacaine could inhibit the proliferation and induce apoptosis in an immortalized human keratinocyte line,HaCaT, in a dose- and time-dependent manner and with the deprivation of serum. The dose-dependent induction of apoptosis by ropivacaine was demonstrated by DNA fragmentation analysis and the proteolytic cleavage of a caspase-3substrate - poly (ADP-ribose) polymerase (PARP). In addition, ropivacaine downregulated the expression of clusterin/apoliporotein J, a protein with anti-apoptotic properties, in a dose-dependent manner, which well correlated with the induction of apoptosis of HaCaT cells. To investigate the role of clusterin/apoliporotein J in ropivacaine-induced apoptosis,HaCaT cells overexpressing clusterin/apoliporotein J were generated and compared to cells expressing the well established anti-apoptotic Bcl-2 protein. Ectopic overexpression of the secreted form of clusterin/apoliporotein J or Bcl-2decreased the sensitivity of HaCaT cells to toxic effects of ropivacaine as demonstrated by DNA fragmentation, the proteolytic cleavage of PARP and by a reduction in procaspase-3 expression. Furthermore, the downregulation of endogenous clusterin/apolipoprotein J levels by ropivacaine suggested that this might be one mechanism by which ropivacaine induced cell death in HaCaT cells. In conclusion, the ability of ropivacaine to induce antiproliferative responses and to suppress the expression of the anti-apoptotic protein clusterin/apolipoprotein J, combined with previously reported anti-inflammatory activity and analgesic property of the drug, suggests that ropivacaine may have potential utility in the local treatment of tumors.

  10. The orphan adapter protein SLY1 as a novel anti-apoptotic protein required for thymocyte development

    Directory of Open Access Journals (Sweden)

    Beer-Hammer Sandra

    2009-07-01

    Full Text Available Abstract Background SH3 containing Lymphocyte Protein (SLY1 is a putative adapter protein exclusively expressed in lymphocytes which is involved in antigen receptor induced activation. We previously have generated SLY1Δ/Δ mice harbouring a partial deletion in the N-terminal region of SLY1 which revealed profound immunological defects in T and B cell functions. Results In this study, T cell development in SLY1-/- and SLY1Δ/Δ mice was analysed ex vivo and upon cultivation with the bone marrow stromal cell line OP9. SLY1-deficient thymocytes were compromised in inducing nutrient receptor expression and ribosomal protein S6 phosphorylation, indicating a defect in mTOR complex activation. Furthermore, SLY1 was identified as a novel anti-apoptotic protein required for developmental progression of T cell precursors to the CD4+CD8+ double-positive stage by protecting from premature programmed cell death initiation in developing CD4-CD8- double-negative thymocytes. In addition, SLY1 phosphorylation was differentially regulated upon Notch ligand-mediated stimulation and expression of the preTCR. Conclusion Thus, our results suggest a non-redundant role for SLY1 in integrating signals from both receptors in early T cell progenitors in the thymus.

  11. Targeting the Anti-Apoptotic Protein c-FLIP for Cancer Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Safa, Ahmad R., E-mail: asafa@iupui.edu [Department of Pharmacology and Toxicology, Indiana University School of Medicine, 980 W. Walnut Street, R3-C524, Indianapolis, IN 46202 (United States); Indiana University Simon Cancer Center, Indiana University School of Medicine, 980 W. Walnut Street, R3-C524, Indianapolis, IN 46202 (United States); Pollok, Karen E. [Department of Pharmacology and Toxicology, Indiana University School of Medicine, 980 W. Walnut Street, R3-C524, Indianapolis, IN 46202 (United States); Indiana University Simon Cancer Center, Indiana University School of Medicine, 980 W. Walnut Street, R3-C524, Indianapolis, IN 46202 (United States); Herman B. Wells Center for Pediatric Research, 980 W. Walnut Street, R3-C524, Indianapolis, IN 46202 (United States)

    2011-03-29

    Cellular FLICE (FADD-like IL-1beta-converting enzyme)-inhibitory protein (c-FLIP) is a major resistance factor and critical anti-apoptotic regulator that inhibits tumor necrosis factor-alpha (TNF-alpha), Fas-L, and TNF-related apoptosis-inducing ligand (TRAIL)-induced apoptosis as well as chemotherapy-triggered apoptosis in malignant cells. c-FLIP is expressed as long (c-FLIP{sub L}), short (c-FLIP{sub S}), and c-FLIP{sub R} splice variants in human cells. c-FLIP binds to FADD and/or caspase-8 or -10 in a ligand-dependent and-independent fashion, which in turn prevents death-inducing signaling complex (DISC) formation and subsequent activation of the caspase cascade. Moreover, c-FLIP{sub L} and c-FLIP{sub S} are known to have multifunctional roles in various signaling pathways, as well as activating and/or upregulating several cytoprotective signaling molecules. Upregulation of c-FLIP has been found in various tumor types, and its downregulation has been shown to restore apoptosis triggered by cytokines and various chemotherapeutic agents. Hence, c-FLIP is an important target for cancer therapy. For example, small interfering RNAs (siRNAs) that specifically knockdown the expression of c-FLIP{sub L} in diverse human cancer cell lines augmented TRAIL-induced DISC recruitment and increased the efficacy of chemotherapeutic agents, thereby enhancing effector caspase stimulation and apoptosis. Moreover, small molecules causing degradation of c-FLIP as well as decreasing mRNA and protein levels of c-FLIP{sub L} and c-FLIP{sub S} splice variants have been found, and efforts are underway to develop other c-FLIP-targeted cancer therapies. This review focuses on (1) the functional role of c-FLIP splice variants in preventing apoptosis and inducing cytokine and drug resistance; (2) the molecular mechanisms that regulate c-FLIP expression; and (3) strategies to inhibit c-FLIP expression and function.

  12. Effects of Exercise Pre-Conditioning on Hippocampus Expression of Bcl-2 and Bax Protein and Apoptosis Following Ischemia/Reperfusion Injury in Male Rats

    OpenAIRE

    Nabi Shamsaei; Hamid Rajabi; Nahid Aboutaleb; Farnaz Nikbakht; Pezhman Motamedi; Mehdi Khaksari; Sohaila Erfani

    2015-01-01

    Introduction: Cerebral ischemia/reperfusion leads to loss of vulnerable neurons by apoptosis in specific brain regions specially in the hippocampus. There is some evidence indicating that the neuroprotective effects of physical activity on the brain. Therefore,the main purpose of this study was to investigate the effect of exercise pre-conditioning on apoptosis-related proteins expression in hippocampal CA1 neurons after induction of ischemia. Methods: 21 Male rats weighing 260-300g were ...

  13. Carboxypeptidase E Protects Hippocampal Neurons During Stress in Male Mice by Up-regulating Pro-survival BCL2 Protein Expression

    OpenAIRE

    Murthy, S. R. K.; Thouennon, E.; Li, W.-S.; Cheng, Y; Bhupatkar, J.; Cawley, N.X.; Lane, M.; Merchenthaler, I; Loh, Y P

    2013-01-01

    Prolonged chronic stress causing elevated plasma glucocorticoids leads to neurodegeneration. Adaptation to stress (allostasis) through neuroprotective mechanisms can delay this process. Studies on hippocampal neurons have identified carboxypeptidase E (CPE) as a novel neuroprotective protein that acts extracellularly, independent of its enzymatic activity, although the mechanism of action is unclear. Here, we aim to determine if CPE plays a neuroprotective role in allostasis in mouse hippocam...

  14. The N-terminus and alpha-5, alpha-6 helices of the pro-apoptotic protein Bax, modulate functional interactions with the anti-apoptotic protein Bcl-xL

    Directory of Open Access Journals (Sweden)

    Sowdhamini R

    2007-05-01

    Full Text Available Abstract Background Bcl-2 family proteins are key regulators of mitochondrial integrity and comprise both pro- and anti-apoptotic proteins. Bax a pro-apoptotic member localizes as monomers in the cytosol of healthy cells and accumulates as oligomers in mitochondria of apoptotic cells. The Bcl-2 homology-3 (BH3 domain regulates interactions within the family, but regions other than BH3 are also critical for Bax function. Thus, the N-terminus has been variously implicated in targeting to mitochondria, interactions with BH3-only proteins as well as conformational changes linked to Bax activation. The transmembrane (TM domains (α5-α6 helices in the core and α9 helix in the C-terminus in Bax are implicated in localization to mitochondria and triggering cytotoxicity. Here we have investigated N-terminus modulation of TM function in the context of regulation by the anti-apoptotic protein Bcl-xL. Results Deletion of 29 amino acids in the Bax N-terminus (Bax 30–192 caused constitutive accumulation at mitochondria and triggered high levels of cytotoxicity, not inhibited by Bcl-xL. Removal of the TM domains (Bax 30–105 abrogated mitochondrial localization but resulted in Bcl-xL regulated activation of endogenous Bax and Bax-Bak dependent apoptosis. Inclusion of the α5-α6 helices/TMI domain (Bax 30–146 phenocopied Bax 30–192 as it restored mitochondrial localization, Bcl-xL independent cytotoxicity and was not dependent on endogenous Bax-Bak. Inhibition of function and localization by Bcl-xL was restored in Bax 1–146, which included the TM1 domain. Regardless of regulation by Bcl-xL, all N-terminal deleted constructs immunoprecipitated Bcl-xLand converged on caspase-9 dependent apoptosis consistent with mitochondrial involvement in the apoptotic cascade. Sub-optimal sequence alignments of Bax and Bcl-xL indicated a sequence similarity between the α5–α6 helices of Bax and Bcl-xL. Alanine substitutions of three residues (T14A-S15A-S16A in

  15. Expression of Bcl-2 in adult human brain regions with special reference to neurodegenerative disorders.

    Science.gov (United States)

    Vyas, S; Javoy-Agid, F; Herrero, M T; Strada, O; Boissiere, F; Hibner, U; Agid, Y

    1997-07-01

    The expression of the protooncogene bcl-2, an inhibitor of apoptosis in various cells, was examined in the adult human brain. Several experimental criteria were used to verify its presence; mRNA was analyzed by northern blot with parallel experiments in mouse tissues, by RNase protection, and by in situ hybridization histochemistry. Bcl-2 protein was detected by western blot analysis and immunohistochemistry. Two bcl-2 mRNA species were identified in the human brain. The pattern of distribution of bcl-2 mRNA at the cellular level showed labeling in neurons but not glia. The in situ hybridization signal was stronger in the pyramidal neurons of the cerebral cortex and in the cholinergic neurons of the nucleus basalis of Meynert than in the Purkinje neurons of the cerebellum. Both melanized and nonmelanized neurons were labeled in the substantia nigra. In the striatum, bcl-2 mRNA was detected in some but not all neurons. In the regions examined for Bcl-2 protein, the expression pattern correlated with the mRNA results. In patients with Alzheimer's and Parkinson's diseases, quantification of bcl-2 mRNA in the nucleus basalis of Meynert and substantia nigra, respectively, showed that the expression was unaltered compared with controls, raising the possibility that the expression of other components of apoptosis is modulated.

  16. Expression of bax、bcl-2、CD44v6、nm23 protein in transitional cell carcinoma of the bladder%膀胱移行细胞癌中bax、bcl-2、CD44v6、nm23表达

    Institute of Scientific and Technical Information of China (English)

    张玉华; 陈萍; 朴颖实; 韩影; 李弘; 张伟东; 刘宪军; 巩雷; 谢江

    2004-01-01

    目的探讨bax、bcl-2、CD44、nm23基因蛋白在膀胱移行细胞癌(TCC)中的表达.方法应用免疫组化S-P法对64例膀胱TCC及20例正常膀胱黏膜组织中bax、bcl-2、CD44v6、nm23进行检测.结果 64例膀胱TCC中bax阳性率为17.2%(11/64),正常膀胱黏膜组织为90.0%(18/20)(P《0.05). 膀胱TCC中bcl-2阳性表达率为82.8%(53/64),正常膀胱黏膜为20.0%(4/20)(P《0.05).bax 、bcl-2阳性率随组织学分级的提高有逐渐增强的趋势,但无统计学意义(P》0.05);在无浸润及有深层浸润的膀胱TCC中,bax的阳性表达率分别为16.3%、20.0%(P》0.05),bcl-2则分别为83.7%、80.0%(P》0.05);在无复发转移及有复发转移的膀胱TCC中,bax阳性率分别为16.1%、25.0%(P》0.05),bcl-2分别为82.1%、87.5%(P》0.05).64例膀胱TCC中CD44v6阳性表达率为50.0%(32/64),正常膀胱黏膜组织为5.0%(1/20)(P《0.05).nm23在膀胱TCC中的阳性率为76.6%(49/64),正常膀胱黏膜组织为20.0%(4/20)(P《0.05).CD44v6阳性率Ⅰ、Ⅱ级与Ⅲ级相比差异有显著性(P《0.05),nm23阳性率Ⅰ级与Ⅱ、Ⅲ级相比差异有显著性(P《0.05);在有深层浸润的膀胱TCC中CD44v6、nm 23阳性表达率均明显高于无浸润的病例(P《0.05);有复发转移的膀胱TCC CD44v6阳性率高于无复发转移的病例(P《0.05),而nm23在膀胱TCC中的阳性表达率与有无复发转移无明显相关性(P》0.05).结论 bax表达水平下降及bcl-2的表达增强在膀胱TCC的发生中起到重要作用,CD44v6、nm23也参与促进了膀胱TCC的发生.bax、bcl-2与肿瘤的组织学分级、浸润深度、复发、转移等无关,但CD44v6与之呈正相关.nm23与组织学分级、浸润深度呈正相关,而与复发或转移无相关性.

  17. Antisense bcl-2 treatment increases programmed cell death in non-small cell lung cancer cell lines.

    Science.gov (United States)

    Koty, P P; Zhang, H; Levitt, M L

    1999-02-01

    Programmed cell death (PCD) is a genetically regulated pathway that is altered in many cancers. This process is, in part, regulated by the ratio of PCD inducers (Bax) or inhibitors (Bcl-2). An abnormally high ratio of Bcl-2 to Bax prevents PCD, thus contributing to resistance to chemotherapeutic agents, many of which are capable of inducing PCD. Non-small cell lung cancer (NSCLC) cells demonstrate resistance to these PCD-inducing agents. If Bcl-2 prevents NSCLC cells from entering the PCD pathway, then reducing the amount of endogenous Bcl-2 product may allow these cells to spontaneously enter the PCD pathway. Our purpose was to determine the effects of bcl-2 antisense treatment on the levels of programmed cell death in NSCLC cells. First, we determined whether bcl-2 and bax mRNA were expressed in three morphologically distinct NSCLC cell lines: NCI-H226 (squamous), NCI-H358 (adenocarcinoma), and NCI-H596 (adenosquamous). Cells were then exposed to synthetic antisense bcl-2 oligonucleotide treatment, after which programmed cell death was determined, as evidenced by DNA fragmentation. Bcl-2 protein expression was detected immunohistochemically. All three NSCLC cell lines expressed both bcl-2 and bax mRNA and had functional PCD pathways. Synthetic antisense bcl-2 oligonucleotide treatment resulted in decreased Bcl-2 levels, reduced cell proliferation, decreased cell viability, and increased levels of spontaneous PCD. This represents the first evidence that decreasing Bcl-2 in three morphologically distinct NSCLC cell lines allows the cells to spontaneously enter a PCD pathway. It also indicates the potential therapeutic use of antisense bcl-2 in the treatment of NSCLC. PMID:10217615

  18. Phosphorylation of Puma modulates its apoptotic function by regulating protein stability

    OpenAIRE

    Fricker, M; O'Prey, J.; Tolkovsky, A M; Ryan, K M

    2010-01-01

    Puma is a potent BH3-only protein that antagonises anti-apoptotic Bcl-2 proteins, promotes Bax/Bak activation and has an essential role in multiple apoptotic models. Puma expression is normally kept very low, but can be induced by several transcription factors including p53, p73, E2F1 and FOXO3a, whereby it can induce an apoptotic response. As Puma can to bind and inactivate all anti-apoptotic members of the Bcl-2 family, its activity must be tightly controlled. We report here, for the first ...

  19. Involvement of PI3K and MAPK Signaling in bcl-2-induced Vascular Endothelial Growth Factor Expression in Melanoma Cells

    Science.gov (United States)

    Trisciuoglio, Daniela; Iervolino, Angela; Zupi, Gabriella; Del Bufalo, Donatella

    2005-01-01

    We have previously demonstrated that bcl-2 overexpression in tumor cells exposed to hypoxia increases the expression of vascular endothelial growth factor (VEGF) gene through the hypoxia-inducible factor-1 (HIF-1). In this article, we demonstrate that exposure of bcl-2 overexpressing melanoma cells to hypoxia induced phosphorylation of AKT and extracellular signal-regulated kinase (ERK)1/2 proteins. On the contrary, no modulation of these pathways by bcl-2 was observed under normoxic conditions. When HIF-1α expression was reduced by RNA interference, AKT and ERK1/2 phosphorylation were still induced by bcl-2. Pharmacological inhibition of mitogen-activated protein kinase (MAPK) and phosphatidylinositol 3-kinase (PI3K) signaling pathways reduced the induction of VEGF and HIF-1 in response to bcl-2 overexpression in hypoxia. No differences were observed between control and bcl-2-overexpressing cells in normoxia, in terms of VEGF protein secretion and in response to PI3K and MAPK inhibitors. We also demonstrated that RNA interference-mediated down-regulation of bcl-2 expression resulted in a decrease in the ERK1/2 phosphorylation and VEGF secretion only in bcl-2-overexpressing cell exposed to hypoxia but not in control cells. In conclusion, our results indicate, for the first time, that bcl-2 synergizes with hypoxia to promote expression of angiogenesis factors in melanoma cells through both PI3K- and MAPK-dependent pathways. PMID:15987743

  20. Curcumin significantly enhances dual PI3K/Akt and mTOR inhibitor NVP-BEZ235-induced apoptosis in human renal carcinoma Caki cells through down-regulation of p53-dependent Bcl-2 expression and inhibition of Mcl-1 protein stability.

    Directory of Open Access Journals (Sweden)

    Bo Ram Seo

    Full Text Available The PI3K/Akt and mTOR signaling pathways are important for cell survival and growth, and they are highly activated in cancer cells compared with normal cells. Therefore, these signaling pathways are targets for inducing cancer cell death. The dual PI3K/Akt and mTOR inhibitor NVP-BEZ235 completely inhibited both signaling pathways. However, NVP-BEZ235 had no effect on cell death in human renal carcinoma Caki cells. We tested whether combined treatment with natural compounds and NVP-BEZ235 could induce cell death. Among several chemopreventive agents, curcumin, a natural biologically active compound that is extracted from the rhizomes of Curcuma species, markedly induced apoptosis in NVP-BEZ235-treated cells. Co-treatment with curcumin and NVP-BEZ235 led to the down-regulation of Mcl-1 protein expression but not mRNA expression. Ectopic expression of Mcl-1 completely inhibited curcumin plus NVP-NEZ235-induced apoptosis. Furthermore, the down-regulation of Bcl-2 was involved in curcumin plus NVP-BEZ235-induced apoptosis. Curcumin or NVP-BEZ235 alone did not change Bcl-2 mRNA or protein expression, but co-treatment reduced Bcl-2 mRNA and protein expression. Combined treatment with NVP-BEZ235 and curcumin reduced Bcl-2 expression in wild-type p53 HCT116 human colon carcinoma cells but not p53-null HCT116 cells. Moreover, Bcl-2 expression was completely reversed by treatment with pifithrin-α, a p53-specific inhibitor. Ectopic expression of Bcl-2 also inhibited apoptosis in NVP-BE235 plus curcumin-treated cells. In contrast, NVP-BEZ235 combined with curcumin did not have a synergistic effect on normal human skin fibroblasts and normal human mesangial cells. Taken together, combined treatment with NVP-BEZ235 and curcumin induces apoptosis through p53-dependent Bcl-2 mRNA down-regulation at the transcriptional level and Mcl-1 protein down-regulation at the post-transcriptional level.

  1. Suppression of bcl-2 Gene by RNA Interference Increases Chemosensitivity to Cisplatin in Nasopharyngeal Carcinoma Cell Line CNE1

    Institute of Scientific and Technical Information of China (English)

    Zhi-Hua YIN; Cai-Ping REN; Feng LI; Xu-Yu YANG; Hui LI; Ming ZHAO; Kai-Tai YAO

    2004-01-01

    To explore the effect of suppressing BCL-2 expression using RNA interference (RNAi) technique in nasopharyngeal carcinoma cell line CNE1. CNE1 cell lines stably expressing shRNAs targeted bcl-2 and GL3 gene were established and gene expression inhibition was assessed by Western blotting analysis. The effect of suppressing bcl-2 by RNAi on cell growth was studied, the apoptosis induction and the sensitization of CNE 1 cells to cisplatin were quantified by MTT assay and flow cytometry. The results showed that: stable transfection of CNE 1 cells with vectors expressing shRNAs against bcl-2 decreased the expression of BCL-2 protein; suppression of BCL-2 expression did not affect cell proliferation but could increase the chemosensitivity to cisplatin in CNE1 cells. This will help physicians to make some clinical trials of gene therapy on nasopharyngeal carcinoma by RNAi.

  2. Progress in BCL2 inhibition for patients with chronic lymphocytic leukemia.

    Science.gov (United States)

    Tam, Constantine S; Seymour, John F; Roberts, Andrew W

    2016-04-01

    The prosurvival protein BCL2 is uniformly expressed in chronic lymphocytic leukemia (CLL), and enables leukemia cell survival in the face of cytotoxic treatment and increasing genomic, metabolic, and oxidative stresses. The therapeutic potential of BCL2 inhibition was first observed in the clinic following BCL2 antisense therapy. Subsequently, a number of small molecule inhibitors were developed to mimic the function of the pro-apoptotic BH3-only proteins (BH3-mimetics). These molecules are now in late-phase clinical trials and demonstrate potent activity, including the occurrence of acute tumor lysis syndrome in subjects with multiply relapsed, chemorefractory CLL. In this review, we discuss the history and summarize current knowledge regarding BCL2 inhibition as therapy of CLL. PMID:27040706

  3. Studies of Liposomal bcl-2 Antisense Oligode-oxynucleofide Induction of Apoptosis in Raji Cells

    Institute of Scientific and Technical Information of China (English)

    DongmeiHe; HuanZhong

    2004-01-01

    OBJECTIVE To explore the effect of liposomal G3139 and transfected antisense phosphorothioate oligodeoxynucleotides directed against the coding region of the bcl-2 messenger RNA and the translation site on apoptosis in Raji cells.METHODS Cytotoxic effects were measured by use of the MTT method; The expression levels of Bcl-2 protein were assayed by immunofiuorescence using a fluoresce isothiocyanate label. Apoptosis was determined by morphological observation and flow cytometric analysis.RESULTS The 2 antisense oligonucleotides and G3139 can reduce Bcl-2 protein levels and Raji cell viability (IC50=4.54, 4.72 and 4.26 μmol/L, respectively), and induce apoptosis. A scrambled sequence control oligonucleotide and empty liposomes did not alter cell viability, Bcl-2 protein expression or apoptosis rates. There was no difference in reducing Bcl-2 protein levels and apoptosis rates found among the 3 antisense oligonucleotides.CONCLUSION The 2 antisense oligodeoxynucleotides of bcl-2 messenger RNA can effectively induce apoptosis of Raji cells. The 2 antisense sequences and G3139 have a similarity in their antisense effect.

  4. 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.

  5. THE EXPRESSION AND CLINICAL VALUE OF APOPTOSIS CONTROL GENE Bcl-2 AND Bax IN BREAST CANCER

    Institute of Scientific and Technical Information of China (English)

    ZHENG Jun; YAO Zhen-xiang; ZHANG Jing

    1999-01-01

    Objective: To study the expression and clinical value of apoptosis control gene bcl-2 and bax in breast cancer.Methods: Protein bax and bcl-2 in 41 breast cancers obtained from operations in our hospital in 1996 were detected using ABC immunohistochemical stain assay and compared with 10 cases with normal breast tissues.Results: The positive rate of bax in normal breast tissue was 90% and in breast cancer was 59%, with a significant statistical difference between them (P<0.05), but there was no statistical difference in bcl-2 protein expression. Among the 41 breast cancer, the group with lymph node metastasis (21 cases) had obviously low bax expression (43%) and high bcl-2 expression (76%), showing significant difference to the group without lymph node metastasis (P<0.05).Conclusion: The antiapoptosis function of bcl-2 was stronger than bax in breast cancer. Protein bax and bcl-2 assay may be useful in understanding the biological behaviors of breast cancer.

  6. Utility of adenovirus-mediated Fas ligand and bcl-2 gene transfer to modulate rat liver allograft survival

    Institute of Scientific and Technical Information of China (English)

    De-Sheng Wang; Yu Li; Ke-Feng Dou; Kai-Zong Li; Zhen-Shun Song

    2006-01-01

    BACKGROUND: Expression of Fas ligand (FasL) on the graft by gene transduction is expected to introduce apoptosis to lymphocytes to protect rejection, but the FasL-expressing graft cells may also induce apoptosis as the graft usually expresses Fas antigens. In this study, a strong antiapoptotic gene, bcl-2, was cotransfected with the FasL gene in rat liver graft to protect against Fas-mediated cell death and to prolong recipient survival. METHODS: Orthotopic liver transplantation was done in a strain combination of DA to LEW rats. After donor vascular isolation, adenovirus-mediated FasL and bcl-2 genes were cotransfected in the liver graft. RESULTS: Intragraft expression of FasL mRNA was constitutively expressed after adenovirus-mediated transduction, although expression of FasL increased mildly in control grafts. Bcl-2 mRNA was highly expressed at 2 days after reperfusion. In contrast, lower expression of bcl-2 was observed in the control group. The average survival of the gene transferred allografts increased from (9.8+1.3) days to (18.5+8.7) days compared with the control group. CONCLUSION: Our results indicate that rat liver allografts can be protected against host immune responses by adenovirus-mediated FasL and bcl-2 transfection, and that bcl-2 expression prevents the graft from Fas-mediated apoptosis.

  7. Expression of Bcl-2 in cells with different telomerase activities

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Both telomerase and Bcl-2 are important genes in controlling apoptosis. The activation of telomerase and the abnormal regulation of Bcl-2 are also closely related to carcinogenesis. However, little is known about the linkage between telomerase and Bcl-2. The effect of activated telomerase on the expression of Bcl-2 has been investigated. It is demonstrated that in tumor and transformed cells with higher telomerase activity, Bcl-2 expression is significantly lower than that in telomerase negative or less telomerose activity cells. Further study showed that in the telomerase gene-transformed 2BS-fibroblasts, Bcl-2 expression is inhibited significantly while the exogenous telomerase catalytic subunit gene is re-expressed in fibroblasts. Results indicated that there might be a certain linkage between the expression of telomerase and Bcl-2, and overexpression of exogenous telomerase gene might down regulate the expression of Bcl-2.

  8. Prognostic significance of bcl-2 and p53 expression in colorectal carcinoma

    Institute of Scientific and Technical Information of China (English)

    ZHAO Dan-ping; DING Xiao-wen; PENG Jia-ping; ZHENG Yi-xiong; ZHANG Su-zhan

    2005-01-01

    Objective: This study was designed to detect the expression ofbcl-2 and p53 proteins in colorectal carcinomas and to determine their association with the patient survival and stage of the diseases. Methods: Immunohistochemistry method was used to detect the expression ofbcl-2 and p53 proteins in 93 cases of colorectal carcinoma. The stain results were obtained by analyzing the clinic-pathological characteristics of patients. Results: Fifty-seven percent (53/93) of the colorectal carcinomas were bcl-2 protein positive. The positive rate of bcl-2 protein in lymph node involvement cases was lower (15/37) than the cases without node involvement (38/58, P<0.01). The positive rate of p53 protein was 43% (40/93) in colon-rectum carcinomas. No significant correlation was observed between p53 protein expression and clinic-pathological manifestations (P>0.05) but the survival was significantly worse (P=0.0001) in the p53 protein positive cases. Neither bcl-2 nor p53 alone was correlated with stage of the disease. When combined bcl-2/p53 status was analyzed, a group with bcl-2(+) and p53(-) had the best prognosis. This group was significantly associated with earlier Dukes' stages (P=0.1763). In multivariate Cox regression analysis, lymph node involvement and p53 protein expression were two independent factors correlated with survival time. Conclusion: The expression of bcl-2 and p53 represent biological characteristics of colorectal carcinomas. Assessment of both bcl-2 and p53 status may be valuable in predicting the prognosis of patients.

  9. Clinical relevance of BCL2, BCL6, and MYC rearrangements in diffuse large B-cell lymphoma

    NARCIS (Netherlands)

    Kramer, M.H.H.; Hermans, J; Wijburg, E; Philippo, K; Geelen, E; van Krieken, J.H.J.M.; de Jong, D; Maartense, E; Schuuring, E; Kluin, P M

    1998-01-01

    Diffuse large B-cell lymphoma (DLCL) is characterized by a marked degree of morphologic and clinical heterogeneity. We studied 156 patients with de novo DLCL for rearrangements of the BCL2, BCL6, and MYC oncogenes by Southern blot analysis and BCL2 protein expression. We related these data to the pr

  10. Anti-Apoptotic Protein Bcl-xL Expression in the Midbrain Raphe Region Is Sensitive to Stress and Glucocorticoids.

    Directory of Open Access Journals (Sweden)

    Galina T Shishkina

    Full Text Available Anti-apoptotic proteins are suggested to be important for the normal health of neurons and synapses as well as for resilience to stress. In order to determine whether stressful events may influence the expression of anti-apoptotic protein Bcl-xL in the midbrain and specifically in the midbrain serotonergic (5-HT neurons involved in neurobehavioral responses to adverse stimuli, adult male rats were subjected to short-term or chronic forced swim stress. A short-term stress rapidly increased the midbrain bcl-xl mRNA levels and significantly elevated Bcl-xL immunoreactivity in the midbrain 5-HT cells. Stress-induced increase in glucocorticoid secretion was implicated in the observed effect. The levels of bcl-xl mRNA were decreased after stress when glucocorticoid elevation was inhibited by metyrapone (MET, 150 mg/kg, and this decrease was attenuated by glucocorticoid replacement with dexamethasone (DEX; 0.2 mg/kg. Both short-term stress and acute DEX administration, in parallel with Bcl-xL, caused a significant increase in tph2 mRNA levels and slightly enhanced tryptophan hydroxylase immunoreactivity in the midbrain. The increasing effect on the bcl-xl expression was specific to the short-term stress. Forced swim repeated daily for 2 weeks led to a decrease in bcl-xl mRNA in the midbrain without any effects on the Bcl-xL protein expression in the 5-HT neurons. In chronically stressed animals, an increase in tph2 gene expression was not associated with any changes in tryptophan hydroxylase protein levels. Our findings are the first to demonstrate that both short-term stress and acute glucocorticoid exposures induce Bcl-xL protein expression in the midbrain 5-HT neurons concomitantly with the activation of the 5-HT synthesis pathway in these neurons.

  11. Effects of acupoint versus non-acupoint electroacupuncture on cerebral cortical neuronal Bcl-2,Bax and caspase-3 expression in a rat model of focal cerebral ischemia

    Institute of Scientific and Technical Information of China (English)

    Jun Wang; Junming Fan; Yongshu Dong; Xia Huang; Hongxia Zhang

    2008-01-01

    BACKGROUND: Several studies have demonstrated that electroacupuncture by acupoint selection can inhibit cerebral cortical neuronal apoptosis following cerebral ischemia/reperfusion.OBJECTIVE: To validate the effects of electroacupuncture by acupoint selection on the expression level of cortical neuronal anti-apoptotic Bcl-2 protein and the apoptotic executive protein, caspase-3, in rat models of focal cerebral ischemia/reperfusion.DESIGN, TIME AND SETTING: This randomized grouping, neural cell and molecular biology animal experiment was performed at the Laboratory of Pharmacology of Traditional Chinese Medicine and the Laboratory Animal Center of Henan Institute of Traditional Chinese Medicine between November 2006 and May 2007.MATERIALS: Atotal of 40 healthy male adult Sprague-Dawley rats were randomly and evenly divided into four groups: sham-operated, model, electroacupuncture and non-acupoint control. G6895 electro-acupuncture instruments were purchased from Shanghai Huayi Instrument Factory, China. Caspase-3, Bcl-2 and Bax kits were provided by Wuhan Boster Bioengineering Co., Ltd., China.METHODS: Middle cerebral artery occlusion was induced in the model, electroacupuncture and non-acupoint groups. In the electroacupuncture group, the acupoints Jianyu (LI15), Waiguan (SJ5), Biguan (ST31), and Zusanli (ST36) were given electroacupuncture. In the non-acupoint control group, at each time point (immediately after ischemia and after reperfusion, or 2 hours after reperfusion), electroacupuncture was performed at the midpoints of Tianquan (PC2)-Quze (PC 3) line, Quze (PC 3)-Ximen (PC4) line, Zuwuli (LRlO)-Yinbao (LRg) line, and Xiguan (LR7)-Zhongdu (LR6) line. Electroacupuncture parameters were set with a continuous wave with a frequency of 10 Hz, wave width 0.6 ms, voltage 1.5-3.0 V, and a duration of 10 minutes. The sham-operated and model groups received only animal fixation without electroacupuncture procedure.MAIN OUTCOME MEASURES: Five rats were selected from

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

    International Nuclear Information System (INIS)

    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. 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. 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). Bcl-2 expression defines a subgroup of patients with a favorable outcome and may be useful for prognostic stratification of NSCLC patients

  13. 重组人促红细胞生成素对慢性脑缺血大鼠学习记忆能力及凋亡相关蛋白P53和Bcl-2表达的影响%Effects of recombinant human erythropoietin on learning and memory abilities and expressions of P53 and Bcl-2 proteins in rats induced by chronic cerebral ischemia

    Institute of Scientific and Technical Information of China (English)

    周彦慧; 郭军红; 王慧芳; 张金

    2013-01-01

    Objective To study the effects of recombinant human erythropoietin (rhEPO) on learning and memory functions and expressions of apoptosis-related proteins (P53 and Bcl-2) in rats induced by chronic cerebral ischemia.Methods Sixteen healthy male SD rats were randomly divided into control group and experimental group (n=8); the permanent bilateral occlusion of common carotid arteries in these rats was adopted to establish the chronic cerebral ischemia models; rats in the experimental group weekly received intranasal rhEPO delivery at the dose of 150 U/125 μL after chronic ischemia for 3 days,whereas models in the control group accepted equivalent volume of saline at the same time.Eight weeks after the inducement,Morris water maze test was performed to evaluate the movement and the spatial learning and memory capabilities.Morphology changes of cerebral cortex and hippocampal CA1 nerve cells were observed by HE staining.P53 and Bcl-2 proteins levels were detected by immunohistochemistry.The number of apoptotic cells was detected by means of TUNEL.Results Morris water maze test showed that shorter escape latency and higher frequency through platform in the experimental group were noted as compared with those in the control group (P<0.05).HE staining indicated that less pyramidal cells and more serious karyopyknosis changes of cerebral cortex and hippocampal CA1 nerve cells and thinner cerebral cortex in control group were noted as compared with those in the experimental group (P<0.05).Immunohistochemistry indicated that the experiment group had increased Bal-2 expression and mean gray value of P53 as compared with control group (P<0.05).TUNEL showed that the apoptotic cells of control group were significantly increased as compared with those in the experimental group (P<0.05).Conclusion The rhEPO can improve the abilities of movement,memory and spatial orientation in rats induced by chronic cerebral ischemia,whose mechanism might be related to the restrain

  14. Neuroglobin in Breast Cancer Cells: Effect of Hypoxia and Oxidative Stress on Protein Level, Localization, and Anti-Apoptotic Function.

    Directory of Open Access Journals (Sweden)

    Marco Fiocchetti

    Full Text Available The over-expression of human neuroglobin (NGB, a heme-protein preferentially expressed in the brain, displays anti-apoptotic effects against hypoxic/ischemic and oxidative stresses enhancing neuron survival. As hypoxic and oxidative stress injury frequently occurs in fast proliferating neoplastic tissues, here, the effect of these stressors on the level, localization, and anti-apoptotic function of NGB in wild type and NGB-stable-silenced MCF-7 breast cancer cells has been assessed. The well-known endogenous NGB inducer 17β-estradiol (E2 has been used as positive control. The median pO2 present in tumor microenvironment of breast cancer patients (i.e., 2% O2 does not affect the NGB level in breast cancer cells, whereas hydrogen peroxide and lead(IV acetate, which increase intracellular reactive oxygen species (ROS level, enhance the NGB levels outside the mitochondria and still activate apoptosis. However, E2-induced NGB up-regulation in mitochondria completely reverse lead(IV acetate-induced PARP cleavage. These results indicate that the NGB level could represent a marker of oxidative-stress in MCF-7 breast cancer cells; however, the NGB ability to respond to injuring stimuli by preventing apoptosis requires its re-allocation into the mitochondria. As a whole, present data might lead to a new direction in understanding NGB function in cancer opening new avenues for the therapeutic intervention.

  15. Neuroglobin in Breast Cancer Cells: Effect of Hypoxia and Oxidative Stress on Protein Level, Localization, and Anti-Apoptotic Function

    Science.gov (United States)

    Fiocchetti, Marco; Cipolletti, Manuela; Leone, Stefano; Naldini, Antonella; Carraro, Fabio; Giordano, Daniela; Verde, Cinzia; Ascenzi, Paolo; Marino, Maria

    2016-01-01

    The over-expression of human neuroglobin (NGB), a heme-protein preferentially expressed in the brain, displays anti-apoptotic effects against hypoxic/ischemic and oxidative stresses enhancing neuron survival. As hypoxic and oxidative stress injury frequently occurs in fast proliferating neoplastic tissues, here, the effect of these stressors on the level, localization, and anti-apoptotic function of NGB in wild type and NGB-stable-silenced MCF-7 breast cancer cells has been assessed. The well-known endogenous NGB inducer 17β-estradiol (E2) has been used as positive control. The median pO2 present in tumor microenvironment of breast cancer patients (i.e., 2% O2) does not affect the NGB level in breast cancer cells, whereas hydrogen peroxide and lead(IV) acetate, which increase intracellular reactive oxygen species (ROS) level, enhance the NGB levels outside the mitochondria and still activate apoptosis. However, E2-induced NGB up-regulation in mitochondria completely reverse lead(IV) acetate-induced PARP cleavage. These results indicate that the NGB level could represent a marker of oxidative-stress in MCF-7 breast cancer cells; however, the NGB ability to respond to injuring stimuli by preventing apoptosis requires its re-allocation into the mitochondria. As a whole, present data might lead to a new direction in understanding NGB function in cancer opening new avenues for the therapeutic intervention. PMID:27149623

  16. bcl-2 expression is not associated with survival in metastatic cutaneous melanoma: A historical cohort study

    Directory of Open Access Journals (Sweden)

    Corleta Oly C

    2008-06-01

    Full Text Available Abstract Background Programmed cell death (apoptosis has been implicated in tumor development and may affect the metastatic potential of tumor cells. The role of bcl-2, a proto-oncogene that inhibits apoptosis, has been studied in several malignancies, including cutaneous melanoma (CM. The purpose of this study was to evaluate the immunohistochemical expression of bcl-2 in 35 regional lymph node, 28 subcutaneous and 17 visceral CM metastases, correlating the findings with patient survival. Methods In a historical cohort study patient survival was correlated with the expression of bcl-2 in regional lymph node, subcutaneous and visceral metastases of CM. Eighty slides containing surgical specimens from 50 patients diagnosed with stage III and IV CM, 28 male (56% and 22 female (44%, were analyzed. Mean age at diagnosis was 43 years (16–74 years; median = 42 years. Mean Breslow depth was 5.01 mm (0.4–27.5 mm. The slides were submitted to immunohistochemical reaction using anti-bcl-2 monoclonal antibody and classified according to the degree of staining ( 50% of tumor cells stained. The relationship between bcl-2 protein expression and survival for each type of metastasis, gender and age at initial diagnosis was analyzed. Results Mean overall survival was 33.9 months after the diagnosis of the initial metastatic lesion (range: 0 to 131 months. Twenty-four out of 50 patients (48% had died from CM by the end of the study period. bcl-2 expression was detected in 74.3, 85.7 and 82.4% of lymph node, subcutaneous and visceral metastases, respectively. After univariate and multivariate analyses, no correlation was found between positive bcl-2 expression and overall survival for the types of metastases evaluated. Conclusion The immunohistochemical expression of bcl-2 in metastasis alone is not a prognostic marker for CM.

  17. 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

    2012-12-01

    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.

  18. The flavonoid morin from Moraceae induces apoptosis by modulation of Bcl-2 family members and Fas receptor in HCT 116 cells.

    Science.gov (United States)

    Hyun, Hwang-Bo; Lee, Won Sup; Go, Se-Il; Nagappan, Arulkumar; Park, Cheol; Han, Min Ho; Hong, Su Hyun; Kim, Gonsup; Kim, Gi Young; Cheong, Jaehun; Ryu, Chung Ho; Shin, Sung Chul; Choi, Yung Hyun

    2015-01-01

    It is evident based on literature that flavonoids from fruit can safely modulate cancer cell biology and induce apoptosis. Therefore, we investigated the anticancer activity of morin, a flavonoid which is plentiful in twigs of mulberry focusing on apoptosis, and its mechanisms. Morin upregulated the Fas receptor, and activates caspase-8, -9 and -3 in HCT-116 cells. Morin also activates Bid, and induced the loss of mitochondrial membrane potential (MMP, ∆Ψm) with Bax protein activation and cytochrome c release. In addition, morin induced ROS generation which was not blocked by N-acetylcysteine. Morin also suppressed Bcl-2 and cIAP-1, anti-apoptotic proteins, which may contribute to augmentation of morin-triggered apoptosis. As an upstream signaling pathway, suppressed Akt activity by morin was associated to apoptosis. This study suggests that morin induces caspase-dependent apoptosis through extrinsic pathway by upregulating Fas receptor as well as through the intrinsic pathway by modulating Bcl-2 and IAP family members, and ROS generation, and that Akt is the critical upstream signaling that regulates the apoptotic effect of morin in human colon cancer HCT-116 cells.

  19. Immunohistochemical expression of Bcl-2 in oral epithelial dysplasia and oral squamous cell carcinoma

    Directory of Open Access Journals (Sweden)

    S Juneja

    2015-01-01

    Full Text Available BACKGROUND: The B cell lymphoma-2 gene is a proto-oncogene whose protein product inhibits apoptosis. Its role is associated with keeping cells alive, but not by stimulating them to proliferation, as other proto-oncogenes do. Increased expression of protein product of Bcl-2 gene appears in the early phase of carcinogenesis leading to apoptosis impairment and in consequence to the progression of neoplastic changes. OBJECTIVE: To evaluate and compare the expression of Bcl-2 protein in oral epithelial dysplasia and oral squamous cell carcinoma (OSCC. MATERIALS AND METHODS: Sixty cases of formalin-fixed paraffin-embedded archival specimens comprising of 30 cases of leukoplakia with oral epithelial dysplasia and 30 cases of OSCC were taken for immunohistochemical analysis using monoclonal antibody against anti-human Bcl-2 oncoprotein. RESULTS: Immunostaining for Bcl-2 protein was identified in basal and parabasal layers as granular cytoplasmic staining in oral epithelial dysplasia. In OSCC, Bcl-2 immunoreactivity was most prominent in the peripheral cells of the infiltrating tumor islands which diminished toward the center in well-differentiated and moderately differentiated OSCC, whereas stronger and more diffuse expression of Bcl-2 oncoprotein was seen in poorly differentiated OSCC. Overall positivity of 26.7% (8/30 was observed in oral epithelial dysplasia and 30% (9/30 in OSCC in this study. INTERPRETATION AND CONCLUSION: Altered expression of Bcl-2 oncoprotein may be an early molecular event which leads to prolonged cell survival, increased chances of accumulation of genetic alterations, and subsequent increase in malignant transformation potential.

  20. Phyllanthus amarus inhibits cell growth and induces apoptosis in Dalton's lymphoma ascites cells through activation of caspase-3 and downregulation of Bcl-2.

    Science.gov (United States)

    Harikumar, Kuzhuvelil B; Kuttan, Girija; Kuttan, Ramadasan

    2009-06-01

    The authors found in an earlier study that Phyllanthus amarus extract could significantly inhibit the solid and ascites tumor development in mice induced by Dalton's lymphoma ascites (DLA) cells. In the present study, the apoptotic effects of P. amarus against DLA cells in culture was evaluated. P. amarus produced significant reduction in cell viability as determined by the MTT assay. It also induces the formation of apoptotic bodies with characteristic features like plasma membrane invagination, elongation, fragmentation, and chromatin condensation. P. amarus at concentrations of 100 and 200 microg/mL is shown to induce DNA fragmentation. Gene expression analysis reveals that P. amarus induces the expression of caspase-3 and inhibits the expression of Bcl-2, which is an antiapoptotic protein. So the present study provides some insights into the possible mechanism by which P. amarus brings about apoptosis and growth inhibition in DLA cells. PMID:19223368

  1. Green Tea Polyphenols Attenuated Glutamate Excitotoxicity via Antioxidative and Antiapoptotic Pathway in the Primary Cultured Cortical Neurons

    Directory of Open Access Journals (Sweden)

    Lin Cong

    2016-01-01

    Full Text Available Green tea polyphenols are a natural product which has antioxidative and antiapoptotic effects. It has been shown that glutamate excitotoxicity induced oxidative stress is linked to neurodegenerative diseases such as Alzheimer’s disease and Parkinson’s disease. In this study we explored the neuroprotective effect of green teen polyphenols against glutamate excitotoxicity in the primary cultured cortical neurons. We found that green tea polyphenols protected against glutamate induced neurotoxicity in the cortical neurons as measured by MTT and TUNEL assays. Green tea polyphenols were then showed to inhibit the glutamate induced ROS release and SOD activity reduction in the neurons. Furthermore, our results demonstrated that green tea polyphenols restored the dysfunction of mitochondrial pro- or antiapoptotic proteins Bax, Bcl-2, and caspase-3 caused by glutamate. Interestingly, the neuroprotective effect of green tea polyphenols was abrogated when the neurons were incubated with siBcl-2. Taken together, these results demonstrated that green tea polyphenols protected against glutamate excitotoxicity through antioxidative and antiapoptotic pathways.

  2. Genetic suppression of HO-1 exacerbates renal damage: reversed by an increase in the antiapoptotic signaling pathway.

    Science.gov (United States)

    Olszanecki, Rafal; Rezzani, Rita; Omura, Shinji; Stec, David E; Rodella, Luigi; Botros, Fady T; Goodman, Alvin I; Drummond, George; Abraham, Nader G

    2007-01-01

    Apoptosis has been shown to contribute to the development of acute and chronic renal failure. The antiapoptotic action of the heme oxygenase (HO) system may represent an important protective mechanism in kidney pathology. We examined whether the lack of HO-1 would influence apoptosis in clipped kidneys of two-kidney, one-clip (2K1C) rats. Five-day-old Sprague-Dawley rats were injected in the left ventricle with approximately 5 x 10(9) colony-forming units/ml of retrovirus containing rat HO-1 antisense (LSN-RHO-1-AS) or control retrovirus (LXSN). After 3 mo, a 0.25-mm U-shaped silver clip was placed around the left renal artery. Animals were killed 3 wk later. Clipping the renal artery in LSN-RHO-1-AS rats did not result in increased HO-1 expression. In contrast to LXSN animals, 2K1C LSN-RHO-1-AS rats showed increased expression of cyclooxygenase 2 (COX-2) and higher 3-nitrotyrosine (3-NT) content as well as increased expression of the proapoptotic protein Apaf-1 and caspase-3 activity. Clipping the renal artery in LXSN rats resulted in increased expression of the antiapoptotic proteins Bcl-2 and Bcl-xl, while clipping the renal artery in LSN-RHO-1-AS rats did not change Bcl-2 levels and decreased the levels of Bcl-xl. Treatment of LSN-RHO-1-AS rats with cobalt protoporphyrin resulted in induction of renal HO-1, which was accompanied by decreases in blood pressure, COX-2, 3-NT, and caspase-3 activity, and increased expression of anti-apoptotic molecules (Bcl-2, Bcl-xl, Akt and p-Akt) in the clipped kidneys. These findings underscore the prominent role of HO-1 in counteracting apoptosis in this 2K1C renovascular hypertension model. PMID:16940561

  3. 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

    Energy Technology Data Exchange (ETDEWEB)

    Noh, Woo Chul; Ham, Yong Ho [Korea Cancer Center Hospital, Seoul (Korea, Republic of)

    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

  4. Aiolos transcription factor controls cell death in T cells by regulating Bcl-2 expression and its cellular localization.

    Science.gov (United States)

    Romero, F; Martínez-A, C; Camonis, J; Rebollo, A

    1999-01-01

    We searched for proteins that interact with Ras in interleukin (IL)-2-stimulated or IL-2-deprived cells, and found that the transcription factor Aiolos interacts with Ras. The Ras-Aiolos interaction was confirmed in vitro and in vivo by co-immunoprecipitation. Indirect immunofluorescence shows that IL-2 controls the cellular distribution of Aiolos and induces its tyrosine phosphorylation, required for dissociation from Ras. We also identified functional Aiolos-binding sites in the Bcl-2 promoter, which are able to activate the luciferase reporter gene. Mutation of Aiolos-binding sites within the Bcl-2 promoter inhibits transactivation of the reporter gene luciferase, suggesting direct control of Bcl-2 expression by Aiolos. Co-transfection experiments confirm that Aiolos induces Bcl-2 expression and prevents apoptosis in IL-2-deprived cells. We propose a model for the regulation of Bcl-2 expression via Aiolos. PMID:10369681

  5. NF-κB, Bcl-2 and the alcoholic liver disease%NF-κB、Bcl-2与酒精性肝病

    Institute of Scientific and Technical Information of China (English)

    张曦; 王沁

    2011-01-01

    酒精性肝病(ALD)是由于长期过度饮酒而引发的一系列肝脏损害疾病.现研究表明肝细胞的凋亡对该病的发生、发展起着十分重要的作用.其中核因子κB (NF-κB)、B细胞淋巴瘤-2基因(Bcl-2)与ALD关系密切.ALD患者肝细胞内活化的NF-κB,通过刺激大量炎性细胞因子释放,引发肝组织炎症、纤维化、坏死和凋亡,同时通过调控凋亡蛋白酶 (Caspase)、Bcl-2、死亡受体等基因来干预肝细胞凋亡;被激活的Bcl-2,除本身具有抗凋亡功能外,还与NF-κB以复合物的形式发挥抗凋亡作用,同时与同家族促凋亡蛋白Bax以二聚体的形式依比例对肝细胞凋亡发挥抑制或促进作用.肝细胞凋亡和抗凋亡的动态失衡将成为酒精性肝病发病的重要途径之一.%Alcoholic liver disease which causes the liver damage is due to the long series of heavy drinking. Present study shows that the hepatocytes apoptosis plays an important role in the development of ALD. The nuclear factor ΚB (NF-ΚB) and B cell lymphoma-2 genes (Bcl-2) are closely related with the hepatocyte apoptosis. The activate NF-ΚB in the hepatocyte of ALD, not only can stimulate the release of inflammatory cytokines and cause liver inflammation, fibrosis, necrosis and apoptosis, but also can interfere the hepatocyte apoptosis by regulation the caspase (Caspase), Bcl-2, death receptor and other genes. The activated Bcl-2 not only can inhibit apoptosis by itself function, but also can inhibit apoptosis in the form of complex with the activated NF-ΚB. Bcl-2 can be dimer with the same family protein Bax which is the pro-apoptotic protein. The dimer inhibiting or stimulating apoptosis depends on the proportion of Bcl-2 and Bax. Imbalance of stimulating apoptosis and anti-apoptosis will become an important way in the way of ALD pathogenesy.

  6. Effect of Bcl-2 and caspase-3 on calcium distribution in apoptosis of HL-60 cells

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Apoptosis manifests in two major execution programs downstream of the death signal: the caspase pathway and organelle dysfunction. An important antiapoptosis factor, Bcl-2 protein, contributes in caspase pathway of apoptosis. Calcium, an important intracellular signal element in cells, is also observed to have changes during apoptosis, which maybe affected by Bcl2 protein. We have previously reported that in Harringtonine (HT) induced apoptosis of HL-60 cells, there's a change of intracellular calcium distribution, moving from cytoplast especially Golgi's apparatus to nucleus and accumulating there with the highest concentration. We report here that caspase-3 becomes activated in HT-induced apoptosis of HL-60 cells, which can be inhibited by overexpression of Bcl-2 protein. No sign of apoptosis or intracellular calcium movement from Golgi's apparatus to nucleus in HL-60 cells overexpressing Bcl-2 or treated with Ac-DEVD-CHO, a specific inhibitor of caspase-3. The results indicate that activated caspase-3 can promote the movement of intracellular calcium from Golgi's apparatus to nucleus, and the process is inhibited by Ac-DEVD-CHO (inhibitor of caspas-3), and that Bcl-2 can inhibit the movement and accumulation of intracellular calcium in nucleus through its inhibition on caspase3. Calcium relocalization in apoptosis seems to be irreversible, which is different from the intracellular calcium changes caused by growth factor.

  7. MDA-7/IL-24 induces Bcl-2 denitrosylation and ubiquitin-degradation involved in cancer cell apoptosis.

    Directory of Open Access Journals (Sweden)

    Hui Tian

    Full Text Available MDA-7/IL-24 was involved in the specific cancer apoptosis through suppression of Bcl-2 expression, which is a key apoptosis regulatory protein of the mitochondrial death pathway. However, the underlying mechanisms of this regulation are unclear. We report here that tumor-selective replicating adenovirus ZD55-IL-24 leads to Bcl-2 S-denitrosylation and concomitant ubiquitination, which take part in the 26S proteasome degradation. IL-24-siRNA completely blocks Bcl-2 ubiquitination via reversion of Bcl-2 S-denitrosylation and protects it from proteasomal degradation which confirmed the significant role of MDA-7/IL-24 in regulating posttranslational modification of Bcl-2 in cancer cells. Nitric oxide (NO is a key regulator of protein S-nitrosylation and denitrosylation. The NO donor, sodium nitroprusside (SNP, down-regulates Bcl-2 S-denitrosylation, attenuates Bcl-2 ubiquitination and subsequently counteracts MDA-7/IL-24 induced cancer cell apoptosis, whereas NO inhibitor 2-(4-carboxyphenyl-4,4,5,5-tetramethylimidazoline-1-oxy-3-oxide (PTIO shows the opposite effect. At the same time, these NO modulators fail to affect Bcl-2 phosphorylation, suggesting that NO regulates Bcl-2 stability in a phosphorylation-independent manner. In addition, Bcl-2 S-nitrosylation reduction induced by ZD55-IL-24 was attributed to both iNOS decrease and TrxR1 increase. iNOS-siRNA facilitates Bcl-2 S-denitrosylation and ubiquitin-degradation, whereas the TrxR1 inhibitor auranofin prevents Bcl-2 from denitrosylation and ubiquitination, thus restrains the caspase signal pathway activation and subsequent cancer cell apoptosis. Taken together, our studies reveal that MDA-7/IL-24 induces Bcl-2 S-denitrosylation via regulation of iNOS and TrxR1. Moreover, denitrosylation of Bcl-2 results in its ubiquitination and subsequent caspase protease family activation, as a consequence, apoptosis susceptibility. These findings provide a novel insight into MDA-7/IL-24 induced growth

  8. Methionine adenosyltransferase α2 sumoylation positively regulate Bcl-2 expression in human colon and liver cancer cells.

    Science.gov (United States)

    Tomasi, Maria Lauda; Ryoo, Minjung; Ramani, Komal; Tomasi, Ivan; Giordano, Pasquale; Mato, José M; Lu, Shelly C

    2015-11-10

    Ubiquitin-conjugating enzyme 9 (Ubc9) is required for sumoylation and inhibits apoptosis via Bcl-2 by unknown mechanism. Methionine adenosyltransferase 2A (MAT2A) encodes for MATα2, the catalytic subunit of the MATII isoenzyme that synthesizes S-adenosylmethionine (SAMe). Ubc9, Bcl-2 and MAT2A expression are up-regulated in several malignancies. Exogenous SAMe decreases Ubc9 and MAT2A expression and is pro-apoptotic in liver and colon cancer cells. Here we investigated whether there is interplay between Ubc9, MAT2A and Bcl-2. We used human colon and liver cancer cell lines RKO and HepG2, respectively, and confirmed key finding in colon cancer specimens. We found MATα2 can regulate Bcl-2 expression at multiple levels. MATα2 binds to Bcl-2 promoter to activate its transcription. This effect is independent of SAMe as MATα2 catalytic mutant was also effective. MATα2 also directly interacts with Bcl-2 to enhance its protein stability. MATα2's effect on Bcl-2 requires Ubc9 as MATα2's stability is influenced by sumoylation at K340, K372 and K394. Overexpressing wild type (but not less stable MATα2 sumoylation mutants) protected from 5-fluorouracil-induced apoptosis in both colon and liver cancer cells. Colon cancer have higher levels of sumoylated MATα2, total MATα2, Ubc9 and Bcl-2 and higher MATα2 binding to the Bcl-2 P2 promoter. Taken together, Ubc9's protective effect on apoptosis may be mediated at least in part by sumoylating and stabilizing MATα2 protein, which in turn positively maintains Bcl-2 expression. These interactions feed forward to further enhance growth and survival of the cancer cell.

  9. Dexamethasone protected human glioblastoma U87MG cells from temozolomide induced apoptosis by maintaining Bax:Bcl-2 ratio and preventing proteolytic activities

    Directory of Open Access Journals (Sweden)

    Patel Sunil J

    2004-12-01

    Full Text Available Abstract Background Glioblastoma is the deadliest and most prevalent brain tumor. Dexamethasone (DXM is a commonly used steroid for treating glioblastoma patients for alleviation of vasogenic edema and pain prior to treatment with chemotherapeutic drugs. Temozolomide (TMZ, an alkylating agent, has recently been introduced in clinical trials for treating glioblastoma. Here, we evaluated the modulatory effect of DXM on TMZ induced apoptosis in human glioblastoma U87MG cells. Results Freshly grown cells were treated with different doses of DXM or TMZ for 6 h followed by incubation in a drug-free medium for 48 h. Wright staining and ApopTag assay showed no apoptosis in cells treated with 40 μM DXM but considerable amounts of apoptosis in cells treated with 100 μM TMZ. Apoptosis in TMZ treated cells was associated with an increase in intracellular free [Ca2+], as determined by fura-2 assay. Western blot analyses showed alternations in the levels of Bax (pro-apoptotic and Bcl-2 (anti-apoptotic proteins resulting in increased Bax:Bcl-2 ratio in TMZ treated cells. Western blot analyses also detected overexpression of calpain and caspase-3, which cleaved 270 kD α-spectrin at specific sites for generation of 145 and 120 kD spectrin break down products (SBDPs, respectively. However, 1-h pretreatment of cells with 40 μM DXM dramatically decreased TMZ induced apoptosis, decreasing Bax:Bcl-2 ratio and SBDPs. Conclusion Our results revealed an antagonistic effect of DXM on TMZ induced apoptosis in human glioblastoma U87MG cells, implying that treatment of glioblastoma patients with DXM prior to chemotherapy with TMZ might result in an undesirable clinical outcome.

  10. bcl-2在受损面神经运动神经元中的表达与定位%Expression of bcl-2 in facial motoneurons and its ultrastructural localization following facial nerve injury

    Institute of Scientific and Technical Information of China (English)

    戴春富; 黄新生; 王正敏; 李宽俨; 赵晖

    2001-01-01

    Objective To explore the expression of bcl-2 in facial motoneurons and its subcellular distribution. Methods Wistar rats were used in this study. Facial nerve transection was performed at stylomastoid foramen or internal acoustic meatus. Facial nerve crush was made at stylomastiod foramen. The animal survived for 1, 3, 7, 15, 30 and 60 days respectively. Facial nucleus was treated with bcl-2 monoclonal antibody or bcl-2 DIG-labelling probe and studied with immunohistochemstry and in situ hybridization. The bcl-2 positive motoneuron was investigated with immuno-electron microscope. Results It was demonstrated that bcl-2 protein level was corresponded with bcl-2 mRNA expression. The level of bcl-2 expression in facial motoneurons was high in normal facial nerve. It increased on the first day and declined on the third day post-transection in facial motoneuron. It reached the lowest level on the 15th days following facial nerve injury (P0.05). After facial nerve transected, the reduction of bcl-2 expression was more significant when facial nerve transected close to facial nucleus than that far from facial nucleus (P0.05)。bcl-2的表达同损伤程度和损伤部位有关(0.01bcl-2 mRNA和bcl-2蛋白表达一致。免疫电镜发现bcl-2蛋白主要定位于神经元胞体中的线粒体、内质网和核膜上。结论 bcl-2转录和翻译可能同面神经核团中运动神经元胞体的死亡相关。通过转基因技术调节bcl-2基因的表达,可能为临床面瘫的治疗提供新的手段。

  11. Pan-Bcl-2 inhibitor AT-101 enhances tumor cell killing by EGFR targeted T cells.

    Directory of Open Access Journals (Sweden)

    Archana Thakur

    Full Text Available Pancreatic cancer is a deadly disease and has the worst prognosis among almost all cancers and is in dire need of new and improved therapeutic strategies. Conditioning of tumor cells with chemotherapeutic drug has been shown to enhance the anti-tumor effects of cancer vaccines and adoptive cell therapy. In this study, we investigated the immunomodulatory effects of pan-Bcl-2 inhibitor AT-101 on pancreatic cancer (PC cell cytotoxicity by activated T cells (ATC. The effects of AT-101 on cytotoxicity, early apoptosis, and Granzyme B (GrzB and IFN-γ signaling pathways were evaluated during EGFR bispecific antibody armed ATC (aATC-mediated killing of L3.6pl and MiaPaCa-2 PC cells pre-sensitized with AT-101. We found that pretreatment of tumor cells with AT-101 enhanced susceptibility of L3.6pl and MiaPaCa-2 tumor cells to ATC and aATC-mediated cytotoxicity, which was in part mediated via enhanced release of cytolytic granule GrzB from ATC and aATC. AT-101-sensitized L3.6pl cells showed up-regulation of IFN-γ-mediated induction in the phosphorylation of Ser(727-Stat1 (pS(727-Stat1, and IFN-γ induced dephosphorylation of phospho-Tyr(705-Stat3 (pY(705-Stat3. Priming (conditioning of PC cells with AT-101 can significantly enhance the anti-tumor activity of EGFRBi armed ATC through increased IFN-γ induced activation of pS(727-Stat1 and inhibition of pY(705-Stat3 phosphorylation, and resulting in increased ratio of pro-apoptotic to anti-apoptotic proteins. Our results verify enhanced cytotoxicity after a novel chemotherapy conditioning strategy against PC that warrants further in vivo and clinical investigations.

  12. Methane attenuates retinal ischemia/reperfusion injury via anti-oxidative and anti-apoptotic pathways.

    Science.gov (United States)

    Liu, Lin; Sun, Qinglei; Wang, Ruobing; Chen, Zeli; Wu, Jiangchun; Xia, Fangzhou; Fan, Xian-Qun

    2016-09-01

    Retinal ischemia/reperfusion injury (IRI) may cause incurable visual impairment due to neural regeneration limits. Methane was shown to exert a protective effect against IRI in many organs. This study aims to explore the possible protective effects of methane-rich saline against retinal IRI in rat. Retinal IRI was performed on the right eyes of male Sprague-Dawley rats, which were immediately injected intraperitoneally with methane-saturated saline (25ml/kg). At one week after surgery, the number of retinal ganglion cells (RGCs), total retinal thickness, visual function were measured by hematoxylin and eosin staining, FluoroGold anterograde labeling and flash visual evoked potentials. The levels of 8-hydroxy-2-deoxyguanosine (8-OHdG), 4-Hydroxy-2-nonenal (4-HNE), malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), caspase-3, caspase-9, B cell lymphoma/leukemia-2 (Bcl-2) and Bcl-2 associated X protein (Bax) in retinas were assessed by immunofluorescence staining, enzyme-linked immunosorbent assay and quantitative polymerase chain reaction. As expected, methane treatment significantly improved the retinal IRI-induced RGC loss, total retinal layer thinning and visual dysfunction. Moreover, methane treatment significantly reduced the levels of oxidative stress biomarkers (8-OHdG, 4-HNE, MDA) and increased the antioxidant enzyme activities (SOD, CAT, GPx) in the retinas with IRI. Meanwhile, methane treatment significantly increased the anti-apoptotic gene (Bcl-2) expression and decreased the pro-apoptotic gene (Bax) expression, accompanied by the suppression of caspase-3 and caspase-9 activity. Thus, these data demonstrated that methane can exert a neuroprotective role against retinal IRI through anti-oxidative and anti-apoptotic pathways. PMID:27208496

  13. THE OVEREXPRESSION OF APOPTOSIS -RELATED GENES OF P53 AND BCL-2 IN CERVICAL CARCINOMA

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Objective To investigate the significance of overexpression of P53 and bcl-2 protein in carcinogenesis of cervix. Methods 10 cases of cervical intraepithelial neoplasis(CIN) and 57 cases of invasive cancer were investigated with immunohistochemistry technique. Results The overexpresion of P53 protein in CIN and cervical cancer was significantly higher than that of control, respectively (P<0.01). But there was no significant difference between CIN and cervical cancer(P>0. 05). The immunoreactivity of bcl-2 in CIN was much more higher than that of control (P<0.05). The positive rate and immunoreactivity of bcl-2 in cervical carcinoma were both remarkably higher than those of control (P<0. 01) ,but there was no significant difference between CIN and cervical carcinoma (P>0. 05). It was also found that there was a remarkably positive correlation between the overexpression of bcl-2 and P53 (P<0.01). Conclusion Because of the loss of wtP53 function,the expression of bcl-2 can not be down-reguated,which is associated with the pathogenesis and development of cervical carcinoma.

  14. Loss of BH3-only Protein Bim Inhibits Apoptosis of Hemopoietic Cells in the Fetal Liver and Male Germ Cells but Not Neuronal Cells in Bcl-x–deficient Mice

    OpenAIRE

    Akhtar, Rizwan S.; Klocke, Barbara J.; Strasser, Andreas; Roth, Kevin A.

    2008-01-01

    Members of the Bcl-2 family include pro- and antiapoptotic proteins that regulate programmed cell death of developing tissues and death in response to cellular damage. In developing mice, the antiapoptotic Bcl-xL is necessary for survival of neural and hematopoietic cells, and consequently, bcl-x–deficient mice die around Day 13.5 of embryogenesis. Furthermore, adult bcl-x+/− heterozygous male mice have reduced fertility because of testicular degeneration. Bax, a multi-BH (Bcl-2 homology) dom...

  15. HAMLET triggers apoptosis but tumor cell death is independent of caspases, Bcl-2 and p53.

    Science.gov (United States)

    Hallgren, O; Gustafsson, L; Irjala, H; Selivanova, G; Orrenius, S; Svanborg, C

    2006-02-01

    HAMLET (Human alpha-lactalbumin Made Lethal to Tumor cells) triggers selective tumor cell death in vitro and limits tumor progression in vivo. Dying cells show features of apoptosis but it is not clear if the apoptotic response explains tumor cell death. This study examined the contribution of apoptosis to cell death in response to HAMLET. Apoptotic changes like caspase activation, phosphatidyl serine externalization, chromatin condensation were detected in HAMLET-treated tumor cells, but caspase inhibition or Bcl-2 over-expression did not prolong cell survival and the caspase response was Bcl-2 independent. HAMLET translocates to the nuclei and binds directly to chromatin, but the death response was unrelated to the p53 status of the tumor cells. p53 deletions or gain of function mutations did not influence the HAMLET sensitivity of tumor cells. Chromatin condensation was partly caspase dependent, but apoptosis-like marginalization of chromatin was also observed. The results show that tumor cell death in response to HAMLET is independent of caspases, p53 and Bcl-2 even though HAMLET activates an apoptotic response. The use of other cell death pathways allows HAMLET to successfully circumvent fundamental anti-apoptotic strategies that are present in many tumor cells.

  16. Temporal Alterations in Cellular Bax:Bcl-2 Ratio following Traumatic Brain Injury in the Rat

    OpenAIRE

    Raghupathi, Ramesh; Strauss, Kenneth I.; Zhang, Chen; Krajewski, Stanislaw; Reed, John C.; McIntosh, Tracy K.

    2003-01-01

    Cell death/survival following CNS injury may be a result of alterations in the intracellular ratio of death and survival factors. Using immunohistochemistry, Western analysis and in situ hybridization, the expression of the anti-cell death protein, Bcl-2, and the pro-cell death protein, Bax, was evaluated following lateral fluid-percussion (FP) brain injury of moderate severity (2.3–2.6 atm) in adult male Sprague-Dawley rats. By 2 h post-injury, a marked reduction of cellular Bcl-2-immunoreac...

  17. Insulin resistance contributes to multidrug resistance in HepG2 cells via activation of the PERK signaling pathway and upregulation of Bcl-2 and P-gp.

    Science.gov (United States)

    Liu, Xinyue; Li, Linjing; Li, Jing; Cheng, Yan; Chen, Jing; Shen, Minghui; Zhang, Shangdi; Wei, Hulai

    2016-05-01

    Liver tumorigenesis frequently causes insulin resistance which may be used as an independent risk factor for evaluation of survival and post-surgery relapse of liver cancer patients. In the present study, HepG2/IR, an insulin resistant HepG2 cell line, was established by exposing HepG2 cells to 0.5 µmol/l of insulin for 72 h, and comparison of HepG2/IR with the parental HepG2 cells indicated that the HepG2/IR cells showed significantly enhanced resistance to the most frequently used chemotherapeutics for solid tumors, such as cisplatin, 5-fluorouracil, vincristine and mitomycin. Flow cytometric analysis of cisplatin-treated HepG2/IR cells showed a significantly decreased hypodiploid peak and a significantly downregulated expression level of pro-apoptotic protein caspase-3 compared with the parental HepG2 cells. Our data further showed swollen endoplasmic reticulum (ER) in the cisplatin-treated HepG2/IR cells with significantly increased levels of glucose-regulated protein 78 (GRP78), phosphorylated protein kinase R-like ER kinase (p-PERK) and P-glycoprotein (P-gp). There was also an upregulated expression of anti-apoptotic protein B-cell lymphoma 2 (Bcl-2) whereas no significant change was observed for CCAAT-enhancer-binding protein homologous protein (CHOP), which is known to be induced by ER stress and to mediate apoptosis. Our results demonstrated that insulin resistance in HepG2 cells promoted a protective unfolded protein response and upregulated the expression of ER chaperone protein GRP78, which resulted in the phosphorylation of PERK kinase to activate the PERK-mediated ER stress signal transduction pathway and the upregulation of Bcl-2 and P-gp, leading to the inhibition of the caspase-3-dependent apoptosis pathway and to the survival of liver tumor cells. PMID:26935266

  18. The expression of antiapoptotic protein survivin is transcriptionally upregulated by DEC1 primarily through multiple sp1 binding sites in the proximal promoter

    OpenAIRE

    Li, Y.; Xie, M.; Yang, J; D. Yang; Deng, R.; Wan, Y; B. Yan

    2006-01-01

    Human differentially expressed in chondrocytes (DEC), mouse stimulated with retinoic acid and rat split and hairy related proteins constitute a structurally distinct class of the basic helix-loop-helix proteins. DEC1is abundantly expressed in tumors and protects against apoptosis induced by serum starvation. In this study, we report that DEC1 antiapoptosis is achieved by inducing survivin, an antiapoptotic protein. In paired tumor–normal tissues, survivin and DEC1 exhibited a paralleled expre...

  19. Effect of U-74389G on apoptosis and bcl-2 expression following traumatic brain injury in rats

    Institute of Scientific and Technical Information of China (English)

    骆纯; 卢亦成; 朱诚; 江基尧

    2003-01-01

    Objective: To investigate the relationship between oxidative stress and apoptosis and bcl-2 expression following traumatic brain injury (TBI). Methods: Male Sprague-Dawley rats were subjected to lateral fluid percussion brain injury (FPBI) of moderate severity. U-74389G (20 mg/kg) were administered intravenously before FPBI. The neurological functions were measured by beam-walk task (BWT) and beam-balance task (BBT). In addition to morphological evidence of apoptosis, TUNEL histochemistry was used to identify DNA fragmentation in situ with both light and electron microscopic levels. The internucleosomal fragments of DNA in apoptotic cells were examined using agarose gel electrophoresis. Bcl-2 protein expression was detected by immunohistochemistry. Results: The scores of BWT and BBT were significantly improved (P<0.01) in the treated animals. The treatment significantly reduced the number of apoptotic cells that was counted in the areas of the injured hemisphere at various time points following TBI. No DNA ladder was detected in the treated rats. Bcl-2 expression was observed in the cerebral cortex, subcortical white matter, dentate gyrus, hippocampal CA1 and CA3 region ipsilateral to injured hemisphere. Bcl-2 positive cells displayed normal nuclear morphology; Little Bcl-2 positive cells revealed morphological feature of apoptosis or necrosis. The immunoreactivity of Bcl-2 protein decreased significantly in the hippocampus ipsilateral impact site as early as 6 h post-injury. During 1-3 d after injury, the bcl-2 protein expression decreased relatively slow. In the U-74389G treated groups, the downregulation of bcl-2 expression was halted. Conclusion: In this model, apoptosis is associated with an activation of lipid peroxidation. U-74389G may block oxidative stress and halt the downregulation of bcl-2 expression. These may be one of the molecular mechanisms of the neuro-protective effects by U-74389G.

  20. Effect of silencing Bcl-2 expression by small interfering RNA on radiosensitivity of gastric cancer BGC823 cells

    Institute of Scientific and Technical Information of China (English)

    Hong-Tao Liu; Chun-Lei Lu

    2013-01-01

    Objective: To explore the influence of silencing Bcl-2 expression by small interfering RNA (siRNA) on Bcl-2 protein expression, cell apoptosis rate and radiosensitivity of gastric cancer BGC823 cells. Methods: siRNA segment for Bcl-2 gene was designed and synthesized, then was induced into gastric cancer BGC 823 cells by liposome transfection. Bcl-2 protein expression was detected by Western Blotting. After X radiation, flow cytometry and clone forming assay were used to determine the effects of RNA interference on BGC823 cell apoptosis rate and radiosensitivity.Result:After the transfection of Bcl-2 siRNA, the positive expression rate of Bcl-2 protein in BGC823 cells was (35.45±2.35)%. Compared with the control group and negative siRNA transfection group, the rate was significantly decreased (P<0.01). The apoptosis rate of BGC823-RNAi cell was (10.81±0.91)%, which was significantly higher than the control group and negative siRNA transfection group (P<0.01). After 48h X radiation, the apoptosis rate of BGC823-RNAi was (28.91 ±1.40)%, which was significantly higher than the control group and the group without radiation (P<0.01). During clone forming assay D0, Dq and SF2 values in Bcl-2 siRNA1 transfection group were all lower than those in the control group. The radiosensitivity ratio was 1.28 (the ratio of D0) and 1.60 (the ratio of Dq). Conclusions: Specific siRNA of Bcl-2 gene can effectively inhibit the expression of Bcl-2 gene, enhance the radiosensitivity and apoptosis of gastric cancer BGC823 cells, having good clinical application perspective.

  1. Bcl-2-dependent upregulation of autophagy by sequestosome 1/p62 in vitro

    Institute of Scientific and Technical Information of China (English)

    Liang ZHOU; Hong-feng WANG; Hai-gang REN; Dong CHEN; Feng GAO; Qing-song HU; Chen FU

    2013-01-01

    To investigate whether sequestosome 1/p62 (p62),a key cargo adaptor protein involved in both the ubiquitin-proteasome system and the autophagy-lysosome system,could directly regulate autophagy in vitro.Methods:HEK 293 cells or HeLa cells were transfected with p62-expressing plasmids or siRNA targeting p62.The cells or the cell lysates were subsequently subjected to immunofluorescence assay,immunoprecipitation assay,or immunoblot analysis.In vitro pulldown assay was used to study the interaction of p62 with Bcl-2.Results:Overexpression of p62 significantly increased the basal level of autophagy in both HEK 293 cells and HeLa cells,whereas knockdown of p62 significantly decreased the basal level of autophagy.In vitro pulldown assay showed that p62 directly interacted with Bcl-2.It was observed in HeLa cells that p62 co-localized with Bcl-2.Furthermore,knockdown of p62 in HEK 293 cells significantly increased the amount of Beclin 1 that co-immunoprecipitated with Bcl-2.Conclusion:p62 induces autophagy by disrupting the association between Bcl-2 and Beclin 1.

  2. Serum level of IL13 and expression of BCL2 in Behcet's disease

    Directory of Open Access Journals (Sweden)

    Hanan.M.A Darwish*, Sabila Gomaa Mousa** Noha Hamdy

    2006-09-01

    Full Text Available Background BD: BCL2 family is a large family of apoptosis regulating proteins consisting of both blockers and promoters of cell death. Immunological processes and a variety of cytokines may play a role in pathophysiological process. Defective regulation of programmed cell death (apoptosis also play a role in development of Behcet's disease Objective: To investigate the level of BCL2 and IL13in BD and to determine their to relation monitory disease activity. Patients and methods: This study was conducted on thirty patients (15 active and 15 inactive and 15-health control, the activity of BD was evaluated according to international study group for BD disease, using ELISA technique for IL 13 and flow cytometry forBCL2. Results: Elevated serum levels of IL13 in patient with active BD than inactive and both had elevated levels than control(P< 0.01 and also the serum levels of Bcl2 was elevated in patient with active BD than inactive and control(P< 0.01. Concolusion: The data suggested that IL13 and BCL2 could be involved in the pathogenesis of BD and its serum levels can be used as marker to monitor disease activity.

  3. Piezometric biosensors for anti-apoptotic protein survivin based on buried positive-potential barrier and immobilized monoclonal antibodies.

    Science.gov (United States)

    Stobiecka, Magdalena; Chalupa, Agata; Dworakowska, Beata

    2016-10-15

    The anti-apoptotic protein survivin (Sur) plays an important role in the regulation of cell division and inducing the chemotherapeutic drug resistance. The Sur protein and its mRNA have recently been studied as cancer biomarkers and potential targets for cancer therapy. In this work, we have focused on the design of immunosensors for the detection of Sur based on buried positive-potential barrier layer structure and anti-survivin antibody. The modification of solid AuQC piezoelectrodes was monitored by recording the resonance frequency shift and electrochemical measurements during each step of the sensor preparation. Our results indicate that the immunosensor with covalently bound monoclonal anti-survivin antibody can detect Sur with the limit of detection, LOD=1.7nM (S/N=3σ). The immunosensor applicability for the analysis of real samples was assessed by testing samples of cell lysate solutions obtained from human astrocytoma (glioblastoma) U-87MG cell line, with the experiments performed using the standard addition method. The good linearity of the calibration curves for PBS and lysate solutions at low Sur concentrations confirm the high specificity of the proposed biosensor and good discrimination against nonspecific interactions with lysate components. The calculations indicate that there is still room to increase the Sur capture capacity for Sur while miniaturizing the sensor. The important advantage of the sensor is that it can be reused by a simple regeneration procedure. PMID:26507667

  4. IMPORTANCE OF APOPTOSIS MARKERS (MDM2, BCL-2 AND Bax) IN CONVENTIONAL RENAL CELL CARCINOMA.

    Science.gov (United States)

    Saker, Z; Tsintsadze, O; Jiqia, I; Managadze, L; Chkhotua, A

    2015-12-01

    The goal of the current study was to analyze the expression of Bcl-2, MDM2 and Bax in benign and malignant renal tissue samples and assess their possible association with different clinical parameters. Prognostic significance of the markers in recurrence-free and cancer-specific survivals has also been evaluated. Activity of MDM2, Bcl-2 and Bax was evaluated in: 24 normal human kidney tissues resected from the patients of different ages (range: 21-80 years), and in 52 conventional RCC samples. Intensity of the markers' expression was compared between the groups and correlation was analyzed with different clinical parameters. Activity of anti-apoptotic MDM2 and Bcl-2 was significantly elevated while activity of pro-apoptotic Bax was decreased in RCC as compared with normal kidney tissues. Bax expression was positively correlated with patient age. Significant association has been detected between the evaluated markers and cancer clinical parameters like: tumor stage, grade, lymph node and distant metastases. The markers' activity was associates with the tumor morphological features, in particular: presence of tumor necrosis and microvascular invasion. Disease recurrence and 5-year patient survival were associated with the markers' activity. Cox regression analyses have shown that tumor size, pathological stage and grade are the risk factors for disease recurrence and patient death. Expression of MDM2 and Bcl-2 is significantly up-regulated, while Bax is down-regulated in RCC as compared with normal kidney tissue. Intensity of the markers'activities is associated with the tumor pathological and clinical parameters (stage, grade, lymph node and distant metastases, tumor recurrence and patient survival). Further studies with more patients and longer follow-up will uncover the clinical importance of the evaluated markers in RCC. PMID:26719546

  5. Reversal of multidrug resistance in MCF-7/Adr cells by codelivery of doxorubicin and BCL2 siRNA using a folic acid-conjugated polyethylenimine hydroxypropyl-β-cyclodextrin nanocarrier

    Directory of Open Access Journals (Sweden)

    Li JM

    2015-04-01

    Full Text Available Jin-Ming Li, Wei Zhang, Hua Su, Yuan-Yuan Wang, Cai-Ping Tan, Liang-Nian Ji, Zong-Wan Mao MOE Key Laboratory of Bioinorganic and Synthetic Chemistry, School of Chemistry and Chemical Engineering, Sun Yat-sen University, Guangzhou, People’s Republic of China Abstract: Systemic administration of chemotherapy for cancer often faces drug resistance, limiting its applications in cancer therapy. In this study, we developed a simple multifunctional nanocarrier based on polyethylenimine (PEI to codeliver doxorubicin (DOX and BCL2 small interfering RNA (siRNA for overcoming multidrug resistance (MDR and enhancing apoptosis in MCF-7/Adr cancer cells by combining chemotherapy and RNA interference (RNAi therapy. The low-molecular-weight branch PEI was used to conjugate hydroxypropyl-β-cyclodextrin (HP-β-CD and folic acid (FA, forming the codelivery nanocarrier (FA-HP-β-CD-PEI to encapsulate DOX with the cavity HP-β-CD and bind siRNA with the positive charge of PEI for tumor-targeting codelivering drugs. The drug-loaded nanocomplexes (FA-HP-β-CD-PEI/DOX/siRNA showed uniform size distribution, high cellular uptake, and significant gene suppression of BCL2, displaying the potential of overcoming MDR for enhancing the effect of anticancer drugs. Furthermore, the nanocomplexes achieved significant cell apoptosis through a mechanism of downregulating the antiapoptotic protein BCL2, resulted in improving therapeutic efficacy of the coadministered DOX by tumor targeting and RNA interference. Our study indicated that combined RNAi therapy and chemotherapy using our functional codelivery nanocarrier could overcome MDR and enhance apoptosis in MDR cancer cells for a potential application in treating MDR cancers. Keywords: tumor targeting, codelivery, doxorubicin, BCL2 siRNA, overcome multidrug resistance

  6. Effect of nitric oxide with different doses on Bcl-2/Bax in spinal dorsal horn in rats induced by formalin%不同剂量的一氧化氮对福尔马林炎性痛大鼠脊髓背角Bcl-2/Bax表达的影响

    Institute of Scientific and Technical Information of China (English)

    未小明; 李宽; 祁文秀

    2011-01-01

    Objective: To investigate the effects of multiple application of different doses of nitric oxide (NO) on Bcl-2/ Bax in spinal dorsal horn induced by formalin. Methods: A succession of 4 d intrathecal injection of NO precursor L-arginine (L-Arg)10 μg/d (low L-Arg group) or 250 μg/d (high L-Arg group) or NOS inhibitor Nω-nitro-L-arginine methylester (L-NAME) 2700 μg/d (L-NAME group) in rats, and normal saline (NS group) was applied as a control, and administration once a day. Then rats were subcutaneously injected formalin (2%, 100 μL) into the right hindpaw, four hours later after formalin injection, Bcl-2 or Bax protein expression were detected with immunocytochemistry and Western Blot. Results: The immunocytochemistry showed the distributions of Bcl-2 and Bax were in both sides of the dorsal horn,especially in superficial laminae, and the expressions of bcl-2 and bax in the ipsilateral side of formalin injection were significantly increased than that in contralateral side of formalin injection in all four groups; the ratio of Bcl-2/Bax with Western-Blot was increased in low L-Arg group compared with normal saline group and was all decreased in high L-Arg group or L-NAME group compared with normal saline group. bcl-2 and bax are two major genes in the regulation of apoptosis, bcl-2 inhibits apoptosis and bax promotes apoptosis. Conclusion: Therefore, in inflammatory pain model, low doses of NO can promote the antiapoptotic gene expression, while high doses of NO and insufficient of NO both can promote pro-apoptotic gene expression, which affect the incidence of inflammatory pain.%目的:探讨多次应用不同剂量的一氧化氮(NO)对福尔马林炎性痛中脊髓背角神经元Bcl-2、Bax表达的影响.方法:连续4 d给大鼠各进行鞘内注射不同剂量的一氧化氮前体左旋精氨酸(L-arginine,L-Arg)10μg/d(低L-Arg组)、250 μg/d(高L-Arg组)或一氧化氮合酶(nitric oxide synthase,NOS)抑制剂Nω-硝基-L

  7. Retinoids cause apoptosis in pancreatic cancer cells via activation of RAR-γ and altered expression of Bcl-2/Bax

    OpenAIRE

    Pettersson, F; Dalgleish, A G; Bissonnette, R P; Colston, K W

    2002-01-01

    All-trans-retinoic acid and 9-cis-retinoic acid have been reported to have inhibitory effects on pancreatic adenocarcinoma cells and we have shown that this is partly due to induction of apoptosis. In this study, the mechanisms whereby 9-cis-retinoic acid induces apoptosis in these cells were investigated. An involvement of the Bcl-2 family of proteins was shown, such that 9-cis-retinoic acid causes a decrease in the Bcl-2/Bax ratio. Overexpression of Bcl-2 also resulted in inhibition of apop...

  8. RBP2 Promotes Adult Acute Lymphoblastic Leukemia by Upregulating BCL2

    Science.gov (United States)

    Wang, Xiaoming; Zhou, Minran; Fu, Yue; Sun, Ting; Chen, Jin; Qin, Xuemei; Yu, Yuan; Jia, Jihui; Chen, Chunyan

    2016-01-01

    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. PMID:27008505

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

    Directory of Open Access Journals (Sweden)

    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.

  10. The effect of marathon on mRNA expression of anti-apoptotic and pro-apoptotic proteins and sirtuins family in male recreational long-distance runners

    Directory of Open Access Journals (Sweden)

    Russo Matteo

    2010-05-01

    Full Text Available Abstract Background A large body of evidence shows that a single bout of strenuous exercise induces oxidative stress in circulating human lymphocytes leading to lipid peroxidation, DNA damage, mitochondrial perturbations, and protein oxidation. In our research, we investigated the effect of physical load on the extent of apoptosis in primary cells derived from blood samples of sixteen healthy amateur runners after marathon (a.m.. Results Blood samples were collected from ten healthy amateur runners peripheral blood mononuclear cells (PBMCs were isolated from whole blood and bcl-2, bax, heat shock protein (HSP70, Cu-Zn superoxide dismutase (SOD, Mn-SOD, inducible nitric oxide synthase (i-NOS, SIRT1, SIRT3 and SIRT4 (Sirtuins RNA levels were determined by Northern Blot analysis. Strenuous physical load significantly increased HSP70, HSP32, Mn-SOD, Cu-Zn SOD, iNOS, GADD45, bcl-2, forkhead box O (FOXO3A and SIRT1 expression after the marathon, while decreasing bax, SIRT3 and SIRT4 expression (P Conclusion These data suggest that the physiological load imposed in amateur runners during marathon attenuates the extent of apoptosis and may interfere with sirtuin expression.

  11. LYMPHOMAS WITH TESTICULAR LOCALIZATION SHOW A CONSISTENT BCL-2 EXPRESSION WITHOUT A TRANSLOCATION(14-18) - A MOLECULAR AND IMMUNOHISTOCHEMICAL STUDY

    NARCIS (Netherlands)

    LAMBRECHTS, AC; LOOIJENGA, LHJ; VANTVEER, MB; VANECHTEN, J; TIMENS, W; OOSTERHUIS, JW

    1995-01-01

    The presence of the BCL-2 protein was studied in nine non-Hodgkin's lymphomas with testicular localisation. A consistent presence of the BCL-2 protein was found. The chromosomal translocation (14;18) was seen neither by cytogenetic analysis (n = 4) nor by polymerase chain reaction amplification and

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

    International Nuclear Information System (INIS)

    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

  13. The B-cell lymphoma 2 (BCL2)-inhibitors, ABT-737 and ABT-263, are substrates for P-glycoprotein

    Energy Technology Data Exchange (ETDEWEB)

    Vogler, Meike, E-mail: mv62@le.ac.uk [MRC Toxicology Unit, University of Leicester, LE1 9HN Leicester (United Kingdom); Dickens, David, E-mail: David.Dickens@liverpool.ac.uk [Department of Molecular and Clinical Pharmacology, Institute of Translational Medicine, University of Liverpool, L69 3GL Liverpool (United Kingdom); Dyer, Martin J.S., E-mail: mjsd1@le.ac.uk [MRC Toxicology Unit, University of Leicester, LE1 9HN Leicester (United Kingdom); Owen, Andrew, E-mail: aowen@liverpool.ac.uk [Department of Molecular and Clinical Pharmacology, Institute of Translational Medicine, University of Liverpool, L69 3GL Liverpool (United Kingdom); Pirmohamed, Munir, E-mail: munirp@liv.ac.uk [Department of Molecular and Clinical Pharmacology, Institute of Translational Medicine, University of Liverpool, L69 3GL Liverpool (United Kingdom); Cohen, Gerald M., E-mail: gmc2@le.ac.uk [MRC Toxicology Unit, University of Leicester, LE1 9HN Leicester (United Kingdom)

    2011-05-06

    Highlights: {yields} The BCL2-inhibitor ABT-263 is a substrate for P-glycoprotein. {yields} Apoptosis is inhibited by P-glycoprotein expression. {yields} Overexpression of P-glycoprotein may contribute to resistance to ABT-263 or ABT-737. -- Abstract: Inhibition of BCL2 proteins is one of the most promising new approaches to targeted cancer therapy resulting in the induction of apoptosis. Amongst the most specific BCL2-inhibitors identified are ABT-737 and ABT-263. However, targeted therapy is often only effective for a limited amount of time because of the occurrence of drug resistance. In this study, the interaction of BCL2-inhibitors with the drug efflux transporter P-glycoprotein was investigated. Using {sup 3}H labelled ABT-263, we found that cells with high P-glycoprotein activity accumulated less drug. In addition, cells with increased P-glycoprotein expression were more resistant to apoptosis induced by either ABT-737 or ABT-263. Addition of tariquidar or verapamil sensitized the cells to BCL2-inhibitor treatment, resulting in higher apoptosis. Our data suggest that the BCL2-inhibitors ABT-737 and ABT-263 are substrates for P-glycoprotein. Over-expression of P-glycoprotein may be, at least partly, responsible for resistance to these BCL2-inhibitors.

  14. Combined expression of gastrointestinal hormone SP and anti-apoptosis geneBcl-2 in gastric carcinoma

    Institute of Scientific and Technical Information of China (English)

    Yan Ling Feng; Qin Xian Zhang; Sheng Lei Li

    2000-01-01

    AIM To study the combined expression of gastrointestinal hormone substance P and anti-apoptosis gene Bcl-2 in gastric carcinoma and its significance.METHODS Substance P and Bcl-2 protein expression was examined by the S-P immunohistochemicalmethod in 33 cases of gastric carcinoma, 17 adjacent the carcinoma and 13 normal gastric mucoma.RESULTS Positive expression of SP in gastric carcinoma was higher than that of both adjacent and normalmucosa (P 0.05). The expression of bcl-2 both in gastric carcinoma and adjacent tissues werehigher than that of normal gastric mucosa (P< 0.05-0.01). But the positive expression of Bcl-2 had nostatistical significance between gastric carcinoma and adjacent tissues.CONCLUSION Both gastrointestinal hormone SP and Bcl-2 gene have synergistic expression in gastriccarcinoma, indicating that they all take part in the occurrence of gastric carcinoma. Abnormal expression ofBcl-2 gene occurred in benign gastric pathological changes, once they become carcinoma, the positiveexpression of cell is no more increased, possibly because that there is no more increase of the intensity of Bcl-2 inhibition of cell apoptosis.

  15. Transformer 2β and miR-204 regulate apoptosis through competitive binding to 3' UTR of BCL2 mRNA.

    Science.gov (United States)

    Kuwano, Y; Nishida, K; Kajita, K; Satake, Y; Akaike, Y; Fujita, K; Kano, S; Masuda, K; Rokutan, K

    2015-05-01

    RNA-binding proteins and microRNAs are potent post-transcriptional regulators of gene expression. Human transformer 2β (Tra2β) is a serine/arginine-rich-like protein splicing factor and is now implicated to have wide-ranging roles in gene expression as an RNA-binding protein. RNA immunoprecipitation (RIP) with an anti-Tra2β antibody and microarray analysis identified a subset of Tra2β-associated mRNAs in HCT116 human colon cancer cells, many of which encoded cell death-related proteins including Bcl-2 (B-cell CLL/lymphoma 2). Tra2β knockdown in HCT116 cells decreased Bcl-2 expression and induced apoptosis. Tra2β knockdown accelerated the decay of BCL2α mRNA that encodes Bcl-2 and full-length 3' UTR, while it did not affect the stability of BCL2β mRNA having a short, alternatively spliced 3' UTR different from BCL2α 3' UTR. RIP assays with anti-Tra2β and anti-Argonaute 2 antibodies, respectively, showed that Tra2β bound to BCL2α 3' UTR, and that Tra2β knockdown facilitated association of miR-204 with BCL2α 3' UTR. The consensus sequence (GAA) for Tra2β-binding lies within the miR-204-binding site of BCL2 3' UTR. Mutation of the consensus sequence canceled the binding of Tra2β to BCL2 3' UTR without disrupting miR-204-binding to BCL2 3' UTR. Transfection of an anti-miR-204 or introduction of three-point mutations into the miR-204-binding site increased BCL2 mRNA and Bcl-2 protein levels. Inversely, transfection of precursor miR-204 reduced their levels. Experiments with Tra2β-silenced or overexpressed cells revealed that Tra2β antagonized the effects of miR-204 and upregulated Bcl-2 expression. Furthermore, TRA2β mRNA expression was significantly upregulated in 22 colon cancer tissues compared with paired normal tissues and positively correlated with BCL2 mRNA expression. Tra2β knockdown in human lung adenocarcinoma cells (A549) increased their sensitivity to anticancer drugs. Taken together, our findings suggest that Tra2β regulates apoptosis by

  16. Differential expression of Bcl-2 and Bax during gastric ischemia-reperfusion of rats

    Institute of Scientific and Technical Information of China (English)

    Wei-Li Qiao; Guang-Ming Wang; Yue Shi; Jin-Xia Wu; You-Jian Qi; Jian-Fu Zhang; Hong Sun; Chang-Dong Yan

    2011-01-01

    AIM: To investigate expression of Bcl-2 and Bax in gastric ischemia-reperfusion (GI-R) and involvement of extracellular signal-regulated kinase (ERK) 1/2 activation.METHODS: The GI-R model was established by ligature of the celiac artery for 30 min and reperfusion in Sprague-Dawley rats. Rats were assigned to groups in accordancewith their evaluation period: control, 0, 0.5, 1, 3, 6, 24,48, and 72 h. Expression and distribution of Bcl-2 and Bax proteins were analyzed by immunohistochemistry and western blotting in gastric tissue samples after sacrifice.RESULTS: Compared with controls, the percentage of positive cells and protein levels of Bcl-2 decreased in the early phases of reperfusion, reached its minimumat 1 h (P < 0.05); it then increased, reaching its peak at 24 h of reperfusion (P < 0.05). The pattern of Bax expression was opposite to that of Bcl-2. Bax expressionincreased after reperfusion, with its peak at 1 h of reperfusion (P < 0.05), and then it decreased gradually to a minimum at 24 h after reperfusion (P < 0.05).On the other hand, inhibition of activation of ERK1/2 induced by PD98059, a specific upstream MEK inhibitor,had significant effects on Bcl-2 and Bax in GI-R.Compared with GI-R treatment only at 3 h of reperfusion,PD98059 reduced the number of Bcl-2 positive cells (0.58% of R3h group, P < 0.05) and Bcl-2 proteinlevel (74% of R3h group, P < 0.05) but increased the number of Bax-positive cells (1.33-fold vs R3h group, P< 0.05) and Bax protein level (1.35-fold of R3h group,P < 0.05).CONCLUSION: These results indicated that the Bcl-2 and Bax played a pivotal role in the gastric mucosal I-R injury and repair by activation of ERK1/2.

  17. Anti-apoptotic effects of aspirin following cerebral ischemia-reperfusion injury in rats

    Institute of Scientific and Technical Information of China (English)

    Liying Qiu; Bin Du; Ying Li; Hongbin Fan; Zhiyong Yang

    2008-01-01

    /kg aspirin decreased MDA content and increased ATP levels. However, 6 mg/kg aspirin did not have the same effect. CONCLUSION: Aspirin reduced the number of apoptotic cells following CIRI. These results suggest that the neuroprotective mechanism of aspirin could be related to elevated Bcl-2 protein levels or decreased Bax protein expression. The increase in the ratio of Bcl-2 to Bax appears to be a common anti-apoptotic mechanism of aspirin.

  18. Genomic alterations in BCL2L1 and DLC1 contribute to drug sensitivity in gastric cancer.

    Science.gov (United States)

    Park, Hansoo; Cho, Sung-Yup; Kim, Hyerim; Na, Deukchae; Han, Jee Yun; Chae, Jeesoo; Park, Changho; Park, Ok-Kyoung; Min, Seoyeon; Kang, Jinjoo; Choi, Boram; Min, Jimin; Kwon, Jee Young; Suh, Yun-Suhk; Kong, Seong-Ho; Lee, Hyuk-Joon; Liu, Edison T; Kim, Jong-Il; Kim, Sunghoon; Yang, Han-Kwang; Lee, Charles

    2015-10-01

    Gastric cancer (GC) is the third leading cause of cancer-related deaths worldwide. Recent high-throughput analyses of genomic alterations revealed several driver genes and altered pathways in GC. However, therapeutic applications from genomic data are limited, largely as a result of the lack of druggable molecular targets and preclinical models for drug selection. To identify new therapeutic targets for GC, we performed array comparative genomic hybridization (aCGH) of DNA from 103 patients with GC for copy number alteration (CNA) analysis, and whole-exome sequencing from 55 GCs from the same patients for mutation profiling. Pathway analysis showed recurrent alterations in the Wnt signaling [APC, CTNNB1, and DLC1 (deleted in liver cancer 1)], ErbB signaling (ERBB2, PIK3CA, and KRAS), and p53 signaling/apoptosis [TP53 and BCL2L1 (BCL2-like 1)] pathways. In 18.4% of GC cases (19/103), amplification of the antiapoptotic gene BCL2L1 was observed, and subsequently a BCL2L1 inhibitor was shown to markedly decrease cell viability in BCL2L1-amplified cell lines and in similarly altered patient-derived GC xenografts, especially when combined with other chemotherapeutic agents. In 10.9% of cases (6/55), mutations in DLC1 were found and were also shown to confer a growth advantage for these cells via activation of Rho-ROCK signaling, rendering these cells more susceptible to a ROCK inhibitor. Taken together, our study implicates BCL2L1 and DLC1 as potential druggable targets for specific subsets of GC cases. PMID:26401016

  19. Simultaneous gene silencing of Bcl-2, XIAP and Survivin re-sensitizes pancreatic cancer cells towards apoptosis

    International Nuclear Information System (INIS)

    Pancreatic ductal adenocarcinoma shows a distinct apoptosis resistance, which contributes significantly to the aggressive nature of this tumor and constrains the effectiveness of new therapeutic strategies. Apoptosis resistance is determined by the net balance of the cells pro-and anti-apoptotic 'control mechanisms'. Numerous dysregulated anti-apoptotic genes have been identified in pancreatic cancer and seem to contribute to the high anti-apoptotic buffering capacity. We aimed to compare the benefit of simultaneous gene silencing (SGS) of several candidate genes with conventional gene silencing of single genes. From literature search we identified the anti-apoptotic genes XIAP, Survivin and Bcl-2 as commonly upregulated in pancreatic cancer. We performed SGS and silencing of single candidate genes using siRNA molecules in two pancreatic cancer cell lines. Effectiveness of SGS was assessed by qRT-PCR and western blotting. Apoptosis induction was measured by flow cytometry and caspase activation. Simultaneous gene silencing reduced expression of the three target genes effectively. Compared to silencing of a single target or control, SGS of these genes resulted in a significant higher induction of apoptosis in pancreatic cancer cells. In the present study we performed a subliminal silencing of different anti-apoptotic target genes simultaneously. Compared to silencing of single target genes, SGS had a significant higher impact on apoptosis induction in pancreatic cancer cells. Thereby, we give further evidence for the concept of an anti-apoptotic buffering capacity of pancreatic cancer cells

  20. miR-204 targets Bcl-2 expression and enhances responsiveness of gastric cancer

    Science.gov (United States)

    Sacconi, A; Biagioni, F; Canu, V; Mori, F; Di Benedetto, A; Lorenzon, L; Ercolani, C; Di Agostino, S; Cambria, A M; Germoni, S; Grasso, G; Blandino, R; Panebianco, V; Ziparo, V; Federici, O; Muti, P; Strano, S; Carboni, F; Mottolese, M; Diodoro, M; Pescarmona, E; Garofalo, A; Blandino, G

    2012-01-01

    Micro RNAs (miRs) are small non-coding RNAs aberrantly expressed in human tumors. Here, we aim to identify miRs whose deregulated expression leads to the activation of oncogenic pathways in human gastric cancers (GCs). Thirty nine out of 123 tumoral and matched uninvolved peritumoral gastric specimens from three independent European subsets of patients were analyzed for the expression of 851 human miRs using Agilent Platform. The remaining 84 samples were used to validate miRs differentially expressed between tumoral and matched peritumoral specimens by qPCR. miR-204 falls into a group of eight miRs differentially expressed between tumoral and peritumoral samples. Downregulation of miR-204 has prognostic value and correlates with increased staining of Bcl-2 protein in tumoral specimens. Ectopic expression of miR-204 inhibited colony forming ability, migration and tumor engraftment of GC cells. miR-204 targeted Bcl-2 messenger RNA and increased responsiveness of GC cells to 5-fluorouracil and oxaliplatin treatment. Ectopic expression of Bcl-2 protein counteracted miR-204 pro-apoptotic activity in response to 5-fluorouracil. Altogether, these findings suggest that modulation of aberrant expression of miR-204, which in turn releases oncogenic Bcl-2 protein activity might hold promise for preventive and therapeutic strategies of GC. PMID:23152059

  1. Apoptosis-related protein expression in rabbits with blast brain injury following early hyperbaric oxygen therapy

    Institute of Scientific and Technical Information of China (English)

    Shaonian Xu; Jiachuan Liu; Yongming Zhang; Chunlin Wang; Jinbiao Wang; Yanyan Yang; Jian Huo; Wenjiang Sun

    2012-01-01

    We treated detonator-explosion-induced craniocerebral injury in rabbits with hyperbaric oxygen 1-24 hours post-injury. Expression of the apoptosis-regulating protein cytochrome c, the pro-apoptotic protein Bax and the apoptosis marker caspase-3 in the tissues surrounding the area of injury was significantly reduced, while that of the anti-apoptotic protein Bcl-2 was significantly increased. Our findings indicate that the curative effects of early hyperbaric oxygen on cortical cell apoptosis is associated with suppression of cytochrome c release from mitochondria. This mechanism underlies the observed reduction in Bax expression and upregulation of Bcl-2 expression.

  2. Therapeutic Modulation of Apoptosis: Targeting the BCL-2 Family at the Interface of the Mitochondrial Membrane

    Science.gov (United States)

    Nemec, Kathleen N.

    2008-01-01

    A vast portion of human disease results when the process of apoptosis is defective. Disorders resulting from inappropriate cell death range from autoimmune and neurodegenerative conditions to heart disease. Conversely, prevention of apoptosis is the hallmark of cancer and confounds the efficacy of cancer therapeutics. In the search for optimal targets that would enable the control of apoptosis, members of the BCL-2 family of anti- and pro-apoptotic factors have figured prominently. Development of BCL-2 antisense approaches, small molecules, and BH3 peptidomimetics has met with both success and failure. Success-because BCL-2 proteins play essential roles in apoptosis. Failure-because single targets for drug development have limited scope. By examining the activity of the BCL-2 proteins in relation to the mitochondrial landscape and drawing attention to the significant mitochondrial membrane alterations that ensue during apoptosis, we demonstrate the need for a broader based multi-disciplinary approach for the design of novel apoptosis-modulating compounds in the treatment of human disease. PMID:18972587

  3. Herpesvirus pan encodes a functional homologue of BHRF1, the Epstein-Barr virus v-Bcl-2

    Directory of Open Access Journals (Sweden)

    Williams Tracey

    2005-02-01

    Full Text Available Abstract Background Epstein-Barr virus (EBV latently infects about 90% of the human population and is associated with benign and malignant diseases of lymphoid and epithelial origin. BHRF1, an early lytic cycle antigen, is an apoptosis suppressing member of the Bcl-2 family. In vitro studies imply that BHRF1 is dispensable for both virus replication and transformation. However, the fact that BHRF1 is highly conserved not only in all EBV isolates studied to date but also in the analogous viruses Herpesvirus papio and Herpesvirus pan that infect baboons and chimpanzees respectively, suggests BHRF1 may play an important role in vivo. Results Herpesvirus papio BHRF1 has been shown to function in an analogous manner to EBV BHRF1 in response to DNA damaging agents in human keratinocytes. In this study we show that the heterologous expression of the previously uncharacterised Herpesvirus pan BHRF1 in the human Burkitt's lymphoma cell line Ramos-BL provides similar anti-apoptotic functions to that of EBV BHRF1 in response to apoptosis triggered by serum withdrawal, etoposide treatment and ultraviolet (UV radiation. We also map the amino acid changes onto the recently solved structure of the EBV BHRF1 and reveal that these changes are unlikely to alter the 3D structure of the protein. Conclusions These findings show that the functional conservation of BHRF1 extends to a lymphoid background, suggesting that the primate virus proteins interact with cellular proteins that are themselves highly conserved across the higher primates. Further weight is added to this suggestion when we show that the difference in amino acid sequences map to regions on the 3D structure of EBV BHRF1 that are unlikely to change the conformation of the protein.

  4. The Influence of Matrine on Apoptosis and Expression of Bax and Bci-2 in Colorectal Cancer Cells%苦参碱对大肠癌细胞凋亡及Bax、Bcl-2表达的影响

    Institute of Scientific and Technical Information of China (English)

    王雷; 刘明

    2012-01-01

    [Purpose] To investigate the effect of Matrine on proliferation inhibition, apoptotic and Bax and Bcl-2 expression in human colorectal cancer cell line Lovo. [Methods] Lovo cells cultured in vitro were interfered with 0.05-1.6mg/ml different concentration of Matrine. The proliferation inhibition effect on Lovo cells was observed by MTT method. Apoptosis induction effect on Lovo cells was detected by DNA ladder, flow cytometer and TUNEL staining. The expression of Bcl-2 and Bax proteins correlated with apoptosis were detected by Western Blot assay. [Results] After being exposed to Matrine (0.05-1.6mg/ml) for 24 and 48h, the proliferation of Lovo cells was inhibited in a dose-time dependent manner. DNA ladder, Annexin V-PI method and TUNEL staining showed Matrine was obviously increased along with Matrine concentration increased. The expression of pro-apoptotic protein Bax was increased, while anti-apoptotic protein Bcl-2 was decreased as Matrine doses increased. [Conclusion] Matrine can inhibit proliferation and induction of apoptosis in colorectal cancer cells. Increased expression of Bax and decreased expression of Bcl-2 might involve in Matrine-induced apoptosis.%[目的]探讨苦参碱对人大肠癌Lovo细胞增殖抑制和凋亡诱导作用及其对Bax、Bcl-2表达的影响.[方法] 0.05~l.6mg/ml不同浓度苦参碱作用Lovo细胞,采用MTT法检测苦参碱对大肠癌Lovo细胞增殖抑制作用,DNA ladder、AnnexinV -PI法及TUNEL染色检测细胞凋亡,Western Blot法检测凋亡相关蛋白Bax、Bcl-2表达的变化.[结果]0.05~1.6mg/ml苦参碱处理Lovo细胞24h或48h后,细胞增殖均明显受抑制;DNA ladder、Annexin V-PI法及TUNEL染色检测结果显示苦参碱呈时间、剂量依赖性诱导细胞凋亡;促凋亡蛋白Bax随着苦参碱剂量增加表达增加,抗凋亡蛋白Bcl-2随着苦参碱剂量增加表达减少.[结论]苦参碱具有抑制大肠癌细胞增殖,诱导其凋亡的作用.苦参碱诱导大肠癌细胞凋

  5. Combined transfection of Bcl-2 siRNA and miR-15a oligonucleotides enhanced methotrexate-induced apoptosis in Raji cells

    International Nuclear Information System (INIS)

    B-cell lymphoma 2 (Bcl-2) is an important member of the Bcl-2 family of proteins that regulate the induction of apoptosis. This study aims to investigate whether Bcl-2 small interfering RNA (siRNA) combined with miR-15a oligonucleotides (ODN) could enhance methotrexate (MTX)-induced apoptosis in Raji cells. Chemically synthesized miR-15a ODN and Bcl-2 siRNA were transfected in Raji cells by using a HiPerFect Transfection Reagent and then combined with MTX. Expression levels of Bcl-2 protein were detected by Western blot. Cell proliferation was determined by CCK8 assay. The rate of cell apoptosis was determined by Annexin V/PI double staining. The morphology of apoptotic cells was observed by Hoechst-33 258 staining. After the cells were transfected with miR-15a ODN combined with Bcl-2 siRNA, Bcl-2 protein levels were evidently decreased. CCK8 assay showed that cell proliferation was significantly decreased and was significantly lower in miR-15a ODN combined with Bcl-2 siRNA plus MTX group than in miR-15a ODN with methotrexate group, Bcl-2 siRNA with MTX group, and single MTX group (P<0.05). Hoechst 33258 staining revealed numerous apoptotic cells. AnnexinV/PI double staining showed that the apoptotic rates were (13.13±1.60)%, (34.47±2.96)%, (32.87±3.48)%, and (45.47±2.16)% in MTX, Bcl-2 siRNA plus MTX, miR-15a ODN plus MTX, and miR-15a ODN combined with Bcl-2 siRNA plus MTX groups, respectively. Among these groups, the apoptotic rate of miR-15a ODN combined with Bcl-2 siRNA plus MTX group was the highest; this apoptotic rate was also significantly different from that of miR-15a ODN or Bcl-2 siRNA plus MTX (P<0.05). Bcl-2 siRNA combined with miR-15a ODN could enhance MTX-induced apoptosis in Raji cells. Bcl-2 siRNA and miR-15a combined with MTX may be a useful approach to improve the treatment effects on lymphoma

  6. Statins, Bcl-2 and Apoptosis: Cell Death or Cell Protection?

    OpenAIRE

    Wood, W. Gibson; Igbavboa, Urule; Muller, Walter E.; Gunter P. Eckert

    2013-01-01

    Statins have proven their effectiveness in the treatment of cardiovascular disease. This class of drugs has also attracted attention as a potential treatment for dissimilar diseases such as certain types of cancers and neurodegenerative diseases. What appears to be a contradiction is that in the case of cancer, it has been suggested that statins increase apoptosis and alter levels of Bcl-2 family members (e.g., reduce Bcl-2 and increase Bax) whereas, studies mainly using non-cancerous cells r...

  7. Phenylboronic acid-functionalized polyamidoamine-mediated Bcl-2 siRNA delivery for inhibiting the cell proliferation.

    Science.gov (United States)

    Wu, Di; Yang, Jiebing; Xing, Zhen; Han, Haobo; Wang, Tingting; Zhang, Aijun; Yang, Yan; Li, Quanshun

    2016-10-01

    In this study, the conjugation of phenylboronic acid (PBA) to amine-terminated polyamidoamine (PAMAM) was successfully conducted to prepare a tumor-targeted gene carrier PBA-functionalized PAMAM (PPP) for Bcl-2 siRNA delivery, using a heterobifunctional crosslinker NHS-PEG5k-Mal. The carrier possessed favorable capacity for siRNA condensation and could protect siRNA from the degradation against RNase and serum. The introduction of PBA could facilitate the cellular uptake and further transfection of Bcl-2 siRNA demonstrated by confocal laser scanning microscopy and flow cytometry. Meanwhile, PPP-mediated transfection of Bcl-2 siRNA could significantly inhibit the expression of Bcl-2 gene at both mRNA and protein levels. Furthermore, owing to the knock-down of Bcl-2, PPP/siRNA could significantly inhibit the cell proliferation by inducing the cell apoptosis, and also enhance the antitumor efficiency of doxorubicin by suppressing the resistance of tumor cells to chemotherapeutics. In conclusion, the PPP-mediated Bcl-2 siRNA delivery could potentially be an effective platform for solving the drug resistance and further achieving the combined chemotherapy and gene therapy in tumor treatment. PMID:27371891

  8. 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.

  9. Effects of Caspase proteins and Bcl-2 protein of osteoblasts on pathogenesis of postmenopausal osteoporosis%成骨细胞中 Caspase 蛋白和 Bcl-2蛋白在绝经后骨质疏松症发病机理中的作用

    Institute of Scientific and Technical Information of China (English)

    刘嘉眉; 李颖

    2015-01-01

    Objective To investigate the effects of Caspase-3, Caspase-9, B-cell lymphoma-2 ( Bcl-2) protein in the pathogenesis of postmenopausal osteoporosis.Methods From January 2012 to December 2012, 20 cases of hip replacement surgery in the First Affiliated Hospital of Guangzhou Medical University were enrolled.All the patients who were female and in menopause period were divided into the osteoporosis group ( n=10) and the control group ( n=10) .The cancellous bones in the femoral head and femoral neck were collected during the hip replacement and were used to culture osteoblasts.Caspase-3, Caspase-9 and Bcl-2 were examined using enzyme-linked immunosorbent assay ( ELISA) .Two independent samples were compared using t test, if variance unequal, the samples were compared by rank-sum test. Results Compared with the control group, the expression levels of Caspase-3 and Caspase-9 increased and the expression level of Bcl-2 obviously decreased in the osteoporosis group [Caspase-3 (11.0 ±1.5) pmol/L, Caspase-9 (10.9 ±1.7) pmol/L, Bcl-2(1.3 ±0.5) ng/ml];the differences between the two groups were statistically significant ( Caspase-3:t=5.76, P<0.05;Caspase-9:t=4.47, P<0.05; Bcl-2: t=2.43, P<0.05).Conclusion In the process of osteoblast apoptosis in osteoporosis, Caspases-dependent apoptotic pathways may be activated, and the Bcl-2 way is restrained, which may be involved in the pathogenesis of the postmenopausal osteoporosis.%目的:探讨半胱氨酸天冬氨酸蛋白酶(Caspase)-3、Caspase-9、B细胞淋巴瘤-2(Bcl-2)蛋白对绝经后骨质疏松症发病机理的影响。方法2012年1月至2012年12月期间收集广州医科大学附属第一医院老年病科住院的需行髋关节置换手术的女性绝经期患者20例,分为骨质疏松症组与对照组,每组各10例。术中取下股骨头或股骨颈中松质骨,分别进行成骨细胞的体外培养,通过酶联免疫吸附试验( ELISA)方法检测

  10. Effects of Radix notoginseng extracts drug-containing serum on expressions of bcl-2, Bax and p21WAF1 proteins in MNNG transformed GES-1 cells%三七提取物含药血清对MNNG转化后GES-1细胞凋亡相关基因蛋白表达的影响

    Institute of Scientific and Technical Information of China (English)

    李军祥; 王志斌; 朱陵群; 牛福玲; 崔巍

    2008-01-01

    Objective: To investigate the effects of Radix notoginseng extracts drug-containing serum on the expressions of apoptosis-regulating proteins including Bax, bcl-2 and p21WAF1 in precancerous gastric cells. Methods: The N-methyI-N'-nitro-N-nitroso-guanidine (MNNG) transformed eternalized human gastric mucosa epithelium GES-I cell line (MC cell) was used in vitro as a model of gastric precancerous lesion. The medicated canine serum was prepared by feeding to the adult Beagle dog with Radix notoginseng extracts and obtaining the serum after 2-hour medication. MC cells were cultured with medicated canine serum (medicated serum group) or non-medicated canine serum (normal control group) for 72 hours. Expressions of Bax, bcl-2 and p21WAF1 proteins were detected by immunocytochemical assay and the average optical density of the cells was determined by an image analysis system. Results. Compared with those of the normal control group, Bax and p21WAF1 expressions in medicated serum group were significantly enhanced (P<0.01), while the expression of bcl-2 was significantly reduced (P 001). Conclusion. Radix notoginseng extracts may inhibit the proliferation and promote the apoptosis of precancerous gastric cells through altering expressions of the bcl-2, Bax and p21WAF1 genes.%目的:研究三七提取物犬药物血清作用于胃癌前细胞后,其凋亡相关基因蛋白表达的变化.方法:采用被N-甲基-N-硝基-N-亚硝基胍(N-methyl-N-nitroso-guanidine,MNNG)转化后的永生化人胃黏膜上皮细胞系GES-1细胞(简称MC细胞)作为胃癌前病变细胞的体外研究模型,用三七提取物一次性灌胃彼格犬,取给药后2 h的血清作为实验药物血清.以免疫组织化学法检测药物血清对MC细胞作用72 h后bcl-2、Bax和p21WAF13种凋亡相关基因蛋白表达情况,并与正常培养的MC细胞相比较.结果:药物血清作用后的MC细胞中Bax和p21WAF1的表达较正常培养的MC细胞升高(P<0.01);Bc1-2表达较

  11. Influence of neurotrophin-3 on Bcl-2 and Bax expressions in spinal cord injury of rats

    Institute of Scientific and Technical Information of China (English)

    GUO Shu-zhang; JIANG Tao; REN Xian-jun

    2007-01-01

    Objective:To study the protective mechanisms of neurotrophin-3 (NT-3) on the spinal cord injury.Methods:Totally 105 SD rats were randomly divided into 3 groups:control group,experimental group and sham operation group.Rats from the former 2 groups were inflicted to animal model of acute spinal cord injury according to Allen's (WD) by situating a thin plastic tube in the subarachnoid space below the injury level for perfusion.Rats in experimental group received 20μl NT-3 (200 ng) from the tube at 0,4,8,12,24 h and 3,7 d after injury,and those in control group got an equal volume of normal saline at the same time.The animals in sham operation group only received opening vertebral plate and tube was put in subarachnoid space.The rats were sacrificed at 4,8,12,24 h and 3,7,14 d post injury (n=5).The expression levels of Bcl-2 and Bax proteins in spinal cord of rats were detected by immunohistochemistry assay.Results:The level of Bax protein in control group significantly increased as compared with those in sham operation group, and the peak reached at 8 h after spinal cord injury.The Bcl-2 proteins were always weakly positive.The Bax proteins in NT-3 group significantly decreased but the Bcl-2 proteins obviously increased as compared with those in control group.Conclusion:NT-3 can protect spinal cord from injury in vivo.One of the mechanisms is that NT-3 can inhibit abnormal expression of Bax protein,and increase the expression of Bcl-2 protein,then inhibit apoptosis after spinal cord injury.

  12. Tissue factor/FVIIa activates Bcl-2 and prevents doxorubicin-induced apoptosis in neuroblastoma cells

    International Nuclear Information System (INIS)

    Tissue factor (TF) is a transmembrane protein that acts as a receptor for activated coagulation factor VII (FVIIa), initiating the coagulation cascade. Recent studies demonstrate that expression of tumor-derived TF also mediates intracellular signaling relevant to tumor growth and apoptosis. Our present study investigates the possible mechanism by which the interaction between TF and FVIIa regulates chemotherapy resistance in neuroblastoma cell lines. Gene and siRNA transfection was used to enforce TF expression in a TF-negative neuroblastoma cell line and to silence endogenous TF expression in a TF-overexpressing neuroblastoma line, respectively. The expression of TF, Bcl-2, STAT5, and Akt as well as the phosphorylation of STAT5 and Akt in gene transfected cells or cells treated with JAK inhibitor and LY294002 were determined by Western blot assay. Tumor cell growth was determined by a clonogenic assay. Cytotoxic and apoptotic effect of doxorubicin on neuroblastoma cell lines was analyzed by WST assay and annexin-V staining (by flow cytometry) respectively. Enforced expression of TF in a TF-negative neuroblastoma cell line in the presence of FVIIa induced upregulation of Bcl-2, leading to resistance to doxorubicin. Conversely, inhibition of endogenous TF expression in a TF-overexpressing neuroblastoma cell line using siRNA resulted in down-regulation of Bcl-2 and sensitization to doxorubicin-induced apoptosis. Additionally, neuroblastoma cells expressing high levels of either endogenous or transfected TF treated with FVIIa readily phosphorylated STAT5 and Akt. Using selective pharmacologic inhibitors, we demonstrated that JAK inhibitor I, but not the PI3K inhibitor LY294002, blocked the TF/FVIIa-induced upregulation of Bcl-2. This study shows that in neuroblastoma cell lines overexpressed TF ligated with FVIIa produced upregulation of Bcl-2 expression through the JAK/STAT5 signaling pathway, resulting in resistance to apoptosis. We surmise that this TF

  13. 雌激素对大鼠胸腺细胞凋亡及Bcl-2、Bax表达的影响%Effects of estrogen on apoptosis and expression of Bcl-2 and Bax in rat thymus

    Institute of Scientific and Technical Information of China (English)

    李雅娜; 孙研; 崔春红; 殷彦君

    2011-01-01

    thymus in the groups treated with estradiol benzoate. The expression of Bcl-2 protein in rats injected with estradiol benzoate was lower than that in the control group, and Bax was higher. The expression of Bcl-2 mRNA and Bax mRNA in the thymus showed consistency with the expression of Bcl-2 and Bax. Conclusion: Estradiol benzoate may increase mass index of thymus, accelerate the degradation of the thymus, induce the apoptosis of the thymus, restrain the expression of Bcl-2 protein and promote the expression of Bax protein in the thymus of rats.

  14. 14-3-3 proteins in apoptosis

    Directory of Open Access Journals (Sweden)

    M. Rosenquist

    2003-04-01

    Full Text Available The once obscure members of the 14-3-3 protein family play significant roles in the determination of cell fate. By inhibiting the pro-apoptotic BAD (Bcl-2-antagonist of cell death and the transcription factor FKHRL-1, 14-3-3 displays important anti-apoptotic characteristics. To date, five points of interaction of 14-3-3 with the apoptotic machinery have been identified. How these interactions are regulated still remains a mystery.

  15. Effect of Achyranthes bidentata polysaccharides on the expression of BCL-2 and bax in hepatic tissues after exhaustive exercise in rats.

    Science.gov (United States)

    Lin, Jinyang; Zhang, Zhuoying; Shan, Ying

    2010-01-01

    This study aims to assess the effects of Achyranthes bidentata polysaccharides (ABPS) on the expression of bcl-2 and bax in hepatic tissues after exhaustive exercise in order to provide theoretical support for the application of ABPS in the field of sports nutrition. Thirty male Sprague-Dawley rats were randomized into three groups, each consisting of 10 rats: Normal control group (NCG), Exhausting exercises control group (EECG), ABPS treated group (ATG). ABPS were fed orally by gastric intubation to rats of ABPS treated group (ATG) once daily for 7 days. Control animals (EECG and NCG) received the same amount of isotonic sodium chloride solution. Exhaustive exercise was performed on a rodent treadmill. The SP (streptavidin peroxidase) method for immunohistochemical staining was adopted to test the protein expression of bax and bcl-2 in the hepatic tissues of the rats. Exhausting exercises increased bax protein expression of hepatic tissues of rats and bax/bcl-2 ratio dramatically, but a decreased bcl-2 protein expression. In the rats fed ABPS orally by gastric intubation, the bax protein expression and bax/bcl-2 ratio obviously decreased, while bcl-2 protein expression increased. The result indicated that bax and bcl-2 co-regulated the exercise-induced hepatocyte apoptosis. Feeding ABPS orally by gastric intubation to rats can inhibit the hepatocyte apoptosis in exhaustive exercise. PMID:21731162

  16. Histone deacetylase inhibitors strongly sensitise neuroblastoma cells to TRAIL-induced apoptosis by a caspases-dependent increase of the pro- to anti-apoptotic proteins ratio

    International Nuclear Information System (INIS)

    Neuroblastoma (NB) is the second most common solid childhood tumour, an aggressive disease for which new therapeutic strategies are strongly needed. Tumour necrosis factor-related apoptosis-inducing ligand (TRAIL) selectively induces apoptosis in most tumour cells, but not in normal tissues and therefore represents a valuable candidate in apoptosis-inducing therapies. Caspase-8 is silenced in a subset of highly malignant NB cells, which results in full TRAIL resistance. In addition, despite constitutive caspase-8 expression, or its possible restoration by different strategies, NB cells remain weakly sensitive to TRAIL indicating a need to develop strategies to sensitise NB cells to TRAIL. Histone deacetylase inhibitors (HDACIs) are a new class of anti-cancer agent inducing apoptosis or cell cycle arrest in tumour cells with very low toxicity toward normal cells. Although HDACIs were recently shown to increase death induced by TRAIL in weakly TRAIL-sensitive tumour cells, the precise involved sensitisation mechanisms have not been fully identified. NB cell lines were treated with various doses of HDACIs and TRAIL, then cytotoxicity was analysed by MTS/PMS proliferation assays, apoptosis was measured by the Propidium staining method, caspases activity by colorimetric protease assays, and (in)activation of apoptotic proteins by immunoblotting. Sub-toxic doses of HDACIs strongly sensitised caspase-8 positive NB cell lines to TRAIL induced apoptosis in a caspases dependent manner. Combined treatments increased the activation of caspases and Bid, and the inactivation of the anti-apoptotic proteins XIAP, Bcl-x, RIP, and survivin, thereby increasing the pro- to anti-apoptotic protein ratio. It also enhanced the activation of the mitochondrial pathway. Interestingly, the kinetics of caspases activation and inactivation of anti-apoptotic proteins is accelerated by combined treatment with TRAIL and HDACIs compared to TRAIL alone. In contrast, cell surface expression of TRAIL

  17. Study of Bcl-2 siRNA Enhancement of Sensitivity of HL-60 Cells to All Trans Retinoic Acid

    Institute of Scientific and Technical Information of China (English)

    Haiyan Hu; Yuan Zhang; Dongmei He

    2008-01-01

    OBJECTIVE To study whether siRNA targeting against the Bcl-2gene can enhance sensitivity of HL-60 cells to all trans retinoic acid (ATRA).METHODS siRNA, which is a leading sequence selected by previous experiments, was transferred into HL-60 cells. At 6 h after transfection, the cells were cultured with ATRA. The cell growth of the HL-60 cells was measured by the MTT assay at 24,48, 72 h. The level of the Bcl-2 protein and ROS (reactive oxygen species) as well as membrane potential of the mitochondria were determined by flowcytometry.RESULTS siRNA significantly increased the inhibitory effect of ATRA on growth of the HL-60 cells. The combination of siRNA with ATRA resulted in a decrease in the Bcl-2 protein level and an increase in the ROS level as well as significantly lowering the mitochondrial membrane potential of the HL-60 cells (P < 0.05).CONCLUSION Effective siRNA targeting of Bcl-2 increases the sensitivity of HL-60 leukemic cells to ATRA by inhibiting the expression of the Bcl-2 protein.

  18. 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

    2016-01-01

    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. PMID:27601896

  19. Darbepoetin alpha, a long-acting erythropoeitin derivate, does not alter LPS evoked myocardial depression and gene expression of Bax, Bcl-Xs, Bcl-XL, Bcl-2, and TNF-alpha.

    Science.gov (United States)

    Brendt, Peter; Frey, Ulrich; Adamzik, Michael; Schäfer, Simon T; Peters, Jürgen

    2009-01-01

    Darbepoetin alpha (DA), a long-acting erythropoietin derivative stimulating erythropoiesis, can, by antiapoptotic effects, mitigate myocardial I/R injury. We tested the hypothesis that DA treatment improves left ventricular function (LV) in LPS evoked cardiomyopathy and alters gene expression of apoptosis-regulating proteins (Bcl-XL, Bcl-2, Bax, and Bcl-Xs) and TNF-alpha. In a prospective, controlled, randomized study in Lewis rats (n = 56; 8 groups), myocardial depression was evoked by LPS administration (serotype O127:B8; 10 mg/kg, i.p.). Darbepoetin alpha or vehicle was injected either 24 h before (pretreatment) or 2 h after LPS injection (treatment). Hearts were isolated 8 h after LPS injection, perfused (Krebs-Henseleit solution) in a Langendorff apparatus, and LV developed pressure and its derivatives were measured. For gene expression analysis, real-time polymerase chain reaction of LV specimen was performed. LPS decreased LV developed pressure (-64.6 +/- 7.9 mmHg) and its derivates by more than 60% in comparison to vehicle (P Xs, Bax, and TNF-alpha, but this was not altered by DA pretreatment. Furthermore, there was no effect on Bcl-Xl and Bcl-2 expression by DA alone. Whereas proapoptotic genes of the myocardium are up-regulated in LPS-induced cardiomyopathy, neither DA pretreatment nor treatment has significant effects on LV function or gene expression. This may suggest cardiac resistance to darbepoetin in LPS-mediated sepsis.

  20. 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

    2016-01-01

    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. PMID:27601896

  1. Meta-analysis confirms BCL2 is an independent prognostic marker in breast cancer

    International Nuclear Information System (INIS)

    A number of protein markers have been investigated as prognostic adjuncts in breast cancer but their translation into clinical practice has been impeded by a lack of appropriate validation. Recently, we showed that BCL2 protein expression had prognostic power independent of current used standards. Here, we present the results of a meta-analysis of the association between BCL2 expression and both disease free survival (DFS) and overall survival (OS) in female breast cancer. Reports published in 1994–2006 were selected for the meta-analysis using a search of PubMed. Studies that investigated the role of BCL2 expression by immunohistochemistry with a sample size greater than 100 were included. Seventeen papers reported the results of 18 different series including 5,892 cases with an average median follow-up of 92.1 months. Eight studies investigated DFS unadjusted for other variables in 2,285 cases. The relative hazard estimates ranged from 0.85 – 3.03 with a combined random effects estimate of 1.66 (95%CI 1.25 – 2.22). The effect of BCL2 on DFS adjusted for other prognostic factors was reported in 11 studies and the pooled random effects hazard ratio estimate was 1.58 (95%CI 1.29–1.94). OS was investigated unadjusted for other variables in eight studies incorporating 3,910 cases. The hazard estimates ranged from 0.99–4.31 with a pooled estimate of risk of 1.64 (95%CI 1.36–2.0). OS adjusted for other parameters was evaluated in nine series comprising 3,624 cases and the estimates for these studies ranged from 1.10 to 2.49 with a pooled estimate of 1.37 (95%CI 1.19–1.58). The meta-analysis strongly supports the prognostic role of BCL2 as assessed by immunohistochemistry in breast cancer and shows that this effect is independent of lymph node status, tumour size and tumour grade as well as a range of other biological variables on multi-variate analysis. Large prospective studies are now needed to establish the clinical utility of BCL2 as an independent

  2. Meta-analysis confirms BCL2 is an independent prognostic marker in breast cancer

    Directory of Open Access Journals (Sweden)

    Pharoah Paul DP

    2008-05-01

    Full Text Available Abstract Background A number of protein markers have been investigated as prognostic adjuncts in breast cancer but their translation into clinical practice has been impeded by a lack of appropriate validation. Recently, we showed that BCL2 protein expression had prognostic power independent of current used standards. Here, we present the results of a meta-analysis of the association between BCL2 expression and both disease free survival (DFS and overall survival (OS in female breast cancer. Methods Reports published in 1994–2006 were selected for the meta-analysis using a search of PubMed. Studies that investigated the role of BCL2 expression by immunohistochemistry with a sample size greater than 100 were included. Seventeen papers reported the results of 18 different series including 5,892 cases with an average median follow-up of 92.1 months. Results Eight studies investigated DFS unadjusted for other variables in 2,285 cases. The relative hazard estimates ranged from 0.85 – 3.03 with a combined random effects estimate of 1.66 (95%CI 1.25 – 2.22. The effect of BCL2 on DFS adjusted for other prognostic factors was reported in 11 studies and the pooled random effects hazard ratio estimate was 1.58 (95%CI 1.29–1.94. OS was investigated unadjusted for other variables in eight studies incorporating 3,910 cases. The hazard estimates ranged from 0.99–4.31 with a pooled estimate of risk of 1.64 (95%CI 1.36–2.0. OS adjusted for other parameters was evaluated in nine series comprising 3,624 cases and the estimates for these studies ranged from 1.10 to 2.49 with a pooled estimate of 1.37 (95%CI 1.19–1.58. Conclusion The meta-analysis strongly supports the prognostic role of BCL2 as assessed by immunohistochemistry in breast cancer and shows that this effect is independent of lymph node status, tumour size and tumour grade as well as a range of other biological variables on multi-variate analysis. Large prospective studies are now needed to

  3. Evaluation of Bcl-2 Family Gene Expression in Hippocampus of 3, 4-methylenedioxymethamphetamine Treated Rats

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    Hamed Hashemi-Nasl

    2012-01-01

    Full Text Available Objective: 3,4-methylenedioxymethamphetamine (MDMA is an illicit, recreational drugthat causes cellular death and neurotoxicity. This study evaluates the effects of differentdoses of MDMA on the expression of apoptosis–related proteins and genes in the hippocampusof adult rats.Materials and Methods: In this expremental study,a total of 20 male Sprague Dawley rats(200-250 g were treated with MDMA (0, 5, 10, 20 mg/kg i.p. twice daily for 7 days. Sevendays after the last administration of MDMA, the rats were killed. Bax and Bcl-2 genesin addition to protein expressions were detected by western blot and reverse transcriptionpolymerasechain reaction (RT-PCR.Results were analyzed using one-way ANOVA andp≤0.05 was considered statistically significant.Results: Our results showed that MDMA caused dose dependent up-regulation of Baxand down-regulation of Bcl-2 in the hippocampus. There was a significant alteration inbcl-2 and bax genes density.Conclusion: Changes in apoptosis-related proteins and respective genes relating to Baxand Bcl-2 might be involved in the molecular mechanism of MDMA-induced apoptosis.

  4. Ulipristal Acetate Inhibits Progesterone Receptor Isoform A-Mediated Human Breast Cancer Proliferation and BCl2-L1 Expression.

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    Esber, Nathalie; Le Billan, Florian; Resche-Rigon, Michèle; Loosfelt, Hugues; Lombès, Marc; Chabbert-Buffet, Nathalie

    2015-01-01

    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. PMID:26474308

  5. Ulipristal Acetate Inhibits Progesterone Receptor Isoform A-Mediated Human Breast Cancer Proliferation and BCl2-L1 Expression.

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    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.

  6. Inhibition of BCL-2 leads to increased apoptosis and delayed neuronal differentiation in human ReNcell VM cells in vitro.

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    Fröhlich, Michael; Jaeger, Alexandra; Weiss, Dieter G; Kriehuber, Ralf

    2016-02-01

    BCL-2 is a multifunctional protein involved in the regulation of apoptosis, cell cycle progression and neural developmental processes. Its function in the latter process is not well understood and needs further elucidation. Therefore, we characterized the protein expression kinetics of BCL-2 and associated regulatory proteins of the intrinsic apoptosis pathway during the process of neuronal differentiation in ReNcell VM cells with and without functional inhibition of BCL-2 by its competitive ligand HA14-1. Inhibition of BCL-2 caused a diminished BCL-2 expression and higher levels of cleaved BAX, activated Caspase-3 and cleaved PARP, all pro-apoptotic markers, when compared with untreated differentiating cells. In parallel, flow cytometric analysis of HA14-1-treated cells revealed a delayed differentiation into HuC/D+ neuronal cells when compared to untreated differentiating cells. In conclusion, BCL-2 possess a protective function in fully differentiated ReNcell VM cells. We propose that the pro-survival signaling of BCL-2 is closely connected with its stimulatory effects on neurogenesis of human neural progenitor cells.

  7. Expression of bcl-2 oncogene in gastric precancerous lesions and its correlation with syndromes in traditional Chinese medicine

    Institute of Scientific and Technical Information of China (English)

    Ling Hu; Shao-Xian Lao; Chun-Zhi Tang

    2005-01-01

    AIM: To observe the protein and mRNA expression of bcl-2 oncogene in gastric precancerous lesions (GPL) and to analyze its correlation with syndromes in traditional Chinese medicine (TCM).METHODS: Sixty-seven patients with GPL confirmed by gastroscopy and pathology were studied, including 39 cases of moderate gastric mucosal dysplasia, 19 casesof severe gastric mucosa dysplasia, g cases of incompletecolon metaplasia. In syndrome differentiation of TCM, 17 cases belonged to the syndrome of qi and yin deficiency of the spleen and stomach complicated by qi stagnation, 21 cases belonged to the syndrome of qi and yin deficiency of the spleen and stomach complicated by stomach heat, 29 cases belonged to the syndrome of qi and yin deficiency of the spleen and stomach complicated by blood stasis. Protein and mRNA expression of bcl-2 oncogene weredetected by labeled streptavidin biotin (LSAB) immunohistochemistry and in situ hybridization respectively. RESULTS: Abnormal expression of protein and mRNA on bcl-2 oncogene was found in GPL, which increased gradually with the course of lesions. In moderate and severe gastric mucosal dysplasia and incomplete colon metaplasia, there was no difference in the expression of bcl-2 oncogene (P>0.05). In different accompanying syndromes, the expression of protein and mRNA on bcl-2 oncogene increased gradually in the following order: deficiency of both qi and yin of the spleen and stomach accompanying qi stagnation → stomach heat → blood stasis. In GPL, compared with accompanying blood stasis, there was an obvious difference in the expression of bd-2 oncogene between the syndrome of qi and yin deficiency of the spleen and stomach and accompanying stomach heat, so did accompanying qi stagnation (the level of protein: χ2 = 8.45, P<0.05; the level of mRNA: χ2 = 7.35,P<0.05).CONCLUSION: Apoptosis-associated bcl-2 oncogene is abnormally expressed in GPL, which correlates with different accompanying syndromes in TCM.

  8. Prognostic significance of Bcl-2 in invasive mammary carcinomas: a comparative clinicopathologic study between "triple-negative" and non-"triple-negative" tumors.

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    Tawfik, Kareem; Kimler, Bruce F; Davis, Marilyn K; Fan, Fang; Tawfik, Ossama

    2012-01-01

    Bcl-2 is a tumorigenic protein that is expressed in 25% to 50% of breast cancers. Although its expression has been widely accepted as a favorable prognostic marker, its protective mechanism of action remains unclear. "Triple-negative" tumors are an aggressive subgroup known to carry a poor prognosis. Studies documenting prognostic significance of Bcl-2 expression in triple-negative in comparison to non-triple-negative breast cancers are limited. Bcl-2 expression was correlated with tumor size, grade, histologic type, lymphovascular invasion, lymph node status, patients' overall survival, estrogen receptor, progesterone receptor, Her-2, p53, and epidermal growth factor receptor in 124 triple-negative and 458 non-triple-negative tumors. There were significant differences between triple-negative and non-triple-negative tumors in their relationship to Bcl-2 expression (81% versus 29%, respectively) and tumor aggression. As previously reported, in non-triple-negative tumors, Bcl-2 positivity correlated with less aggressive tumors (94% of grade I tumors were Bcl-2+ versus 62% of grade III tumors, P < .011) and overall survival (P = .008). However, the opposite was true in patients with triple-negative tumors, where Bcl-2 positivity was associated with poorer survival (P = .64). In triple-negative tumors, Bcl-2 positivity was not associated with any of the aforementioned parameters except for a lower incidence of lymph node metastasis. Moreover, by Cox regression analysis of all variables, in patients with triple-negative tumors, lymphovascular invasion (P = .009) and Bcl-2 expression (P = .028) were predictors of poor survival. In conclusion, there are major clinicopathologic differences between breast cancer phenotypes. Our results establish the value of using Bcl-2 in prognostic stratification of patients and its potential therapeutic implications in selecting patients for treatment.

  9. EXPRESSION OF BAX AND BCL-2 IN MOUSE OFFSPRING BRAIN AFTER MATERNAL ORAL ADMINIS TRATION OF MONOSODIUM GLUTAMATE

    Institute of Scientific and Technical Information of China (English)

    徐磊; 赵晏; 展淑琴; 王会生; 史文春

    2002-01-01

    Objective To analyze the excitotoxicity of monoso dium glutamate (MSG) in the offspring cerebral cortex and hippocampal subregions after maternal oral administration of MSG. Methods Kunming mi ce were given per os MSG ( 4.0 g/kg ) at 17~21 days of pregnancy and their offs pring behaviors were studied at 10, 20 , 30 days postnatally. By using immunohis tochemical means, the involvement of Bcl-2 and Bax in the glutamate-induced c ell death in cortical and hippocampal neur ons were examined. Cell damage was assessed by direct cell counting. Res ults Administration of monosodium glutamate during the fetal period in mice resulted in a moderate increase in the expression of Bax in principal neuro ns in CA1, CA2, CA3, CA4 and in the cerebral cortex at postpartum 10, 20, 30 day s in the offspring mice, whereas Bcl-2 protein expressions were reduced signif icantly in the same regions as compared with those of controls. Conclusi on These findings suggest that glutamate toxicity results in cellular d eath via an apoptotic mechanism in which the Bcl-2/Bax-alpha molecular comple x may be involved. The glutamate-induced apoptosis appears to be related to the modulation of Bcl-2 family gene products such as Bcl-2 and Bax.

  10. Di-(2-ethylhexyl) phthalate induces apoptosis of GC-2spd cells via TR4/Bcl-2 pathway.

    Science.gov (United States)

    Zhu, Lishan; Lu, Jinchang; Tang, Xiao; Fu, Guoqing; Duan, Peng; Quan, Chao; Zhang, Ling; Zhang, Zhibing; Chang, Wei; Shi, Yuqin

    2016-06-01

    Di-(2-ethylhexyl) phthalate (DEHP) is a widely used environmental endocrine disruptor. Many studies have reported that DEHP exposure causes reproductive toxicity and cells apoptosis. However, the mechanism by which DEHP exposure causes male reproductive toxicity remains unknown. This study investigated the role of the testicular orphan nuclear receptor4 (TR4)/Bcl-2 pathway in apoptosis induced by DEHP, which resulted in reproductive damage. To elucidate the mechanism underpinning the male reproductive toxicity of DEHP, we sought to investigate apoptotic effects, expression levels of TR4/Bcl-2 pathway in GC-2spd cells, including TR4, Bcl-2 and caspase-3. GC-2spd cells were exposed to various concentrations of DEHP (0, 50, 100, or 200μM). The results indicated that, with the increase of the concentrations of DEHP, the survival rate of cell decreased gradually. DEHP exposure at over 100μM significantly induced apoptotic cell death. DEHP decreased SOD and GSH-Px activity in 200μM group. Compared to the control group, the mRNA levels of caspase-3 increased significantly, however, Bcl-2 mRNA decreased (PBcl-2 and procaspase-3 protein levels. Taken together, these results lead us to speculate that in vitro exposure to DEHP might induce apoptosis in GC-2spd cells through the TR4/Bcl-2 pathway. PMID:27084994

  11. Genetic variation in BCL2 3'-UTR was associated with lung cancer risk and prognosis in male Chinese population.

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    Ping Xu

    Full Text Available OBJECTIVES: Bcl-2 is a critical apoptosis inhibitor with established carcinogenic potential, and can confer cancer cell resistance to therapeutic treatments by activating anti-apoptotic cellular defense. We hypothesized that genetic variants of BCL2 gene may be associated with lung cancer susceptibility and prognosis. METHODS: Three selected tagSNPs of BCL2 (rs2279115, rs1801018, and rs1564483 were genotyped in 1017 paired male Chinese lung cancer cases and controls by TaqMan assay. The associations of these variants with risk of lung cancer and overall survival of 242 male advanced non-small-cell lung cancer (NSCLC patients were separately investigated. RESULTS: Compared with the BCL2 3'UTR rs1564483GG genotype, the rs1564483GA, AA, and GA+AA genotypes were associated with significantly decreased susceptibilities of lung cancer in male Chinese (adjusted OR = 0.78, 0.73, and 0.76, P = 0.016, 0.038, and 0.007, respectively, while rs1564483A allele has a inverse dose-response relationship with lung cancer risk (P trend = 0.010. These effects were more evident in the elders, smokers, and subjects without family history of cancer (P trend = 0.017, 0.043 and 0.005, respectively. Furthermore, advanced NSCLC males carrying BCL2 rs1564483 GA+AA genotypes had significantly longer median survival time (Long-rank P = 0.036 and decreased death risk (adjusted HR = 0.69, P = 0.027 than patients with rs1564483GG genotype. These effects were more obvious in patients with smoking, stage IIIA, and in patients without surgery but underwent chemotherapy or radiotherapy (adjusted HR = 0.68, 0.49, 0.67, 0.69, 0.50, respectively, all P<0.05. CONCLUSION: The BCL2 3'UTR rs1564483A allele was associated with a decreased lung cancer risk and better survival for advanced NSCLC in male Chinese, which may offer a novel biomarker for identifying high-risk population and predicting clinical outcomes.

  12. 头针电刺激对急性脑梗死大鼠 Bax与 Bcl-2蛋白的影响%Effect of Scalp Acupuncture and Electrical Stimulation on Protein Bax and Bcl-2 in Rats with Acute Cerebral Infarction

    Institute of Scientific and Technical Information of China (English)

    李晓宁; 綦雪巍; 王振宇

    2016-01-01

    Objective:To observe the changes of protein Bax and Bcl -2 after treating acute cerebral infarction of rats with scalp acupuncture and electrical stimulation , and to discuss the mechanism on how these treatments affect cerebral infarction .Methods:Divide healthy female wistar rats into a treatment group , a model control group and a sham operation group randomly .Then divide every group into seven -days group and fourteen -days group by their treatment starting time after infarction ,with fifteen rats every time point .Make focal cerebral infarction models by suture method , then from the first day after making models , intervene the treatment group with scalp acupuncture , choose BaiHui and DaZhui acupoints , stimulate the acupoints with 100 Hz electrical wave , once per day , 30 minutes every time .For other two groups of rats , just fix them on the table with no in-tervention .After seven days and fourteen days , when the treatment was over , cut off their heads and take out the brains .Examine the infarction brain tissues with Western blot technology and determine the expressions of protein Bax and Bcl -2.Results:The expression of protein Bax was descended gradually , but the expression of Bcl-2 was ascended in the treatment group;in the model control group , the expressions of two proteins were descended .Compared with the model control group , the expressions of protein Bax in the treatment group on the seventh day and fourteenth day were descended ,and the expression of Bcl -2 was ascended .The difference had a statistical significance (P<0.05).Conclusion:Scalp acupuncture with electrical stimulation can effec-tively protect the infarction brain tissues .It can descend the expression of protein Bax , ascend the expression of Bcl-2 at the same time , maximize the difference between the expression of the two proteins , inhibit apoptosis in the ischemic regions .This might be the mechanism on how scalp acupuncture with electrical stimulation im-prove the

  13. Upregulation of Bax and Bcl-2 following prenatal cocaine exposure induces apoptosis in fetal rat brain

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    DaLiao Xiao, Lubo Zhang

    2008-01-01

    Full Text Available Cocaine abuse during pregnancy has been associated with numerous adverse perinatal outcomes. Aims: The present study was to determine whether prenatal cocaine exposure induced apoptosis and the possible role of Bcl-2 family genes in the programming cell death in fetal rat brain. Main methods: Pregnant rats were treated with cocaine subcutaneously (30 & 60 mg/kg/day from day 15 to 21 of gestation. Then the fetal and maternal brains were isolated. Key findings: Cocaine produced a dose-dependent decrease in fetal brain weight and brain/body weight ratio (P<0.05. Apoptotic nuclei in fetal brain were increased from 2.6 ± 0.1 (control to 8.1± 0.6 (low dose and 10.4 ± 0.2% (high dose (P<0.05. In accordance, cocaine dose dependently increased activities of caspase-3, caspase-8, and caspase-9 (% of control in the fetal brain by 177%, 155%, 174%, respectively, at 30 mg/kg/day, and by 191%, 176%, 274%, respectively, at 60 mg/kg/day. In contrast, cocaine showed no effect on caspase activities in the maternal brain. Cocaine produced a dose-dependent increase in both Bcl-2 and Bax protein expression in the fetal brain, and increased the ratio of Bax/Bcl-2 at dose of 30 mg/kg/day (P<0.05. Significance: Our study has demonstrated that prenatal cocaine exposure induces apoptosis in the fetal brain, and suggested that up-regulating Bax/Bcl-2 gene expression may be involved in cocaine-induced apoptosis. The increased apoptosis of neuronal cells in the fetal brain is likely to play a key role in cocaine-induced neuronal defects during fetal development.

  14. Effect of Exercise Training on Bcl-2 and Bax Gene Expression in the Rat Heart

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    Jafari

    2015-10-01

    Full Text Available Background Apoptosis or programmed cell death plays an important role in the development of cardiovascular diseases, particularly heart failure. Current evidence suggests that exercise training may alter apoptosis-related signaling in sensitive somatic tissues such as the myocardium. Objectives The aim of this study was to assess the effect of exercise training on Bcl-2 and Bax genes expression as key molecules involved in intrinsic pathway of apoptosis in the rat heart. Materials and Methods This study was conducted with a two-group experimental design (animal model and sixteen three-month-old male rats were selected and randomly divided to two groups of exercise training (n = 8 and control (n = 8. Rats in the trained group participated in an exercise training program for 12 weeks (10 – 60 m min-1, 24 – 33 min d-1, 15%. The rat hearts were removed forty-eight hours after the last training session. RNA extraction and synthesis of cDNA was done, and Bax and Bcl2 genes expression was analyzed through the Real Time-Polymerase Chain Reaction (RT-PCR. Kolmogorov-Smirnov and independent t-test were applied for statistical analysis of the data (P 0.05. However, Bcl2 expression was higher in the trained group compared to the control group (11%. Conclusions In general, it seems that three-month exercise training was effective in reducing cardiac mitochondrial pro-apoptotic protein. However, considering the results of the Bcl2 gene expression, more researches are needed to identify effects of exercise trainings on indices of myocardial apoptosis.

  15. Bcl-2基因与神经生长因子(NGF)抑制神经细胞凋亡的研究%Abaissement role of bcl-2 gene and NGF on the apoptosis of nerve cel s

    Institute of Scientific and Technical Information of China (English)

    韩贵和; 魏威; 顾军

    2013-01-01

    12 cells with slow virus plasmid carrying the bcl-2 gene, which were damaged by H2O2.Group C: PC12 cells with slow virus plasmid carryingthe bcl-2 gene, which were damaged by H2O2, were treated with NGF.Group D: PC12 cells with slow virus plasmid. Group E: PC12 cells with slow virus plasmid, which were damaged by H2O2. Group F: PC12 cells with slow virus plasmid, which were damaged by H2O2., were treated with NGF.The rate of apoptosis was detected by flow cytometry .By BCA(bicinchoninic acid) method,the proteinum concentration of bcl-2 gene expression was detected.Results The apoptosis rate of group A was lower than that of groupD.The apoptosis rate of group B was lower than that of groupE.The apoptosis rate of group C was lower than that of groupB and was lower than that of groupF.Protein concentrations of bcl-2 gene expression of group A was higher than that of group D.Protein concentrations of bcl-2 gene expression of group B was higher than that of group E Protein concentrations of bcl-2 gene expression of group C was higher than that of group B and was higher than that of group F.There were statistical y significant difference between two groups (p<0.05).Conclusion Both bcl-2 gene and NGF can inhibit apoptosis of normal nerve cells and can enhance resistance ability of nerve cellto be damaged. There were synergia abaissement role on the apoptosis of nerve cells when they were used together.

  16. 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.

  17. 奥曲肽对人肝星状细胞凋亡及Bcl-2/Bax表达的影响%Effects of octreotide on the apoptosis of human HSCs and expression of Bcl-2/Bax in HSCs

    Institute of Scientific and Technical Information of China (English)

    李春艳; 贾丽萍; 石蕾; 周贤

    2015-01-01

    Objective To investigate the effects of octreotide on the apoptosis of human hepatic stellate cells (HSCs) and expression of Bcl-2/Bax in HSCs,and to reveal the mechanism underlying octreotide against hepatic fibrosis. Methods HSCs lines (HSC-LX2) were incubated with different concentrations of octreotide for 24 and 48 hours. Cell apoptosis was evaluated by Fitc-tunel fluorescence staining. Bcl-2 and Bax protein exoression in HSC-LX2 was detected by immunocytochemistry. Meanwhile, Bcl-2 protein of HSC-LX2 were detected by Western blot assay. Results Octreotide could promote the apoptosis of HSC-LX2, and the apoptosis rate was significantly increased with the concentration of octreotide(P < 0.05). The HSC-LX2 were incubated with the same concentration of octreotide for 24 and 48 hours, the cell apoptosis rate of 48-hour octreotide treatment was significantly higher than that of 24-hour octreotide treatment (P < 0.05). The immunocytochemistry result indicated that octreotide could significantly decrease Bcl-2 expression and increase Bax expression in HSC-LX2 (P<0.05); Western blot assay showed that octreotide could also significantly inhibit Bcl-2 expression in HSC-LX2 (P<0.05). Conclusions Octreotide could induce the apoptosis of HSCs in a dose-and time-dependent manner, the mechanism of octreotide inducing HSCs apoptosis might be associated with down-regulation of Bcl-2 and upregulation of Bax in HSC.%目的:观察奥曲肽对活化人肝星状细胞凋亡和凋亡相关蛋白Bcl-2/Bax 表达的影响,探讨奥曲肽抗肝纤维化可能的作用机制。方法:不同浓度的奥曲肽作用于传代的人肝星状细胞株(HSC-LX2)24 h、48 h后,应用FITC-TUNEL检测各组细胞凋亡,应用免疫细胞化学法检测HSC-LX2中Bcl-2、Bax蛋白表达,应用Western-blot法检测HSC-LX2中Bcl-2蛋白表达。结果:奥曲肽可促进HSC-LX2细胞调亡,细胞凋亡率随奥曲肽浓度增加而增高(P <0.05);与24 h比较,相

  18. Susceptibility of striatal neurons to excitotoxic injury correlates with basal levels of Bcl-2 and the induction of P53 and c-Myc immunoreactivity.

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    Liang, Zhong-Qin; Wang, Xiao-Xia; Wang, Yumei; Chuang, De-Maw; DiFiglia, Marian; Chase, Thomas N; Qin, Zheng-Hong

    2005-11-01

    The present studies evaluated the potential contribution of Bcl-2, p53, and c-Myc to the differential vulnerability of striatal neurons to the excitotoxin quinolinic acid (QA). In normal rat striatum, Bcl-2 immunoreactivity (Bcl-2-i) was most intense in large aspiny interneurons including choline acetyltransferase positive (CAT+) and parvalbumin positive (PARV+) neurons, but low in a majority of medium-sized neurons. In human brain, intense Bcl-2-i was seen in large striatal neurons but not in medium-sized spiny projection neurons. QA produced degeneration of numerous medium-sized neurons, but not those enriched in Bcl-2-i. Many Bcl-2-i-enriched interneurons including those with CAT+ and PARV+ survived QA injection, while medium-sized neurons labeled for calbindin D-28K (CAL D-28+) did not. In addition, proapoptotic proteins p53-i and c-Myc-i were robustly induced in medium-sized neurons, but not in most large neurons. The selective vulnerability of striatal medium spiny neurons to degeneration in a rodent model of Huntington's disease appears to correlate with their low levels of Bcl-2-i and high levels of induced p53-i and c-Myc-i. PMID:15922606

  19. Bcl-2 Targeted Structural Based Computer Aided Drug Design (CAAD For Therapeutic Assessment of Ricin in Prostate Cancer

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    Meghraj Singh Baghel

    2015-03-01

    Full Text Available Cancer is referred as uncontrolled growth of abnormal cell mass. Out of the several types of cancer, prostate cancer (PC has become a major public health problem in men worldwide. Bcl-2 and p27 proteins are important regulatory molecules of cell cycle. Failure of cell cycle regulation leads to uncontrolled cell proliferation and causes cancer. For designing an effective structural based targeted drug, the assessment of protein-protein and protein-ligand interaction is indispensable. Therefore for treatment of PC, we selected a ribosome inactivating protein, Ricin, for assessment of its therapeutic nature. In the present work through CLUSTAL-W phylogenetic analysis, we found that Bcl-2 protein was found more conserved than p27. Further Bcl-2 was selected as target molecule for docking study with Ricin protein and other chemically synthetic inhibitor molecules i.e. 2-difluoromethylornithine (DFMO and Sarcosine, as lead molecule. Through HEX5.1 docking software docking was performed between targeted receptor and lead molecules. Energy maximum (Emax= -93.12 and energy minimum (Emin= -163.07 was observed for docking complex of optimised and energy minimised structure of Bcl-2 receptor with Ricin, which in turn shows that it is highly stable interaction. On the other hand, for synthetic inhibitors, we found energy maximum (DFMO; Emax= -77.17, Emin= -117.83 and Sarcosine; Emax= -72.23, Emin= -103.00 and energy minimum, which are significant more as compared to Ricin docking complex. Due to ricin docking complex having less energies shows stable interaction with Bcl-2. We also observed that Ricin is less toxic (lesser log P value as compared to other molecules by toxicity analysis by ADME/TOX server. These evidences show this Ricin could be better drug for PC. Further results are needed to validate by in vitro and in vivo study to make proper elucidation of drug for better PC treatment.

  20. Thymosin beta 4 protects cardiomyocytes from oxidative stress by targeting anti-oxidative enzymes and anti-apoptotic genes.

    Directory of Open Access Journals (Sweden)

    Chuanyu Wei

    Full Text Available BACKGROUND: Thymosin beta-4 (Tβ4 is a ubiquitous protein with many properties relating to cell proliferation and differentiation that promotes wound healing and modulates inflammatory mediators. The mechanism by which Tβ4 modulates cardiac protection under oxidative stress is not known. The purpose of this study is to dissect the cardioprotective mechanism of Tβ4 on H(2O(2 induced cardiac damage. METHODS: Rat neonatal cardiomyocytes with or without Tβ4 pretreatment were exposed to H(2O(2 and expression of antioxidant, apoptotic, and anti-inflammatory genes was evaluated by quantitative real-time PCR and western blotting. ROS levels were estimated by DCF-DA using fluorescent microscopy and fluorimetry. Selected antioxidant, anti-inflammatory and antiapoptotic genes were silenced by siRNA transfections in neonatal cardiomyocytes and effect of Tβ4 on H(2O(2-induced cardiac damage was evaluated. RESULTS: Pre-treatment of Tβ4 resulted in reduction of the intracellular ROS levels induced by H(2O(2 in cardiomyocytes. Tβ4 pretreatment also resulted in an increase in the expression of antiapoptotic proteins and reduction of Bax/BCl(2 ratio in the cardiomyocytes. Pretreatment with Tβ4 resulted in stimulating the expression of antioxidant enzymes copper/zinc SOD and catalase in cardiomyocytes at both transcription and translation levels. Tβ4 treatment resulted in the increased expression of anti-apoptotic and anti-inflammatory genes. Silencing of Cu/Zn SOD and catalase gene resulted in apoptotic cell death in the cardiomyocytes which was prevented by treatment with Tβ4. CONCLUSION: This is the first report that demonstrates the effect of Tβ4 on cardiomyocytes and its capability to selectively upregulate anti-oxidative enzymes, anti-inflammatory genes, and antiapoptotic enzymes in the neonatal cardiomyocytes thus preventing cell death thereby protecting the myocardium. Tβ4 treatment resulted in decreased oxidative stress and inflammation in the

  1. Apoptosis and the activity of ceramide, Bax and Bcl-2 in the lungs of neonatal rats exposed to limited and prolonged hyperoxia

    Directory of Open Access Journals (Sweden)

    Bitar Fadi F

    2006-07-01

    Full Text Available Abstract Background The aim of the study is to examine the effect of limited and prolonged hyperoxia on neonatal rat lung. This is done by examining the morphologic changes of apoptosis, the expression of ceramide, an important mediator of apoptosis, the expression of inflammatory mediators represented by IL-1β and the expression of 2 proto-oncogenes that appear to modulate apoptosis (Bax and Bcl-2. Methods Newborn rats were placed in chambers containing room air or oxygen above 90% for 7 days. The rats were sacrificed at 3, 7 or 14 days and their lungs removed. Sections were fixed, subjected to TUNEL, Hoechst, and E-Cadherin Staining. Sections were also incubated with anti-Bcl-2 and anti-Bax antisera. Bcl-2 and Bax were quantitated by immunohistochemistry. Lipids were extracted, and ceramide measured through a modified diacylglycerol kinase assay. RT-PCR was utilized to assess IL-1β expression. Results TUNEL staining showed significant apoptosis in the hyperoxia-exposed lungs at 3 days only. Co-staining of the apoptotic cells with Hoechst, and E-Cadherin indicated that apoptotic cells were mainly epithelial cells. The expression of Bax and ceramide was significantly higher in the hyperoxia-exposed lungs at 3 and 14 days of age, but not at 7 days. Bcl-2 was significantly elevated in the hyperoxia-exposed lungs at 3 and 14 days. IL-1β expression was significantly increased at 14 days. Conclusion Exposure of neonatal rat lung to hyperoxia results in early apoptosis documented by TUNEL assay. The early rise in Bax and ceramide appears to overcome the anti-apoptotic activity of Bcl-2. Further exposure did not result in late apoptotic changes. This suggests that apoptotic response to hyperoxia is time sensitive. Prolonged hyperoxia results in acute lung injury and the shifting balance of ceramide, Bax and Bcl-2 may be related to the evolution of the inflammatory process.

  2. Antiapoptotic Effects of EGb 761

    Directory of Open Access Journals (Sweden)

    Norma Serrano-García

    2013-01-01

    Full Text Available Ginkgo biloba extracts have long been used in Chinese traditional medicine for hundreds of years. The most significant extract obtained from Ginkgo biloba leaves has been EGb 761, a widely used phytopharmaceutical product in Europe. EGb 761 is a well-defined mixture of active compounds, which contains two main active substances: flavonoid glycosides (24–26% and terpene lactones (6–8%. These compounds have shown antiapoptotic effects through the protection of mitochondrial membrane integrity, inhibition of mitochondrial cytochrome c release, enhancement of antiapoptotic protein transcription, and reduction of caspase transcription and DNA fragmentation. Other effects include the reduction of oxidative stress (which has been related to the occurrence of vascular, degenerative, and proliferative diseases, coupled to strong induction of phase II-detoxifying and cellular defense enzymes by Nrf2/ARE activation, in addition to the modulation of transcription factors, such as CREB, HIF-1α, NF-κB, AP-1, and p53, involved in the apoptosis process. This work reviews experimental results about the antiapoptotic effects induced by the standardized extract of Ginkgo biloba leaves (EGb 761.

  3. Bcl-2 Regulates Reactive Oxygen Species Signaling and a Redox-Sensitive Mitochondrial Proton Leak in Mouse Pancreatic β-Cells.

    Science.gov (United States)

    Aharoni-Simon, Michal; Shumiatcher, Rose; Yeung, Anthony; Shih, Alexis Z L; Dolinsky, Vernon W; Doucette, Christine A; Luciani, Dan S

    2016-06-01

    In pancreatic β-cells, controlling the levels of reactive oxygen species (ROS) is critical to counter oxidative stress, dysfunction and death under nutrient excess. Moreover, the fine-tuning of ROS and redox balance is important in the regulation of normal β-cell physiology. We recently demonstrated that Bcl-2 and Bcl-xL, in addition to promoting survival, suppress β-cell glucose metabolism and insulin secretion. Here, we tested the hypothesis that the nonapoptotic roles of endogenous Bcl-2 extend to the regulation of β-cell ROS and redox balance. We exposed mouse islet cells and MIN6 cells to the Bcl-2/Bcl-xL antagonist Compound 6 and the Bcl-2-specific antagonist ABT-199 and evaluated ROS levels, Ca(2+) responses, respiratory control, superoxide dismutase activity and cell death. Both acute glucose stimulation and the inhibition of endogenous Bcl-2 progressively increased peroxides and stimulated superoxide dismutase activity in mouse islets. Importantly, conditional β-cell knockout of Bcl-2 amplified glucose-induced formation of peroxides. Bcl-2 antagonism also induced a mitochondrial proton leak that was prevented by the antioxidant N-acetyl-L-cysteine and, therefore, secondary to redox changes. We further established that the proton leak was independent of uncoupling protein 2 but partly mediated by the mitochondrial permeability transition pore. Acutely, inhibitor-induced peroxides promoted Ca(2+) influx, whereas under prolonged Bcl inhibition, the elevated ROS was required for induction of β-cell apoptosis. In conclusion, our data reveal that endogenous Bcl-2 modulates moment-to-moment ROS signaling and suppresses a redox-regulated mitochondrial proton leak in β-cells. These noncanonical roles of Bcl-2 may be important for β-cell function and survival under conditions of high metabolic demand. PMID:27070098

  4. 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.

  5. The T cell receptor repertoire of CD4-8+ thymocytes is altered by overexpression of the BCL-2 protooncogene in the thymus

    OpenAIRE

    1994-01-01

    The bcl-2 gene encodes an intracellular, membrane-associated protein that protects immature cortical thymocytes from a wide variety of apoptotic stimuli, including glucocorticoids, radiation, and anti-CD3 treatment. Since cortical thymocytes are the primary target cells for thymic positive and negative selection processes, and since these processes are associated with cell death, we evaluated the role of bcl- 2 in T cell development in two ways. In the first approach, transgenic mice expressi...

  6. Analysis of the Expression of Fas, FasL and Bcl-2 in the Pathogenesis of Autoimmune Thyroid Disorders

    Institute of Scientific and Technical Information of China (English)

    Shenren Chen; S.M.Fazle Akbar; Zhichao Zhen; Yiping Luo; Lijuan Deng; Haihua Huang; Linxin Chen; Wei Li

    2004-01-01

    To investigate the expression of apoptosis-related protein (Fas, FasL, and Bcl-2) in the pathogenesis of autoimmune thyroid disorders (ATDs), immunohistochemical staining was performed on 20 Hashimoto's thyroiditis (HT), 20 Graves' disease (GD), and 20 thyroid follicular adenoma (TFA, as control). All the cases expressed Fas, mainly on the cell surface and cytoplasm. FasL was found in 17 cases of the TFA. Bcl-2 was detected in 15 cases of HT, 19 of GD and 17 of TFA. In TFA, a moderate Fas expression and a minimal or no FasL expression was detected on follicular cells. In HT, the follicles adjacent to infiltrating lymphocytes showed increased levels of Fas and FasL expression. A weaker staining of Fas and FasL was exhibited on infiltrating lymphocytes than on thyrocytes. In a comparison of GD with HT, thyrocytes and lymphocytes showed similar Fas staining, but for FasL the staining was rather weaker in HT. The expression of Bcl-2 was nearly identical in GD and TFA, but much weaker on the follicular cells in vicinity of lymphocytes and on the lymphocytes located in germinal centers of HT tissues. The expression of Fas, FasL, Bcl-2 in Hashimoto's thyroiditis and Graves' disease were almost same. FasL strong expression and Bcl-2 weak expression on the follicles in HT may induce apoptosis. These results provided evidence for expression of Fas, FasL and Bcl-2 in the pathogenesis of autoimmune thyroid disease. The lymphocytes seem not to be directly engaged in the process via their own FasL, but they may provide some cytokines that, in turn, upregulate Fas and/or FasL expression to induce apoptosis.

  7. Social stress exacerbates stroke outcome by suppressing Bcl-2 expression

    OpenAIRE

    DeVries, A. Courtney; Joh, Hung-Dong; Bernard, Ora; Hattori, Kimihiko; Hurn, Patricia D.; Traystman, Richard J; Alkayed, Nabil J.

    2001-01-01

    The relationship between stressful life events and the onset of disease is well documented. However, the role of psychological stress as a risk factor for life-threatening cerebrovascular insults such as stroke remains unspecified, but could explain individual variation in stroke outcome. To discover the mechanisms through which psychological stress may alter stroke outcome, we modeled the effects of chronic social intimidation and stress on ischemia-induced bcl-2 ...

  8. 王氏连朴饮对脾胃湿热证模型大鼠胃黏膜 P53、BcI-2和 COX-2蛋白表达的影响%Effect of Wang's Lian Pu Decoction on Protein Expression of P53, Bcl -2 and COX -2 in Gastric Mucosa of Rat Model with Splenogastric Damp-heat Syndrome

    Institute of Scientific and Technical Information of China (English)

    黄琴; 王晶; 王和生; 王俊霞; 冯康; 谭芸

    2014-01-01

    Objective To observe the effect of Wang's Lian Pu Decoction(WLPD)on protein expression of proliferation and apoptosis correlated P53, Bcl-2, COX-2 genes in gastric mucosa of rat model wiht splenogastric damp-heat syndrome(SDHS),and to explore its possible therapeutic mechanism for SDHS. Methods Fifty Sprague Dawley rats were evenly divided into normal control group, model group, and high-, middle- and low-dosage WLPD groups (1.94,0.97,0.48 g·mL-1). SDHS rat model was established by the combined method of damp-heat environment and feeding with high fat and sugar diet and wine. The intervention with gastric gavage of WLPD was given simultaneously together with the modeling. The treatment lasted 7 days,and the effects of WLPD on protein expression levels of P53, Bcl-2 and COX-2 genes were observed. Results The protein expression of p53, Bcl-2 and COX-2 genes was localized in cytoplasm and their expression levels were significantly increased in the model group as compared to normal control group(P < 0.01). High-,middle- and low-dosage WLPD showed an effect on down-regulating the protein expression of P53,Bcl-2 and COX-2 genes to certain extent,and the middle-dose had the strongest effect, the difference being significant compared with the model group(P < 0.01). Conclusion WLPD may down-regulate the protein expression of P53,Bcl-2 and COX-2 genes in gastric mucosa of SDHS rats,correct the imbalance of the proliferation and apoptosis of gastric mucosa cells,thus has protective effect on the gastric mucosa.%目的:观察王氏连朴饮对脾胃湿热证模型大鼠胃黏膜增殖与凋亡相关 P53、Bcl-2和 COX-2蛋白表达的影响,探讨该方治疗脾胃湿热证获效的可能作用机制。方法取 SD 大鼠50只,随机分为正常对照组,模型组,王氏连朴饮高、中、低剂量组(1.94,0.97,0.48 g·mL-1),共5组,每组10只。除正常组饲以普通饲料外,其余4组均以湿热环境加高脂高糖饮食和白酒综合法复

  9. Tissue factor/FVIIa activates Bcl-2 and prevents doxorubicin-induced apoptosis in neuroblastoma cells

    Directory of Open Access Journals (Sweden)

    Alvarado Carlos S

    2008-03-01

    Full Text Available Abstract Background Tissue factor (TF is a transmembrane protein that acts as a receptor for activated coagulation factor VII (FVIIa, initiating the coagulation cascade. Recent studies demonstrate that expression of tumor-derived TF also mediates intracellular signaling relevant to tumor growth and apoptosis. Our present study investigates the possible mechanism by which the interaction between TF and FVIIa regulates chemotherapy resistance in neuroblastoma cell lines. Methods Gene and siRNA transfection was used to enforce TF expression in a TF-negative neuroblastoma cell line and to silence endogenous TF expression in a TF-overexpressing neuroblastoma line, respectively. The expression of TF, Bcl-2, STAT5, and Akt as well as the phosphorylation of STAT5 and Akt in gene transfected cells or cells treated with JAK inhibitor and LY294002 were determined by Western blot assay. Tumor cell growth was determined by a clonogenic assay. Cytotoxic and apoptotic effect of doxorubicin on neuroblastoma cell lines was analyzed by WST assay and annexin-V staining (by flow cytometry respectively. Results Enforced expression of TF in a TF-negative neuroblastoma cell line in the presence of FVIIa induced upregulation of Bcl-2, leading to resistance to doxorubicin. Conversely, inhibition of endogenous TF expression in a TF-overexpressing neuroblastoma cell line using siRNA resulted in down-regulation of Bcl-2 and sensitization to doxorubicin-induced apoptosis. Additionally, neuroblastoma cells expressing high levels of either endogenous or transfected TF treated with FVIIa readily phosphorylated STAT5 and Akt. Using selective pharmacologic inhibitors, we demonstrated that JAK inhibitor I, but not the PI3K inhibitor LY294002, blocked the TF/FVIIa-induced upregulation of Bcl-2. Conclusion This study shows that in neuroblastoma cell lines overexpressed TF ligated with FVIIa produced upregulation of Bcl-2 expression through the JAK/STAT5 signaling pathway, resulting

  10. Rapamycin increases pCREB, Bcl-2, and VEGF-A through ERK under normoxia

    Institute of Scientific and Technical Information of China (English)

    Yudong Liu; Qixin Zheng; Hongbin Wu; Xiaodong Guo; Jingfeng Li; Shaofei Hao

    2013-01-01

    Rapamycin may serve as a new anti-osteosarcoma (OSA) agent due to its ability to inhibit the metastatic behavior of OSA.However,only limited benefit is observed in rodent studies and clinical trials using rapamycin as a single agent in the treatment of OSA.The target of rapamycin,mammalian target of rapamycin has multiple biological functions and may be linked with the kinases that mediate the phosphorylation of cyclic AMP-responsive element-binding (CREB) protein,an import factor in tumor progression.By employing an OSA cell line MG-63,we investigated how rapamycin regulates the phosphorylation of CREB (pCREB) at Ser133 and the expressions of two putative CREB targets,B-cell lymphoma 2 (Bcl-2)and vascular endothelial growth factor-A (VEGF-A).Under normoxia,we found that rapamycin (100nM)induced an increase of pCREB that was prevented by mitogen-activated protein kinase (MEK)/extracellular signal-regulated kinase (ERK) inhibitor U0126 or cAMP-dependent protein kinase (PKA) inhibitor H89.However,H89 enhanced Akt phosphorylation and did not decrease the cell viability upon rapamycin treatment.In contrast,U0126 did not enhance Akt phosphorylation and decreased the cell viability upon rapamycin treatment.Moreover,U0126 prevented the rapamycin-induced increase of Bcl-2 and VEGF-A levels.Under hypoxia,rapamycin effectively prevented the hypoxia-induced increase of pCREB,Bcl-2,and VEGF-A.Our study demonstrated that rapamycin might be less effective in treating OSA cells under normoxia and provided the rationale for a combination of rapamycin and MEK/ERK inhibitor in the treatment of OSA.

  11. Bcl-2、NF-KB在腮腺腺样囊性癌中的表达及临床意义%Expression and clinical significance of Bcl-2、NF-KB in adenoid cystic carcinoma of the parotid gland

    Institute of Scientific and Technical Information of China (English)

    张新华; 南欣荣

    2013-01-01

    目的:探讨Bcl-2和NF-KB在腮腺腺样囊性癌中的表达及意义.方法:应用免疫组化SP法检侧49例腮腺腺样囊性癌和20例正常腮腺组织中Bcl-2和NF-KB的表达情况,统计学分析采用x2检验,P<0.05判断为具有显著性差异.结果:Bcl-2和NF-KB的表达强度显著高于正常腮腺组织(P<0.05),Bcl-2、NF-KB的表达与病理无关(P>0.05),与TNM分期有关,Bcl-2和NF-KB两者存在正相关性(P<0.05,Kappa=0.387).结论:在腮腺腺样囊性癌的发生、发展过程中NF-KB通过上调Bcl-2的表达发挥作用.%Objective To explore the expression and Clinical Significance of Bcl-2,NF-KB in in Adenoid Cystic Carcinoma of the Parotid Gland.Methods Detected the expression of Bcl-2,NF-KB gene protein in 49 cases of adenoid cystic carcinoma of parotid gland was block embedded tissue in Immunohistochemistry SP method,20 cases of normal parotid tissue as control.Using x2 test,the statistically significant difference is defined as P<0.05.Results The total expression rate of Bcl-2 and NF-KB in adenoid cystic carcinoma group are significantly higher than the normal parotid group (P<0.05),the expression of different pathological typing of Bcl-2 and NF-KB are no differences (P > 0.05),the expression of clinical TNM stage of Bcl-2 and NF-KB are differences (P<0.05).There is positive correlation between Bcl-2 and NF-KB (P<0.05 kappa=0.387).Conclusion NF-KB plays a important role by up-regulating the expression of Bcl-2 in the occurrence and development process of adenoid cystic carcinoma of parotid gland.

  12. 甘草黄酮对大强度耐力运动大鼠肾脏组织Ca2+、Mg2+-ATPase及Bax,Bc1-2蛋白表达的影响%Effect of High-Intensity Endurance Exercise on Ca2+,Mg2+-ATPase and Bax, Bcl-2 Protein Expression With Glycyrrhiza Flavonoids in rat Nephridial Tissue

    Institute of Scientific and Technical Information of China (English)

    王东旭; 陈艳艳

    2013-01-01

    Objective To explore Glycyrrhiza Elavonoids on the rat nephridial tissue of Ca2+, Mg2+-ATPase and Bax, Bcl-2 protein expression with high-intensity endurance exercise. Methods The twenty-four healthy male rats were randomly divided into quiet groups, high-intensity exercise group and exercise plus Glycyrrhiza Elavonoids group, After 6 weeks of treadmill training, Using the box of reagent and immunity histochemistry examined the changing of Ca2+, Mg2+-ATPase and Bax, Bcl-2 protein expression on each groups . Results Compared with the quiet groups, the activity of Ca2+, Mg2+-ATPase both had significant droped (P<0.01), and the groups of plus drog had very difference increased than high-intendity exerxise groups (P<0.01); High-intensity endurance exercise group and exercise dosing rats AI apoptosis index increased in varying degrees;high-intensity exercise group (MOD) were very significant difference(P<0.01), exercise plus drug group Bac protein expression (MOD)were very significant difference (P<0.01); Exercise plus drug group Bcl-2 protein expression(MOD) with the high-intersity exercise group had significant difference(P<0.01), High-intensity exercise group and exercise plus drug group Bax/Bcl-2 ratio of distribution is significantly difference degrees of difference(P<0.05,P<0.01).%目的:探讨甘草黄酮对大强度耐力运动大鼠肾脏组织Ca2+、Mg2+-ATPase及Bax、Bcl-2表达的影响。方法:选取SD雄性健康大鼠24只,随机分为安静组、大强度运动组和运动加药组;采用跑台训练6周后取材,应用试剂盒和免疫组织化学法测检测各组大鼠肾脏组织Ca2+、Mg2+-TPase活性及Bax和Bcl-2表达的变化。结果:与安静对照组相比,大强度运动组和运动加药组肾脏组织Ca2+、Mg2+-TPase活性均呈非常显著性下降(P<0.01);其中运动加药组Ca2+、Mg2+-TPase活性均较大强度运动组具有非常显著差异性提高(P<0.01);大强度耐力运动组和运动加

  13. Nitric oxide as a pro-apoptotic as well as anti-apoptotic modulator.

    Science.gov (United States)

    Choi, Byung-Min; Pae, Hyun-Ock; Jang, Seon Il; Kim, Young-Myeong; Chung, Hun-Taeg

    2002-01-31

    Nitric oxide (NO), synthesized from L-arginine by NO synthases, is a small, lipophilic, diffusible, highly reactive molecule with dichotomous regulatory roles in many biological events under physiological and pathological conditions. NO can promote apoptosis (pro-apoptosis) in some cells, whereas it inhibits apoptosis (anti-apoptosis) in other cells. This complexity is a consequence of the rate of NO production and the interaction with biological molecules such as metal ion, thiol, protein tyrosine, and reactive oxygen species. Long-lasting overproduction of NO acts as a pro-apoptotic modulator, activating caspase family proteases through the release of mitochondrial cytochrome c into cytosol, up-regulation of the p53 expression, and alterations in the expression of apoptosis-associated proteins, including the Bcl-2 family. However, low or physiological concentrations of NO prevent cells from apoptosis that is induced by the trophic factor withdrawal, Fas, TNFalpha/ActD, and LPS. The anti-apoptotic mechanism is understood on the basis of gene transcription of protective proteins. These include: heat shock protein, hemeoxygenase, or cyclooxygenase-2 and direct inhibition of the apoptotic executive effectors caspase family protease by S-nitrosylation of the cysteine thiol group in their catalytic site in a cell specific way. Our current understanding of the mechanisms by which NO exerts both pro- and anti-apototic action is discussed in this review article. PMID:16248976

  14. Prognostic evaluation of CD44 expression in correlation with bcl-2 and p53 in colorectal cancer

    Directory of Open Access Journals (Sweden)

    G. Peros

    2011-08-01

    Full Text Available To investigate the expression of CD44 in colorectal cancer and examine its association with clinicopathological features, bcl-2, p53 and long-term outcome, paraffin-embedded tumour specimens from 61 patients with Dukes stage B (AJCC/UICC stage I and 39 patients with Dukes stage C (AJCC/UICC stage III colorectal adenocarcinoma were assessed by immunohistochemistry. The expression of CD44, bcl-2 and p53 were correlated with 5-year follow-up. Low CD44 expression was present in 30%, moderate in 30% and extensive in 40% of cases. It was not related to patient sex and age but was related to tumour differentiation, stage and tumour site. No association was demonstrated between CD44 and bcl-2. However, there was significant evidence of an association between CD44 and p53 in 66 cases in which p53 was previously assessed. There was a trend towards increased survival in patients whose tumours expressed lower levels of CD44 protein. When entered into multivariate analysis model, which also included bcl-2 and p53, CD44 staining emerged as an indicator of poor prognosis in colorectal cancer patients.

  15. Emodin inhibits LOVO colorectal cancer cell proliferation via the regulation of the Bcl-2/Bax ratio and cytochrome c.

    Science.gov (United States)

    Ma, Liang; Li, Wusheng

    2014-10-01

    In this study, the effect of emodin and its mechanism of action were investigated in LOVO colorectal cancer cells. Cell growth was determined using a Cell Counting kit-8 assay, and the results demonstrated that emodin significantly inhibited the growth of LOVO cells in a concentration-dependent manner. In order to investigate the anticancer mechanism of emodin, reverse transcription polymerase chain reaction assays were performed to determine the B-cell lymphoma-2 (Bcl-2)/Bcl-2-associated X protein (Bax) expression ratio in LOVO colorectal cancer cells following treatment with emodin. The results showed that emodin induced a significant increase in the Bax expression level and a marked reduction of the Bcl-2 expression level in LOVO cells. In addition, emodin was found to have an inhibitory effect on the mitochondrial membrane potential and the results from the western blot analysis revealed that cytochrome c was released from the mitochondria to the cytoplasm. In combination, these results suggest that emodin inhibits cancer cell growth via the regulation of the Bcl-2/Bax ratio and by its effect on the mitochondrial apoptosis pathway.

  16. Leptin is an anti-apoptotic effector in placental cells involving p53 downregulation.

    Directory of Open Access Journals (Sweden)

    Ayelén Rayen Toro

    Full Text Available Leptin, a peripheral signal synthetized by the adipocyte to regulate energy metabolism, can also be produced by placenta, where it may work as an autocrine hormone. We have previously demonstrated that leptin promotes proliferation and survival of trophoblastic cells. In the present work, we aimed to study the molecular mechanisms that mediate the survival effect of leptin in placenta. We used the human placenta choriocarcinoma BeWo and first trimester Swan-71 cell lines, as well as human placental explants. We tested the late phase of apoptosis, triggered by serum deprivation, by studying the activation of Caspase-3 and DNA fragmentation. Recombinant human leptin added to BeWo cell line and human placental explants, showed a decrease on Caspase-3 activation. These effects were dose dependent. Maximal effect was achieved at 250 ng leptin/ml. Moreover, inhibition of endogenous leptin expression with 2 µM of an antisense oligonucleotide, reversed Caspase-3 diminution. We also found that the cleavage of Poly [ADP-ribose] polymerase-1 (PARP-1 was diminished in the presence of leptin. We analyzed the presence of low DNA fragments, products from apoptotic DNA cleavage. Placental explants cultivated in the absence of serum in the culture media increased the apoptotic cleavage of DNA and this effect was prevented by the addition of 100 ng leptin/ml. Taken together these results reinforce the survival effect exerted by leptin on placental cells. To improve the understanding of leptin mechanism in regulating the process of apoptosis we determined the expression of different intermediaries in the apoptosis cascade. We found that under serum deprivation conditions, leptin increased the anti-apoptotic BCL-2 protein expression, while downregulated the pro-apoptotic BAX and BID proteins expression in Swan-71 cells and placental explants. In both models leptin augmented BCL-2/BAX ratio. Moreover we have demonstrated that p53, one of the key cell cycle

  17. 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)

    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

  18. Different Expressions of HIF-1α, Bcl-2 and Baxin DU145 Prostate Cancer Cells Transplanted in Nude Mouse between X-Ray and Neutron Irradiation

    International Nuclear Information System (INIS)

    To investigate the radiobiologic effects of neutron and X-ray irradiation on DU-145 prostate carcinoma cells by identifying the differences of HIF-1α expression and apoptosis. Nude mice were injected with the human prostate cancer cell line, DU-145, and then irradiated with 2 Gy and 10 Gy X-rays, or 0.6 Gy and 3.3 Gy neutrons, respectively. The mice were sacrificed at 24 hours and 120 hours after irradiation. The expression levels of HIF-1α, Bcl-2 and Bax were compared with immunohistochemical staining and western blotting. The apoptotic indexes were compared with the Terminal deoxynucleotidyl biotin-dUTP nick and labeling (TUNEL) assay. At day 1, HIF-1α and Bcl-2 expression decreased, while Bax expression and the number of TUNEL positive cells increased in neutron irradiated groups for the control and X-ray irradiated groups. The Bcl-2/Bax ratio was significantly lower in the neutron irradiated groups regardless of dose (p=0.001). The same pattern of the differences in the expressions of the HIF-1α, Bcl-2, Bax, Bcl-2/Bax ratio, and apoptotic indexes were indentified at day 5. HIF-1α expression was related with Bcl-2 (p=0.031), Bax (p=0.037) expressions and the apoptotic indexes (p=0.016) at day 5. Neutron irradiation showed a decrease in HIF-1α, Bcl-2 expression, and Bcl-2/Bax ratio, but increased Bax expression regardless of dose. This study suggests that the differences radiobiological responses between photon and neutron irradiation may be related to different HIF-1α expression and subsequent apoptotic protein expressions

  19. Evaluation of anti-apoptotic activity of different dietary antioxidants in renal cell carcinoma against hydrogen peroxide

    Institute of Scientific and Technical Information of China (English)

    Garg Neeraj K; Mangal Sharad; Sahu Tejram; Mehta Abhinav; Vyas Suresh P; Tyagi Rajeev K

    2011-01-01

    Objective: To evaluate the anti-apoptotic and radical scavenging activities of dietary phenolics, namely ascorbic acid, -tocopherol acetate, citric acid, salicylic acid, and estimate H2O2-induced apoptosis in renal cell carcinoma cells. Methods: The intracellular antioxidant potency of antioxidants was investigated. H2O2-induced apoptosis in RCC-26 was assayed with the following parameters: cell viability (% apoptosis), nucleosomal damage and DNA fragmentation, bcl-2 levels and flow cytometery analysis (ROS production evaluation). Results: The anticancer properties of antioxidants such as ascorbic acid, - tocopherol acetate, citric acid, salicylic acid with perdurable responses were investigated. It was observed that these antioxidants had protective effect (anti-apoptotic activity) against hydrogen peroxide (H2O2) in renal cell carcinoma (RCC-26) cell line. Conclusions: This study reveals and proves the anticancer properties. However, in cancer cell lines anti-apoptotic activity can indirectly reflect the cancer promoter activity through radicals scavenging, and significantly protect nucleus and bcl-2.

  20. Effect of Sargassum fusiforme Polysaccharide on the Ethology and Expressions of Bcl-2 and Bax in Brain Tissue for Alzheimer's Disease Rat model%羊栖菜多糖对老年痴呆模型大鼠Bcl-2和Bax基因表达的分析

    Institute of Scientific and Technical Information of China (English)

    汤从容; 曹高忠; 叶晓兰

    2012-01-01

    Objective:To study effect of Sargassum fusiforme Polysaccharide( SFPS) on ethology and expressions of Bcl - 2 and Bax in brain tissue of AD rats. Methods:The D - galactose AD rat model was applied,and blank group,model group, Piracetam control group and herbal group were designed. Index change of ethology , expressions of Bcl -2 and Bax in brain tissue were tested. Results: AD model may decrease cognitive ability,the ratio of Bcl -2/Bax in the hippocampus came down(P <0.05 ). Compared to the model group,Sargassum fusiforme Polysaccharide with 0. 8 ,1. 6g/kg can alleviate cognitive ability significantly,and the action had a does —dependent increase,the ratio of Bcl -2/Bax increased(P< 0.05). Conclusion; Sargassum fusiforme Polysaccharide can up - regulate expression of protein Bax and down -regulate expression of Bcl - 2 in brain tissu. It inhibits apoptosis through regulating the expressions of Bcl - 2 and Bax protein in hippocampal , which might be one of mechanisms of Sargassum fusiforme Polysaccharide to prevent and treat AD disease.%目的:探讨羊栖菜多糖提取物(SFPS)对阿尔茨海默病(AD)大鼠模型行为的干预作用及脑皮质Bcl-2和Bax基因表达的影响.方法:制作D-半乳糖阿尔茨海默病大鼠模型,设计正常对照组、模型组、吡拉西坦片、羊栖菜多糖提取物不同剂量组,观察大鼠行为学及脑皮质Bcl -2和Bax基因表达指标的改变.结果:与正常对照组相比,模型组学习记忆能力显著下降(P<0.05),其Bcl - 2/Bax值下降;与模型组相比,0.8g/kg、1.6g/kg羊栖菜多糖提取物治疗组均能较好的改善学习记忆能力,且具有一定剂量依赖性,其Bcl - 2/Bax值增加.结论:SFPS能调节海马组织Bcl -2和Bax的表达,显著提高Bcl - 2/Bax值,抑制海马神经元的凋亡,改善AD大鼠学习记忆能力.

  1. The expression of Bax, Bcl-2 and NF-κB in the early stage of liver regeneration%Bax、Bcl-2和NF-κB在肝再生早期中的表达

    Institute of Scientific and Technical Information of China (English)

    杜赵康; 杨开明

    2014-01-01

    目的 研究在大鼠大部肝切除(partial hepatectomy,PH)术后细胞凋亡调节基因(Bcl-2 associated X protein Bax)、Bcl-2(B-cell lymphoma-2)及NF-κB(nuclear factor-kappa B)三者的分布和表达,探讨三者在肝再生早期中的调节机制及其相互调控作用.方法 采用SD大鼠35只分7组,每组5只构建大鼠肝脏再生模型,并在显微镜下观察肝大部切除后早期(0.5、1、4、6、8、12、24 h)肝组织的形态学变化,采用免疫组织化学SABC法检测Bax、Bcl-2、NF-κB在正常肝组织中的表达,并研究在肝再生早期中的分布及表达变化.结果 Bax、Bcl-2、NF-κB在正常肝组织未见表达,但在PH后30 min,Bax、Bcl-2及NF-κB即在肝细胞和胆管上皮细胞和肝血窦内皮内开始出现表达,PH后6h表达达到高峰,之后其表达逐渐下降,而Bcl-2的表达一直保持在较高水平.NF-κB于PH后6h表达出现高峰后其表达逐渐下调,24h时NF-κB表达上调,出现另一表达高峰.结论 肝大部切除后再生早期,存在着凋亡和抑制凋亡的分子调控机制,NF-κB的表达可能与激活Bcl-2、抑制肝细胞的凋亡从而促进肝细胞再生有关.

  2. Research Progress of Galectin-3,Bcl-2 and Embryo Development Termination%Galectin-3和Bcl-2与胚胎停育研究进展

    Institute of Scientific and Technical Information of China (English)

    徐耀辉

    2012-01-01

    Galectin-3 is a member of galectin family,which interacts with intracellular glycoprotein,cell surface molecules and extracellular matrix proteins by its carbohydrate recognition domains, participates the progress of embryo implantation,embryogenesis and placenta formation,and establishes and maintains a close relationship with pregnancy. Inhibitors of apoptosis protein Bcl-2 and Galectin-3 have significant sequence similarity,and may have the same apoptosis pathway,which participates in the growth and differentiation of villous trophoblast cells in people's earlier pregnancy and the process of decidualization of endometrium,in addition,playing a critical role in the villous production,growth,placenta formation and in its tissue structure rebuilding and functional perfection.%Galectin-3 是半乳糖凝集素家族中的一员,能通过其糖识别域与细胞内糖蛋白、细胞表面分子和细胞外基质蛋白相互作用,参与胚胎着床、胚胎发生和胎盘形成等过程,与妊娠成功建立和维持密切相关.凋亡抑制蛋白Bcl-2与Galectin-3有明显的序列相似性,可能存在共同细胞凋亡通路,在人早孕过程中参与了绒毛滋养层细胞的增殖和分化、子宫内膜蜕膜化的过程,在绒毛的发生、发育、胎盘形成和组织结构改建及功能完善等方面发挥着重要作用.

  3. Telomerase activity, estrogen receptors (α, β), Bcl-2 expression in human breast cancer and treatment response

    International Nuclear Information System (INIS)

    The mechanism for maintaining telomere integrity is controlled by telomerase, a ribonucleoprotein enzyme that specifically restores telomere sequences, lost during replication by means of an intrinsic RNA component as a template for polymerization. Among the telomerase subunits, hTERT (human telomerase reverse transcriptase) is expressed concomitantly with the activation of telomerase. The role of estrogens and their receptors in the transcriptional regulation of hTERT has been demonstrated. The current study determines the possible association between telomerase activity, the expression of both molecular forms of estrogen receptor (ERα and ERβ) and the protein bcl-2, and their relative associations with clinical parameters. Tissue samples from 44 patients with breast cancer were used to assess telomerase activity using the TRAP method and the expression of ERα, ERβ and bcl-2 by means of immunocytochemical techniques. Telomerase activity was detected in 59% of the 44 breast tumors examined. Telomerase activity ranged from 0 to 49.93 units of total product generated (TPG). A correlation was found between telomerase activity and differentiation grade (p = 0.03). The only significant independent marker of response to treatment was clinical stage. We found differences between the frequency of expression of ERα (88%) and ERβ (36%) (p = 0.007); bcl-2 was expressed in 79.5% of invasive breast carcinomas. We also found a significant correlation between low levels of telomerase activity and a lack of ERβ expression (p = 0.03). Lower telomerase activity was found among tumors that did not express estrogen receptor beta. This is the first published study demonstrating that the absence of expression of ERβ is associated with low levels of telomerase activity

  4. Intrinsic order and disorder in the bcl-2 member harakiri: insights into its proapoptotic activity.

    Directory of Open Access Journals (Sweden)

    Susana Barrera-Vilarmau

    Full Text Available Harakiri is a BH3-only member of the Bcl-2 family that localizes in membranes and induces cell death by binding to prosurvival Bcl-x(L and Bcl-2. The cytosolic domain of Harakiri is largely disorder with residual α-helical conformation according to previous structural studies. As these helical structures could play an important role in Harakiri's function, we have used NMR and circular dichroism to fully characterize them at the residue-atomic level. In addition, we report structural studies on a peptide fragment spanning Harakiri's C-terminal hydrophobic sequence, which potentially operates as a transmembrane domain. We initially checked by enzyme immunoassays and NMR that peptides encompassing different lengths of the cytosolic domain are functional as they bind Bcl-x(L and Bcl-2. The structural data in water indicate that the α-helical conformation is restricted to a 25-residue segment comprising the BH3 domain. However, structure calculation was precluded because of insufficient NMR restraints. To bypass this problem we used alcohol-water mixture to increase structure population and confirmed by NMR that the conformation in both milieus is equivalent. The resulting three-dimensional structure closely resembles that of peptides encompassing the BH3 domain of BH3-only members in complex with their prosurvival partners, suggesting that preformed structural elements in the disordered protein are central to binding. In contrast, the transmembrane domain forms in micelles a monomeric α-helix with a population close to 100%. Its three-dimensional structure here reported reveals features that explain its function as membrane anchor. Altogether these results are used to propose a tentative structural model of how Harakiri works.

  5. The enhancement of sensitivity of HL-60 cells to arsenic trioxide by Bcl-2 siRNA%以Bcl-2为靶标siRNA提高HL-60细胞对三氧化二砷敏感性的探讨

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Objective: To study whether the small-interference RNA (siRNA) targeting against Bcl-2 gene can enhance sensitivity of HL-60 cell to arsenic trioxide. Methods: SiRNA was transferred into the HL-60 cells. At 6 h after transfection, the cells were cultured with arsenic trioxide. The cell growth of the HL-60 cells was detected using MTT at 24, 48 and 72 h, respectively.The levels of the Bcl-2 protein and reactive oxygen species (ROS), as well as of the membrane potential of the mitochondrion were determined by flow cytometry. Results: The Bcl-2 siRNA significantly increased the inhibitory action of arsenic trioxide on growth of HL-60 cells. The combination of siRNA with arsenic trioxide resulted in decrease of the Bcl-2 protein level and increase of the ROS level, as well as significant descending of the membrane potential of mitochondrion of HL-60 (P < 0.05).Conclusion: The siRNAtargeting Bcl-2 can increase the sensitivity of the HL-60 leukemia cells to arsenic trioxide by inhibiting the expression of Bcl-2 protein.

  6. Two Novel 30K Proteins Overexpressed in Baculovirus System and Their Antiapoptotic Effect in Insect and Mammalian Cells

    Directory of Open Access Journals (Sweden)

    Wei Yu

    2013-01-01

    Full Text Available The 30K family of proteins is important in energy metabolism and may play a role in inhibiting cellular apoptosis in silkworms (Bombyx mori. Several 30K-family proteins have been identified. In this study, two new silkworm genes, referred to as Slp (NM 001126256 and Lsp-t (NM 001043443, were analyzed by a bioinformatics approach according to the sequences of 30K proteins previously reported in the silkworm. Both Slp and Lsp-t shared more than 41% amino acid sequence homology with the reported 30K proteins and displayed a conserved domain consistent with that of lipoprotein-11. Additionally, the cDNA sequences of both Slp and Lsp-t were obtained from the fat bodies of silkworm larvae by reverse transcription polymerase chain reaction. Both genes were expressed in BmN cells using the Bac-to-Bac system. Purified Slp and Lsp-t were added to cultured BmN and human umbilical vein endothelial cells (HUVEC that were treated with H2O2. Both Slp and Lsp-t significantly enhanced the viability and suppressed DNA fragmentation in H2O2 treated BmN and HUVEC cells. This study suggested that Slp and Lsp-t exhibit similar biological activities as their known 30K-protein counterparts and mediate an inhibitory effect against H2O2-induced apoptosis.

  7. 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.

  8. Regulation of dental pulp stem cell's anti-apoptotic ability and proliferation through over-expression of Bcl-2

    OpenAIRE

    Liu, Yuan; 刘源

    2014-01-01

    The pulp organ is retained in the pulp chamber of teeth and maintains the biological and physiological vitality of the surrounding dentin. It works as a biosensor and generates secondary dentine and tertiary dentine to resist tooth abrasion and pathogenic stimuli (Zhang and Yelick, 2010). However, dental pulp is vulnerable to injury (Smulson and Sieraski, 1989). Most people experience some irreversible pulpal diseases during their lifetime. Hence, pulp regeneration is one of the research task...

  9. Dynamin inhibitors induce caspase-mediated apoptosis following cytokinesis failure in human cancer cells and this is blocked by Bcl-2 overexpression

    Directory of Open Access Journals (Sweden)

    Braithwaite Antony W

    2011-06-01

    Full Text Available Abstract Background The aim of both classical (e.g. taxol and targeted anti-mitotic agents (e.g. Aurora kinase inhibitors is to disrupt the mitotic spindle. Such compounds are currently used in the clinic and/or are being tested in clinical trials for cancer treatment. We recently reported a new class of targeted anti-mitotic compounds that do not disrupt the mitotic spindle, but exclusively block completion of cytokinesis. This new class includes MiTMAB and OcTMAB (MiTMABs, which are potent inhibitors of the endocytic protein, dynamin. Like other anti-mitotics, MiTMABs are highly cytotoxic and possess anti-proliferative properties, which appear to be selective for cancer cells. The cellular response following cytokinesis failure and the mechanistic pathway involved is unknown. Results We show that MiTMABs induce cell death specifically following cytokinesis failure via the intrinsic apoptotic pathway. This involves cleavage of caspase-8, -9, -3 and PARP, DNA fragmentation and membrane blebbing. Apoptosis was blocked by the pan-caspase inhibitor, ZVAD, and in HeLa cells stably expressing the anti-apoptotic protein, Bcl-2. This resulted in an accumulation of polyploid cells. Caspases were not cleaved in MiTMAB-treated cells that did not enter mitosis. This is consistent with the model that apoptosis induced by MiTMABs occurs exclusively following cytokinesis failure. Cytokinesis failure induced by cytochalasin B also resulted in apoptosis, suggesting that disruption of this process is generally toxic to cells. Conclusion Collectively, these data indicate that MiTMAB-induced apoptosis is dependent on both polyploidization and specific intracellular signalling components. This suggests that dynamin and potentially other cytokinesis factors are novel targets for development of cancer therapeutics.

  10. Up-regulation of heme oxygenase provides vascular protection in an animal model of diabetes through its antioxidant and antiapoptotic effects.

    Science.gov (United States)

    Kruger, Adam L; Peterson, Stephen J; Schwartzman, Michal L; Fusco, Heidi; McClung, John A; Weiss, Melvin; Shenouda, Sylvia; Goodman, Alvin I; Goligorsky, Michael S; Kappas, Attallah; Abraham, Nader G

    2006-12-01

    Heme oxygenase (HO) plays a critical role in the regulation of cellular oxidative stress. The effects of the reactive oxygen species scavenger ebselen and the HO inducers cobalt protoporphyrin and stannous chloride (SnCl(2)) on HO protein levels and activity, indices of oxidative stress, and the progression of diabetes were examined in the Zucker rat model of type 2 diabetes. The onset of diabetes coincided with an increase in HO-1 protein levels and a paradoxical decrease in HO activity, which was restored by administration of ebselen. Up-regulation of HO-1 expressed in the early development of diabetes produced a decrease in oxidative/nitrosative stress as manifested by decreased levels of 3-nitrotyrosine, superoxide, and cellular heme content. This was accompanied by a decrease in endothelial cell sloughing and reduced blood pressure. Increased HO activity was also associated with a significant increase in the antiapoptotic signaling molecules Bcl-xl and phosphorylation of p38-mitogen-activated protein kinase but no significant increases in Bcl-2 or BAD proteins. In conclusion, 3-nitrotyrosine, cellular heme, and superoxide, promoters of vascular damage, are reduced by HO-1 induction, thereby preserving vascular integrity and protecting cardiac function involving an increase in antiapoptotic proteins. PMID:16959961

  11. Prognostic value of bcl-2 expression among women with breast cancer in Libya.

    Science.gov (United States)

    Ermiah, Eramah; Buhmeida, Abdelbaset; Khaled, Ben Romdhane; Abdalla, Fathi; Salem, Nada; Pyrhönen, Seppo; Collan, Yrjö

    2013-06-01

    We studied the association of the immunohistochemical bcl-2 expression in Libyan breast cancer with clinicopathological variables and patient outcome. Histological samples from 170 previously untreated primary Libyan breast carcinoma patients were examined. In immunohistochemistry, the NCL-L-bcl-2-486 monoclonal antibody was used. Positive expression of bcl-2 was found in 106 patients (62.4 %). The bcl-2 expression was significantly associated with estrogen receptor (p50 years; p=0.04). Histological subtypes and family history of breast cancer did not have significant relationship with bcl-2. Patients with positive expression of bcl-2 had lower recurrence rate than bcl-2-negative patients and better survival after median follow-up of 47 months. Patients with high bcl-2 staining were associated with the best survival. The role of bcl-2 as an independent predictor of disease-specific survival was assessed in a multivariate survival (Cox) analysis, including age, hormonal status, recurrence, histological grade, and clinical stage variables. Bcl-2 (p<0.0001) and clinical stage (p=0.016) were independent predicators of disease-specific survival. For analysis of disease-free survival, the same variables were entered to the model and only bcl-2 proved to be an independent predictor (p=0.002). Patients with positive expression of bcl-2 were associated with low grade of malignancy, with lower recurrence rate, with lower rate of death, and with longer survival time. Bcl-2 is an independent predictor of breast cancer outcome, and it provides useful prognostic information in Libyan breast cancer. Thus, it could be used with classical clinicopathological factors to improve patient selection for therapy.

  12. Allitridi induces apoptosis by affecting Bcl-2 expression and caspase-3 activity in human gastric cancer cells

    Institute of Scientific and Technical Information of China (English)

    Hong LAN; You-yong LU

    2004-01-01

    AIM: To investigate the mechanism of allitridi-induced apoptosis in human gastric cancer cell line BGC823.METHODS: Growth inhibition by allitridi was analyzed using cell growth curve and MTT assay. Apoptotic cells were detected using staining with Hoechst 33342, and confirmed by flow cytometric analysis and DNA fragmentation analysis. The protein expression affected by allitridi was determined using Western blot. The activity of caspase-3 was measured using a fluorescence assay. RESULTS: Allitridi induced apoptosis, and then inhibited cells proliferation in human gastric cancer cell line BGC823. The protein level of Bcl-2 was decreased dramatically,while Bax and p53 were not significantly affected by allitridi. The expression and activity of caspase-3 started to increase after allitridi treatment for 72 h. CONCLUSION: Allitridi induced apoptosis through down-regulation of Bcl-2, and increased caspase-3 expression and its activity.

  13. Dynamical Binding of Hydrogen Bond Surrogate-Derived Bak Helices to Anti-apoptotic Protein Bcl-xL

    OpenAIRE

    Bao, Ju; Dong, Xiao Y.; John Z. H. Zhang; Arora, Paramjit S.

    2009-01-01

    A new peptide modification strategy was recently developed to replace the i to i+4 hydrogen bond of the main chain of an a-helix with a carbon-carbon covalent bond to afford highly stable constrained α-helices, termed Hydrogen Bond Surrogate (HBS) helices. HBS helices that mimic the Bak BH3 domains were experimentally demonstrated to target protein Bcl-xL with high affinity. In this study, molecular dynamics (MD) simulation is used to understand how the covalent modification of the natural Ba...

  14. Electroporation increases antitumoral efficacy of the bcl-2 antisense G3139 and chemotherapy in a human melanoma xenograft

    OpenAIRE

    Baldi Alfonso; D'Angelo Carmen; Scarsella Marco; De Mori Roberta; Biroccio Annamaria; Spugnini Enrico P; Leonetti Carlo

    2011-01-01

    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 ...

  15. Significance of Bcl-2 family in tumor progression and therapy%Bcl-2家族在肿瘤进展和治疗中的意义

    Institute of Scientific and Technical Information of China (English)

    朱园园

    2008-01-01

    Bcl-2 family have dual-regulating effects on cell apoptosis mediated by mitoehondrion. The ratio of pro-apoptosis members and anti-apoptosis members closely correlates with tumorigenesis, drug-resist-ance and prognosis. Therefore,Bcl-2 family become important targets in tumor biotherapy. Many strategies have been applied to tumors treatment targeting Bcl-2 family,such as some biological treatment,short peptides and organic small molecules.%Bcl-2家族对于线粒体途径细胞凋亡具有双重调控作用,其促凋亡蛋白与抑凋亡蛋白的比例与肿瘤形成、肿瘤耐药性的产生及预后密切相关.因此,Bcl-2家族成为肿瘤生物治疗中的重要靶点,针对Bcl-2家族的某些生物治疗手段和短肽、有机小分子等新药被开发应用于Bcl-2高表达肿瘤的治疗.

  16. Altered mitochondria and Bcl-2 expression in the hippocampal CA3 region in a rat model of acute epilepsy

    Institute of Scientific and Technical Information of China (English)

    Jiyan Cheng; Lina Wu; Qiaozhi Wang; Yanfeng Gan; Guangyi Liu; Hong Yu

    2009-01-01

    BACKGROUND: Previous studies have shown that the mitochondrial structure and function are damaged in animal models of epilepsy. In addition, the Bcl-2 protein is capable of regulating mitochondrial stability.OBJECTIVE: To observe and validate changes in mitochondrial structure and Bcl-2 expression, and to analyze these characteristics in the hippocampal CA3 region of rat models of epilepsy. DESIGN, TIME AND SETTING: This randomized, controlled, animal experiment was performed at the Laboratory of Electron Microscopy and Department of Histology and Embryology, Luzhou Medical College between 2007 and 2008.MATERIALS: Coriamyrtin was provided by the Pharmacy Factory of West China University of Medical Sciences. The primary and secondary antibodies were provided by Zhongshan Goldenbridge Biotechnology, Beijing.METHODS: A total of 44 adult, male, Sprague Dawley rats were randomly divided into control (n=11) and epilepsy (n=33) groups. Rats in the epilepsy group were induced by coriamyrtin (50μg/kg), which was injected into the lateral ventricles. The rats were then observed at 3, 6, and 24 hours after epilepsy induction, with 11 rats at each time point. Epilepsy was not induced in rats from the control group.MAIN OUTCOME MEASURES: Pathological changes in the hippocampal CA3 region were observed by light microscopy; Bcl-2 expression was analyzed by immunohistochemistry; and mitochondrial changes in the hippocampus were observed under transmission electron microscopy.RESULTS: (1) The control group displayed very little Bcl-2 protein expression in the hippocampal CA3 region. However, after 3 hours of epilepsy, expression was visible. By 6 hours, expression peaked and then subsequently decreased after 24 hours, but remained higher than the control group (P<0.05). (2) Mitochondria were damaged to varying degrees in the epilepsy groups. For example, mitochondria edema, cristae space increase, and disappearance of mitochondria were apparent. Moreover, mitochondrial damage

  17. Endothelium Expression of Bcl-2 Is Essential for Normal and Pathological Ocular Vascularization

    OpenAIRE

    Ismail S Zaitoun; Johnson, Ryan P.; Jamali, Nasim; Almomani, Reem; Wang, Shoujian; Sheibani, Nader; Sorenson, Christine M.

    2015-01-01

    Bcl–2 is an anti-apoptotic protein with important roles in vascular homeostasis and angiogenesis. Mice globally lacking Bcl–2 (Bcl–2 -/-) are small in stature and succumb to renal failure shortly after weaning as a result of renal hypoplasia/cystic dysplasia. We have shown that Bcl–2 -/- mice displayed attenuated retinal vascular development and neovascularization. In vitro studies indicated that in addition to modulating apoptosis, Bcl–2 expression also impacts endothelial and epithelial cel...

  18. The CORM ALF-186 Mediates Anti-Apoptotic Signaling via an Activation of the p38 MAPK after Ischemia and Reperfusion Injury in Retinal Ganglion Cells

    Science.gov (United States)

    Ulbrich, Felix; Kaufmann, Kai B.; Meske, Alexander; Lagrèze, Wolf A.; Augustynik, Michael; Buerkle, Hartmut; Ramao, Carlos C.; Biermann, Julia

    2016-01-01

    Purpose Ischemia and reperfusion injury may induce apoptosis and lead to sustained tissue damage and loss of function, especially in neuronal organs. While carbon monoxide is known to exert protective effects after various harmful events, the mechanism of carbon monoxide releasing molecules in neuronal tissue has not been investigated yet. We hypothesize that the carbon monoxide releasing molecule (CORM) ALF-186, administered after neuronal ischemia-reperfusion injury (IRI), counteracts retinal apoptosis and its involved signaling pathways and consecutively reduces neuronal tissue damage. Methods IRI was performed in rat´s retinae for 1 hour. The water-soluble CORM ALF-186 (10 mg/kg) was administered intravenously via a tail vein after reperfusion. After 24 and 48 hours, retinal tissue was harvested to analyze mRNA and protein expression of Bcl-2, Bax, Caspase-3, ERK1/2, p38 and JNK. Densities of fluorogold pre-labeled retinal ganglion cells (RGC) were analyzed 7 days after IRI. Immunohistochemistry was performed on retinal cross sections. Results ALF-186 significantly reduced IRI mediated loss of RGC. ALF-186 treatment differentially affected mitogen-activated protein kinases (MAPK) phosphorylation: ALF-186 activated p38 and suppressed ERK1/2 phosphorylation, while JNK remained unchanged. Furthermore, ALF-186 treatment affected mitochondrial apoptosis, decreasing pro-apoptotic Bax and Caspase-3-cleavage, but increasing anti-apoptotic Bcl-2. Inhibition of p38-MAPK using SB203580 reduced ALF-186 mediated anti-apoptotic effects. Conclusion In this study, ALF-186 mediated substantial neuroprotection, affecting intracellular apoptotic signaling, mainly via MAPK p38. CORMs may thus represent a promising therapeutic alternative treating neuronal IRI. PMID:27764224

  19. Human Noxin is an anti-apoptotic protein in response to DNA damage of A549 non-small cell lung carcinoma.

    Science.gov (United States)

    Won, Kyoung-Jae; Im, Joo-Young; Yun, Chae-Ok; Chung, Kyung-Sook; Kim, Young Joo; Lee, Jung-Sun; Jung, Young-Jin; Kim, Bo-Kyung; Song, Kyung Bin; Kim, Young-Ho; Chun, Ho-Kyung; Jung, Kyeong Eun; Kim, Moon-Hee; Won, Misun

    2014-06-01

    Human Noxin (hNoxin, C11Orf82), a homolog of mouse noxin, is highly expressed in colorectal and lung cancer tissues. hNoxin contains a DNA-binding C-domain in RPA1, which mediates DNA metabolic processes, such as DNA replication and DNA repair. Expression of hNoxin is associated with S phase in cancer cells and in normal cells. Expression of hNoxin was induced by ultraviolet (UV) irradiation. Knockdown of hNoxin caused growth inhibition of colorectal and lung cancer cells. The comet assay and western blot analysis revealed that hNoxin knockdown induced apoptosis through activation of p38 mitogen-activated protein kinase (MAPK)/p53 in non-small cell lung carcinoma A549 cells. Furthermore, simultaneous hNoxin knockdown and treatment with DNA-damaging agents, such as camptothecin (CPT) and UV irradiation, enhanced apoptosis, whereas Trichostatin A (TSA) did not. However, transient overexpression of hNoxin rescued cells from DNA damage-induced apoptosis but did not block apoptosis in the absence of DNA damage. These results suggest that hNoxin may be associated with inhibition of apoptosis in response to DNA damage. An adenovirus expressing a short hairpin RNA against hNoxin transcripts significantly suppressed the growth of A549 tumor xenografts, indicating that hNoxin knockdown has in vivo anti-tumor efficacy. Thus, hNoxin is a DNA damage-induced anti-apoptotic protein and potential therapeutic target in cancer.

  20. Icariin Attenuates OGD/R-Induced Autophagy via Bcl-2-Dependent Cross Talk between Apoptosis and Autophagy in PC12 Cells

    Science.gov (United States)

    2016-01-01

    Icariin (ICA), an active component of Epimedium brevicornum Maxim, exerts a variety of neuroprotective effects such as antiapoptosis. However, the mechanisms underlying antiapoptosis of ICA in neurons exposed to oxygen-glucose deprivation and reperfusion (OGD/R) are unclear. The B-cell lymphoma-2 (Bcl-2) protein family plays an important role in the regulation of apoptosis and autophagy through Bcl-2-dependent cross talk. Bcl-2 suppresses apoptosis by binding to Bax and inhibits autophagy by binding to Beclin-1 which is an autophagy related protein. In the present study, MTT result showed that ICA increased cell viability significantly in OGD/R treated PC12 cells (P < 0.01). Results of western blotting analysis showed that ICA increased Bcl-2 expression significantly and decreased expressions of Bax, cleaved Caspase-3, Beclin-1, and LC3-II significantly in OGD/R treated PC12 cells (P < 0.01). These results suggest that ICA protects PC12 cells from OGD/R induced autophagy via Bcl-2-dependent cross talk between apoptosis and autophagy. PMID:27610184

  1. BCL2L13 is a mammalian homolog of the yeast mitophagy receptor Atg32.

    Science.gov (United States)

    Otsu, Kinya; Murakawa, Tomokazu; Yamaguchi, Osamu

    2015-01-01

    Although Atg32 is essential for mitophagy in yeast, no mammalian homolog has been identified. Here, we demonstrate that BCL2L13 (BCL2-like 13 [apoptosis facilitator]) is a functional mammalian homolog of Atg32. First, we hypothesized that a mammalian mitophagy receptor will share certain molecular features with Atg32. Using the molecular profile of Atg32 as a search tool, we screened public databases for novel Atg32 functional homologs and identified BCL2L13. BCL2L13 induces mitochondrial fragmentation and mitophagy in HEK293 cells. In BCL2L13, the BH domains are important for fragmentation, whereas the WXXI motif, an LC3 interacting region, is needed for mitophagy. BCL2L13 induces mitochondrial fragmentation and mitophagy even in the absence of DNM1L/Drp1 and PARK2/Parkin, respectively. BCL2L13 is indispensable for mitochondrial damage-induced fragmentation and mitophagy. Furthermore, BCL2L13 induces mitophagy in Atg32-deficient yeast. Induction and/or phosphorylation of BCL2L13 may regulate its activity. Our findings thus open a new chapter in mitophagy research. PMID:26506896

  2. EFFECT OF TWO NEW BCL-2 ANTISENSES ON DRUG-SENSITIVITY OF CELLS FROMN LEUKEMIA PATIENTS

    Institute of Scientific and Technical Information of China (English)

    LEI Xiao-yong; ZHANG Huan

    2005-01-01

    Objective:To investigate the effect of two antisense oligonucleotides on cell surviving, bcl-2 expression and apoptosis of leukemia cells. Methods: The experimental assays were performed with cell culture, immunochemistry and flowcytometry. Results: The two antisense oligodeoxynucleotides, combined with Vp16 or Ara-c or DNR, were able to decline the survival rate of myeleukemic cells, downregulate bcl-2 gene expression and induce apoptosis of leukemic cells significantly, as compared with Vp16 or Ara-c or DNR alone. Conclusion: It is possible for the two new bcl-2 antisenses to be developed into clinical trials for leukemia and tumor with bcl-2 gene overexpression.

  3. Effects of folic acid on epithelial apoptosis and expression of Bcl-2 and p53 in premalignant gastric lesions

    Institute of Scientific and Technical Information of China (English)

    Da-Zhong Cao; Wei-Hao Sun; Xi-Long Ou; Qian Yu; Ting Yu; You-Zhen Zhang; Zi-Ying Wu; Qi-Ping Xue; Yun-Lin Cheng

    2005-01-01

    AIM: To evaluate the effects of folic acid on epithelial apoptosis and expression of Bcl-2 and p53 in the tissues of premalignant gastric lesions.METHODS: Thirty-eight patients, with premalignant gastric lesions including 18 colonic-type intestinal metaplasia(IM)and 20 mild or moderate dysplasia, were randomly divided into a treatment group (n = 19) receiving folic acid 10 mg thrice daily and a control group (n = 19) receiving sucralfate 1 000 mg thrice daily for 3 mo. All patients undervvent endoscopies and four biopsies were taken prior to treatment and repeated after concluding therapy.Folate concentrations in gastric mucosa were measured with chemiluminescent enzyme immunoassay. Epithelial apoptosis and the expression of Bcl-2 and p53 protein in gastric mucosa were detected with flow cytometric assay.RESULTS: The mean of folate concentration in gastric mucosa was 9.03±3.37 μg/g wet wt in the folic acid treatment group, which was significantly higher than 6.83±3.02 μg/g wet wt in the control group. Both the epithelial apoptosis rate and the tumor suppressor p53expression in gastric mucosa significantly increased after folic acid treatment. In contrast, the expression of Bcl-2oncogene protein decreased after folic acid therapy.CONCLUSION: These data indicate that folic acid may play an important role in the chemoprevention of gastric carcinogenesis by enhancing gastric epithelial apoptosis in the patients with premalignant lesions.

  4. Effect of hyperbaric oxygen preconditioning on the expressions of B cell lymphoma/lewkmia-2 and Bcl-2 associated X protein in the brain tissue of rats with decompression sickness%高压氧预处理对减压病大鼠脑组织B细胞淋巴瘤/白血病基因-2蛋白及相关X蛋白表达的影响

    Institute of Scientific and Technical Information of China (English)

    李娅; 岳荣; 王文岚; 薛莉; 任杰; 谢小萍; 迪力达尔; 李金声

    2014-01-01

    目的 探讨高压氧(hyperbaric oxygen,HBO)预处理对减压病大鼠脑组织B细胞淋巴瘤/白血病基因-2蛋白(B cell lymphoma/lewkmia-2,Bcl-2)及相关X蛋白(Bcl-2 associated X protein,Bax)、半胱氨酸天冬氨酸蛋白酶-3蛋白(cysteine aspartic acid specific protease-3,Caspase-3)表达的影响.方法 健康雄性SD大鼠72只,采用数字表法随机分为正常对照组(对照组)、高压氧预处理组(HBO组)、减压病组(DCS组),每组分别设置4个观察时间点(1、5、7、10 d),每个时间点(亚组)6只.建立大鼠减压病模型,HE染色观察减压病后脑组织病理变化,免疫组织化学染色观察各组脑组织Bcl-2、Bax、Caspase-3 的表达.结果 (1) HBO组与DCS组脑组织皮层病情分级为轻度~中度(1~3级).(2)HE染色发现,DCS组大鼠大脑皮层区出现大片疏松区,皮层与海马神经元细胞呈三角形变性坏死,细胞萎缩、体积缩小变性,染色质浓缩甚至碎裂,HBO组神经元变性坏死明显减轻.(3)1、5、7d时,DCS组脑组织皮层Bcl-2阳性细胞数分别为(89.5±15.60)、(176.4±10.22)、(265.52±15.74)个,与对照组(408.67 ±29.57)个相比明显减少,差异均有统计学意义(P<0.01);HBO组[脑组织皮层阳性细胞数分别为(179.64±12.21)、(253.91±14.00)、(341.15±13.52)个],较DCS组明显增加,差异均有统计学意义(P<0.05).1、5、7d时,DCS组脑组织皮层Bax阳性细胞数分别为(389.56±18.62)、(337.04±14.85)、(176.41±20.75)个,Caspase-3阳性细胞数分别为(495.64 ±21.03)、(283.04±13.12)、(352.41 ±21.34)个,较对照组1d时[脑组织皮层Bax和Caspase-3分别为(98.64±14.25)、(106.20±14.64)个]明显增加.HBO组Bax阳性细胞数分别为(313.54±21.02)、(253.05±13.60)、(129.03±12.85)个,Caspase-3分别为(429.43±14.08)、(228.05 ±13.60)、(301.02±15.79)个,较DCS组明显减少,差异均有统计学意义(P<0.05).DCS组Bcl-2/Bax值较对照组明显降低,HBO组Bcl-2/Bax值较DCS组明显升高,

  5. Exogenous phosphatidylethanolamine induces apoptosis of human hepatoma HepG2 cells via the bcl-2/bax pathway

    Institute of Scientific and Technical Information of China (English)

    Yu Yao; Chen Huang; Zong-Fang Li; Ai-Ying Wang; Li-Ying Liu; Xiao-Ge Zhao; Yu Luo; Lei Ni; Wang-Gang Zhang; Tu-Sheng Song

    2009-01-01

    AIM: To investigate the signaling pathways implicated in phosphatidylethanolamine (PE)-induced apoptosis of human hepatoma HepG2 cells. METHODS: Inhibitory effects of PE on human hepatoma HepG2 cells were detected by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Cell cycle, apoptosis and mitochondrial transmembrane potential (ΔΨm) were analyzed by flow cytometry. Immunocytochemical assay and Western blotting were used to examine Bcl-2, Bax and caspase-3 protein levels in HepG2 cells treated with PE. RESULTS: PE inhibited the growth of HepG2 cells in a dose- and time- dependent manner. It did not affect the cell cycle, but induced apoptosis. PE significantly decreased ΔΨm at 0.25, 0.5 and 1 mmol/L, respectively, suggesting that PE induces cell apoptosis by decreasing the mitochondrial transmembrane potential. The Bcl-2 expression level induced by different concentrations of PE was lower than that in control groups. However, the Bax expression level induced by PE was higher than that in the control group. Meanwhile, PE increased the caspase-3 expression in a dose- and time-dependent manner. CONCLUSION: Exogenous PE induces apoptosis of human hepatoma HepG2 cells via the bcl-2/bax pathway.

  6. Intermittent hypoxia attenuates ischemia/reperfusion induced apoptosis in cardiac myocytes via regulating Bcl-2/Bax expression

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Intermittent hypoxia has been shown to provide myocardial protection against ishemia/reperfusion-induced injury.Cardiac myocyte loss through apoptosis has been reported in ischemia/reperfusion injury. Our aim was to investigate whether intermittent hypoxia could attenuate ischemia/reperfusion-induced apoptosis in cardiac myocytes and its potential mechanisms. Adult male Sprague-Dawley rats were exposed to hypoxia simulated 5000 m in a hypobaric chamber for 6 h/day, lasting 42 days. Normoxia group rats were kept under normoxic conditions. Isolated perfused hearts from both groups were subjected to 30 min of global ischemia followed by 60 min reperfusion.Incidence of apoptosis in cardiac myocytes was determined by terminal deoxynucleotidyl transferase mediated dUTP nick end labeling (TUNEL) and DNA agarose gel electrophoresis. Expressions of apoptosis related proteins,Bax and Bcl-2, in cytosolic and membrane fraction were detected by Western Blotting. After ischemia/reperfusion,enhanced recovery of cardiac function was observed in intermittent hypoxia hearts compared with normoxia group.Ischemia/reperfusion-induced apoptosis, as evidenced by TUNEL-positive nuclei and DNA fragmentation, was significantly reduced in intermittent hypoxia group compared with normoxia group. After ischemia/reperfusion,expression of Bax in both cytosolic and membrane fractions was decreased in intermittent hypoxia hearts compared with normoxia group. Although ischemia/reperfusion did not induce changes in the level of Bcl-2 expression in cytosolic fraction between intermittent hypoxia and normoxia groups, the expression of Bcl-2 in membrane fraction was upregulated in intermittent hypoxia group compared with normoxia group. These results indicated that the cardioprotection of intermittent hypoxia against ischemia/reperfusion injury appears to be in part due to reduce myocardial apoptosis. Intermittent hypoxia attenuated ischemia/reperfusion-induced apoptosis via increasing the ratio of Bcl

  7. Targeting glutamine metabolism in multiple myeloma enhances BIM binding to BCL-2 eliciting synthetic lethality to venetoclax.

    Science.gov (United States)

    Bajpai, R; Matulis, S M; Wei, C; Nooka, A K; Von Hollen, H E; Lonial, S; Boise, L H; Shanmugam, M

    2016-07-28

    Multiple myeloma (MM) is a plasma cell malignancy that is largely incurable due to development of resistance to therapy-elicited cell death. Nutrients are intricately connected to maintenance of cellular viability in part by inhibition of apoptosis. We were interested to determine if examination of metabolic regulation of BCL-2 proteins may provide insight on alternative routes to engage apoptosis. MM cells are reliant on glucose and glutamine and withdrawal of either nutrient is associated with varying levels of apoptosis. We and others have demonstrated that glucose maintains levels of key resistance-promoting BCL-2 family member, myeloid cell leukemic factor 1 (MCL-1). Cells continuing to survive in the absence of glucose or glutamine were found to maintain expression of MCL-1 but importantly induce pro-apoptotic BIM expression. One potential mechanism for continued survival despite induction of BIM could be due to binding and sequestration of BIM to alternate pro-survival BCL-2 members. Our investigation revealed that cells surviving glutamine withdrawal in particular, enhance expression and binding of BIM to BCL-2, consequently sensitizing these cells to the BH3 mimetic venetoclax. Glutamine deprivation-driven sensitization to venetoclax can be reversed by metabolic supplementation with TCA cycle intermediate α-ketoglutarate. Inhibition of glucose metabolism with the GLUT4 inhibitor ritonavir elicits variable cytotoxicity in MM that is marginally enhanced with venetoclax treatment, however, targeting glutamine metabolism with 6-diazo-5-oxo-l-norleucine uniformly sensitized MM cell lines and relapse/refractory patient samples to venetoclax. Our studies reveal a potent therapeutic strategy of metabolically driven synthetic lethality involving targeting glutamine metabolism for sensitization to venetoclax in MM. PMID:26640142

  8. The effect of radiation on bcl-2 and bax in hyperplastic prostatic tissues

    International Nuclear Information System (INIS)

    Aim: To investigate the expressions of bcl-2 and bax in benign prostatic hyperplasia (BPH) and the effect of β-rays on bcl-2 and bax. Methods: The expressions of bcl-2 and bax are studied by means of immunohistochemical method in 9 normal prostate (NP) and 15 BPH and 35 patients treated with 90Sr/90Y Prostatic Hyperplasia Applicator. Results: The expressions of bcl-2 in epithelia of NP and BPH are higher than that in stroma P<0.01=. The expressions of bcl-2 in epithelia and stroma of BPH are higher than that in NP P<0.01=. The expressions of bax in epithelia of NP are higher than that in BPH P<0.05=. However ,the expressions of bcl-2 in epithelia and stroma of BPH are higher than bax P<0.01 =. Compared with the control group, the expressions of bcl-2 in epithelia and stroma of BPH treated with 90Sr/90Y Prostatic Hyperplasia Applicator decreased and the expressions of bax increased P<0.01=. Conclusion: bcl-2 gene and bax gene play an important role in the regulation of prostatic apoptosis and the treatment of β-rays can accelerate the apoptosis of prostatic tissues. (authors)

  9. 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

    2000-01-01

    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

  10. Amelioration of apoptotic events in the skeletal muscle of intra-nigrally rotenone-infused Parkinsonian rats by Morinda citrifolia--up-regulation of Bcl-2 and blockage of cytochrome c release.

    Science.gov (United States)

    Narasimhan, Kishore Kumar S; Paul, Liya; Sathyamoorthy, Yogesh Kanna; Srinivasan, Ashokkumar; Chakrapani, Lakshmi Narasimhan; Singh, Abhilasha; Ravi, Divya Bhavani; Krishnan, Thulasi Raman; Velusamy, Prema; Kaliappan, Kathiravan; Radhakrishnan, Rameshkumar; Periandavan, Kalaiselvi

    2016-02-01

    Parkinson's disease is a progressive neurodegenerative movement disorder with the cardinal symptoms of bradykinesia, resting tremor, rigidity, and postural instability, which lead to abnormal movements and lack of activity, which in turn cause muscular damage. Even though studies have been carried out to elucidate the causative factors that lead to muscular damage in Parkinson's disease, apoptotic events that occur in the skeletal muscle and a therapeutical approach to culminate the muscular damage have not been extensively studied. Thus, this study evaluates the impact of rotenone-induced SNPc lesions on skeletal muscle apoptosis and the efficacy of an ethyl acetate extract of Morinda citrifolia in safeguarding the myocytes. Biochemical assays along with apoptotic markers studied by immunoblot and reverse transcription-polymerase chain reaction in the current study revealed that the supplementation of Morinda citrifolia significantly reverted alterations in both biochemical and histological parameters in rotenone-infused PD rats. Treatment with Morinda citrifolia also reduced the expression of pro-apoptotic proteins Bax, caspase-3 and caspase-9 and blocked the release of cytochrome c from mitochondria induced by rotenone. In addition, it augmented the expression of Bcl2 both transcriptionally and translationally. Thus, this preliminary study paves a way to show that the antioxidant and anti-apoptotic activities of Morinda citrifolia can be exploited to alleviate skeletal muscle damage induced by Parkinsonism.

  11. The correlation research on the expression of Bcl-2,Bax and eNOS in the ICR mice testicles%Bcl-2和Bax在ICR小鼠睾丸中的表达及与eNOS的关联性研究

    Institute of Scientific and Technical Information of China (English)

    左俐俊; 任亚萍; 赵玮; 宋婉玲

    2016-01-01

    目的 探讨B淋巴细胞瘤/白血病-2 ( Bcl-2 )和Bcl-2相关X蛋白( Bax)在雄性ICR小鼠睾丸中的表达及与内皮型一氧化氮合酶( eNOS)的联系和意义. 方法 30只(分别为4、8、12周龄,各10只)健康雄性ICR小鼠,分为性成熟前(4周龄组)、性成熟(8周龄组)、性成熟后(12周龄组),取左侧睾丸经石蜡切片,免疫组化法检测小鼠睾丸中 eNOS、Bcl-2和Bax蛋白的表达分布情况;取右侧睾丸,Western blot法检测eNOS、Bcl-2 和 Bax的表达情况. 结果 Bcl-2 在睾丸间质细胞高表达,Bax在生精上皮有表达;8周龄小鼠睾丸间质细胞Bcl-2表达明显高于4、12周龄组,且8周龄组小鼠Bax表达明显低于4、12周龄组小鼠( P<0. 05 );4周龄组小鼠睾丸eNOS蛋白表达明显高于8、12 周龄组( P <0. 01 ).结论 Bcl-2、Bax与eNOS在睾丸间质细胞的表达并没有直接的相关性,提示NO或许未直接参与睾丸间质细胞的凋亡活动.%Objective To explore the expression and significance of the B-cell lymphoma/leukemia-2(Bcl-2),Bcl-2 associated X protein ( Bax ) in ICR mice testicles, and the correlation with endothelial nitric oxide synthase (eNOS). Methods 30 (4 weeks,8 weeks and 12 weeks respectively,each 10) healthy male ICR mice were divid-ed into three groups randomly:young period,adolescent period and the period of sexual maturity. Paraffin section of the left testis was made, the expressions of the Bcl-2,Bax and eNOS in the testis of male mice were observed with immunohistochemical method. Then Western blot was carried out to screen the protein of Bcl-2,Bax and eNOS in the right side of the mice testicles. Results The Bcl-2 highly appeared in leydig cells,while Bax in rawhide cell. The expression of Bcl-2 in the 8-week-old mice leydig cells was significantly higher than that in 4 or 12-week-old groups. The protein levels of Bax in the 8-week-old mice was lower than that in 4 or 12-week-old group ( P <0. 05). Besides,the expression of eNOS in 4-week

  12. The Protective Properties of the Strawberry (Fragaria ananassa) against Carbon Tetrachloride-Induced Hepatotoxicity in Rats Mediated by Anti-Apoptotic and Upregulation of Antioxidant Genes Expression Effects

    Science.gov (United States)

    Hamed, Sherifa S.; AL-Yhya, Nouf A.; El-Khadragy, Manal F.; Al-Olayan, Ebtesam M.; Alajmi, Reem A.; Hassan, Zeinab K.; Hassan, Salwa B.; Abdel Moneim, Ahmed E.

    2016-01-01

    The strawberry (Fragaria ananassa) has been extensively used to treat a wide range of ailments in many cultures. The present study was aimed at evaluating the hepatoprotective effect of strawberry juice on experimentally induced liver injury in rats. To this end, rats were introperitoneally injected with carbon tetrachloride (CCl4) with or without strawberry juice supplementation for 12 weeks and the hepatoprotective effect of strawberry was assessed by measuring serum liver enzyme markers, hepatic tissue redox status and apoptotic markers with various techniques including biochemistry, ELISA, quantitative PCR assays and histochemistry. The hepatoprotective effect of the strawberry was evident by preventing CCl4-induced increase in liver enzymes levels. Determination of oxidative balance showed that strawberry treatment significantly blunted CCl4-induced increase in oxidative stress markers and decrease in enzymatic and non-enzymatic molecules in hepatic tissue. Furthermore, strawberry supplementation enhanced the anti-apoptotic protein, Bcl-2, and restrained the pro-apoptotic proteins Bax and caspase-3 with a marked reduction in collagen areas in hepatic tissue. These findings demonstrated that strawberry (F. ananassa) juice possessed antioxidant, anti-apoptotic and anti-fibrotic properties, probably mediated by the presence of polyphenols and flavonoids compounds. PMID:27547187

  13. Expression of Inducible Nitric Oxide Synthase, p53 and Bcl-2 in Gastric Precancerous and Cancerous Lesions: Correlation with Clinical Features

    Institute of Scientific and Technical Information of China (English)

    Tao Cui; Zu'an Zhu; Ying Liu; Qingyan Kong; Sujuan Fei

    2006-01-01

    OBJECTIVE To explore the expression of inducible nitric oxide synthase(iNOS), p53 and bcl-2 in gastric precancerous and cancerous lesions and to examine the expression of these proteins in relation to clinical features.METHODS The expressions of iNOS, p53 and bcl-2 proteins in gastric precancerous and cancerous lesions and their correlations with the clinical features were determined using immunohistochemical assays (Power VisionTM two-step method) on 84 gastric carcinomas and 54 gastric atypical hyperplastic tissues. Apoptotic cells were evaluated by terminal deoxynucleotidyl transferase- mediated dUTP-biotin nick-end labeling (TUNEL).RESULTS Expression of iNOS, p53 and bcl-2 was significantly higher in gastric carcinoma (GC) tissues than in gastric atypical hyperplastic tissues. Among the 84 carcinomas, the expression of p53 was observed in 50 (59.52%), bcl-2 in 43 (51.19%), and iNOS in 65 (77.58%). Overexpression of iNOS and bcl-2 in gastrlc carcinoma was related to tumor size and iNOS was related to the presence of lymph node metastasis (P<0.05). The expression of proteins did not correlate with age, sex, stage of disease, or differentiation. Expression of iNOS in gastric carcinoma tissues was positively correlated with bcl-2 expression (χ2=8.926, P=0.003),and also with p53 expression (χ2= 5.2430, P= 0.022). The mean apoptotic indexes (Al) were 1.29%±0.50 in low-grade atypical hyperplasia (LG),0.96%±0.36 in high-grade atypical hyperplasia (HG) and 0.70%±0.43 in GC, with the difference being significant between LG, HG and GC (P<0.05). There was a significant positive correlation between iNOS expression and the Al in GC (t=3.0815, P=0.0028).CONCLUSION iNOS was expressed in the majority of gastric carcinoma tissues and correlated with cellular apoptosis associated with p53 and bcl-2 expression. iNOS overexpression is closely associated with p53 and bcl-2 accumulation status. iNOS may play a synergistic role in the pathogenesis of GC.

  14. Fas and Bcl-2 Expression on T Lymphocyte Subsets in the Peripheral Blood of Relapsing Patients with Condyloma Acuminatum

    Institute of Scientific and Technical Information of China (English)

    顾军; 范清源; 高春芳; 代夫; 郑茂荣

    2003-01-01

    Objective: To study the expression of Fas and Bcl-2 proteins on T lymphocyte subsets in the peripheral blood of relapsing patients with condyloma acuminatum(CA) and healthy controls.Methods: Flow cytometry (permeabization and staining procedure with conjugated antibodies) was used.Results: We observed that the expression of Fas protein on CD4+ T lymphocyte subset of CA patients was significantly higher than that of healthy controls( P<0.01 ).Conclusions: Increased expression of Fas proteinon CD4+ T lymphocyte subset may be a cause of de-creased percentage of CD4+ T lymphocyte subset. This induces the increased ratio of CD4+/CD8+.

  15. Inhibition of Bcl-2 expression by a novel tumor-specific RNA interference system increases chemosensitivity to 5-fluorouracil in Hela cells

    Institute of Scientific and Technical Information of China (English)

    Sheng-lin HUANG; Yi WU; Hai YU; Ping ZHANG; Xing-qian ZHANG; Lei YING; Han-fang ZHAO

    2006-01-01

    Aim: RNA interference (RNAi) has been proposed as a potential treatment for cancer, but the lack of cellular targets limits its use in cancer gene therapy. No current technology has achieved direct tumor-specific gene silencing using RNAi.In the present study we attempt to develop a tumor-specific RNAi system using the human telomerase reverse transcriptase (hTERT) promoter; furthermore, we analyzed its inhibitive effect on Bcl-2 expression. Methods: The vectors containing a small hairpin RNA (shRNA) to target exogenous reporters [firefly luciferase and enhanced green fluorescent protein (EGFP)] and endogenous gene (Bcl-2)were constructed. Luciferase expression was determined by dual luciferase assay.Reverse transcription-polymerase chain reaction (RT-PCR), fluorescence microscopy and fluorescence-activated cell sorting (FACS) were used to measure EGFP expression. Inhibition of Bcl-2 was evaluated by RT-PCR and Western blotting.Cell proliferation and viability were measured by using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay. FACS was used to analyze the cell cycle distribution profile. Results: We showed that with the hTERT promoter directly driving shRNA transcription, expression of the exogenous reporters (LUC and EGFP) in tumor cells, but not normal cells, was specifically inhibited in vitro. The hTERT promoter-driven shRNA also depressed the expression of Bcl-2. Inhibition of Bcl-2 did not affect cell proliferation, but increased the chemosensitivity of HeLa cells to 5-fluorouracil. Conclusion: The present study describes an efficient RNAi system for gene silencing that is specific to tumor cells using the hTERT promoter. Suppression of Bcl-2 by using this system sensitized HeLa cells to 5-fluorouracil. This system may be useful for RNAi therapy.

  16. Depletion of Bcl-2 by an antisense oligonucleotide induces apoptosis accompanied by oxidation and externalization of phosphatidylserine in NCI-H226 lung carcinoma cells.

    Science.gov (United States)

    Koty, Patrick P; Tyurina, Yulia Y; Tyurin, Vladimir A; Li, Shang-Xi; Kagan, Valerian E

    2002-01-01

    Oxidant-induced apoptosis involves oxidation of many different and essential molecules including phospholipids. As a result of this non-specific oxidation, any signaling role of a particular phospholipid-class of molecules is difficult to elucidate. To determine whether preferential oxidation of phosphatidylserine (PS) is an early event in apoptotic signaling related to PS externalization and is independent of direct oxidant exposure, we chose a genetic-based induction of apoptosis. Apoptosis was induced in the lung cancer cell line NCI-H226 by decreasing the amount of Bcl-2 protein expression by preventing the translation of bcl-2 mRNA using an antisense bcl-2 oligonucleotide. Peroxidation of phospholipids was assayed using a fluorescent technique based on metabolic integration of an oxidation-sensitive and fluorescent fatty acid, cis-parinaric acid (PnA), into cellular phospholipids and subsequent HPLC separation of cis-PnA-labeled phospholipids. We found a decrease in Bcl-2 was associated with a selective oxidation of PS in a sub-population of the cells with externalized PS. No significant difference in oxidation of cis-PnA-labeled phospholipids was observed in cells treated with medium alone or a nonsense oligonucleotide. Treatment with either nonsensc or antisense bcl-2 oligonucleotides was not associated with changes in the pattern of individual phospholipid classes as determined by HPTLC. These metabolic and topographical changes in PS arrangement in plasma membrane appear to be early responses to antisense bcl-2 exposure that trigger a PS-dependent apoptotic signaling pathway. This observed externalization of PS may facilitate the 'labeling' of apoptotic cells for recognition by macrophage scavenger receptors and subsequent phagocytic clearance. PMID:12162425

  17. The distinct role of guanine nucleotide exchange factor Vav1 in Bcl-2 transcription and apoptosis inhibition in Jurkat leukemia T cells

    Institute of Scientific and Technical Information of China (English)

    Jie YIN; Ya-juan WAN; Shi-yang LI; Ming-juan DU; Cui-zhu ZHANG; Xing-long ZHOU; You-jia CAO

    2011-01-01

    Aim: To investigate a novel function of proto-oncogene Vavl in the apoptosis of human leukemia Jurkat cells.Methods: Jurkat cells,Jurkat-derived vavl-null cells(J.Vavl)and Vavl-reconstituted J.WT cells were treated with a Fas agonist antibody,IgM clone CH11.Apoptosis was determined using propidium iodide(PI)staining,Annexin-V staining,DNA fragmentation,cleavage of caspase 3/caspase 8,and poly(ADP-ribose)polymerase(PARP).Mitochondria transmembrane potential(Δψm)was measured using DiOC6(3)staining.Transcription and expression of the Bcl-2 family of proteins were evaluated using semi-quantitative RT-PCR and Western blot,respectively.Bcl-2 promoter activity was analyzed using luciferase reporter assays.Results: Cells lacking Vav1 were more sensitive to Fas-mediated apoptosis than Jurkat and J.WT cells.J.Vav1 cells lost mitochondria transmembrane potential(Δψm)more rapidly upon Fas induction.These phenotypes could be rescued by re-expression of Vav1 in J.Vav1 cells.The expression of Vav1 increased the transcription of pro-survival Bcl-2.The guanine nucleotide exchange activity of Vav1was required for enhancing Bcl-2 promoter activity,and the Vav1 downstream substrate,small GTPase Rac2,was likely involved in the control of Bcl-2 expression.Conclusion: Vav1 protects Jurkat cells from Fas-mediated apoptosis by promoting Bcl-2 transcription through its GEF activity.

  18. Gli1 maintains cell survival by up-regulating IGFBP6 and Bcl-2 through promoter regions in parallel manner in pancreatic cancer cells

    Directory of Open Access Journals (Sweden)

    Xu Xuan-Fu

    2009-01-01

    Full Text Available Background: Aberrant activation of Hedgehog (Hh signaling pathway has been reported to be related to malignant biological behavior of pancreatic cancer but its mechanism is unclear yet. Since IGF pathway and Bcl-2 family are involved in proliferation and apoptosis of pancreatic cancer cells, we hypothesize that they are possibly associated with Hh pathway. Materials and Methods: We studied the relationship of Shh-Gli1 signaling pathway with proliferation and apoptosis of pancreatic cancer cells and the regulation of transcription factor Gli1 to insulin-like growth factor binding protein 6 (IGFBP6 and Bcl-2 genes at the level of transcription. Results: Sonic hedgehog (Shh, Smoothened (Smo, patched and Gli1 were expressed in pancreatic cancer cells. Cyclopamine inhibited cell proliferation at low concentration and induced apoptosis at high concentration. Effect of RNA interference (RNAi for Gli1 to cell survival is mainly due to proliferation inhibition though involved in apoptosis. The transcription factor Gli1 bound to promoter regions of Bcl-2 and IGFBP6 genes and the levels of IGFBP6, proliferating cell nuclear antigen (PCNA and Bcl-2 messenger RNA (mRNA were decreased as well as Gli1 mRNA significantly by cyclopamine or RNAi in cultured pancreatic cancer cells (p < 0.01. Finally PCNA, IGFBP6 and Bcl-2 mRNA were upregulated as well as Shh or Gli1 in pancreatic cancer tissues (p < 0.01. Conclusions: Our study reveals that Gli1 maintained cell survival by binding the promoter regions and facilitating transcription of IGFBP6 and Bcl-2 genes in a parallel manner in pancreatic cancer cells and suggests it may be one of the mechanisms of Shh-Gli1 signaling pathway in pancreatic cancer.

  19. 地西他滨对胃癌SGC7901细胞系BCL2L10基因表达及其生物学特性的影响%Effects of decitabine on the expression of BCL2L10 and biological behaviors in gastric cancer cell line SGC7901

    Institute of Scientific and Technical Information of China (English)

    孔秀敏; 王晓兰

    2013-01-01

    目的:观察抗肿瘤新药地西他滨对胃癌细胞系SGC7901中抗凋亡基因BCL2L10启动子甲基化及基因表达的影响,探讨其对胃癌细胞生物学行为的影响.方法:用浓度为5、10 μmol/L的地西他滨处理胃癌细胞SGC7901,应用甲基化特异性PCR检测BCL2L10基因启动子甲基化状况,应用免疫印迹检测BCL2L10蛋白表达,MTS法检测细胞增殖情况,annexin V-FITC/PI双染检测细胞凋亡,siRNA干扰BCL2L10表达以探讨地西他滨可能的作用机制.结果:SGC7901细胞中BCL2L10基因以启动子甲基化方式失活,地西他滨呈剂量依赖方式逆转其甲基化程度,恢复基因表达,同时可见细胞增殖受到抑制,凋亡比例增加,而干扰BCL2L10可对抗地西他滨的抗肿瘤效应.结论:地西他滨可通过逆转胃癌SGC7901细胞系BCL2L10启动子甲基化而恢复其表达,表现出抗肿瘤活性,具有潜在的临床应用价值.%Objective:To investigate the impact of decitabine on the methylation of BCL2L10 promoter and gene expression in gastric cancer cell line SGC7901,and to explore its effects on the oncological behavior of gastric cancer.Methods:SGC7901 cells were treated with decitabine at the concentration of 5μmol/L and 10μmol/L.The methylation status of BCL2L10 promoter was detected by methylation-specific PCR,and the protein expression was detected by immunoblotting.The proliferation of SGC7901 cells was measured with MTS reagent,and the apoptosis was examined by annexin V-FITC/PI double staining.BLC2L10-specific siRNA was constructed and transfected into SGC7901 cells to further explore the potential mechanisms of decitabine.Results:The promoter of BCL2L10 in SGC7901 cells was hypermethylated and its expression was completely lost.Decitabine treatment reversed the methylation status of BCL2L10 and restored its protein expression in a dose-dependent manner.Meanwhile,the proliferation of SGC7901 was inhibited by decitabine treatment,whereas the apoptotic rate was

  20. Zebrafish bcl2l is a survival factor in thyroid development.

    Science.gov (United States)

    Porreca, Immacolata; De Felice, Elena; Fagman, Henrik; Di Lauro, Roberto; Sordino, Paolo

    2012-06-15

    Regulated cell death, defined in morphological terms as apoptosis, is crucial for organ morphogenesis. While differentiation of the thyroid gland has been extensively studied, nothing is yet known about the survival mechanisms involved in the development of this endocrine gland. Using the zebrafish model system, we aim to understand whether genes belonging to the Bcl-2 family that control apoptosis are implicated in regulation of cell survival during thyroid development. Evidence of strong Bcl-2 gene expression in mouse thyroid precursors prompted us to investigate the functions played by its zebrafish homologs during thyroid development. We show that the bcl2-like (bcl2l) gene is expressed in the zebrafish thyroid primordium. Morpholino-mediated knockdown and mutant analyses revealed that bcl2l is crucial for thyroid cell survival and that this function is tightly modulated by the transcription factors pax2a, nk2.1a and hhex. Also, the bcl2l gene appears to control a caspase-3-dependent apoptotic mechanism during thyroid development. Thyroid precursor cells require an actively maintained survival mechanism to properly proceed through development. The bcl2l gene operates in the inhibition of cell death under direct regulation of a thyroid specific set of transcription factors. This is the first demonstration of an active mechanism to ensure survival of the thyroid primordium during morphogenesis.