WorldWideScience

Sample records for calnexin regulates apoptosis

  1. Purification and characterization of a soluble calnexin from human placenta

    DEFF Research Database (Denmark)

    Olsen, Dorthe T; Peng, Li; Træholt, Sofie D;

    2013-01-01

    Calreticulin (Crt) and calnexin (Cnx) are homologous endoplasmic reticulum (ER) chaperones involved in protein folding and quality control. Crt is a soluble ER luminal Mr 46 kDa protein and Cnx is a Mr 67kDa ER membrane protein. During purification of Crt from human placenta a soluble form of Cnx...

  2. The evolutionary history of calreticulin and calnexin genes in green plants.

    Science.gov (United States)

    Del Bem, Luiz Eduardo V

    2011-02-01

    Calreticulin and calnexin are Ca(2+)-binding chaperones localized in the endoplasmic reticulum of eukaryotes acting in glycoprotein folding quality control and Ca(2+) homeostasis. The evolutionary histories of calreticulin and calnexin gene families were inferred by comprehensive phylogenetic analyses using 18 completed genomes and ESTs covering the major green plants groups, from green algae to angiosperms. Calreticulin and calnexin possibly share a common origin, and both proteins are present along all green plants lineages. The calreticulin founder gene within green plants duplicated in early tracheophytes leading to two possible groups of orthologs with specialized functions, followed by lineage-specific gene duplications in spermatophytes. Calnexin founder gene in land plants was inherited from basal green algae during evolution in a very conservative copy number. A comprehensive classification in possible groups of orthologs and a catalog of calreticulin and calnexin genes from green plants are provided.

  3. Apoptosis signal-regulating kinase 1 mediates denbinobin-induced apoptosis in human lung adenocarcinoma cells

    Directory of Open Access Journals (Sweden)

    Pan Shiow-Lin

    2009-05-01

    Full Text Available Abstract In the present study, we explore the role of apoptosis signal-regulating kinase 1 (ASK1 in denbinobin-induced apoptosis in human lung adenocarcinoma (A549 cells. Denbinobin-induced cell apoptosis was attenuated by an ASK1 dominant-negative mutant (ASK1DN, two antioxidants (N-acetyl-L-cysteine (NAC and glutathione (GSH, a c-Jun N-terminal kinase (JNK inhibitor (SP600125, and an activator protein-1 (AP-1 inhibitor (curcumin. Treatment of A549 cells with denbinobin caused increases in ASK1 activity and reactive oxygen species (ROS production, and these effects were inhibited by NAC and GSH. Stimulation of A549 cells with denbinobin caused JNK activation; this effect was markedly inhibited by NAC, GSH, and ASK1DN. Denbinobin induced c-Jun phosphorylation, the formation of an AP-1-specific DNA-protein complex, and Bim expression. Bim knockdown using a bim short interfering RNA strategy also reduced denbinobin-induced A549 cell apoptosis. The denbinobin-mediated increases in c-Jun phosphorylation and Bim expression were inhibited by NAC, GSH, SP600125, ASK1DN, JNK1DN, and JNK2DN. These results suggest that denbinobin might activate ASK1 through ROS production to cause JNK/AP-1 activation, which in turn induces Bim expression, and ultimately results in A549 cell apoptosis.

  4. Apoptosis in cancer : regulation and prognostic value

    NARCIS (Netherlands)

    Bruin, Elizabeth Cornelia de

    2008-01-01

    For a tumor cell to propagate, it must survive extremely stressful conditions that would normally trigger the cell to die. Cancer cells however survive, probably due to evasion of the apoptotic cell death pathway. It follows that a detailed understanding of the regulation of the apoptotic pathways i

  5. TNFα PRODUCTION AND APOPTOSIS REGULATION IN VIRAL HEPATITIS TYPE C

    Directory of Open Access Journals (Sweden)

    V. V. Novitsky

    2005-01-01

    Full Text Available Abstract. Chronical course of infection caused by hepatitis C virus is accompanied by increase Fas-positive lymphocytes of peripheral blood. Cultivation of agglutinin-stimulated mononuclear blood cells of patients with chronic hepatitis C revealed inhibition of apoptotic reactions of blood lymphocytes. This fact correlated with decrease in production of TNFα and accelerated synthesis of soluble receptor for this cytokine. We suggest a virus-specific influence on apoptosis regulation of target cells.

  6. Cyclophilin D regulates necrosis, but not apoptosis, of murine eosinophils.

    Science.gov (United States)

    Zhu, Xiang; Hogan, Simon P; Molkentin, Jeffery D; Zimmermann, Nives

    2016-04-15

    Eosinophil degranulation and clusters of free extracellular granules are frequently observed in diverse diseases, including atopic dermatitis, nasal polyposis, and eosinophilic esophagitis. Whether these intact granules are released by necrosis or a biochemically mediated cytolysis remains unknown. Recently, a peptidyl-prolyl isomerase located within the mitochondrial matrix, cyclophilin D (PPIF), was shown to regulate necrotic, but not apoptotic, cell death in vitro in fibroblasts, hepatocytes, and cardiomyocytes. Whether cyclophilin D regulates necrosis in hematopoietic cells such as eosinophils remains unknown. We used PPIF-deficient (Ppif(-/-)) mice to test whether cyclophilin D is required for regulating eosinophil necrosis. PPIF deficiency did not affect eosinophil development or maturation at baseline. After in vitro ionomycin or H2O2 treatment, Ppif(-/-) eosinophils were significantly protected from Ca(2+) overload- or oxidative stress-induced necrosis. Additionally, Ppif(-/-) eosinophils demonstrated significantly decreased necrosis, but not apoptosis, in response to Siglec-F cross-linking, a stimulus associated with eosinophil-mediated processes in vitro and in vivo. When treated with apoptosis inducers, Ppif(+/+) and Ppif(-/-) eosinophils exhibited no significant difference in apoptosis or secondary necrosis. Finally, in a dextran sodium sulfate-induced colitis model, although levels of colitogenic cytokines and eosinophil-selective chemokines were comparable between Ppif(+/+) and Ppif(-/-) mice, the latter exhibited decreased clinical outcomes. This correlated with significantly reduced eosinophil cytolysis in the colon. Collectively, our present studies demonstrate that murine eosinophil necrosis is regulated in vitro and in vivo by cyclophilin D, at least in part, thus providing new insight into the mechanism of eosinophil necrosis and release of free extracellular granules in eosinophil-associated diseases. PMID:26893161

  7. Regulation of apoptosis and cell cycle in irradiated mouse brain

    Energy Technology Data Exchange (ETDEWEB)

    Oh, Won Yong; Song, Mi Hee; Hung, Eun Ji; Seong, Jin Sil; Suh, Chang Ok [College of Medicine, Yonsei Univ., Seoul (Korea, Republic of)

    2001-06-01

    To investigate the regulation of apoptosis and cell cycle in mouse brain irradiation. 8-week old male mice, C57B 1/6J were given whole body {gamma} -radiation with a single dose of 25 Gy using Cobalt 60 irradiator. At different times 1, 2, 4, 8 and 24hr after irradiation, mice were killed and brain tissues were collected. Apoptotic cells were scored by TUNEL assay. Expression of p53, Bcl-2, and Bax and cell cycle regulating molecules; cyclins BI, D1, E and cdk2, cdk4, p34{sup cdc2} were analysed by Western blotting. Cell cycle was analysed by flow cytometry. The peak of radiation induced apoptosis is shown at 8 hour after radiation. With a single 25 Gy irradiation, the peak of apoptotic index in C57B1/6J is 24.0{+-}0.25 (p<0.05) at 8 hour after radiation. Radiation upregulated the expression of p53/tubulin, Bax/tubulin, and Bcl-2/tubulin with 1.3, 1.1 and 1.45 fold increase, respectively were shown at the peak level at 8 hour after radiation. The levels of cell cycle regulating molecules after radiation are not changed significantly except cyclin D1 with 1.3 fold increase. Fractions of Go-G 1, G2-M and S phase in the cell cycle does not specific changes by time. In mouse brain tissue, radiation induced apoptosis is particularly shown in a specific area, subependyma. These results and lack of radiation induced changes in cell cycle offer better understanding of radiation response of normal brain tissue.

  8. Regulative Function of Telomerase and Extracelluar Regulated Protein Kinases to Leukemic Cell Apoptosis

    Institute of Scientific and Technical Information of China (English)

    李登举; 张瑶珍; 曹文静; 孙岚; 徐慧珍; 路武

    2002-01-01

    Summary: In order to investigate the regulative function of telomerase and phosphorylated (acti-vated) extracelluar regulated protein kinase (ERK) i and 2 in the leukemic cell lines HL-60 andK562 proliferation inhibition and apoptosis, three chemotherapeutic drugs Harringtonine (HRT),Vincristine(VCR)and Etoposide(Vp16)were selected as inducers. The proliferation inhibition ratewas detected by MTT method, the cell cycle and cell apoptosis was analyzed by flow cytometryand the telomerase activity was detected by the telomeric repeat amplification protocol (TRAP)assay and bioluminescence analysis method. The phosphorylated ERK1/2 protein expression wasdetected by western blot method. The results showed that HRT, VCR and Vp16 could inhibit cellproliferation, induce apoptosis, inhibit telomerase activity and down-regulate the protein expres-sion of phosphorylated ERK. It was suggested that ERK signal transduction pathway was involvedin the down-regulation of telomerase activity and the onset of apoptosis in the leukemic cells treat-ed by HRT, VCR and Vp16.

  9. p53 selectively regulates developmental apoptosis of rod photoreceptors.

    Directory of Open Access Journals (Sweden)

    Linda Vuong

    Full Text Available Retinal cells become post-mitotic early during post-natal development. It is likely that p53, a well-known cell cycle regulator, is involved in regulating the genesis, differentiation and death of retinal cells. Furthermore, retinal cells are under constant oxidative stress that can result in DNA damage, due to the extremely high level of metabolic activity associated with phototransduction. If not repaired, this damage may result in p53-dependent cell death and ensuing vision loss. In this study, the role of p53 during retinal development and in the post-mitotic retina is investigated. A previously described super p53 transgenic mouse that expresses an extra copy of the mouse p53 gene driven by its endogenous promoter is utilized. Another transgenic mouse (HIP that expresses the p53 gene in rod and cone photoreceptors driven by the human interphotoreceptor retinoid binding protein promoter was generated. The electroretinogram (ERG of the super p53 mouse exhibited reduced rod-driven scotopic a and b wave and cone-driven photopic b wave responses. This deficit resulted from a reduced number of rod photoreceptors and inner nuclear layer cells. However, the reduced photopic signal arose only from lost inner retinal neurons, as cone numbers did not change. Furthermore, cell loss was non-progressive and resulted from increased apoptosis during retinal developmental as determined by TUNEL staining. In contrast, the continuous and specific expression of p53 in rod and cone photoreceptors in the mature retinas of HIP mice led to the selective loss of both rods and cones. These findings strongly support a role for p53 in regulating developmental apoptosis in the retina and suggest a potential role, either direct or indirect, for p53 in the degenerative photoreceptor loss associated with human blinding disorders.

  10. Regulation of apoptosis by the papillomavirus E6 oncogene

    Institute of Scientific and Technical Information of China (English)

    Ting-Ting Li; Li-Na Zhao; Zhi-Guo Liu; Ying Han; Dai-Ming Fan

    2005-01-01

    Infection with human papillomaviruses is strongly associated with the development of multiple cancers including esophageal squamous cell carcinoma. The HPV E6 gene is essential for the oncogenic potential of HPV.The recgulation of apoptosis by oncogene has been relatel to carcinogenesis closely; therefore, the modulation of E6 on cellular apoptosis has become a hot research topic recently. Inactivation of the pro-apoptotic tumor suppressor p53 by E6 is an important mechanism by which E6promotes cell growth; it is expected that inactivation of p53 by E6 should lead to a reduction in cellular apoptosis,numerous studies showed that E6 could in fact sensitize cells to apoptosis. The molecular basis for apoptosis modulation by E6 is poorly understood. In this article, we will present an overview of observations and current understanding of molecular basis for E6-induced apoptosis.

  11. Dimerization of two novel apoptosis-inducing proteins and its function in regulating cell apoptosis

    Institute of Scientific and Technical Information of China (English)

    刘青珍; 甘淼; 齐义鹏; 李凌云; 齐兵

    2003-01-01

    Asy (apoptosis/saibousi Yutsudo) is a novel apoptosis-inducing gene found in 1999 by Yutsudo group in Japan. In 2000, Qi Bing et al. cloned another novel gene, named hap (homologue of ASY protein), which encoded the ASY interact ing protein, from human lung cell line (WI-38) cDNA library by using yeast two-h ybrid system. It has been proved that ASY formed homodimer in yeast and human ce ll line, ASY and HAP formed heterodimer in yeast cells, and both induced cell ap optosis in human tumor cell lines Sao2 and CGL4. This paper showed that HAP coul d form homodimer in yeast cells by yeast two-hybrid system; HAP and ASY could pr oduce heterodimer in human cell line by cross-immunoprecipitation test; by using apoptosis-testing technologies such as AnnexinV, TUNEL, DNA ladder and Flow Cyt ometry, the cell apoptosis in human normal or tumor cell lines transfected with hap or asy individually or cotransfected by the both was qualified or quantified . It was firstly demonstrated that ASY or HAP induced cell apoptosis not only in human tumor cell lines, but also in human normal cell lines. Moreover, we prove d that the heterodimer between ASY and HAP decreased apoptosis-inducing activity from the homodimer of ASY or HAP. It revealed that by choosing to form heterodi mer or homodimer between ASY and / or HAP is an important mechanism of regulatin g apoptosis in human cell lines.

  12. Soluble tyrosinase is an endoplasmic reticulum (ER)-associated degradation substrate retained in the ER by calreticulin and BiP/GRP78 and not calnexin.

    Science.gov (United States)

    Popescu, Costin I; Paduraru, Crina; Dwek, Raymond A; Petrescu, Stefana M

    2005-04-01

    Tyrosinase is a type I membrane protein regulating the pigmentation process in humans. Mutations of the human tyrosinase gene cause the tyrosinase negative type I oculocutaneous albinism (OCAI). Some OCAI mutations were shown to delete the transmembrane domain or to affect its hydrophobic properties, resulting in soluble tyrosinase mutants that are retained in the endoplasmic reticulum (ER). To understand the specific mechanisms involved in the ER retention of soluble tyrosinase, we have constructed a tyrosinase mutant truncated at its C-terminal end and investigated its maturation process. The mutant is retained in the ER, and it is degraded through the proteasomal pathway. We determined that the mannose trimming is required for an efficient degradation process. Moreover, this soluble ER-associated degradation substrate is stopped at the ER quality control checkpoint with no requirements for an ER-Golgi recycling pathway. Co-immmunoprecipitation experiments showed that soluble tyrosinase interacts with calreticulin and BiP/GRP78 (and not calnexin) during its ER transit. Expression of soluble tyrosinase in calreticulin-deficient cells resulted in the export of soluble tyrosinase of the ER, indicating the calreticulin role in ER retention. Taken together, these data show that OCAI soluble tyrosinase is an ER-associated degradation substrate that, unlike other albino tyrosinases, associates with calreticulin and BiP/GRP78. The lack of specificity for calnexin interaction reveals a novel role for calreticulin in OCAI albinism.

  13. Soluble tyrosinase is an endoplasmic reticulum (ER)-associated degradation substrate retained in the ER by calreticulin and BiP/GRP78 and not calnexin.

    Science.gov (United States)

    Popescu, Costin I; Paduraru, Crina; Dwek, Raymond A; Petrescu, Stefana M

    2005-04-01

    Tyrosinase is a type I membrane protein regulating the pigmentation process in humans. Mutations of the human tyrosinase gene cause the tyrosinase negative type I oculocutaneous albinism (OCAI). Some OCAI mutations were shown to delete the transmembrane domain or to affect its hydrophobic properties, resulting in soluble tyrosinase mutants that are retained in the endoplasmic reticulum (ER). To understand the specific mechanisms involved in the ER retention of soluble tyrosinase, we have constructed a tyrosinase mutant truncated at its C-terminal end and investigated its maturation process. The mutant is retained in the ER, and it is degraded through the proteasomal pathway. We determined that the mannose trimming is required for an efficient degradation process. Moreover, this soluble ER-associated degradation substrate is stopped at the ER quality control checkpoint with no requirements for an ER-Golgi recycling pathway. Co-immmunoprecipitation experiments showed that soluble tyrosinase interacts with calreticulin and BiP/GRP78 (and not calnexin) during its ER transit. Expression of soluble tyrosinase in calreticulin-deficient cells resulted in the export of soluble tyrosinase of the ER, indicating the calreticulin role in ER retention. Taken together, these data show that OCAI soluble tyrosinase is an ER-associated degradation substrate that, unlike other albino tyrosinases, associates with calreticulin and BiP/GRP78. The lack of specificity for calnexin interaction reveals a novel role for calreticulin in OCAI albinism. PMID:15677452

  14. Transient calnexin interaction confers long-term stability on folded K+ channel protein in the ER.

    Science.gov (United States)

    Khanna, Rajesh; Lee, Eun Jeon; Papazian, Diane M

    2004-06-15

    We recently showed that an unglycosylated form of the Shaker potassium channel protein is retained in the endoplasmic reticulum (ER) and degraded by proteasomes in mammalian cells despite apparently normal folding and assembly. These results suggest that channel proteins with a native structure can be substrates for ER-associated degradation. We have now tested this hypothesis using the wild-type Shaker protein. Wild-type Shaker is degraded by cytoplasmic proteasomes when it is trapped in the ER and prevented from interacting with calnexin. Neither condition alone is sufficient to destabilize the protein. Proteasomal degradation of the wild-type protein is abolished when ER mannosidase I trimming of the core glycan is inhibited. Our results indicate that transient interaction with calnexin provides long-term protection from ER-associated degradation. PMID:15161937

  15. X-linked inhibitor of apoptosis regulates T cell effector function

    DEFF Research Database (Denmark)

    Zehntner, Simone P; Bourbonnière, Lyne; Moore, Craig S;

    2007-01-01

    To understand how the balance between pro- and anti-apoptotic signals influences effector function in the immune system, we studied the X-linked inhibitor of apoptosis (XIAP), an endogenous regulator of cellular apoptosis. Real-time PCR showed increased XIAP expression in blood of mice...... and oligodendrocytes were not affected; neither did apoptosis increase in liver, where XIAP knockdown also occurred. ASO-XIAP increased susceptibility of T cells to activation-induced apoptosis in vitro. Our results identify XIAP as a critical controller of apoptotic susceptibility of effector T cell function...

  16. Stochastic modeling of p53-regulated apoptosis upon radiation damage

    CERN Document Server

    Bhatt, Divesh; Bahar, Ivet

    2011-01-01

    We develop and study the evolution of a model of radiation induced apoptosis in cells using stochastic simulations, and identified key protein targets for effective mitigation of radiation damage. We identified several key proteins associated with cellular apoptosis using an extensive literature survey. In particular, we focus on the p53 transcription dependent and p53 transcription independent pathways for mitochondrial apoptosis. Our model reproduces known p53 oscillations following radiation damage. The key, experimentally testable hypotheses that we generate are - inhibition of PUMA is an effective strategy for mitigation of radiation damage if the treatment is administered immediately, at later stages following radiation damage, inhibition of tBid is more effective.

  17. Peptides Regulate Cortical Thymocytes Differentiation, Proliferation, and Apoptosis

    Directory of Open Access Journals (Sweden)

    V. Kh. Khavinson

    2011-01-01

    Full Text Available The processes of differentiation, proliferation, and apoptosis were studied in a cell culture of human cortical thymocytes under the influence of short peptides T-32 (Glu-Asp-Ala and T-38 (Lys-Glu-Asp. Peptides T-32 and T-38 amplified cortical thymocytes differentiation towards regulatory T cells, increased their proliferative activity, and decreased the level of apoptosis. Moreover, peptides under study stimulated proliferative and antiapoptotic activity of the mature regulatory T cells.

  18. Molecular Mechanisms Regulating Ocular Apoptosis in Zebrafish gdf6a Mutants

    DEFF Research Database (Denmark)

    Pant, Sameer D.; March, Lindsey D.; Famulski, Jakub K.;

    2013-01-01

    PURPOSE. To characterize the molecular mechanisms underlying retinal apoptosis induced by loss of Gdf6, a TGF beta ligand. METHODS. The role of Gdf6 in regulating apoptosis was studied using a zebrafish gdf6a(-/-) mutant, which encodes a truncated, nonfunctional protein. To investigate whether...... intrinsic or extrinsic apoptotic mechanisms were involved, morpholino antisense oligonucleotides targeting baxa, baxb, and p53 were employed. Caspase-3 immunohistochemistry (IHC) was performed to assay apoptosis. Pharmacologic inhibition (using SB203580) and IHC were used to investigate the role of p38...... mitogen activated protein (MAP) kinase activation in gdf6a(-/-) induced apoptosis. To assess the role of Gdf6a in transcriptional regulation of TGF beta signal transducers, in situ hybridization (ISH) was performed using probes to smad1, 5, 7, and 8. RESULTS. Results indicate maximal ocular apoptosis...

  19. DMPD: Regulation of nitric oxide synthesis and apoptosis by arginase and argininerecycling. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 17513437 Regulation of nitric oxide synthesis and apoptosis by arginase and arginine...on of nitric oxide synthesis and apoptosis by arginase and argininerecycling. PubmedID 17513437 Title Regula...tion of nitric oxide synthesis and apoptosis by arginase and argininerecycling. A

  20. The regulation of apoptosis in kidney development: implications for nephron number and pattern?

    Directory of Open Access Journals (Sweden)

    Jacqueline eHo

    2014-11-01

    Full Text Available Apoptosis is essential to remodel developing structures and eliminate superfluous cells in a controlled manner during normal development, and continues to be an important component of tissue remodeling and regeneration during an organism’s lifespan, or as a response to injury. This mini-review will discuss recent studies that have provided insights into the roles of apoptosis in the determination of nephron number and pattern, during normal and abnormal kidney development. The regulation of congenital nephron endowment has implications for risk of chronic kidney disease in later life, whereas abnormalities in nephron pattern are associated with congenital anomalies of the kidney and urinary tract (the leading cause of renal disease in children. Tight regulation of apoptosis is required in normal renal morphogenesis, although many questions remain regarding the regulation of apoptosis by genetic, epigenetic and environmental factors, in addition to the functional requirement of different components of the apoptotic pathway.

  1. Methylprednisolone exerts neuroprotective effects by regulating autophagy and apoptosis

    Institute of Scientific and Technical Information of China (English)

    Wei Gao; Shu-rui Chen; Meng-yao Wu; Kai Gao; Yuan-long Li; Hong-yu Wang; Chen-yuan Li; Hong Li

    2016-01-01

    Methylprednisolone markedly reduces autophagy and apoptosis after secondary spinal cord injury. Here, we investigated whether pretreat-ment of cells with methylprednisolone would protect neuron-like cells from subsequent oxidative damagevia suppression of autophagy and apoptosis. Cultured N2a cells were pretreated with 10 µM methylprednisolone for 30 minutes, then exposed to 100 µM H2O2 for 24 hours. Inverted phase contrast microscope images, MTT assay, lfow cytometry and western blot results showed that, compared to cells ex-posed to 100 µM H2O2 alone, cells pretreated with methylprednisolone had a signiifcantly lower percentage of apoptotic cells, maintained a healthy morphology, and showed downregulation of autophagic protein light chain 3B and Beclin-1 protein expression. These ifndings indicate that methylprednisolone exerted neuroprotective effects against oxidative damage by suppressing autophagy and apoptosis.

  2. Smac/DIABLO regulates the apoptosis of hypertrophic scar fibroblasts.

    Science.gov (United States)

    Liu, Bao-Heng; Chen, Liang; Li, Shi-Rong; Wang, Zhen-Xiang; Cheng, Wen-Guang

    2013-09-01

    In abnormal skin wound healing, hypertrophic scars (HS) are characterized by excessive fibroblast hypercellularity and an overproduction of collagen, leading to atypical extracellular matrix (ECM) remodeling. Although the exact mechanisms of HS remain unclear, decreased HS fibroblast (HSFB) apoptosis and increased proliferation are evident in the development of HS. In this study, the contribution of the second mitochondria-derived activator of caspases/direct inhibitor of apoptosis protein (IAP)-binding protein with a low isoelectric point (pI) (Smac/DIABLO), an apoptosis-promoting protein released from the mitochondria, was investigated in human normal skin and HSFB cultures. The expression of Smac/DIABLO is usually decreased in many malignant tumors compared with normal tissues. Immunohistochemical analysis of skin tissues and the western blot analyses of fibroblasts revealed that the expression of Smac/DIABLO was lower in HS tissues compared with normal skin tissues. Of note, adenovirus-mediated Smac/DIABLO overexpression in the cultured HSFBs significantly reduced cell proliferation, as detected by the cell counting kit-8, and increased caspase-3 and -9 activity, as detected by spectrofluorimetry. In addition, it increased apoptosis, as detected by fluorescence-activated cell sorting (FACS). Furthermore, we found that the silencing of Smac with siRNA in the HSFBs induced a noticeable decrease in caspase-3 and -9 activity, leading to a significant reduction in apoptosis. In addition, the mRNA expression of type I and III pro-collagen detected in the HSFBs was significantly increased following the silencing of Smac with siRNA and was inhibited following Smac/DIABLO overexpression, as shown by real-time RT-PCR. In conclusion, Smac/DIABLO decreases the proliferation and increases the apoptosis of HSFBs. To our knowledge, the data from our study suggest for the first time that Smac/DIABLO is a novel therapeutic target for HS.

  3. Nitric oxide modulates hypoxic pulmonary smooth muscle cell proliferation and apoptosis by regulating carbon monoxide pathway

    Institute of Scientific and Technical Information of China (English)

    Yan-fei WANG; Hong TIAN; Chao-shu TANG; Hong-fang JIN; Jun-bao DU

    2007-01-01

    Aim: To explore the role of carbon monoxide (CO) in the regulation of hypoxic pulmonary artery smooth muscle cell (PASMC) proliferation and apoptosis by nitric oxide (NO). Methods: PASMC of Wistar rats was cultured in vitro in the presence of a NO donor, sodium nitroprusside, or an inhibitor of heme oxygenase (HO), zinc protoporphyrin-IX, or under both normoxic and hypoxic conditions.Nitrite and carboxyhemoglobin in PASMC medium were detected with spectrophotometry. The proliferating and apoptotic percentage of PASMC was measured by flow cytometry. The expression of HO-1 mRNA in PASMC was analyzed by fluorescent real-time quantitative PCR, and the proliferating cell nuclear antigen and caspase-3 were examined by immunocytochemical analysis. Results: The results showed that hypoxia suppressed NO generation from PASMC, which promoted hypoxic PASMC proliferation and induced apoptosis. Meanwhile, hy-poxia induced HO-1 expression in PASMC and promoted CO production from PASMC, which inhibited PASMC proliferation and regulated PASMC apoptosis. NO upregulated the expression of HO-1 mRNA in hypoxic PASMC; NO also inhib-ited proliferation and promoted apoptosis of hypoxic PASMC, possibly by regu-lating the production of CO. Conclusion: The results indicated that CO could inhibit proliferation and regulate apoptosis of PASMC, and NO inhibited prolifera-tion and promoted apoptosis of hypoxic PASMC, possibly by regulating the pro-duction of CO.

  4. Tissue Specific Roles of Dynein Light Chain 1 in Regulating Germ Cell Apoptosis in Ceanorhabditis elegans

    DEFF Research Database (Denmark)

    Morthorst, Tine Hørning

    2015-01-01

    Apoptosis is the process in which external or internal cues activate certain killing pathways in a cell to induce self-elimination. Apoptosis is a conserved key process required to modulate embryogenesis and for removal of damaged or superfluous cells. Dysregulation of apoptosis is implicated...... in the etiology of many diseases, including cancer, neurodegenerative, cardiovascular and autoimmune diseases. Several of the first genes found to regulate apoptosis were discovered in the nematode Caenorhabditis elegans. In this project, two different and tissue specific roles of C. elegans dynein light chain 1...... (dlc-1) in apoptosis are described. DLC-1 is a part of the motor complex dynein, which moves along microtubules inside the cell. DLC-1 has been demonstrated to have both dynein dependent and independent functions in mammalian cells, which is also apparent from the studies presented here. Specifically...

  5. MyoD regulates apoptosis of myoblasts through microRNA-mediated down-regulation of Pax3

    OpenAIRE

    Hirai, Hiroyuki; Verma, Mayank; Watanabe, Shuichi; Tastad, Christopher; Asakura, Yoko; Asakura, Atsushi

    2010-01-01

    The molecules that regulate the apoptosis cascade are also involved in differentiation and syncytial fusion in skeletal muscle. MyoD is a myogenic transcription factor that plays essential roles in muscle differentiation. We noticed that MyoD−/− myoblasts display remarkable resistance to apoptosis by down-regulation of miR-1 (microRNA-1) and miR-206 and by up-regulation of Pax3. This resulted in transcriptional activation of antiapoptotic factors Bcl-2 and Bcl-xL. Forced MyoD expression induc...

  6. Noxa/Mcl-1 Balance Regulates Susceptibility of Cells to Camptothecin-Induced Apoptosis

    Directory of Open Access Journals (Sweden)

    Yide Mei

    2007-10-01

    Full Text Available Although camptothecin (CPT has been reported to induce apoptosis in various cancer cells, the molecular details of this regulation remain largely unknown. In this study, we demonstrate that 131-113-only protein Noxa is upregulated during CPT-induced apoptosis, which is independent of p53. In addition, we show that phosphatidylinositol 3-kinase (PI3K/Akt signaling pathway is responsible for Noxa's induction. Luciferase assay, cAMP response element binding protein (CREB knockdown experiments further demonstrate that CREB is involved in the transcriptional upregulation of Noxa. Moreover, blocking Noxa expression using specific small interfering ribonucleic acid (siRNA significantly reduces the apoptosis in response to CPT, indicating that Noxa is an essential mediator for CPT-induced apoptosis. Interestingly, antiapoptotic Mcl-1 was also upregulated through PI3K/Akt signaling pathway upon CPT treatment. Using immunoprecipitation assay, Noxa was found to interact with Mcl-1 in the presence or absence of CPT. Knockdown of Mcl-1 expression by short hairpin ribonucleic acid (shRNA was shown to potentiate CPT-induced apoptosis. Consistently, ectopic overexpression of Mcl-1 rescued cells from apoptosis induced by CPT. Cells coexpressing Noxa, Mcl-1 at different ratio correlates well with the extent of apoptosis, suggesting that the balance between Noxa, Mcl-1 may determine the susceptibility of HeLa cells to CPT-induced apoptosis.

  7. Kaposi's Sarcoma Herpesvirus microRNAs Target Caspase 3 and Regulate Apoptosis

    OpenAIRE

    Guillaume Suffert; Georg Malterer; Jean Hausser; Johanna Viiliäinen; Aurélie Fender; Maud Contrant; Tomi Ivacevic; Vladimir Benes; Frédéric Gros; Olivier Voinnet; Mihaela Zavolan; Ojala, Päivi M.; Haas, Juergen G.; Sébastien Pfeffer

    2011-01-01

    Kaposi's sarcoma herpesvirus (KSHV) encodes a cluster of twelve micro (mi)RNAs, which are abundantly expressed during both latent and lytic infection. Previous studies reported that KSHV is able to inhibit apoptosis during latent infection; we thus tested the involvement of viral miRNAs in this process. We found that both HEK293 epithelial cells and DG75 cells stably expressing KSHV miRNAs were protected from apoptosis. Potential cellular targets that were significantly down-regulated upon KS...

  8. Regulation of UV induced apoptosis in human melanocytes

    OpenAIRE

    Bivik, Cecilia

    2007-01-01

    Malignant melanoma arises from the pigment producing melanocytes in epidermis and is the most aggressive type of skin cancer. The incidence of malignant melanoma is increasing faster than any other type of cancer in white population worldwide, with a doubling rate every 10-20 years. So far, the only identified external risk factor for malignant melanoma is UV exposure. Elimination of photodamaged cells by apoptosis (programmed cell death) is essential to prevent tumor formation. Melanocytes a...

  9. VMP1 related autophagy and apoptosis in colorectal cancer cells: VMP1 regulates cell death

    Energy Technology Data Exchange (ETDEWEB)

    Qian, Qinyi [Department of Ultrasonograph, Changshu No. 2 People’s Hospital, Changshu (China); Zhou, Hao; Chen, Yan [Department of General Surgery, The First Affiliated Hospital of Soochow University, Suzhou (China); Shen, Chenglong [Department of General Surgery, Changshu No. 2 People’s Hospital, Changshu (China); He, Songbing; Zhao, Hua; Wang, Liang [Department of General Surgery, The First Affiliated Hospital of Soochow University, Suzhou (China); Wan, Daiwei, E-mail: 372710369@qq.com [Department of Hepatobiliary Surgery, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou (China); Gu, Wen, E-mail: 505339704@qq.com [Department of General Surgery, The First Affiliated Hospital of Soochow University, Suzhou (China)

    2014-01-17

    Highlights: •This research confirmed VMP1 as a regulator of autophagy in colorectal cancer cell lines. •We proved the pro-survival role of VMP1-mediated autophagy in colorectal cancer cell lines. •We found the interaction between VMP1 and BECLIN1 also existing in colorectal cancer cell lines. -- Abstract: Vacuole membrane protein 1 (VMP1) is an autophagy-related protein and identified as a key regulator of autophagy in recent years. In pancreatic cell lines, VMP1-dependent autophagy has been linked to positive regulation of apoptosis. However, there are no published reports on the role of VMP1 in autophagy and apoptosis in colorectal cancers. Therefore, to address this gap of knowledge, we decided to interrogate regulation of autophagy and apoptosis by VMP1. We have studied the induction of autophagy by starvation and rapamycin treatment in colorectal cell lines using electron microscopy, immunofluorescence, and immunoblotting. We found that starvation-induced autophagy correlated with an increase in VMP1 expression, that VMP1 interacted with BECLIN1, and that siRNA mediated down-regulation of VMP1-reduced autophagy. Next, we examined the relationship between VMP1-dependent autophagy and apoptosis and found that VMP1 down-regulation sensitizes cells to apoptosis and that agents that induce apoptosis down-regulate VMP1. In conclusion, similar to its reported role in other cell types, VMP1 is an important regulator of autophagy in colorectal cell lines. However, in contrast to its role in pancreatic cell lines, in colorectal cancer cells, VMP1-dependent autophagy appears to be pro-survival rather than pro-cell death.

  10. The vitronectin RGD motif regulates TGF-β-induced alveolar epithelial cell apoptosis.

    Science.gov (United States)

    Wheaton, Amanda K; Velikoff, Miranda; Agarwal, Manisha; Loo, Tiffany T; Horowitz, Jeffrey C; Sisson, Thomas H; Kim, Kevin K

    2016-06-01

    Transforming growth factor-β (TGF-β) is a critical driver of acute lung injury and fibrosis. Injury leads to activation of TGF-β, which regulates changes in the cellular and matrix makeup of the lung during the repair and fibrosis phase. TGF-β can also initiate alveolar epithelial cell (AEC) apoptosis. Injury leads to destruction of the laminin-rich basement membrane, which is replaced by a provisional matrix composed of arginine-glycine-aspartate (RGD) motif-containing plasma matrix proteins, including vitronectin and fibronectin. To determine the role of specific matrix proteins on TGF-β-induced apoptosis, we studied primary AECs cultured on different matrix conditions and utilized mice with deletion of vitronectin (Vtn(-/-)) or mice in which the vitronectin RGD motif is mutated to nonintegrin-binding arginine-glycine-glutamate (RGE) (Vtn(RGE/RGE)). We found that AECs cultured on fibronectin and vitronectin or in wild-type mouse serum are resistant to TGF-β-induced apoptosis. In contrast, AECs cultured on laminin or in serum from Vtn(-/-) or Vtn(RGE/RGE) mice undergo robust TGF-β-induced apoptosis. Plasminogen activator inhibitor-1 (PAI-1) sensitizes AECs to greater apoptosis by disrupting AEC engagement to vitronectin. Inhibition of integrin-associated signaling proteins augments AEC apoptosis. Mice with transgenic deletion of PAI-1 have less apoptosis after bleomycin, but deletion of vitronectin or disruption of the vitronectin RGD motif reverses this protection, suggesting that the proapoptotic function of PAI-1 is mediated through vitronectin inhibition. Collectively, these data suggest that integrin-matrix signaling is an important regulator of TGF-β-mediated AEC apoptosis and that PAI-1 functions as a natural regulator of this interaction. PMID:27106291

  11. Voltage dependent anion channel-1 regulates death receptor mediated apoptosis by enabling cleavage of caspase-8

    International Nuclear Information System (INIS)

    Activation of the extrinsic apoptosis pathway by tumour necrosis factor related apoptosis inducing ligand (TRAIL) is a novel therapeutic strategy for treating cancer that is currently under clinical evaluation. Identification of molecular biomarkers of resistance is likely to play an important role in predicting clinical anti tumour activity. The involvement of the mitochondrial type 1 voltage dependent anion channel (VDAC1) in regulating apoptosis has been highly debated. To date, a functional role in regulating the extrinsic apoptosis pathway has not been formally excluded. We carried out stable and transient RNAi knockdowns of VDAC1 in non-small cell lung cancer cells, and stimulated the extrinsic apoptotic pathway principally by incubating cells with the death ligand TRAIL. We used in-vitro apoptotic and cell viability assays, as well as western blot for markers of apoptosis, to demonstrate that TRAIL-induced toxicity is VDAC1 dependant. Confocal microscopy and mitochondrial fractionation were used to determine the importance of mitochondria for caspase-8 activation. Here we show that either stable or transient knockdown of VDAC1 is sufficient to antagonize TRAIL mediated apoptosis in non-small cell lung cancer (NSCLC) cells. Specifically, VDAC1 is required for processing of procaspase-8 to its fully active p18 form at the mitochondria. Loss of VDAC1 does not alter mitochondrial sensitivity to exogenous caspase-8-cleaved BID induced mitochondrial depolarization, even though VDAC1 expression is essential for TRAIL dependent activation of the intrinsic apoptosis pathway. Furthermore, expression of exogenous VDAC1 restores the apoptotic response to TRAIL in cells in which endogenous VDAC1 has been selectively silenced. Expression of VDAC1 is required for full processing and activation of caspase-8 and supports a role for mitochondria in regulating apoptosis signaling via the death receptor pathway

  12. Oxytocin ameliorates the immediate myocardial injury in heart transplant through down regulation of the neutrophil dependent myocardial apoptosis

    Directory of Open Access Journals (Sweden)

    F Fadhil Al-Amran

    2014-01-01

    Conclusion: Oxytocin ameliorates myocardial injury in heart transplant through down-regulation the myocardial inflammatory response, reactive oxygen species, and neutrophil-dependant myocardial apoptosis.

  13. Independent regulation of reovirus membrane penetration and apoptosis by the mu1 phi domain.

    Directory of Open Access Journals (Sweden)

    Pranav Danthi

    2008-12-01

    Full Text Available Apoptosis plays an important role in the pathogenesis of reovirus encephalitis. Reovirus outer-capsid protein mu1, which functions to penetrate host cell membranes during viral entry, is the primary regulator of apoptosis following reovirus infection. Ectopic expression of full-length and truncated forms of mu1 indicates that the mu1 phi domain is sufficient to elicit a cell death response. To evaluate the contribution of the mu1 phi domain to the induction of apoptosis following reovirus infection, phi mutant viruses were generated by reverse genetics and analyzed for the capacity to penetrate cell membranes and elicit apoptosis. We found that mutations in phi diminish reovirus membrane penetration efficiency by preventing conformational changes that lead to generation of key reovirus entry intermediates. Independent of effects on membrane penetration, amino acid substitutions in phi affect the apoptotic potential of reovirus, suggesting that phi initiates apoptosis subsequent to cytosolic delivery. In comparison to wild-type virus, apoptosis-defective phi mutant viruses display diminished neurovirulence following intracranial inoculation of newborn mice. These results indicate that the phi domain of mu1 plays an important regulatory role in reovirus-induced apoptosis and disease.

  14. Swelling-activated ion channels: functional regulation in cell-swelling, proliferation and apoptosis

    DEFF Research Database (Denmark)

    Stutzin, A; Hoffmann, E K

    2006-01-01

    Cell volume regulation is one of the most fundamental homeostatic mechanisms and essential for normal cellular function. At the same time, however, many physiological mechanisms are associated with regulatory changes in cell size meaning that the set point for cell volume regulation is under phys...... as key players in the maintenance of normal steady-state cell volume, with particular emphasis on the intracellular signalling pathways responsible for their regulation during hypotonic stress, cell proliferation and apoptosis....

  15. Modulator of Apoptosis 1: A Highly Regulated RASSF1A-Interacting BH3-Like Protein

    Directory of Open Access Journals (Sweden)

    Jennifer Law

    2012-01-01

    Full Text Available Modulator of apoptosis 1 (MOAP-1 is a BH3-like protein that plays key roles in both the intrinsic and extrinsic modes of cell death or apoptosis. MOAP-1 is part of the Ras association domain family 1A (RASSF1A/MOAP-1 pro-apoptotic extrinsic signaling pathway that regulates apoptosis by utilizing death receptors such as tumor necrosis factor α (TNFα or TNF-related apoptosis-inducing ligand (TRAIL to inhibit abnormal growth. RASSF1A is a bona fide tumor suppressor gene that is epigenetically silenced by promoter-specific methylation in numerous human cancers. MOAP-1 is a downstream effector of RASSF1A that promotes Bax activation and cell death and is highly regulated during apoptosis. We speculate that MOAP-1 and RASSF1A are important elements of an “apoptotic checkpoint” that directly influences the outcome of cell death. The failure to regulate this pro-apoptotic pathway may result in the appearance of cancer and possibly other disorders. Although loss of RASSF1A expression is frequently observed in human cancers, it is currently unknown if MOAP-1 expression may also be affected during carcinogenesis to result in uncontrolled malignant growth. In this article, we will summarize what is known about the biological role(s of MOAP-1 and how it functions as a downstream effector to RASSF1A.

  16. Altered cell cycle regulation helps stem-like carcinoma cells resist apoptosis

    OpenAIRE

    Dalton Stephen; Chappell James

    2010-01-01

    Abstract Reemergence of carcinomas following chemotherapy and/or radiotherapy is not well understood, but a recent study in BMC Cancer suggests that resistance to apoptosis resulting from altered cell cycle regulation is crucial. See research article: http://biomedcentral.com/1471-2407/10/166

  17. Mechanisms of acupuncture and moxibustion in regulation of epithelial cell apoptosis in rat ulcerative colitis

    Institute of Scientific and Technical Information of China (English)

    Huan-Gan Wu; Xiao Gong; Li-Qing Yao; Wei Zhang; Yin Shi; Hui-Rong Liu; Ye-Jing Gong; Li-Bin Zhou; Yi Zhu

    2004-01-01

    AIM: To investigate the effect of acupuncture and moxibustion on epithelial cell apoptosis and expression of Bcl-2, Bax, fas and FasL proteins in rat ulcerative colitis.METHODS: A rat model of ulcerative colitis was estabelished by immunological methods and local stimulation. All rats were randomly divided into model control group (MC),electro-acupuncture group (EA), herbs-partition moxibustion group (HPM). Normal rats were used as normal control group (NC). Epithelial cell apoptosis and expression of Bcl-2, Bax, fas and FasL proteins were detected by TUNEL and immunohistochemiscal method respectively.RESULTS: The number of epithelial cell apoptosis in MC was significantly higher than that in NC, and was markedly decreased after the treatment with herbs-partition moxibustion or electro-acupuncture. The expression of Bcl2, Bax, fas and FasL in colonic epithelial cells in MC was higher than that in NC, and was markedly down- regulated by herbspartition moxibustion or electro-acupuncture treatment.CONCLUSION: The pathogenesis of ulcerative colitis in rats involves abnormality of apoptosis. Acupuncture and moxibustion can regulate the expression of Bcl-2, Bax, fas and FasL proteins and inhibit the apoptosis of epithelial cells of ulcerative colitis in rats by Bcl-2/Bax, fas/FasL pathways.

  18. Impact of the lectin chaperone calnexin on the stress response, virulence and proteolytic secretome of the fungal pathogen Aspergillus fumigatus.

    Directory of Open Access Journals (Sweden)

    Margaret V Powers-Fletcher

    Full Text Available Calnexin is a membrane-bound lectin chaperone in the endoplasmic reticulum (ER that is part of a quality control system that promotes the accurate folding of glycoproteins entering the secretory pathway. We have previously shown that ER homeostasis is important for virulence of the human fungal pathogen Aspergillus fumigatus, but the contribution of calnexin has not been explored. Here, we determined the extent to which A. fumigatus relies on calnexin for growth under conditions of environmental stress and for virulence. The calnexin gene, clxA, was deleted from A. fumigatus and complemented by reconstitution with the wild type gene. Loss of clxA altered the proteolytic secretome of the fungus, but had no impact on growth rates in either minimal or complex media at 37°C. However, the ΔclxA mutant was growth impaired at temperatures above 42°C and was hypersensitive to acute ER stress caused by the reducing agent dithiothreitol. In contrast to wild type A. fumigatus, ΔclxA hyphae were unable to grow when transferred to starvation medium. In addition, depleting the medium of cations by chelation prevented ΔclxA from sustaining polarized hyphal growth, resulting in blunted hyphae with irregular morphology. Despite these abnormal stress responses, the ΔclxA mutant remained virulent in two immunologically distinct models of invasive aspergillosis. These findings demonstrate that calnexin functions are needed for growth under conditions of thermal, ER and nutrient stress, but are dispensable for surviving the stresses encountered in the host environment.

  19. Zebrafish Noxa promotes mitosis in early embryonic development and regulates apoptosis in subsequent embryogenesis.

    Science.gov (United States)

    Zhong, J-X; Zhou, L; Li, Z; Wang, Y; Gui, J-F

    2014-06-01

    Noxa functions in apoptosis and immune system of vertebrates, but its activities in embryo development remain unclear. In this study, we have studied the role of zebrafish Noxa (zNoxa) by using zNoxa-specifc morpholino knockdown and overexpression approaches in developing zebrafish embryos. Expression pattern analysis indicates that zNoxa transcript is of maternal origin, which displays a uniform distribution in early embryonic development until shield stage, and the zygote zNoxa transcription is initiated from this stage and mainly localized in YSL of the embryos. The zNoxa expression alterations result in strong embryonic development defects, demonstrating that zNoxa regulates apoptosis from 75% epiboly stage of development onward, in which zNoxa firstly induces the expression of zBik, and then cooperates with zBik to regulate apoptosis. Moreover, zNoxa knockdown also causes a reduction in number of mitotic cells before 8 h.p.f., suggesting that zNoxa also promotes mitosis before 75% epiboly stage. The effect of zNoxa on mitosis is mediated by zWnt4b in early embryos, whereas zMcl1a and zMcl1b suppress the ability of zNoxa to regulate mitosis and apoptosis at different developmental stages. In addition, mammalian mouse Noxa (mNoxa) mRNA was demonstrated to rescue the arrest of mitosis when zNoxa was knocked down, suggesting that mouse and zebrafish Noxa might have similar dual functions. Therefore, the current findings indicate that Noxa is a novel regulator of early mitosis before 75% epiboly stage when it translates into a key mediator of apoptosis in subsequent embryogenesis.

  20. Mevalonate cascade regulation of airway mesenchymal cell autophagy and apoptosis: a dual role for p53.

    Directory of Open Access Journals (Sweden)

    Saeid Ghavami

    Full Text Available Statins inhibit the proximal steps of cholesterol biosynthesis, and are linked to health benefits in various conditions, including cancer and lung disease. We have previously investigated apoptotic pathways triggered by statins in airway mesenchymal cells, and identified reduced prenylation of small GTPases as a primary effector mechanism leading to p53-mediated cell death. Here, we extend our studies of statin-induced cell death by assessing endpoints of both apoptosis and autophagy, and investigating their interplay and coincident regulation. Using primary cultured human airway smooth muscle (HASM and human airway fibroblasts (HAF, autophagy, and autophagosome formation and flux were assessed by transmission electron microscopy, cytochemistry (lysosome number and co-localization with LC3 and immunoblotting (LC3 lipidation and Atg12-5 complex formation. Chemical inhibition of autophagy increased simvastatin-induced caspase activation and cell death. Similarly, Atg5 silencing with shRNA, thus preventing Atg5-12 complex formation, increased pro-apoptotic effects of simvastatin. Simvastatin concomitantly increased p53-dependent expression of p53 up-regulated modulator of apoptosis (PUMA, NOXA, and damage-regulated autophagy modulator (DRAM. Notably both mevalonate cascade inhibition-induced autophagy and apoptosis were p53 dependent: simvastatin increased nuclear p53 accumulation, and both cyclic pifithrin-α and p53 shRNAi partially inhibited NOXA, PUMA expression and caspase-3/7 cleavage (apoptosis and DRAM expression, Atg5-12 complex formation, LC3 lipidation, and autophagosome formation (autophagy. Furthermore, the autophagy response is induced rapidly, significantly delaying apoptosis, suggesting the existence of a temporally coordinated p53 regulation network. These findings are relevant for the development of statin-based therapeutic approaches in obstructive airway disease.

  1. Autophagy regulates chlorpyrifos-induced apoptosis in SH-SY5Y cells

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jae Hyeon [Department of Pharmacology, College of Medicine, Hanyang University (Korea, Republic of); Hanyang Biomedical Research Institute, Seoul (Korea, Republic of); Graduate School of Biomedical Science and Engineering, Hanyang University, Seoul (Korea, Republic of); Lee, Jeong Eun [Department of Pharmacology, College of Medicine, Hanyang University (Korea, Republic of); Hanyang Biomedical Research Institute, Seoul (Korea, Republic of); Shin, In Chul [Department of Pharmacology, College of Medicine, Hanyang University (Korea, Republic of); Koh, Hyun Chul, E-mail: hckoh@hanyang.ac.kr [Department of Pharmacology, College of Medicine, Hanyang University (Korea, Republic of); Hanyang Biomedical Research Institute, Seoul (Korea, Republic of); Graduate School of Biomedical Science and Engineering, Hanyang University, Seoul (Korea, Republic of)

    2013-04-01

    Recent studies have shown that up-regulation of autophagy may be a tractable therapeutic intervention for clearing disease-causing proteins, including α-synuclein, ubiquitin, and other misfolded or aggregated proteins in pesticide-induced neurodegeneration. In a previous study, we reported that chlorpyrifos (CPF)-induced mitochondria-dependent apoptosis is mediated through reactive oxygen species in SH-SY5Y cells. In this study, we explored a novel pharmacotherapeutic approach to prevent CPF neurotoxicity involving the regulation of autophagy. We investigated the modulation of CPF-induced apoptosis according to autophagy regulation. We found that CPF induced apoptosis in SH-SY5Y cells, as demonstrated by the activation of caspase-3 and nuclear condensation. In addition, we observed that cells treated with CPF underwent autophagic cell death by monitoring the expression of LC3-II and p62. Pretreatment with the autophagy inducer rapamycin significantly enhanced the cell viability of CPF-exposed cells, and the enhancement of cell viability was partially due to alleviation of CPF-induced apoptosis via a decrease in levels of cleaved caspase-3. Specifically, rapamycin pretreatment decreased Bax and increased Bcl-2 expression in mitochondria. In addition, rapamycin significantly decreased cytochrome c release in from mitochondria into the cytosol. However, pretreatment of cells with the autophagy inhibitor, 3-methyladenine (3MA), remarkably increased CPF toxicity in these cells; this with correlated with increased expression of Bax and decreased expression of Bcl-2 in mitochondria. Our results suggest that CPF-induced cytotoxicity is modified by autophagy regulation and that rapamycin protects against CPF-induced apoptosis by enhancing autophagy. Pharmacologic induction of autophagy by rapamycin may be a useful treatment strategy in neurodegenerative disorders. - Highlights: ► Chlorpyrifos (CPF) is cytotoxic to SH-SY5Y cells ► CPF-induced cytotoxicity is mediated by

  2. Differential regulation of survivin by p53 contributes to cell cycle dependent apoptosis

    Institute of Scientific and Technical Information of China (English)

    Yan JIN; Yong WEI; Lei XIONG; Ying YANG; Jia Rui WU

    2005-01-01

    Recent studies indicate that cell-cycle checkpoints are tightly correlated with the regulation of apoptosis, in which p53 plays an important role. Our present works show that the expression of E6/E7 oncogenes of human papillomavirus in HeLa cells is inhibited in the presence of anti-tumor reagent tripchlorolide (TC), which results in the up-regulation of p53 in HeLa cells. Interestingly, under the same TC-treatment, the cells at the early S-phase are more susceptible to apoptosis than those at the middle S-phase although p53 protein is stabilized to the same level in both situations.Significant difference is exhibited between the two specified expression profiles. Further analysis demonstrates that anti-apoptotic gene survivin is up-regulated by p53 in the TC-treated middle-S cells, whereas it is down-regulated by p53 in the TC-treated early-S cells. Taken together, the present study indicates that the differential p53-regulated expression of survivin at different stages of the cell cycle results in different cellular outputs under the same apoptosis-inducer.

  3. Proteomics analysis of apoptosis-regulating proteins in tissues with different radiosensitivity

    International Nuclear Information System (INIS)

    The aim of this study was to identify of radiosusceptibility proteins in tissues with different radiosensitivity. C3H/HeJ mice were exposed to 10 Gy. The tissues were processed for proteins extraction and were analyzed by 2-dimensional electrophoresis. The proteins were identified by matrix-assisted laser desorption ionizing time-of-flight mass spectrometry and validated by immunohistochemical staining and Western blotting. The peaks of apoptosis levels were 35.3±1.7% and 0.6±0.2% in the spleen and the liver, respectively, after ionizing radiation. Analysis of liver tissue showed that the expression level of reactive oxygen species (ROS) related proteins such as cytochrome c, glutathione S transferase, NADH dehydrogenase and peroxiredoxin VI increased after radiation. The expression level of cytochrome c increased to 3-fold after ionizing radiation in both tissues. However in spleen tissue, the expression level of various kinds of apoptosis regulating proteins increased after radiation. These involved iodothyronine, CD 59A glycoprotein precursor, fas antigen and tumor necrosis factor -inducible protein TSG-6nprecursor after radiation. The difference in the apoptosis index between the liver and spleen tissues is closely associated with the expression of various kinds of apoptosis-related proteins. The result suggests that the expression of apoptosis-related protein and redox proteins play important roles in this radiosusceptibility. (author)

  4. Regulation of Histone Acetylation and Apoptosis by Trichostatin in HL-60 Cells

    Institute of Scientific and Technical Information of China (English)

    李新刚; 陈维凯; 谷俊侠; 崔国惠; 陈燕

    2004-01-01

    In order to examine the strong anticancer action and low toxicity of Trichostatin A(TSA), the effect of TSA was examined on the growth inhibition, acetylation of histone H3 and apoptosis in HL-60 cells by employing MTT, immunocytochemical techniques, and Annexin-V-FITC/PI assay. Our results showed that TSA could inhibit proliferation of HL- 60 cells in a time- and dose-dependent manner, and the IC50 at the 36th h was 100 ng/ml. The apoptosis-inducing effect of TSA on HL-60 cells was also time- and dose-dependent. But it didn't demonstrate apparent apoptosis induction in NPBMNCs within specific dose and time range. Both of the acetylation of histone H3 in HL-60 cells and NPBMNCs increased significantly (P<0.05) after treated with 100 ng/ml TSA for 4 h. However, there was no significant differences between the two groups (P>0.05). It is concluded that TSA can inhibit growth and induce apoptosis of HL-60 cells in a time- and dosedependent manner, and is able to selectively induce apoptosis in HL-60 cells but does not respond in NPBMNCs under the same conditions. The difference of TSA between HL-60 cells and NPBMNCs can't be explained by the regulation of histone acetylation.

  5. Paclitaxel Induces Apoptosis in Breast Cancer Cells through Different Calcium—Regulating Mechanisms Depending on External Calcium Conditions

    OpenAIRE

    Zhi Pan; Andrew Avila; Lauren Gollahon

    2014-01-01

    Previously, we reported that endoplasmic reticulum calcium stores were a direct target for paclitaxel initiation of apoptosis. Furthermore, the actions of paclitaxel attenuated Bcl-2 resistance to apoptosis through endoplasmic reticulum-mediated calcium release. To better understand the calcium-regulated mechanisms of paclitaxel-induced apoptosis in breast cancer cells, we investigated the role of extracellular calcium, specifically; whether influx of extracellular calcium contributed to and...

  6. Homoharringtonine induces apoptosis of endothelium and down-regulates VEGF expression of K562 cells

    Institute of Scientific and Technical Information of China (English)

    叶琇锦; 林茂芳

    2004-01-01

    Homoharringtonine (HHT) has currently been used successfully in the treatment of acute and chronic myeloid leukemias and has been shown to induce apoptosis of different types of leukemic cells in vitro. Emerging evidence suggests that angiogenesis may play an important role in hematological malignancies, such as leukemia. However, whether HHT can relieve leukemia by anti-angiogenesis is still unknown. We investigated the anti-angiogenesis potential of HHT with the human umbilical vein endothelial cell line (ECV304) and leukemic cell line (K562) in vitro. Cellular proliferation was determined by MTT assay and apoptosis was analyzed by flow cytometry, The mRNA expression of vascular endothelial growth factor (VEGF) was assessed by RT-PCR and VEGF protein production was detected by Western blot. Inhibition of cell proliferation and induction of apoptosis by HHT were discovered in ECV304 cells, and appeared in a dose- and time-dependent manner, Also, treatment with HHT caused down-regulation of VEGF mRNA expression in K562 cells in similar dose- and time-dependent manner and inhibition of VEGF protein production in K562 cells in response to the enhancing concentration of HHT. The results demonstrated that HHT could also induce apoptosis in endothelium and down-regulate VEGF expression in K562 cells. In conclusion, we believe HHT has anti-angiogenesis potential and speculate that HHT might exert its anti-leukemia effects via reduction of angiogenesis.

  7. DOWN-REGULATION OF CYTOKINE SECRETION AND REPRESSION OF APOPTOSIS hDaxx IN MACROPHAGES

    Institute of Scientific and Technical Information of China (English)

    LIU An-yuan; WAN Yan-ping; TAN Li-zhi; WU Yi-mou; YU Min-jun; LIU Chuan-ai; Yin Wei-guo

    2005-01-01

    Objective: To investigate the regulation effects on LPS-mediated cytokine secretion and dexamethasone- induced apoptosis in macrophages by transient overexpression of hDaxx. Methods: An eukaryotic expression vector pEGFP/hDaxx, which could express a fusion protein GFP-Daxx, was transfected into macrophages. The expression and localization of GFP-hDaxx fusion protein was analyzed by fluorescent microscope and western blot. The effects of transient overexpression of GFP-hDaxx fusion protein on the lipopolysaccharide(LPS)-mediated secretion of TNF-( and IL-1( were determined by ELISA. Moreover, the dexamethasone-induced apoptosis was determined morphologically by Giemsa stain. Results: The results observed showed that GFP-hDaxx fusion protein overexpressed in macrophages and localized in nuclei but GFP in cytoplasm under fluorescent microscope. The overexpression of GFP-hDaxx fusion protein could be detected by Western blot with an antibody against C-terminal of hDaxx. In the group with overexpressed GFP-hDaxx fusion protein, the LPS-mediated cytokine secretion decreased remarkably at 1 h, 3 h, 6 h respectively after LPS stimulation, and the dexamethasone- induced apoptosis reduced notably at 6 h, 12 h and 24 h respectively after addition of dexamethasone. There were remarkable difference between pEGFP/hDaxx group and control group (P<0.01) at different time. Conclusion: Transient overexpression of hDaxx down-regulates LPS-mediated cytokine secretion in macrophages and inhibits dexamethasone-induced macrophages apoptosis.

  8. Human neuronal apoptosis secondary to traumatic brain injury and the regulative role of apoptosis-related genes

    Institute of Scientific and Technical Information of China (English)

    杨树源; 雪亮

    2004-01-01

    Objective: To observe human neuronal apoptosis secondary to traumatic brain injury, and to elucidate its regulative mechanism and the change of expression of apoptosis-related genes.Methods: Specimens of brain were collected from cases of traumatic brain injury in humans. The histological and cellular morphology was examined by light and electron microscopy. The extent of DNA injury to cortical neurons was detected by using TUNEL. By in situ hybridisation and immunohistochemistry the mRNA changes and protein expression of Bcl-2, Bax, p53, and caspase 3 p20 subunit were observed.Results: Apoptotic neurons appeared following traumatic brain injury, peaked at 24 hours and lasted for 7 days. In normal brain tissue activated caspase 3 was rare,but a short time after trauma it became activated. The activity peaked at 20-28 hours and remained higher than normal for 5-7 days. There was no expression of Bcl-2 mRNA and Bcl-2 protein in normal brain tissue but 8 hours after injury their expression became evident and then increased, peaked at 2-3 days and remained higher than normal for 5-7 days. The primary expression of Bax-mRNA and Bax protein was high in normal brain tissue. At 20-28 hours they increased and remained high for 2-3 days; on the 7th days they returned to a normal level. In normal brain tissue, p53mRNA and P53 were minimally expressed.Increased expression was detected at the 8th hour, and decreased at 20-28 hours but still remained higher than normal on the 5th day.Conclusions: Following traumatic injury to the human brain, apoptotic neurons appear around the focus of trauma. The mRNA and protein expression of Bcl-2, Bax and p53 and the activity of caspase 3 enzyme are increased.

  9. Eurycomanone induce apoptosis in HepG2 cells via up-regulation of p53

    Directory of Open Access Journals (Sweden)

    Zakaria Yusmazura

    2009-06-01

    Full Text Available Abstract Background Eurycomanone is a cytotoxic compound found in Eurycoma longifolia Jack. Previous studies had noted the cytotoxic effect against various cancer cell lines. The aim of this study is to investigate the cytotoxicity against human hepato carcinoma cell in vitro and the mode of action. The cytotoxicity of eurycomanone was evaluated using MTT assay and the mode of cell death was detected by Hoechst 33258 nuclear staining and flow cytometry with Annexin-V/propidium iodide double staining. The protein expression Bax, Bcl-2, p53 and cytochrome C were studied by flow cytometry using a spesific antibody conjugated fluorescent dye to confirm the up-regulation of p53 and Bax in cancer cells. Results The findings suggested that eurycomanone was cytotoxic on cancerous liver cell, HepG2 and less toxic on normal cells Chang's liver and WLR-68. Furthermore, various methods proved that apoptosis was the mode of death in eurycomanone-treated HepG2 cells. The characteristics of apoptosis including chromatin condensation, DNA fragmentation and apoptotic bodies were found following eurycomanone treatment. This study also found that apoptotic process triggered by eurycomanone involved the up-regulation of p53 tumor suppressor protein. The up-regulation of p53 was followed by the increasing of pro-apoptotic Bax and decreasing of anti-apoptotic Bcl-2. The increased of cytochrome C levels in cytosol also results in induction of apoptosis. Conclusion The data suggest that eurycomanone was cytotoxic on HepG2 cells by inducing apoptosis through the up-regulation of p53 and Bax, and down-regulation of Bcl-2.

  10. E2F-1 induces melanoma cell apoptosis via PUMA up-regulation and Bax translocation

    International Nuclear Information System (INIS)

    PUMA is a pro-apoptotic Bcl-2 family member that has been shown to be involved in apoptosis in many cell types. We sought to ascertain whether induction of PUMA plays a crucial role in E2F-1-induced apoptosis in melanoma cells. PUMA gene and protein expression levels were detected by real-time PCR and Western blot in SK-MEL-2 and HCT116 cell lines after Ad-E2F-1 infection. Activation of the PUMA promoter by E2F-1 overexpression was detected by dual luciferase reporter assay. E2F-1-induced Bax translocation was shown by immunocytochemistry. The induction of caspase-9 activity was measured by caspase-9 colorimetric assay kit. Up-regulation of the PUMA gene and protein by E2F-1 overexpression was detected by real-time PCR and Western blot analysis in the SK-MEL-2 melanoma cell line. In support of this finding, we found six putative E2F-1 binding sites within the PUMA promoter. Subsequent dual luciferase reporter assay showed that E2F-1 expression could increase the PUMA gene promoter activity 9.3 fold in SK-MEL-2 cells. The role of PUMA in E2F-1-induced apoptosis was further investigated in a PUMA knockout cell line. Cell viability assay showed that the HCT116 PUMA-/- cell line was more resistant to Ad-E2F-1-mediated cell death than the HCT116 PUMA+/+ cell line. Moreover, a 2.2-fold induction of the PUMA promoter was also noted in the HCT116 PUMA+/+ colon cancer cell line after Ad-E2F-1 infection. Overexpression of a truncated E2F-1 protein that lacks the transactivation domain failed to up-regulate PUMA promoter, suggesting that PUMA may be a transcriptional target of E2F-1. E2F-1-induced cancer cell apoptosis was accompanied by Bax translocation from the cytosol to mitochondria and the induction of caspase-9 activity, suggesting that E2F-1-induced apoptosis is mediated by PUMA through the cytochrome C/Apaf-1-dependent pathway. Our studies strongly demonstrated that E2F-1 induces melanoma cell apoptosis via PUMA up-regulation and Bax translocation. The signaling

  11. Osteocyte apoptosis regulates osteoclast precursor adhesion via osteocytic IL-6 secretion and endothelial ICAM-1 expression.

    Science.gov (United States)

    Cheung, Wing-Yee; Simmons, Craig A; You, Lidan

    2012-01-01

    Osteocyte apoptosis precedes osteoclast resorption, and may act as a critical signal to trigger bone remodeling. While osteoclast precursors are known to travel via the circulation, the specific mechanisms by which they accumulate at remodeling sites are unclear. We hypothesized that osteocyte apoptosis mediates osteoclast precursor adhesion to vascular endothelium by regulating osteocytic secretion of IL-6 and soluble IL-6 receptor (sIL-6R) to promote endothelial ICAM-1 expression. We found that conditioned media from TNF-α-induced apoptotic MLO-Y4 osteocytes promoted RAW264.7 osteoclast precursor adhesion onto D4T endothelial cells (P<0.05). Blocking osteocyte apoptosis with a pan-caspase inhibitor (ZVAD-FMK) reduced osteoclast precursor adhesion to baseline levels (P<0.001). Endothelial cells treated with apoptotic osteocyte conditioned media had elevated surface expression of ICAM-1 (P<0.05), and blocking ICAM-1 abolished apoptosis-induced osteoclast precursor adhesion. Apoptotic osteocyte conditioned media contained more IL-6 (P<0.05) and sIL-6R (P<0.05) than non-apoptotic osteocyte conditioned media. When added exogenously, both IL-6 and sIL-6R were required for endothelial activation, and blocking IL-6 reduced apoptosis-induced osteoclast precursor adhesion to baseline levels (P<0.05). Therefore, we conclude that osteocyte apoptosis can promote osteoclast precursor adhesion to endothelial cells via ICAM-1; this is likely through increased osteocytic IL-6 and sIL-6R secretion, both of which are indispensible to endothelial activation. PMID:21986000

  12. NEW EMBO MEMBER’S REVIEW: Viral and bacterial proteins regulating apoptosis at the mitochondrial level

    OpenAIRE

    Boya, Patricia; Roques, Bernard,; Kroemer, Guido

    2001-01-01

    Mitochondrial membrane permeabilization (MMP) is a critical step of several apoptotic pathways. Some infectious intracellular pathogens can regulate (induce or inhibit) apoptosis of their host cells at the mitochondrial level, by targeting proteins to mitochondrial membranes that either induce or inhibit MMP. Pathogen-encoded mitochondrion-targeted proteins may or may not show amino acid sequence homology to Bcl-2-like proteins. Among the Bcl-2-unrelated, mitochondrion-targeted proteins, seve...

  13. ZEB2 mediates multiple pathways regulating cell proliferation, migration, invasion, and apoptosis in glioma.

    Directory of Open Access Journals (Sweden)

    Songtao Qi

    Full Text Available BACKGROUND: The aim of the present study was to analyze the expression of Zinc finger E-box Binding homeobox 2 (ZEB2 in glioma and to explore the molecular mechanisms of ZEB2 that regulate cell proliferation, migration, invasion, and apoptosis. METHODOLOGY/PRINCIPAL FINDINGS: Expression of ZEB2 in 90 clinicopathologically characterized glioma patients was analyzed by immunohistochemistry. Furthermore, siRNA targeting ZEB2 was transfected into U251 and U87 glioma cell lines in vitro and proliferation, migration, invasion, and apoptosis were examined separately by MTT assay, Transwell chamber assay, flow cytometry, and western blot. RESULTS: The expression level of ZEB2 protein was significantly increased in glioma tissues compared to normal brain tissues (P<0.001. In addition, high levels of ZEB2 protein were positively correlated with pathology grade classification (P = 0.024 of glioma patients. Knockdown of ZEB2 by siRNA suppressed cell proliferation, migration and invasion, as well as induced cell apoptosis in glioma cells. Furthermore, ZEB2 downregulation was accompanied by decreased expression of CDK4/6, Cyclin D1, Cyclin E, E2F1, and c-myc, while p15 and p21 were upregulated. Lowered expression of ZEB2 enhanced E-cadherin levels but also inhibited β-Catenin, Vimentin, N-cadherin, and Snail expression. Several apoptosis-related regulators such as Caspase-3, Caspase-6, Caspase-9, and Cleaved-PARP were activated while PARP was inhibited after ZEB2 siRNA treatment. CONCLUSION: Overexpression of ZEB2 is an unfavorable factor that may facilitate glioma progression. Knockdown ZEB2 expression by siRNA suppressed cell proliferation, migration, invasion and promoted cell apoptosis in glioma cells.

  14. Down-regulation of HSP27 sensitizes TRAIL-resistant tumor cell to TRAIL-induced apoptosis

    DEFF Research Database (Denmark)

    Zhuang, Hongqin; Jiang, Weiwei; Cheng, Wei;

    2010-01-01

    Tumor necrosis factor-alpha-related apoptosis-inducing ligand (TRAIL) has recently emerged as a cancer therapeutic agent because it preferentially induces apoptosis in human cancer over normal cells. Most tumor cells, including lung cancer cell line A549, unfortunately, are resistant to TRAIL...... siRNA on drug sensitization of A549 cells to TRAIL treatment. The results showed that treatment of A549 cells with HSP27 siRNA down-regulated HSP27 expression but did not induce significant apoptosis. However, combination of HSP27 siRNA with TRAIL-induced significant apoptosis in TRAIL-resistant A549...... cells. In addition to inducing caspases activation and apoptosis, combined treatment with HSP27 siRNA and TRAIL also increased JNK and p53 expression and activity. Collectively, these findings provide a conclusion that siRNA targeting of the HSP27 gene specifically down-regulated HSP27 expression in A...

  15. Cell cycle and apoptosis regulation by NFAT transcription factors: new roles for an old player.

    Science.gov (United States)

    Mognol, G P; Carneiro, F R G; Robbs, B K; Faget, D V; Viola, J P B

    2016-01-01

    The NFAT (nuclear factor of activated T cells) family of transcription factors consists of four Ca(2+)-regulated members (NFAT1-NFAT4), which were first described in T lymphocytes. In addition to their well-documented role in T lymphocytes, where they control gene expression during cell activation and differentiation, NFAT proteins are also expressed in a wide range of cells and tissue types and regulate genes involved in cell cycle, apoptosis, angiogenesis and metastasis. The NFAT proteins share a highly conserved DNA-binding domain (DBD), which allows all NFAT members to bind to the same DNA sequence in enhancers or promoter regions. The same DNA-binding specificity suggests redundant roles for the NFAT proteins, which is true during the regulation of some genes such as IL-2 and p21. However, it has become increasingly clear that different NFAT proteins and even isoforms can have unique functions. In this review, we address the possible reasons for these distinct roles, particularly regarding N- and C-terminal transactivation regions (TADs) and the partner proteins that interact with these TADs. We also discuss the genes regulated by NFAT during cell cycle regulation and apoptosis and the role of NFAT during tumorigenesis. PMID:27100893

  16. 3-Bromopyruvate and sodium citrate induce apoptosis in human gastric cancer cell line MGC-803 by inhibiting glycolysis and promoting mitochondria-regulated apoptosis pathway.

    Science.gov (United States)

    Guo, Xingyu; Zhang, Xiaodong; Wang, Tingan; Xian, Shulin; Lu, Yunfei

    2016-06-17

    Cancer cells are mainly dependent on glycolysis to generate adenosine triphosphate (ATP) and intermediates required for cell growth and proliferation. Thus, inhibition of glycolysis might be of therapeutic value in antitumor treatment. Our previously studies had found that both 3-bromopyruvate (BP) and sodium citrate (SCT) can inhibit tumor growth and proliferation in vitro and in vivo. However, the mechanism involved in the BP and SCT mediated antitumor activity is not entirely clear. In this work, it is demonstrated that BP inhibits the enzyme hexokinase (HK) activity and SCT suppresses the phosphofructokinase (PFK) activity respectively, both the two agents decrease viability, ATP generation and lactate content in the human gastric cancer cell line MGC-803. These effects are directly correlated with blockage of glycolysis. Furthermore, BP and SCT can induce the characteristic manifestations of mitochondria-regulated apoptosis, such as down-regulation of anti-apoptosis proteins Bcl-2 and Survivin, up-regulation of pro-apoptosis protein Bax, activation of caspase-3, as well as leakage of cytochrome c (Cyt-c). In summary, our results provided evidences that BP and SCT inhibit the MGC-803 cells growth and proliferation might be correlated with inhibiting glycolysis and promoting mitochondria-regulated apoptosis. PMID:27163639

  17. Effects of AMPK on high glucose stimulated apoptosis of endothelial cells via regulation of calcium influx

    Directory of Open Access Journals (Sweden)

    Ting LU

    2015-11-01

    Full Text Available Objective To investigate the inhibitory effect of adenosine monophosphate (AMP-dependent protein kinase (AMPK on high glucose-stimulated endothelial cell apoptosis and its mechanism. Methods MS-1 endothelial cells were cultured in vitro, and they were treated with AMPK agonist, AMPK inhibitor, 2-APB (a blocker of store operated Ca2+ channel (SOCC and (or high glucose, and a control group without any intervention were set up. TUNEL assay was performed to determine apoptotic cells. Laser scanning confocal microscopy was used to assess the Ca2+ influx into cells, and Western-blotting was performed to determine the expressions of Stim1 and Orai1 of the store operated Ca2+ channel (SOCC proteins. Results Apoptosis of endothelial cells was induced significantly, and the expressions of Stim1 and Orai1 were upregulated in high glucose group compared with that in control group (P<0.05. The rate of apoptosis of high glucose-induced endothelial cell was found to be increased in AMPK inhibitor group and decreased in AMPK agonist group, and the expressions of Stim1 and Orai1 were found to be down-regulated in AMPK agonist group as compared with that in high glucose group (P<0.05. Compared with the control group, high glucose stimulation significantly induced the Ca2+ influx to endothelial cells; compared with high glucose group, 2-APB significantly inhibited high glucose-induced Ca2+ influx to endothelial cells, and blocked the inducing effect of high-glucose on endothelial cell apoptosis. Compared with high glucose group, AMPK agonist significantly inhibited high glucose-induced cell Ca2+ influx. Conclusion By reducing the expressions of Stim1 and Orai1, AMPK may inhibit SOCC-mediated Ca2+ influx, and block the high glucose-stimulated endothelial cell apoptosis, thus play an important protective role in sustaining endothelial cell function. DOI: 10.11855/j.issn.0577-7402.2015.10.01

  18. Regulation of Ceramide Synthase-Mediated Crypt Epithelium Apoptosis by DNA Damage Repair Enzymes

    Science.gov (United States)

    Rotolo, Jimmy A.; Mesicek, Judith; Maj, Jerzy; Truman, Jean-Philip; Haimovitz-Friedman, Adriana; Kolesnick, Richard; Fuks, Zvi

    2015-01-01

    Acute endothelial cell apoptosis and microvascular compromise couple GI tract irradiation to reproductive death of intestinal crypt stem cell clonogens (SCCs) following high-dose radiation. Genetic or pharmacologic inhibition of endothelial apoptosis prevents intestinal damage, but as the radiation dose is escalated, SCCs become directly susceptible to an alternate cell death mechanism, mediated via ceramide synthase (CS)-stimulated de novo synthesis of the pro-apoptotic sphingolipid ceramide, and p53-independent apoptosis of crypt SCCs. We previously reported that ATM deficiency resets the primary radiation lethal pathway, allowing CS-mediated apoptosis at the low-dose range of radiation. The mechanism for this event, termed target reordering, remains unknown. Here we show that inactivation of DNA damage repair pathways signal CS-mediated apoptosis in crypt SCCs, presumably via persistent unrepaired DNA double strand breaks (DSBs). Genetic loss-of-function of sensors and transducers of DNA DSB repair confers the CS-mediated lethal pathway in intestines of sv129/B6Mre11ATLD1/ATLD1 and C57BL/6Prkdc/SCID (SCID) mice exposed to low-dose radiation. In contrast, CS-mediated SCC lethality was mitigated in irradiated gain-of-function Rad50S/S mice, and epistasis studies order Rad50 upstream of Mre11. These studies suggest unrepaired DNA DSBs as causative in target re-ordering in intestinal SCCs. As such, we provide an in vivo model of DNA damage repair that is standardized, can be exploited to understand allele-specific regulation in intact tissue, and is pharmacologically tractable. PMID:20086180

  19. RhoA/ROCK pathway regulates hypoxia-induced myocardial cell apoptosis

    Institute of Scientific and Technical Information of China (English)

    Yi Huang; Jiang-bin Chen; Bo Yang; Hui Shen; Jin-Jun Liang; Qiong Luo

    2014-01-01

    Objective:To observe the regulatory effects of RhoA/ROCK pathway on the apoptosis of cardiac myocyte induced by anoxia and its mechanism. Methods:The model of cardiac myocyte anoxia was established. The beat pulsations and apoptosis rates after 1 h, 3 h, 6 h, 9 h and 12 h of anoxia were recorded and the expressions of RhoA, ROCK1/2, p-PI3K, p-AKT and caspae-3 were detected, too. The apoptosis and the expressions of related proteins were detected after RNAi of RhoA and the inhibition of ROCK by Y-27632. Results:The beat pulsations after 1 h, 3 h, 6 h, 9 h and 12 h decreased gradually but the apoptosis rates increased gradually, and the expressions of RhoA, ROCK1/2, p-PI3K, p-AKT and caspase-3 were increasing along with the increasing duration of anoxia. The apoptotic rates after 1 h, 3 h, 6 h, 9 h and 12 h of anoxia were (4.36±0.98)%, (8.36±2.12)%, (15.32±3.62)%, (18.68±4.83)%and (24.56±6.22)%, respectively and decreased more significantly than control group in different time points of anoxia (P<0.05), and the expressions of RhoA, ROCK1/2, p-PI3K, p-AKT and caspase-3 decreased significantly (P<0.05). The apoptosis rate and the expressions of RhoA, ROCK1/2, p-PI3K, p-AKT and caspase-3 decreased significantly (P<0.05) after the inhibition of ROCK by Y-27632 (P<0.05). Conclusions:RhoA/ROCK pathway plays a critical role in the regulation of the apoptosis of cardiac myocyte induced by anoxia, which may be accompanied by regulating the activity of PI3K/AKT/Caspase-3 pathway.

  20. 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.

  1. 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.

  2. TIP30 regulates apoptosis-related genes in its apoptotic signal transduction pathway

    Institute of Scientific and Technical Information of China (English)

    Mei Shi; Xia Zhang; Ping Wang; Hong-Wei Zhang; Bai-He Zhang; Meng-Chao Wu

    2005-01-01

    AIM: To investigate the role of TIP30 in apoptotic signal pathway in hepatoblastoma cells and to provide a basis for TIP30 as a gene therapy candidate in the regression of hepatoblastoma cells.METHODS: Apoptosis of human hepatoblastoma cell lines HepG2 (p53 wild), Hep3B (p53 null) and PLC/RPF/5 (p53mutant) infected with Ad-TIP30 (bearing a wild type human Tip30 gene) were analyzed and p53, Bax and Bclxl expression levels were compared among these cells.MlT assay, DNA fragmentation, in situ 3' end labeling of DNA, annexin-Ⅴ FITC staining were used to detect cell death and apoptosis in cells at various time intervals subsequent to infection, and to determine whether TIP30 had an effect on the expression levels of some apoptosis-related gene products such as Bax, p53 and Bcl-xl. A similar time course experiment was performed by Western blotting.RESULTS: In MTT assay, the viability of HepG2 cells decreased significantly from 99.7% to 10% and displayed more massive cell death within 5-8 d than Hep3B and PLC/RPF/5 cells, with their viability decreased from 97.8% to 44.3% and 98.1% to 50.4%, respectively. In annexin-ⅤFITC assay, the percentage of apoptosis cells in HepG2cells was two to three-fold higher than that in control cells (infected with Ad-GFP), two-fold higher than that in Hep3B cells and 1.4-fold higher than that in PLC/RPF/5 cells 36 h after infection, respectively. Moreover, in HepG2 cells, the p53 began to increase 6-8 h after infection, reaching a maximum level between 8 and 12 h after infection and then dropped. Bax showed a similar increase in the cells as p53 reached the maximum at 8-12 h and subsequently decreased. Interestingly, Bcl-xl protein levels were down regulated during 24 to 36 h after Ad-TIP30 infection. In contrast, ectopic expression of TIP30 in Hep3B and PLC/RPF/5 cells had no effect on the regulation of Bax expression, but had an effect on Bcl-xl levels. In comparison with HepG2 cells, these data suggested that up-regulation of p53

  3. Induction of Apoptosis by 11-Dehydrosinulariolide via Mitochondrial Dysregulation and ER Stress Pathways in Human Melanoma Cells

    Directory of Open Access Journals (Sweden)

    Jeff Yi-Fu Chen

    2012-08-01

    Full Text Available In this study the isolated compound 11-dehydrosinulariolide from soft coral Sinularia leptoclados possessed anti-proliferative, anti-migratory and apoptosis-inducing activities against A2058 melanoma cells. Anti-tumor effects of 11-dehydrosinulariolide were determined by MTT assay, cell migration assay and flow cytometry. Growth and migration of melanoma cells were dose-dependently inhibited by 2–8 μg/mL 11-dehydrosinulariolide. Flow cytometric data indicated that 11-dehydrosinulariolide induces both early and late apoptosis in melanoma cells. It was found that the apoptosis induced by 11-dehydrosinulariolide is relevant to mitochondrial-mediated apoptosis via caspase-dependent pathways, elucidated by loss of mitochondrial membrane potential (∆Ym, release of cytochrome C, activation of caspase-3/-9 and Bax as well as suppression of Bcl-2/Bcl-xL. The cleavage of PARP-1 suggested partial involvement of caspase-independent pathways. Immunoblotting data displayed up-regulations of PERK/eIF2α/ATF4/CHOP and ATF6/CHOP coupling with elevation of ER stress chaperones GRP78, GRP94, calnexin, calreticulin and PDI, implicating the involvement of these factors in ER stress-mediated apoptosis induced by 11-dehydrosinulariolide. The abolishment of apoptotic events after pre-treatment with salubrinal indicated that ER stress-mediated apoptosis is also induced by 11-dehydrosinulariolide against melanoma cells. The data in this study suggest that 11-dehydrosinulariolide potentially induces apoptosis against melanoma cells via mitochondrial dysregulation and ER stress pathways.

  4. 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.

  5. Specific regulator of eosinophil apoptosis: Siglec-8-new hope for bronchial asthma treatment

    Institute of Scientific and Technical Information of China (English)

    FENG Yin-he; MAO Hui

    2012-01-01

    Objective It is known that Siglec-8 is selectively expressed on human eosinophils at a high level and mediates eosinophil apoptosis when crosslinked with its antibody.The aim of our review is to elucidate the molecular and biological characteristic of Siglec-8 and then discuss the function and possible mechanisms of Siglec-8 in eosinophils.Thereby,we will expand our understanding to the regulation of eosinophil apoptosis,and provide important clues to the treatment of asthma and other hyper-eosinophilic diseases.Data sources Most articles were identified by searching of PubMed online resources using the key term Siglecs.Study selection Mainly original milestone articles and critical reviews written by major pioneer investigators in the field were selected.Results Siglec-8 is selectively expressed on human eosinophil and can specifically induce eosinophil apoptosis.Conclusion The restricted expression of Siglec-8 on human eosinophil and the rapid progress in understanding its role as cell signaling and activation of death receptors have made it an attractive target for treatment of asthma and other hyper-eosinophilic diseases.

  6. Protein Kinase C-δ mediates down-regulation of heterogeneous nuclear ribonucleoprotein K protein: involvement in apoptosis induction

    International Nuclear Information System (INIS)

    We reported previously that NSC606985, a camptothecin analogue, induces apoptosis of acute myeloid leukemia (AML) cells through proteolytic activation of protein kinase C delta (ΔPKC-δ). By subcellular proteome analysis, heterogeneous nuclear ribonucleoprotein K (hnRNP K) was identified as being significantly down-regulated in NSC606985-treated leukemic NB4 cells. HnRNP K, a docking protein for DNA, RNA, and transcriptional or translational molecules, is implicated in a host of processes involving the regulation of gene expression. However, the molecular mechanisms of hnRNP K reduction and its roles during apoptosis are still not understood. In the present study, we found that, following the appearance of the ΔPKC-δ, hnRNP K protein was significantly down-regulated in NSC606985, doxorubicin, arsenic trioxide and ultraviolet-induced apoptosis. We further provided evidence that ΔPKC-δ mediated the down-regulation of hnRNP K protein during apoptosis: PKC-δ inhibitor could rescue the reduction of hnRNP K; hnRNP K failed to be decreased in PKC-δ-deficient apoptotic KG1a cells; conditional induction of ΔPKC-δ in U937T cells directly down-regulated hnRNP K protein. Moreover, the proteasome inhibitor also inhibited the down-regulation of hnRNP K protein by apoptosis inducer and the conditional expression of ΔPKC-δ. More intriguingly, the suppression of hnRNP K with siRNA transfection significantly induced apoptosis. To our knowledge, this is the first demonstration that proteolytically activated PKC-δ down-regulates hnRNP K protein in a proteasome-dependent manner, which plays an important role in apoptosis induction.

  7. Computational Systems Biology Approach Predicts Regulators and Targets of microRNAs and Their Genomic Hotspots in Apoptosis Process.

    Science.gov (United States)

    Alanazi, Ibrahim O; Ebrahimie, Esmaeil

    2016-07-01

    Novel computational systems biology tools such as common targets analysis, common regulators analysis, pathway discovery, and transcriptomic-based hotspot discovery provide new opportunities in understanding of apoptosis molecular mechanisms. In this study, after measuring the global contribution of microRNAs in the course of apoptosis by Affymetrix platform, systems biology tools were utilized to obtain a comprehensive view on the role of microRNAs in apoptosis process. Network analysis and pathway discovery highlighted the crosstalk between transcription factors and microRNAs in apoptosis. Within the transcription factors, PRDM1 showed the highest upregulation during the course of apoptosis, with more than 9-fold expression increase compared to non-apoptotic condition. Within the microRNAs, MIR1208 showed the highest expression in non-apoptotic condition and downregulated by more than 6 fold during apoptosis. Common regulators algorithm showed that TNF receptor is the key upstream regulator with a high number of regulatory interactions with the differentially expressed microRNAs. BCL2 and AKT1 were the key downstream targets of differentially expressed microRNAs. Enrichment analysis of the genomic locations of differentially expressed microRNAs led us to the discovery of chromosome bands which were highly enriched (p < 0.01) with the apoptosis-related microRNAs, such as 13q31.3, 19p13.13, and Xq27.3 This study opens a new avenue in understanding regulatory mechanisms and downstream functions in the course of apoptosis as well as distinguishing genomic-enriched hotspots for apoptosis process.

  8. Paclitaxel Induces Apoptosis in Breast Cancer Cells through Different Calcium—Regulating Mechanisms Depending on External Calcium Conditions

    Directory of Open Access Journals (Sweden)

    Zhi Pan

    2014-02-01

    Full Text Available Previously, we reported that endoplasmic reticulum calcium stores were a direct target for paclitaxel initiation of apoptosis. Furthermore, the actions of paclitaxel attenuated Bcl-2 resistance to apoptosis through endoplasmic reticulum-mediated calcium release. To better understand the calcium-regulated mechanisms of paclitaxel-induced apoptosis in breast cancer cells, we investigated the role of extracellular calcium, specifically; whether influx of extracellular calcium contributed to and/or was necessary for paclitaxel-induced apoptosis. Our results demonstrated that paclitaxel induced extracellular calcium influx. This mobilization of extracellular calcium contributed to subsequent cytosolic calcium elevation differently, depending on dosage. Under normal extracellular calcium conditions, high dose paclitaxel induced apoptosis-promoting calcium influx, which did not occur in calcium-free conditions. In the absence of extracellular calcium an “Enhanced Calcium Efflux” mechanism in which high dose paclitaxel stimulated calcium efflux immediately, leading to dramatic cytosolic calcium decrease, was observed. In the absence of extracellular calcium, high dose paclitaxel’s stimulatory effects on capacitative calcium entry and apoptosis could not be completely restored. Thus, normal extracellular calcium concentrations are critical for high dose paclitaxel-induced apoptosis. In contrast, low dose paclitaxel mirrored controls, indicating that it occurs independent of extracellular calcium. Thus, extracellular calcium conditions only affect efficacy of high dose paclitaxel-induced apoptosis.

  9. Regulation of apoptosis and innate immune stimuli in inflammation-induced preterm labor.

    Science.gov (United States)

    Jaiswal, Mukesh K; Agrawal, Varkha; Mallers, Timothy; Gilman-Sachs, Alice; Hirsch, Emmet; Beaman, Kenneth D

    2013-12-01

    An innate immune response is required for successful implantation and placentation. This is regulated, in part, by the a2 isoform of V-ATPase (a2V) and the concurrent infiltration of M1 (inflammatory) and M2 (anti-inflammatory) macrophages to the uterus and placenta. The objective of the present study was to identify the role of a2V during inflammation-induced preterm labor in mice and its relationship to the regulation of apoptosis and innate immune responses. Using a mouse model of infection-induced preterm delivery, gestational tissues were collected 8 h after intrauterine inoculation on day 14.5 of pregnancy with either saline or peptidoglycan (PGN; a TLR 2 agonist) and polyinosinic-polycytidylic acid [poly(I:C); a TLR3 agonist], modeling Gram-positive bacterial and viral infections, respectively. Expression of a2V decreased significantly in the placenta, uterus, and fetal membranes during PGN+poly(I:C)-induced preterm labor. Expression of inducible NO synthase was significantly upregulated in PGN+poly(I:C)-treated placenta and uterus. PGN+poly(I:C) treatment disturbed adherens junction proteins and increased apoptotic cell death via an extrinsic pathway of apoptosis among uterine decidual cells and spongiotrophoblasts. F4/80(+) macrophages were increased and polarization was skewed in PGN+poly(I:C)-treated uterus toward double-positive CD11c(+) (M1) and CD206(+) (M2) cells, which are critical for the clearance of dying cells and rapid resolution of inflammation. Expression of Nlrp3 and activation of caspase-1 were increased in PGN+poly(I:C)-treated uterus, which could induce pyroptosis. These results suggest that the double hit of PGN+poly(I:C) induces preterm labor via reduction of a2V expression and simultaneous activation of apoptosis and inflammatory processes. PMID:24163412

  10. Apoptosis, necrosis and necroptosis: cell death regulation in the intestinal epithelium.

    Science.gov (United States)

    Günther, Claudia; Neumann, Helmut; Neurath, Markus F; Becker, Christoph

    2013-07-01

    Intestinal epithelial cells (IEC) are organised as a single cell layer which covers the intestine. Their primary task is to absorb nutrients present in the intestinal lumen. However, IEC also play an important role in the immune defence of our body by building a barrier that separates the bowel wall from potentially hazardous bacteria present in the gut lumen. The life cycle of IEC is determined by the time span in which cells migrate from their place of origin at the crypt base to the villus tip, from where they are shed into the lumen. Cell death in the intestinal epithelium has to be tightly regulated and irregularities might cause pathologies. Excessive cell death has been associated with chronic inflammation as seen in patients with Crohn's disease and ulcerative colitis. While until recently apoptosis was discussed as being essential for epithelial turnover and tissue homeostasis in the intestinal epithelium, recent data using gene deficient mice have challenged this concept. Moreover, an apoptosis-independent mode of programmed cell death, termed necroptosis, has been identified and described in the intestinal epithelium. The following article reviews previous studies on cell death regulation in IEC and a potential role of necroptosis for gut homeostasis. PMID:22689519

  11. Dioscin alleviates dimethylnitrosamine-induced acute liver injury through regulating apoptosis, oxidative stress and inflammation.

    Science.gov (United States)

    Zhang, Weixin; Yin, Lianhong; Tao, Xufeng; Xu, Lina; Zheng, Lingli; Han, Xu; Xu, Youwei; Wang, Changyuan; Peng, Jinyong

    2016-07-01

    In our previous study, the effects of dioscin against alcohol-, carbon tetrachloride- and acetaminophen-induced liver damage have been found. However, the activity of it against dimethylnitrosamine (DMN)-induced acute liver injury remained unknown. In the present study, dioscin markedly decreased serum ALT and AST levels, significantly increased the levels of SOD, GSH-Px, GSH, and decreased the levels of MDA, iNOS and NO. Mechanism study showed that dioscin significantly decreased the expression levels of IL-1β, IL-6, TNF-α, IκBα, p50 and p65 through regulating TLR4/MyD88 pathway to rehabilitate inflammation. In addition, dioscin markedly up-regulated the expression levels of SIRT1, HO-1, NQO1, GST and GCLM through increasing nuclear translocation of Nrf2 against oxidative stress. Furthermore, dioscin significantly decreased the expression levels of FasL, Fas, p53, Bak, Caspase-3/9, and upregulated Bcl-2 level through decreasing IRF9 level against apoptosis. In conclusion, dioscin showed protective effect against DMN-induced acute liver injury via ameliorating apoptosis, oxidative stress and inflammation, which should be developed as a new candidate for the treatment of acute liver injury in the future. PMID:27317992

  12. FLIP the Switch: Regulation of Apoptosis and Necroptosis by cFLIP

    Directory of Open Access Journals (Sweden)

    Yuichi Tsuchiya

    2015-12-01

    Full Text Available cFLIP (cellular FLICE-like inhibitory protein is structurally related to caspase-8 but lacks proteolytic activity due to multiple amino acid substitutions of catalytically important residues. cFLIP protein is evolutionarily conserved and expressed as three functionally different isoforms in humans (cFLIPL, cFLIPS, and cFLIPR. cFLIP controls not only the classical death receptor-mediated extrinsic apoptosis pathway, but also the non-conventional pattern recognition receptor-dependent apoptotic pathway. In addition, cFLIP regulates the formation of the death receptor-independent apoptotic platform named the ripoptosome. Moreover, recent studies have revealed that cFLIP is also involved in a non-apoptotic cell death pathway known as programmed necrosis or necroptosis. These functions of cFLIP are strictly controlled in an isoform-, concentration- and tissue-specific manner, and the ubiquitin-proteasome system plays an important role in regulating the stability of cFLIP. In this review, we summarize the current scientific findings from biochemical analyses, cell biological studies, mathematical modeling, and gene-manipulated mice models to illustrate the critical role of cFLIP as a switch to determine the destiny of cells among survival, apoptosis, and necroptosis.

  13. The X-linked inhibitor of apoptosis regulates long-term depression and learning rate.

    Science.gov (United States)

    Gibon, Julien; Unsain, Nicolas; Gamache, Karine; Thomas, Rhalena A; De Leon, Andres; Johnstone, Aaron; Nader, Karim; Séguéla, Philippe; Barker, Philip A

    2016-09-01

    Hippocampal long-term depression (LTD) is an active form of synaptic plasticity that is necessary for consolidation of spatial memory, contextual fear memory, and novelty acquisition. Recent studies have shown that caspases (CASPs) play an important role in NMDA receptor-dependent LTD and are involved in postsynaptic remodeling and synaptic maturation. In the present study, we examined the role of X-linked inhibitor of apoptosis (XIAP), a putative endogenous CASP inhibitor, in synaptic plasticity in the hippocampus. Analysis in acute brain slices and in cultured hippocampal neurons revealed that XIAP deletion increases CASP-3 activity, enhances α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor internalization, sharply increases LTD, and significantly reduces synapse density. In vivo behaviors related to memory were also altered in XIAP(-/-) mice, with faster acquisition of spatial object location and increased fear memory observed. Together, these results indicate that XIAP plays an important physiologic role in regulating sublethal CASP-3 activity within central neurons and thereby facilitates synaptic plasticity and memory acquisition.-Gibon, J., Unsain, N., Gamache, K., Thomas, R. A., De Leon, A., Johnstone, A., Nader, K., Séguéla, P., Barker, P. A. The X-linked inhibitor of apoptosis regulates long-term depression and learning rate.

  14. Butyrate regulates the expression of inflammatory and chemotactic cytokines in human acute leukemic cells during apoptosis.

    Science.gov (United States)

    Pulliam, Stephanie R; Pellom, Samuel T; Shanker, Anil; Adunyah, Samuel E

    2016-08-01

    Butyrate is a histone deacetylase inhibitor implicated in many studies as a potential therapy for various forms of cancer. High concentrations of butyrate (>1.5mM) have been shown to activate apoptosis in several cancer cell lines including prostate, breast, and leukemia. Butyrate is also known to influence multiple signaling pathways that are mediators of cytokine production. The purpose of this study was to evaluate the impact of high concentrations of butyrate on the cancer microenvironment vis-à-vis apoptosis, cellular migration, and capacity to modulate cytokine expression in cancer cells. The results indicate that high concentrations of butyrate induced a 2-fold activation of caspase-3 and reduced cell viability by 60% in U937 leukemia cells. Within 24h, butyrate significantly decreased the levels of chemokines CCL2 and CCL5 in HL-60 and U937 cells, and decreased CCL5 in THP-1 leukemia cells. Differential effects were observed in treatments with valproic acid for CCL2 and CCL5 indicating butyrate-specificity. Many of the biological effects examined in this study are linked to activation of the AKT and MAPK signaling pathways; therefore, we investigated whether butyrate alters the levels of phosphorylated forms of these signaling proteins and how it correlated with the expression of chemokines. The results show that butyrate may partially regulate CCL5 production via p38 MAPK. The decrease in p-ERK1/2 and p-AKT levels correlated with the decrease in CCL2 production. These data suggest that while promoting apoptosis, butyrate has the potential to influence the cancer microenvironment by inducing differential expression of cytokines. PMID:27253488

  15. Cell proliferation, apoptosis and the related regulators p27, p53 expression in hepatocellular carcinoma

    Institute of Scientific and Technical Information of China (English)

    Zhao Jing; Ke-Jun Nan; Mei-Long Hu

    2005-01-01

    AIM: To investigate the expression of cell apoptosis,proliferation and the related regulators p27, p53 in hepatocellular carcinoma (HCC).METHODS: The expression of p27, p53, proliferating cell nuclear antigen (PCNA) and apoptosis in 47 HCC specimens and 42 surrounding non-cancerous tissues were detected by the immunohistochemistry and terminal deoxy-nudeotidyl transferase-mediated nick end labeling (TUNEL) technique.Meanwhile, the clinical significance of them was analyzed combining with the clinicopathological factors and followup data.RESULTS: (1) The average proliferating index and apoptotic index in HCC were significantly higher than that in adjacent liver tissues. The proliferating index was associated with extrahepatic metastasis. The apoptotic index was significantly lower in TNM stage Ⅰ-Ⅱ than in stage Ⅲ-Ⅳ. The proliferating index of groups with p53-/p27+ was significantly lower than that in group with p53+/p27- (P = 0.030); (2) The level of p27 in the cytoplasmic fraction was higher in non-tumoral liver tissues and was associated with clinical stage; (3) Survival analysis showed advanced stage (P = 0.031) and with extrahepatic metastasis (P = 0.045) was significantly associated with shorter survival. In addition, the prognosis of patients with p53-/p27+ was longer than that of patients with p53+/p27- (P = 0.0356).CONCLUSION: The p53 mutation and decreased p27 expression might be involved in the imbalance of proliferation and apoptosis in HCC. Cytoplasmic displacement might lead to the inactivation of p27 protein in HCC cells and acts early during carcinogenesis of HCC. The combined examination of p27, and p53 expression allows reliable estimation of prognosis for patients with primary hepatic carcinoma.

  16. Up-regulated manganese superoxide dismutase expression increases apoptosis resistance in human esophageal squamous cell carcinomas

    Institute of Scientific and Technical Information of China (English)

    HU Hai; WANG Ming-rong; LUO Man-li; DU Xiao-li; FENG Yan-bin; ZHANG Yu; SHEN Xiao-ming; XU Xin; CAI Yan; HAN Ya-ling

    2007-01-01

    Background Esophageal cancer is one of the most common malignancies in the world.In order to identify the proteins associated with esophageal squamous cell carcinomas(ESCC),we analyzed the protein profiles of ESCC cases with tumor and matched adjacent normal tissues.Methods Two-dimensional electrophoresis(2-DE)was carried out to analyze the protein profiles.Dysregulated protein spots were identified by Matrix-Assisted Laser Desorption Ionization Time-of-Flight(MALDI-TOF)and verified by liquid chromatography/electrospray ionization ion trap-mass spectrometry/mass spectrometry(LC-ESI-IT MS).RT-PCR and immunohistochemistry on tissue microarray were performed to confirm the gene dysregulation in esophageal cancerous tissues.RNA interference (RNAi)was used to knock down the gene expression in ESCC cell lines.Apoptosis assay with annexin V-FITC/PI staining was conducted and cells were analyzed by flow cytometry.Results 2-DE showed that two protein spots with approximate molecular weights and different pl were elevated in 12 out of 18 ESCCs as compared to the corresponding normal tissues.Both the two spots were identified as MnSOD by MALDI-TOF and were verified by LC-ESI-IT MS.MnSOD overexpression was detected in 14 tumors out of 24 cases by RT-PCR and 52 tumors out of 116 cases by immunohistochemistry comparing to normal epithelia.siRNA-mediated silencing of MnSOD in KYSE450 and KYSE150 cell lines revealed that MnSOD protected ESCC cells from apoptosis induced by ultraviolet(UV)and doxorubicin(DOX).Conclusions These findings suggest that there existed two isoforms of MnSOD protein in normal and tumor esophageal tissues.MnSOD was overexpressed in ESCC and its up-regulation in esophageal cancer cells was associated with apoptosis resistance.

  17. Proprotein convertase furin regulates apoptosis and proliferation of granulosa cells in the rat ovary.

    Directory of Open Access Journals (Sweden)

    Xiaokui Yang

    Full Text Available Folliculogenesis is tightly controlled by a series of hormones, growth factors and cytokines, many of which are secreted as proproteins and require processing by proteases before becoming functional. Furin is a member of the subtilisin-like proteases that activate large numbers of proprotein substrates and is ubiquitously expressed and implicated in many physiological and pathological processes. However, the precise role of furin during folliculogenesis has not been thoroughly investigated. The goal of the present work is to identify the role of furin in the development of granulosa cells during folliculogenesis, using immunohistochemistry, RT-PCR, Western blot and functional studies in primary cultured rat granulosa cells. Our results demonstrate that furin is highly expressed in granulosa cells and oocytes of the ovary with very limited expression in other ovarian cells such as the epithelial, stromal or theca cells. Furin siRNA significantly increases apoptosis of the granulosa cells from large antral/preovulatory follicles, in part via downregulation of the anti-apoptotic proteins, XIAP and p-AKT. On the contrary, furin siRNA markedly decreases proliferation of granulosa cells based on the downregulation of proliferation cell nuclear antigen (PCNA. Taken together, these data suggest that furin may play an important role in regulating apoptosis and proliferation of granulosa cells.

  18. TNF-related apoptosis-inducing ligand (TRAIL) as a negative regulator of normal human erythropoiesis.

    Science.gov (United States)

    Zamai, L; Secchiero, P; Pierpaoli, S; Bassini, A; Papa, S; Alnemri, E S; Guidotti, L; Vitale, M; Zauli, G

    2000-06-15

    The impact of tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) on normal hematopoietic development was investigated using adult peripheral blood CD34(+) hematopoietic progenitor cells, induced to differentiate along the erythroid, megakaryocytic, granulocytic, and monocytic lineages by the addition of specific cytokine cocktails. TRAIL selectively reduced the number of erythroblasts, showing intermediate levels of glycophorin A (glycophorin A(interm)) surface expression, which appeared in liquid cultures supplemented with stem cell factor + interleukin 3 + erythropoietin at days 7-10. However, neither immature (day 4) glycophorin A(dim) erythroid cells nor mature (day 14) glycophorin A(bright) erythroblasts were sensitive to TRAIL-mediated apoptosis. Moreover, pre-exposure to TRAIL significantly decreased the number and size of erythroid colonies in semisolid assays. These adverse effects of TRAIL were selective for erythropoiesis, as TRAIL did not significantly influence the survival of cells differentiating along the megakaryocytic, granulocytic, or monocytic lineages. Furthermore, TRAIL was detected by Western blot analysis in lysates obtained from normal bone marrow mononuclear cells. These findings indicate that TRAIL acts in a lineage- and stage of differentiation-specific manner, as a negative regulator of normal erythropoiesis. (Blood. 2000;95:3716-3724) PMID:10845902

  19. Electroacupuncture Ameliorates Cerebral Ischemia-Reperfusion Injury by Regulation of Autophagy and Apoptosis

    Science.gov (United States)

    Shu, Shi; Li, Chun-Ming; You, Yan-Li; Qian, Xiao-Lu

    2016-01-01

    Background. The therapeutic mechanisms of cerebral ischemia treatment by acupuncture are yet not well addressed. Objective. We investigated the effects of electroacupuncture (EA) at GV26 observing the expression of autophagy-related proteins Beclin-1 and LC3B and proportion of apoptotic cells and Bcl-2 positive cells in MCAO/R model rats. Methods. Sprague-Dawley (SD) male rats were randomly assigned to 7 groups: model groups (M6h, M24h, and M72h), EA treatment groups (T6h, T24h, and T72h), and sham operation group (S). Neurological deficit and cerebral infarction volume were measured to assess the improvement effect, while the expression of Beclin-1 and LC3B and proportion of Tunel-positive and Bcl-2 positive cells were examined to explore EA effect on autophagy and apoptosis. Results. EA significantly decreased neurological deficit scores and the volume of cerebral infarction. Beclin-1 was significantly decreased in T24h, while LC3B-II/LC3B-I ratio markedly reduced in 6th hour. EA groups markedly reduced the number of Tunel positive cells, especially in T24h. Meanwhile, the number of Bcl-2 positive cells obviously increased after EA treatment, especially in T6h and T24h. Conclusions. The alleviation of inadequate autophagy and apoptosis may be a key mechanism involved in the reflex regulation of EA at GV26 to treat cerebral ischemia.

  20. Dynamically regulated sumoylation of HDAC2 controls p53 deacetylation and restricts apoptosis following genotoxic stress

    Institute of Scientific and Technical Information of China (English)

    André Brandl; Tobias Wagner; Katharina M. Uhlig; Shirley K. Knauer; Roland H. Stauber; Frauke Melchior; Günter Schneider; Thorsten Heinzel; Oliver H. Kr(a)mer

    2012-01-01

    Histone deacetylase 2 (HDAC2) is relevant for homeostasis and plays a critical role in gastrointestinal cancers.Here,we report that post-translational modification of endogenous HDAC2 with small ubiquitin-related modifier 1 (SUMO1) is a new regulatory switch for the tumor suppressor p53.Sumoylation of HDAC2 at lysine 462 allows binding of HDAC2 to p53.Moreover,sumoylated HDAC2 is a previously not recognized biologically relevant site-specific deacetylase for p53.Deacetylation of p53 at lysine 320 by sumoylated HDAC2 blocks recruitment of p53 into promoter-associated complexes and p53-dependent expression of genes for cell cycle control and apoptosis.Thereby,catalytically active sumoylated HDAC2 restricts p53 functions and attenuates DNA damage-induced apoptosis.Genotoxic stress evokes desumoylation of HDAC2,enabling p53-dependent gene expression,Our data show a new molecular mechanism involving a dynamically controlled HDAC2-sumoylation/p53-acetylation switch that regulates cell fate decisions following genotoxic stress.

  1. Regulation of Caenorhabditis elegans p53/CEP-1-dependent germ cell apoptosis by Ras/MAPK signaling.

    Directory of Open Access Journals (Sweden)

    Rachael Rutkowski

    2011-08-01

    Full Text Available Maintaining genome stability in the germline is thought to be an evolutionarily ancient role of the p53 family. The sole Caenorhabditis elegans p53 family member CEP-1 is required for apoptosis induction in meiotic, late-stage pachytene germ cells in response to DNA damage and meiotic recombination failure. In an unbiased genetic screen for negative regulators of CEP-1, we found that increased activation of the C. elegans ERK orthologue MPK-1, resulting from either loss of the lip-1 phosphatase or activation of let-60 Ras, results in enhanced cep-1-dependent DNA damage induced apoptosis. We further show that MPK-1 is required for DNA damage-induced germ cell apoptosis. We provide evidence that MPK-1 signaling regulates the apoptotic competency of germ cells by restricting CEP-1 protein expression to cells in late pachytene. Restricting CEP-1 expression to cells in late pachytene is thought to ensure that apoptosis doesn't occur in earlier-stage cells where meiotic recombination occurs. MPK-1 signaling regulates CEP-1 expression in part by regulating the levels of GLD-1, a translational repressor of CEP-1, but also via a GLD-1-independent mechanism. In addition, we show that MPK-1 is phosphorylated and activated upon ionising radiation (IR in late pachytene germ cells and that MPK-1-dependent CEP-1 activation may be in part direct, as these two proteins interact in a yeast two-hybrid assay. In summary, we report our novel finding that MAP kinase signaling controls CEP-1-dependent apoptosis by several different pathways that converge on CEP-1. Since apoptosis is also restricted to pachytene stage cells in mammalian germlines, analogous mechanisms regulating p53 family members are likely to be conserved throughout evolution.

  2. Possible mechanism for the regulation of glucose on proliferation, inhibition and apoptosis of colon cancer cells induced by sodium butyrate

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    AIM: To study the effect of glucose on sodium butyrateinduced proliferation inhibition and apoptosis in HT-29 cell line, and explored its possible mechanisms.METHODS: HT-29 cells were grown in RPMI-1640 medium supplemented with 10% fetal calf serum, and were allowed to adhere for 24 h, and then replaced with experimental medium. Cell survival rates were detected by MTT assay. Apoptosis was detected by TUNEL assay. Glucose transport protein 1 (GLUT1) and monocarboxylate transporter 1 (MCT1) mRNA expression was detected by RT-PCR.RESULTS: Low concentration of glucose induced apoptosis and regulated proliferation in HT-29 cell line, and glucose can obviously inhibit the effect of proliferation inhibition and apoptosis induced by sodium butyrate. Glucose also down-regulated the expression of MCT1mRNA (0.28 ± 0.07 vs 0.19 ± 0.10, P < 0.05), and decreased the expression of GLUT1mRNA slightly (0.18 ± 0.04 vs 0.13 ± 0.03, P < 0.05).CONCLUSION: Glucose can regulate the effect of proliferation inhibition and apoptosis induced by sodium butyrate and this influence may be associated with the intracellular concentration of glucose and sodium butyrate.

  3. Quercetin induces apoptosis by activating caspase-3 and regulating Bcl-2 and cyclooxygenase-2 pathways in human HL-60 cells

    Institute of Scientific and Technical Information of China (English)

    Guomin Niu; Songmei Yin; Shuangfeng Xie; Yiqing Li; Danian Nie; Liping Ma; Xiuju Wang; Yudan Wu

    2011-01-01

    Quercetin is one of the naturally occurring dietary flavo-nol compounds. It is present abundantly in plants and has chemopreventive and anticancer effects. To investigate its anticancer mechanism, we examined the activity of quercetin against acute leukemia cell line, HL-60. Our results showed that quercetin inhibited cell proliferation and induced apoptosis in a time- and dose-dependent manner. Furthermore, quercetin down-regulated the expression of anti-apoptosis protein Bcl-2 and up-regulated the expression of pro-apoptosis protein Bax. Caspase-3 was also activated by quercetin, which started a caspase-3-depended mitochodrial pathway to induce apoptosis. It was also found that quercetin inhibited the expression of the cycloocygenase-2 (Cox-2) mRNA and Cox-2 protein. Taken together, these findings suggested that quercetin induces apoptosis in a caspase-3-dependent pathway by inhibiting Cox-2 expression and regulates the expression of downstream apoptotic components, including Bcl-2 and Bax. Quercetin can be a potent and promising medicine which might be safely used in leukemia therapy.

  4. Inhibitors of apoptosis (IAPs) regulate intestinal immunity and inflammatory bowel disease (IBD) inflammation.

    Science.gov (United States)

    Pedersen, Jannie; LaCasse, Eric C; Seidelin, Jakob B; Coskun, Mehmet; Nielsen, Ole H

    2014-11-01

    The inhibitor of apoptosis (IAP) family members, notably cIAP1, cIAP2, and XIAP, are critical and universal regulators of tumor necrosis factor (TNF) mediated survival, inflammatory, and death signaling pathways. Furthermore, IAPs mediate the signaling of nucleotide-binding oligomerization domain (NOD)1/NOD2 and other intracellular NOD-like receptors in response to bacterial pathogens. These pathways are important to the pathogenesis and treatment of inflammatory bowel disease (IBD). Inactivating mutations in the X-chromosome-linked IAP (XIAP) gene causes an immunodeficiency syndrome, X-linked lymphoproliferative disease type 2 (XLP2), in which 20% of patients develop severe intestinal inflammation. In addition, 4% of males with early-onset IBD also have inactivating mutations in XIAP. Therefore, the IAPs play a greater role in gut homeostasis, immunity and IBD development than previously suspected, and may have therapeutic potential.

  5. RPS27a promotes proliferation, regulates cell cycle progression and inhibits apoptosis of leukemia cells

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Houcai; Yu, Jing; Zhang, Lixia; Xiong, Yuanyuan; Chen, Shuying; Xing, Haiyan; Tian, Zheng; Tang, Kejing; Wei, Hui; Rao, Qing; Wang, Min; Wang, Jianxiang, E-mail: wangjx@ihcams.ac.cn

    2014-04-18

    Highlights: • RPS27a expression was up-regulated in advanced-phase CML and AL patients. • RPS27a knockdown changed biological property of K562 and K562/G01 cells. • RPS27a knockdown affected Raf/MEK/ERK, P21 and BCL-2 signaling pathways. • RPS27a knockdown may be applicable for new combination therapy in CML patients. - Abstract: Ribosomal protein S27a (RPS27a) could perform extra-ribosomal functions besides imparting a role in ribosome biogenesis and post-translational modifications of proteins. The high expression level of RPS27a was reported in solid tumors, and we found that the expression level of RPS27a was up-regulated in advanced-phase chronic myeloid leukemia (CML) and acute leukemia (AL) patients. In this study, we explored the function of RPS27a in leukemia cells by using CML cell line K562 cells and its imatinib resistant cell line K562/G01 cells. It was observed that the expression level of RPS27a was high in K562 cells and even higher in K562/G01 cells. Further analysis revealed that RPS27a knockdown by shRNA in both K562 and K562G01 cells inhibited the cell viability, induced cell cycle arrest at S and G2/M phases and increased cell apoptosis induced by imatinib. Combination of shRNA with imatinib treatment could lead to more cleaved PARP and cleaved caspase-3 expression in RPS27a knockdown cells. Further, it was found that phospho-ERK(p-ERK) and BCL-2 were down-regulated and P21 up-regulated in RPS27a knockdown cells. In conclusion, RPS27a promotes proliferation, regulates cell cycle progression and inhibits apoptosis of leukemia cells. It appears that drugs targeting RPS27a combining with tyrosine kinase inhibitor (TKI) might represent a novel therapy strategy in TKI resistant CML patients.

  6. Up-regulation of podoplanin involves in neuronal apoptosis in LPS-induced neuroinflammation.

    Science.gov (United States)

    Song, Yan; Shen, Jianhong; Lin, Yuchang; Shen, Jiabing; Wu, Xinming; Yan, Yaohua; Zhou, Li; Zhang, Haiyan; Zhou, Ying; Cao, Maohong; Liu, Yonghua

    2014-08-01

    Podoplanin (PDPN) is a mucin-type transmembrane sialoglycoprotein expressed in multiple tissues in adult animals, including the brain, lungs, kidney, and lymphoid organs. Studies of this molecule have demonstrated its great importance in tumor metastasis, platelet aggregation, and lymphatic vessel formation. However, information regarding its regulation and possible function in the central nervous system is still limited. In this study, we performed a neuroinflammatory model by lipopolysaccharide (LPS) lateral ventral injection in adult rats and detected increased expression of PDPN in the brain cortex. Immunofluorescence indicated that PDPN was located in the neurons, but not astrocytes. Moreover, there was a concomitant up-regulation of active caspase-3, cyclin D1, and CDK4 in vivo and vitro studies. In addition, the expression of these three proteins in cortical primary neurons was decreased after knocking down PDPN by siRNA. Collectively, all these results suggested that the up-regulation of PDPN might be involved in neuronal apoptosis in neuroinflammation after LPS injection. PMID:24821010

  7. The Effect of Growth Hormone Administration on the Regulation of Mitochondrial Apoptosis in-Vivo

    Directory of Open Access Journals (Sweden)

    James Keane

    2015-06-01

    Full Text Available The purpose of this study was to determine whether recombinant human growth hormone (rhGH would show any significant effects on the expression of apoptosis regulating proteins in peripheral blood mononuclear cells (PBMCs. Additionally, the potential for post-transcriptional regulation of gene expression by miRNA was assessed in two cellular compartments, the cytosol and the mitochondria. Ten male subjects were subcutaneously injected with either rhGH (1 mg or saline (0.9% for seven consecutive days in a double-blinded fashion. Blood sampling was undertaken prior to treatment administration and over a period of three weeks following treatment cessation. Bcl-2 and Bak gene and protein expression levels were measured in PBMCs, while attention was also directed to the expression of miR-181a and miR-125b, known translational inhibitors of Bcl-2 and Bak respectively. Results showed that rhGH significantly decreased Bak protein concentrations compared to placebo samples for up to 8 days post treatment. While cytosolic miRNA expression was not found to be significantly affected by rhGH, measurement of the expression of miR-125b in mitochondrial fractions showed a significant down-regulation eight days post-rhGH administration. These findings suggest that rhGH induces short-term anti-apoptotic effects which may be partially mediated through a novel pathway that alters the concentration of mitochondrially-associated miRNAs.

  8. Blockade of the BAK hydrophobic groove by inhibitory phosphorylation regulates commitment to apoptosis.

    Directory of Open Access Journals (Sweden)

    Abul Azad

    Full Text Available The BCL-2 family protein BAK is a key regulator of mitochondrial apoptosis. BAK activation first involves N-terminal conformational changes that lead to the transient exposure of the BAK BH3 domain that then inserts into a hydrophobic groove on another BAK molecule to form symmetric dimers. We showed recently that post-translational modifications are important in the regulation of BAK conformational change and multimerization, with dephosphorylation at tyrosine 108 constituting an initial step in the BAK activation process. We now show that dephosphorylation of serine 117 (S117, located in the BAK hydrophobic groove, is also critical for BAK activation to proceed to completion. Phosphorylation of BAK at S117 has two important regulatory functions: first, it occludes the binding of BH3-containing peptides that bind to BAK causing activation and cytochrome c release from mitochondria; second, it prevents BAK-BH3:BAK-Groove interactions that nucleate dimer formation for subsequent multimerization. Hence, BH3-mediated BAK conformational change and subsequent BAK multimerization for cytochrome c release and cell death is intimately linked to, and dependent on, dephosphorylation at S117. Our study reveals important novel mechanistic and structural insights into the temporal sequence of events governing the process of BAK activation in commitment to cell death and how they are regulated.

  9. Berberine Induces Apoptosis in p53-Null Leukemia Cells by Down-Regulating XIAP at the Post-Transcriptional Level

    Directory of Open Access Journals (Sweden)

    Jian Liu

    2013-11-01

    Full Text Available Background: Berberine exerts anticancer activities both in vitro and in vivo through different mechanisms. However, the underlying molecular mechanisms of berberine induced p53-independent apoptosis remain unclear. Methods: The p53-null leukemia cell line EU-4 cells were exposed to berberine. Then the cell viability and apoptosis were determined. Western blot and PCR were employed to detect the expression of apoptosis related protein, XIAP and MDM2. Small interfering RNA (siRNA was applied to knock down endogenous expression of MDM2 and XIAP. Results: Berberine induced p53-independent, XIAP-mediated apoptotic cell death in p53-null leukemia cells. Treatment with berberine resulted in suppression of XIAP protein in a dose- and time- dependent manner. Berberine induced down-regulation of XIAP protein involving inhibition of MDM2 expression and a proteasome-dependent pathway. Moreover, inhibition of XIAP by berberine or siRNA increased the sensitivity of leukemia cells to doxorubicin-induced apoptosis. Conclusion: Our findings characterize the molecular mechanisms of berberine-induced caspase activation and subsequent apoptosis, and berberine may be a novel candidate inducer of apoptosis in leukemia cells, which normally lack p53 expression.

  10. Identification of genes regulated by Wnt/β-catenin pathway and involved in apoptosis via microarray analysis

    International Nuclear Information System (INIS)

    Wnt/β-catenin pathway has critical roles in development and oncogenesis. Although significant progress has been made in understanding the downstream signaling cascade of this pathway, little is known regarding Wnt/β-catenin pathway modification of the cellular apoptosis. To identify potential genes regulated by Wnt/β-catenin pathway and involved in apoptosis, we used a stably integrated, inducible RNA interference (RNAi) vector to specific inhibit the expression and the transcriptional activity of β-catenin in HeLa cells. Meanwhile, we designed an oligonucleotide microarray covering 1384 apoptosis-related genes. Using oligonucleotide microarrays, a series of differential expression of genes was identified and further confirmed by RT-PCR. Stably integrated inducible RNAi vector could effectively suppress β-catenin expression and the transcriptional activity of β-catenin/TCF. Meanwhile, depletion of β-catenin in this manner made the cells more sensitive to apoptosis. 130 genes involved in some important cell-apoptotic pathways, such as PTEN-PI3K-AKT pathway, NF-κB pathway and p53 pathway, showed significant alteration in their expression level after the knockdown of β-catenin. Coupling RNAi knockdown with microarray and RT-PCR analyses proves to be a versatile strategy for identifying genes regulated by Wnt/β-catenin pathway and for a better understanding the role of this pathway in apoptosis. Some of the identified β-catenin/TCF directed or indirected target genes may represent excellent targets to limit tumor growth

  11. MiR-21 up-regulation mediates glioblastoma cancer stem cells apoptosis and proliferation by targeting FASLG.

    Science.gov (United States)

    Shang, Chao; Guo, Yan; Hong, Yang; Liu, Yun-hui; Xue, Yi-xue

    2015-03-01

    To investigate whether miR-21 can affect the apoptosis and proliferation of glioblastoma cancer stem cells (GSCs) from down-regulating FASLG. The expression of miRNA-21 was detected by quantitative real-time PCR in normal brain tissue and glioblastoma samples, and the changes of miRNA-21 expression between GSCs and non-GSCs were also detected. The apoptosis and proliferation ability of miR-21 in GSCs were analyzed by MTT and flow cytometry assay after anti-miR-21 transfection. For the regulation mechanism analysis of miR-21, TargetScan, PicTar and microRNA were selected to predict some potential target genes of miR-21. The predicted gene was identified to be the direct and specific target gene of miR-21 by luciferase activities assay and western blot. RNA interference technology was used to confirm the apoptosis and proliferation effects of miR-21 were directly induced by FASLG. The expression of miR-21 increased significantly in glioblastoma contrast to normal brain tissue, and miR-21 up-regulated in GSCs remarkably. The proliferation of GSCs cell could be inhibited with high-expression of miR-21 and this effect could be restored by miR-21 knocked down. Mechanism analysis revealed that FASLG was a specific and direct target gene of miR-21. The advanced effects of anti-miR-21 on GSCs apoptosis and proliferation were mediated by expression of silenced FASLG. In summary, aberrantly expressed miR-21 regulates GSCs apoptosis and proliferation partly through directly down-regulating FASLG protein expression in GSCs and this might offer a new potential therapeutic stratagem for glioblastoma. PMID:25394756

  12. Combined analysis of cell growth and apoptosis-regulating proteins in HPVs associated anogenital tumors

    International Nuclear Information System (INIS)

    The clinical course of human papillomavirus (HPV) associated with Bowenoid papulosis and condyloma acuminatum of anogenital tumors are still unknown. Here we evaluated molecules that are relevant to cellular proliferation and regulation of apoptosis in HPV associated anogenital tumors. We investigated the levels of telomerase activity, and inhibitor of apoptosis proteins (IAPs) family (c-IAP1, c-IAP2, XIAP) and c-Myc mRNA expression levels in 20 specimens of Bowenoid papulosis and 36 specimens of condyloma acuminatum in anogenital areas. Overall, phosphorylated (p-) AKT, p-ribosomal protein S6 (S6) and p-4E-binding protein 1 (4EBP1) expression levels were examined by immunohistochemistry in anogenital tumors both with and without positive telomerase activity. Positive telomerase activity was detected in 41.7% of Bowenoid papulosis and 27.3% of condyloma acuminatum compared to normal skin (p < 0.001). In contrast, the expression levels of Bowenoid papulosis indicated that c-IAP1, c-IAP2 and XIAP mRNA were significantly upregulated compared to those in both condyloma acuminatum samples (p < 0.001, p < 0.001, p = 0.022, respectively) and normal skin (p < 0.001, p = 0.002, p = 0.034, respectively). Overall, 30% of Bowenoid papulosis with high risk HPV strongly promoted IAPs family and c-Myc but condyloma acuminatum did not significantly activate those genes. Immunohistochemically, p-Akt and p-S6 expressions were associated with positive telomerase activity but not with p-4EBP1 expression. Combined analysis of the IAPs family, c-Myc mRNA expression, telomerase activity levels and p-Akt/p-S6 expressions may provide clinically relevant molecular markers in HPV associated anogenital tumors

  13. EFFECT OF UP-REGULATION OF S-ADOMET SYNTHETASE ON TAXOL-INDUCED APOPTOSIS IN HUMAN BREAST CANCER CELLS

    Institute of Scientific and Technical Information of China (English)

    Chen Lirong; Zheng Shu; Fan Weimin; Zhang Suzhan

    1998-01-01

    Objective:To investigate the gene regulation of taxolinduced apoptosis. Methods: Northern blot hybridization,enzyme activity assay of S-AdoMet synthetase and flow cytometry were performed in the investigation of expression in the Mrna level and biological action of SAdoMet synthetase in taxol-induced apoptosis in human breast cancer cell line (Bcap 37). Results: Up-regulation of S-AdoMet synthetase expression was resulted by taxol treatment and the expression peaked at 48hours. Moreover,the up-regulation of S-AdoMet synthetase was associated with cytotoxicity of antimicrotubule agents including taxol and colchicine.Inhibition rate of S-AdoMet synthetase activity by 1%DMSO was 34% in taxol-treated cells and 14% in taxoluntreated cells compared to control groups, respectively.Posttreatment with 1% DMSO following pretreatment with individual antitumor agent for 3 hrs promoted apoptotic cell death of taxol-,colchicine-,and adriamycintreated Bcap37 cells. Conclusion : The induction of apoptosis enhanced by post-treatment with DMSO in taxol-treated cells is probably linked to its inhibition on enzyme activity of S-AdoMet synthetase ,suggesting that the increased expression of S-AdoMet synthetase possibly plays an important role in protecting cells from DNA fragmentation in taxol-induced apoptosis.

  14. MicroRNA-221/222 regulate ox-LDL-induced endothelial apoptosis via Ets-1/p21 inhibition.

    Science.gov (United States)

    Qin, Bing; Cao, Yuze; Yang, Huan; Xiao, Bo; Lu, Zhengqi

    2015-07-01

    Endothelial cells (ECs) apoptosis induced by oxidized low-density lipoprotein (ox-LDL) is thought to play an essential role in atherosclerosis. MicroRNAs (miRNAs) are a class of short non-coding RNAs, acting as posttranscriptional regulators of protein-coding genes involved in vascular cell biology. MiRNA-221 and miRNA-222 (miR-221/222) are known to be involved in the regulation of endothelial inflammation and angiogenesis. However, the function of miR-221/222 in ox-LDL-induced ECs apoptosis and atherosclerosis is still unknown. Here, we showed that miR-221/222 expression was markedly down-regulated in ox-LDL-induced apoptotic human umbilical cord vein endothelial cells. MiR-221/222 inhibition enhanced apoptosis in ECs, whereas over-expression of miR-221/222 could partly alleviate apoptotic cell death mediated by ox-LDL through suppression of Ets-1 and its downstream target p21. These findings suggest that manipulation of the miR-221/222-Ets-1-p21 pathway may offer a novel strategy for treatment of endothelial apoptosis and atherosclerosis.

  15. Autophagy counteracts apoptosis in human multiple myeloma cells exposed to oridonin in vitro via regulating intracellular ROS and SIRT1

    Institute of Scientific and Technical Information of China (English)

    Rong ZENG; Yan CHEN; Shuai ZHAO; Guo-hui CUI

    2012-01-01

    To explore the mechanisms underlying the oridonin-induced apoptosis and autophagy in human multiple myeloma cells in vitro.Methods:Human multiple myeloma RPMI8266 cells were used.The cell viability was assessed using MTT assay.Morphological changes of apoptosis and autophagy were observed under transmission electron microscope.TUNEL and annexin V-FITC/PI dual staining assays were used to measure apoptosis.Autophagy was analyzed using Western blot analysis and immunofluorescence staining with a QDs605 nm-Anti-LC3 fluorescent probe.Intracellular ROS was estimated with flow cytometry using DCFH-DA fluorescent probe.Protein levels of active caspase 3,Beclin 1 and SIRT1 were determined with Western blot analysis.Results:Exposure to oridonin (1-64 μmol/L) inhibited the proliferation of RPMI8266 cells in a concentration-dependent manner with an IC50 value of 6.74 μmol/L.Exposure to oridonin (7 μmol/L) simultaneously induced caspase 3-mediated apoptosis and Beclin 1-dependent autophagy of RPMI8266 cells.Both the apoptosis and autophagy were time-dependent,and apoptosis was the main effector pathway of cell death.Exposure to oridonin (7 μmol/L) increased intracellular ROS and reduced SIRT1 nuclear protein in a time-dependent manner.The blockade of intracellular generation of ROS by NAC (5 mmol/L) abrogated apoptosis,autophagy and the decrease of SIRT1 in the cells exposed to oridonin (7 μmol/L).The inhibition of autophagy by 3-MA (5 mmol/L) sensitized the cells to oridonin-induced apoptosis,which was accompanied by increased intracellular ROS and decreased SlRT1.Conclusion:Oridonin simultaneously induces apoptosis and autophagy of human multiple myeloma RPMI8266 cells via regulation of intracellular ROS generation and SIRT1 nuclear protein.The cytotoxicity of oridonin is mainly mediated through the apoptotic pathway,whereas the autophagy protects the cells from apoptosis.

  16. Roles and regulation of autophagy and apoptosis in the remodelling of the lepidopteran midgut epithelium during metamorphosis

    Science.gov (United States)

    Romanelli, Davide; Casartelli, Morena; Cappellozza, Silvia; de Eguileor, Magda; Tettamanti, Gianluca

    2016-01-01

    We previously showed that autophagy and apoptosis occur in the removal of the lepidopteran larval midgut during metamorphosis. However, their roles in this context and the molecular pathways underlying their activation and regulation were only hypothesized. The results of the present study better clarify the timing of the activation of these two processes: autophagic and apoptotic genes are transcribed at the beginning of metamorphosis, but apoptosis intervenes after autophagy. To investigate the mechanisms that promote the activation of autophagy and apoptosis, we designed a set of experiments based on injections of 20-hydroxyecdysone (20E). Our data demonstrate that autophagy is induced at the end of the last larval stage by the 20E commitment peak, while the onset of apoptosis occurs concomitantly with the 20E metamorphic peak. By impairing autophagic flux, the midgut epithelium degenerated faster, and higher caspase activity was observed compared to controls, whereas inhibiting caspase activation caused a severe delay in epithelial degeneration. Our data demonstrate that autophagy plays a pro-survival function in the silkworm midgut during metamorphosis, while apoptosis is the major process that drives the demise of the epithelium. The evidence collected in this study seems to exclude the occurrence of autophagic cell death in this setting. PMID:27609527

  17. Capsaicin sensitizes TRAIL-induced apoptosis through Sp1-mediated DR5 up-regulation: Involvement of Ca2+ influx

    International Nuclear Information System (INIS)

    Although tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) induces apoptosis in various malignant cells, several cancers including human hepatocellular carcinoma (HCC) exhibit potent resistance to TRAIL-induced cell death. The aim of this study is to evaluate the anti-cancer potential of capsaicin in TRAIL-induced cancer cell death. As indicated by assays that measure phosphatidylserine exposure, mitochondrial activity and activation of caspases, capsaicin potentiated TRAIL-resistant cells to lead to cell death. In addition, we found that capsaicin induces the cell surface expression of TRAIL receptor DR5, but not DR4 through the activation Sp1 on its promoter region. Furthermore, we investigated that capsaicin-induced DR5 expression and apoptosis are inhibited by calcium chelator or inhibitors for calmodulin-dependent protein kinase. Taken together, our data suggest that capsaicin sensitizes TRAIL-mediated HCC cell apoptosis by DR5 up-regulation via calcium influx-dependent Sp1 activation. Highlights: ► Capsaicin sensitizes TRAIL-induced apoptosis through activation of caspases. ► Capsaicin induces expression of DR5 through Sp1 activation. ► Capsaicin activates calcium signaling pathway.

  18. lncRNA H19/miR-675 axis regulates cardiomyocyte apoptosis by targeting VDAC1 in diabetic cardiomyopathy

    Science.gov (United States)

    Li, Xiangquan; Wang, Hao; Yao, Biao; Xu, Weiting; Chen, Jianchang; Zhou, Xiang

    2016-01-01

    We previously established a rat model of diabetic cardiomyopathy (DCM) and found that the expression of lncRNA H19 was significantly downregulated. The present study was designed to investigate the pathogenic role of H19 in the development of DCM. Overexpression of H19 in diabetic rats attenuated oxidative stress, inflammation and apoptosis, and consequently improved left ventricular function. High glucose was associated with reduced H19 expression and increased cardiomyocyte apoptosis. To explore the molecular mechanisms involved, we performed in vitro experiments using cultured neonatal rat cardiomyocytes. Our results showed that miR-675 expression was decreased in cardiomyocytes transfected with H19 siRNA. The 3′UTR of VDAC1 was cloned downstream of a luciferase reporter construct and cotransfected into HEK293 cells with miR-675 mimic. The results of luciferase assay indicated that VDAC1 might be a direct target of miR-675. The expression of VDAC1 was upregulated in cardiomyocytes transfected with miR-675 antagomir, which consequently promotes cellular apoptosis. Moreover, enforced expression of H19 was found to reduce VDAC1 expression and inhibit apoptosis in cardiomyocytes exposed to high glucose. In conclusion, our study demonstrates that H19/miR-675 axis is involved in the regulation of high glucose-induced apoptosis by targeting VDAC1, which may provide a novel therapeutic strategy for the treatment of DCM. PMID:27796346

  19. Roles and regulation of autophagy and apoptosis in the remodelling of the lepidopteran midgut epithelium during metamorphosis

    Science.gov (United States)

    Romanelli, Davide; Casartelli, Morena; Cappellozza, Silvia; de Eguileor, Magda; Tettamanti, Gianluca

    2016-09-01

    We previously showed that autophagy and apoptosis occur in the removal of the lepidopteran larval midgut during metamorphosis. However, their roles in this context and the molecular pathways underlying their activation and regulation were only hypothesized. The results of the present study better clarify the timing of the activation of these two processes: autophagic and apoptotic genes are transcribed at the beginning of metamorphosis, but apoptosis intervenes after autophagy. To investigate the mechanisms that promote the activation of autophagy and apoptosis, we designed a set of experiments based on injections of 20-hydroxyecdysone (20E). Our data demonstrate that autophagy is induced at the end of the last larval stage by the 20E commitment peak, while the onset of apoptosis occurs concomitantly with the 20E metamorphic peak. By impairing autophagic flux, the midgut epithelium degenerated faster, and higher caspase activity was observed compared to controls, whereas inhibiting caspase activation caused a severe delay in epithelial degeneration. Our data demonstrate that autophagy plays a pro-survival function in the silkworm midgut during metamorphosis, while apoptosis is the major process that drives the demise of the epithelium. The evidence collected in this study seems to exclude the occurrence of autophagic cell death in this setting.

  20. Experimental study of atorvastatin regulation of HL-60 leukemia cell apoptosis through PI3K/AKT/mTOR

    Institute of Scientific and Technical Information of China (English)

    Lin Mei

    2016-01-01

    Objective:To study the regulatory effect of atorvastatin on HL-60 leukemia cell apoptosis through PI3K/AKT/mTOR. Methods:HL-60 leukemia cells were cultured and processed with different doses of atorvastatin, and then cell apoptosis as well as PI3K, AKT and mTOR expression levels were detected;cells were processed with PI3K, AKT and mTOR inhibitors Wortmannin, Perifosine and Rapamycin, and then cell apoptosis was detected. Results:Different doses of atorvastatin processing could increase the numbers of early apoptotic cells and apoptotic-like necrotic cells, and decrease mRNA contents of PI3K, AKT and mTOR in dose-dependent and time-dependent manner;PI3K, AKT and mTOR inhibitors Wortmannin, Perifosine and Rapamycin processing could increase the numbers of early apoptotic cells and apoptotic-like necrotic cells, and up-regulate the expression of apoptosis genes FasL, Bax, Caspase-3 and Caspase-9. Conclusion:Atorvastatin can induce HL-60 leukemia cell apoptosis through inhibiting PI3K/AKT/mTOR signaling pathway.

  1. Inhibition of Corydalis decumbens Alkaloids on Hydrogen Peroxideinduced Apoptosis of PC12 Cells through Down-regulating Caspase-3 Expression

    Institute of Scientific and Technical Information of China (English)

    YAN Ren-jie; YANG Yi-fang; LUO Yong-ming; WU Chun-zhen

    2011-01-01

    Objective To extract alkaloids from Corydalis decumbens (AsCD) by supercritical CO2 fluid extraction (SFE) and to evaluate protective effects of AsCD against hydrogen peroxide (H2O2)-induced apoptosis in rat PC12 cells.Methods AsCD were extracted by SFE and oxidative damage PC12 cells model was induced by H2O2.The survival rate of the cells was determined by MTT assay; Lactate dehydrogenase release was determined by ultraviolet spectrophotometry; Flow cytometry was used to detect apoptosis; Caspase-3 mRNA and protein were determined by real-time PCR and Western blotting assay,respectively.Results AsCD remarkably reduced the cytotoxicity,prevented membrane damage,and inhibited cell apoptosis.AsCD inhibited Caspase-3 mRNA and protein expression induced by H2O2 in PC12 cells.Conclusion AsCD possess protective effects against H2O2-induced apoptosis in PC12 cells,and the mechanism of AsCD responsible to the inhibition of apoptosis is possibly attributed to thedown-regulating Caspase-3 expression.AsCD might be useful in the treatment of oxidative stress-related neurodegenerative diseases.

  2. Monocytes regulate the mechanism of T-cell death by inducing Fas-mediated apoptosis during bacterial infection.

    Directory of Open Access Journals (Sweden)

    Marc Daigneault

    Full Text Available Monocytes and T-cells are critical to the host response to acute bacterial infection but monocytes are primarily viewed as amplifying the inflammatory signal. The mechanisms of cell death regulating T-cell numbers at sites of infection are incompletely characterized. T-cell death in cultures of peripheral blood mononuclear cells (PBMC showed 'classic' features of apoptosis following exposure to pneumococci. Conversely, purified CD3(+ T-cells cultured with pneumococci demonstrated necrosis with membrane permeabilization. The death of purified CD3(+ T-cells was not inhibited by necrostatin, but required the bacterial toxin pneumolysin. Apoptosis of CD3(+ T-cells in PBMC cultures required 'classical' CD14(+ monocytes, which enhanced T-cell activation. CD3(+ T-cell death was enhanced in HIV-seropositive individuals. Monocyte-mediated CD3(+ T-cell apoptotic death was Fas-dependent both in vitro and in vivo. In the early stages of the T-cell dependent host response to pneumococci reduced Fas ligand mediated T-cell apoptosis was associated with decreased bacterial clearance in the lung and increased bacteremia. In summary monocytes converted pathogen-associated necrosis into Fas-dependent apoptosis and regulated levels of activated T-cells at sites of acute bacterial infection. These changes were associated with enhanced bacterial clearance in the lung and reduced levels of invasive pneumococcal disease.

  3. Down-regulation of survivin expression by small interfering RNA induces pancreatic cancer cell apoptosis and enhances its radiosensitivity

    Institute of Scientific and Technical Information of China (English)

    Hai-Tao Guan; Xing-Huan Xue; Zhi-Jun Dai; Xi-Jing Wang; Ang Li; Zhao-Yin Qin

    2006-01-01

    AIM: To investigate the inhibitory effect of small interfering RNA (siRNA) on the expression of survivin in pancreatic cancer cell line PC-2 and the role of siRNA in inducing PC-2 cell apoptosis and enhancing its radiosensitivity.METHODS: A siRNA plasmid expression vector against survivin was constructed and transfected into PC-2 cells with LipofectamineTM 2000. The down regulation of survivin expression was detected by semi-quantitive RT-PCR and immunohistochemical SP method and the role of siRNA in inducing PC-2 cell apoptosis and enhancing its radiosensitivity was detected by flow cytometry.RESULTS: The sequence-specific siRNA efficiently and specifically down-regulated the expression of survivin at both mRNA and protein levels. The expression inhibition ratio was 81.25% at mRNA level detected by semiquantitive RT-PCR and 74.24% at protein level detected by immunohistochemical method. Forty-eight hours after transfection,apoptosis was induced in 7.03% cells by siRNA and in 14.58% cells by siRNA combined with radiation.CONCLUSION: The siRNA plasmid expression vector against survivin can inhibit the expression of survivin in PC-2 cells efficiently and specifically. Inhibiting the expression of survivin can induce apoptosis of PC-2 cells and enhance its radiosensitivity significantly. RNAi against survivin is of potential value in gene tnerapy of pancreatic cancer.

  4. A Conserved Myc Protein Domain, MBIV, Regulates DNA Binding, Apoptosis, Transformation, and G2 Arrest†

    Science.gov (United States)

    Cowling, Victoria H.; Chandriani, Sanjay; Whitfield, Michael L.; Cole, Michael D.

    2006-01-01

    The myc family of oncogenes is well conserved throughout evolution. Here we present the characterization of a domain conserved in c-, N-, and L-Myc from fish to humans, N-Myc317-337, designated Myc box IV (MBIV). A deletion of this domain leads to a defect in Myc-induced apoptosis and in some transformation assays but not in cell proliferation. Unlike other Myc mutants, MycΔMBIV is not a simple loss-of-function mutant because it is hyperactive for G2 arrest in primary cells. Microarray analysis of genes regulated by N-MycΔMBIV reveals that it is weakened for transactivation and repression but not nearly as defective as N-MycΔMBII. Although the mutated region is not part of the previously defined DNA binding domain, we find that N-MycΔMBIV has a significantly lower affinity for DNA than the wild-type protein in vitro. Furthermore, chromatin immunoprecipitation shows reduced binding of N-MycΔMBIV to some target genes in vivo, which correlates with the defect in transactivation. Thus, this conserved domain has an unexpected role in Myc DNA binding activity. These data also provide a novel separation of Myc functions linked to the modulation of DNA binding activity. PMID:16705173

  5. 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.

  6. Acteoside-mediates chemoprevention of experimental liver carcinogenesis through STAT-3 regulated oxidative stress and apoptosis.

    Science.gov (United States)

    Peerzada, Kaiser J; Faridi, Aamir H; Sharma, Love; Bhardwaj, Subhash C; Satti, Naresh K; Shashi, Bhushan; Tasduq, Sheikh A

    2016-07-01

    In the absence of an effective therapy against Hepatocellular Carcinoma (HCC), chemoprevention remains an important strategy to circumvent morbidity and mortality. Here, we examined chemopreventive potential of Acteoside (ACT), a plant derived phenylethanoid glycoside against an environmental and dietary carcinogen, diethylnitrosamine (DEN)-induced rat hepatocarcinogenesis. ACT treatment (0.1 and 0.3% supplemented with diet) started 2 weeks before DEN challenge and continued for 18 weeks thereafter, showed a remarkable chemopreventive activity. ACT treatment resulted in reduced HCC nodules. Histopathology showed progressive tissue damage, necrosis (5 weeks), hepatocytic injury (10 weeks), anisonucleosis with presence of prominent nucleoli, sinusidal dilations, and lymphomono nuclear inflammation (18 weeks). Biochemical analysis showed hepatocytic injury (raised ALT, p reactive oxygen species (ROS) levels and prevented mitochondrial membrane potential (MMP) loss. Immunoblotting showed ACT treatment reversed DEN-induced NF-κB, Bax, Cytochrome C, Bcl-2, and Stat-3 levels. We conclude that chemoprotective effect of ACT is mediated by STAT-3 dependent regulation of oxidative stress and apoptosis and ACT has potential to be developed as a chemopreventive agent. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 782-798, 2016. PMID:26990576

  7. Apoptosis in haematological cancer : regulation by mitochondria, the BCL-2 family and IAPs

    NARCIS (Netherlands)

    Graaf, Aniek Odorica de

    2006-01-01

    This thesis describes a number of studies that investigated several aspects of apoptosis in lymphoid malignancies. Resistance to apoptosis is an important asset of cancer cells, which allows them to evade cell death signals instigated by the changes they undergo during transformation, such as genet

  8. E2F1-Mediated Induction of NFYB Attenuates Apoptosis via Joint Regulation of a Pro-Survival Transcriptional Program.

    Directory of Open Access Journals (Sweden)

    Xiaolei Jiang

    Full Text Available The E2F1 transcription factor regulates cell proliferation and apoptosis through the control of a considerable variety of target genes. Previous work has detailed the role of other transcription factors in mediating the specificity of E2F function. Here we identify the NF-YB transcription factor as a novel direct E2F1 target. Genome-wide expression analysis of the effects of NFYB knockdown on E2F1-mediated transcription identified a large group of genes that are co-regulated by E2F1 and NFYB. We also provide evidence that knockdown of NFYB enhances E2F1-induced apoptosis, suggesting a pro-survival function of the NFYB/E2F1 joint transcriptional program. Bioinformatic analysis suggests that deregulation of these NFY-dependent E2F1 target genes might play a role in sarcomagenesis as well as drug resistance.

  9. Regulating Cell Apoptosis on Layer-by-Layer Assembled Multilayers of Photosensitizer-Coupled Polypeptides and Gold Nanoparticles

    Science.gov (United States)

    Xing, Ruirui; Jiao, Tifeng; Ma, Kai; Ma, Guanghui; Möhwald, Helmuth; Yan, Xuehai

    2016-01-01

    The design of advanced, nanostructured materials by layer-by-layer (LbL) assembly at the molecular level is of great interest because of the broad application of these materials in the biomedical field especially in regulating cell growth, adhesion, movement, differentiation and detachment. Here, we fabricated functional hybrid multilayer films by LbL assembly of biocompatible photosensitizer-coupled polypeptides and collagen-capped gold nanoparticles. The resulting multilayer film can well accommodate cells for adhesion, growth and proliferation. Most significantly, controlled cell apoptosis (detachment) and patterning of the multilayer film is achieved by a photochemical process yielding reactive oxygen species (ROS). Moreover, the site and shape of apoptotic cells can be controlled easily by adjusting the location and shape of the laser beam. The LbL assembled multilayer film with integration of functions provides an efficient platform for regulating cell growth and apoptosis (detachment). PMID:27211344

  10. Regulating Cell Apoptosis on Layer-by-Layer Assembled Multilayers of Photosensitizer-Coupled Polypeptides and Gold Nanoparticles

    Science.gov (United States)

    Xing, Ruirui; Jiao, Tifeng; Ma, Kai; Ma, Guanghui; Möhwald, Helmuth; Yan, Xuehai

    2016-05-01

    The design of advanced, nanostructured materials by layer-by-layer (LbL) assembly at the molecular level is of great interest because of the broad application of these materials in the biomedical field especially in regulating cell growth, adhesion, movement, differentiation and detachment. Here, we fabricated functional hybrid multilayer films by LbL assembly of biocompatible photosensitizer-coupled polypeptides and collagen-capped gold nanoparticles. The resulting multilayer film can well accommodate cells for adhesion, growth and proliferation. Most significantly, controlled cell apoptosis (detachment) and patterning of the multilayer film is achieved by a photochemical process yielding reactive oxygen species (ROS). Moreover, the site and shape of apoptotic cells can be controlled easily by adjusting the location and shape of the laser beam. The LbL assembled multilayer film with integration of functions provides an efficient platform for regulating cell growth and apoptosis (detachment).

  11. THE HEPARIN-BINDING DOMAIN AND V REGION OF FIBRONECTIN REGULATE APOPTOSIS BY SUPPRESSION OF P53 AND C-MYC IN HUMAN PRIMARY CELLS

    Science.gov (United States)

    In apoptosis the tumor suppressor p53 and oncogene c-myc, are usually upregulated. However, we report here an alternate pathway of regulation that is triggered by inflammatory-associated matrix fragments of fibronectin (FN) and leads to apoptosis. It is mediated by transcriptio...

  12. Effect of up-regulated expression of tumor suppressor gene p14ARF on apoptosis of chronic myeloid leukemia cells

    Institute of Scientific and Technical Information of China (English)

    白元松

    2013-01-01

    Objective To investigate the effect of up-regulated expression of tumor suppressor gene p14ARFon apoptosis of chronic myeloid leukemia (CML) cells and its interaction with imatinib.Methods Tumor suppressor gene p14ARFwas transduced into K562 (K562-p14ARF) and 4blast crisis primary CML cells (CML-BC 1-4) using vesicular stomatitis virus glycoprotein (VSV-G)

  13. Effects of NANOG gene down-regulation on the apoptosis of T-cell acute lymphoblastic leukemia cells

    Institute of Scientific and Technical Information of China (English)

    曹江

    2014-01-01

    Objective To explore gene expression of NANOG in T-cell acute lymphoblastic leukemia(T-ALL)cell lines and the effects of NANOG gene down-regulation on apoptosis of leukemia cells.Methods Real-time PCR(RtPCR)and Western blot were used to detect the expression level of NANOG gene and protein in MOLT-4,CCRF-HSB2 and Jurkat cells.

  14. Induction of apoptosis in renal cell carcinoma by reactive oxygen species: involvement of extracellular signal-regulated kinase 1/2, p38delta/gamma, cyclooxygenase-2 down-regulation, and translocation of apoptosis-inducing factor.

    LENUS (Irish Health Repository)

    Ambrose, Monica

    2012-02-03

    Renal cell carcinoma (RCC) is the most common malignancy of the kidney. Unfortunately, RCCs are highly refractory to conventional chemotherapy, radiation therapy, and even immunotherapy. Thus, novel therapeutic targets need to be sought for the successful treatment of RCCs. We now report that 6-anilino-5,8-quinolinequinone (LY83583), an inhibitor of cyclic GMP production, induced growth arrest and apoptosis of the RCC cell line 786-0. It did not prove deleterious to normal renal epithelial cells, an important aspect of chemotherapy. To address the cellular mechanism(s), we used both genetic and pharmacological approaches. LY83583 induced a time- and dose-dependent increase in RCC apoptosis through dephosphorylation of mitogen-activated protein kinase kinase 1\\/2 and its downstream extracellular signal-regulated kinases (ERK) 1 and -2. In addition, we observed a decrease in Elk-1 phosphorylation and cyclooxygenase-2 (COX-2) down-regulation. We were surprised that we failed to observe an increase in either c-Jun NH(2)-terminal kinase or p38alpha and -beta mitogen-activated protein kinase activation. In contradiction, reintroduction of p38delta by stable transfection or overexpression of p38gamma dominant negative abrogated the apoptotic effect. Cell death was associated with a decrease and increase in Bcl-x(L) and Bax expression, respectively, as well as release of cytochrome c and translocation of apoptosis-inducing factor. These events were associated with an increase in reactive oxygen species formation. The antioxidant N-acetyl l-cysteine, however, opposed LY83583-mediated mitochondrial dysfunction, ERK1\\/2 inactivation, COX-2 down-regulation, and apoptosis. In conclusion, our results suggest that LY83583 may represent a novel therapeutic agent for the treatment of RCC, which remains highly refractory to antineoplastic agents. Our data provide a molecular basis for the anticancer activity of LY83583.

  15. TIPE2 Inhibits Lung Cancer Growth Attributing to Promotion of Apoptosis by Regulating Some Apoptotic Molecules Expression.

    Directory of Open Access Journals (Sweden)

    Qing-Qing Liu

    Full Text Available Recent studies found that TIPE2 was involved in cancer development. However, little is known about TIPE2 in lung cancer. Our study aims to clarify the role of TIPE2 in lung carcinogenesis. We examined the expression of TIPE2 in lung squamous cancer (LSC, small cell lung cancer and lung adenocarcinoma (AdC tissues and found that TIPE2 expression was lost in small cell lung cancer, compared with adjacent non-tumor tissues. Overexpression of TIPE2 significantly inhibited the growth of lung cancer cell H446 in vitro and even suppressed tumor formation in vivo. Flow cytometry analysis found TIPE2 overexpression promoted apoptosis of H446. In TIPE2 over-expression cells, caspase-3, caspase-9, and Bax were significantly up-regulated while Bcl-2 was down-regulated. Moreover, coincident results were shown by immunohistochemistry in tumors from nude mice. TIPE2 inhibited the phosphorylation of Akt, while promoting the phosphorylation of P38, but had no effect on IκBα and ERK pathway. Taken together, TIPE2 promoted lung cancer cell apoptosis through affecting apoptosis-related molecules caspase-3, caspase-9, Bcl-2 and Bax, possibly via regulating P38 and Akt pathways, indicating that TIPE2 might be a novel marker for lung cancer diagnosis and therapy.

  16. Differential regulation of spontaneous and immune complex-induced neutrophil apoptosis by proinflammatory cytokines. Role of oxidants, Bax and caspase-3.

    Science.gov (United States)

    Ottonello, Luciano; Frumento, Guido; Arduino, Nicoletta; Bertolotto, Maria; Dapino, Patrizia; Mancini, Marina; Dallegri, Franco

    2002-07-01

    Neutrophil apoptosis represents a crucial step in the mechanisms governing the resolution of neutrophilic inflammation. Several soluble mediators of inflammation modulate neutrophil survival, retarding their apoptosis, whereas neutrophil activation by immune complexes (IC) results in the acceleration of apoptosis. To investigate neutrophil fate at the site of inflammation, we studied the effects of interleukin (IL)-2, IL-6, IL-8, IL-15, GM-CSF, and fMLP on spontaneous and IC-induced neutrophil apoptosis and the mechanisms regulating the survival of these cells. Spontaneous apoptosis was inhibited by GM-CSF, IL-6, and IL-15, but only GM-CSF overturned IC-induced apoptosis. No role of oxidants on the modulation of IC-dependent apoptosis was found. Indeed, fMLP or GM-CSF augmented the IC-dependent oxidative response, whereas the other compounds were ineffective. CGD neutrophils showed low levels of spontaneous apoptosis, but when exposed to IC, underwent a sharp increment of the apoptotic rate in a GM-CSF-inhibitable manner. Conversely, the expression of the proapoptotic protein Bax in 18-h aged neutrophils was down-regulated by GM-CSF, IL-6, and IL-15. Furthermore, IC induced a nearly threefold Bax up-regulation, which was completely reversed only by GM-CSF. Accordingly, the spontaneous activity of caspase-3 was inhibited by GM-CSF, IL-6, and IL-15. Furthermore, IC induced a sharp increment of enzymatic activity, and only GM-CSF inhibited the IC-dependent acceleration. Our results show that apoptosis of resting and IC-activated neutrophils is regulated differently, GM-CSF being the most potent neutrophil antiapoptotic factor. The results also unveil the existence of an oxidant-independent, Bax- and caspase-3-dependent, intracellular pathway regulating neutrophil apoptosis.

  17. Down-regulation of PKHD1 induces cell apoptosis through PI3K and NF-{kappa}B pathways

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Liping [Division of Nephrology, Shenzhen People' s Hospital, Second Clinical Medical College, Jinan University, Shenzhen 518020 (China); Wang, Shixuan [Renal Division, Brigham and Women' s Hospital and Harvard Medical School, Boston, MA 02115 (United States); Hu, Chaofeng [Department of Pathophysiology, Medical College, Jinan University, Guangzhou, 510632 (China); Zhang, Xinzhou, E-mail: slp08@126.com [Division of Nephrology, Shenzhen People' s Hospital, Second Clinical Medical College, Jinan University, Shenzhen 518020 (China)

    2011-04-15

    Mutations in PKHD1 (polycystic kidney and hepatic disease gene 1) gene cause the autosomal recessive polycystic kidney disease (ARPKD). Fibrocystin/polyductin (FPC), encoded by PKHD1, is a membrane-associated receptor-like protein. Although it is widely accepted that cystogenesis is mostly due to aberrant cell proliferation and apoptosis, it is still unclear how apoptosis is regulated. The aim of this study is to analyze the relationship among apoptosis, phosphatidylinositol 3-kinase (PI3K)/Akt and nuclear factor {kappa}B (NF-{kappa}B) in FPC knockdown kidney cells. We show that PKHD1-silenced HEK293 cells demonstrate a higher PI3K/Akt activity. Selective inhibition of PI3K/Akt using LY294002 or wortmannin in these cells increases serum starvation-induced HEK293 cell apoptosis with a concomitant decrease in cell proliferation and higher caspase-3 activity. PI3K/Akt inhibition also leads to increased NF-{kappa}B activity in these cells. We conclude that the PI3K/Akt pathway is involved in apoptotic function in PKHD1-silenced cells, and PI3K/Akt inhibition correlates with upregulation of NF-{kappa}B activity. These observations provide a potential platform for determining FPC function and therapeutic investigation of ARPKD.

  18. Salinomycin activates AMP-activated protein kinase-dependent autophagy in cultured osteoblastoma cells: a negative regulator against cell apoptosis.

    Directory of Open Access Journals (Sweden)

    Lun-qing Zhu

    Full Text Available BACKGROUND: The malignant osteoblastoma has poor prognosis, thus the search for novel and more efficient chemo-agents against this disease is urgent. Salinomycin induces broad anti-cancer effects both in vivo and in vitro, however, its role in osteoblastoma is still not clear. KEY FINDINGS: Salinomycin induced both apoptosis and autophagy in cultured U2OS and MG-63 osteoblastoma cells. Inhibition of autophagy by 3-methyladenine (3-MA, or by RNA interference (RNAi of light chain 3B (LC3B, enhanced salinomycin-induced cytotoxicity and apoptosis. Salinomycin induced a profound AMP-activated protein kinase (AMPK activation, which was required for autophagy induction. AMPK inhibition by compound C, or by AMPKα RNAi prevented salinomycin-induced autophagy activation, while facilitating cancer cell death and apoptosis. On the other hand, the AMPK agonist AICAR promoted autophagy activation in U2OS cells. Salinomycin-induced AMPK activation was dependent on reactive oxygen species (ROS production in osteoblastoma cells. Antioxidant n-acetyl cysteine (NAC significantly inhibited salinomycin-induced AMPK activation and autophagy induction. CONCLUSIONS: Salinomycin activates AMPK-dependent autophagy in osteoblastoma cells, which serves as a negative regulator against cell apoptosis. AMPK-autophagy inhibition might be a novel strategy to sensitize salinomycin's effect in cancer cells.

  19. Leptin regulates proliferation and apoptosis of colorectal carcinoma through PI3K/Akt/mTOR signalling pathway

    Indian Academy of Sciences (India)

    Di Wang; Jian Chen; Hui Chen; Zhi Duan; Qimei Xu; Meiyan Wei; Lianghua Wang; Meizuo Zhong

    2012-03-01

    Epidemiological studies have indicated that obesity is associated with colorectal cancer. The obesity hormone leptin is considered as a key mediator for cancer development and progression. The present study aims to investigate regulatory effects of leptin on colorectal carcinoma. The expression of leptin and its receptor Ob-R was examined by immunohistochemistry in 108 Chinese patients with colorectal carcinoma. The results showed that leptin/Ob-R expression was significantly associated with T stage, TNM stage, lymph node metastasis, distant metastasis, differentiation and expression of p-mTOR, p-70S6 kinase, and p-Akt. Furthermore, the effects of leptin on proliferation and apoptosis of HCT-116 colon carcinoma cells were determined. The results showed that leptin could stimulate the proliferation and inhibit the apoptosis of HCT-116 colon cells through the PI3K/Akt/mTOR pathway. Ly294002 (a PI3K inhibitor) and rapamycin (an mTOR inhibitor) could prevent the regulatory effects of leptin on the proliferation and apoptosis of HCT-116 cells via abrogating leptin-mediated PI3K/Akt/mTOR pathway. All these results indicated that leptin could regulate proliferation and apoptosis of colorectal carcinoma through the PI3K/Akt/mTOR signalling pathway.

  20. Inhibitor of apoptosis (IAP) proteins in regulation of inflammation and innate immunity

    DEFF Research Database (Denmark)

    Damgaard, Rune B; Gyrd-Hansen, Mads

    2011-01-01

    Inflammatory and innate immune signaling in response to recognition of pathogens is essential for immunity and host survival. However, deregulation may lead to detrimental pathologies including immunodeficiency, inflammatory diseases, and cancer. Inhibitor of apoptosis (IAP) proteins have emerged...

  1. The Regulating Effect of CCK and Gastrin on Apoptosis of Bile Duct Carcinoma Cells

    Institute of Scientific and Technical Information of China (English)

    MAKuansheng; ZHANGFengshen; HEZhenping; DONGJiahong

    2002-01-01

    Objective:Probe into the influence and the mechanisms of CCK and gastrin on the apoptosis of bile duct carcinoma cells. Methods:By taking beauvericin as the revulsant to the apoptosis of bile duct carcinoma cells, the influence of CCK and gastrin on the apoptosis of bile duct carcinoma cells was investigated by using the teehniques such as TUNEL fluorescent staining, stream mode cell detecting instrument and reverse bcl-2 oligonucleotide. Techifiques of immunohistochemistry, in situ hybridization,flow cytometry(FCM),RT-PCR were used to study the roles of apoptosis-related genes bcl-2 and bax Results:After beauvericin 40 μM worked for 12 h, the survival rate of QBC939 bile duct carcinoma cells was decreased by 35%-40%.About 80% of the bile duct carcinoma cells showed various degrees of apoptosis.CCK and gastrin could upregulate the threshold value of the apoptosis of bile duct carcinoma cells, which could be inhibited by L60,L18 and reverse bcl-2 oligonucleotide. In terms of both transcription and translating levels,CCK and gastrin could obviously promote the genetic expression of bel-2,but had no influence on the genetic expression of bax. Addition of CCK-A receptor or CCK-B/gastr in receptor antagonist could remarkably inhibit the expression of bel-2 boosted by gastrin-17 and CCK-8S. Conclusion:CCK and gastrin inhibited the apoptosis of bile duct carcinoma cells through upregulating the genetic expression of bcl-2.Theoretically, this research has expanded our understanding to the mechanism of CCK and gastrin in controlling the growth of tumors, enriched our view to the mechanism of apoptosis of alimentary tract tumors, and has provided a new thinking for the assistant treatment to bile duct carcinoma cells as well.

  2. Molecular Regulation of DNA Damage-Induced Apoptosis in Neurons of Cerebral Cortex

    OpenAIRE

    Martin, Lee J.; Liu, Zhiping; Pipino, Jacqueline; Chestnut, Barry; Landek, Melissa A.

    2008-01-01

    Cerebral cortical neuron degeneration occurs in brain disorders manifesting throughout life, but the mechanisms are understood poorly. We used cultured embryonic mouse cortical neurons and an in vivo mouse model to study mechanisms of DNA damaged-induced apoptosis in immature and differentiated neurons. p53 drives apoptosis of immature and differentiated cortical neurons through its rapid and prominent activation stimulated by DNA strand breaks induced by topoisomerase-I and -II inhibition. B...

  3. Attenuation of p53 expression and Bax down-regulation during phorbol ester mediated inhibition of apoptosis

    OpenAIRE

    Meßmer, Udo K; Brüne, Bernhard

    1997-01-01

    Nitric oxide (NO) caused apoptotic cell death in murine RAW 264.7 macrophages. Associated with apoptotic morphology we observed p53 up-regulation and increased Bax expression. 12-O-tetradecanoylphorbol-13-acetate (TPA), a protein kinase C (PKC) activator potently blocked NO-induced apoptosis. To gain insights into the mechanisms involved we investigated the effect of TPA on apoptotic conveying proteins such as p53 and Bax.TPA (100 nM) attentuated p53 up-regulation elicited by the NO-releasing...

  4. American Ginseng Stimulates Insulin Production and Prevents Apoptosis through Regulation of Uncoupling Protein-2 in Cultured β Cells

    Directory of Open Access Journals (Sweden)

    John Zeqi Luo

    2006-01-01

    Full Text Available American ginseng root displays the ability to achieve glucose homeostasis both experimentally and clinically but the unknown mechanism used by ginseng to achieve its therapeutic effects on diabetes limits its application. Disruption in the insulin secretion of pancreatic β cells is considered the major cause of diabetes. A mitochondrial protein, uncoupling protein-2 (UCP-2 has been found to play a critical role in insulin synthesis and β cell survival. Our preliminary studies found that the extracts of American ginseng inhibit UCP-2 expression which may contribute to the ability of ginseng protecting β cell death and improving insulin synthesis. Therefore, we hypothesized that ginseng extracts suppress UCP-2 in the mitochondria of pancreatic β cells, promoting insulin synthesis and anti-apoptosis (a programmed cell-death mechanism. To test the hypothesis, the serum-deprived quiescent β cells were cultured with or without interleukin-1β (IL-1β, (200 pg ml−1, a cytokine to induce β cell apoptosis and water extracts of American ginseng (25 μg per 5 μl administered to wells of 0.5 ml culture for 24 h. We evaluated effects of ginseng on UCP-2 expression, insulin production, anti-/pro-apoptotic factors Bcl-2/caspase-9 expression and cellular ATP levels. We found that ginseng suppresses UCP-2, down-regulates caspase-9 while increasing ATP and insulin production/secretion and up-regulates Bcl-2, reducing apoptosis. These findings suggest that stimulation of insulin production and prevention of β cell loss by American ginseng extracts can occur via the inhibition of mitochondrial UCP-2, resulting in increase in the ATP level and the anti-apoptotic factor Bcl-2, while down-regulation of pro-apoptotic factor caspase-9 occurs, lowering the occurrence of apoptosis, which support the hypothesis.

  5. Zeb1 Is a Potential Regulator of Six2 in the Proliferation, Apoptosis and Migration of Metanephric Mesenchyme Cells

    Science.gov (United States)

    Gu, Yuping; Zhao, Ya; Zhou, Yuru; Xie, Yajun; Ju, Pan; Long, Yaoshui; Liu, Jianing; Ni, Dongsheng; Cao, Fen; Lyu, Zhongshi; Mao, Zhaomin; Hao, Jin; Li, Yiman; Wan, Qianya; Kanyomse, Quist; Liu, Yamin; Ren, Die; Ning, Yating; Li, Xiaofeng; Zhou, Qin; Li, Bing

    2016-01-01

    Nephron progenitor cells surround around the ureteric bud tips (UB) and inductively interact with the UB to originate nephrons, the basic units of renal function. This process is determined by the internal balance between self-renewal and consumption of the nephron progenitor cells, which is depending on the complicated regulation networks. It has been reported that Zeb1 regulates the proliferation of mesenchymal cells in mouse embryos. However, the role of Zeb1 in nephrons generation is not clear, especially in metanephric mesenchyme (MM). Here, we detected cell proliferation, apoptosis and migration in MM cells by EdU assay, flow cytometry assay and wound healing assay, respectively. Meanwhile, Western and RT-PCR were used to measure the expression level of Zeb1 and Six2 in MM cells and developing kidney. Besides, the dual-luciferase assay was conducted to study the molecular relationship between Zeb1 and Six2. We found that knock-down of Zeb1 decreased cell proliferation, migration and promoted cell apoptosis in MM cells and Zeb1 overexpression leaded to the opposite data. Western-blot and RT-PCR results showed that knock-down of Zeb1 decreased the expression of Six2 in MM cells and Zeb1 overexpression contributed to the opposite results. Similarly, Zeb1 promoted Six2 promoter reporter activity in luciferase assays. However, double knock-down of Zeb1 and Six2 did not enhance the apoptosis of MM cells compared with control cells. Nevertheless, double silence of Zeb1 and Six2 repressed cell proliferation. In addition, we also found that Zeb1 and Six2 had an identical pattern in distinct developing phases of embryonic kidney. These results indicated that there may exist a complicated regulation network between Six2 and Zeb1. Together, we demonstrate Zeb1 promotes proliferation and apoptosis and inhibits the migration of MM cells, in association with Six2. PMID:27509493

  6. Nutrient/serum starvation derived TRIP-Br3 down-regulation accelerates apoptosis by destabilizing XIAP

    Science.gov (United States)

    Lee, Soonduck; Jeong, Dongjun; Yang, Young; Kim, Keun-Il; Lim, Jong-Seok; Cheon, Chung-Il; Kim, Changjin; Kang, Young-Sook; Lee, Myeong-Sok

    2015-01-01

    TRIP-Br3 and TRIP-Br1 have shown to have important biological functions. However, the function of TRIP-Br3 in tumorigenesis is not well characterized compared to oncogenic TRIP-Br1. Here, we investigated the function of TRIP-Br3 in tumorigenesis by comparing with that of TRIP-Br1. Under nutrient/serum starvation, TRIP-Br3 expression was down-regulated slightly in cancer cells and significantly in normal cells. Unexpectedly, TRIP-Br1 expression was greatly up-regulated in cancer cells but not in normal cells. Moreover, TRIP-Br3 activated autophagy while TRIP-Br1 inactivated it under serum starvation. In spite of different expression and roles of TRIP-Br3 and TRIP-Br1, both of them alleviate cell death by directly binding to and stabilizing XIAP, a potent apoptosis inhibitor, through blocking its ubiquitination. Taken together, we propose that TRIP-Br3 primarily activates the autophagy and suppresses apoptosis in nutrient sufficient condition. However, the prolonged extreme stressful condition of nutrient starvation causes a dramatic decrease of TRIP-Br3, which in turn induces apoptosis by destabilizing XIAP. Up-regulated TRIP-Br1 in cancer cells compensates this effect and delays apoptosis. This can be explained by the competitive alternative binding of TRIP-Br3 and TRIP-Br1 to the BIR2 domain of XIAP. In an extended study, our immunohistochemical analysis revealed a markedly lower level of TRIP-Br3 protein in human carcinoma tissues compared to normal epithelial tissues, implying the role of TRIP-Br3 as a tumor suppressor rather than onco-protein. PMID:25691055

  7. Up-regulation of eEF1A2 promotes proliferation and inhibits apoptosis in prostate cancer

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Yue [Department of Pathology, The First Affiliated Hospital, Zhejiang University Medical College, Hangzhou (China); Du, Chengli [Department of Hepatobiliary Surgery, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou (China); Wang, Bo; Zhang, Yanling; Liu, Xiaoyan [Department of Pathology, The First Affiliated Hospital, Zhejiang University Medical College, Hangzhou (China); Ren, Guoping, E-mail: renguoping12345@163.com [Department of Pathology, The First Affiliated Hospital, Zhejiang University Medical College, Hangzhou (China)

    2014-07-18

    Highlights: • The expression of eEF1A2 is up-regulated in prostate cancer tissues. • Suppression of eEF1A2 inhibits the proliferation and promotes apoptosis. • Inhibition of eEF1A2 enhances the expression of apoptotic relevant proteins. • The expressions of eEF1A2 and cleavage-caspase3 are inversely correlated. - Abstract: Background: eEF1A2 is a protein translation factor involved in protein synthesis, which possesses important function roles in cancer development. This study aims at investigating the expression pattern of eEF1A2 in prostate cancer and its potential role in prostate cancer development. Methods: We examined the expression level of eEF1A2 in 30 pairs of prostate cancer tissues by using RT-PCR and immunohistochemical staining (IHC). Then we applied siRNA specifically targeting eEF1A2 to down-regulate its expression in DU-145 and PC-3 cells. Flow cytometer was used to explore apoptosis and Western-blot was used to detect the pathway proteins of apoptosis. Results: Our results showed that the expression level of eEF1A2 in prostate cancer tissues was significantly higher compared to their corresponding normal tissues. Reduction of eEF1A2 expression in DU-145 and PC-3 cells led to a dramatic inhibition of proliferation accompanied with enhanced apoptosis rate. Western blot revealed that apoptosis pathway proteins (caspase3, BAD, BAX, PUMA) were significantly up-regulated after suppression of eEF1A2. More importantly, the levels of eEF1A2 and caspase3 were inversely correlated in prostate cancer tissues. Conclusion: Our data suggests that eEF1A2 plays an important role in prostate cancer development, especially in inhibiting apoptosis. So eEF1A2 might serve as a potential therapeutic target in prostate cancer.

  8. Melatonin-mediated Bim up-regulation and cyclooxygenase-2 (COX-2) down-regulation enhances tunicamycin-induced apoptosis in MDA-MB-231 cells.

    Science.gov (United States)

    Woo, Seon Min; Min, Kyoung-jin; Kwon, Taeg Kyu

    2015-04-01

    Melatonin is involved in many physiological functions, and it has differential effects on apoptosis in normal and cancer cells. However, the mechanism of its antitumor roles is not well understood. In this study, we show that melatonin enhances tunicamycin-induced apoptosis in human breast carcinoma MDA-MB-231 cells. Melatonin up-regulates pro-apoptotic protein Bim expression at the transcriptional levels in the presence of tunicamycin. Melatonin inhibits tunicamycin-induced COX-2 expression in MDA-MB-231 cells. Furthermore, inhibition of COX-2 activity using the COX-2 inhibitor, NS398, increases tunicamycin-induced apoptosis. Interestingly, these effects were not associated with melatonin receptor signal pathways. Pertussis toxin (a general Gi protein inhibitor) or luzindole (a nonspecific melatonin receptor antagonist) did not reverse the effect of melatonin. In addition, melatonin blocked tunicamycin-induced NF-κB transcriptional activity, p65 nuclear translocation, and p38 MAPK activation. Melatonin-mediated p38 MAPK inhibition contributed to decreased COX-2 mRNA stability. Taken together, our results suggest that melatonin enhances antitumor function through up-regulation of Bim expression and down-regulation of COX-2 expression in tunicamycin-treated MDA-MB-231 cells. PMID:25711465

  9. Inhibition of Calcium Influx Reduces Dysfunction and Apoptosis in Lipotoxic Pancreatic β-Cells via Regulation of Endoplasmic Reticulum Stress.

    Directory of Open Access Journals (Sweden)

    Yuren Zhou

    Full Text Available Lipotoxicity plays an important role in pancreatic β-cell failure during the development of type 2 diabetes. Prolonged exposure of β-cells to elevated free fatty acids level could cause deterioration of β-cell function and induce cell apoptosis. Therefore, inhibition of fatty acids-induced β-cell dysfunction and apoptosis might provide benefit for the therapy of type 2 diabetes. The present study examined whether regulation of fatty acids-triggered calcium influx could protect pancreatic β-cells from lipotoxicity. Two small molecule compounds, L-type calcium channel blocker nifedipine and potassium channel activator diazoxide were used to inhibit palmitic acid-induced calcium influx. And whether the compounds could reduce palmitic acid-induced β-cell failure and the underlying mechanism were also investigated. It was found that both nifedipine and diazoxide protected MIN6 pancreatic β-cells and primary cultured murine islets from palmitic acid-induced apoptosis. Meanwhile, the impaired insulin secretion was also recovered to varying degrees by these two compounds. Our results verified that nifedipine and diazoxide could reduce palmitic acid-induced endoplasmic reticulum stress to generate protective effects on pancreatic β-cells. More importantly, it suggested that regulation of calcium influx by small molecule compounds might provide benefits for the prevention and therapy of type 2 diabetes.

  10. Progress in the Study of Acupuncture in Regulating Post-Cerebral Ischemia/Reperfusion Cell-Apoptosis Related Gene Expression

    Institute of Scientific and Technical Information of China (English)

    卜渊; 耿德勤; 曾因明

    2003-01-01

    @@ Cerebralvascular disease has already become one of the serious illnesses that threatens human health. Along with the development of medicine, although the therapeutic method harvested huge progress, currently ideal therapeutic methods are lacking. The conventional acupuncture has definite therapeutic effect on cerebropathy. Clinical practice and various animal experiments confirmed that acupuncture could alleviate the pathologic damage after cerebral ischemic injury and promote the nerve function recovery. Past studies showed that the role of acupuncture in treating cerebral ischemia is realized through alleviating post-ischemic neuron necrosis, while recent study discovered that acupuncture has inhibitory effect on post-ischemia induced neuronal necrosis(1), which brought the mechanism of acupuncture in treating cerebral ischemia from the biochemical and metabolical level to the molecular biologic level. The studies revealed that after cerebral ischemia, many genes were induced to express themselves, protein product they coded directly or indirectly participated in the regulation of post-cerebral ischemia apoptosis of neuron, some promoting the apoptosis, while others inhibiting apoptosis with some of the function still unclear. The anti-apoptotic effect of acupuncture is accomplished through regulating the relevant apoptotic gene expression(2), and now it is reviewed as follows:

  11. The flavonoid casticin enhances TRAIL-induced apoptosis of colon cancer cells through endoplasmic reticulum stress-mediated up-regulation of DR5

    Institute of Scientific and Technical Information of China (English)

    Sanyuan Tang; Guangjin Yuan; Zhengyang Yu; Leilan Yin; Hao Jiang

    2013-01-01

    Objective: The aim of this study was to explore the mechanisms by which the flavonoid casticin enhances tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)-induced apoptosis in colon cancer cells. Methods: Human colon cancer HT-29 cells were treated with TRAIL or casticin. Cytotoxicity was examined by MTT assay, and apoptosis determined by morphological observation and flow cytometric analysis. Death receptor 5 (DR5), DR4, and endoplasmic reticulum (ER) stress response markers, including glucose regulating protein 78 (GRP78), activating transcription factor 4 (ATF4) and CHOP (CCAAT/enhancer binding protein homologous protein), were examined with western blot. Small interfering RNA (siRNA) transfection was employed to knock down CHOP. Results: HT-29 cells were resistance to TRAIL-induced apoptosis, but casticin, at subtoxic concentrations, potentiated HT-29 cells to TRAIL-induced apoptosis. Casticin up-regulated the expression of DR5 time- and dose-dependent manners, but had no effect on the expression of DR4. Also, casticin increased the levels of ER stress response markers (GRP78, ATF4 and CHOP) in a similar way to DR5. Knockdown of CHOP by specific siRNA, or salubrinal, an ER stress inhibitor, abolished the up-regulation of DR5 and enhancement of TRAIL-induced apoptosis by casticin. Conclusion: Casticin enhances TRAIL-induced apoptosis of colon cancer cells by ER stress-mediated up-regulation of DR5.

  12. High glucose induced oxidative stress and apoptosis in cardiac microvascular endothelial cells are regulated by FoxO3a.

    Directory of Open Access Journals (Sweden)

    Chaoming Peng

    Full Text Available AIM: Cardiac microvascular endothelial cells (CMECs dysfunction contributes to cardiovascular complications in diabetes, whereas, the underlying mechanism is not fully clarified. FoxO transcription factors are involved in apoptosis and reactive oxygen species (ROS production. Therefore, the present study was designed to elucidate the potential role of FoxO3a on the CMECs injury induced by high glucose. MATERIALS AND METHODS: CMECs were isolated from hearts of adult rats and cultured in normal or high glucose medium for 6 h, 12 h and 24 h respectively. To down-regulate FoxO3a expression, CMECs were transfected with FoxO3a siRNA. ROS accumulation and apoptosis in CMECs were assessed by dihydroethidine (DHE staining and TUNEL assay respectively. Moreover, the expressions of Akt, FoxO3a, Bim and BclxL in CMECs were assessed by Western blotting assay. RESULTS: ROS accumulation in CMECs was significantly increased after high glucose incubation for 6 to 24 h. Meanwhile, high glucose also increased apoptosis in CMECs, correlated with decreased the phosphorylation expressions of Akt and FoxO3a. Moreover, high glucose incubation increased the expression of Bim, whereas increased anti-apoptotic protein BclxL. Furthermore, siRNA target FoxO3a silencing enhanced the ROS accumulation, whereas suppressed apoptosis in CMECs. FoxO3a silencing also abolished the disturbance of Bcl-2 proteins induced by high glucose in CMECs. CONCLUSION: Our data provide evidence that high glucose induced FoxO3a activation which suppressed ROS accumulation, and in parallel, resulted in apoptosis of CMECs.

  13. Simulated Microgravity Promotes Cell Apoptosis Through Suppressing Uev1A/TICAM/TRAF/NF-κB-Regulated Anti-Apoptosis and p53/PCNA- and ATM/ATR-Chk1/2-Controlled DNA-Damage Response Pathways.

    Science.gov (United States)

    Zhao, Tuo; Tang, Xin; Umeshappa, Channakeshava Sokke; Ma, Hong; Gao, Haijun; Deng, Yulin; Freywald, Andrew; Xiang, Jim

    2016-09-01

    Microgravity has been known to induce cell death. However, its underlying mechanism is less studied. In this study, BL6-10 melanoma cells were cultured in flasks under simulated microgravity (SMG). We examined cell apoptosis, and assessed expression of genes associated with apoptosis and genes regulating apoptosis in cells under SMG. We demonstrate that SMG induces cell morphological changes and microtubule alterations by confocal microscopy, and enhances apoptosis by flow cytometry, which was associated with up- and down-regulation of pro-apoptotic and anti-apoptotic genes, respectively. Moreover, up- and down-regulation of pro-apoptotic (Caspases 3, 7, 8) and anti-apoptotic (Bcl2 and Bnip3) molecules was confirmed by Western blotting analysis. Western blot analysis also indicates that SMG causes inhibition of an apoptosis suppressor, pNF-κB-p65, which is complemented by the predominant localization of NF-κB-p65 in the cytoplasm. SMG also reduces expression of molecules regulating the NF-κB pathway including Uev1A, TICAM, TRAF2, and TRAF6. Interestingly, 10 DNA repair genes are down-regulated in cells exposed to SMG, among which down-regulation of Parp, Ercc8, Rad23, Rad51, and Ku70 was confirmed by Western blotting analysis. In addition, we demonstrate a significant inhibition of molecules involved in the DNA-damage response, such as p53, PCNA, ATM/ATR, and Chk1/2. Taken together, our work reveals that SMG promotes the apoptotic response through a combined modulation of the Uev1A/TICAM/TRAF/NF-κB-regulated apoptosis and the p53/PCNA- and ATM/ATR-Chk1/2-controlled DNA-damage response pathways. Thus, our investigation provides novel information, which may help us to determine the cause of negative alterations in human physiology occurring at spaceflight environment. J. Cell. Biochem. 117: 2138-2148, 2016. © 2016 Wiley Periodicals, Inc. PMID:26887372

  14. α-Hispanolol sensitizes hepatocellular carcinoma cells to TRAIL-induced apoptosis via death receptor up-regulation

    Energy Technology Data Exchange (ETDEWEB)

    Mota, Alba, E-mail: amota@iib.uam.es [Unidad de Terapias Farmacológicas, Área de Genética Humana, Instituto de Investigación de Enfermedades Raras (IIER), Instituto de Salud Carlos III, Madrid (Spain); Jiménez-Garcia, Lidia, E-mail: ljimenez@isciii.es [Unidad de Terapias Farmacológicas, Área de Genética Humana, Instituto de Investigación de Enfermedades Raras (IIER), Instituto de Salud Carlos III, Madrid (Spain); Herránz, Sandra, E-mail: sherranz@isciii.es [Unidad de Terapias Farmacológicas, Área de Genética Humana, Instituto de Investigación de Enfermedades Raras (IIER), Instituto de Salud Carlos III, Madrid (Spain); Heras, Beatriz de las, E-mail: lasheras@ucm.es [Departamento de Farmacología, Facultad de Farmacia, Universidad Complutense de Madrid (UCM), Madrid (Spain); Hortelano, Sonsoles, E-mail: shortelano@isciii.es [Unidad de Terapias Farmacológicas, Área de Genética Humana, Instituto de Investigación de Enfermedades Raras (IIER), Instituto de Salud Carlos III, Madrid (Spain)

    2015-08-01

    Hispanolone derivatives have been previously described as anti-inflammatory and antitumoral agents. However, their effects on overcoming Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) resistance remain to be elucidated. In this study, we analyzed the cytotoxic effects of the synthetic hispanolone derivative α-hispanolol (α-H) in several tumor cell lines, and we evaluated the induction of apoptosis, as well as the TRAIL-sensitizing potential of α-H in the hepatocellular carcinoma cell line HepG2. Our data show that α-H decreased cell viability in a dose-dependent manner in HeLa, MDA-MB231, U87 and HepG2 cell lines, with a more prominent effect in HepG2 cells. Interestingly, α-H had no effect on non-tumoral cells. α-H induced activation of caspase-8 and caspase-9 and also increased levels of the proapoptotic protein Bax, decreasing antiapoptotic proteins (Bcl-2, X-IAP and IAP-1) in HepG2 cells. Specific inhibition of caspase-8 abrogated the cascade of caspase activation, suggesting that the extrinsic pathway has a critical role in the apoptotic events induced by α-H. Furthermore, combined treatment of α-H with TRAIL enhanced apoptosis in HepG2 cells, activating caspase-8 and caspase-9. This correlated with up-regulation of both the TRAIL death receptor DR4 and DR5. DR4 or DR5 neutralizing antibodies abolished the effect of α-H on TRAIL-induced apoptosis, suggesting that sensitization was mediated through the death receptor pathway. Our results demonstrate that α-H induced apoptosis in the human hepatocellular carcinoma cell line HepG2 through activation of caspases and induction of the death receptor pathway. In addition, we describe a novel function of α-H as a sensitizer on TRAIL-induced apoptotic cell death in HepG2 cells. - Highlights: • α-Hispanolol induced apoptosis in the human hepatocellular carcinoma cell line HepG2. • α-Hispanolol induced activation of caspases and the death receptor pathway. • α-Hispanolol enhanced

  15. Role of the tumor microenvironment in regulating apoptosis and cancer progression.

    Science.gov (United States)

    Yaacoub, Katherine; Pedeux, Remy; Tarte, Karin; Guillaudeux, Thierry

    2016-08-10

    Apoptosis is a gene-directed program that is engaged to efficiently eliminate dysfunctional cells. Evasion of apoptosis may be an important gate to tumor initiation and therapy resistance. Like any other developmental program, apoptosis can be disrupted by several genetic aberrations driving malignant cells into an uncontrolled progression and survival. For its sustained growth, cancer develops in a complex environment, which provides survival signals and rescues malignant cells from apoptosis. Recent studies have clearly shown a wide interaction between tumor cells and their microenvironment, confirming the influence of the surrounding cells on tumor expansion and invasion. These non-malignant cells not only intensify tumor cells growth but also upgrade the process of metastasis. The strong crosstalk between malignant cells and a reactive microenvironment is mediated by soluble chemokines and cytokines, which act on tumor cells through surface receptors. Disturbing the microenvironment signaling might be an encouraging approach for patient's treatment. Therefore, the ultimate knowledge of "tumor-microenvironment" interactions facilitates the identification of novel therapeutic procedures that mobilize cancer cells from their supportive cells. This review focuses on cancer progression mediated by the dysfunction of apoptosis and by the fundamental relationship between tumor and reactive cells. New insights and valuable targets for cancer prevention and therapy are also presented. PMID:27224890

  16. Inhibition of precancerous lesions development in kidneys by chrysin via regulating hyperproliferation, inflammation and apoptosis at pre clinical stage.

    Science.gov (United States)

    Rashid, Summya; Nafees, Sana; Vafa, Abul; Afzal, Shekh Muhammad; Ali, Nemat; Rehman, Muneeb U; Hasan, Syed Kazim; Siddiqi, Aisha; Barnwal, Preeti; Majed, Ferial; Sultana, Sarwat

    2016-09-15

    Chrysin (CH) is natural, biologically active compound, belongs to flavoniod family and possesses diverse pharmacological activities as anti-inflammatory, anti-oxidant and anti-cancer. It is found in many plants, honey and propolis. In the present study, we investigated the chemopreventive efficacy of CH against N-nitrosodiethylamine (DEN) initiated and Fe-NTA induced precancerous lesions and its role in regulating oxidative injury, hyperproliferation, tumor incidences, histopathological alterations, inflammation, and apoptosis in the kidneys of Wistar rats. Renal cancer was initiated by single intraperitoneal (i.p.) injection of DEN (200 mg/kg bw) and promoted by twice weekly injection of ferric nitrilotriacetate (Fe-NTA) 9 mg Fe/kg bw for 16 weeks. CH attenuated Fe-NTA enhanced renal lipid peroxidation, serum toxicity markers and restored renal anti oxidant armory significantly. CH supplementation suppressed the development of precancerous lesions via down regulation of cell proliferation marker like PCNA; inflammatory mediators like TNF-α, IL-6, NFkB, COX-2, iNOS; tumor incidences. CH up regulated intrinsic apoptotic pathway proteins like bax, caspase-9 and caspase-3 along with down regulation of Bcl-2 triggering apoptosis. Histopathological and ultra structural alterations further confirmed biochemical and immunohistochemical results. These results provide powerful evidence for the chemopreventive efficacy of CH against chemically induced renal carcinogenesis possibly by modulation of multiple molecular pathways. PMID:27403965

  17. Hydrogen sulfide donor regulates alveolar epithelial cell apoptosis in rats with acute lung injury

    Institute of Scientific and Technical Information of China (English)

    LIU Wen-li; LIU Zhi-wei; LI Tian-shui; WANG Cong; ZHAO Bin

    2013-01-01

    Background Acute lung injury (ALl) is a common syndrome associated with high morbidity and mortality in emergency medicine.Cell apoptosis plays a key role in the pathogenesis of ALl.Hydrogen sulfide (H2S) plays a protective role during acute lung injury.We designed this study to examine the role of H2S in the lung alveolar epithelial cell apoptosis in rats with ALl.Methods Sixty-nine male Sprague Dawley rats were used.ALl was induced by intra-tail vein injection of oleic acid (OA).NaHS solution was injected intraperitonally 30 minutes before OA injection as the NaHS pretreatment group.Single sodium hydrosulfide pretreatment group and control group were designed.Index of quantitative assessment (IQA),wet/dry weight (W/D) ratio and the percentage of polymorphonuclear leukocyte (PMN) cells in the bronchoalveolar lavage fluid (BALF) were determined.H2S level in lung tissue was measured by a sensitive sulphur electrode.Apoptosis was evaluated by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining and Fas protein was measured by immunohistochemical staining.Results The level of endogenous H2S in lung tissue decreased with the development of ALl induced by OA injection.Apoptosis and Fas protein in alveolar epithelial cells increased in the ALl of rats but NaHS lessened apoptosis and Fas protein expression in alveolar epithelial cells of rats with ALl.Conclusion Endogenous H2S protects rats from oleic acid-induced ALl,probably by inhibiting cell apoptosis.

  18. Reactive oxygen species regulated mitochondria-mediated apoptosis in PC12 cells exposed to chlorpyrifos

    International Nuclear Information System (INIS)

    Reactive oxidative species (ROS) generated by environmental toxicants including pesticides could be one of the factors underlying the neuronal cell damage in neurodegenerative diseases. In this study we found that chlorpyrifos (CPF) induced apoptosis in dopaminergic neuronal components of PC12 cells as demonstrated by the activation of caspases and nuclear condensation. Furthermore, CPF also reduced the tyrosine hydroxylase-positive immunoreactivity in substantia nigra of the rat. In addition, CPF induced inhibition of mitochondrial complex I activity. Importantly, N-acetyl cysteine (NAC) treatment effectively blocked apoptosis via the caspase-9 and caspase-3 pathways while NAC attenuated the inhibition of mitochondrial complex I activity as well as the oxidative metabolism of dopamine (DA). These results demonstrated that CPF-induced apoptosis was involved in mitochondrial dysfunction through the production of ROS. In the response of cellular antioxidant systems to CPF, we found that CPF treatment increased HO-1 expression while the expression of CuZnSOD and MnSOD was reduced. In addition, we found that CPF treatment activated MAPK pathways, including ERK 1/2, the JNK, and the p38 MAP kinase in a time-dependent manner. NAC treatment abolished MAPK phosphorylation caused by CPF, indicating that ROS are upstream signals of MAPK. Interestingly, MAPK inhibitors abolished cytotoxicity and reduced ROS generation by CPF treatment. Our results demonstrate that CPF induced neuronal cell death in part through MAPK activation via ROS generation, suggesting its potential to generate oxidative stress via mitochondrial damage and its involvement in oxidative stress-related neurodegenerative disease. -- Highlights: ► Chlorpyrifos induces apoptosis. ► Chlorpyrifos inhibits mitochondrial complex I activity. ► ROS is involved in chlorpyrifos-induced apoptosis. ► Chlorpyrifos affects cellular antioxidant systems. ► Chlorpyrifos-induced apoptosis mediates activation of MAPK.

  19. Phosphatidylinositol 3-kinase/Akt pathway regulates hepatic stellate cell apoptosis

    Institute of Scientific and Technical Information of China (English)

    Yan Wang; Xiao-Yu Jiang; Li Liu; Hui-Qing Jiang

    2008-01-01

    AIM:To investigate the role of phosphatidylinositol 3-kinase(PI 3-K)/Akt signaling pathway in the balance of HSC activation and apoptosis in rat hepatic stellate cells(HSC).METHODS:An activated HSC cell line was used in this study.LY 294002,the PI 3-K/Akt signal pathway blocker was used to investigate the molecular events on apoptosis in HSC and to interpret the role of this pathway in HSC apoptosis.Immunocytochemistry,Western blot and reverse transcription polymerase chain reaction(RT-PCR)analysis were applied to detect the expression of PI 3-K,and simultaneously phosphorylated-Akt(p-Akt)and total-Akt were determined by Western blot.The HSC apoptosis was examined by annexin-V/propidium iodide double-labelled flow cytometry and transmission electron microscopy.RESULTS:The apoptosis rates in LY 294002(30.82% ±2.90%)and LY 294002+PDGF-BB(28.16%±2.58%)groups were significantly increased compared with those of control(9.02%±1.81%)and PDGF-BB(4.35%±1.18%).PDGF-BB augmented PI 3-K and p-Akt expression.LY 294002 significantly reduced the contents of PI 3-K and p-Akt.mRNA transcription evaluated by RT-PCR showed similar tendencies as protein expression.CONCLUSION:Inhibition of PI 3-K/Akt signaling pathway Induces apoptosis in HSC.(C)2008 The WJG Press.All rights reserved.

  20. Reactive oxygen species regulated mitochondria-mediated apoptosis in PC12 cells exposed to chlorpyrifos

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jeong Eun [Department of Pharmacology, College of Medicine, Hanyang University, Seoul (Korea, Republic of); Hanyang Biomedical Research Institute, Seoul (Korea, Republic of); Park, Jae Hyeon [Hanyang Biomedical Research Institute, Seoul (Korea, Republic of); Graduate School of Biomedical Science and Engineering, Hanyang University, Seoul (Korea, Republic of); Shin, In Chul [Department of Pharmacology, College of Medicine, Hanyang University, Seoul (Korea, Republic of); Koh, Hyun Chul, E-mail: hckoh@hanyang.ac.kr [Department of Pharmacology, College of Medicine, Hanyang University, Seoul (Korea, Republic of); Hanyang Biomedical Research Institute, Seoul (Korea, Republic of); Graduate School of Biomedical Science and Engineering, Hanyang University, Seoul (Korea, Republic of)

    2012-09-01

    Reactive oxidative species (ROS) generated by environmental toxicants including pesticides could be one of the factors underlying the neuronal cell damage in neurodegenerative diseases. In this study we found that chlorpyrifos (CPF) induced apoptosis in dopaminergic neuronal components of PC12 cells as demonstrated by the activation of caspases and nuclear condensation. Furthermore, CPF also reduced the tyrosine hydroxylase-positive immunoreactivity in substantia nigra of the rat. In addition, CPF induced inhibition of mitochondrial complex I activity. Importantly, N-acetyl cysteine (NAC) treatment effectively blocked apoptosis via the caspase-9 and caspase-3 pathways while NAC attenuated the inhibition of mitochondrial complex I activity as well as the oxidative metabolism of dopamine (DA). These results demonstrated that CPF-induced apoptosis was involved in mitochondrial dysfunction through the production of ROS. In the response of cellular antioxidant systems to CPF, we found that CPF treatment increased HO-1 expression while the expression of CuZnSOD and MnSOD was reduced. In addition, we found that CPF treatment activated MAPK pathways, including ERK 1/2, the JNK, and the p38 MAP kinase in a time-dependent manner. NAC treatment abolished MAPK phosphorylation caused by CPF, indicating that ROS are upstream signals of MAPK. Interestingly, MAPK inhibitors abolished cytotoxicity and reduced ROS generation by CPF treatment. Our results demonstrate that CPF induced neuronal cell death in part through MAPK activation via ROS generation, suggesting its potential to generate oxidative stress via mitochondrial damage and its involvement in oxidative stress-related neurodegenerative disease. -- Highlights: ► Chlorpyrifos induces apoptosis. ► Chlorpyrifos inhibits mitochondrial complex I activity. ► ROS is involved in chlorpyrifos-induced apoptosis. ► Chlorpyrifos affects cellular antioxidant systems. ► Chlorpyrifos-induced apoptosis mediates activation of MAPK.

  1. Expression of apoptosis-regulating genes in the rat prostate following botulinum toxin type a injection

    Directory of Open Access Journals (Sweden)

    Gorgal Tiago

    2012-01-01

    Full Text Available Abstract Background Onabotulinumtoxin A (OnabotA injection has been investigated as a novel treatment for benign prostatic enlargement caused by benign prostatic hyperplasia. An OnabotA - induced volume reduction caused by sympathetic fibers impairment has been proposed as a potential mechanism of action. Our aim was to investigate the expression of apoptosis-regulating proteins in the rat prostate following OnabotA intraprostatic injection. Methods Adult Wistar rats were injected in the ventral lobes of the prostate with 10 U of OnabotA or saline. A set of OnabotA-injected animals was further treated with 0.5 mg/kg of phenylephrine (PHE subcutaneously daily. All animals were sacrificed after 1 week and had their prostates harvested. Immunohistochemical staining was performed for Bax, Bcl-xL and caspase-3 proteins and visualized by the avidin-biotin method. The optical density of the glandular cells was also determined, with measurement of differences between average optical densities for each group. Results Saline-treated animals showed intense epithelial staining for Bcl-xL and a faint labelling for both Bax and Caspase-3. OnabotA-treated rats showed a reduced epithelial staining of Bcl-xL and a consistently increased Bax and Caspase-3 staining when compared with saline-treated animals. PHE-treated animals showed a stronger Bcl-xL staining and reduced staining of both Bax and Caspase-3 when compared to the OnabotA group. Mean signal intensity measurements for each immunoreaction confirmed a significant decrease of the signal intensity for Bcl-xL and a significant increase of the signal intensity for Bax and Caspase 3 in OnabotA-injected animals when compared with the control group. In OnabotA+PHE treated animals mean signal intensity for Bcl-xL, Bax and Caspase 3 immunoreactions was identical to that of the control animals. Conclusions These results support the hypothesis that OnabotA activates apoptotic pathways in the rat prostate through a

  2. Inhibitor of apoptosis signal-regulating kinase 1 protects against acetaminophen-induced liver injury

    Energy Technology Data Exchange (ETDEWEB)

    Xie, Yuchao; Ramachandran, Anup [Department of Pharmacology, Toxicology, and Therapeutics, University of Kansas Medical Center, Kansas City, KS (United States); Breckenridge, David G.; Liles, John T. [Department of Biology, Gilead Sciences, Inc., Foster City, CA (United States); Lebofsky, Margitta [Department of Pharmacology, Toxicology, and Therapeutics, University of Kansas Medical Center, Kansas City, KS (United States); Farhood, Anwar [Department of Pathology, St. David' s North Austin Medical Center, Austin, TX 78756 (United States); Jaeschke, Hartmut, E-mail: hjaeschke@kumc.edu [Department of Pharmacology, Toxicology, and Therapeutics, University of Kansas Medical Center, Kansas City, KS (United States)

    2015-07-01

    Metabolic activation and oxidant stress are key events in the pathophysiology of acetaminophen (APAP) hepatotoxicity. The initial mitochondrial oxidative stress triggered by protein adduct formation is amplified by c-jun-N-terminal kinase (JNK), resulting in mitochondrial dysfunction and ultimately cell necrosis. Apoptosis signal-regulating kinase 1 (ASK1) is considered the link between oxidant stress and JNK activation. The objective of the current study was to assess the efficacy and mechanism of action of the small-molecule ASK1 inhibitor GS-459679 in a murine model of APAP hepatotoxicity. APAP (300 mg/kg) caused extensive glutathione depletion, JNK activation and translocation to the mitochondria, oxidant stress and liver injury as indicated by plasma ALT activities and area of necrosis over a 24 h observation period. Pretreatment with 30 mg/kg of GS-459679 almost completely prevented JNK activation, oxidant stress and injury without affecting the metabolic activation of APAP. To evaluate the therapeutic potential of GS-459679, mice were treated with APAP and then with the inhibitor. Given 1.5 h after APAP, GS-459679 was still protective, which was paralleled by reduced JNK activation and p-JNK translocation to mitochondria. However, GS-459679 treatment was not more effective than N-acetylcysteine, and the combination of GS-459679 and N-acetylcysteine exhibited similar efficacy as N-acetylcysteine monotherapy, suggesting that GS-459769 and N-acetylcysteine affect the same pathway. Importantly, inhibition of ASK1 did not impair liver regeneration as indicated by PCNA staining. In conclusion, the ASK1 inhibitor GS-459679 protected against APAP toxicity by attenuating JNK activation and oxidant stress in mice and may have therapeutic potential for APAP overdose patients. - Highlights: • Two ASK1 inhibitors protected against acetaminophen-induced liver injury. • The ASK1 inhibitors protect when used as pre- or post-treatment. • Protection by ASK1 inhibitor is

  3. Small kinetochore associated protein (SKAP promotes UV-induced cell apoptosis through negatively regulating pre-mRNA processing factor 19 (Prp19.

    Directory of Open Access Journals (Sweden)

    Shan Lu

    Full Text Available Apoptosis is a regulated cellular suicide program that is critical for the development and maintenance of healthy tissues. Previous studies have shown that small kinetochore associated protein (SKAP cooperates with kinetochore and mitotic spindle proteins to regulate mitosis. However, the role of SKAP in apoptosis has not been investigated. We have identified a new interaction involving SKAP, and we propose a mechanism through which SKAP regulates cell apoptosis. Our experiments demonstrate that both overexpression and knockdown of SKAP sensitize cells to UV-induced apoptosis. Further study has revealed that SKAP interacts with Pre-mRNA processing Factor 19 (Prp19. We find that UV-induced apoptosis can be inhibited by ectopic expression of Prp19, whereas silencing Prp19 has the opposite effect. Additionally, SKAP negatively regulates the protein levels of Prp19, whereas Prp19 does not alter SKAP expression. Finally, rescue experiments demonstrate that the pro-apoptotic role of SKAP is executed through Prp19. Taken together, these findings suggest that SKAP promotes UV-induced cell apoptosis by negatively regulating the anti-apoptotic protein Prp19.

  4. Aryl hydrocarbon receptor-dependent regulation of miR-196a expression controls lung fibroblast apoptosis but not proliferation

    Energy Technology Data Exchange (ETDEWEB)

    Hecht, Emelia [Department of Medicine, McGill University, Montreal, Quebec (Canada); Zago, Michela [Research Institute of the McGill University Health Centre, McGill University, Montreal, Quebec (Canada); Sarill, Miles [Department of Medicine, McGill University, Montreal, Quebec (Canada); Rico de Souza, Angela [Research Institute of the McGill University Health Centre, McGill University, Montreal, Quebec (Canada); Gomez, Alvin; Matthews, Jason [Department of Pharmacology and Toxicology, University of Toronto, Toronto, ON (Canada); Hamid, Qutayba; Eidelman, David H. [Department of Medicine, McGill University, Montreal, Quebec (Canada); Research Institute of the McGill University Health Centre, McGill University, Montreal, Quebec (Canada); Baglole, Carolyn J., E-mail: Carolyn.baglole@McGill.ca [Department of Medicine, McGill University, Montreal, Quebec (Canada); Research Institute of the McGill University Health Centre, McGill University, Montreal, Quebec (Canada)

    2014-11-01

    The aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor implicated in the regulation of apoptosis and proliferation. Although activation of the AhR by xenobiotics such as dioxin inhibits the cell cycle and control apoptosis, paradoxically, AhR expression also promotes cell proliferation and survival independent of exogenous ligands. The microRNA (miRNA) miR-196a has also emerged as a regulator of proliferation and apoptosis but a relationship between the AhR and miR-196a is not known. Therefore, we hypothesized that AhR-dependent regulation of endogenous miR-196a expression would promote cell survival and proliferation. Utilizing lung fibroblasts from AhR deficient (AhR{sup −/−}) and wild-type (AhR{sup +/+}) mice, we show that there is ligand-independent regulation of miRNA, including low miR-196a in AhR{sup −/−} cells. Validation by qRT-PCR revealed a significant decrease in basal expression of miR-196a in AhR{sup −/−} compared to AhR{sup +/+} cells. Exposure to AhR agonists benzo[a]pyrene (B[a]P) and FICZ as well as AhR antagonist CH-223191 decreased miR-196a expression in AhR{sup +/+} fibroblasts concomitant with decreased AhR protein levels. There was increased proliferation only in AhR{sup +/+} lung fibroblasts in response to serum, corresponding to a decrease in p27{sup KIP1} protein, a cyclin-dependent kinase inhibitor. Increasing the cellular levels of miR-196a had no effect on proliferation or expression of p27{sup KIP1} in AhR{sup −/−} fibroblasts but attenuated cigarette smoke-induced apoptosis. This study provides the first evidence that AhR expression is essential for the physiological regulation of cellular miRNA levels- including miR-196a. Future experiments designed to elucidate the functional relationship between the AhR and miR-196a may delineate additional novel ligand-independent roles for the AhR. - Highlights: • The AhR controls proliferation and apoptosis in lung cells. • The AhR regulates the

  5. Sulforaphane reverses glucocorticoid-induced apoptosis in osteoblastic cells through regulation of the Nrf2 pathway

    Directory of Open Access Journals (Sweden)

    Lin H

    2014-07-01

    Full Text Available Hao Lin,1,* Bo Wei,1,* Guangsheng Li,1 Jinchang Zheng,1 Jiecong Sun,1 Jiaqi Chu,2 Rong Zeng,1 Yanru Niu21Department of Spinal Surgery, Affiliated Hospital of Guangdong Medical College, Zhanjiang, People’s Republic of China; 2Laboratory Institute of Minimally Invasive Orthopedic Surgery, Affiliated Hospital of Guangdong Medical College, Zhanjiang, People’s Republic of China *These authors contributed equally to this work Abstract: Apoptosis of osteoblasts triggered by high-dose glucocorticoids (GCs has been identified as a major cause of osteoporosis. However, the underlying molecular mechanisms accounting for this action remain elusive, which has impeded the prevention and cure of this side effect. Sulforaphane (SFP is a naturally occurring isothiocyanate that has huge health benefits for humans. In this study, by using osteoblastic MC3T3-E1 cells as a model, we demonstrate the protective effects of SFP against dexamethasone (Dex-induced apoptosis and elucidate the underlying molecular mechanisms. The results show that SFP could effectively inhibit the Dex-induced growth inhibition and release of lactate dehydrogenase in MC3T3-E1 cells. Treatment with Dex induced caspase-dependent apoptosis in MC3T3-E1 cells, as evidenced by an increase in the Sub-G1 phase, chromatin condensation, and deoxyribonucleic acid fragmentation, which were significantly suppressed by coincubation with SFP. Mitochondria-mediated apoptosis pathway contributed importantly to Dex-induced apoptosis, as revealed by the activation of caspase-3/-9 and subsequent cleavage of poly adenosine diphosphate ribose polymerase, which was also effectively blocked by SFP. Moreover, treatments of Dex strongly induced overproduction of reactive oxygen species and inhibited the expression of nuclear factor erythroid 2-related factor 2 (Nrf2 and the downstream effectors HO1 and NQO1. However, cotreatment with SFP effectively reversed this action of Dex. Furthermore, silencing of Nrf2 by

  6. The Magea gene cluster regulates male germ cell apoptosis without affecting the fertility in mice

    Science.gov (United States)

    Hou, Siyuan; Xian, Li; Shi, Peiliang; Li, Chaojun; Lin, Zhaoyu; Gao, Xiang

    2016-01-01

    While apoptosis is essential for male germ cell development, improper activation of apoptosis in the testis can affect spermatogenesis and cause reproduction defects. Members of the MAGE-A (melanoma antigen family A) gene family are frequently clustered in mammalian genomes and are exclusively expressed in the testes of normal animals but abnormally activated in a wide variety of cancers. We investigated the potential roles of these genes in spermatogenesis by generating a mouse model with a 210-kb genomic deletion encompassing six members of the Magea gene cluster (Magea1, Magea2, Magea3, Magea5, Magea6 and Magea8). Male mice carrying the deletion displayed smaller testes from 2 months old with a marked increase in apoptotic germ cells in the first wave of spermatogenesis. Furthermore, we found that Magea genes prevented stress-induced spermatogenic apoptosis after N-ethyl-N-nitrosourea (ENU) treatment during the adult stage. Mechanistically, deletion of the Magea gene cluster resulted in a dramatic increase in apoptotic germ cells, predominantly spermatocytes, with activation of p53 and induction of Bax in the testes. These observations demonstrate that the Magea genes are crucial in maintaining normal testicular size and protecting germ cells from excessive apoptosis under genotoxic stress. PMID:27226137

  7. The Magea gene cluster regulates male germ cell apoptosis without affecting the fertility in mice.

    Science.gov (United States)

    Hou, Siyuan; Xian, Li; Shi, Peiliang; Li, Chaojun; Lin, Zhaoyu; Gao, Xiang

    2016-01-01

    While apoptosis is essential for male germ cell development, improper activation of apoptosis in the testis can affect spermatogenesis and cause reproduction defects. Members of the MAGE-A (melanoma antigen family A) gene family are frequently clustered in mammalian genomes and are exclusively expressed in the testes of normal animals but abnormally activated in a wide variety of cancers. We investigated the potential roles of these genes in spermatogenesis by generating a mouse model with a 210-kb genomic deletion encompassing six members of the Magea gene cluster (Magea1, Magea2, Magea3, Magea5, Magea6 and Magea8). Male mice carrying the deletion displayed smaller testes from 2 months old with a marked increase in apoptotic germ cells in the first wave of spermatogenesis. Furthermore, we found that Magea genes prevented stress-induced spermatogenic apoptosis after N-ethyl-N-nitrosourea (ENU) treatment during the adult stage. Mechanistically, deletion of the Magea gene cluster resulted in a dramatic increase in apoptotic germ cells, predominantly spermatocytes, with activation of p53 and induction of Bax in the testes. These observations demonstrate that the Magea genes are crucial in maintaining normal testicular size and protecting germ cells from excessive apoptosis under genotoxic stress. PMID:27226137

  8. Leishmania donovani: intracellular ATP level regulates apoptosis-like death in luteolin induced dyskinetoplastid cells.

    Science.gov (United States)

    Sen, Nilkantha; Das, Benu Brata; Ganguly, Agneyo; Banerjee, Bijoylaxhmi; Sen, Tanusree; Majumder, Hemanta K

    2006-11-01

    Leishmaniasis presents a spectrum of diseases ranging from benign cutaneous lesions to the often-fatal visceralizing form. Luteolin, a dietary flavone induces apoptosis-like death in both promastigote and amastigote forms of Leishmania, the causative agent of the diseases. Here, we have elucidated the mechanism of action of luteolin by analyzing the mitochondrial and cytosolic changes associated with apoptosis-like death of leishmanial cells. In Leishmania donovani, treatment with luteolin induces the loss of both maxicircles and minicircles which resulted in the formation of dyskinetoplastid cells. The loss of mitochondrial DNA causes reduction in the activities of complex I, II, III, and IV of electron transport chain. However, the mitochondrial ATPase activity of complex V remains almost unaltered during treatment with luteolin but the sensitivity to oligomycin is lost. The inactivation of ETC complex is associated with decrease in mitochondrial as well as glycolytic ATP production, which is responsible for depolarization of Deltapsi(m) and alteration in mitochondrial structure. This event is followed by the release of cytochrome c from mitochondria in mt-DNA depleted leishmanial cells and causes an activation of caspase like proteases. Collectively our results provide the first insight into the mechanistic pathway of apoptosis-like death where inhibition of glycolytic ATP production is an essential event responsible for depolarization of Deltapsi(m) in mt-DNA depleted cells to propagate apoptosis-like death in leishmanial cells. PMID:16707127

  9. Cypermethrin Induces Macrophages Death through Cell Cycle Arrest and Oxidative Stress-Mediated JNK/ERK Signaling Regulated Apoptosis

    Directory of Open Access Journals (Sweden)

    Fang Huang

    2016-06-01

    Full Text Available Cypermethrin is one of the most highly effective synthetic pyrethroid insecticides. The toxicity of cypermethrin to the reproductive and nervous systems has been well studied. However, little is known about the toxic effect of cypermethrin on immune cells such as macrophages. Here, we investigated the cytotoxicity of cypermethrin on macrophages and the underlying molecular mechanisms. We found that cypermethrin reduced cell viability and induced apoptosis in RAW 264.7 cells. Cypermethrin also increased reactive oxygen species (ROS production and DNA damage in a dose-dependent manner. Moreover, cypermethrin-induced G1 cell cycle arrest was associated with an enhanced expression of p21, wild-type p53, and down-regulation of cyclin D1, cyclin E and CDK4. In addition, cypermethrin treatment activated MAPK signal pathways by inducing c-Jun N-terminal kinase (JNK and extracellular regulated protein kinases 1/2 ERK1/2 phosphorylation, and increased the cleaved poly ADP-ribose polymerase (PARP. Further, pretreatment with antioxidant N-acetylcysteine (NAC effectively abrogated cypermethrin-induced cell cytotoxicity, G1 cell cycle arrest, DNA damage, PARP activity, and JNK and ERK1/2 activation. The specific JNK inhibitor (SP600125 and ERK1/2 inhibitor (PD98059 effectively reversed the phosphorylation level of JNK and ERK1/2, and attenuated the apoptosis. Taken together, these data suggested that cypermethrin caused immune cell death via inducing cell cycle arrest and apoptosis regulated by ROS-mediated JNK/ERK pathway.

  10. Estrogen protects neuronal cells from amyloid beta-induced apoptosis via regulation of mitochondrial proteins and function

    Directory of Open Access Journals (Sweden)

    Iwamoto Sean

    2006-11-01

    Full Text Available Abstract Background Neurodegeneration in Alzheimer's disease is associated with increased apoptosis and parallels increased levels of amyloid beta, which can induce neuronal apoptosis. Estrogen exposure prior to neurotoxic insult of hippocampal neurons promotes neuronal defence and survival against neurodegenerative insults including amyloid beta. Although all underlying molecular mechanisms of amyloid beta neurotoxicity remain undetermined, mitochondrial dysfunction, including altered calcium homeostasis and Bcl-2 expression, are involved in neurodegenerative vulnerability. Results In this study, we investigated the mechanism of 17β-estradiol-induced prevention of amyloid beta-induced apoptosis of rat hippocampal neuronal cultures. Estradiol treatment prior to amyloid beta exposure significantly reduced the number of apoptotic neurons and the associated rise in resting intracellular calcium levels. Amyloid beta exposure provoked down regulation of a key antiapoptotic protein, Bcl-2, and resulted in mitochondrial translocation of Bax, a protein known to promote cell death, and subsequent release of cytochrome c. E2 pretreatment inhibited the amyloid beta-induced decrease in Bcl-2 expression, translocation of Bax to the mitochondria and subsequent release of cytochrome c. Further implicating the mitochondria as a target of estradiol action, in vivo estradiol treatment enhanced the respiratory function of whole brain mitochondria. In addition, estradiol pretreatment protected isolated mitochondria against calcium-induced loss of respiratory function. Conclusion Therefore, we propose that estradiol pretreatment protects against amyloid beta neurotoxicity by limiting mitochondrial dysfunction via activation of antiapoptotic mechanisms.

  11. Electroacupuncture Regulates Apoptosis/Proliferation of Intramuscular Interstitial Cells of Cajal and Restores Colonic Motility in Diabetic Constipation Rats

    Directory of Open Access Journals (Sweden)

    Juanjuan Xu

    2013-01-01

    Full Text Available Injury of interstitial cells of Cajal (ICC is associated with gut dysmotility in diabetic rats. We have shown an acceleration of the colonic contractility by electroacupuncture stimulation (EAS. However, little is known about potential roles of EAS on colonic transit and ICC. In this study, we evaluate the effect of EAS on colonic transit and investigate whether apoptosis/proliferation of ICC was involved in regulative effect of EAS on colonic transit. Rats were randomly assigned to normal, diabetic, diabetic-plus-sham stimulation, diabetic-plus-low-frequency stimulation, and diabetic-plus-high-frequency stimulation groups. Bead expulsion test was used for measuring the distal colonic transit. The Kit (ICC marker was detected by western blot. Apoptotic ICC was detected by terminal dUTP nucleotide end labeling. Proliferating ICC was identified by Kit/Ki67 double immunofluorescent staining on whole mount preparations. Ultrastructure changes of ICC were studied using electron microscopy. Results showed that high-frequency stimulation significantly promoted colonic transit. Low- and high-frequency stimulation markedly rescued intramuscular ICC from apoptosis. Abundant proliferating intramuscular ICC was found in low- and high-frequency stimulation groups. Our results indicate that high-frequency EAS has stimulatory effect on the distal colonic transit, which may be mediated by downregulation of the apoptosis and upregulation of the proliferation of intramuscular ICC.

  12. HERBAL MEDICINE 960 RECIPE REGULATES THE PROLIFERATION AND APOPTOSIS OF HUMAN HEPATOMA CELL LINE SMMC-7721 CELLS

    Institute of Scientific and Technical Information of China (English)

    王昌俊; 李建军; 陈庆强; 陈伟; 钱伯文

    2001-01-01

    To investigate the mechanism of 960 recipe regulating the proliferation and apoptosis of human hepatoma SMMC7721 cells.Methods 960 recipe-containing serum was derived from rats that pre-treated with 960 recipe through gastrogavage, and was added to cultured human hepatoma SMMC-7721 cells while the normal rat serum was tested as control. Cell proliferation was measured with 3H-TdR incorporation. Cell morphology was tested by acridine orange staining. Cell apoptosis and expressions of p53, bcl-2 and p21ras gene protein were analyzed with flow cytometry.Results After treating with 960 recipe, the inhibitory rate of 3H-TdR was 42.2% for 48h. Cell morphology showed typical apoptotic cells with condensed and fragmented nuclei. There were typical apoptotic peaks in DNA histogram, the apoptotic rate being 21.25% and 27.77% for 24h, 48h respectively. Cell cycle analysis showed that cells were arrested at S-phase by treating with 960 recipe for 24h and at G0/G1 phase for 48h. The expression of p53 increased, but bcl-2 and ras were reduced by treating with 960 recipe for 24h.Conclusion 960 recipe can inhibit proliferation and induce apoptosis of human hepatoma cells, and affect the cell cycle, the expression of oncogene and tumor suppressor gene. These might be the main antihepatoma mechanisms of 960 recipe.

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

    Directory of Open Access Journals (Sweden)

    Tao Zhang

    2015-10-01

    -associated endothelial cell apoptosis may result from down regulation of Bcl-2, through increased miR-429 that binds and suppresses translation of Bcl-2 mRNA.

  14. Protein phosphatase 1α is a Ras-activated Bad phosphatase that regulates interleukin-2 deprivation-induced apoptosis

    Science.gov (United States)

    Ayllón, Verónica; Martínez-A, Carlos; García, Alphonse; Cayla, Xavier; Rebollo, Angelita

    2000-01-01

    Growth factor deprivation is a physiological mechanism to regulate cell death. We utilize an interleukin-2 (IL-2)-dependent murine T-cell line to identify proteins that interact with Bad upon IL-2 stimulation or deprivation. Using the yeast two-hybrid system, glutathione S-transferase (GST) fusion proteins and co-immunoprecipitation techniques, we found that Bad interacts with protein phosphatase 1α (PP1α). Serine phosphorylation of Bad is induced by IL-2 and its dephosphorylation correlates with appearance of apoptosis. IL-2 deprivation induces Bad dephosphorylation, suggesting the involvement of a serine phosphatase. A serine/threonine phosphatase activity, sensitive to the phosphatase inhibitor okadaic acid, was detected in Bad immunoprecipitates from IL-2-stimulated cells, increasing after IL-2 deprivation. This enzymatic activity also dephosphorylates in vivo 32P-labeled Bad. Treatment of cells with okadaic acid blocks Bad dephosphorylation and prevents cell death. Finally, Ras activation controls the catalytic activity of PP1α. These results strongly suggest that Bad is an in vitro and in vivo substrate for PP1α phosphatase and that IL-2 deprivation-induced apoptosis may operate by regulating Bad phosphorylation through PP1α phosphatase, whose enzymatic activity is regulated by Ras. PMID:10811615

  15. LncRNA-uc.167 influences cell proliferation, apoptosis and differentiation of P19 cells by regulating Mef2c.

    Science.gov (United States)

    Song, Guixian; Shen, Yahui; Ruan, Zhongbao; Li, Xing; Chen, Yumei; Yuan, Wei; Ding, Xiangwei; Zhu, Li; Qian, Lingmei

    2016-09-15

    In our previous study we screened thousands of lncRNAs for their relationship with ventricular septal defect. Among these lncRNAs, uc.167 attracted our attention for its high level of conservation and that it was antisense to the Mef2c gene, which encodes myocyte enhancer factor 2C. This study aims to investigate the role of uc.167 during cardiomyocyte maturation in P19 cells induction and possible mechanism. The uc.167 expression level in human heart tissue of ventricular septum defect (VSD) was evaluated by qRT-PCR. The UCSC database was searched to investigate the bioinformatics of uc.167. We constructed overexpression vector of uc.167 and Mef2c. To detect proliferation and apoptosis, we combined cell cycle analysis and CCK8, Hoechst staining, flow cytometry and caspase-3 assays, respectively. The cardiomyogenesis related RNAs (cTnT, GATA4, and Mef2c) and proteins were detected by qRT-PCR and Western blotting. In this study, we found that uc.167 expression was significantly increased in VSD heart tissues. uc.167 is on the opposite strand to the coding gene Mef2c. The expression model of Mef2c and uc.167 showed an opposite correlation in the embryonic development and process of differentiation of P19 cells into cardiomyocytes. Overexpression of uc.167 inhibited proliferation but promoted apoptosis in P19 cells compared with the vector group, and those relative mRNAs and proteins decreased during the differentiation process. Whereas, co-expression of Mef2c and uc.167 can partially reverse the negative effects of uc.167 on proliferation, apoptosis and differentiation. Taken together, our findings suggest that uc.167 contributes to the development potential of VSD and may constitute a potential therapeutic target in this disease. uc.167 influences cell proliferation, apoptosis and differentiation of P19 cell by regulating Mef2c. PMID:27268728

  16. Down regulation of miR-203 in radiation-induced thymic lymphoma promoted cells proliferation and inhibited apoptosis%Down regulation of miR-203in radiation-induced thymic lymphoma promoted cells proliferation and inhibited apoptosis

    Institute of Scientific and Technical Information of China (English)

    Zhang Chaoxiong; Zhang Mingjian; Gao Fu; Zhou Chuanfeng; Zhang Pei; Cai Jianming; Liu Cong

    2015-01-01

    Objective To investigate the role of miR-203 in radiation-induced thymic lymphoma (RITL).Methods A 60Co irradiator was used for total-body irradiation.MicroRNAs(miRNAs) level was assayed by qRT-PCR.Cell proliferation was assayed by MTT assay.Cell apoptosis was examined by fluorescence activated cell sorter (FACS).Dual luciferase reporter assay system was used to detect the 3'UTR reporter.Results MiR-203 was down-regulated in RITL tissues.Overexpression of miR-203 strongly inhibited the proliferation of both NIH3T3 cells and EL4 cells and vice versa.MiR-203 inhibited cells proliferation and induced apoptosis via TANK-binding kinase (TBK1),SLUG (SNAI2) and Cyclin D1 (CCND1).Conclusions Radiation down-regulated the level of miR-203 in thymic,which promoted radiation-induced thymic lymphoma by targeting TBK1,SNAI2 and CCND1.

  17. PRAS40 and PRR5-like protein are new mTOR interactors that regulate apoptosis.

    Directory of Open Access Journals (Sweden)

    Kathrin Thedieck

    Full Text Available TOR (Target of Rapamycin is a highly conserved protein kinase and a central controller of cell growth. TOR is found in two functionally and structurally distinct multiprotein complexes termed TOR complex 1 (TORC1 and TOR complex 2 (TORC2. In the present study, we developed a two-dimensional liquid chromatography tandem mass spectrometry (2D LC-MS/MS based proteomic strategy to identify new mammalian TOR (mTOR binding proteins. We report the identification of Proline-rich Akt substrate (PRAS40 and the hypothetical protein Q6MZQ0/FLJ14213/CAE45978 as new mTOR binding proteins. PRAS40 binds mTORC1 via Raptor, and is an mTOR phosphorylation substrate. PRAS40 inhibits mTORC1 autophosphorylation and mTORC1 kinase activity toward eIF-4E binding protein (4E-BP and PRAS40 itself. HeLa cells in which PRAS40 was knocked down were protected against induction of apoptosis by TNFalpha and cycloheximide. Rapamycin failed to mimic the pro-apoptotic effect of PRAS40, suggesting that PRAS40 mediates apoptosis independently of its inhibitory effect on mTORC1. Q6MZQ0 is structurally similar to proline rich protein 5 (PRR5 and was therefore named PRR5-Like (PRR5L. PRR5L binds specifically to mTORC2, via Rictor and/or SIN1. Unlike other mTORC2 members, PRR5L is not required for mTORC2 integrity or kinase activity, but dissociates from mTORC2 upon knock down of tuberous sclerosis complex 1 (TSC1 and TSC2. Hyperactivation of mTOR by TSC1/2 knock down enhanced apoptosis whereas PRR5L knock down reduced apoptosis. PRR5L knock down reduced apoptosis also in mTORC2 deficient cells. The above suggests that mTORC2-dissociated PRR5L may promote apoptosis when mTOR is hyperactive. Thus, PRAS40 and PRR5L are novel mTOR-associated proteins that control the balance between cell growth and cell death.

  18. Increased expression of 78 kD glucose-regulated protein promotes cardiomyocyte apoptosis in a rat model of liver cirrhosis

    OpenAIRE

    Zhang, Lili; Zhang, Huiying; Lv, Minli; Jia, Jiantao; Fan, Yimin; Tian, Xiaoxia; Li, Xujiong; Li, Baohong; Ji, Jingquan; Wang, Limin; Zhao, Zhongfu; Han, Dewu; Ji, Cheng

    2015-01-01

    Aims: This study was to investigate the role and underlying mechanism of 78 kD glucose-regulated protein (GRP78) in cardiomyocyte apoptosis in a rat model of liver cirrhosis. Methods: A rat model of liver cirrhosis was established with multiple pathogenic factors. A total of 42 male SD rats were randomly divided into the liver cirrhosis group and control group. Cardiac structure analysis was performed to assess alterations in cardiac structure. Cardiomyocytes apoptosis was detected by TdT-med...

  19. Regulation of HSP27 on NF-κB pathway activation may be involved in metastatic hepatocellular carcinoma cells apoptosis

    International Nuclear Information System (INIS)

    During the process of metastasis, cells are subjected to various apoptotic stimuli. Aberrant expression of apoptotic regulators often contribute to cell metastasis. Heat shock protein 27(HSP27) is confirmed as an apoptosis regulator, but its antiapoptotic mechanism in metastatic hepatocellular carcinoma (HCC) cells remains unclear. Levels of HSP27 protein and its phosphorylation in Hep3B, MHCC97L to MHCC97H cells with different metastatic potentials were determined by western blot analysis. MHCC97H cells were transfected with specific small interference RNA (siRNA) against HSP27. The in vitro migration and invasion potentials of cells were evaluated by Transwell assay. The apoptosis ratio of MHCC97H cells was analyzed by TUNEL staining and Flow Cytometry. Alteration of signal transduction pathway after HSP27 knockdown in MHCC97H cells was evaluated through a Human Q Series Signal Transduction in Cancer Gene Array analysis. Nuclear NF-κB contentration and endogenous IKK activity were demonstrated by ELISA assay. The association of IKKα, IKKβ, IκBα with HSP27 and the association between IKKβ and IKKα in MHCC97H cells were determined by co-immunoprecipitation assay followed by western blot analysis. HSP27 protein and its phosphorylation increased in parallel with enhanced metastatic potentials of HCC cells. siRNA-mediated HSP27 knockdown in MHCC97H significantly suppressed cells migration and invasion in vitro and induced cell apoptosis; the prominently altered signal transduction pathway was NF-κB pathway after HSP27 knockdown in MHCC97H cells. Furthermore, inhibition of HSP27 expression led to a significant decrease of nuclear NF-κB contentration and endogenous IKK activity. In addition, HSP27 was associated with IKKα, IKKβ, IκBα in three HCC cells above. ELISA assay and western blot analysis also showed a decrease of the association between IKKβ and IKKα, the association between phosphor-HSP27 and IKK complex, and an increase of total IκBα but

  20. HPV16 E2 could act as down-regulator in cellular genes implicated in apoptosis, proliferation and cell differentiation

    Directory of Open Access Journals (Sweden)

    Valencia-Hernández Armando

    2011-05-01

    Full Text Available Abstract Background Human Papillomavirus (HPV E2 plays several important roles in the viral cycle, including the transcriptional regulation of the oncogenes E6 and E7, the regulation of the viral genome replication by its association with E1 helicase and participates in the viral genome segregation during mitosis by its association with the cellular protein Brd4. It has been shown that E2 protein can regulate negative or positively the activity of several cellular promoters, although the precise mechanism of this regulation is uncertain. In this work we constructed a recombinant adenoviral vector to overexpress HPV16 E2 and evaluated the global pattern of biological processes regulated by E2 using microarrays expression analysis. Results The gene expression profile was strongly modified in cells expressing HPV16 E2, finding 1048 down-regulated genes, and 581 up-regulated. The main cellular pathway modified was WNT since we found 28 genes down-regulated and 15 up-regulated. Interestingly, this pathway is a convergence point for regulating the expression of genes involved in several cellular processes, including apoptosis, proliferation and cell differentiation; MYCN, JAG1 and MAPK13 genes were selected to validate by RT-qPCR the microarray data as these genes in an altered level of expression, modify very important cellular processes. Additionally, we found that a large number of genes from pathways such as PDGF, angiogenesis and cytokines and chemokines mediated inflammation, were also modified in their expression. Conclusions Our results demonstrate that HPV16 E2 has regulatory effects on cellular gene expression in HPV negative cells, independent of the other HPV proteins, and the gene profile observed indicates that these effects could be mediated by interactions with cellular proteins. The cellular processes affected suggest that E2 expression leads to the cells in to a convenient environment for a replicative cycle of the virus.

  1. KLF6 and iNOS regulates apoptosis during respiratory syncytial virus infection

    OpenAIRE

    Mgbemena, Victoria; Segovia, Jesus; Chang, Te-Hung; Bose, Santanu

    2013-01-01

    Human respiratory syncytial virus (RSV) is a highly pathogenic lung-tropic virus that causes severe respiratory diseases. Enzymatic activity of inducible nitric oxide (iNOS) is required for NO generation. Although NO contributes to exaggerated lung disease during RSV infection, the role of NO in apoptosis during infection is not known. In addition, host trans-activator(s) required for iNOS gene expression during RSV infection is unknown. In the current study we have uncovered the mechanism of...

  2. Curcumin regulates hepatoma cell proliferation and apoptosis through the Notch signaling pathway

    OpenAIRE

    Liu, Zheng-cai; Yang, Zhao-Xu; Zhou, Jing-Shi; Zhang, Hong-Tao; Huang, Qi-Ke; Dang, Li-Li; Liu, Guang-Xin; Tao, Kai-shan

    2014-01-01

    Curcumin has become a compound of interest for its antioxidant and anti-neoplastic properties. This study sought to determine the effect of curcumin administration on cell proliferation and apoptosis in hepatoma cells. SMMC-7721 hepatoma cells were treated with 10, 30, or 90 μM curcumin solution, with DMEM alone (negative control), or with 20 mg/L fluorouracil (positive control). MTT colorimetry detected significant differences in the rates of cell proliferation inhibition following curcumin ...

  3. FLIP the Switch: Regulation of Apoptosis and Necroptosis by cFLIP

    OpenAIRE

    Yuichi Tsuchiya; Osamu Nakabayashi; Hiroyasu Nakano

    2015-01-01

    cFLIP (cellular FLICE-like inhibitory protein) is structurally related to caspase-8 but lacks proteolytic activity due to multiple amino acid substitutions of catalytically important residues. cFLIP protein is evolutionarily conserved and expressed as three functionally different isoforms in humans (cFLIPL, cFLIPS, and cFLIPR). cFLIP controls not only the classical death receptor-mediated extrinsic apoptosis pathway, but also the non-conventional pattern recognition receptor-dependent apoptot...

  4. Apoptosis regulates ipRGC spacing necessary for rods and cones to drive circadian photoentrainment

    OpenAIRE

    Chen, Shih-Kuo; Chew, Kylie S.; McNeill, David S.; Keeley, Patrick W.; Ecker, Jennifer L.; Mao, Buqing Q.; Pahlberg, Johan; Kim, Bright; Lee, Sammy C. S.; Fox, Michael; Guido, William; Wong, Kwoon Y.; Sampath, Alapakkam P.; Reese, Benjamin E.; Kuruvilla, Rejji

    2013-01-01

    The retina consists of ordered arrays of individual types of neurons for processing vision. Here we show that such order is necessary for intrinsically photosensitive retinal ganglion cells (ipRGCs) to function as irradiance detectors. We found that during development, ipRGCs undergo proximity-dependent Bax-mediated apoptosis. Bax mutant mice exhibit disrupted ipRGC spacing and dendritic stratification with an increase in abnormally localized synapses. ipRGCs are the sole conduit for light in...

  5. ADRB3 adrenergic receptor is a key regulator of human myometrial apoptosis and inflammation during chorioamnionitis.

    OpenAIRE

    Lirussi, Fréderic; Rakotoniaina, Zo; Madani, Siham; Goirand, Françoise; Breuiller-Fouché, Michelle; Leroy, Marie-Josèphe; Sagot, Paul; Morrison, John; Dumas, Monique; Bardou, Marc

    2008-01-01

    The pathophysiology underlying preterm labor triggered by inflammatory conditions such as chorioamnionitis remains largely unclear. It has already been suggested that beta-3 adrenergic (ADRB3) agonists might be of interest in the pharmacological management of preterm labor. Although there is evidence implicating ADRB receptors in the control of inflammation, there are minimal data relating specifically to ADRB3. To explore the cellular consequences of chorioamnionitis and detect apoptosis, we...

  6. Identification of proteins that regulate radiation-induced apoptosis in murine tumors with wild type p53

    International Nuclear Information System (INIS)

    In this study, we investigated the molecular factors determining the induction of apoptosis by radiation. Two murine tumors syngeneic to C3H/HeJ mice were used: an ovarian carcinoma OCa-I, and a hepatocarcinoma HCa-I. Both have wild type p53, but display distinctly different radiosensitivity in terms of specific growth delay (12.7 d in OCa-I and 0.3 d in HCa-I) and tumor cure dose 50% (52.6 Gy in OCa-I and >80 Gy in HCa-I). Eight-mm tumors on the thighs of mice were irradiated with 25 Gy and tumor samples were collected at regular time intervals after irradiation. The peak levels of apoptosis were 16.1±0.6% in OCa-I and 0.2±0.0% in HCa-I at 4 h after radiation, and this time point was used for subsequent proteomics analysis. Protein spots were identified by peptide mass fingerprinting with a focus on those related to apoptosis. In OCa-I tumors, radiation increased the expression of cytochrome c oxidase and Bcl2/adenovirus E1B-interacting 2 (Nip 2) protein higher than 3-fold. However in HCa-I, these two proteins showed no significant change. The results suggest that radiosensitivity in tumors with wild type p53 is regulated by a complex mechanism. Furthermore, these proteins could be molecular targets for a novel therapeutic strategy involving the regulation of radiosensitivity. (author)

  7. ACLY and ACC1 Regulate Hypoxia-Induced Apoptosis by Modulating ETV4 via α-ketoglutarate.

    Directory of Open Access Journals (Sweden)

    Melissa M Keenan

    2015-10-01

    Full Text Available In order to propagate a solid tumor, cancer cells must adapt to and survive under various tumor microenvironment (TME stresses, such as hypoxia or lactic acidosis. To systematically identify genes that modulate cancer cell survival under stresses, we performed genome-wide shRNA screens under hypoxia or lactic acidosis. We discovered that genetic depletion of acetyl-CoA carboxylase (ACACA or ACC1 or ATP citrate lyase (ACLY protected cancer cells from hypoxia-induced apoptosis. Additionally, the loss of ACLY or ACC1 reduced levels and activities of the oncogenic transcription factor ETV4. Silencing ETV4 also protected cells from hypoxia-induced apoptosis and led to remarkably similar transcriptional responses as with silenced ACLY or ACC1, including an anti-apoptotic program. Metabolomic analysis found that while α-ketoglutarate levels decrease under hypoxia in control cells, α-ketoglutarate is paradoxically increased under hypoxia when ACC1 or ACLY are depleted. Supplementation with α-ketoglutarate rescued the hypoxia-induced apoptosis and recapitulated the decreased expression and activity of ETV4, likely via an epigenetic mechanism. Therefore, ACC1 and ACLY regulate the levels of ETV4 under hypoxia via increased α-ketoglutarate. These results reveal that the ACC1/ACLY-α-ketoglutarate-ETV4 axis is a novel means by which metabolic states regulate transcriptional output for life vs. death decisions under hypoxia. Since many lipogenic inhibitors are under investigation as cancer therapeutics, our findings suggest that the use of these inhibitors will need to be carefully considered with respect to oncogenic drivers, tumor hypoxia, progression and dormancy. More broadly, our screen provides a framework for studying additional tumor cell stress-adaption mechanisms in the future.

  8. Down-regulation of microRNA-26b rescued hypoxia-induced apoptosis in cultured neonatal rat cardiac myocytes by regulating PTEN

    OpenAIRE

    Wang, Xiaoyu; Li, Chen; Dai, Qiaoqun

    2015-01-01

    Background: Cardiomyocyte hypoxia causes cardiac hypertrophy and other major myocardial injuries. We investigated the molecular mechanism of microRNA-26b (miR-26b) in regulating hypoxia-induced apoptosis in rat neonatal cardiomyocytes. Methods: Neonatal rat cardiomyocytes was prepared in vitro and hypoxia was induced. Apoptotic cardiomyocytes were examined by TUNEL staining and the expression of miR-26b were monitored by qRT-PCR. The effect of mir-26b downregulation on hypoxia-induced apoptos...

  9. Simulated microgravity induce apoptosis and down-regulation of erythropoietin receptor of UT-7/EPO cells

    Science.gov (United States)

    Zou, Li-xue; Cui, Shao-yan; Zhong, Jian; Yi, Zong-chun; Sun, Yan; Fan, Yu-bo; Zhuang, Feng-yuan

    2010-11-01

    Hematopoietic progenitor cell proliferation can be alternated on either spaceflight or under simulated microgravity experiments on the ground; however, the underlying mechanism remains largely unknown. In the present study, we have demonstrated that exposure of human erythropoietin (EPO)-dependent leukemia cell line UT-7/EPO cells to conditions of simulated microgravity with a rotary culture instrument significantly inhibited the cellular proliferation rate. Adding higher concentrations of EPO to the culture medium failed to improve the inhibitory status. Cell apoptosis was detected by fluorescence staining of cell nuclei and a flow cytometry assay using Annexin V/PI double staining. This microgravity-induced apoptosis in UT-7/EPO cells could be blocked by a pancaspase inhibitor Z-VAD-FMK. Immunoblotting demonstrated that rotary culture resulted in a reduction of the expression of Bcl-xL, an anti-apoptotic protein, and the cleavage of caspase-3. Furthermore, rotary culture reduced surface localization and protein content, as well as the mRNA expression of erythropoietin receptor (EPOR) of UT-7/EPO. Take together, the findings indicated that simulated microgravity may induce mitochondrial related apoptosis of UT-7/EPO cell through depressing the EPO-EPOR pathway.

  10. TRAP1 regulates cell cycle and apoptosis in thyroid carcinoma cells.

    Science.gov (United States)

    Palladino, Giuseppe; Notarangelo, Tiziana; Pannone, Giuseppe; Piscazzi, Annamaria; Lamacchia, Olga; Sisinni, Lorenza; Spagnoletti, Girolamo; Toti, Paolo; Santoro, Angela; Storto, Giovanni; Bufo, Pantaleo; Cignarelli, Mauro; Esposito, Franca; Landriscina, Matteo

    2016-09-01

    Tumor necrosis factor receptor-associated protein 1 (TRAP1) is a heat shock protein 90 (HSP90) molecular chaperone upregulated in several human malignancies and involved in protection from apoptosis and drug resistance, cell cycle progression, cell metabolism and quality control of specific client proteins. TRAP1 role in thyroid carcinoma (TC), still unaddressed at present, was investigated by analyzing its expression in a cohort of 86 human TCs and evaluating its involvement in cancer cell survival and proliferation in vitro Indeed, TRAP1 levels progressively increased from normal peritumoral thyroid gland, to papillary TCs (PTCs), follicular variants of PTCs (FV-PTCs) and poorly differentiated TCs (PDTCs). By contrast, anaplastic thyroid tumors exhibited a dual pattern, the majority being characterized by high TRAP1 levels, while a small subgroup completely negative. Consistently with a potential involvement of TRAP1 in thyroid carcinogenesis, TRAP1 silencing resulted in increased sensitivity to paclitaxel-induced apoptosis, inhibition of cell cycle progression and attenuation of ERK signaling. Noteworthy, the inhibition of TRAP1 ATPase activity by pharmacological agents resulted in attenuation of cell proliferation, inhibition of ERK signaling and reversion of drug resistance. These data suggest that TRAP1 inhibition may be regarded as potential strategy to target specific features of human TCs, i.e., cell proliferation and resistance to apoptosis. PMID:27422900

  11. Resveratrol inhibits β-amyloid-induced neuronal apoptosis through regulation of SIRT1-ROCK1 signaling pathway.

    Directory of Open Access Journals (Sweden)

    Xiaowen Feng

    Full Text Available Alzheimer's disease (AD is characterized by the accumulation of β-amyloid peptide (Aβ and loss of neurons. Recently, a growing body of evidences have indicated that as a herbal compound naturally derived from grapes, resveratrol modulates the pathophysiology of AD, however, with a largely unclear mechanism. Therefore, we aimed to investigate the protection of resveratrol against the neurotoxicity of β-amyloid peptide 25-35 (Aβ(25-35 and further explore its underlying mechanism in the present study. PC12 cells were injuried by Aβ(25-35, and resveratrol at different concentrations was added into the culture medium. We observed that resveratrol increased cell viability through the 3-(4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide (MTT and lactate dehydrogenase (LDH colorimetric assays. Flow cytometry indicated the reduction of cell apoptosis by resveratrol. Moreover, resveratrol also stabilized the intercellular Ca(2+ homeostasis and attenuated Aβ(25-35 neurotoxicity. Additionally, Aβ(25-35-suppressed silent information regulator 1 (SIRT1 activity was significantly reversed by resveratrol, resulting in the downregulation of Rho-associated kinase 1 (ROCK1. Our results clearly revealed that resveratrol significantly protected PC12 cells and inhibited the β-amyloid-induced cell apoptosis through the upregulation of SIRT1. Moreover, as a downstream signal molecule, ROCK1 was negatively regulated by SIRT1. Taken together, our study demonstrated that SIRT1-ROCK1 pathway played a critical role in the pathomechanism of AD.

  12. mad—overexpression down regulates the malignant growth and p53 mediated apoptosis in human hepatocellular carcinoma BEL—7404 cells

    Institute of Scientific and Technical Information of China (English)

    ZHANHUA; YONGHUAXU

    1999-01-01

    Mad protein has been shown as an antagonist of cMyc protein in some cell lines.The effect of Mad protein to the malignant phenotype of human hepatoma BEL-7404 cell line was investigated experimentally.An eukarryotic vector pCDNA Ⅲ containing full ORF fragment of mad cDNA was transfected into targeted cells.Under G418 selection,stable Mad-overexpressed cells were cloned.Studies on the effect of Mad over-expression in cell proliferation and cell cycle revealed that cell morphology of the Mad-overexpressed BEL-7404-M1 cells was significantly different from the parent and control vector transfected cells.DNA synthesis,cell proliferation and anchorage-independent growth in soft-agar of the madtransfected cells were partially inhibited in comparison to control cells.Flos cytometry analysis indicated that mad over-expression might block more transfectant cells at G0/G1 phase,resulting in the retardation of cell proliferation.RT-PCR detected a marked inhibition of the expression of cdc25A,an important regulator gene of G0/G1 to S phase in cell cycle.It was also found that Mad protein overexpression could greatly suppress p53-mediated apoptosis in BEL-74040M1 cells in the absence of serume.Thus,Mad proteins may function as a negative regulator antagonizing c-Myc activity in the control of cell growth and apoptosis in human hepatocellular carcinoma BEL-7404 cells.

  13. Cbl participates in shikonin-induced apoptosis by negatively regulating phosphoinositide 3-kinase/protein kinase B signaling.

    Science.gov (United States)

    Qu, Dan; Xu, Xiao-Man; Zhang, Meng; Jiang, Ting-Shu; Zhang, Yi; Li, Sheng-Qi

    2015-07-01

    Shikonin, a naturally occurring naphthoquinone, exhibits anti-tumorigenic activity. However, its precise mechanisms of action have remained elusive. In the present study, the involvement in the action of shikonin of the ubiquitin ligases Cbl-b and c-Cbl, which are negative regulators of phosphoinositide 3-kinase (PI3K) activation, was investigated. Shikonin was observed to reduce cell viability and induce apoptosis and G2/M phase arrest in lung cancer cells. In addition, shikonin increased the protein levels of B-cell lymphoma 2 (Bcl-2)-associated X and p53 and reduced those of Bcl-2. Additionally, shikonin inhibited PI3k/Akt activity and upregulated Cbl protein expression. In addition, a specific inhibitor of PI3K, LY294002, was observed to have a synergistic effect on the proliferation inhibition and apoptotic induction of A549 cells with shikonin. In conclusion, the results of the present study suggested that Cbl proteins promote shikonin-induced apoptosis by negatively regulating PI3K/Akt signaling in lung cancer cells.

  14. Down-regulation of msrb3 and destruction of normal auditory system development through hair cell apoptosis in zebrafish.

    Science.gov (United States)

    Shen, Xiaofang; Liu, Fei; Wang, Yingzhi; Wang, Huijun; Ma, Jing; Xia, Wenjun; Zhang, Jin; Jiang, Nan; Sun, Shaoyang; Wang, Xu; Ma, Duan

    2015-01-01

    Hearing defects can significantly influence quality of life for those who experience them. At this time, 177 deafness genes have been cloned, including 134 non-syndromic hearing-loss genes. The methionine sulfoxide reductase B3 (Ahmed et al., 2011) gene (also called DFNB74) is one such newly discovered hearing-loss gene. Within this gene c.265 T>G and c.55 T>C mutations are associated with autosomal recessive hearing loss. However, the biological role and mechanism underlying how it contributes to deafness is unclear. Thus, to better understand this mutation, we designed splicing morpholinos for the purpose of down-regulating msrb3 in zebrafish. Morphants exhibited small, tiny, fused, or misplaced otoliths and abnormal numbers of otoliths. Down-regulation of msrb3 also caused shorter, thinner, and more crowded cilia. Furthermore, L1-8 neuromasts were reduced and disordered in the lateral line system; hair cells in each neuromast underwent apoptosis. Co-injection with human MSRB3 mRNA partially rescued auditory system defects, but mutant MSRB3 mRNA could not. Thus, msrb3 is instrumental for auditory system development in zebrafish and MSRB3-related deafness may be caused by promotion of hair cell apoptosis.

  15. Reactive oxygen species effect PASMCs apoptosis via regulation of dynamin-related protein 1 in hypoxic pulmonary hypertension.

    Science.gov (United States)

    Zhang, Lixin; Ma, Cui; Zhang, Chen; Ma, Mingfei; Zhang, Fengying; Zhang, Linlin; Chen, Yingli; Cao, Fangyuan; Li, Shuzhen; Zhu, Daling

    2016-07-01

    The high level of reactive oxygen species and up-regulation of mitochondrial fission protein dynamin-related protein-1, both of which involved in pulmonary artery smooth muscle cells (PASMCs) apoptosis, have been detected in the lungs of rodent pulmonary arterial hypertension models. However, the regulatory mechanisms between ROS and DRP1 are poorly understood. In this study, ROS inhibitor, hypoxic rodent PAH models, small interfering RNA, polymerase chain reaction, Western blot, flow cytometry, immunohistochemistry and immunofluorescence were used. We determined that ROS, mainly derive from mitochondria, mediate mitochondria fission of PASMCs contributing to pulmonary vascular remodeling. Meanwhile, we also observed that hypoxia-induced DRP1 expression depends on ROS generation, especially mitochondrial ROS (mROS). Moreover, the levels of ROS and mROS evoked by hypoxia were regulated by DRP1. Furthermore, we verified the apoptosis suppression of PASMCs under hypoxia due to the interaction between ROS/mROS and DRP1. Our study reveals a novel mechanism of hypoxia-induced pulmonary vascular remodeling, suggesting a new therapeutic strategy which is targeting on the positive feedback of ROS/mROS-DRP1 for the treatment of PAH. PMID:27010815

  16. Regulation of cell proliferation and apoptosis in neuroblastoma cells by ccp1, a FGF2 downstream gene

    Directory of Open Access Journals (Sweden)

    Inman Gareth J

    2010-11-01

    Full Text Available Abstract Background Coiled-coil domain containing 115 (Ccdc115 or coiled coil protein-1 (ccp1 was previously identified as a downstream gene of Fibroblast Growth Factor 2 (FGF2 highly expressed in embryonic and adult brain. However, its function has not been characterised to date. Here we hypothesized that ccp1 may be a downstream effecter of FGF2, promoting cell proliferation and protecting from apoptosis. Methods Forced ccp1 expression in mouse embryonic fibroblast (MEF and neuroblastoma SK-N-SH cell line, as well as down-regulation of ccp1 expression by siRNA in NIH3T3, was used to characterize the role of ccp1. Results Ccp1 over-expression increased cell proliferation, whereas down-regulation of ccp1 expression reduced it. Ccp1 was able to increase cell proliferation in the absence of serum. Furthermore, ccp1 reduced apoptosis upon withdrawal of serum in SK-N-SH. The mitogen-activated protein kinase (MAPK or ERK Kinase (MEK inhibitor, U0126, only partially inhibited the ccp1-dependent BrdU incorporation, indicating that other signaling pathway may be involved in ccp1-induced cell proliferation. Induction of Sprouty (SPRY upon FGF2 treatment was accelerated in ccp1 over-expressing cells. Conclusions All together, the results showed that ccp1 regulates cell number by promoting proliferation and suppressing cell death. FGF2 was shown to enhance the effects of ccp1, however, it is likely that other mitogenic factors present in the serum can also enhance the effects. Whether these effects are mediated by FGF2 influencing the ccp1 function or by increasing the ccp1 expression level is still unclear. At least some of the proliferative regulation by ccp1 is mediated by MAPK, however other signaling pathways are likely to be involved.

  17. MAPK Signal Transduction Pathway Regulation: A Novel Mechanism of Rat HSC-T6 Cell Apoptosis Induced by FUZHENGHUAYU Tablet

    Directory of Open Access Journals (Sweden)

    Qi Wang

    2013-01-01

    Full Text Available FUZHENGHUAYU Tablets have been widely used in the treatment of liver fibrosis in China. Here, we investigate the apoptotic effect of FUZHENGHUAYU Tablet in rat liver stellate cell line HSC-T6. HSC-T6 cells were incubated with control serum or drug serum from rats fed with 0.9% NaCl or FUZHENGHUAYU Tablet, respectively. Cells exposed to drug serum showed higher proportions of early and late apoptotic cells than controls. The mRNA levels of collagens I and III, TGF-β1 and α-SMA were reduced by drug serum compared to control serum. Differentially expressed mRNAs and miRNAs were analyzed by microarray and sequencing, respectively. We identified 334 differentially expressed mRNAs and also 60 GOs and two pathways related to the mRNAs. Seventy-five differentially expressed miRNAs were down-regulated by drug serum and 1963 target genes were predicted. 134 GOs up-regulated in drug serum group were linked to miRNA targets, and drug serum also regulated 43 miRNA signal transduction pathways. Protein levels were evaluated by Western blot. Drug serum down-regulated (phospho-SAPK/JNK/(SAPK/JNK and up-regulated phospho-p38/p38 ratios. The study showed that FUZHENGHUAYU Tablet induced apoptosis in rat HSC-T6 cells possibly in part by activating p38 and inhibiting SAPK/JNK.

  18. Hedgehog pathway signaling regulates human colon carcinoma HT-29 epithelial cell line apoptosis and cytokine secretion.

    Directory of Open Access Journals (Sweden)

    Agnes N Yoshimoto

    Full Text Available The Hedgehog (Hh pathway is involved in embryogenesis and physiologic processes including cell survival and proliferation. We used the HT-29 and other human colon carcinoma cell lines to investigate Hh signaling and biological functions in colonic epithelial cells. HT-29 cells were cultured under different conditions and exposed to various stimuli. The expression of Hh pathway components and related genes and proteins were assessed by real-time PCR and immunofluorescence. Viability, apoptosis and cell proliferation were measured by the MTT assay, Annexin-V/7-AAD staining and BrdU uptake, respectively. Chemokines production was measured by ELISA in culture supernatants. Indian and Sonic Hh mRNA levels and the downstream transcription factors Gli-1 and Gli-2 increased following treatment with Hh agonists and butyrate, but decreased upon exposure to cyclopamine or GANT61. BMP4 and BMP7 expression increased after stimulation with Hh agonists. Gli-1 protein expression increased after Hh agonists and decreased following cyclopamine. Exposure to Hh agonists promoted β-catenin reduction and subcellular redistribution. Levels of IL-8 and MCP-1 decreased upon exposure to Hh agonists compared to Hh antagonists, LPS, IFN-γ or EGF. Monocyte chemotaxis decreased upon exposure to supernatants of HT-29 cells treated with Shh compared to Hh antagonists, LPS and IFN-γ. Cellular incorporation of BrdU and cell viability decreased following Hh blockade. Hh agonists abrogated the anti-CD95 induced apoptosis. Hh pathway is a key controller of colon cancer cells, as demonstrated by its effect in dampening inflammatory signals and antagonizing apoptosis. The differential expression of Hh components may underlie abnormalities in the local immune response and in epithelial barrier integrity, with potential homeostatic implications for the development of colonic inflammation and malignancies.

  19. Dietary regulation and localization of apoptosis cascade proteins in the colonic crypt.

    Science.gov (United States)

    Avivi-Green, C; Polak-Charcon, S; Madar, Z; Schwartz, B

    2000-02-01

    This study was designed primarily to assess the localization of apoptosis cascade proteins along the rat colonic crypt and secondarily to test whether the activity and/or localization of these proteins are affected by the enrichment of the diet with the soluble fiber pectin. Expression of apoptosis cascade proteins was assessed in isolated colonocytes harvested from the luminal and basal crypt colonocyte populations. Two different dietary regimens were tested: a standard diet (diet A), and a diet enriched in pectin (diet B), a soluble fiber that undergoes fermentation in the cecum and produces high concentrations of intracolonic short-chain fatty acids. Caspase-1 expression was maximal in luminal colonocytes of rats fed diet B, as evidenced by Western blot and immunohistological analyses. Expression of the cleaved poly(ADP-ribose) polymerase product was elevated in both the luminal and basal colonocytes of the pectin-fed group, whereas in rats fed diet A, the expression was lower, especially in basal crypt colonocytes. The highest expression of the antiapoptotic protein Bcl-2 was observed in the lower compartments of the colonic crypt tissue and was maximal in the rat group fed a standard diet. The apoptotic index in colonocytes of rats fed diet B was higher than that measured in rats fed diet A. Cumulatively, our results indicate that apoptosis cascade proteins are differentially localized along the lumen-crypt axis, and their expression and activity may be controlled by dietary components. These results may, at least partially, account for the documented protective effect of butyrogenic fibers on colorectal cancer. PMID:10679813

  20. Up-Regulation of P21 Inhibits TRAIL-Mediated Extrinsic Apoptosis, Contributing Resistance to SAHA in Acute Myeloid Leukemia Cells

    Directory of Open Access Journals (Sweden)

    Xing Wu

    2014-08-01

    Full Text Available Background/Aim: P21, a multifunctional cell cycle-regulatory molecule, regulates apoptotic cell death. In this study we examined the effect of altered p21 expression on the sensitivity of acute myeloid leukemia cells in response to HDAC inhibitor SAHA treatment and investigated the underlying mechanism. Methods: Stably transfected HL60 cell lines were established in RPMI-1640 with supplementation of G-418. Cell viability was measured by MTT assay. Western blot was applied to assess the protein expression levels of target genes. Cell apoptosis was monitored by AnnexinV-PE/7AAD assay. Results: We showed HL60 cells that that didn't up-regulate p21 expression were more sensitive to SAHA-mediated apoptosis than NB4 and U937 cells that had increased p21 level. Enforced expression of p21 in HL60 cells reduced sensitivity to SAHA and blocked TRAIL-mediated apoptosis. Conversely, p21 silencing in NB4 cells enhanced SAHA-mediated apoptosis and lethality. Finally, we found that combined treatment with SAHA and rapamycin down-regulated p21 and enhanced apoptosis in AML cells. Conclusion: We conclude that up-regulated p21 expression mediates resistance to SAHA via inhibition of TRAIL apoptotic pathway. P21 may serve as a candidate biomarker to predict responsiveness or resistance to SAHA-based therapy in AML patients. In addition, rapamycin may be an effective agent to override p21-mediated resistance to SAHA in AML patients.

  1. Regulation of retinal endothelial cell apoptosis through activation of the IGFBP-3 receptor

    OpenAIRE

    Zhang, Qiuhua; Soderland, Carl; Steinle, Jena J.

    2013-01-01

    The goal of this study was to investigate whether insulin-like growth factor binding protein-3 receptor (IGFBP-3 receptor) is required for IGFBP-3 to inhibit retinal endothelial cell (REC) apoptosis. REC were grown in normal glucose (5 mM) or high glucose medium (25 mM) for 3 days. Once cells reached confluence, they were transfected with an endothelial- specific IGFBP-3 plasmid DNA (non-IGF binding; IGFBP-3 NB) at 1 μg/ml for 24 h. Cell proteins were extracted and analyzed for IGFBP-3 recept...

  2. Down-regulation of ATM Protein Sensitizes Human Prostate Cancer Cells to Radiation-induced Apoptosis*

    OpenAIRE

    Truman, Jean-Philip; Gueven, Nuri; Lavin, Martin; Leibel, Steven; Kolesnick, Richard; Fuks, Zvi; Haimovitz-Friedman, Adriana

    2005-01-01

    Treatment with the protein kinase C activator 12-O tetradecanoylphorbol 12-acetate (TPA) enables radiation-resistant LNCaP human prostate cancer cells to undergo radiation-induced apoptosis, mediated via activation of the enzyme ceramide synthase (CS) and de novo synthesis of the sphingolipid ceramide (Garzotto, M., Haimovitz-Friedman, A., Liao, W. C., White-Jones, M., Huryk, R., Heston, D. W. W., Cardon-Cardo, C., Kolesnick, R., and Fuks, Z. (1999) Cancer Res. 59, 5194-5201). Here, we show t...

  3. Blockade of Apoptosis Signal-Regulating Kinase 1 Attenuates Matrix Metalloproteinase 9 Activity in Brain Endothelial Cells and the Subsequent Apoptosis in Neurons after Ischemic Injury.

    Science.gov (United States)

    Cheon, So Y; Cho, Kyoung J; Kim, So Y; Kam, Eun H; Lee, Jong E; Koo, Bon-Nyeo

    2016-01-01

    Conditions of increased oxidative stress including cerebral ischemia can lead to blood-brain barrier dysfunction via matrix metalloproteinase (MMP). It is known that MMP-9 in particular is released from brain endothelial cells is involved in the neuronal cell death that occurs after cerebral ischemia. In the intracellular signaling network, apoptosis signal-regulating kinase 1 (ASK1) is the main activator of the oxidative stress that is part of the pathogenesis of cerebral ischemia. ASK1 also promotes apoptotic cell death and brain infarction after ischemia and is associated with vascular permeability and the formation of brain edema. However, the relationship between ASK1 and MMP-9 after cerebral ischemia remains unknown. Therefore, the aim of the present study was to determine whether blocking ASK1 would affect MMP-9 activity in the ischemic brain and cultured brain endothelial cells. Our results showed that ASK1 inhibition efficiently reduced MMP-9 activity in vivo and in vitro. In endothelial cell cultures, ASK1 inhibition upregulated phosphatidylinositol 3-kinase/Akt/nuclear factor erythroid 2 [NF-E2]-related factor 2/heme oxygenase-1 signals and downregulated cyclooxygenase-2 signals after hypoxia/reperfusion. Additionally, in neuronal cell cultures, cell death occurred when neurons were incubated with endothelial cell-conditioned medium (EC-CM) obtained from the hypoxia/reperfusion group. However, after incubation with EC-CM and following treatment with the ASK1 inhibitor NQDI-1, neuronal cell death was efficiently decreased. We conclude that suppressing ASK1 decreases MMP-9 activity in brain endothelial cells, and leads to decreased neuronal cell death after ischemic injury. PMID:27642277

  4. Glutathione S-transferase class mu regulation of apoptosis signal-regulating kinase 1 protein during VCD-induced ovotoxicity in neonatal rat ovaries

    Energy Technology Data Exchange (ETDEWEB)

    Bhattacharya, Poulomi; Madden, Jill A. [Department of Animal Science, Iowa State University, Ames, IA 50011 (United States); Sen, Nivedita; Hoyer, Patricia B. [Department of Physiology, University of Arizona, Tucson, AZ 85724 (United States); Keating, Aileen F., E-mail: akeating@iastate.edu [Department of Animal Science, Iowa State University, Ames, IA 50011 (United States)

    2013-02-15

    4-Vinylcyclohexene diepoxide (VCD) destroys ovarian primordial and small primary follicles via apoptosis. In mice, VCD exposure induces ovarian mRNA expression of glutathione S-transferase (GST) family members, including isoform mu (Gstm). Extra-ovarian GSTM negatively regulates pro-apoptotic apoptosis signal-regulating kinase 1 (ASK1) through protein complex formation, which dissociates during stress, thereby initiating ASK1-induced apoptosis. The present study investigated the ovarian response of Gstm mRNA and protein to VCD. Induction of Ask1 mRNA at VCD-induced follicle loss onset was determined. Ovarian GSTM:ASK1 protein complex formation was investigated and VCD exposure effects thereon evaluated. Phosphatidylinositol-3 kinase (PI3K) regulation of GSTM protein was also studied. Postnatal day (PND) 4 rat ovaries were cultured in control media ± 1) VCD (30 μM) for 2–8 days; 2) VCD (30 μM) for 2 days, followed by incubation in control media for 4 days (acute VCD exposure); or 3) LY294002 (20 μM) for 6 days. VCD exposure did not alter Gstm mRNA expression, however, GSTM protein increased (P < 0.05) after 6 days of both the acute and chronic treatments. Ask1 mRNA increased (0.33-fold; P < 0.05) relative to control after 6 days of VCD exposure. Ovarian GSTM:ASK1 protein complex formation was confirmed and, relative to control, the amount of GSTM bound to ASK1 increased 33% (P < 0.05) by chronic but with no effect of acute VCD exposure. PI3K inhibition increased (P < 0.05) GSTM protein by 40% and 71% on d4 and d6, respectively. These findings support involvement of GSTM in the ovarian response to VCD exposure, through regulation of pro-apoptotic ASK1. - Highlights: ► GSTM protein increases in response to ovarian VCD exposure. ► VCD increases Ask1 mRNA at the onset of follicle loss. ► Ovarian GSTM binds more ASK1 protein during VCD-induced ovotoxicity. ► PI3K regulates ovarian GSTM protein.

  5. miR-29b suppresses CML cell proliferation and induces apoptosis via regulation of BCR/ABL1 protein

    Energy Technology Data Exchange (ETDEWEB)

    Li, Yajuan; Wang, Haixia; Tao, Kun [Department of Clinical Hematology, Key Laboratory of Laboratory Medical Diagnostics Designated of Ministry of Education, Chongqing Medical University, 1 Yixueyuan Road, Yuzhong District, Chongqing 400016 (China); Xiao, Qing [Department of Hematology, The First Affiliated Hospital, Chongqing Medical University, 1 Yixueyuan Road, Yuzhong District, Chongqing 400016 (China); Huang, Zhenglan; Zhong, Liang; Cao, Weixi [Department of Clinical Hematology, Key Laboratory of Laboratory Medical Diagnostics Designated of Ministry of Education, Chongqing Medical University, 1 Yixueyuan Road, Yuzhong District, Chongqing 400016 (China); Wen, Jianping [Department of Pathology and Molecular Medicine, McMaster University, Hamilton, Ontario, Canada L8N 3Z5 (Canada); Feng, Wenli, E-mail: fengwlcqmu@sina.com [Department of Clinical Hematology, Key Laboratory of Laboratory Medical Diagnostics Designated of Ministry of Education, Chongqing Medical University, 1 Yixueyuan Road, Yuzhong District, Chongqing 400016 (China)

    2013-05-01

    MicroRNAs (miRNAs) are small RNAs that regulate gene expression posttranscriptionally and are critical for many cellular pathways. Recent evidence has shown that aberrant miRNA expression profiles and unique miRNA signaling pathways are present in many cancers. Here, we demonstrate that miR-29b is markedly lower expressed in CML patient samples. Bioinformatics analysis reveals a conserved target site for miR-29b in the 3′-untranslated region (UTR) of ABL1. miR-29b significantly suppresses the activity of a luciferase reporter containing ABL1-3′UTR and this activity is not observed in cells transfected with mutated ABL1-3′UTR. Enforced expression of miR-29b in K562 cells inhibits cell growth and colony formation ability thereby inducing apoptosis through cleavage of procaspase 3 and PARP. Furthermore, K562 cells transfected with a siRNA targeting ABL1 show similar growth and apoptosis phenotypes as cells overexpression of miR-29b. Collectively, our results suggest that miR-29b may function as a tumor suppressor by targeting ABL1 and BCR/ABL1. - Highlights: ► miR-29b expression was downregulated in CML patients. ► ABL1 was identified as a direct target gene of miR-29b. ► Enforced expression of miR-29b inhibits cell proliferation and induces apoptosis. ► miR-29b might be a therapeutic target to CML.

  6. Nemo like kinase negatively regulates NF-κB activation and coelomocytes apoptosis in Apostichopus japonicus.

    Science.gov (United States)

    Lv, Zhimeng; Li, Chenghua; Zhang, Weiwei; Jin, Chunua; Shao, Yina; Xuemei, Duan; Qingxi, Han

    2016-01-01

    Nuclear factor kappa B (NF-κB) transcription factors are related to several physiological processes, including innate and acquired immunity. In this study, a novel negative regulator of the Nemo-like kinase (NLK) gene was identified from Apostichopus japonicus through PCR (denoted as AjNLK). The complete AjNLK cDNA was of 2335 bp, with a 5'-UTR of 315 bp, a 3'-UTR of 718 bp, and a putative ORF of 1302 bp, and encoded a polypeptide of 433 amino acid residues with a typical serine/threonine protein kinase domain. Blast analysis revealed that AjNLK shared a high degree of structural conservation with its counterparts from other invertebrates and vertebrates. Spatial expression analysis indicated that the expression of AjNLK mRNA transcripts was higher in the tentacles than that in coelomocytes. The expression of AjNLK mRNA in coelomocytes was suppressed after Vibrio splendidus challenge by 0.51-fold and 0.41-fold at 72 and 96 h, respectively, compared with that in the control group. Similarly, AjNLK expression was down-regulated in primary coelomocytes exposed to 1 μg mL(-1) lipopolysaccharide (LPS). Functional investigation further revealed that the NF-κB factor p105 was induced at both mRNA and protein levels after AjNLK silencing in vitro. Meanwhile, the apoptosis of LPS-induced coelomocytes was significantly inhibited in AjNLK siRNA-transfected coelomocytes. These results supported that AjNLK negatively regulated NF-κB activation and cell apoptosis in sea cucumber. PMID:26363086

  7. MicroRNA-124-3p regulates cell proliferation, invasion, apoptosis, and bioenergetics by targeting PIM1 in astrocytoma.

    Science.gov (United States)

    Deng, Danni; Wang, Lei; Chen, Yao; Li, Bowen; Xue, Lian; Shao, Naiyuan; Wang, Qiang; Xia, Xiwei; Yang, Yilin; Zhi, Feng

    2016-07-01

    The PIM1 protein is an important regulator of cell proliferation, the cell cycle, apoptosis, and metabolism in various human cancers. MicroRNAs (miRNAs) are powerful post-transcriptional gene regulators that function through translational repression or transcript destabilization. Therefore, we aimed to identify whether a close relationship exists between PIM1 and miRNAs. PIM1 protein levels and mRNA levels were significantly upregulated in astrocytoma tissues, indicating the oncogenic role of PIM1 in astrocytoma. Further bioinformatics analysis indicated that miR-124-3p targeted the 3'-UTR of PIM1. We also observed an inverse correlation between the miR-124-3p levels and PIM1 protein or mRNA levels in astrocytoma samples. Next, we experimentally confirmed that miR-124-3p directly recognizes the 3'-UTR of the PIM1 transcript and regulates PIM1 expression at both the protein and mRNA levels. Furthermore, we examined the biological consequences of miR-124-3p targeting PIM1 in vitro. We showed that the repression of PIM1 in astrocytoma cancer cells by miR-124-3p suppressed proliferation, invasion, and aerobic glycolysis and promoted apoptosis. We observed that the restoration or inhibition of PIM1 activity resulted in effects that were similar to those induced by miR-124-3p inhibitors or mimics in cancer cells. Finally, overexpression of PIM1 rescued the inhibitory effects of miR-124-3p. In summary, these findings aid in understanding the tumor-suppressive role of miR-124-3p in astrocytoma pathogenesis through the inhibition of PIM1 translation. PMID:27088547

  8. Role of α-crystallin B in regulation of stress induced cardiomyocyte apoptosis.

    Science.gov (United States)

    Ganguly, Subhalakshmi; Mitra, Arkadeep; Sarkar, Sagartirtha

    2014-01-01

    Cardiovascular disease is the leading cause of death worldwide. Recently emerging evidence suggests that cardiomyocyte apoptosis is one of the major pathogenic factors in heart diseases leading to heart failure. Cardiomyocytes undergo apoptosis in response to a wide variety of cellular stresses including protein folding stress at Endoplasmic reticulum (ER). Stressed myocytes elicit an adaptive response referred as Unfolded Protein Response (UPR) by inducing accumulation of heat shock proteins (HSPs) to mitigate the ER stress. HSPs act as molecular chaperons by assisting correct folding of the aggregated misfolded proteins in ER lumen. α-Crystallin B (CRYAB) is an abundant small HSP that confers protection to cardiomyocytes against various stress stimuli. Recent evidence indicates that CRYAB directly interacts with several components of ER stress and also mitochondrial apoptotic pathway. Based on currently available literature this mini review will focus on how CRYAB confers protection to stressed myocardium thereby emphasizing its function as antiapoptotic molecule. Understanding the interplay between CRYAB and the key components in the apoptotic signaling cascade mediated by ER and mitochondria will help in development of novel therapies for cardiac diseases. PMID:25613032

  9. Kaempferol enhances cisplatin's effect on ovarian cancer cells through promoting apoptosis caused by down regulation of cMyc

    Directory of Open Access Journals (Sweden)

    Jiang Bing-Hua

    2010-05-01

    Full Text Available Abstract Background Ovarian cancer is one of the most significant malignancies in the western world. Studies showed that Ovarian cancers tend to grow resistance to cisplatin treatment. Therefore, new approaches are needed in ovarian cancer treatment. Kaempferol is a dietary flavonoid that is widely distributed in fruits and vegetables, and epidemiology studies have revealed a protective effect of kaempferol against ovarian cancer risk. Our early studies also found that kaempferol is effective in reducing vascular endothelial growth factor (VEGF expression in ovarian cancer cells. In this study, we investigated kaempferol's effects on sensitizing ovarian cancer cell growth in response to cisplatin treatment. Results Ten chemicals were screened for sensitizing OVCAR-3 ovarian cancer cell growth in response to cisplatin treatment. For kaempferol, which shows a significant synergistic interaction with cisplatin, expression of ABCC1, ABCC5, ABCC6, NFkB1, cMyc, and CDKN1A genes was further examined. For cisplatin/kaempferol treatments on OVCAR-3 cancer cells, the mRNA levels of ABCC1, ABCC5, and NFkB1 did not change. However, significant inhibition of ABCC6 and cMyc mRNA levels was observed for the cisplatin/kaempferol combined treatment. The CDKN1A mRNA levels were significantly up-regulated by cisplatin/kaempferol treatment. A plot of CDKN1A mRNA levels against that of cMyc gene further revealed a reverse, linear relationship, proving cMyc's regulation on CDKN1A gene expressions. Our work found that kaempferol works synergistically with cisplatin in inhibiting ovarian cancer cell viability, and their inhibition on cell viabilities was induced through inhibiting ABCC6 and cMyc gene transcription. Apoptosis assay showed the addition of 20 μM kaempferol to the cisplatin treatment induces the apoptosis of the cancer cells. Conclusions Kaempferol enhances the effect of cisplatin through down regulation of cMyc in promoting apoptosis of ovarian cancer

  10. A β-integrin from sea cucumber Apostichopus japonicus exhibits LPS binding activity and negatively regulates coelomocyte apoptosis.

    Science.gov (United States)

    Wang, Zhenhui; Shao, Yina; Li, Chenghua; Lv, Zhimeng; Wang, Haihong; Zhang, Weiwei; Zhao, Xuelin

    2016-05-01

    Integrins are a family of membrane glycoproteins, which are the major receptors for extracellular matrix and cell-cell adhesion molecules. In this study, a 1038 bp sequence representing the full-length cDNA of a novel β-integrin subunit (designated as AjITGB) was cloned from Apostichopus japonicusby using combined transcriptome sequencing and RACE approaches. The deduced amino acid sequence of AjITGB shared a conserved tripeptide Arg-Gly-Asp (RGD) binding domain with an S-diglyceridecysteine or N-Palm cysteine residue (C(31)), a transmembrane domain, and a β-integrin cytoplasmic domain. Spatial distribution analysis showed that AjITGB was constitutively expressed in all tested tissues with dominant expression in the muscles and weak expression in the respiratory tree. The pathogen Vibrio splendidus challenge and LPS stimulation could both significantly down-regulate the mRNA expression of AjITGB. Functional investigation revealed that recombinant AjITGB displayed higher LPS binding activity but lower binding activity to PGN and MAN. More importantly, knockdown of AjITGB by specific siRNA resulted in the significant promotion of coelomocyte apoptosis in vitro. Results indicated that AjITGB may serve as an apoptosis inhibitor with LPS binding activity during host-pathogen interaction in sea cucumber. PMID:26994670

  11. Cerebral Microvascular Endothelial Cell Apoptosis after Ischemia: Role of Enolase-Phosphatase 1 Activation and Aci-Reductone Dioxygenase 1 Translocation.

    Science.gov (United States)

    Zhang, Yuan; Wang, Ting; Yang, Ke; Xu, Ji; Ren, Lijie; Li, Weiping; Liu, Wenlan

    2016-01-01

    Enolase-phosphatase 1 (ENOPH1), a newly discovered enzyme of the methionine salvage pathway, is emerging as an important molecule regulating stress responses. In this study, we investigated the role of ENOPH1 in blood brain barrier (BBB) injury under ischemic conditions. Focal cerebral ischemia induced ENOPH1 mRNA and protein expression in ischemic hemispheric microvessels in rats. Exposure of cultured brain microvascular endothelial cells (bEND3 cells) to oxygen-glucose deprivation (OGD) also induced ENOPH1 upregulation, which was accompanied by increased cell death and apoptosis reflected by increased 3-(4, 5-Dimethylthiazol-2-yl)-2, 5- diphenyltetrazolium bromide formation, lactate dehydrogenase release and TUNEL staining. Knockdown of ENOPH1 expression with siRNA or overexpressing ENOPH1 with CRISPR-activated plasmids attenuated or potentiated OGD-induced endothelial cell death, respectively. Moreover, ENOPH1 knockdown or overexpression resulted in a significant reduction or augmentation of reactive oxygen species (ROS) generation, apoptosis-associated proteins (caspase-3, PARP, Bcl-2 and Bax) and Endoplasmic reticulum (ER) stress proteins (Ire-1, Calnexin, GRP78 and PERK) in OGD-treated endothelial cells. OGD upregulated the expression of ENOPH1's downstream protein aci-reductone dioxygenase 1 (ADI1) and enhanced its interaction with ENOPH1. Interestingly, knockdown of ENOPH1 had no effect on OGD-induced ADI1 upregulation, while it potentiated OGD-induced ADI1 translocation from the nucleus to the cytoplasm. Lastly, knockdown of ENOPH1 significantly reduced OGD-induced endothelial monolayer permeability increase. In conclusion, our data demonstrate that ENOPH1 activation may contribute to OGD-induced endothelial cell death and BBB disruption through promoting ROS generation and the activation of apoptosis associated proteins, thus representing a new therapeutic target for ischemic stroke. PMID:27630541

  12. Autophagy regulates the apoptosis of bone marrow-derived mesenchymal stem cells under hypoxic condition via AMP-activated protein kinase/mammalian target of rapamycin pathway.

    Science.gov (United States)

    Zhang, Zheng; Yang, Ming; Wang, Yabin; Wang, Le; Jin, Zhitao; Ding, Liping; Zhang, Lijuan; Zhang, Lina; Jiang, Wei; Gao, Guojie; Yang, Junke; Lu, Bingwei; Cao, Feng; Hu, Taohong

    2016-06-01

    Bone marrow-derived mesenchymal stem cells (BM-MSCs) have been demonstrated as an ideal autologous stem cells source for cell-based therapy for myocardial infarction (MI). However, poor viability of donor stem cells after transplantation limits their therapeutic efficiency, whereas the underlying mechanism is still poorly understood. Autophagy, a highly conserved process of cellular degradation, is required for maintaining homeostasis and normal function. Here, we investigated the potential role of autophagy on apoptosis in BM-MSCs induced by hypoxic injury. BM-MSCs, isolated from male C57BL/6 mice, were subjected to hypoxia and serum deprivation (H/SD) injury for 6, 12, and 24 h, respectively. The autophagy state was regulated by 3-methyladenine (3MA) and rapamycin administration. Furthermore, compound C was administrated to inhibit AMPK. The apoptosis induced by H/SD was determined by TUNEL assays. Meanwhile, autophagy was measured by GFP-LC3 plasmids transfection and transmission electron microscope. Moreover, protein expressions were evaluated by Western blot assay. In the present study, we found that hypoxic stress increased autophagy and apoptosis in BM-MSCs time dependently. Meanwhile, hypoxia increased the activity of AMPK/mTOR signal pathway. Moreover, increased apoptosis in BM-MSCs under hypoxia was abolished by 3-MA, whereas was aggravated by rapamycin. Furthermore, the increased autophagy and apoptosis in BM-MSCs induced by hypoxia were abolished by AMPK inhibitor compound C. These data provide evidence that hypoxia induced AMPK/mTOR signal pathway activation which regulated the apoptosis and autophagy in BM-MSCs. Furthermore, the apoptosis of BM-MSCs under hypoxic condition was regulated by autophagy via AMPK/mTOR pathway. PMID:27005844

  13. Neuropeptide Y protects kidney against cisplatin-induced nephrotoxicity by regulating p53-dependent apoptosis pathway

    Science.gov (United States)

    Kim, Namoh; Min, Woo-Kie; Park, Min Hee; Lee, Jong Kil; Jin, Hee Kyung; Bae, Jae-sung

    2016-01-01

    Cisplatin is a platinum-based chemotherapeutic drug for treating various types of cancers. However, the use of cisplatin is limited by its negative effect on normal tissues, particularly nephrotoxicity. Various mechanisms such as DNA adduct formation, mitochondrial dysfunction, oxidative stress, and apoptosis are involved in the adverse effect induced by cisplatin treatment. Several studies have suggested that neuropeptide Y (NPY) is involved in neuroprotection as well as restoration of bone marrow dysfunction from chemotherapy induced nerve injury. However, the role of NPY in chemotherapy-induced nephrotoxicity has not been studied. Here, we show that NPY rescues renal dysfunction by reducing the expression of pro-apoptotic proteins in cisplatin induced nephrotoxicity through Y1 receptor, suggesting that NPY can protect kidney against cisplatin nephrotoxicity as a possible useful agent to prevent and treat cisplatin-induced nephrotoxicity. [BMB Reports 2016; 49(5): 288-292] PMID:26728272

  14. miR-96 regulates FOXO1-mediated cell apoptosis in bladder cancer.

    Science.gov (United States)

    Guo, Yan; Liu, Huihui; Zhang, Hui; Shang, Chao; Song, Yongsheng

    2012-09-01

    Transitional cell carcinoma (TCC) is one of the most common types of malignancies and a leading cause of genitourinary system cancer mortality worldwide. The tumor suppressor gene FOXO1, a member of the forkhead box O (FOXO) subfamily of transcription factors, is downregulated in a number of cancers, including TCC; however, the underlying mechanisms are poorly understood. In the present study, we used microRNA (miRNA) target prediction algorithms to identify a conserved potential miR-96 binding site in the 3'-untranslated region (3'-UTR) of FOXO1. Using quantitative real-time PCR (qRT-PCR) and northern blot analysis, we identified that miR-96 was downregulated in TCC tissues compared to normal bladder tissues (NB), suggesting that the loss of FOXO1 expression in TCC may be mediated by miR-96. To confirm this, we transfected pre-miR-96/anti-miR-96 into the T24 TCC cell line and revealed that miR-96 expression was sufficient to significantly reduce FOXO1 expression. Conversely, FOXO1 expression was not completely restored by the inhibition of miR-96 in T24 cells. Moreover, RNA silencing of FOXO1 significantly reduced miR-96 inhibitor-mediated T24 cell apoptosis. In conclusion, our study demonstrates that the miR-96 targeting of FOXO1 is upregulated in TCC; in addition, TCC tumorigenesis may be partly due to the ability of miR-96 to promote FOXO1 repression, thereby bypassing cell apoptosis controls. PMID:23741253

  15. E2Fs regulate the expression of genes involved in differentiation, development, proliferation, and apoptosis

    DEFF Research Database (Denmark)

    Müller, H; Bracken, A P; Vernell, R;

    2001-01-01

    The retinoblastoma protein (pRB) and its two relatives, p107 and p130, regulate development and cell proliferation in part by inhibiting the activity of E2F-regulated promoters. We have used high-density oligonucleotide arrays to identify genes in which expression changed in response to activation...

  16. Down-regulation of PPARgamma1 suppresses cell growth and induces apoptosis in MCF-7 breast cancer cells

    Directory of Open Access Journals (Sweden)

    Wallis Natalie K

    2008-12-01

    Full Text Available Abstract Background Peroxisome proliferator-activated receptor gamma (PPARγ is a member of the nuclear hormone receptor superfamily and is highly expressed in many human tumors including breast cancer. PPARγ has been identified as a potential target for breast cancer therapy based on the fact that its activation by synthetic ligands affects the differentiation, proliferation, and apoptosis of cancer cells. However, the controversial nature of current studies and disappointing results from clinical trials raise questions about the contribution of PPARγ signaling in breast cancer development in the absence of stimulation by exogenous ligands. Recent reports from both in vitro and in vivo studies are inconsistent and suggest that endogenous activation of PPARγ plays a much more complex role in initiation and progression of cancer than previously thought. Results We have previously demonstrated that an increase in expression of PPARγ1 in MCF-7 breast cancer cells is driven by a tumor-specific promoter. Myc-associated zinc finger protein (MAZ was identified as a transcriptional mediator of PPARγ1 expression in these cells. In this study, using RNA interference (RNAi to inhibit PPARγ1 expression directly or via down-regulation of MAZ, we report for the first time that a decrease in PPARγ1 expression results in reduced cellular proliferation in MCF-7 breast cancer cells. Furthermore, we demonstrate that these changes in proliferation are associated with a significant decrease in cell transition from G1 to the S phase. Using a dominant-negative mutant of PPARγ1, Δ462, we confirmed that PPARγ1 acts as a pro-survival factor and showed that this phenomenon is not limited to MCF-7 cells. Finally, we demonstrate that down-regulation of PPARγ1 expression leads to an induction of apoptosis in MCF-7 cells, confirmed by analyzing Bcl-2 expression and PARP-1 cleavage. Conclusion Thus, these findings suggest that an increase in PPARγ1 signaling

  17. Cell Cycle and Apoptosis Regulatory Protein (CARP)-1 is Expressed inOsteoblasts and Regulated by PTH

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, Sonali; Mahalingam, Chandrika D.; Das, Varsha [Department of Internal Medicine/Endocrinology, Wayne State University School of Medicine, Detroit, MI 48201 (United States); Jamal, Shazia [Department of Oncology, Wayne State University School of Medicine, Detroit, MI 48201 (United States); Levi, Edi [Department of Oncology, Wayne State University School of Medicine, Detroit, MI 48201 (United States); Department of Pathology, Wayne State University School of Medicine, Detroit, MI 48201 (United States); Rishi, Arun K. [Department of Oncology, Wayne State University School of Medicine, Detroit, MI 48201 (United States); Barbara Ann Karmanos Cancer Institute, Wayne State University School of Medicine, Detroit, MI 48201 (United States); VA Medical Center, Wayne State University School of Medicine, Detroit, MI 48201 (United States); Datta, Nabanita S., E-mail: ndatta@med.wayne.edu [Department of Internal Medicine/Endocrinology, Wayne State University School of Medicine, Detroit, MI 48201 (United States); Barbara Ann Karmanos Cancer Institute, Wayne State University School of Medicine, Detroit, MI 48201 (United States); Cardiovascular Research Institute, Wayne State University School of Medicine, Detroit, MI 48201 (United States)

    2013-07-12

    Highlights: •CARP-1 is identified for the first time in bone cells. •PTH downregulates CARP-1 expression in differentiated osteoblasts. •PTH displaces CARP-1 from nucleus to the cytoplasm in differentiated osteoblasts. •Downregulation of CARP-1 by PTH involves PKA, PKC and P-p38 MAPK pathways. -- Abstract: Bone mass is dependent on osteoblast proliferation, differentiation and life-span of osteoblasts. Parathyroid hormone (PTH) controls osteoblast cell cycle regulatory proteins and suppresses mature osteoblasts apoptosis. Intermittent administration of PTH increases bone mass but the mechanism of action are complex and incompletely understood. Cell Cycle and Apoptosis Regulatory Protein (CARP)-1 (aka CCAR1) is a novel transducer of signaling by diverse agents including cell growth and differentiation factors. To gain further insight into the molecular mechanism, we investigated involvement of CARP-1 in PTH signaling in osteoblasts. Immunostaining studies revealed presence of CARP-1 in osteoblasts and osteocytes, while a minimal to absent levels were noted in the chondrocytes of femora from 10 to 12-week old mice. Treatment of 7-day differentiated MC3T3-E1 clone-4 (MC-4) mouse osteoblastic cells and primary calvarial osteoblasts with PTH for 30 min to 5 h followed by Western blot analysis showed 2- to 3-fold down-regulation of CARP-1 protein expression in a dose- and time-dependent manner compared to the respective vehicle treated control cells. H-89, a Protein Kinase A (PKA) inhibitor, suppressed PTH action on CARP-1 protein expression indicating PKA-dependent mechanism. PMA, a Protein Kinase C (PKC) agonist, mimicked PTH action, and the PKC inhibitor, GF109203X, partially blocked PTH-dependent downregulation of CARP-1, implying involvement of PKC. U0126, a Mitogen-Activated Protein Kinase (MAPK) Kinase (MEK) inhibitor, failed to interfere with CARP-1 suppression by PTH. In contrast, SB203580, p38 inhibitor, attenuated PTH down-regulation of CARP-1

  18. Resolvin D1 Protects Lipopolysaccharide-induced Acute Kidney Injury by Down-regulating Nuclear Factor-kappa B Signal and Inhibiting Apoptosis

    Directory of Open Access Journals (Sweden)

    Yu-Liang Zhao

    2016-01-01

    Conclusion: In LPS-induced AKI, RvD1 could decrease TNF-α level, ameliorate kidney pathological injury, protect kidney function, and improve animal survival by down-regulating NF-κB inflammatory signal as well as inhibiting renal cell apoptosis.

  19. MicroRNA-302/367 Cluster Governs hESC Self-Renewal by Dually Regulating Cell Cycle and Apoptosis Pathways

    Directory of Open Access Journals (Sweden)

    Zhonghui Zhang

    2015-04-01

    Full Text Available miR-302/367 is the most abundant miRNA cluster in human embryonic stem cells (hESCs and can promote somatic cell reprogramming. However, its role in hESCs remains poorly understood. Here, we studied functional roles of the endogenous miR-302/367 cluster in hESCs by employing specific TALE-based transcriptional repressors. We revealed that miR-302/367 cluster dually regulates hESC cell cycle and apoptosis in dose-dependent manner. Gene profiling and functional studies identified key targets of the miR-302/367 cluster in regulating hESC self-renewal and apoptosis. We demonstrate that in addition to its role in cell cycle regulation, miR-302/367 cluster conquers apoptosis by downregulating BNIP3L/Nix (a BH3-only proapoptotic factor and upregulating BCL-xL expression. Furthermore, we show that butyrate, a natural compound, upregulates miR-302/367 cluster expression and alleviates hESCs from apoptosis induced by knockdown of miR-302/367 cluster. In summary, our findings provide new insights in molecular mechanisms of how miR-302/367 cluster regulates hESCs.

  20. Crosstalk between Smad and Mitogen-Activated Protein Kinases for the Regulation of Apoptosis in Cyclosporine A- Induced Renal Tubular Injury

    Directory of Open Access Journals (Sweden)

    Hideyuki Iwayama

    2011-10-01

    Full Text Available Background/Aims: It remains elusive whether there is a crosstalk between Smad and mitogen-activated protein kinases (MAPKs and whether it regulates cyclosporine A (CyA-induced apoptosis in renal proximal tubular cells (RPTCs. Methods: The effect of CyA on nuclear translocation of Smad2/3 and MAPKs (measured by Western blotting or immunofluorescence and apoptosis (determined by Hoechst 33258 staining was examined in HK-2 cells. Results: CyA induced apoptosis at 24 h and nuclear translocation of phosphorylated (p-Smad2/3 at 3 h, which was continued till 24 h. CyA enhanced the expression of p-ERK at 1 h, which was continued till 24 h, and of p-p38MAPK at 1–6 h, which returned to control level at 12 h. CyA did not affect JNK. An inhibitor of ERK, PD98059, prevented CyA-induced nuclear translocation of Smad2/3 and apoptosis. An inhibitor of p38MAPK, SB202190, deteriorated CyA-induced nuclear translocation of p-Smad2/3. Epidermal growth factor (EGF activated ERK and p38MAPK but not JNK. EGF-induced activation of MAPKs ameliorated CyA-induced nuclear translocation of p-Smad2/3 and apoptosis. Inhibition of p38MAPK but not of ERK abolished the protective effect of EGF on CyA-induced nuclear translocation of p-Smad2/3 and apoptosis. Conclusion: Crosstalk between R-Smad and p38MAPK/ERK, but not JNK differentially regulates apoptosis in CyA-induced RPTC injury.

  1. Safrole oxide induces apoptosis by up-regulating Fas and FasL instead of integrin beta4 in A549 human lung cancer cells.

    Science.gov (United States)

    Du, AiYing; Zhao, BaoXiang; Miao, JunYing; Yin, DeLing; Zhang, ShangLi

    2006-04-01

    Previously, we found that 3,4-(methylenedioxy)-1-(2',3'-epoxypropyl)-benzene (safrole oxide) induced a typical apoptosis in A549 human lung cancer cells by activating caspase-3, -8, and -9. In this study, we further investigated which upstream pathways were activated by safrole oxide during the apoptosis. Immunofluorescence assay combined with laser scanning confocal microscopy revealed that both Fas and Fas ligand (FasL) were up-regulated by the small molecule. In addition, Fas protein distribution was altered, showing a clustering distribution instead of a homogeneous one. Subsequently, Western blot analysis confirmed the up-regulations of Fas and its membrane-binding form of FasL (m-FasL), as well as P53 protein. Conversely, safrole oxide hardly affected integrin beta4 subunit expression or distribution, which was reflected from the data obtained by immunofluorescence assay combined with laser scanning confocal microscopy. The results suggested that Fas/FasL pathway might be involved in safrole oxide-induced apoptosis of A549 cells, while integrin beta4 might be irrelevant to the apoptosis. Nevertheless, we first found the strong expression of integrin beta4 in A549 cells. The study first suggested that safrole oxide might be used as a small molecular promoter of Fas/FasL pathway to elicit apoptosis in A549 cells, which would lay the foundation for us to insight into the new strategies for lung cancer therapy.

  2. Structural and Biochemical Studies of TIGAR (TP53-induced Glycolysis and Apoptosis Regulator)

    Energy Technology Data Exchange (ETDEWEB)

    Li, H.; Jogl, G

    2009-01-01

    Activation of the p53 tumor suppressor by cellular stress leads to variable responses ranging from growth inhibition to apoptosis. TIGAR is a novel p53-inducible gene that inhibits glycolysis by reducing cellular levels of fructose-2,6-bisphosphate, an activator of glycolysis and inhibitor of gluconeogenesis. Here we describe structural and biochemical studies of TIGAR from Danio rerio. The overall structure forms a histidine phosphatase fold with a phosphate molecule coordinated to the catalytic histidine residue and a second phosphate molecule in a position not observed in other phosphatases. The recombinant human and zebra fish enzymes hydrolyze fructose-2,6-bisphosphate as well as fructose-1,6-bisphosphate but not fructose 6-phosphate in vitro. The TIGAR active site is open and positively charged, consistent with its enzymatic function as bisphosphatase. The closest related structures are the bacterial broad specificity phosphatase PhoE and the fructose-2,6-bisphosphatase domain of the bifunctional 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase. The structural comparison shows that TIGAR combines an accessible active site as observed in PhoE with a charged substrate-binding pocket as seen in the fructose-2,6-bisphosphatase domain of the bifunctional enzyme.

  3. Nucleolin down-regulation is involved in ADP-induced cell cycle arrest in S phase and cell apoptosis in vascular endothelial cells.

    Directory of Open Access Journals (Sweden)

    Wenmeng Wang

    Full Text Available High concentration of extracellular ADP has been reported to induce cell apoptosis, but the molecular mechanisms remain not fully elucidated. In this study, we found by serendipity that ADP treatment of human umbilical vein endothelial cells (HUVEC and human aortic endothelial cells (HAEC down-regulated the protein level of nucleolin in a dose- and time-dependent manner. ADP treatment did not decrease the transcript level of nucloelin, suggesting that ADP might induce nucleolin protein degradation. HUVEC and HAEC expressed ADP receptor P2Y13 receptor, but did not express P2Y1 or P2Y12 receptors. However, P2Y1, 12, 13 receptor antagonists MRS2179, PSB0739, MRS2211 did not inhibit ADP-induced down-regulation of nucleolin. Moreover, MRS2211 itself down-regulated nucleolin protein level. In addition, 2-MeSADP, an agonist for P2Y1, 12 and 13 receptors, did not down-regulate nucleolin protein. These results suggested that ADP-induced nucleolin down-regulation was not due to the activation of P2Y1, 12, or 13 receptors. We also found that ADP treatment induced cell cycle arrest in S phase, cell apoptosis and cell proliferation inhibition via nucleolin down-regulation. The over-expression of nucleolin by gene transfer partly reversed ADP-induced cell cycle arrest, cell apoptosis and cell proliferation inhibition. Furthermore, ADP sensitized HUVEC to cisplatin-induced cell death by the down-regulation of Bcl-2 expression. Taken together, we found, for the first time to our knowledge, a novel mechanism by which ADP regulates cell proliferation by induction of cell cycle arrest and cell apoptosis via targeting nucelolin.

  4. Down-Regulation of Notch-1 Is Associated With Akt and FoxM1 in Inducing Cell Growth Inhibition and Apoptosis in Prostate Cancer Cells

    OpenAIRE

    Wang, Zhiwei; Li, Yiwei; Ahmad, Aamir; Banerjee, Sanjeev; Azmi, Asfar S; Kong, Dejuan; Wojewoda, Christine; Miele, Lucio; Sarkar, Fazlul H

    2011-01-01

    Although many studies have been done to uncover the mechanisms by which down-regulation of Notch-1 exerts its anti-tumor activity against a variety of human malignancies, the precise molecular mechanisms remain unclear. In the present study, we investigated the cellular consequence of Notch-1 down-regulation and also assessed the molecular consequence of Notch-1-mediated alterations of its downstream targets on cell viability and apoptosis in prostate cancer (PCa) cells. We found that the dow...

  5. Regulation of Apoptosis in African Swine Fever Virus–Infected Macrophages

    Directory of Open Access Journals (Sweden)

    Laslo Zsak

    2002-01-01

    Full Text Available A number of viruses have evolved antiapoptotic mechanisms to promote infected-cell survival, either to ensure efficient productive viral replication or to promote long-term survival of virus-infected cells. Recent studies identified critical African swine fever virus genes involved in the complex regulation of ASFV-host interactions. Here we review the present knowledge of the recently identified ASFV genes with special attention to those which affect viral virulence, host range, and pathogenesis by regulating viral-induced apoptotic mechanisms.

  6. Synergistic Effect of Subtoxic-dose Cisplatin and TRAIL to Mediate Apoptosis by Down-regulating Decoy Receptor 2 and Up-regulating Caspase-8, Caspase-9 and Bax Expression on NCI-H460 and A549 Cells

    Directory of Open Access Journals (Sweden)

    Xiaoyan Zhang

    2013-05-01

    Full Text Available Objective(s: Although tumor necrosis factor-related apoptosis-inducing ligand (TRAIL can selectively induce apoptosis in tumor cells, more than half of tumors including non-small cell lung cancer (NSCLC exhibit TRAIL-resistance. The purpose of this study was to determine whether subtoxic-dose cisplatin and TRAIL could synergistically enhance apoptosis on NSCLC cells and investigate its underlying mechanisms. Materials and Methods:NCI-H460 and A549 cells were treated with TRAIL alone, cisplatin alone or combination treatment in this study. The cytotoxicity was evaluated according to Sulforhodamine B assay, and apoptosis was examined using Hoechst 33342 staining and flow cytometry. The mRNA and protein levels of TRAIL receptors and apoptotic proteins including caspase-8, caspase-9, Bcl-2 and Bax were determined by RT-PCR and Western blotting, respectively. Results:Our results showed that NCI-H460 cells were sensitive to TRAIL, whereas A549 cells were resistant. However, subtoxic-dose cisplatin could enhance the both cells to TRAIL-mediated cell proliferation inhibition and apoptosis. The underlying mechanisms might be associated with the down-regulation of DcR2 and up-regulation of Caspase-8, Caspase-9 and Bax. Conclusion:Subtoxic-dose cisplatin could enhance both TRAIL- sensitive and TRAIL- resistant NSCLC cells to TRAIL-mediated apoptosis. These findings motivated further studies to evaluate such a combinatory therapeutic strategy against NSCLC in the animal models.

  7. CXCL12 chemokine expression and secretion regulates colorectal carcinoma cell anoikis through Bim-mediated intrinsic apoptosis.

    Directory of Open Access Journals (Sweden)

    Luke J Drury

    Full Text Available BACKGROUND: Resistance to anoikis, apoptosis triggered by a loss of cellular adhesion to the underlying extracellular matrix, is a hallmark of metastatic cancer. Previously we have shown re-establishment of CXCL12 expression in colorectal carcinoma cells inhibits metastasis by enhancing anoikis sensitivity. The objective of these studies was to define the signaling mechanisms regulating CXCL12-mediated anoikis. METHODOLOGY/PRINCIPAL FINDINGS: Adhesion, examined by crystal violet staining, immunofluorescence microscopy, and immunoblot analysis indicated decreased focal adhesion signaling corresponding with loss of adhesion in cells constitutively simulated by CXCL12. Loss of adhesion was inhibited by pertussis toxin treatment, indicating CXCL12 regulating anoikis through G(αi-protein coupled receptors. Non-adherent HCT116 and HT29 colorectal carcinoma cells expressing CXCL12 exhibited enhanced anoikis sensitivity by propidium iodide staining, caspase activity assays, and immunoblot compared to GFP control cells. CXCL12 producing carcinomas cultured on poly-HEMA displayed heightened Bim and loss of Mcl-1 and Bcl-2 preceding cytochrome c release, and caspase-9 activation. RNAi knockdown of Bim reversed anoikis sensitivity of CXCL12-expressing cells and fostered increased soft-agar foci formation and hepatic tumors in an orthotopic mouse model of metastasis. CONCLUSIONS/SIGNIFICANCE: These data indicate CXCL12 provides a barrier to metastasis by increasing anoikis via activation of a Bim-mediated intrinsic apoptotic pathway. These results underscore the importance of retaining CXCL12 expression to sensitize colorectal carcinomas to anoikis and minimize tumor progression.

  8. Atorvastatin Inhibits Myocardial Apoptosis in a Swine Model of Coronary Microembolization by Regulating PTEN/PI3K/Akt Signaling Pathway

    Directory of Open Access Journals (Sweden)

    Jiangyou Wang

    2016-01-01

    Full Text Available Background/Aims: Phosphatase and tensin homolog deleted on chromosome ten (PTEN has been recognized as a promoter of apoptosis in various tissues, and revealed to be up-regulated in circumstances of coronary microembolization (CME. However, whether this functional protein could be modified by pretreatment of atorvastatin in models of CME has not been disclosed yet. Methods: Swine CME was induced by intra-coronary injection of inertia plastic microspheres (diameter 42 μm into left anterior descending coronary, with or without pretreatment of atorvastatin or PTEN siRNA. Echocardiologic measurements, pathologic examination, TUNEL staining and western blotting were applied to assess their functional, morphological and molecular effects in CME. Results: PTEN were aberrantly up-regulated in cardiomyocytes following CME, with both the mRNA and protein levels increased after CME modeling. Pretreatment with atorvastatin could attenuate the induction of PTEN. Furthermore, down-regulation of PTEN in vivo via siRNA was associated with an improved cardiac function, attenuated myocardial apoptosis, and concomitantly inhibited expressions of key proapoptotic proteins such as Bax, cleaved-caspase-3. Interestingly, atorvastatin could markedly attenuate PTEN expression and therefore partially reverse cardiac dysfunction and attenuate the apoptosis of the myocardium following CME. Conclusion: Modulation of PTEN was probably as a potential mechanism involved in the beneficial effects of pretreatment of atorvastatin to cardiac function and apoptosis in large animal models of CME.

  9. Opposed arsenite-mediated regulation of p53-survivin is involved in neoplastic transformation, DNA damage, or apoptosis in human keratinocytes

    International Nuclear Information System (INIS)

    Highlights: ► Different concentrations of arsenite cause biphasic effects in HaCaT cells. ► p53-survivin signal pathway plays a role in arsenite-induced biphasic effects. ► ERKs inactivate p53, but improve survivin expression by NF-κB/mot-2. ► JNKs block survivin expression by preventing p53 from mdm2-mediated degradation. ► ERKs and JNKs play roles in arsenite-induced biphasic effects. -- Abstract: Biphasic dose–response relationship induced by environmental agents is often characterized with the effect of low-dose stimulation and high dose inhibition. Some studies showed that arsenite may induce cell proliferation and apoptosis via biphasic dose–response relationship in human cells; however, mechanisms underlying this phenomenon are not well understood. Our present study shows that, for human keratinocytes (HaCaT) cells, a low concentration of arsenite activates extracellular signal-regulated kinases (ERKs), which leads to up-regulation of nuclear factor κB (NF-κB) binding to DNA and to elevated, NF-κB-dependent expression of mot-2 (a p53 inhibitor) and survivin (an inhibitor of apoptosis). Activation of p53 is blocked, and neoplastic transformation is enhanced. Inhibition of ERKs reduces cell proliferation and neoplastic transformation. In contrast, a high concentration of arsenite activates c-Jun N-terminal kinases (JNKs), positive regulators of p53, by binding to p53 and preventing its murine double minute 2 (mdm2)-mediated degradation. The elevated levels of p53 lead to repair of DNA damage and apoptosis. Inhibition of JNKs increases DNA damage but decreases apoptosis. By identifying a mechanism whereby ERKs and JNKs-mediated regulation of the p53-survivin signal pathway is involved in the biphasic effects of arsenite on human keratinocytes, our data expand understanding of arsenite-induced cell proliferation, neoplastic transformation, DNA damage, and apoptosis.

  10. Nuclear translocation of annexin 1 following oxygen-glucose deprivation-reperfusion induces apoptosis by regulating Bid expression via p53 binding.

    Science.gov (United States)

    Li, Xing; Zhao, Yin; Xia, Qian; Zheng, Lu; Liu, Lu; Zhao, Baoming; Shi, Jing

    2016-01-01

    Previous data have suggested that the nuclear translocation of annexin 1 (ANXA1) is involved in neuronal apoptosis after ischemic stroke. As the mechanism and function of ANXA1 nuclear migration remain unclear, it is important to clarify how ANXA1 performs its role as an apoptosis 'regulator' in the nucleus. Here we report that importazole (IPZ), an importin β (Impβ)-specific inhibitor, decreased ANXA1 nuclear accumulation and reduced the rate of neuronal death induced by nuclear ANXA1 migration after oxygen-glucose deprivation-reoxygenation (OGD/R). Notably, ANXA1 interacted with the Bid (BH3-interacting-domain death agonist) promoter directly; however; this interaction could be partially blocked by the p53 inhibitor pifithrin-α (PFT-α). Accordingly, ANXA1 was shown to interact with p53 in the nucleus and this interaction was enhanced following OGD/R. A luciferase reporter assay revealed that ANXA1 was involved in the regulation of p53-mediated transcriptional activation after OGD/R. Consistent with this finding, the nuclear translocation of ANXA1 after OGD/R upregulated the expression of Bid, which was impeded by IPZ, ANXA1 shRNA, or PFT-α. Finally, cell-survival testing demonstrated that silencing ANXA1 could improve the rate of cell survival and decrease the expression of both cleaved caspase-3 and cleaved poly(ADP-ribose) polymerase. These data suggested that Impβ-dependent nuclear ANXA1 migration participates in the OGD/R-dependent induction of neuronal apoptosis. ANXA1 interacts with p53 and promotes p53 transcriptional activity, which in turn regulates Bid expression. Silencing ANXA1 decreases the expression of Bid and suppresses caspase-3 pathway activation, thus improving cell survival after OGD/R. This study provides a novel mechanism whereby ANXA1 regulates apoptosis, suggesting the potential for a previously unidentified treatment strategy in minimizing apoptosis after OGD/R. PMID:27584794

  11. miR-122 regulates p53/Akt signalling and the chemotherapy-induced apoptosis in cutaneous T-cell lymphoma

    DEFF Research Database (Denmark)

    Manfè, Valentina; Biskup, Edyta; Rosbjerg, Anne;

    2012-01-01

    . Using a recently established model in which apoptosis of CTCL cell lines is induced by Notch-1 inhibition by γ-secretase inhibitors (GSIs), we found that miR-122 was significantly increased in the apoptotic cells. miR-122 up-regulation was not specific for GSI-1 but was also seen during apoptosis...... induced by chemotherapies including doxorubicin and proteasome blockers (bortezomib, MG132). miR-122 was not expressed in quiescent T-cells, but was detectable in CTCL: in lesional skin in mycosis fungoides and in Sézary cells purified from peripheral blood. In situ hybridization results showed that miR......-122 was expressed in the malignant T-cell infiltrate and increased in the advanced stage mycosis fungoides. Surprisingly, miR-122 overexpression decreased the sensitivity to the chemotherapy-induced apoptosis via a signaling circuit involving the activation of Akt and inhibition of p53. We have also...

  12. Bex2 regulates cell proliferation and apoptosis in malignant glioma cells via the c-Jun NH2-terminal kinase pathway

    International Nuclear Information System (INIS)

    Highlights: ► The expression levels of Bex2 markedly increased in glioma tissues. ► Bex2 over-expression promoted cell proliferation, while its down-regulation inhibited cell growth. ► Bex2 down-regulation promoted cell apoptosis via JNK/c-Jun signaling pathway. -- Abstract: The function of Bex2, a member of the Brain Expressed X-linked gene family, in glioma is controversial and its mechanism is largely unknown. We report here that Bex2 regulates cell proliferation and apoptosis in malignant glioma cells via the c-Jun NH2-terminal kinase (JNK) pathway. The expression level of Bex2 is markedly increased in glioma tissues. We observed that Bex2 over-expression promotes cell proliferation, while down-regulation of Bex2 inhibits cell growth. Furthermore, Bex2 down-regulation promotes cell apoptosis and activates the JNK pathway; these effects were abolished by administration of the JNK specific inhibitor, (SP600125). Thus, Bex2 may be an important player during the development of glioma.

  13. c-Abl is an upstream regulator of acid sphingomyelinase in apoptosis induced by inhibition of integrins αvβ3 and αvβ5.

    Directory of Open Access Journals (Sweden)

    Xiuhai Ren

    Full Text Available Inhibition of integrins αvβ3/αvβ5 by the cyclic function-blocking peptide, RGDfV (Arg-Gly-Asp-Phe-Val can induce apoptosis in both normal cells and tumor cells. We show that RGDfV induced apoptosis in ECV-304 carcinoma cells, increased activity and mRNA expression of acid sphingomyelinase (ASM, and increased ceramides C(16, C(18:0, C(24:0 and C(24:1 while decreasing the corresponding sphingomyelins. siRNA to ASM decreased RGDfV-induced apoptosis as measured by TUNEL, PARP cleavage, mitochondrial depolarization, and caspase-3 and caspase-8 activities, as well as by annexinV in a 3D collagen model. These findings indicate a causal role for ASM in RGDfV-induced apoptosis in ECV-304. We have shown that c-Abl, a non-receptor tyrosine kinase, also mediates RGDfV-induced apoptosis. However, c-Abl, has not been previously linked to ASM in any system. Here we show that STI-571 (imatinib, inhibitor of c-Abl inhibited RGDfV-induced ASM activity. Furthermore, STI-571 and c-Abl-siRNA both inhibited RGDfV-induced increase in ASM mRNA, but ASM-siRNA did not affect c-Abl phosphorylation or expression, supporting that c-Abl regulates the RGDfV-induced increase in ASM expression. These studies implicate ASM as a mediator of apoptosis induced by inhibition of integrins αvβ3/αvβ5, and for the first time place c-Abl as an upstream regulator of ASM expression and activity.

  14. Capsaicin sensitizes TRAIL-induced apoptosis through Sp1-mediated DR5 up-regulation: Involvement of Ca{sup 2+} influx

    Energy Technology Data Exchange (ETDEWEB)

    Moon, Dong-Oh [Department of Biology Education, Daegu University, Gyungsan, Gyeongbuk 712–714 (Korea, Republic of); Kang, Chang-Hee; Kang, Sang-Hyuck [Department of Marine Life Sciences, Jeju National University, Jeju 690–756 (Korea, Republic of); Choi, Yung-Hyun [Department of Biochemistry, College of Oriental Medicine, Dongeui University, Busan 614–054 (Korea, Republic of); Hyun, Jin-Won; Chang, Weon-Young; Kang, Hee-Kyoung; Koh, Young-Sang; Maeng, Young-Hee; Kim, Young-Ree [School of Medicine, Jeju National University, Jeju-si 690–756 (Korea, Republic of); Kim, Gi-Young, E-mail: immunkim@jejunu.ac.kr [Department of Marine Life Sciences, Jeju National University, Jeju 690–756 (Korea, Republic of)

    2012-02-15

    Although tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) induces apoptosis in various malignant cells, several cancers including human hepatocellular carcinoma (HCC) exhibit potent resistance to TRAIL-induced cell death. The aim of this study is to evaluate the anti-cancer potential of capsaicin in TRAIL-induced cancer cell death. As indicated by assays that measure phosphatidylserine exposure, mitochondrial activity and activation of caspases, capsaicin potentiated TRAIL-resistant cells to lead to cell death. In addition, we found that capsaicin induces the cell surface expression of TRAIL receptor DR5, but not DR4 through the activation Sp1 on its promoter region. Furthermore, we investigated that capsaicin-induced DR5 expression and apoptosis are inhibited by calcium chelator or inhibitors for calmodulin-dependent protein kinase. Taken together, our data suggest that capsaicin sensitizes TRAIL-mediated HCC cell apoptosis by DR5 up-regulation via calcium influx-dependent Sp1 activation. Highlights: ► Capsaicin sensitizes TRAIL-induced apoptosis through activation of caspases. ► Capsaicin induces expression of DR5 through Sp1 activation. ► Capsaicin activates calcium signaling pathway.

  15. 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

  16. Physapubescin selectively induces apoptosis in VHL-null renal cell carcinoma cells through down-regulation of HIF-2α and inhibits tumor growth.

    Science.gov (United States)

    Chen, Lixia; Xia, Guiyang; Qiu, Feng; Wu, Chunli; Denmon, Andria P; Zi, Xiaolin

    2016-01-01

    We have purified physapubescin, a predominant steroidal lactone, from medicinal plant Physalis pubescens L., commonly named as "hairy groundcherry" in English and "Deng-Long-Cao" in Chinese. Von Hippel-Lindau (VHL)-null 786-O, RCC4 and A498 Renal Cell Carcinoma (RCC) cell lines expressing high levels of Hypoxia Inducible Factor (HIF)-2α are more sensitive to physapubescin-mediated apoptosis and growth inhibitory effect than VHL wild-type Caki-2 and ACHN RCC cell lines. Restoration of VHL in RCC4 cells attenuated the growth inhibitory effect of physapubescin. Physapubescin decreases the expression of HIF-2α and increases the expression of CCAAT/enhancer-binding protein homologus protein (CHOP), which leads to up-regulation of death receptor 5 (DR5), activation of caspase-8 and -3, cleavage of poly (ADP-Ribose) polymerase (PARP) and apoptosis. Under hypoxia conditions, the apoptotic and growth inhibitory effects of physapubescin are further enhanced. Additionally, physapubescin synergizes with TNF-related apoptosis-inducing ligand (TRAIL) for markedly enhanced induction of apoptosis in VHL-null 786-O cells but not in VHL wild-type Caki-2 cells. Physapubescin significantly inhibited in vivo angiogenesis in the 786-O xenograft. Physapubescin as a novel agent for elimination of VHL-null RCC cells via apoptosis is warranted for further investigation. PMID:27581364

  17. Moxibustion down-regulates colonic epithelial cell apoptosis and repairs tight junctions in rats with Crohn's disease

    Institute of Scientific and Technical Information of China (English)

    Chun-Hui Bao; Lu-Yi Wu; Yin Shi; Huan-Gan Wu; Hui-Rong Liu; Rong Zhang; Li-Qing Yu; Jin-Hai Wang

    2011-01-01

    AIM: To investigate the effects of moxibustion on down-regulation of the colonic epithelial cell apoptosis and repair of the tight junctions in rats with Crohn's disease (CD).METHODS: Sixty male Sprague-Dawley rats were randomly divided into a normal control (NC) group, a model control (MC) group, an herbs-partitioned moxibustion (HPM) group, a mild-warm moxibustion (MWM) group and a salicylazosulphapyridine (SASP) group, with 12 rats in each group. The CD model rats were treated with trinitrobenzene sulphonic acid to induce intestinal inflammation. The rats in the HPM and MWM groups were treated at the Tianshu (ST25) and Qihai (CV6) acupoints once daily for 14 d, and the SASP group was fed SASP twice daily for 14 d. No additional treatment was given to the MC and NC groups. The microstructure of the colonic epithelium was observed under a transmission electron microscope, the transepithelial resistance was measured using a short-circuit current, colonic epithelial cell apoptosis was determined by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labelling assay, and the expression of occludin, claudin-1 and zonula occludens-l (ZO-1) in the colonic epithelial junction was determined by Western blotting and immunofluorescence staining.RESULTS: Compared with the MC group, the microstructure of the colonic epithelial barrier was significantly improved in rats treated with HPM, MWM or SASP, meanwhile, the current flow was reduced significantly, with values of 168.20 ± 6.14 vs 99.70 ± 3.13, 99.10 ± 4.28 and 120.30 ± 3.65 mA, respectively (P = 0.001). However, the HPM and MWM groups had higher current flow rates than the SASP group (99.70 ± 3.13, 99.10 ± 4.28 vs 120.30 ± 3.65 mA, P = 0.001). The number of the apoptotic colonic epithelial cells in HPM, MWM and SASP groups was largely reduced (61.5 ± 16.91 vs 15.5 ± 8.89, 14.8 ± 6.27 and 24.7 ± 9.68, respectively (P = 0.001); and the expression of occludin, claudin-1 and ZO-1 in the MWM and HPM

  18. Effect and mechanism of Vav3 gene to regulate inhibitor of apoptosis proteins in human gastri cancer cell line BGC823

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    Objective:hTe purpose of this study is to examine expression of Vav3 and effect and mechanism of Vav3 gene to regulate inhibitor of apoptosis proteins in human gastri cancer cell line BGC823 is also explored.Methods: hTe expression of Vav3 in gastric cancer tissues and cell lines were detected. Specific siRNA targeting Vav3 were designed, synthesized, and transfected into BGC823. The expression of Vav3 was detected by real-time quantitative PCR and western blot Cytoactive was measured with MTT assay Cell apoptosis rate were determined by lfow cytometry (FCM). hTe expressions of Survivin, c-IAP1, c-IAP2, XIAP, Livin and Caspase-3 were also determined.Results:Vav3 was signiifcantly up-regulated in gastric cancer tissues and gastric cancer cell line (both P<0.01). Cell activity of BGC823 was inhibited after Vav3-siRNA was transfected into BGC823 (P<0.05). hTe apoptosis rate was higher after Vav3-siRNA transfected into BGC823 (P<0.05). hTe expressions of Survivin, c-IAP1, c-IAP2, XIAP were lower in BGC823 after Vav3-siRNA tansfected (both P0.05), and no obviously change was found in Livin (P<0.05). Conclusion:Vav3 gene silencing effectively promoted gastric cancer cell apoptosis.

  19. The regulation of p53 up-regulated modulator of apoptosis by JNK/c-Jun pathway in β-amyloid-induced neuron death.

    Science.gov (United States)

    Akhter, Rumana; Sanphui, Priyankar; Das, Hrishita; Saha, Pampa; Biswas, Subhas Chandra

    2015-09-01

    Neuronal loss in selective areas of brain underlies the pathology of Alzheimer's disease (AD). Recent evidences place oligomeric β-amyloid (Aβ) central to the disease. However, mechanism of neuron death in response to Aβ remains elusive. Activation of the c-Jun N-terminal kinase (JNK) pathway and induction of the AP-1 transcription factor c-Jun are reported in AD. However, targets of JNK/c-Jun in Aβ-induced neuron death are mostly unknown. Our study shows that pro-apoptotic proteins, Bim (Bcl-2 interacting mediator of cell death) and Puma (p53 up-regulated modulator of apoptosis) are targets of c-Jun in Aβ-treated neurons. We demonstrate that the JNK/c-Jun pathway is activated, in cultures of cortical neurons following treatment with oligomeric Aβ and in AD transgenic mice, and that inhibition of this pathway by selective inhibitor blocks induction of Puma by Aβ. We also find that both JNK and p53 pathways co-operatively regulate Puma expression in Aβ-treated neurons. Moreover, we identified a novel AP1-binding site on rat puma gene which is necessary for direct binding of c-Jun with Puma promoter. Finally, we find that knocking down of c-Jun by siRNA provides significant protection from Aβ toxicity and that induction of Bim and Puma by Aβ in neurons requires c-Jun. Taken together, our results suggest that both Bim and Puma are target of c-Jun and elucidate the intricate regulation of Puma expression by JNK/c-Jun and p53 pathways in neurons upon Aβ toxicity. JNK/c-Jun pathway is shown to be activated in neurons of the Alzheimer's disease (AD) brain and plays a vital role in neuron death in AD models. However, downstream targets of c-Jun in this disease have not been thoroughly elucidated. Our study shows that two important pro-apoptotic proteins, Bim (Bcl-2 interacting mediator of cell death) and Puma (p53 up-regulated modulator of apoptosis) are targets of c-Jun in Aβ-treated neurons. We demonstrate that the JNK/c-jun pathway is activated, in cultures

  20. Naturally occurring mitochondrial-derived peptides are age-dependent regulators of apoptosis, insulin sensitivity, and inflammatory markers

    Science.gov (United States)

    Cobb, Laura J.; Lee, Changhan; Xiao, Jialin; Yen, Kelvin; Wong, Richard G.; Nakamura, Hiromi K.; Mehta, Hemal H.; Gao, Qinglei; Ashur, Carmel; Huffman, Derek M.; Wan, Junxiang; Muzumdar, Radhika; Barzilai, Nir; Cohen, Pinchas

    2016-01-01

    Mitochondria are key players in aging and in the pathogenesis of age-related diseases. Recent mitochondrial transcriptome analyses revealed the existence of multiple small mRNAs transcribed from mitochondrial DNA (mtDNA). Humanin (HN), a peptide encoded in the mtDNA 16S ribosomal RNA region, is a neuroprotective factor. An in silico search revealed six additional peptides in the same region of mtDNA as humanin; we named these peptides small humanin-like peptides (SHLPs). We identified the functional roles for these peptides and the potential mechanisms of action. The SHLPs differed in their ability to regulate cell viability in vitro. We focused on SHLP2 and SHLP3 because they shared similar protective effects with HN. Specifically, they significantly reduced apoptosis and the generation of reactive oxygen species, and improved mitochondrial metabolism in vitro. SHLP2 and SHLP3 also enhanced 3T3-L1 pre-adipocyte differentiation. Systemic hyperinsulinemic-euglycemic clamp studies showed that intracerebrally infused SHLP2 increased glucose uptake and suppressed hepatic glucose production, suggesting that it functions as an insulin sensitizer both peripherally and centrally. Similar to HN, the levels of circulating SHLP2 were found to decrease with age. These results suggest that mitochondria play critical roles in metabolism and survival through the synthesis of mitochondrial peptides, and provide new insights into mitochondrial biology with relevance to aging and human biology. PMID:27070352

  1. The regulation of thermal stress induced apoptosis in corals reveals high similarities in gene expression and function to higher animals

    Science.gov (United States)

    Kvitt, Hagit; Rosenfeld, Hanna; Tchernov, Dan

    2016-01-01

    Recent studies suggest that controlled apoptotic response provides an essential mechanism, enabling corals to respond to global warming and ocean acidification. However, the molecules involved and their functions are still unclear. To better characterize the apoptotic response in basal metazoans, we studied the expression profiles of selected genes that encode for putative pro- and anti-apoptotic mediators in the coral Stylophora pistillata under thermal stress and bleaching conditions. Upon thermal stress, as attested by the elevation of the heat-shock protein gene HSP70’s mRNA levels, the expression of all studied genes, including caspase, Bcl-2, Bax, APAF-1 and BI-1, peaked at 6–24 h of thermal stress (hts) and declined at 72 hts. Adversely, the expression levels of the survivin gene showed a shifted pattern, with elevation at 48–72 hts and a return to basal levels at 168 hts. Overall, we show the quantitative anti-apoptotic traits of the coral Bcl-2 protein, which resemble those of its mammalian counterpart. Altogether, our results highlight the similarities between apoptotic networks operating in simple metazoans and in higher animals and clearly demonstrate the activation of pro-cell survival regulators at early stages of the apoptotic response, contributing to the decline of apoptosis and the acclimation to chronic stress. PMID:27460544

  2. Curcumin inhibits cell growth and invasion and induces apoptosis through down-regulation of Skp2 in pancreatic cancer cells

    Science.gov (United States)

    Su, Jingna; Zhou, Xiuxia; Wang, Lixia; Yin, Xuyuan; Wang, Zhiwei

    2016-01-01

    Natural polyphenol compound curcumin has been found to exhibit its anticancer activity in a variety of human malignancies including pancreatic cancer (PC). However, the underlying mechanism has not been fully understood. Accumulating evidence has demonstrated that Skp2 (S-phase kinase associated protein 2) plays an oncogenic role in the development and progression of human cancers. In this study, we aim to explore the molecular basis of curcumin-induced cell growth inhibition in PC cells.Multiple methods such as CTG assay, Flow cytometry, clonogenic assay, wound healing assay, Transwell invasion assay, Western blotting, and transfection were performed to validate the oncogenic role of curcumin in PC cells. We found that curcumin suppressed cell growth, clonogenic potential, migration and invasion, and induced cell apoptosis and cell cycle arrest. Moreover, we observed thatover-expression of Skp2 significantly promoted cell growth, whereas down-regulation of Skp2 with siRNAs inhibited cell growth. The molecular basis of curcumin-mediated cell growth inhibition we identified is that curcumin significantly suppressed Skp2 expression and subsequently induced p21 expression. These findings suggested thattargeting Skp2 by curcumin could be a promising therapeutic strategy for the treatment of PC patients.

  3. The regulation of thermal stress induced apoptosis in corals reveals high similarities in gene expression and function to higher animals

    Science.gov (United States)

    Kvitt, Hagit; Rosenfeld, Hanna; Tchernov, Dan

    2016-07-01

    Recent studies suggest that controlled apoptotic response provides an essential mechanism, enabling corals to respond to global warming and ocean acidification. However, the molecules involved and their functions are still unclear. To better characterize the apoptotic response in basal metazoans, we studied the expression profiles of selected genes that encode for putative pro- and anti-apoptotic mediators in the coral Stylophora pistillata under thermal stress and bleaching conditions. Upon thermal stress, as attested by the elevation of the heat-shock protein gene HSP70’s mRNA levels, the expression of all studied genes, including caspase, Bcl-2, Bax, APAF-1 and BI-1, peaked at 6–24 h of thermal stress (hts) and declined at 72 hts. Adversely, the expression levels of the survivin gene showed a shifted pattern, with elevation at 48–72 hts and a return to basal levels at 168 hts. Overall, we show the quantitative anti-apoptotic traits of the coral Bcl-2 protein, which resemble those of its mammalian counterpart. Altogether, our results highlight the similarities between apoptotic networks operating in simple metazoans and in higher animals and clearly demonstrate the activation of pro-cell survival regulators at early stages of the apoptotic response, contributing to the decline of apoptosis and the acclimation to chronic stress.

  4. The regulation of thermal stress induced apoptosis in corals reveals high similarities in gene expression and function to higher animals.

    Science.gov (United States)

    Kvitt, Hagit; Rosenfeld, Hanna; Tchernov, Dan

    2016-01-01

    Recent studies suggest that controlled apoptotic response provides an essential mechanism, enabling corals to respond to global warming and ocean acidification. However, the molecules involved and their functions are still unclear. To better characterize the apoptotic response in basal metazoans, we studied the expression profiles of selected genes that encode for putative pro- and anti-apoptotic mediators in the coral Stylophora pistillata under thermal stress and bleaching conditions. Upon thermal stress, as attested by the elevation of the heat-shock protein gene HSP70's mRNA levels, the expression of all studied genes, including caspase, Bcl-2, Bax, APAF-1 and BI-1, peaked at 6-24 h of thermal stress (hts) and declined at 72 hts. Adversely, the expression levels of the survivin gene showed a shifted pattern, with elevation at 48-72 hts and a return to basal levels at 168 hts. Overall, we show the quantitative anti-apoptotic traits of the coral Bcl-2 protein, which resemble those of its mammalian counterpart. Altogether, our results highlight the similarities between apoptotic networks operating in simple metazoans and in higher animals and clearly demonstrate the activation of pro-cell survival regulators at early stages of the apoptotic response, contributing to the decline of apoptosis and the acclimation to chronic stress. PMID:27460544

  5. Characterization of the effects of cyclooxygenase-2 inhibition in the regulation of apoptosis in human small and non-small cell lung cancer cell lines.

    LENUS (Irish Health Repository)

    Alam, Mahmood

    2012-02-03

    BACKGROUND: Cyclooxygenase-2 enzyme (COX-2) is overexpressed in human non-small cell lung cancer (NSCLC) but is not expressed in small cell lung cancer. Selective COX-2 inhibitors have been shown to induce apoptosis in NSCLC cells, an effect which is associated with the regulation of intracellular MAP kinase (MAPK) signal pathways. Our aims were to characterize the effects of COX-2 inhibition by rofecoxib on apoptosis in human NSCLC and small cell lung cancer cell lines. METHODS: The human NSCLC cell line NCI-H2126 and small cell lung cancer cell line DMS-79 were used. Constitutive COX-2 protein levels were first determined by Western blot test. Levels of apoptosis were evaluated by using propidium iodide staining on FACScan analysis after incubation of NCI-H2126 and DMS-79 with p38 MAPK inhibitor SB202190 (25 ?microM), NF-kappaB inhibitor SN50 (75 microg\\/mL), and rofecoxib at 100 and 250 microM. All statistical analysis was performed by analysis of variance. RESULTS: Western blot test confirmed the presence of COX-2 enzyme in NCI-H2126 and absence in DMS-79. Interestingly, rofecoxib treatment demonstrated a dose-dependent increase in apoptosis in both cell lines. Given this finding, the effect of rofecoxib on NF-kappaB and p38 MAPK pathways was also examined. Apoptosis in both cell lines was unaltered by SN50, either alone or in combination with rofecoxib. A similar phenomenon was observed in NCI-H2126 cells treated with SB202190, either alone or in combination with rofecoxib. In contrast, p38 MAPK inhibition greatly upregulated DMS-79 apoptosis in a manner that was unaltered by the addition of rofecoxib. CONCLUSIONS: Rofecoxib led to a dose-dependent increase in apoptosis in both tumor cell lines. This effect occurred independently of COX-2, NF-kappaB, and p38 MAPK pathways in DMS-79 cells. As such, rofecoxib must act on alternative pathways to regulate apoptosis in human small cell lung cancer cells.

  6. TG-interacting factor transcriptionally induced by AKT/FOXO3A is a negative regulator that antagonizes arsenic trioxide-induced cancer cell apoptosis

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Zi-Miao; Tseng, Hong-Yu; Cheng, Ya-Ling [Department of Medical Laboratory Science and Biotechnology, College of Medicine, National Cheng Kung University, Tainan 701, Taiwan (China); Yeh, Bi-Wen [Department of Medical Laboratory Science and Biotechnology, College of Medicine, National Cheng Kung University, Tainan 701, Taiwan (China); Department of Urology, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan (China); Department of Urology, School of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan (China); Wu, Wen-Jeng [Department of Urology, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan (China); Department of Urology, School of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan (China); Huang, Huei-Sheng, E-mail: huanghs@mail.ncku.edu.tw [Department of Medical Laboratory Science and Biotechnology, College of Medicine, National Cheng Kung University, Tainan 701, Taiwan (China)

    2015-05-15

    Arsenic trioxide (ATO) is a multi-target drug approved by the Food and Drug Administration as the first-line chemotherapeutic agent for the treatment of acute promyelocytic leukemia. In addition, several clinical trials are being conducted with arsenic-based drugs for the treatment of other hematological malignancies and solid tumors. However, ATO's modest clinical efficacy on some cancers, and potential toxic effects on humans have been reported. Determining how best to reduce these adverse effects while increasing its therapeutic efficacy is obviously a critical issue. Previously, we demonstrated that the JNK-induced complex formation of phosphorylated c-Jun and TG-interacting factor (TGIF) antagonizes ERK-induced cyclin-dependent kinase inhibitor CDKN1A (p21{sup WAF1/CIP1}) expression and resultant apoptosis in response to ATO in A431 cells. Surprisingly, at low-concentrations (0.1–0.2 μM), ATO increased cellular proliferation, migration and invasion, involving TGIF expression, however, at high-concentrations (5–20 μM), ATO induced cell apoptosis. Using a promoter analysis, TGIF was transcriptionally regulated by ATO at the FOXO3A binding site (− 1486 to − 1479 bp) via the c-Src/EGFR/AKT pathway. Stable overexpression of TGIF promoted advancing the cell cycle into the S phase, and attenuated 20 μM ATO-induced apoptosis. Furthermore, blockage of the AKT pathway enhanced ATO-induced CDKN1A expression and resultant apoptosis in cancer cells, but overexpression of AKT1 inhibited CDKN1A expression. Therefore, we suggest that TGIF is transcriptionally regulated by the c-Src/EGFR/AKT pathway, which plays a role as a negative regulator in antagonizing ATO-induced CDKN1A expression and resultant apoptosis. Suppression of these antagonistic effects might be a promising therapeutic strategy toward improving clinical efficacy of ATO. - Highlights: • ATO-induced biphasic survival responses of cancer cells depend on low- or high-concentrations. • TGIF

  7. Induction of apoptosis by the retinoid inducible growth regulator RIG1 depends on the NC motif in HtTA cervical cancer cells

    Directory of Open Access Journals (Sweden)

    Lin Su-Ching

    2009-02-01

    Full Text Available Abstract Background Retinoid-inducible gene 1 (RIG1, also known as tazarotene-induced gene 3 or retinoic-acid receptor responder 3, is a growth regulator, which induces apoptosis and differentiation. RIG1 is classified into the NC protein family. This study investigated functional domains and critical amino acids associated with RIG1-mediated cell death and apoptosis. Results Using enhanced green fluorescence protein (EGFP-tagged RIG1 variants, RIG1 proteins with deletion at the NC domain significantly decreased cell death induced by RIG1, and fusion variants containing only the NC domain significantly induced apoptosis of HtTA cervical cancer cells. The EGFP-RIG1-induced apoptosis was significantly decreased in cells expressing N112C113 motif double- (NC→FG or triple- (NCR→FGE mutated RIG1 variants. Using dodecapeptides, nuclear localization and profound cell death was observed in HtTA cells expressing wild type RIG1111–123 or Leu121-mutated RIG1111–123:L→ C peptide, but peptides double- or triple-mutated at the NC motif alone, RIG1111–123:NC→FG or RIG1111–123:NCR→FGE, were cytoplasmically localized and did not induce apoptosis. The RIG1111–123 also induced apoptosis of A2058 melanoma cells but not normal human fibroblasts. Conclusion The NC domain, especially the NC motif, plays the major role in RIG1-mediated pro-apoptotic activity. The RIG1111–123 dodecapeptide exhibited strong pro-apoptotic activity and has potential as an anticancer drug.

  8. Up-regulation of hypoxia inducible factor-1α by cobalt chloride correlates with proliferation and apoptosis in PC-2 cells

    Directory of Open Access Journals (Sweden)

    Dai Zhi-Jun

    2012-03-01

    Full Text Available Abstract Background The exact mechanism of the effects of hypoxia on the proliferation and apoptosis in carcinoma cells is still conflicting. This study investigated the variation of hypoxia-inducible factor-1α(HIF-1α expression and the apoptosis effect of hypoxia stimulated by cobalt chloride (CoCl2 in pancreatic cancer PC-2 cells. Methods PC-2 cells were cultured with different concentration (50-200 μmol/L of CoCl2 after 24-120 hours to simulate hypoxia in vitro. The proliferation of PC-2 cells was examined by MTT assay. The cellular morphology of PC-2 cells were observed by light inverted microscope and transmission electron microscope(EM. The expression of HIF-1α on mRNA and protein level was measured by semi-quantitive RT-PCR and Western blot analysis. Apoptosis of PC-2 cells were demonstrated by flow cytometry with Annexin V-FITC/PI double staining. Results MTT assay showed that the proliferation of PC-2 cells were stimulated in the first 72 h, while after treated over 72 h, a dose- dependent inhibition of cell growth could be observed. By using transmission electron microscope, swollen chondrosomes, accumulated chromatin under the nuclear membrane and apoptosis bodies were observed. Flow cytometer(FCM analysis showed the apoptosis rate was correlated with the dosage of CoCl2. RT-PCR and Western blot analysis indicated that hypoxia could up-regulate the expression of HIF-1α on both mRNA and protein levels. Conclusion Hypoxic microenvironment stimulated by CoCl2 could effectively induce apoptosis and influence cell proliferation in PC-2 cells, the mechanism could be related to up-expression of HIF-1α.

  9. miR-122 regulates p53/Akt signalling and the chemotherapy-induced apoptosis in cutaneous T-cell lymphoma.

    Directory of Open Access Journals (Sweden)

    Valentina Manfè

    Full Text Available Advanced cutaneous T-cell lymphoma (CTCL is resistant to chemotherapy and presents a major area of medical need. In view of the known role of microRNAs (miRNAs in the regulation of cellular signalling, we aimed to identify the functionally important miRNA species, which regulate apoptosis in CTCL. Using a recently established model in which apoptosis of CTCL cell lines is induced by Notch-1 inhibition by γ-secretase inhibitors (GSIs, we found that miR-122 was significantly increased in the apoptotic cells. miR-122 up-regulation was not specific for GSI-1 but was also seen during apoptosis induced by chemotherapies including doxorubicin and proteasome blockers (bortezomib, MG132. miR-122 was not expressed in quiescent T-cells, but was detectable in CTCL: in lesional skin in mycosis fungoides and in Sézary cells purified from peripheral blood. In situ hybridization results showed that miR-122 was expressed in the malignant T-cell infiltrate and increased in the advanced stage mycosis fungoides. Surprisingly, miR-122 overexpression decreased the sensitivity to the chemotherapy-induced apoptosis via a signaling circuit involving the activation of Akt and inhibition of p53. We have also shown that induction of miR-122 occurred via p53 and that p53 post-transcriptionally up-regulated miR-122. miR-122 is thus an amplifier of the antiapoptotic Akt/p53 circuit and it is conceivable that a pharmacological intervention in this pathway may provide basis for novel therapies for CTCL.

  10. Effect of normothermic liver ischemic preconditioning on the expression of apoptosis-regulating genes C-jun and Bcl-XL in rats

    Institute of Scientific and Technical Information of China (English)

    Guo-Huang Hu; Xin-Sheng Lü

    2005-01-01

    AIM: To explore the expression of apoptosis-regulatinggenes C-jun and Bcl-XL after normothermic liver ischemic preconditioning and its protective effect on hepatocytes in the rat.METHODS: Wistar rats are randomly divided into sham operation group (S group, n = 10), ischemic reperfusion group (IR group, n = 10) and ischemic preconditioning group (IP group, n = 10). After dissection of the hepatoduodenal ligament in S group, and after 30-min reperfusion in IR group and in IP group, the samples of liver tissue were taken for studying the hepatocellular apoptosis, theexpressions of C-jun mRNA, Bcl-XL mRNA and their proteins, and morphologic changes at 0, 3, 6, 20 h. Meanwhile the venous blood samples were drawn at 3, 6 and 20 h for testing ALT, AST and LDH.RESULTS: The levels of ALT, AST and LDH in IR group and IP group were significantly higher than those in S group. Hepatocellular apoptosis was significantly increased in both IR group and IP group, especially in IR group.Expressions of C-jun mRNA and protein were significantly increased in IR group compared with those in both IP group and S group, but no significant difference between IP group and S group (P>0.05). Expressions of Bcl-XL mRNA and protein in IR group and S group were not significant (P>0.05), but were significantly increased in IP group compared with those in both S group and IR group. Patch necrosis of hepatocytes because of severe injury could be seen in IR group microscopically, and the ultrastructural changes were irreversible. Meanwhile in IP group, no hepatocellular necrosis occurred, and the ultrastructural changes were reversible because of mild injury. CONCLUSION: (1) IP can protect the rat liver from normothermic IR injury by modulation of the expressionof apoptosis-regulating genes C-jun and Bcl-XL; (2) IR injury may activate the apoptosis of hepatocytes by increasing the expression of apoptosis-inducing gene C-jun; (3) IP may prohibit the apoptosis of hepatocytes by increasing the

  11. Matrine inhibits diethylnitrosamine-induced HCC proliferation in rats through inducing apoptosis via p53, Bax-dependent caspase-3 activation pathway and down-regulating MLCK overexpression.

    Science.gov (United States)

    Zhang, Xiaolin; Yu, Hao

    2016-01-01

    The proliferation of hepatocellular carcinoma (HCC) cells is one of the leading causes of liver cancer mortality in humans. The inhibiting effects of matrine on HCC cell proliferation have been studied, but the mechanism of that inhibition has not been fully elucidated. Since, apoptosis plays an important role in HCC cell proliferation. We examined the apoptosis-inducing effect of matrine on tumor cells. Western blot analysis of p53, Bax, cleaved caspase-3 and myosin light chain kinase (MLCK) revealed that matrine induced tumor cell apoptosis by controlling anoikis. It activated p53, Bax-dependent caspase-3 and blocked the ECM-integrin mediated cell survival pathway through down-regulating MLCK over-expression in the liver of rats with diethyl nitrosamine (DENA)-induced HCC. Our results suggest that matrine can inhibit the proliferation of HCC cells through inducing tumor cell apoptosis via activation of the p53 pathway and inhibition of MLCK overexpression. Matrine may thus be used as a potentially promising reagent to inhibit HCC cell proliferation and MLCK may be a novel target for the treatment of HCC. PMID:27642320

  12. Roscovitine-induced apoptosis in neutrophils and neutrophil progenitors is regulated by the Bcl-2-family members Bim, Puma, Noxa and Mcl-1.

    Directory of Open Access Journals (Sweden)

    Sanjivan Gautam

    Full Text Available Neutrophil granulocyte (neutrophil apoptosis plays a key role in determining inflammation in infectious and non-infectious settings. Recent work has shown that inhibitors of cyclin-dependent kinases (cdk such as roscovitine can potently induce neutrophil apoptosis and reduce inflammation. Using a conditional Hoxb8-expression system we tested the participation of Bcl-2-family proteins to roscovitine-induced apoptosis in mouse neutrophils and in neutrophil progenitor cells. Bcl-2 strongly protected against roscovitine-induced apoptosis in neutrophils. The isolated loss of either Bim or noxa provided significant, partial protection while protection through combined loss of Bim and noxa or Bim and Puma was only slightly greater than this individual loss. The only substantial change in protein levels observed was the loss of Mcl-1, which was not transcriptional and was inhibited by proteasome blockade. In progenitor cells there was no protection by the loss of Bim alone but substantial protection by the loss of both Bim and Puma; surprisingly, strongest protection was seen by the isolated loss of noxa. The pattern of protein expression and Mcl-1-regulation in progenitor cells was very similar to the one observed in differentiated neutrophils. In addition, roscovitine strongly inhibited proliferation in progenitor cells, associated with an accumulation of cells in G2/M-phase.

  13. Arctigenin, a dietary phytoestrogen, induces apoptosis of estrogen receptor-negative breast cancer cells through the ROS/p38 MAPK pathway and epigenetic regulation.

    Science.gov (United States)

    Hsieh, Chia-Jung; Kuo, Po-Lin; Hsu, Ying-Chan; Huang, Ya-Fang; Tsai, Eing-Mei; Hsu, Ya-Ling

    2014-02-01

    This study investigates the anticancer effect of arctigenin (ATG), a natural lignan product of Arctium lappa L., in human breast cancer MDA-MB-231 cells. Results indicate that ATG inhibits MDA-MB-231 cell growth by inducing apoptosis in vitro and in vivo. ATG triggers the mitochondrial caspase-independent pathways, as indicated by changes in Bax/Bcl-2 ratio, resulting in AIF and EndoG nuclear translocation. ATG increased cellular reactive oxygen species (ROS) production by increasing p22(phox)/NADPH oxidase 1 interaction and decreasing glutathione level. ATG clearly increases the activation of p38 MAPK, but not JNK and ERK1/2. Antioxidant EUK-8, a synthetic catalytic superoxide and hydrogen peroxide scavenger, significantly decreases ATG-mediated p38 activation and apoptosis. Blocking p38 with a specific inhibitor suppresses ATG-mediated Bcl-2 downregulation and apoptosis. Moreover, ATG activates ATF-2, a transcription factor activated by p38, and then upregulates histone H3K9 trimethylation in the Bcl-2 gene promoter region, resulting in Bcl-2 downregulation. Taken together, the results demonstrate that ATG induces apoptosis of MDA-MB-231 cells via the ROS/p38 MAPK pathway and epigenetic regulation of Bcl-2 by upregulation of histone H3K9 trimethylation. PMID:24140706

  14. Matrine-induced apoptosis of human nasopharyngeal carcinoma cells via in vitro vascular endothelial growth factor-A/extracellular signal-regulated kinase1/2 pathway inactivation.

    Science.gov (United States)

    Xie, M; He, G; Wang, R; Shi, S; Chen, J; Ye, Y; Xie, L; Yi, X; Tang, A

    2014-07-01

    Matrine, a main active extract from Sophora flavescens Ait, has been demonstrated to exert anticancer effects on various cancer cell lines, such as malignant melanoma, breast cancer, and lung cancer. However, it is currently unclear whether matrine could also elicit an inhibitory effect on growth of nasopharyngeal carcinoma (NPC), let alone the possible molecular mechanisms. Therefore, in a previous study, we investigated matrine-induced proliferation inhibition and apoptosis in NPC cells. It was shown that proliferation of human NPC cells (CNE1 and CNE2) was significantly diminished by matrine in a dose- and time-dependent manner, and apoptosis was induced in both 2 NPC cells, particularly in CNE2 cells. Moreover, the increased apoptosis rate in matrine-treated CNE2 cells confirmed the proapoptotic activity of matrine. We further found that matrine treatment dose- and time-dependently reduced the levels of vascular endothelial growth factor-A (VEGF-A), and inactivated extracellular signal-regulated kinase1/2 (ERK1/2), followed by increased expression of downstream target caspase-3. Overall, we conclude that matrine could induce apoptosis of human NPC cells via VEGF-A/ERK1/2 pathway, which supports the potential use of matrine in clinically treating NPC.

  15. Matrine inhibits diethylnitrosamine-induced HCC proliferation in rats through inducing apoptosis via p53, Bax-dependent caspase-3 activation pathway and down-regulating MLCK overexpression.

    Science.gov (United States)

    Zhang, Xiaolin; Yu, Hao

    2016-01-01

    The proliferation of hepatocellular carcinoma (HCC) cells is one of the leading causes of liver cancer mortality in humans. The inhibiting effects of matrine on HCC cell proliferation have been studied, but the mechanism of that inhibition has not been fully elucidated. Since, apoptosis plays an important role in HCC cell proliferation. We examined the apoptosis-inducing effect of matrine on tumor cells. Western blot analysis of p53, Bax, cleaved caspase-3 and myosin light chain kinase (MLCK) revealed that matrine induced tumor cell apoptosis by controlling anoikis. It activated p53, Bax-dependent caspase-3 and blocked the ECM-integrin mediated cell survival pathway through down-regulating MLCK over-expression in the liver of rats with diethyl nitrosamine (DENA)-induced HCC. Our results suggest that matrine can inhibit the proliferation of HCC cells through inducing tumor cell apoptosis via activation of the p53 pathway and inhibition of MLCK overexpression. Matrine may thus be used as a potentially promising reagent to inhibit HCC cell proliferation and MLCK may be a novel target for the treatment of HCC.

  16. Matrine inhibits diethylnitrosamine-induced HCC proliferation in rats through inducing apoptosis via p53, Bax-dependent caspase-3 activation pathway and down-regulating MLCK overexpression

    Science.gov (United States)

    Zhang, Xiaolin; Yu, Hao

    2016-01-01

    The proliferation of hepatocellular carcinoma (HCC) cells is one of the leading causes of liver cancer mortality in humans. The inhibiting effects of matrine on HCC cell proliferation have been studied, but the mechanism of that inhibition has not been fully elucidated. Since, apoptosis plays an important role in HCC cell proliferation. We examined the apoptosis-inducing effect of matrine on tumor cells. Western blot analysis of p53, Bax, cleaved caspase-3 and myosin light chain kinase (MLCK) revealed that matrine induced tumor cell apoptosis by controlling anoikis. It activated p53, Bax-dependent caspase-3 and blocked the ECM-integrin mediated cell survival pathway through down-regulating MLCK over-expression in the liver of rats with diethyl nitrosamine (DENA)-induced HCC. Our results suggest that matrine can inhibit the proliferation of HCC cells through inducing tumor cell apoptosis via activation of the p53 pathway and inhibition of MLCK overexpression. Matrine may thus be used as a potentially promising reagent to inhibit HCC cell proliferation and MLCK may be a novel target for the treatment of HCC. PMID:27642320

  17. Free cholesterol-induced macrophage apoptosis is mediated by inositol-requiring enzyme 1 alpha-regulated activation of Jun N-terminal kinase

    Institute of Scientific and Technical Information of China (English)

    Fangming Li; Yi Guo; Shenggang Sun; Xin Jiang; Bingshan Tang; Qizhang Wang; Ling Wang

    2008-01-01

    Macrophage death in advanced atherosclerotic lesions leads to iesional necrosis, possible plaque rupture, and acute vascular occlusion. A likely cause of macrophage death is the accumulation of free cholesterol (FC) leading to activation of endoplasmic reticulum (ER) stress-induced apoptosis.Inositol-requiring enzyme 1 alpha (IRE1α) is an integral membrane protein of the ER that is a key signaling step in cholesterol-induced apoptosis in macrophages, activated by stress in the ER. However, the role of IRE1α in the regulation of ER stress-induced macrophage death and the mechanism for this process are largely unclear.In this study,a cell culture model was used to explore the mechanisms involved in the ER stress pathway of FC-induced macrophage death.The results herein showed that FC loading of macrophages leads to an apoptotic response that is partially dependent on initiation by activation of IRE1α.Taken together,these results showed that the IRE1-apoptosis-signaling kinase 1-c-Jun NH2-terminal kinase cascade pathway was required in this process.Moreover,the data suggested a novel cellular mechanism for cholesterol-induced macrophage death in advanced atherosclerotic lesions.The critical function of this signaling cascade is indicated by prevention of ER stress-induced apoptosis after inhibition of IRE1α,or c-Jun NH2-terminal kinase.

  18. Poncirin Induces Apoptosis in AGS Human Gastric Cancer Cells through Extrinsic Apoptotic Pathway by up-Regulation of Fas Ligand

    Directory of Open Access Journals (Sweden)

    Venu Venkatarame Gowda Saralamma

    2015-09-01

    Full Text Available Poncirin, a natural bitter flavanone glycoside abundantly present in many species of citrus fruits, has various biological benefits such as anti-oxidant, anti-microbial, anti-inflammatory and anti-cancer activities. The anti-cancer mechanism of Poncirin remains elusive to date. In this study, we investigated the anti-cancer effects of Poncirin in AGS human gastric cancer cells (gastric adenocarcinoma. The results revealed that Poncirin could inhibit the proliferation of AGS cells in a dose-dependent manner. It was observed Poncirin induced accumulation of sub-G1 DNA content, apoptotic cell population, apoptotic bodies, chromatin condensation, and DNA fragmentation in a dose-dependent manner in AGS cells. The expression of Fas Ligand (FasL protein was up-regulated dose dependently in Poncirin-treated AGS cells Moreover, Poncirin in AGS cells induced activation of Caspase-8 and -3, and subsequent cleavage of poly(ADP-ribose polymerase (PARP. Inhibitor studies’ results confirm that the induction of caspase-dependent apoptotic cell death in Poncirin-treated AGS cells was led by the Fas death receptor. Interestingly, Poncirin did not show any effect on mitochondrial membrane potential (ΔΨm, pro-apoptotic proteins (Bax and Bak and anti-apoptotic protein (Bcl-xL in AGS-treated cells followed by no activation in the mitochondrial apoptotic protein caspase-9. This result suggests that the mitochondrial-mediated pathway is not involved in Poncirin-induced cell death in gastric cancer. These findings suggest that Poncirin has a potential anti-cancer effect via extrinsic pathway-mediated apoptosis, possibly making it a strong therapeutic agent for human gastric cancer.

  19. Curcumin Promoted the Apoptosis of Cisplain-resistant Human Lung Carcinoma Cells A549/DDP through Down-regulating miR-186*

    Directory of Open Access Journals (Sweden)

    Jian ZHANG

    2010-04-01

    Full Text Available Background and objective Curcumin, a natural compound, is derived from the rthizom of Curcuma longa. In vitro and in vivo preclinical studies have shown its anti-inflammatory, antioxidant, anticancer activities and so on. miR-186*, which was found by microarray technology, was highly expressed in lung carcinoma cells A549/DDP. The aim of this study is to illustrate whether Curcumin could promote the apoptosis of A549/DDP cells through regulating the expression of miR-186*. Methods An oligonucleotide microarray chip was used to profile microRNA (miRNA expressions in A549/DDP cells treated with and without Curcumin. The significantly differentially expressed miRNA, which was selected from microarray chip, validated by quantitative real-time PCR. Ultimately, the remarkably expressed miRNA modulated the apoptosis assaying by flow cytometry expriments and the survival rate was measured by MTT method. Results The microarray chip results demonstrated: Curcumin altered the expression level of miRNAs compared with untreated control in A549/DDP cell line, miR-186* was significantly down-regulated after Curcumin treatment, which confirmed by quantitative real-time PCR. Downregulation of miR-186* expression by curcumin elevated the apoptosis, and the survival rate of A549/DDP cells decreased; but up-regulation of miR-186* expression by transfection its mimics restrained the apoptosis, the survival rate of A549/DDP cells increased, which were assayed by flow cytometry expriments and MTT method. Conclusion Modulation of miRNAs expression may be an important mechanism underlying the biological roles of Curcumin.

  20. Down-regulation of miR-20a-5p triggers cell apoptosis to facilitate mycobacterial clearance through targeting JNK2 in human macrophages.

    Science.gov (United States)

    Zhang, Guoliang; Liu, Xi; Wang, Wenfei; Cai, Yi; Li, Shaoyuan; Chen, Qi; Liao, Mingfeng; Zhang, Mingxia; Zeng, Gucheng; Zhou, Boping; Feng, Carl G; Chen, Xinchun

    2016-09-16

    Induction of cell apoptosis is one of the major host defense mechanisms through which macrophages control Mycobacterium tuberculosis (Mtb) infection. However, the mechanisms underlying macrophage apoptosis triggered by Mtb infection are still largely unknown. In this study, a microarray profiling survey revealed 14 miRNAs were down-regulated in CD14+ monocytes from active pulmonary tuberculosis patients, and only the reduction of miR-20a-5p could be reversed after successful anti-tuberculosis treatment. Validation of miR-20a-5p expression was confirmed using real time qPCR. Moreover, miR-20a-5p expression also decreased in differentiated THP-1 macrophages after mycobacterial infection in vitro. Functional assays through forced or inhibited expression of miR-20a-5p in THP-1 macrophages demonstrated that miR-20a-5p functioned as a negative regulator of mycobacterial-triggered apoptosis. Importantly, inhibition of miR-20a-5p expression resulted in more efficient mycobacterial clearance from infected THP-1 macrophages while miR-20a-5p overexpression promoted mycobacterial survival. Mechanistically, miR-20a-5p was demonstrated to regulate Bim expression in a JNK2-dependent manner, unlike Bcl2, and luciferase assay showed JNK2 was a novel direct target of miR-20a-5p. Together, our findings indicate that downregulation of miR-20a-5p triggers macrophage apoptosis as a novel mechanism for host defense against mycobacterial infection. PMID:27494776

  1. MicroRNA-134 regulates lung cancer cell H69 growth and apoptosis by targeting WWOX gene and suppressing the ERK1/2 signaling pathway

    International Nuclear Information System (INIS)

    MicroRNAs have been shown to act as crucial modulators during carcinogenesis. Recent studies have implied that miR-134 expression associated with epithelial-to-mesenchymal transition phenotype and invasive potential of NSCLC cells. Our study investigated the pathogenic implications of miR-134 in small cell lung cancer (SCLC). Overexpression or inhibition MiR-134 expression by miR-134 mimics or miR-134 inhibitors (anti-miR-134) in SCLC cell lines was detected using qRT-PCR. Lactate dehydrogenase (LDH) assay, MTT assays and flow cytometry were performed in order to clarify the growth and apoptosis of SCLC cells which had been transfected with miR-134 mimics or anti-miR-134. WWOX expression in H69 cells was detected by qRT-PCR and western blot, respectively. The results showed that overexpression miR-134 was significantly promoting SCLC cells growth and inhibit its apoptosis. In addition, reduced miR-134 expression was significantly correlated with cell growth inhibition and apoptosis promotion. Furthermore, transfection of miR-134 mimics into the SCLC cells markedly down-regulated the level of WWOX, whereas, anti-miR-134 up-regulated WWOX expression. We also found that overexpression WWOX attenuate miR-134 induced H69 cells growth, and promote cell apoptosis. Moreover, miR-134 promoted cell proliferation and inhibit apoptosis via the activation of ERK1/2 pathway. These findings suggest that miR-134 may be an ideal diagnostic and prognostic marker, and may be attributed to the molecular therapy of SCLC. - Highlights: • MiR-134 play roles in small cell lung cancer cell growth and apoptosis. • MiR-134 negative regulated the level of WWOX in H69 cells. • WWOX overexpression attenuate miR-134 induced H69 cells growth. • MiR-134 promotes cell growth via the activation of ERK1/2 pathway

  2. MicroRNA-134 regulates lung cancer cell H69 growth and apoptosis by targeting WWOX gene and suppressing the ERK1/2 signaling pathway

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Tianjun [Respiratory Department, The First Affiliated Hospital, Xi' an Jiaotong University, No. 277, Yanta West Road, Xi' an, Shaanxi (China); Gao, Fei [Ultrasound Department, Hua-shan Central Hospital of Xi' an, No. 8, Wanshou Middle Road, Xi' an, Shaanxi (China); Feng, Sifang; Yang, Tian [Respiratory Department, The First Affiliated Hospital, Xi' an Jiaotong University, No. 277, Yanta West Road, Xi' an, Shaanxi (China); Chen, Mingwei, E-mail: mingweichenxian@163.com [Respiratory Department, The First Affiliated Hospital, Xi' an Jiaotong University, No. 277, Yanta West Road, Xi' an, Shaanxi (China)

    2015-08-28

    MicroRNAs have been shown to act as crucial modulators during carcinogenesis. Recent studies have implied that miR-134 expression associated with epithelial-to-mesenchymal transition phenotype and invasive potential of NSCLC cells. Our study investigated the pathogenic implications of miR-134 in small cell lung cancer (SCLC). Overexpression or inhibition MiR-134 expression by miR-134 mimics or miR-134 inhibitors (anti-miR-134) in SCLC cell lines was detected using qRT-PCR. Lactate dehydrogenase (LDH) assay, MTT assays and flow cytometry were performed in order to clarify the growth and apoptosis of SCLC cells which had been transfected with miR-134 mimics or anti-miR-134. WWOX expression in H69 cells was detected by qRT-PCR and western blot, respectively. The results showed that overexpression miR-134 was significantly promoting SCLC cells growth and inhibit its apoptosis. In addition, reduced miR-134 expression was significantly correlated with cell growth inhibition and apoptosis promotion. Furthermore, transfection of miR-134 mimics into the SCLC cells markedly down-regulated the level of WWOX, whereas, anti-miR-134 up-regulated WWOX expression. We also found that overexpression WWOX attenuate miR-134 induced H69 cells growth, and promote cell apoptosis. Moreover, miR-134 promoted cell proliferation and inhibit apoptosis via the activation of ERK1/2 pathway. These findings suggest that miR-134 may be an ideal diagnostic and prognostic marker, and may be attributed to the molecular therapy of SCLC. - Highlights: • MiR-134 play roles in small cell lung cancer cell growth and apoptosis. • MiR-134 negative regulated the level of WWOX in H69 cells. • WWOX overexpression attenuate miR-134 induced H69 cells growth. • MiR-134 promotes cell growth via the activation of ERK1/2 pathway.

  3. Opposing roles of TGF-β and EGF in the regulation of TRAIL-induced apoptosis in human breast epithelial cells.

    Science.gov (United States)

    Cano-González, Ana; López-Rivas, Abelardo

    2016-08-01

    Transforming growth factor-beta (TGF-β) induces the epithelial to mesenchymal transition (EMT) in breast epithelial cells and plays an important role in mammary morphogenesis and breast cancer. In non-transformed breast epithelial cells TGF-β antagonizes epidermal growth factor (EGF) action and induces growth inhibition. Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) has been reported to participate in lumen formation during morphogenesis of human breast epithelial cells. Our previous work indicated that sensitivity of human breast epithelial cells to TRAIL can be modulated through the activation of the epidermal growth factor receptor-1 (EGFR). Here, we show that TGF-β opposes EGF-mediated sensitization to TRAIL-induced caspase-8 activation and apoptosis in non-transformed breast epithelial cells. Death-inducing signalling complex (DISC) formation by TRAIL was significantly reduced in cells treated with TGF-β. TGF-β treatment activates cytoprotective autophagy and down-regulates TRAIL-R2 expression at the cell surface by promoting the intracellular accumulation of this receptor. Lastly, we demonstrate that EMT is not involved in the inhibitory effect of TGF-β on apoptosis by TRAIL. Together, the data reveal a fine regulation by EGF and TGF-β of sensitivity of human breast epithelial cells to TRAIL which may be relevant during morphogenesis. PMID:27208428

  4. Prostaglandin EP2 receptor signaling protects human trabecular meshwork cells from apoptosis induced by ER stress through down-regulation of p53.

    Science.gov (United States)

    Kalouche, Georges; Boucher, Céline; Coste, Annick; Debussche, Laurent; Orsini, Cécile; Baudouin, Christophe; Debeir, Thomas; Vigé, Xavier; Rostène, William

    2016-09-01

    E-prostanoid receptor subtype 2 (EP2) agonists are currently under clinical development as hypotensive agents for the treatment of ocular hypertension. However, the effects of EP2 receptor agonists on trabecular meshwork (TM) alterations leading to primary open-angle glaucoma (POAG) are still unknown. Here, we evaluated whether EP2 receptor activation exhibits protective functions on TM cell death induced by endoplasmic reticulum (ER) stress. We show that the EP2 receptor agonist butaprost protects TM cell death mediated by the ER stress inducer tunicamycin through a cyclic AMP (cAMP)-dependent mechanism, but independent of the classical cAMP sensors, protein kinase A and exchange proteins activated by cAMP. The ER stress-induced intrinsic apoptosis inhibited by the EP2 receptor agonist was correlated with a decreased accumulation of the cellular stress sensor p53. In addition, p53 down-regulation was associated with inhibition of its transcriptional activity, which led to decreased expression of the pro-apoptotic p53-upregulated modulator of apoptosis (PUMA). The stabilization of p53 by nutlin-3a abolished butaprost-mediated cell death protection. In conclusion, we showed that EP2 receptor activation protects against ER stress-dependent mitochondrial apoptosis through down-regulation of p53. The specific inhibition of this pathway could reduce TM alterations observed in POAG patients. PMID:27321910

  5. Juglone, isolated from Juglans mandshurica Maxim, induces apoptosis via down-regulation of AR expression in human prostate cancer LNCaP cells.

    Science.gov (United States)

    Xu, Huali; Yu, Xiaofeng; Qu, Shaochun; Sui, Dayun

    2013-06-15

    Juglone is a natural compound which has been isolated from Juglans mandshurica Maxim. Recent studies have shown that juglone had various pharmacological effects such as anti-viral, anti-bacterial and anti-cancer. However, its anti-cancer activity on human prostate cancer LNCaP cell has not been examined. Thus, the current study was designed to elucidate the molecular mechanism of apoptosis induced by juglone in androgen-sensitive prostate cancer LNCaP cells. MTT assay was performed to examine the anti-proliferative effect of juglone. Occurrence of apoptosis was detected by Hoechst 33342 staining and flow cytometry in LNCaP cells treated with juglone for 24h. The result shown that juglone inhibited the growth of LNCaP cells in a dose-dependent manner. Morphological changes of apoptotic body formation after juglone treatment were observed by Hoechst 33342 staining. This apoptotic induction was associated with loss of mitochondrial membrane potential, and caspase-3, -9 activation. Moreover, we found that juglone significantly inhibited the expression levels of androgen receptor (AR) and prostate-specific antigen (PSA) in a dose-dependent manner, as well as abrogated up-regulation of AR and PSA genes with and/or without dihydrotestosterone (DHT). Take together, our results demonstrated that juglone might induce the apoptosis in LNCaP cell via down-regulation of AR expression. Therefore, our results indicated that juglone may be a potential candidate of drug for androgen-sensitive prostate cancer.

  6. Opposing roles of TGF-β and EGF in the regulation of TRAIL-induced apoptosis in human breast epithelial cells.

    Science.gov (United States)

    Cano-González, Ana; López-Rivas, Abelardo

    2016-08-01

    Transforming growth factor-beta (TGF-β) induces the epithelial to mesenchymal transition (EMT) in breast epithelial cells and plays an important role in mammary morphogenesis and breast cancer. In non-transformed breast epithelial cells TGF-β antagonizes epidermal growth factor (EGF) action and induces growth inhibition. Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) has been reported to participate in lumen formation during morphogenesis of human breast epithelial cells. Our previous work indicated that sensitivity of human breast epithelial cells to TRAIL can be modulated through the activation of the epidermal growth factor receptor-1 (EGFR). Here, we show that TGF-β opposes EGF-mediated sensitization to TRAIL-induced caspase-8 activation and apoptosis in non-transformed breast epithelial cells. Death-inducing signalling complex (DISC) formation by TRAIL was significantly reduced in cells treated with TGF-β. TGF-β treatment activates cytoprotective autophagy and down-regulates TRAIL-R2 expression at the cell surface by promoting the intracellular accumulation of this receptor. Lastly, we demonstrate that EMT is not involved in the inhibitory effect of TGF-β on apoptosis by TRAIL. Together, the data reveal a fine regulation by EGF and TGF-β of sensitivity of human breast epithelial cells to TRAIL which may be relevant during morphogenesis.

  7. 6-Shogaol enhances renal carcinoma Caki cells to TRAIL-induced apoptosis through reactive oxygen species-mediated cytochrome c release and down-regulation of c-FLIP(L) expression.

    Science.gov (United States)

    Han, Min Ae; Woo, Seon Min; Min, Kyoung-jin; Kim, Shin; Park, Jong-Wook; Kim, Dong Eun; Kim, Sang Hyun; Choi, Yung Hyun; Kwon, Taeg Kyu

    2015-02-25

    6-Shogaol, a potent bioactive compound in ginger (Zingiber officinale Roscoe), has been reported for anti-inflammatory and anti-cancer activity. In this study, we investigated the effect of 6-shogaol to enhance tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)-mediated apoptosis. The combined treatment with 6-shogaol and TRAIL markedly induces apoptosis in various cancer cells (renal carcinoma Caki cells, breast carcinoma MDA-MB-231 cells and glioma U118MG cells), but not in normal mesangial cells and normal mouse kidney cells. 6-Shogaol reduced the mitochondrial membrane potential (MMP) and released cytochrome c from mitochondria to cytosol via Bax activation. Furthermore, we found that 6-shogaol induced down-regulation of c-FLIP(L) expression at the post-translational levels and the overexpression of c-FLIP(L) markedly inhibited 6-shogaol plus TRAIL-induced apoptosis. Moreover, 6-shogaol increased reactive oxygen species (ROS) production in Caki cells. Pretreatment with ROS scavengers attenuated 6-shogaol plus TRAIL-induced apoptosis through inhibition of MMP reduction and down-regulation of c-FLIP(L) expression. In addition, 6-gingerol, another phenolic alkanone isolated from ginger, did not enhance TRAIL-induced apoptosis and down-regulate c-FLIP(L) expression. Taken together, our results demonstrated that 6-shogaol enhances TRAIL-mediated apoptosis in renal carcinoma Caki cells via ROS-mediated cytochrome c release and down-regulation of c-FLIP(L) expression. PMID:25619640

  8. Analysis of opa1 isoforms expression and apoptosis regulation in autosomal dominant optic atrophy (ADOA) patients with mutations in the opa1 gene.

    Science.gov (United States)

    Formichi, Patrizia; Radi, Elena; Giorgi, Eleonora; Gallus, Gian Nicola; Brunetti, Jlenia; Battisti, Carla; Rufa, Alessandra; Dotti, Maria Teresa; Franceschini, Rossella; Bracci, Luisa; Federico, Antonio

    2015-04-15

    Autosomal dominant optic atrophy (ADOA) is a hereditary optic neuropathy characterized by bilateral symmetrical visual loss, decrease in retinal ganglion cells and a loss of myelin within the optic nerve. ADOA is associated to mutations in Optic atrophy 1 gene (OPA1), which encodes a mitochondrial protein involved in cristae remodeling, maintenance of mitochondrial membrane integrity, mitochondrial fusion and apoptosis regulation. We thus evaluated the rate of apoptosis and the expression levels of OPA1 isoforms in ADOA and control cells. Peripheral blood lymphocytes from eight patients with OPA1 mutation and age matched controls were cultivated both in basal conditions or with 2-deoxy-D-ribose, a reducing sugar that induces apoptosis through oxidative stress. Apoptosis was analyzed by flow cytometry, phosphatidylserine translocation, mitochondrial membrane depolarization and caspase 3 activation. We also analyzed the expression levels of OPA1 isoforms in ADOA and control cells cultured with and without 2-deoxy-D-ribose. We showed an increased percentage of apoptotic cells in ADOA patients compared to controls, both in basal culture conditions and after 2-deoxy-D-ribose treatment. This suggested a great susceptibility of ADOA cells to oxidative stress and a strong correlation between OPA1 protein dysfunctions and morphological-functional alterations to mitochondria. Moreover OPA1 protein expression was significantly decreased in lymphocytes from the ADOA patients after 2-deoxy-D-ribose treatment, implying a great sensitivity of the mutated protein to free radical damage. Concluding, we could confirm that oxidative stress-induced apoptosis may play a key role in the pathophysiological process bringing to retinal ganglion cells degeneration in ADOA. PMID:25796301

  9. Antitumor Activities and Apoptosis-regulated Mechanisms of Fermented Wheat Germ Extract in the Transplantation Tumor Model of Human HT-29 Cells in Nude Mice

    Institute of Scientific and Technical Information of China (English)

    ZHANG Jia Yan; XIAO Xiang; DONG Ying; WU Jing; ZHOU Xing Hua

    2015-01-01

    Objective A subcutaneous transplantation tumor model of human HT-29 cells in nude mice was established to evaluate anticarcinogenic activities, and the apoptosis-regulated mechanism effect of aqueous extract of fermented wheat germ with Lactobacillus plantarum dy-1 (LFWGE). Methods The HT-29 cells were transplanted via subcutaneous injection of 1×107 cells into the right flank of each nude mouse. Then, nude mice were treated for 30 d with LFWGE (high-dose 2 g/kg/d;low-dose 1 g/kg/d) and for 7 d with 5-fluorouracil (5-FU, 25 mg/kg/d) by gavage and intraperitoneal injection, respectively. An inhibition of tumor growth was observed. Results Tumor volume and weights decreased significantly in both groups of nude mice treated with LFWGE. In addition, the cell apoptosis rate of the LFWGE group (2 g/kg/d, 60.1%±4.4%; 1 g/kg/d, 58.6%±6.9%) was significantly higher than that of the control group (11.5%±1.6%) and 5-FU group (32.1%±3.5%) as measured by the TUNEL assay. Moreover, the real-time fluorescent quantitative PCR and Western blot method further confirmed these enhancing apoptosis and growth inhibition effects. The involvement of LFWGE in inducing apoptosis was confirmed by the expression of Bax, Bcl-2, Caspase-3, and CyclinD1. Conclusion The results showed that LFWGE could induce subcutaneous transplantation tumor apoptosis in nude mice and could be as a natural nutrient supplements or chemopreventive agent in the treatment of human colon cancer.

  10. Increased expression of 78 kD glucose-regulated protein promotes cardiomyocyte apoptosis in a rat model of liver cirrhosis

    Science.gov (United States)

    Zhang, Lili; Zhang, Huiying; Lv, Minli; Jia, Jiantao; Fan, Yimin; Tian, Xiaoxia; Li, Xujiong; Li, Baohong; Ji, Jingquan; Wang, Limin; Zhao, Zhongfu; Han, Dewu; Ji, Cheng

    2015-01-01

    Aims: This study was to investigate the role and underlying mechanism of 78 kD glucose-regulated protein (GRP78) in cardiomyocyte apoptosis in a rat model of liver cirrhosis. Methods: A rat model of liver cirrhosis was established with multiple pathogenic factors. A total of 42 male SD rats were randomly divided into the liver cirrhosis group and control group. Cardiac structure analysis was performed to assess alterations in cardiac structure. Cardiomyocytes apoptosis was detected by TdT-mediated dUTP nick end labeling method. Expression of GRP78, CCAAT/enhancer-binding protein homologous protein (CHOP), caspase-12, nuclear factor kappa-light-chain-enhancer of activated B cells p65 subunit (NF-κB p65) and B cell lymphoma-2 (Bcl-2) was detected by immunohistochemical staining. Results: The ratios of left ventricular wall thickness to heart weight and heart weight to body weight were significantly increased with the progression of liver cirrhosis (P < 0.05). Apoptosis index of cardiomyocytes was significantly increased with the progression of liver cirrhosis (P < 0.05). The expression levels of GRP78, CHOP and caspase-12 were significantly increased in the progression of liver cirrhosis (P < 0.05). The expression levels of NF-κB p65 and Bcl-2 were highest in the 4-wk liver cirrhosis, and they were decreased in the 6-wk and 8-wk in the progression of liver cirrhosis. GRP78 expression levels were positively correlated with apoptosis index, CHOP and caspase-12 expression levels (P < 0.05). CHOP expression levels were negatively correlated with NF-κB p65 and Bcl-2 expression levels (P < 0.05). Conclusion: Increased expression of GRP78 promotes cardiomyocyte apoptosis in rats with cirrhotic cardiomyopathy. PMID:26464674

  11. 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

  12. miR-223 contributes to the AGE-promoted apoptosis via down-regulating insulin-like growth factor 1 receptor in osteoblasts.

    Science.gov (United States)

    Qin, Yi; Ye, Jichao; Wang, Peng; Gao, Liangbin; Wang, Suwei; Shen, Huiyong

    2016-01-01

    Advanced glycation end products (AGEs) have been confirmed to induce bone quality deterioration in diabetes mellitus (DM), and to associate with abnormal expression of miRNAs in DM patients or in vitro Recently, miRNAs have been recognized to mediate the onset or progression of DM. In the present study, we investigated the regulation on miR-223 level by AGE-BSA treatment in osteoblast-like MC3T3-E1 cells, with real-time quantitative PCR assay. And then we examined the inhibition of insulin-like growth factor 1 receptor (IGF-1R) expression by miR-223, via targeting of the 3' UTR of IGF-1R with real-time quantitative PCR, western blotting and luciferase reporter assay. Then we explored the regulation of miR-223 and IGF-1R levels, via the lentivirus-mediated miR-223 inhibition and IGF-1R overexpression in the AGE-BSA-induced apoptosis in MC3T3-E1 cells. It was demonstrated that AGE-BSA treatment with more than 100 μg/ml significantly up-regulated miR-223 level, whereas down-regulated IGF-1R level in MC3T3-E1 cells. And the up-regulated miR-223 down-regulated IGF-1R expression in both mRNA and protein levels, via targeting the 3' UTR of IGF-1R Moreover, though the AGE-BSA treatment promoted apoptosis in MC3T3-E1 cells, the IGF-1R overexpression or the miR-223 inhibition significantly attenuated the AGE-BSA-promoted apoptosis in MC3T3-E1 cells. In summary, our study recognized the promotion of miR-223 level by AGE-BSA treatment in osteoblast-like MC3T3-E1 cells. The promoted miR-223 targeted IGF-1R and mediated the AGE-BSA-induced apoptosis in MC3T3-E1 cells. It implies that miR-223 might be an effective therapeutic target to antagonize the AGE-induced damage to osteoblasts in DM.

  13. Anti-inflammatory drugs suppress proliferation and induce apoptosis through altering expressions of cell cycle regulators and pro-apoptotic factors in cultured human osteoblasts

    International Nuclear Information System (INIS)

    It has been reported that anti-inflammatory drugs (AIDs) inhibited bone repair in animal studies, and suppressed proliferation and induced cell death in rat osteoblast cultures. In this study, we further investigated the molecular mechanisms of AID effects on proliferation and cell death in human osteoblasts (hOBs). We examined the effects of dexamethasone (10-7 and 10-6 M), non-selective non-steroidal anti-inflammatory drugs (NSAIDs): indomethacin, ketorolac, piroxicam and diclofenac (10-5 and 10-4 M), and COX-2 inhibitor: celecoxib (10-6 and 10-5 M) on proliferation, cytotoxicity, cell death, and mRNA and protein levels of cell cycle and apoptosis-related regulators in hOBs. All the tested AIDs significantly inhibited proliferation and arrested cell cycle at G0/G1 phase in hOBs. Celecoxib and dexamethasone, but not non-selective NSAIDs, were found to have cytotoxic effects on hOB, and further demonstrated to induce apoptosis and necrosis (at higher concentration) in hOBs. We further found that indomethacin, celecoxib and dexamethasone increased the mRNA and protein expressions of p27kip1 and decreased those of cyclin D2 and p-cdk2 in hOBs. Bak expression was increased by celecoxib and dexamethasone, while Bcl-XL level was declined only by dexamethasone. Furthermore, the replenishment of PGE1, PGE2 or PGF2α did not reverse the effects of AIDs on proliferation and expressions of p27kip1 and cyclin D2 in hOBs. We conclude that the changes in expressions of regulators of cell cycle (p27kip1 and cyclin D2) and/or apoptosis (Bak and Bcl-XL) by AIDs may contribute to AIDs caused proliferation suppression and apoptosis in hOBs. This effect might not relate to the blockage of prostaglandin synthesis by AIDs

  14. Red Light Combined with Blue Light Irradiation Regulates Proliferation and Apoptosis in Skin Keratinocytes in Combination with Low Concentrations of Curcumin.

    Directory of Open Access Journals (Sweden)

    Tianhui Niu

    Full Text Available Curcumin is a widely known natural phytochemical from plant Curcuma longa. In recent years, curcumin has received increasing attention because of its capability to induce apoptosis and inhibit cell proliferation as well as its anti-inflammatory properties in different cancer cells. However, the therapeutic benefits of curcumin are severely hampered due to its particularly low absorption via trans-dermal or oral bioavailability. Phototherapy with visible light is gaining more and more support in dermatological therapy. Red light is part of the visible light spectrum, which is able to deeply penetrate the skin to about 6 mm, and directly affect the fibroblast of the skin dermis. Blue light is UV-free irradiation which is fit for treating chronic inflammation diseases. In this study, we show that curcumin at low concentrations (1.25-3.12 μM has a strong anti-proliferative effect on TNF-α-induced psoriasis-like inflammation when applied in combination with light-emitting-diode devices. The treatment was especially effective when LED blue light at 405 nm was combined with red light at 630 or 660 nm, which markedly amplified the anti-proliferative and apoptosis-inducing effects of curcumin. The experimental results demonstrated that this treatment reduced the viability of human skin keratinocytes, decreased cell proliferation, induced apoptosis, inhibited NF-κB activity and activated caspase-8 and caspase-9 while preserving the cell membrane integrity. Moreover, the combined treatment also down-regulated the phosphorylation level of Akt and ERK. Taken together, our results indicated that the combination of curcumin with LED blue light united red light irradiation can attain a higher efficiency of regulating proliferation and apoptosis in skin keratinocytes.

  15. Nicotine Inhibits Cisplatin-Induced Apoptosis via Regulating α5-nAChR/AKT Signaling in Human Gastric Cancer Cells.

    Directory of Open Access Journals (Sweden)

    Yanfei Jia

    Full Text Available Gastric cancer incidence demonstrates a strong etiologic association with smoking. Nicotine, the major component in tobacco, is a survival agonist that inhibits apoptosis induced by certain chemotherapeutic agents, but the precise mechanisms involved remain largely unknown. Recently studies have indicated that α5-nicotinic acetylcholine receptor (α5-nAChR is highly associated with lung cancer risk and nicotine dependence. Nevertheless, no information has been available about whether nicotine also affects proliferation of human gastric cancer cells through regulation of α5-nAChR. To evaluate the hypothesis that α5-nAChR may play a role in gastric cancer, we investigated its expression in gastric cancer tissues and cell lines. The expression of α5-nAChR increased in gastric cancer tissue compared with para-carcinoma tissues. In view of the results, we proceeded to investigate whether nicotine inhibits cisplatin-induced apoptosis via regulating α5-nAChR in gastric cancer cell. The results showed that nicotine significantly promoted cell proliferation in a dose and time-dependent manner through α5-nAChR activation in human gastric cells. Furthermore, nicotine inhibited apoptosis induced by cisplatin. Silence of α5-nAChR ablated the protective effects of nicotine. However, when co-administrating LY294002, an inhibitor of PI3K/AKT pathway, an increased apoptosis was observed. This effect correlated with the induction of Bcl-2, Bax, Survivin and Caspase-3 by nicotine in gastric cell lines. These results suggest that exposure to nicotine might negatively impact the apoptotic potential of chemotherapeutic drugs and that α5-nAChR/AKT signaling plays a key role in the anti-apoptotic activity of nicotine induced by cisplatin.

  16. Nicotine Inhibits Cisplatin-Induced Apoptosis via Regulating α5-nAChR/AKT Signaling in Human Gastric Cancer Cells.

    Science.gov (United States)

    Jia, Yanfei; Sun, Haiji; Wu, Hongqiao; Zhang, Huilin; Zhang, Xiuping; Xiao, Dongjie; Ma, Xiaoli; Wang, Yunshan

    2016-01-01

    Gastric cancer incidence demonstrates a strong etiologic association with smoking. Nicotine, the major component in tobacco, is a survival agonist that inhibits apoptosis induced by certain chemotherapeutic agents, but the precise mechanisms involved remain largely unknown. Recently studies have indicated that α5-nicotinic acetylcholine receptor (α5-nAChR) is highly associated with lung cancer risk and nicotine dependence. Nevertheless, no information has been available about whether nicotine also affects proliferation of human gastric cancer cells through regulation of α5-nAChR. To evaluate the hypothesis that α5-nAChR may play a role in gastric cancer, we investigated its expression in gastric cancer tissues and cell lines. The expression of α5-nAChR increased in gastric cancer tissue compared with para-carcinoma tissues. In view of the results, we proceeded to investigate whether nicotine inhibits cisplatin-induced apoptosis via regulating α5-nAChR in gastric cancer cell. The results showed that nicotine significantly promoted cell proliferation in a dose and time-dependent manner through α5-nAChR activation in human gastric cells. Furthermore, nicotine inhibited apoptosis induced by cisplatin. Silence of α5-nAChR ablated the protective effects of nicotine. However, when co-administrating LY294002, an inhibitor of PI3K/AKT pathway, an increased apoptosis was observed. This effect correlated with the induction of Bcl-2, Bax, Survivin and Caspase-3 by nicotine in gastric cell lines. These results suggest that exposure to nicotine might negatively impact the apoptotic potential of chemotherapeutic drugs and that α5-nAChR/AKT signaling plays a key role in the anti-apoptotic activity of nicotine induced by cisplatin. PMID:26909550

  17. miR-6734 Up-Regulates p21 Gene Expression and Induces Cell Cycle Arrest and Apoptosis in Colon Cancer Cells

    Science.gov (United States)

    Kang, Moo Rim; Park, Ki Hwan; Yang, Jeong-Ook; Lee, Chang Woo; Oh, Soo Jin; Yun, Jieun; Lee, Myeong Youl; Han, Sang-Bae; Kang, Jong Soon

    2016-01-01

    Recently, microRNAs have been implicated in the regulation of gene expression in terms of both gene silencing and gene activation. Here, we investigated the effects of miR-6734, which has a sequence homology with a specific region of p21WAF1/CIP1 (p21) promoter, on cancer cell growth and the mechanisms involved in this effect. miR-6734 up-regulated p21 expression at both mRNA and protein levels and chromatin immunoprecipitation analysis using biotin-labeled miR-6734 confirmed the association of miR-6734 with p21 promoter. Moreover, miR-6734 inhibited cancer cell growth and induced cell cycle arrest and apoptosis in HCT-116 cells, which was abolished by knockdown of p21. The phosphorylation of Rb and the cleavage of caspase 3 and PARP were suppressed by miR-6734 transfection in HCT-116 cells and these effects were also reversed by p21 knockdown. In addition, miR-6734 transfection caused prolonged induction of p21 gene and modification of histones in p21 promoter, which are typical aspects of a phenomenon referred to as RNA activation (RNAa). Collectively, our results demonstrated that miR-6734 inhibits the growth of colon cancer cells by up-regulating p21 gene expression and subsequent induction of cell cycle arrest and apoptosis, suggesting its role as an important endogenous regulator of cancer cell proliferation and survival. PMID:27509128

  18. HERG K+ channels expression in gastric cancers and analysis of its regulation in tumor cell proliferation and apoptosis

    Institute of Scientific and Technical Information of China (English)

    Qing Lü; Huiyu Li; Xiaoming Lu; Guobin Wang

    2009-01-01

    Objective: To investigate the expression of herg 1 gene in tumor tissues from gastric carcinomas and gastric carcinoma cell lines, and study the relationship between HERG K+ channel expressions and tumor cell proliferation and apoptosis. Methods: RT-PCR and PCR assays were used to detect the expression of herg 1 gene in 64 gastric carcinomas and the gastric cancer cell line SGC-7901. Blocking the HERG K+ channels was used to evaluate their effects on tumor cell proliferation and apoptosis. Results:The statistically significant expression of herg 1 gene was detected in all the gastric cancers and SGC-7901 cells, but not in normal tissues. The HERG K+ channel blocker, E-4031, increased the cell population in G0/G1 (P<0.05) and the number of apoptotic tumor cells(P<0.05). Conclusion: HERG K+ channels were expressed in all gastric carcinomas tested and these channels appear to modulate tumor cell proliferation and apoptosis.

  19. Down-regulation of Survivin by Antisense Oligonucleotides Increases Apoptosis, Inhibits Cytokinesis and Anchorage-Independent Growth

    Directory of Open Access Journals (Sweden)

    Jun Chen

    2000-05-01

    Full Text Available Survivin, a member of the inhibitor of apoptosis protein (IAP family, is detected in most common human cancers but not in adjacent normal cells. Previous studies suggest that survivin associates with the mitotic spindle and directly inhibits caspase activity. To further investigate the function of survivin, we used a survivin antisense (AS oligonucleotide to downregulate survivin expression in normal and cancer cells. We found that inhibition of survivin expression increased apoptosis and polyploidy while decreasing colony formation in soft agar. Immunohistochemistry showed that cells without survivin can initiate the cleavage furrow and contractile ring, but cannot complete cytokinesis, thus resulting in multinucleated cells. These findings indicate that survivin plays important roles in a late stage of cytokinesis, as well as in apoptosis.

  20. Down-regulation of cellular FLICE-inhibitory protein (Long Form contributes to apoptosis induced by Hsp90 inhibition in human lung cancer cells

    Directory of Open Access Journals (Sweden)

    Wang Qilin

    2012-12-01

    Full Text Available Abstract Background Cellular FLICE-Inhibitory Protein (long form, c-FLIPL is a critical negative regulator of death receptor-mediated apoptosis. Overexpression of c-FLIPL has been reported in many cancer cell lines and is associated with chemoresistance. In contrast, down-regulation of c-FLIP may drive cancer cells into cellular apoptosis. This study aims to demonstrate that inhibition of the heat shock protein 90 (Hsp90 either by inhibitors geldanamycin/17-N-Allylamino-17-demethoxygeldanamycin (GA/17-AAG or siRNA technique in human lung cancer cells induces c-FLIPL degradation and cellular apoptosis through C-terminus of Hsp70-interacting protein (CHIP-mediated mechanisms. Methods Calu-1 and H157 cell lines (including H157-c-FLIPL overexpressing c-FLIPL and control cell H157-lacZ were treated with 17-AAG and the cell lysates were prepared to detect the given proteins by Western Blot and the cell survival was assayed by SRB assay. CHIP and Hsp90 α/β proteins were knocked down by siRNA technique. CHIP and c-FLIPL plasmids were transfected into cells and immunoprecipitation experiments were performed to testify the interactions between c-FLIPL, CHIP and Hsp90. Results c-FLIPL down-regulation induced by 17-AAG can be reversed with the proteasome inhibitor MG132, which suggested that c-FLIPL degradation is mediated by a ubiquitin-proteasome system. Inhibition of Hsp90α/β reduced c-FLIPL level, whereas knocking down CHIP expression with siRNA technique inhibited c-FLIPL degradation. Furthermore, c-FLIPL and CHIP were co-precipitated in the IP complexes. In addition, overexpression of c-FLIPL can rescue cancer cells from apoptosis. When 17-AAG was combined with an anti-cancer agent celecoxib(CCB, c-FLIPL level declined further and there was a higher degree of caspase activation. Conclusion We have elucidated c-FLIPL degradation contributes to apoptosis induced by Hsp90 inhibition, suggesting c-FLIP and Hsp90 may be the promising combined targets

  1. Midazolam regulated caspase pathway, endoplasmic reticulum stress, autophagy, and cell cycle to induce apoptosis in MA-10 mouse Leydig tumor cells

    Directory of Open Access Journals (Sweden)

    So EC

    2016-04-01

    Full Text Available Edmund Cheung So,1,2 Yung-Chia Chen,3 Shu-Chun Wang,4 Chia-Ching Wu,4 Man-Chi Huang,4 Meng-Shao Lai,4 Bo-Syong Pan,4,5 Fu-Chi Kang,6 Bu-Miin Huang4 1Department of Anesthesia, An Nan Hospital, China Medical University, Tainan, Taiwan, Republic of China; 2Department of Anesthesia, School of Medicine, China Medical University, Taichung, Taiwan; Republic of China; 3Department of Anatomy, School of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan, Republic of China; 4Department of Cell Biology and Anatomy, College of Medicine, National Cheng Kung University, Tainan, Taiwan, Republic of China; 5Department of Cancer Biology, Wake Forest University School of Medicine, Winston Salem, NC, USA; 6Department of Anesthesia, Chi Mei Medical Center, Chiali, Tainan, Taiwan, Republic of China Purpose: Midazolam is widely used as a sedative and anesthetic induction agent by modulating the different GABA receptors in the central nervous system. Studies have also shown that midazolam has an anticancer effect on various tumors. In a previous study, we found that midazolam could induce MA-10 mouse Leydig tumor cell apoptosis by activating caspase cascade. However, the detailed mechanism related to the upstream and downstream pathways of the caspase cascade, such as endoplasmic reticulum (ER stress, autophagy, and p53 pathways plus cell cycle regulation in MA-10 mouse Leydig tumor cells, remains elusive.Methods: Flow cytometry assay and Western blot analyses were exploited.Results: Midazolam significantly decreased cell viability but increased sub-G1 phase cell numbers in MA-10 cells (P<0.05. Annexin V/propidium iodide double staining further confirmed that midazolam induced apoptosis. In addition, expressions of Fas and Fas ligand could be detected in MA-10 cells with midazolam treatments, and Bax translocation and cytochrome c release were also involved in midazolam-induced MA-10 cell apoptosis. Moreover, the staining and expression of LC3-II proteins could

  2. Plumbagin Enhances TRAIL-mediated Apoptosis through Up-regulation of Death Receptor in Human Melanoma A375 Cells

    Institute of Scientific and Technical Information of China (English)

    李家文; 沈琴; 彭锐; 陈嵘袆; 蒋苹; 李艳秋; 张丽; 卢静静

    2010-01-01

    Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a promising anti-cancer agent. However, emergence of drug resistance limits its potential use. Plumbagin is a natural quinonoid compound isolated from plant. In this study, induced apoptosis effect of the combined treatment with plumbagin and TRAIL on human melanoma A375 cell line was examined and possible mechanism was investigated. The cells were divided into four groups: control group, plumbagin group (plumbagin, 5 or 10 μmol/L), TRAIL gr...

  3. Down-regulation of estrogen receptor-alpha and rearranged during transfection tyrosine kinase is associated with withaferin a-induced apoptosis in MCF-7 breast cancer cells

    Directory of Open Access Journals (Sweden)

    Samadi Abbas K

    2011-10-01

    Full Text Available Abstract Background Withaferin A (WA, a naturally occurring withanolide, induces apoptosis in both estrogen-responsive MCF-7 and estrogen-independent MDA-MB-231 breast cancer cell lines with higher sensitivity in MCF-7 cells, but the underlying mechanisms are not well defined. The purpose of this study was to determine the anti-cancer effects of WA in MCF-7 breast cancer cells and explore alterations in estrogen receptor alpha (ERα and its associated molecules in vitro as novel mechanisms of WA action. Methods The effects of WA on MCF-7 viability and proliferation were evaluated by 3-(4, 5-dimethylthiazol-2-yl-5-(3-carboxymethoxyphenyl-2-(4-sulfophenyl-2H-tetrazolium (MTS assay and trypan blue exclusion assays. Apoptosis was evaluated by Annexin V-fluorescein isothiocyanate (FITC/propidium iodide (PI flow cytometry and Western blot analysis of poly (ADP-ribose polymerase (PARP cleavage. Cell cycle effects were analyzed by PI flow cytometry. Western blotting was also conducted to examine alterations in the expression of ERα and pathways that are associated with ERα function. Results WA resulted in growth inhibition and decreased viability in MCF-7 cells with an IC50 of 576 nM for 72 h. It also caused a dose- and time-dependent apoptosis and G2/M cell cycle arrest. WA-induced apoptosis was associated with down-regulation of ERα, REarranged during Transfection (RET tyrosine kinase, and heat shock factor-1 (HSF1, as well as up-regulation of phosphorylated p38 mitogen-activated protein kinase (phospho-p38 MAPK, p53 and p21 protein expression. Co-treatment with protein synthesis inhibitor cycloheximide or proteasome inhibitor MG132 revealed that depletion of ERα by WA is post-translational, due to proteasome-dependent ERα degradation. Conclusions Taken together, down-regulation of ERα, RET, HSF1 and up-regulation of phospho-p38 MAPK, p53, p21 are involved in the pro-apoptotic and growth-inhibitory effects of WA in MCF-7 breast cancer cells in

  4. Vincristine induced apoptosis in acute lymphoblastic leukaemia cells: A mitochondrial controlled pathway regulated by reactive oxygen species?

    NARCIS (Netherlands)

    Groninger, E.; Boer, A.W. de; Graaf, S.S.N. de; Kamps, W.A.; Bont, E.S. de

    2002-01-01

    Vincristine (VCR), a microtubule interfering anti-cancer agent, plays a key role in the treatment of childhood acute lymphoblastic leukaemia (ALL). The route of VCR induced apoptosis in ALL cells is not well defined. In this study we demonstrated caspase-9 and -3 activation in vivo in bone marrow le

  5. FoxO3a transcriptional regulation of bim controls apoptosis in paclitaxel-treated breast cancer cell lines

    NARCIS (Netherlands)

    Sunters, A; de Mattos, SF; Stahl, M; Brosens, JJ; Zoumpoulidou, G; Saunders, CA; Coffer, PJ; Medema, RH; Coombes, RC; Lam, EWF

    2003-01-01

    Paclitaxel is used to treat breast cancers, but the mechanisms by which it induces apoptosis are poorly understood. Consequently, we have studied the role of the FoxO transcription factors in determining cellular response to paclitaxel. Western blotting revealed that in a panel of nine breast cancer

  6. Regulation of Mitochondria-dependent Apoptosis in Non-Small Cell Lung Cancer: Implications for Cancer Therapy

    NARCIS (Netherlands)

    Checinska, A.

    2007-01-01

    Summary The work described in this thesis focuses on the characterization of the mechanism(s) underlying the deregulated activation of the intrinsic or mitochondrial apoptotic pathway in non-small cell lung cancer (NSCLC) cells. Apoptosis suppression might contribute to the chemoresistance often o

  7. FoxO3a transcriptional regulation of Bim controls apoptosis in paclitaxel-treated breast cancer cell lines

    NARCIS (Netherlands)

    Sunters, A.; Fernandez de Mattos, S.; Stahl, M.; Brosens, J.J.; Zoumpoulidou, G.; Saunders, C.A.; Coffer, P.J.; Medema, R.H.; Coombes, R.C.; Lam, E.W.-F.

    2003-01-01

    Paclitaxel is used to treat breast cancers, but the mechanisms by which it induces apoptosis are poorly understood. Consequently, we have studied the role of the FoxO transcription factors in determining cellular response to paclitaxel. Western blotting revealed that in a panel of nine breast cancer

  8. The long non-coding RNA HOTAIR promotes the proliferation of serous ovarian cancer cells through the regulation of cell cycle arrest and apoptosis

    Energy Technology Data Exchange (ETDEWEB)

    Qiu, Jun-jun [Department of Gynecology, Obstetrics and Gynecology Hospital, Fudan University, 419 Fangxie Road, Shanghai 200011 (China); Department of Obstetrics and Gynecology of Shanghai Medical College, Fudan University, 138 Yixueyuan Road, Shanghai 200032 (China); Shanghai Key Laboratory of Female Reproductive Endocrine-Related Diseases, 413 Zhaozhou Road, Shanghai 200011 (China); Wang, Yan [Cancer Institute, Fudan University Shanghai Cancer Center, 270 Dong' an Road, Shanghai 200032 (China); Department of Oncology, Shanghai Medical College, Fudan University, 130 Dong' an Road, Shanghai 200032 (China); Ding, Jing-xin; Jin, Hong-yan [Department of Gynecology, Obstetrics and Gynecology Hospital, Fudan University, 419 Fangxie Road, Shanghai 200011 (China); Department of Obstetrics and Gynecology of Shanghai Medical College, Fudan University, 138 Yixueyuan Road, Shanghai 200032 (China); Shanghai Key Laboratory of Female Reproductive Endocrine-Related Diseases, 413 Zhaozhou Road, Shanghai 200011 (China); Yang, Gong, E-mail: yanggong@fudan.edu.cn [Cancer Institute, Fudan University Shanghai Cancer Center, 270 Dong' an Road, Shanghai 200032 (China); Department of Oncology, Shanghai Medical College, Fudan University, 130 Dong' an Road, Shanghai 200032 (China); Hua, Ke-qin, E-mail: huakeqin@126.com [Department of Gynecology, Obstetrics and Gynecology Hospital, Fudan University, 419 Fangxie Road, Shanghai 200011 (China); Department of Obstetrics and Gynecology of Shanghai Medical College, Fudan University, 138 Yixueyuan Road, Shanghai 200032 (China); Shanghai Key Laboratory of Female Reproductive Endocrine-Related Diseases, 413 Zhaozhou Road, Shanghai 200011 (China)

    2015-05-01

    HOX transcript antisense RNA (HOTAIR) is a well-known long non-coding RNA (lncRNA) whose dysregulation correlates with poor prognosis and malignant progression in many forms of cancer. Here, we investigate the expression pattern, clinical significance, and biological function of HOTAIR in serous ovarian cancer (SOC). Clinically, we found that HOTAIR levels were overexpressed in SOC tissues compared with normal controls and that HOTAIR overexpression was correlated with an advanced FIGO stage and a high histological grade. Multivariate analysis revealed that HOTAIR is an independent prognostic factor for predicting overall survival in SOC patients. We demonstrated that HOTAIR silencing inhibited A2780 and OVCA429 SOC cell proliferation in vitro and that the anti-proliferative effects of HOTAIR silencing also occurred in vivo. Further investigation into the mechanisms responsible for the growth inhibitory effects by HOTAIR silencing revealed that its knockdown resulted in the induction of cell cycle arrest and apoptosis through certain cell cycle-related and apoptosis-related proteins. Together, these results highlight a critical role of HOTAIR in SOC cell proliferation and contribute to a better understanding of the importance of dysregulated lncRNAs in SOC progression. - Highlights: • HOTAIR overexpression correlates with an aggressive tumour phenotype and a poor prognosis in SOC. • HOTAIR promotes SOC cell proliferation both in vitro and in vivo. • The proliferative role of HOTAIR is associated with regulation of the cell cycle and apoptosis.

  9. Protection by sulforaphane from type 1 diabetes-induced testicular apoptosis is associated with the up-regulation of Nrf2 expression and function

    International Nuclear Information System (INIS)

    Diabetes-induced testicular apoptosis is predominantly due to increased oxidative stress. The nuclear factor-erythroid 2-related factor 2 (Nrf2), as a master transcription factor in controlling anti-oxidative systems, is able to be induced by sulforaphane (SFN). To examine whether SFN prevents testicular apoptosis, type 1 diabetic mouse model was induced with multiple low-dose streptozotocin. Diabetic and age-matched control mice were treated with and without SFN at 0.5 mg/kg daily in five days of each week for 3 months and then kept until 6 months. Diabetes significantly increased testicular apoptosis that was associated with endoplasmic reticulum stress and mitochondrial cell death pathways, shown by the increased expression of C/EBP homologous protein (CHOP), cleaved caspase-12, Bax to Bcl2 expression ratio, and cleaved caspase-3. Diabetes also significantly increased testicular oxidative damage, inflammation and fibrosis, and decreased germ cell proliferation. All these diabetic effects were significantly prevented by SFN treatment for the first 3 months, and the protective effect could be sustained at 3 months after SFN treatment. SFN was able to up-regulate Nrf2 expression and function. The latter was reflected by the increased phosphorylation of Nrf2 at Ser40 and expression of Nrf2 downstream antioxidants at mRNA and protein levels. These results suggest that type 1 diabetes significantly induced testicular apoptosis and damage along with increasing oxidative stress and cell death and suppressing Nrf2 expression and function. SFN is able to prevent testicular oxidative damage and apoptosis in type 1 diabetes mice, which may be associated with the preservation of testicular Nrf2 expression and function under diabetic condition. - Highlights: • Sulforaphane (SFN) could attenuate diabetes-induced germ cell apoptosis. • SFN could preserve germ cell proliferation under diabetic conditions. • SFN testicular protection was sustained until 3 months after

  10. Protection by sulforaphane from type 1 diabetes-induced testicular apoptosis is associated with the up-regulation of Nrf2 expression and function

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Xin; Bai, Yang; Zhang, Zhiguo [The First Hospital of Jilin University, Changchun 130021 (China); KCHRI at the Department of Pediatrics, The University of Louisville, Louisville 40202 (United States); Xin, Ying, E-mail: xiny@jlu.edu.cn [KCHRI at the Department of Pediatrics, The University of Louisville, Louisville 40202 (United States); Key Laboratory of Pathobiology, Ministry of Education, Jilin University, Changchun 130021 (China); Cai, Lu, E-mail: l0cai001@louisville.edu [The First Hospital of Jilin University, Changchun 130021 (China); KCHRI at the Department of Pediatrics, The University of Louisville, Louisville 40202 (United States)

    2014-09-01

    Diabetes-induced testicular apoptosis is predominantly due to increased oxidative stress. The nuclear factor-erythroid 2-related factor 2 (Nrf2), as a master transcription factor in controlling anti-oxidative systems, is able to be induced by sulforaphane (SFN). To examine whether SFN prevents testicular apoptosis, type 1 diabetic mouse model was induced with multiple low-dose streptozotocin. Diabetic and age-matched control mice were treated with and without SFN at 0.5 mg/kg daily in five days of each week for 3 months and then kept until 6 months. Diabetes significantly increased testicular apoptosis that was associated with endoplasmic reticulum stress and mitochondrial cell death pathways, shown by the increased expression of C/EBP homologous protein (CHOP), cleaved caspase-12, Bax to Bcl2 expression ratio, and cleaved caspase-3. Diabetes also significantly increased testicular oxidative damage, inflammation and fibrosis, and decreased germ cell proliferation. All these diabetic effects were significantly prevented by SFN treatment for the first 3 months, and the protective effect could be sustained at 3 months after SFN treatment. SFN was able to up-regulate Nrf2 expression and function. The latter was reflected by the increased phosphorylation of Nrf2 at Ser40 and expression of Nrf2 downstream antioxidants at mRNA and protein levels. These results suggest that type 1 diabetes significantly induced testicular apoptosis and damage along with increasing oxidative stress and cell death and suppressing Nrf2 expression and function. SFN is able to prevent testicular oxidative damage and apoptosis in type 1 diabetes mice, which may be associated with the preservation of testicular Nrf2 expression and function under diabetic condition. - Highlights: • Sulforaphane (SFN) could attenuate diabetes-induced germ cell apoptosis. • SFN could preserve germ cell proliferation under diabetic conditions. • SFN testicular protection was sustained until 3 months after

  11. Epithelial-specific ETS-1 (ESE1/ELF3) regulates apoptosis of intestinal epithelial cells in ulcerative colitis via accelerating NF-κB activation.

    Science.gov (United States)

    Li, Liren; Miao, Xianjing; Ni, Runzhou; Miao, Xiaobing; Wang, Liang; Gu, Xiaodan; Yan, Lijun; Tang, Qiyun; Zhang, Dongmei

    2015-06-01

    Epithelial-specific ETS-1 (ESE1), also named as ELF3, ERT and ESX, belonging to the ETS family of transcription factors, exerts multiple activities in inflammation, epithelial differentiation and cancer development. Previous data demonstrated that ESE1 synergizes with NF-κB to induce inflammation and drive tumor progress, and the nuclear translocation of ESE1 promotes colon cells apoptosis. However, the expression and biological functions of ESE1 in ulcerative colitis (UC) remain unclear. In this study, we reported for the first time that ESE1/ELF3 was over-expressed in intestinal epithelial cells (IECs) of patients with UC. In DSS-induced colitis mouse models, we observed the up-regulation of ESE1/ELF3 accompanied with the elevated levels of IEC apoptotic markers (active caspase-3 and cleaved PARP) and NF-κB activation indicators [phosphorylated NF-κB p65 subunit (p-p65) and p-IκB] in colitis IECs. Increased co-localization of ESE1/ELF3 with active caspase-3 (and p-p65) in IECs of the DSS-induced colitis group further indicated the possible involvement of ESE1/ELF3 in NF-κB-mediated IEC apoptosis in UC. Employing the TNF-α-treated HT-29 cells as an IEC apoptosis model, we confirmed the positive correlation of ESE1/ELF3 with NF-κB activation and caspase-dependent IEC apoptosis in vitro. Immunoprecipitation and immunofluorescence assay revealed the physical interaction and increased nuclear translocation of ESE1/ELF3 and the NF-κB p65 subunit in TNF-α-treated HT-29 cells. Knocking ESE1/ELF3 down by siRNA significantly alleviated TNF-α-induced NF-κB activation and cellular apoptosis in HT-29 cells. Taken together, our data suggested that ESE1/ELF3 may promote the UC progression via accelerating NF-κB activation and thus facilitating IEC apoptosis.

  12. Cellular inhibitor of apoptosis protein-1 (cIAP1) can regulate E2F1 transcription factor-mediated control of cyclin transcription.

    Science.gov (United States)

    Cartier, Jessy; Berthelet, Jean; Marivin, Arthur; Gemble, Simon; Edmond, Valérie; Plenchette, Stéphanie; Lagrange, Brice; Hammann, Arlette; Dupoux, Alban; Delva, Laurent; Eymin, Béatrice; Solary, Eric; Dubrez, Laurence

    2011-07-29

    The inhibitor of apoptosis protein cIAP1 (cellular inhibitor of apoptosis protein-1) is a potent regulator of the tumor necrosis factor (TNF) receptor family and NF-κB signaling pathways in the cytoplasm. However, in some primary cells and tumor cell lines, cIAP1 is expressed in the nucleus, and its nuclear function remains poorly understood. Here, we show that the N-terminal part of cIAP1 directly interacts with the DNA binding domain of the E2F1 transcription factor. cIAP1 dramatically increases the transcriptional activity of E2F1 on synthetic and CCNE promoters. This function is not conserved for cIAP2 and XIAP, which are cytoplasmic proteins. Chromatin immunoprecipitation experiments demonstrate that cIAP1 is recruited on E2F binding sites of the CCNE and CCNA promoters in a cell cycle- and differentiation-dependent manner. cIAP1 silencing inhibits E2F1 DNA binding and E2F1-mediated transcriptional activation of the CCNE gene. In cells that express a nuclear cIAP1 such as HeLa, THP1 cells and primary human mammary epithelial cells, down-regulation of cIAP1 inhibits cyclin E and A expression and cell proliferation. We conclude that one of the functions of cIAP1 when localized in the nucleus is to regulate E2F1 transcriptional activity. PMID:21653699

  13. Cellular inhibitor of apoptosis protein-1 (cIAP1) can regulate E2F1 transcription factor-mediated control of cyclin transcription.

    Science.gov (United States)

    Cartier, Jessy; Berthelet, Jean; Marivin, Arthur; Gemble, Simon; Edmond, Valérie; Plenchette, Stéphanie; Lagrange, Brice; Hammann, Arlette; Dupoux, Alban; Delva, Laurent; Eymin, Béatrice; Solary, Eric; Dubrez, Laurence

    2011-07-29

    The inhibitor of apoptosis protein cIAP1 (cellular inhibitor of apoptosis protein-1) is a potent regulator of the tumor necrosis factor (TNF) receptor family and NF-κB signaling pathways in the cytoplasm. However, in some primary cells and tumor cell lines, cIAP1 is expressed in the nucleus, and its nuclear function remains poorly understood. Here, we show that the N-terminal part of cIAP1 directly interacts with the DNA binding domain of the E2F1 transcription factor. cIAP1 dramatically increases the transcriptional activity of E2F1 on synthetic and CCNE promoters. This function is not conserved for cIAP2 and XIAP, which are cytoplasmic proteins. Chromatin immunoprecipitation experiments demonstrate that cIAP1 is recruited on E2F binding sites of the CCNE and CCNA promoters in a cell cycle- and differentiation-dependent manner. cIAP1 silencing inhibits E2F1 DNA binding and E2F1-mediated transcriptional activation of the CCNE gene. In cells that express a nuclear cIAP1 such as HeLa, THP1 cells and primary human mammary epithelial cells, down-regulation of cIAP1 inhibits cyclin E and A expression and cell proliferation. We conclude that one of the functions of cIAP1 when localized in the nucleus is to regulate E2F1 transcriptional activity.

  14. Inhibition of SH2-domain-containing inositol 5-phosphatase (SHIP2) ameliorates palmitate induced-apoptosis through regulating Akt/FOXO1 pathway and ROS production in HepG2 cells

    Energy Technology Data Exchange (ETDEWEB)

    Gorgani-Firuzjaee, Sattar [Department of Biochemistry, Faculty of Medicine, Tehran University of Medical Sciences, Tehran, Islamic Republic of Iran (Iran, Islamic Republic of); Adeli, Khosrow [Division of Clinical Biochemistry, The Hospital for Sick Children, University of Toronto, Toronto (Canada); Meshkani, Reza, E-mail: rmeshkani@tums.ac.ir [Department of Biochemistry, Faculty of Medicine, Tehran University of Medical Sciences, Tehran, Islamic Republic of Iran (Iran, Islamic Republic of)

    2015-08-21

    The serine–threonine kinase Akt regulates proliferation and survival by phosphorylating a network of protein substrates; however, the role of a negative regulator of the Akt pathway, the SH2-domain-containing inositol 5-phosphatase (SHIP2) in apoptosis of the hepatocytes, remains unknown. In the present study, we studied the molecular mechanisms linking SHIP2 expression to apoptosis using overexpression or suppression of SHIP2 gene in HepG2 cells exposed to palmitate (0.5 mM). Overexpression of the dominant negative mutant SHIP2 (SHIP2-DN) significantly reduced palmitate-induced apoptosis in HepG2 cells, as these cells had increased cell viability, decreased apoptotic cell death and reduced the activity of caspase-3, cytochrome c and poly (ADP-ribose) polymerase. Overexpression of the wild-type SHIP2 gene led to a massive apoptosis in HepG2 cells. The protection from palmitate-induced apoptosis by SHIP2 inhibition was accompanied by a decrease in the generation of reactive oxygen species (ROS). In addition, SHIP2 inhibition was accompanied by an increased Akt and FOXO-1 phosphorylation, whereas overexpression of the wild-type SHIP2 gene had the opposite effects. Taken together, these findings suggest that SHIP2 expression level is an important determinant of hepatic lipoapotosis and its inhibition can potentially be a target in treatment of hepatic lipoapoptosis in diabetic patients. - Highlights: • Lipoapoptosis is the major contributor to the development of NAFLD. • The PI3-K/Akt pathway regulates apoptosis in different cells. • The role of negative regulator of this pathway, SHIP2 in lipoapoptosis is unknown. • SHIP2 inhibition significantly reduces palmitate-induced apoptosis in HepG2 cells. • SHIP2 inhibition prevents palmitate induced-apoptosis by regulating Akt/FOXO1 pathway.

  15. Fas-mediated apoptosis regulates the composition of peripheral alphabeta T cell repertoire by constitutively purging out double negative T cells.

    Directory of Open Access Journals (Sweden)

    Abdiaziz S Mohamood

    Full Text Available BACKGROUND: The Fas pathway is a major regulator of T cell homeostasis, however, the T cell population that is controlled by the Fas pathway in vivo is poorly defined. Although CD4 and CD8 single positive (SP T cells are the two major T cell subsets in the periphery of wild type mice, the repertoire of mice bearing loss-of-function mutation in either Fas (lpr mice or Fas ligand (gld mice is predominated by CD4(-CD8(- double negative alphabeta T cells that also express B220 and generally referred to as B220+DN T cells. Despite extensive analysis, the basis of B220+DN T cell lymphoproliferation remains poorly understood. In this study we re-examined the issue of why T cell lymphoproliferation caused by gld mutation is predominated by B220+DN T cells. METHODOLOGY AND PRINCIPAL FINDINGS: We combined the following approaches to study this question: Gene transcript profiling, BrdU labeling, and apoptosis assays. Our results show that B220+DN T cells are proliferating and dying at exceptionally high rates than SP T cells in the steady state. The high proliferation rate is restricted to B220+DN T cells found in the gut epithelium whereas the high apoptosis rate occurred both in the gut epithelium and periphery. However, only in the periphery, apoptosis of B220+DN T cell is Fas-dependent. When the Fas pathway is genetically impaired, apoptosis of peripheral B220+DN T cells was reduced to a baseline level similar to that of SP T cells. Under these conditions of normalized apoptosis, B220+DN T cells progressively accumulate in the periphery, eventually resulting in B220+DN T cell lymphoproliferation. CONCLUSIONS/SIGNIFICANCE: The Fas pathway plays a critical role in regulating the tissue distribution of DN T cells through targeting and elimination of DN T cells from the periphery in the steady state. The results provide new insight into pathogenesis of DN T cell lymphoproliferation.

  16. Expression, regulation and function of phosphofructo-kinase/fructose-biphosphatases (PFKFBs in glucocorticoid-induced apoptosis of acute lymphoblastic leukemia cells

    Directory of Open Access Journals (Sweden)

    Schmidt Stefan

    2010-11-01

    Full Text Available Abstract Background Glucocorticoids (GCs cause apoptosis and cell cycle arrest in lymphoid cells and constitute a central component in the therapy of lymphoid malignancies, most notably childhood acute lymphoblastic leukemia (ALL. PFKFB2 (6-phosphofructo-2-kinase/fructose-2,6-biphosphatase-2, a kinase controlling glucose metabolism, was identified by us previously as a GC response gene in expression profiling analyses performed in children with ALL during initial systemic GC mono-therapy. Since deregulation of glucose metabolism has been implicated in apoptosis induction, this gene and its relatives, PFKFB1, 3, and 4, were further analyzed. Methods Gene expression analyses of isolated lymphoblasts were performed on Affymetrix HGU133 Plus 2.0 microarrays. GCRMA normalized microarray data were analyzed using R-Bioconductor packages version 2.5. Functional gene analyses of PFKFB2-15A and -15B isoforms were performed by conditional gene over-expression experiments in the GC-sensitive T-ALL model CCRF-CEM. Results Expression analyses in additional ALL children, non-leukemic individuals and leukemic cell lines confirmed frequent PFKFB2 induction by GC in most systems sensitive to GC-induced apoptosis, particularly T-ALL cells. The 3 other family members, in contrast, were either absent or only weakly expressed (PFKFB1 and 4 or not induced by GC (PFKFB3. Conditional PFKFB2 over-expression in the CCRF-CEM T-ALL in vitro model revealed that its 2 splice variants (PFKFB2-15A and PFKFB2-15B had no detectable effect on cell survival. Moreover, neither PFKFB2 splice variant significantly affected sensitivity to, or kinetics of, GC-induced apoptosis. Conclusions Our data suggest that, at least in the model system investigated, PFKFB2 is not an essential upstream regulator of the anti-leukemic effects of GC.

  17. Expression, regulation and function of phosphofructo-kinase/fructose-biphosphatases (PFKFBs) in glucocorticoid-induced apoptosis of acute lymphoblastic leukemia cells

    International Nuclear Information System (INIS)

    Glucocorticoids (GCs) cause apoptosis and cell cycle arrest in lymphoid cells and constitute a central component in the therapy of lymphoid malignancies, most notably childhood acute lymphoblastic leukemia (ALL). PFKFB2 (6-phosphofructo-2-kinase/fructose-2,6-biphosphatase-2), a kinase controlling glucose metabolism, was identified by us previously as a GC response gene in expression profiling analyses performed in children with ALL during initial systemic GC mono-therapy. Since deregulation of glucose metabolism has been implicated in apoptosis induction, this gene and its relatives, PFKFB1, 3, and 4, were further analyzed. Gene expression analyses of isolated lymphoblasts were performed on Affymetrix HGU133 Plus 2.0 microarrays. GCRMA normalized microarray data were analyzed using R-Bioconductor packages version 2.5. Functional gene analyses of PFKFB2-15A and -15B isoforms were performed by conditional gene over-expression experiments in the GC-sensitive T-ALL model CCRF-CEM. Expression analyses in additional ALL children, non-leukemic individuals and leukemic cell lines confirmed frequent PFKFB2 induction by GC in most systems sensitive to GC-induced apoptosis, particularly T-ALL cells. The 3 other family members, in contrast, were either absent or only weakly expressed (PFKFB1 and 4) or not induced by GC (PFKFB3). Conditional PFKFB2 over-expression in the CCRF-CEM T-ALL in vitro model revealed that its 2 splice variants (PFKFB2-15A and PFKFB2-15B) had no detectable effect on cell survival. Moreover, neither PFKFB2 splice variant significantly affected sensitivity to, or kinetics of, GC-induced apoptosis. Our data suggest that, at least in the model system investigated, PFKFB2 is not an essential upstream regulator of the anti-leukemic effects of GC

  18. Toll-like receptor 3 regulates angiogenesis and apoptosis in prostate cancer cell lines through hypoxia-inducible factor 1 alpha.

    Science.gov (United States)

    Paone, Alessio; Galli, Roberta; Gabellini, Chiara; Lukashev, Dmitriy; Starace, Donatella; Gorlach, Agnes; De Cesaris, Paola; Ziparo, Elio; Del Bufalo, Donatella; Sitkovsky, Michail V; Filippini, Antonio; Riccioli, Anna

    2010-07-01

    Toll-like receptors (TLRs) recognize microbial/viral-derived components that trigger innate immune response and conflicting data implicate TLR agonists in cancer, either as protumor or antitumor agents. We previously demonstrated that TLR3 activation mediated by its agonist poly(I:C) induces antitumor signaling, leading to apoptosis of prostate cancer cells LNCaP and PC3 with much more efficiency in the former than in the second more aggressive line. The transcription factor hypoxia-inducible factor 1 (HIF-1) regulates several cellular processes, including apoptosis, in response to hypoxia and to other stimuli also in normoxic conditions. Here we describe a novel protumor machinery triggered by TLR3 activation in PC3 cells consisting of increased expression of the specific I.3 isoform of HIF-1 alpha and nuclear accumulation of HIF-1 complex in normoxia, resulting in reduced apoptosis and in secretion of functional vascular endothelial growth factor (VEGF). Moreover, we report that, in the less aggressive LNCaP cells, TLR3 activation fails to induce nuclear accumulation of HIF-1 alpha. However, the transfection of I.3 isoform of hif-1 alpha in LNCaP cells allows poly(I:C)-induced HIF-1 activation, resulting in apoptosis protection and VEGF secretion. Altogether, our findings demonstrate that differences in the basal level of HIF-1 alpha expression in different prostate cancer cell lines underlie their differential response to TLR3 activation, suggesting a correlation between different stages of malignancy, hypoxic gene expression, and beneficial responsiveness to TLR agonists. PMID:20651983

  19. Toll-like Receptor 3 Regulates Angiogenesis and Apoptosis in Prostate Cancer Cell Lines through Hypoxia-Inducible Factor 1α1

    Science.gov (United States)

    Paone, Alessio; Galli, Roberta; Gabellini, Chiara; Lukashev, Dmitriy; Starace, Donatella; Gorlach, Agnes; De Cesaris, Paola; Ziparo, Elio; Del Bufalo, Donatella; Sitkovsky, Michail V; Filippini, Antonio; Riccioli, Anna

    2010-01-01

    Toll-like receptors (TLRs) recognize microbial/viral-derived components that trigger innate immune response and conflicting data implicate TLR agonists in cancer, either as protumor or antitumor agents. We previously demonstrated that TLR3 activation mediated by its agonist poly(I:C) induces antitumor signaling, leading to apoptosis of prostate cancer cells LNCaP and PC3 with much more efficiency in the former than in the second more aggressive line. The transcription factor hypoxia-inducible factor 1 (HIF-1) regulates several cellular processes, including apoptosis, in response to hypoxia and to other stimuli also in normoxic conditions. Here we describe a novel protumor machinery triggered by TLR3 activation in PC3 cells consisting of increased expression of the specific I.3 isoform of HIF-1α and nuclear accumulation of HIF-1 complex in normoxia, resulting in reduced apoptosis and in secretion of functional vascular endothelial growth factor (VEGF). Moreover, we report that, in the less aggressive LNCaP cells, TLR3 activation fails to induce nuclear accumulation of HIF-1α. However, the transfection of I.3 isoform of hif-1α in LNCaP cells allows poly(I:C)-induced HIF-1 activation, resulting in apoptosis protection and VEGF secretion. Altogether, our findings demonstrate that differences in the basal level of HIF-1α expression in different prostate cancer cell lines underlie their differential response to TLR3 activation, suggesting a correlation between different stages of malignancy, hypoxic gene expression, and beneficial responsiveness to TLR agonists. PMID:20651983

  20. Glutamate-induced apoptosis in primary cortical neurons is inhibited by equine estrogens via down-regulation of caspase-3 and prevention of mitochondrial cytochrome c release

    Directory of Open Access Journals (Sweden)

    Zhang YueMei

    2005-02-01

    Full Text Available Abstract Background Apoptosis plays a key role in cell death observed in neurodegenerative diseases marked by a progressive loss of neurons as seen in Alzheimer's disease. Although the exact cause of apoptosis is not known, a number of factors such as free radicals, insufficient levels of nerve growth factors and excessive levels of glutamate have been implicated. We and others, have previously reported that in a stable HT22 neuronal cell line, glutamate induces apoptosis as indicated by DNA fragmentation and up- and down-regulation of Bax (pro-apoptotic, and Bcl-2 (anti-apoptotic genes respectively. Furthermore, these changes were reversed/inhibited by estrogens. Several lines of evidence also indicate that a family of cysteine proteases (caspases appear to play a critical role in neuronal apoptosis. The purpose of the present study is to determine in primary cultures of cortical cells, if glutamate-induced neuronal apoptosis and its inhibition by estrogens involve changes in caspase-3 protease and whether this process is mediated by Fas receptor and/or mitochondrial signal transduction pathways involving release of cytochrome c. Results In primary cultures of rat cortical cells, glutamate induced apoptosis that was associated with enhanced DNA fragmentation, morphological changes, and up-regulation of pro-caspase-3. Exposure of cortical cells to glutamate resulted in a time-dependent cell death and an increase in caspase-3 protein levels. Although the increase in caspase-3 levels was evident after 3 h, cell death was only significantly increased after 6 h. Treatment of cells for 6 h with 1 to 20 mM glutamate resulted in a 35 to 45% cell death that was associated with a 45 to 65% increase in the expression of caspase-3 protein. Pretreatment with caspase-3-protease inhibitor z-DEVD or pan-caspase inhibitor z-VAD significantly decreased glutamate-induced cell death of cortical cells. Exposure of cells to glutamate for 6 h in the presence or

  1. Dichlorodiphenyltrichloroethane technical mixture regulates cell cycle and apoptosis genes through the activation of CAR and ERα in mouse livers

    Energy Technology Data Exchange (ETDEWEB)

    Kazantseva, Yuliya A.; Yarushkin, Andrei A. [Institute of Molecular Biology and Biophysics SB RAMS, Novosibirsk, Timakova str., 2, 630117 (Russian Federation); Pustylnyak, Vladimir O., E-mail: pustylnyak@ngs.ru [Institute of Molecular Biology and Biophysics SB RAMS, Novosibirsk, Timakova str., 2, 630117 (Russian Federation); Novosibirsk State University, Novosibirsk, Pirogova str., 2, 630090 (Russian Federation)

    2013-09-01

    Dichlorodiphenyltrichloroethane (DDT) is a widely used organochlorine pesticide and a xenoestrogen that promotes rodent hepatomegaly and tumours. A recent study has shown significant correlation between DDT serum concentration and liver cancer incidence in humans, but the underlying mechanisms remain elusive. We hypothesised that a mixture of DDT isomers could exert effects on the liver through pathways instead of classical ERs. The acute effects of a DDT mixture containing the two major isomers p,p′-DDT (85%) and o,p′-DDT (15%) on CAR and ERα receptors and their cell cycle and apoptosis target genes were studied in mouse livers. ChIP results demonstrated increased CAR and ERα recruitment to their specific target gene binding sites in response to the DDT mixture. The results of real-time RT-PCR were consistent with the ChIP data and demonstrated that the DDT was able to activate both CAR and ERα in mouse livers, leading to target gene transcriptional increases including Cyp2b10, Gadd45β, cMyc, Mdm2, Ccnd1, cFos and E2f1. Western blot analysis demonstrated increases in cell cycle progression proteins cMyc, Cyclin D1, CDK4 and E2f1 and anti-apoptosis proteins Mdm2 and Gadd45β. In addition, DDT exposure led to Rb phosphorylation. Increases in cell cycle progression and anti-apoptosis proteins were accompanied by a decrease in p53 content and its transcriptional activity. However, the DDT was unable to stimulate the β-catenin signalling pathway, which can play an important role in hepatocyte proliferation. Thus, our results indicate that DDT treatment may result in cell cycle progression and apoptosis inhibition through CAR- and ERα-mediated gene activation in mouse livers. These findings suggest that the proliferative and anti-apoptotic conditions induced by CAR and ERα activation may be important contributors to the early stages of hepatocarcinogenesis as produced by DDT in rodent livers. - Highlights: • DDT activated both CAR and ERα and their cell

  2. Glutathione, N-acetylcysteine and lipoic acid down-regulate starvation-induced apoptosis, RANKL/OPG ratio and sclerostin in osteocytes: involvement of JNK and ERK1/2 signalling.

    Science.gov (United States)

    Fontani, Filippo; Marcucci, Gemma; Iantomasi, Teresa; Brandi, Maria Luisa; Vincenzini, Maria Teresa

    2015-04-01

    Osteocyte apoptosis due to microdamage and/or oxidative stress is related to increased local bone turnover and resorption observed in various bone diseases. Previous data on osteoblasts and osteoclasts have linked reactive oxygen species and antioxidants to bone remodelling. This study performs a comprehensive analysis on the effect of antioxidants such as glutathione (GSH), N-acetylcysteine and lipoic acid (LA) on starvation-induced osteocyte apoptosis and on cytokines involved in bone remodelling such as the receptor activator kB ligand (RANKL), osteoprotegerin (OPG) and sclerostin. For this study, apoptosis was induced by serum starvation in a murine osteocyte-like cell line MLO-Y4; this condition mimics in part osteocyte apoptosis due to microdamage. The results show that starvation-induced apoptosis and expression of RANKL, OPG and sclerostin are redox regulated processes. All antioxidants are able to inhibit the apoptosis due to starvation. They down-regulate the expression and the release of RANKL, the expression of sclerostin and RANKL/OPG ratio, whereas they only in part up-regulate OPG expression. Antioxidants mediate their effect on starvation-induced apoptosis by JNK signalling and on cytokine expression by both JNK and ERK1/2 activities. This study shows the possible involvement of biological antioxidants such as GSH and LA on redox regulated mechanisms related to apoptosis and expression of cytokines involved in bone remodelling. Moreover, it suggests that both JNK and ERK1/2 may be useful biological targets for drugs affecting bone diseases associated with increased oxidative stress. PMID:25660312

  3. hNOA1 interacts with complex I and DAP3 and regulates mitochondrial respiration and apoptosis.

    OpenAIRE

    Tang, Tingdong; Zheng, Bin; Chen, Sheng-Hong; Murphy, Anne N.; Kudlicka, Krystyna; Zhou, Huilin; Farquhar, Marilyn G.

    2009-01-01

    Mitochondria are dynamic organelles that play key roles in metabolism, energy production, and apoptosis. Coordination of these processes is essential to maintain normal cellular functions. Here we characterized hNOA1, the human homologue of AtNOA1 (Arabidopsis thaliana nitric oxide-associated protein 1), a large mitochondrial GTPase. By immunofluorescence, immunoelectron microscopy, and mitochondrial subfractionation, endogenous hNOA1 is localized within mitochondria where it is peripherally ...

  4. hNOA1 Interacts with Complex I and DAP3 and Regulates Mitochondrial Respiration and Apoptosis*S⃞

    OpenAIRE

    Tang, Tingdong; Zheng, Bin; Chen, Sheng-Hong; Murphy, Anne N.; Kudlicka, Krystyna; Zhou, Huilin; Farquhar, Marilyn G.

    2009-01-01

    Mitochondria are dynamic organelles that play key roles in metabolism, energy production, and apoptosis. Coordination of these processes is essential to maintain normal cellular functions. Here we characterized hNOA1, the human homologue of AtNOA1 (Arabidopsis thaliana nitric oxide-associated protein 1), a large mitochondrial GTPase. By immunofluorescence, immunoelectron microscopy, and mitochondrial subfractionation, endogenous hNOA1 is localized within mitochondria w...

  5. MicroRNA-219-5p Inhibits Morphine-Induced Apoptosis by Targeting Key Cell Cycle Regulator WEE1.

    Science.gov (United States)

    Lou, Wei; Zhang, Xingwang; Hu, Xiao-Ying; Hu, Ai-Rong

    2016-01-01

    BACKGROUND To identify the effects of microRNA (miR)-219-5p on morphine-induced apoptosis by targeting WEE1. MATERIAL AND METHODS Forty Balb/C mice (Toll-like receptor 9, TLR9 knockout) were randomly allocated to the experimental and control groups (20 in each group). The baseline miR-219-5p expression was detected using quantitative real-time PCR (qRT-PCR). After morphine was injected at 6 h on the 2nd and 6th days, experimental and control groups received miR-219-5p mimics or miRNA-negative control (NC), respectively, compound injection. Tissues and cells were later obtained from subjects in each group separately after mice were killed. TUNEL assay was used to investigate apoptosis in both groups. RAW264.7 cells were treated with miR-219-5p mimics and controls, respectively. After 24 h, 10 μM of morphine was added at 24 h. Cell apoptosis was assessed by flow cytometer. The WEE1 and Phospho-cdc2 (Tyr15) expressions were examined by Western blotting. RESULTS MiR-219-5p expression in the experimental group was significantly lower than that in the control group (PWEE1 and Tyr15 protein expressions in the miR-219-5p NC group and morphine group were obviously stronger than those in the blank control group (all PWEE1 and Tyr15 protein expressions were significantly lower compared with those in the miR-219-5p NC group and morphine group (all PWEE1 to suppress Tyr15 expressions and activate Cdc2, thus inhibiting the morphine-induced macrophage apoptosis. PMID:27253431

  6. Taxol-induced unfolded protein response activation in breast cancer cells exposed to hypoxia: ATF4 activation regulates autophagy and inhibits apoptosis.

    Science.gov (United States)

    Notte, Annick; Rebucci, Magali; Fransolet, Maude; Roegiers, Edith; Genin, Marie; Tellier, Celine; Watillon, Kassandra; Fattaccioli, Antoine; Arnould, Thierry; Michiels, Carine

    2015-05-01

    Understanding the mechanisms responsible for the resistance against chemotherapy-induced cell death is still of great interest since the number of patients with cancer increases and relapse is commonly observed. Indeed, the development of hypoxic regions as well as UPR (unfolded protein response) activation is known to promote cancer cell adaptive responses to the stressful tumor microenvironment and resistance against anticancer therapies. Therefore, the impact of UPR combined to hypoxia on autophagy and apoptosis activation during taxol exposure was investigated in MDA-MB-231 and T47D breast cancer cells. The results showed that taxol rapidly induced UPR activation and that hypoxia modulated taxol-induced UPR activation differently according to the different UPR pathways (PERK, ATF6, and IRE1α). The putative involvement of these signaling pathways in autophagy or in apoptosis regulation in response to taxol exposure was investigated. However, while no link between the activation of these three ER stress sensors and autophagy or apoptosis regulation could be evidenced, results showed that ATF4 activation, which occurs independently of UPR activation, was involved in taxol-induced autophagy completion. In addition, an ATF4-dependent mechanism leading to cancer cell adaptation and resistance against taxol-induced cell death was evidenced. Finally, our results demonstrate that expression of ATF4, in association with hypoxia-induced genes, can be used as a biomarker of a poor prognosis for human breast cancer patients supporting the conclusion that ATF4 might play an important role in adaptation and resistance of breast cancer cells to chemotherapy in hypoxic tumors.

  7. MicroRNA-17-mediated down-regulation of apoptotic protease activating factor 1 attenuates apoptosome formation and subsequent apoptosis of cardiomyocytes.

    Science.gov (United States)

    Song, Seungjun; Seo, Hyang-Hee; Lee, Se-Yeon; Lee, Chang Yeon; Lee, Jiyun; Yoo, Kyung-Jong; Yoon, Cheesoon; Choi, Eunhyun; Hwang, Ki-Chul; Lee, Seahyoung

    2015-09-18

    Heart diseases such as myocardial infarction (MI) can damage individual cardiomyocytes, leading to the activation of cell death programs. The most scrutinized type of cell death in the heart is apoptosis, and one of the key events during the propagation of apoptotic signaling is the formation of apoptosomes, which relay apoptotic signals by activating caspase-9. As one of the major components of apoptosomes, apoptotic protease activating factor 1 (Apaf-1) facilitates the formation of apoptosomes containing cytochrome c (Cyto-c) and deoxyadenosine triphosphate (dATP). Thus, it may be possible to suppress the activation of the apoptotic program by down-regulating the expression of Apaf-1 using miRNAs. To validate this hypothesis, we selected a number of candidate miRNAs that were expected to target Apaf-1 based on miRNA target prediction databases. Among these candidate miRNAs, we empirically identified miR-17 as a novel Apaf-1-targeting miRNA. The delivery of exogenous miR-17 suppressed Apaf-1 expression and consequently attenuated formation of the apoptosome complex containing caspase-9, as demonstrated by co-immunoprecipitation and immunocytochemistry. Furthermore, miR-17 suppressed the cleavage of procaspase-9 and the subsequent activation of caspase-3, which is downstream of activated caspase-9. Cell viability tests also indicated that miR-17 pretreatment significantly prevented the norepinephrine-induced apoptosis of cardiomyocytes, suggesting that down-regulation of apoptosome formation may be an effective strategy to prevent cellular apoptosis. These results demonstrate the potential of miR-17 as an effective anti-apoptotic agent. PMID:26265044

  8. Up-regulation of Hsp27 by ERα/Sp1 facilitates proliferation and confers resistance to apoptosis in human papillary thyroid cancer cells.

    Science.gov (United States)

    Mo, Xiao-Mei; Li, Li; Zhu, Ping; Dai, Yu-Jie; Zhao, Ting-Ting; Liao, Ling-Yao; Chen, George G; Liu, Zhi-Min

    2016-08-15

    17β-estradiol (E2) has been suggested to play a role in the development and progression of papillary thyroid cancer. Heat shock protein 27 (Hsp27) is a member of the Hsp family that is responsible for cell survival under stressful conditions. Previous studies have shown that the 5'-promoter region of Hsp27 gene contains a specificity protein-1 (Spl) and estrogen response element half-site (ERE-half), which contributes to Hsp27 induction by E2 in breast cancer cells. However, it is unclear whether Hsp27 can be up-regulated by E2 and which estrogen receptor (ER) isoform and tethered transcription factor are involved in this regulation in papillary thyroid cancer cells. In the present study, we demonstrated that Hsp27 can be effectively up-regulated by E2 at mRNA and protein levels in human K1 and BCPAP papillary thyroid cancer cells which have more than two times higher level of ERα than that of ERβ. The up-regulation of Hsp27 by E2 is mediated by ERα/Sp1 and ERβ has repressive effect on this ERα/Sp1-mediated up-regulation of Hsp27. Moreover, we showed that the up-regulation of Hsp27 by ERα/Sp1 facilitates proliferation and confers resistance to apoptosis through interaction with procaspase-3. Targeting this pathway may be a potential strategy for therapy of papillary thyroid cancer. PMID:27179757

  9. Somatostatin and opioid receptors do not regulate proliferation or apoptosis of the human multiple myeloma U266 cells

    Directory of Open Access Journals (Sweden)

    Allouche Stéphane

    2009-06-01

    Full Text Available Abstract Background opioid and somatostatin receptors (SSTRs that can assemble as heterodimer were individually reported to modulate malignant cell proliferation and to favour apoptosis. Materials and methods: SSTRs and opioid receptors expression were examined by RT-PCR, western-blot and binding assays, cell proliferation was studied by XTT assay and propidium iodide (PI staining and apoptosis by annexin V-PI labelling. Results almost all human malignant haematological cell lines studied here expressed the five SSTRs. Further experiments were conducted on the human U266 multiple myeloma cells, which express also μ-opioid receptors (MOP-R. XTT assays and cell cycle studies provide no evidence for a significant effect upon opioid or somatostatin receptors stimulation. Furthermore, neither direct effect nor potentiation of the Fas-receptor pathway was detected on apoptosis after these treatments. Conclusion these data suggest that SSTRs or opioid receptors expression is not a guaranty for an anti-tumoral action in U266 cell line.

  10. 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

  11. Centrosomal Protein of 55 Regulates Glucose Metabolism, Proliferation and Apoptosis of Glioma Cells via the Akt/mTOR Signaling Pathway

    Science.gov (United States)

    Wang, Guangzhi; Liu, Mingna; Wang, Hongjun; Yu, Shan; Jiang, Zhenfeng; Sun, Jiahang; Han, Ke; Shen, Jia; Zhu, Minwei; Lin, Zhiguo; Jiang, Chuanlu; Guo, Mian

    2016-01-01

    Introduction: Glioma is one of the most common and most aggressive brain tumors in humans. The molecular and cellular mechanisms responsible for the onset and the progression of glioma are elusive and controversial. Centrosomal protein of 55 (CEP55) was initially described as a highly coiled-coil protein that plays critical roles in cell division, but was recently identified as being overexpressed in many human cancers. The function of CEP55 has not previously been characterized in glioma. We aim to discover the effect and mechanism of CEP55 in glioma development. Method: qRT-PCR and immunohistochemistry were used to analyze CEP55 expression. Glucose uptake, western blot, MTS, CCK-8, Caspase-3 activity and TUNEL staining assays were performed to investigate the role and mechanism of CEP55 on glioma cell process. Results: We found that the levels of CEP55 expression were upregulated in glioma. In addition, CEP55 appeared to regulate glucose metabolism of glioma cells. Furthermore, knockdown of CEP55 inhibited cell proliferation and induced cell apoptosis in glioma. Finally, we provided preliminary evidence that knockdown of CEP55 inhibited glioma development via suppressing the activity of Akt/mTOR signaling. Conclusions: Our results demonstrated that CEP55 regulates glucose metabolism, proliferation and apoptosis of glioma cells via the Akt/mTOR signaling pathway, and its promotive effect on glioma tumorigenesis can be a potential target for glioma therapy in the future. PMID:27471559

  12. An Ingenol Derived from Euphorbia kansui Induces Hepatocyte Cytotoxicity by Triggering G0/G1 Cell Cycle Arrest and Regulating the Mitochondrial Apoptosis Pathway in Vitro.

    Science.gov (United States)

    Yan, Xiaojing; Zhang, Li; Cao, Yudan; Yao, Weifeng; Tang, Yuping; Ding, Anwei

    2016-01-01

    Natural product lingenol, a purified diterpenoid compound derived from the root of Euphorbia kansui, exerts serious hepatotoxicity; however, the molecular mechanisms remain to be defined. In the present study, cell counting Kit-8 (CCK-8), inverted phase contrast microscope and flow cytometry were used to demonstrate that lingenol significantly inhibited L-O2 cells proliferation, and induced cell cycle arrest and apoptosis. Moreover, the results investigated that lingenol markedly disrupted mitochondrial functions by high content screening (HCS). In addition, the up-regulation of cytochrome c, AIF and Apaf-1 and activation of caspases were found in L-O2 cells detected by Western blotting and ELISA assay, which was required for lingenol activation of cytochrome c-mediated caspase cascades and AIF-mediated DNA damage. Mechanistic investigations revealed that lingenol significantly down-regulated the Bcl-2/Bax ratio and enhanced the reactive oxygen species (ROS) in L-O2 cells. These data collectively indicated that lingenol modulation of ROS and Bcl-2/Bax ratio led to cell cycle arrest and mitochondrial-mediated apoptosis in L-O2 cells in vitro. All of these results will be helpful to reveal the hepatotoxicity mechanism of Euphorbia kansui and to effectively guide safer and better clinical application of this herb. PMID:27338329

  13. Keratin impact on PKCδ- and ASMase-mediated regulation of hepatocyte lipid raft size - implication for FasR-associated apoptosis.

    Science.gov (United States)

    Gilbert, Stéphane; Loranger, Anne; Omary, M Bishr; Marceau, Normand

    2016-09-01

    Keratins are epithelial cell intermediate filament (IF) proteins that are expressed as pairs in a cell-differentiation-regulated manner. Hepatocytes express the keratin 8 and 18 pair (denoted K8/K18) of IFs, and a loss of K8 or K18, as in K8-null mice, leads to degradation of the keratin partner. We have previously reported that a K8/K18 loss in hepatocytes leads to altered cell surface lipid raft distribution and more efficient Fas receptor (FasR, also known as TNFRSF6)-mediated apoptosis. We demonstrate here that the absence of K8 or transgenic expression of the K8 G62C mutant in mouse hepatocytes reduces lipid raft size. Mechanistically, we find that the lipid raft size is dependent on acid sphingomyelinase (ASMase, also known as SMPD1) enzyme activity, which is reduced in absence of K8/K18. Notably, the reduction of ASMase activity appears to be caused by a less efficient redistribution of surface membrane PKCδ toward lysosomes. Moreover, we delineate the lipid raft volume range that is required for an optimal FasR-mediated apoptosis. Hence, K8/K18-dependent PKCδ- and ASMase-mediated modulation of lipid raft size can explain the more prominent FasR-mediated signaling resulting from K8/K18 loss. The fine-tuning of ASMase-mediated regulation of lipid rafts might provide a therapeutic target for death-receptor-related liver diseases.

  14. Nuclear envelope proteins Nesprin2 and LaminA regulate proliferation and apoptosis of vascular endothelial cells in response to shear stress.

    Science.gov (United States)

    Han, Yue; Wang, Lu; Yao, Qing-Ping; Zhang, Ping; Liu, Bo; Wang, Guo-Liang; Shen, Bao-Rong; Cheng, Binbin; Wang, Yingxiao; Jiang, Zong-Lai; Qi, Ying-Xin

    2015-05-01

    The dysfunction of vascular endothelial cells (ECs) influenced by flow shear stress is crucial for vascular remodeling. However, the roles of nuclear envelope (NE) proteins in shear stress-induced EC dysfunction are still unknown. Our results indicated that, compared with normal shear stress (NSS), low shear stress (LowSS) suppressed the expression of two types of NE proteins, Nesprin2 and LaminA, and increased the proliferation and apoptosis of ECs. Targeted small interfering RNA (siRNA) and gene overexpression plasmid transfection revealed that Nesprin2 and LaminA participate in the regulation of EC proliferation and apoptosis. A protein/DNA array was further used to detect the activation of transcription factors in ECs following transfection with target siRNAs and overexpression plasmids. The regulation of AP-2 and TFIID mediated by Nesprin2 and the activation of Stat-1, Stat-3, Stat-5 and Stat-6 by LaminA were verified under shear stress. Furthermore, using Ingenuity Pathway Analysis software and real-time RT-PCR, the effects of Nesprin2 or LaminA on the downstream target genes of AP-2, TFIID, and Stat-1, Stat-3, Stat-5 and Stat-6, respectively, were investigated under LowSS. Our study has revealed that NE proteins are novel mechano-sensitive molecules in ECs. LowSS suppresses the expression of Nesprin2 and LaminA, which may subsequently modulate the activation of important transcription factors and eventually lead to EC dysfunction.

  15. An Ingenol Derived from Euphorbia kansui Induces Hepatocyte Cytotoxicity by Triggering G0/G1 Cell Cycle Arrest and Regulating the Mitochondrial Apoptosis Pathway in Vitro

    Directory of Open Access Journals (Sweden)

    Xiaojing Yan

    2016-06-01

    Full Text Available Natural product lingenol, a purified diterpenoid compound derived from the root of Euphorbia kansui, exerts serious hepatotoxicity; however, the molecular mechanisms remain to be defined. In the present study, cell counting Kit-8 (CCK-8, inverted phase contrast microscope and flow cytometry were used to demonstrate that lingenol significantly inhibited L-O2 cells proliferation, and induced cell cycle arrest and apoptosis. Moreover, the results investigated that lingenol markedly disrupted mitochondrial functions by high content screening (HCS. In addition, the up-regulation of cytochrome c, AIF and Apaf-1 and activation of caspases were found in L-O2 cells detected by Western blotting and ELISA assay, which was required for lingenol activation of cytochrome c-mediated caspase cascades and AIF-mediated DNA damage. Mechanistic investigations revealed that lingenol significantly down-regulated the Bcl-2/Bax ratio and enhanced the reactive oxygen species (ROS in L-O2 cells. These data collectively indicated that lingenol modulation of ROS and Bcl-2/Bax ratio led to cell cycle arrest and mitochondrial-mediated apoptosis in L-O2 cells in vitro. All of these results will be helpful to reveal the hepatotoxicity mechanism of Euphorbia kansui and to effectively guide safer and better clinical application of this herb.

  16. Keratin impact on PKCδ- and ASMase-mediated regulation of hepatocyte lipid raft size - implication for FasR-associated apoptosis.

    Science.gov (United States)

    Gilbert, Stéphane; Loranger, Anne; Omary, M Bishr; Marceau, Normand

    2016-09-01

    Keratins are epithelial cell intermediate filament (IF) proteins that are expressed as pairs in a cell-differentiation-regulated manner. Hepatocytes express the keratin 8 and 18 pair (denoted K8/K18) of IFs, and a loss of K8 or K18, as in K8-null mice, leads to degradation of the keratin partner. We have previously reported that a K8/K18 loss in hepatocytes leads to altered cell surface lipid raft distribution and more efficient Fas receptor (FasR, also known as TNFRSF6)-mediated apoptosis. We demonstrate here that the absence of K8 or transgenic expression of the K8 G62C mutant in mouse hepatocytes reduces lipid raft size. Mechanistically, we find that the lipid raft size is dependent on acid sphingomyelinase (ASMase, also known as SMPD1) enzyme activity, which is reduced in absence of K8/K18. Notably, the reduction of ASMase activity appears to be caused by a less efficient redistribution of surface membrane PKCδ toward lysosomes. Moreover, we delineate the lipid raft volume range that is required for an optimal FasR-mediated apoptosis. Hence, K8/K18-dependent PKCδ- and ASMase-mediated modulation of lipid raft size can explain the more prominent FasR-mediated signaling resulting from K8/K18 loss. The fine-tuning of ASMase-mediated regulation of lipid rafts might provide a therapeutic target for death-receptor-related liver diseases. PMID:27422101

  17. The MAPK Signaling Cascade is a Central Hub in the Regulation of Cell Cycle, Apoptosis and Cytoskeleton Remodeling by Tripeptidyl-Peptidase II

    Directory of Open Access Journals (Sweden)

    Ramakrishna Sompallae

    2008-01-01

    Full Text Available Tripeptidyl-peptidase II (TPPII is a serine peptidase highly expressed in malignant Burkitt’s lymphoma cells (BL. We have previously shown that overexpression of TPPII correlates with chromosomal instability, centrosomal and mitotic spindle abnormalities and resistance to apoptosis induced by spindle poisons. Furthermore, TPPII knockdown by RNAi was associated with endoreplication and the accumulation of polynucleated cells that failed to complete cell division, indicating a role of TPPII in the cell cycle. Here we have applied a global approach of gene expression analysis to gain insights on the mechanism by which TPPII regulates this phenotype. mRNA profiling of control and TPPII knockdown BL cells identified one hundred and eighty five differentially expressed genes. Functional categorization of these genes high- lighted major physiological functions such as apoptosis, cell cycle progression, cytoskeleton remodeling, proteolysis, and signal transduction. Pathways and protein interactome analysis revealed a significant enrichment in components of MAP kinases signaling. These findings suggest that TPPII infl uences a wide network of signaling pathways that are regulated by MAPKs and exerts thereby a pleiotropic effect on biological processes associated with cell survival, proliferation and genomic instability.

  18. Curcumin-induced fibroblast apoptosis and in vitro wound contraction are regulated by antioxidants and heme oxygenase: implications for scar formation.

    NARCIS (Netherlands)

    Scharstuhl, A.; Mutsaers, H.A.M.; Pennings, S.W.C.; Szarek, W.A.; Russel, F.G.M.; Wagener, F.A.D.T.G.

    2009-01-01

    Fibroblast apoptosis plays a crucial role in normal and pathological scar formation and therefore we studied whether the putative apoptosis-inducing factor curcumin affects fibroblast apoptosis and may function as a novel therapeutic. We show that 25-microM curcumin causes fibroblast apoptosis and t

  19. Caspases: An apoptosis mediator

    Directory of Open Access Journals (Sweden)

    Tapan Kumar Palai

    2015-03-01

    Full Text Available The process of programmed cell death, or apoptosis, is generally characterized by distinct morphological characteristics and energy - dependent biochemical mechanisms. Apoptosis is a widely conserved phenomenon helping many processes, including normal cell turnover, proper development and functioning of the immune system, hormone dependent atrophy etc. Inappropriate apoptosis (either low level or high level leads to many developmental abnormalities like, neurodegenerative diseases, ischemic damage, autoimmune disorders and many types of cancer. To use cells for therapeutic purposes through generating cell lines, it is critical to study the cell cycle machinery and signalling pathways that controls cell death and apoptosis. Apoptotic pathways provide a fundamental protective mechanism that decreases cellular sensitivity to damaging events and allow proper developmental process in multi-cellular organisms. Major mediator of apoptosis is a family of proteins known as caspases. There are mainly fourteen types of caspases but out of them only ten caspasese have got essential role in controlling the process of apoptosis. These ten caspases have been categorized into either initiator caspases (caspase 2, 8, 9, 10 or executioner caspases (caspase 3, 6, 7. Although various types of caspases have been identified so far, the exact mechanisms of action of these groups of proteins is still to be fully understood. The aim of this review is to provide a detail overview of role of different caspases in regulating the process of apoptosis.

  20. Apoptosis in Pneumovirus Infection

    Directory of Open Access Journals (Sweden)

    Reinout A. Bem

    2013-01-01

    Full Text Available Pneumovirus infections cause a wide spectrum of respiratory disease in humans and animals. The airway epithelium is the major site of pneumovirus replication. Apoptosis or regulated cell death, may contribute to the host anti-viral response by limiting viral replication. However, apoptosis of lung epithelial cells may also exacerbate lung injury, depending on the extent, the timing and specific location in the lungs. Differential apoptotic responses of epithelial cells versus innate immune cells (e.g., neutrophils, macrophages during pneumovirus infection can further contribute to the complex and delicate balance between host defense and disease pathogenesis. The purpose of this manuscript is to give an overview of the role of apoptosis in pneumovirus infection. We will examine clinical and experimental data concerning the various pro-apoptotic stimuli and the roles of apoptotic epithelial and innate immune cells during pneumovirus disease. Finally, we will discuss potential therapeutic interventions targeting apoptosis in the lungs.

  1. Piceatannol promotes apoptosis via up-regulation of microRNA-129 expression in colorectal cancer cell lines

    International Nuclear Information System (INIS)

    Highlights: • Piceatannol induces apoptosis in cultured CRC cells. • Piceatannol promotes expression of miR-129. • miR-129 mediates proapoptotic effects of piceatannol. - Abstract: Piceatannol, a naturally occurring analog of resveratrol, has been confirmed as an antitumor agent by inhibiting proliferation, migration, and metastasis in diverse cancer. However, the effect and mechanisms of piceatannol on colorectal cancer (CRC) have not been well understood. This study aimed to test whether piceatannol could inhibit growth of CRC cells and reveal its underlying molecular mechanism. MTT assay was used to detect the cell viability in HCT116 and HT29 cells. Flow cytometry analysis was employed to measure apoptosis of CRC cells. Bcl-2, Bax and caspase-3 levels were analyzed by Western blot and miR-129 levels were determined by real-time RT-PCR. Our study showed that piceatannol inhibited HCT116 and HT29 cells growth in a concentration- and time-dependent manner. Piceatannol induced apoptosis by promoting expression of miR-129, and then inhibiting expression of Bcl-2, an known target for miR-129. Moreover, knock down of miR-129 could reverse the reduction of cell viability induced by piceatannol in HCT116 and HT29 cells. Taken together, our study unraveled the ability of piceatannol to suppress colorectal cancer growth and elucidated the participation of miR-129 in the anti-cancer action of piceatannol. Our findings suggest that piceatannol can be considered to be a promising anticancer agent for CRC

  2. Piceatannol promotes apoptosis via up-regulation of microRNA-129 expression in colorectal cancer cell lines

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Haogang [Department of General Surgery, The Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang 150081 (China); Jia, Ruichun [Department of Blood Transfusion, The Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang 150081 (China); Wang, Chunjing; Hu, Tianming [Department of General Surgery, The Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang 150081 (China); Wang, Fujing, E-mail: wangfujing-hyd@163.com [Department of General Surgery, The Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang 150081 (China)

    2014-09-26

    Highlights: • Piceatannol induces apoptosis in cultured CRC cells. • Piceatannol promotes expression of miR-129. • miR-129 mediates proapoptotic effects of piceatannol. - Abstract: Piceatannol, a naturally occurring analog of resveratrol, has been confirmed as an antitumor agent by inhibiting proliferation, migration, and metastasis in diverse cancer. However, the effect and mechanisms of piceatannol on colorectal cancer (CRC) have not been well understood. This study aimed to test whether piceatannol could inhibit growth of CRC cells and reveal its underlying molecular mechanism. MTT assay was used to detect the cell viability in HCT116 and HT29 cells. Flow cytometry analysis was employed to measure apoptosis of CRC cells. Bcl-2, Bax and caspase-3 levels were analyzed by Western blot and miR-129 levels were determined by real-time RT-PCR. Our study showed that piceatannol inhibited HCT116 and HT29 cells growth in a concentration- and time-dependent manner. Piceatannol induced apoptosis by promoting expression of miR-129, and then inhibiting expression of Bcl-2, an known target for miR-129. Moreover, knock down of miR-129 could reverse the reduction of cell viability induced by piceatannol in HCT116 and HT29 cells. Taken together, our study unraveled the ability of piceatannol to suppress colorectal cancer growth and elucidated the participation of miR-129 in the anti-cancer action of piceatannol. Our findings suggest that piceatannol can be considered to be a promising anticancer agent for CRC.

  3. Nox2 regulates endothelial cell cycle arrest and apoptosis via p21cip1 and p53

    OpenAIRE

    Li, Jian-Mei; Fan, Lampson M; George, Vinoj T.; Brooks, Gavin

    2007-01-01

    Endothelial cells (EC) express constitutively two major isoforms (Nox2 and Nox4) of the catalytic subunit of NADPH oxidase, which is a major source of endothelial reactive oxygen species. However, the individual roles of these Noxes in endothelial function remain unclear. We have investigated the role of Nox2 in nutrient deprivation-induced cell cycle arrest and apoptosis. In proliferating human dermal microvascular EC, Nox2 mRNA expression was low relative to Nox4 (Nox2:Nox4 ~1:13), but was ...

  4. Hepatopoietin Cn suppresses apoptosis of human hepatocellular carcinoma cells by up-regulating myeloid cell leukemia-1

    Institute of Scientific and Technical Information of China (English)

    Chu-Tse; Wu

    2010-01-01

    AIM:To investigate the role of hepatopoietin Cn(HPPCn) in apoptosis of hepatocellular carcinoma(HCC)cells and its mechanism. METHODS:Two human HCC cell lines,SMMC7721 and HepG2,were used in this study.Immunostaining, Western blotting and enzyme linked immunosorbent assay were conducted to identify the expression of HPPCn and the existence of an autocrine loop of HPPCn/ HPPCn receptor in SMMC7721 and HepG2.Apoptotic cells were detected using fluorescein isothiocyanate (FITC)-conjugated Annexin V and propidiu...

  5. Expression of progesterone receptor membrane component-2 within the immature rat ovary and its role in regulating mitosis and apoptosis of spontaneously immortalized granulosa cells.

    Science.gov (United States)

    Griffin, Daniel; Liu, Xiufang; Pru, Cindy; Pru, James K; Peluso, John J

    2014-08-01

    Progesterone receptor membrane component 2 (Pgrmc2) mRNA was detected in the immature rat ovary. By 48 h after eCG, Pgrmc2 mRNA levels decreased by 40% and were maintained at 48 h post-hCG. Immunohistochemical studies detected PGRMC2 in oocytes and ovarian surface epithelial, interstitial, thecal, granulosa, and luteal cells. PGRMC2 was also present in spontaneously immortalized granulosa cells, localizing to the cytoplasm of interphase cells and apparently to the mitotic spindle of cells in metaphase. Interestingly, PGRMC2 levels appeared to decrease during the G1 stage of the cell cycle. Moreover, overexpression of PGRMC2 suppressed entry into the cell cycle, possibly by binding the p58 form of cyclin dependent kinase 11b. Conversely, Pgrmc2 small interfering RNA (siRNA) treatment increased the percentage of cells in G1 and M stage but did not increase the number of cells, which was likely due to an increase in apoptosis. Depleting PGRMC2 did not inhibit cellular (3)H-progesterone binding, but attenuated the ability of progesterone to suppress mitosis and apoptosis. Taken together these studies suggest that PGRMC2 affects granulosa cell mitosis by acting at two specific stages of the cell cycle. First, PGRMC2 regulates the progression from the G0 into the G1 stage of the cell cycle. Second, PGRMC2 appears to localize to the mitotic spindle, where it likely promotes the final stages of mitosis. Finally, siRNA knockdown studies indicate that PGRMC2 is required for progesterone to slow the rate of granulosa cell mitosis and apoptosis. These findings support a role for PGRMC2 in ovarian follicle development.

  6. An ent-kaurane diterpenoid from Croton tonkinensis induces apoptosis by regulating AMP-activated protein kinase in SK-HEP1 human hepatocellular carcinoma cells.

    Science.gov (United States)

    Sul, Young Hoon; Lee, Myung Sun; Cha, Eun Young; Thuong, Phuong Thien; Khoi, Nguyen Minh; Song, In Sang

    2013-01-01

    Hepatocellular carcinoma (HCC) is the most common type of liver cancer with high mortality worldwide. Traditional chemotherapy for HCC is not widely accepted by clinical practitioners because of its toxic side effects. Thus, there is a need to identify chemotherapeutic drugs against HCC. AMP-activated protein kinase (AMPK) is a biologic sensor for cellular energy status that acts a tumor suppressor and a potential cancer therapeutic target. The traditional Vietnamese medicinal plant Croton tonkinensis shows cytotoxicity in various cancer cells; however, its anticancer mechanism remains unclear. In this study, we determined whether the ent-kaurane diterpenoid ent-18-acetoxy-7β-hydroxy kaur-15-oxo-16-ene (CrT1) isolated from this plant plays a role as a chemotherapeutic drug targeting AMPK. CrT1 blocked proliferation in dose- and time-dependent manners in human hepatocellular carcinoma SK-HEP1 cells. CrT1 induced sub-G(1) arrest and caspase-dependent apoptosis. CrT1 activated caspase-3, -7, -8, -9, and poly(ADP-ribose) polymerase, and its effect was inhibited by z-VAD-fmk suppressing caspase-3 cleavage. CrT1 induced increases in p53 and Bax levels but decreased Bcl(2) levels. In addition, CrT1 resulted in increased translocation of cytochrome c into the cytoplasm. We showed that CrT1-activated AMPK activation was followed by modulating the mammalian target of rapamycin/p70S6K pathway and was inactivated by treating cells with compound C. Treatment with CrT1 and aminoimidazole carboxamide ribonucleotide (AICAR) synergistically activated AMPK. CrT1-induced AMPK activation regulated cell viability and apoptosis. These results suggest that CrT1 is a novel AMPK activator and that AMPK activation in SK-HEP1 cells is responsible for CrT1-induced anticancer activity including apoptosis. PMID:23302650

  7. Sodium arsenite down-regulates the expression of X-linked inhibitor of apoptosis protein via translational and post-translational mechanisms in hepatocellular carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Hong; Hao, Yuqing; Wang, Lijing; Jia, Dongwei [Gene Research Center, Shanghai Medical College, Fudan University, Shanghai 200032 (China); Ruan, Yuanyuan, E-mail: yuanyuanruan@fudan.edu.cn [Gene Research Center, Shanghai Medical College, Fudan University, Shanghai 200032 (China); Gu, Jianxin [Gene Research Center, Shanghai Medical College, Fudan University, Shanghai 200032 (China)

    2012-06-15

    Highlights: Black-Right-Pointing-Pointer Sodium arsenite down-regulates the protein expression level of XIAP in HCC. Black-Right-Pointing-Pointer Sodium arsenite inhibits the de novo XIAP synthesis and its IRES activity. Black-Right-Pointing-Pointer Sodium arsenite decreases XIAP stability and promotes its proteasomal degradation. Black-Right-Pointing-Pointer Overexpression of XIAP attenuates the pro-apoptotic effect of sodium arsenite. -- Abstract: X-linked inhibitor of apoptosis protein (XIAP) is a member of the inhibitors of apoptosis protein (IAP) family, and has been reported to exhibit elevated expression levels in hepatocellular carcinoma (HCC) and promote cell survival, metastasis and tumor recurrence. Targeting XIAP has proven effective for the inhibition of cancer cell proliferation and restoration of cancer cell chemosensitivity. Arsenic (or sodium arsenite) is a potent anti-tumor agent used to treat patients with acute promyelocytic leukemia (APL). Additionally, arsenic induces cell growth inhibition, cell cycle arrest and apoptosis in human HCC cells. In this study, we identified XIAP as a target for sodium arsenite-induced cytotoxicity in HCC. The exposure of HCC cell lines to sodium arsenite resulted in inhibition of XIAP expression in both a dose- and time-dependent manner. Sodium arsenite blocked the de novo XIAP synthesis and the activity of its internal ribosome entry site (IRES) element. Moreover, treatment with sodium arsenite decreased the protein stability of XIAP and induced its ubiquitin-proteasomal degradation. Overexpression of XIAP attenuated the pro-apoptotic effect of sodium arsenite in HCC. Taken together, our data demonstrate that sodium arsenite suppresses XIAP expression via translational and post-translational mechanisms in HCC.

  8. Toll-like Receptor 3 Regulates Angiogenesis and Apoptosis in Prostate Cancer Cell Lines through Hypoxia-Inducible Factor 1α

    Directory of Open Access Journals (Sweden)

    Alessio Paone

    2010-07-01

    Full Text Available Toll-like receptors (TLRs recognize microbial/viral-derived components that trigger innate immune response and conflicting data implicate TLR agonists in cancer, either as protumor or antitumor agents. We previously demonstrated that TLR3 activation mediated by its agonist poly(I:C induces antitumor signaling, leading to apoptosis of prostate cancer cells LNCaP and PC3 with much more efficiency in the former than in the second more aggressive line. The transcription factor hypoxia-induciblefactor 1 (HIF-1regulates several cellular processes, includingapoptosis, in response to hypoxia and to other stimuli also in normoxic conditions. Here we describe a novel protumor machinery triggered by TLR3 activation in PC3 cells consisting of increased expression of the specific 1.3 isoform of HIF-1α and nuclear accumulation of HIF-1 complex in normoxia, resulting in reduced apoptosis and in secretion of functional vascular endothelial growth factor (VEGF. Moreover, we report that, in the less aggressive LNCaP cells, TLR3 activation fails to induce nuclear accumulation of HIF-1α. However, the transfection of 1.3 isoform of hif-1α in LNCaP cells allows poly(I:CI-induced HIF-1 activation, resulting in apoptosis protection and VEGF secretion. Altogether, our findings demonstrate that differences in the basal level of HIF-1α expression in different prostate cancer cell lines underlie their differential response to TLR3 activation, suggesting a correlation between different stages of malignancy, hypoxic gene expression, and beneficial responsiveness to TLR agonists.

  9. Caspase Family Proteases and Apoptosis

    Institute of Scientific and Technical Information of China (English)

    Ting-Jun FAN; Li-Hui HAN; Ri-Shan CONG; Jin LIANG

    2005-01-01

    Apoptosis, or programmed cell death, is an essential physiological process that plays a critical role in development and tissue homeostasis. The progress of apoptosis is regulated in an orderly way by a series of signal cascades under certain circumstances. The caspase-cascade system plays vital roles in the induction, transduction and amplification of intracellular apoptotic signals. Caspases, closely associated with apoptosis, are aspartate-specific cysteine proteases and members of the interleukin-1β-converting enzyme family. The activation and function of caspases, involved in the delicate caspase-cascade system, are regulated by various kinds of molecules, such as the inhibitor of apoptosis protein, Bcl-2 family proteins, calpain,and Ca2+. Based on the latest research, the members of the caspase family, caspase-cascade system and caspase-regulating molecules involved in apoptosis are reviewed.

  10. Methoxychlor and triclosan stimulates ovarian cancer growth by regulating cell cycle- and apoptosis-related genes via an estrogen receptor-dependent pathway.

    Science.gov (United States)

    Kim, Joo-Young; Yi, Bo-Rim; Go, Ryeo-Eun; Hwang, Kyung-A; Nam, Ki-Hoan; Choi, Kyung-Chul

    2014-05-01

    Methoxychlor and triclosan are emergent or suspected endocrine-disrupting chemicals (EDCs). Methoxychlor [MXC; 1,1,1-trichlor-2,2-bis (4-methoxyphenyl) ethane] is an organochlorine pesticide that has been primarily used since dichlorodiphenyltrichloroethane (DDT) was banned. In addition, triclosan (TCS) is used as a common component of soaps, deodorants, toothpastes, and other hygiene products at concentrations up to 0.3%. In the present study, the potential impact of MXC and TCS on ovarian cancer cell growth and underlying mechanism(s) was examined following their treatments in BG-1 ovarian cancer cells. As results, MXC and TCS induced BG-1 cell growth via regulating cyclin D1, p21 and Bax genes related with cell cycle and apoptosis. A methylthiazolyldiphenyl-tetrazolium bromide (MTT) assay confirmed that the proliferation of BG-1 ovarian cancer cells was stimulated by MXC (10(-6), 10(-7), 10(-8), and 10(-9)M) or TCS (10(-6), 10(-7), 10(-8), and 10(-9)M). Treatment of BG-1 cells with MXC or TCS resulted in the upregulation of cyclin D1 and downregulation of p21 and Bax transcriptions. In addition, the protein level of cyclin D1 was increased by MXC or TCS while p21 and Bax protein levels appeared to be reduced in these cells. Furthermore, MXC- or TCS-induced alterations of these genes were reversed in the presence of ICI 182,780 (10(-7)M), suggesting that the changes in these gene expressions may be regulated by an ER-dependent signaling pathway. In conclusion, the results of our investigation indicate that two potential EDCs, MXC and TCS, may stimulate ovarian cancer growth by regulating cell cycle- and apoptosis-related genes via an ER-dependent pathway.

  11. EGCG Inhibits Proliferation, Invasiveness and Tumor Growth by Up-Regulation of Adhesion Molecules, Suppression of Gelatinases Activity, and Induction of Apoptosis in Nasopharyngeal Carcinoma Cells

    Directory of Open Access Journals (Sweden)

    Chih-Yeu Fang

    2015-01-01

    Full Text Available (−-Epigallocatechin-3-gallate (EGCG, a major green tea polyphenol, has been shown to inhibit the proliferation of a variety of tumor cells. Epidemiological studies have shown that drinking green tea can reduce the incidence of nasopharyngeal carcinoma (NPC, yet the underlying mechanism is not well understood. In this study, the inhibitory effect of EGCG was tested on a set of Epstein Barr virus-negative and -positive NPC cell lines. Treatment with EGCG inhibited the proliferation of NPC cells but did not affect the growth of a non-malignant nasopharyngeal cell line, NP460hTert. Moreover, EGCG treated cells had reduced migration and invasive properties. The expression of the cell adhesion molecules E-cadherin and β-catenin was found to be up-regulated by EGCG treatment, while the down-regulation of matrix metalloproteinases (MMP-2 and MMP-9 were found to be mediated by suppression of extracellular signal-regulated kinase (ERK phosphorylation and AP-1 and Sp1 transactivation. Spheroid formation by NPC cells in suspension was significantly inhibited by EGCG. Oral administration of EGCG was capable of suppressing tumor growth in xenografted mice bearing NPC tumors. Treatment with EGCG was found to elevate the expression of p53 and p21, and eventually led to apoptosis of NPC cells via caspase 3 activation. The nuclear translocation of NF-κB and β-catenin was also suppressed by EGCG treatment. These results indicate that EGCG can inhibit the proliferation and invasiveness, and induce apoptosis, of NPC cells, making it a promising agent for chemoprevention or adjuvant therapy of NPC.

  12. Fibrates inhibit the apoptosis of Batten disease lymphoblast cells via autophagy recovery and regulation of mitochondrial membrane potential.

    Science.gov (United States)

    Hong, Minho; Song, Ki Duk; Lee, Hak-Kyo; Yi, SunShin; Lee, Yong Seok; Heo, Tae-Hwe; Jun, Hyun Sik; Kim, Sung-Jo

    2016-03-01

    Batten disease (BD; also known as juvenile neuronal ceroid lipofuscinosis) is a genetic disorder inherited as an autosomal recessive trait and is characterized by blindness, seizures, cognitive decline, and early death resulting from the inherited mutation of the CLN3 gene. Mitochondrial oxidative stress, endoplasmic reticulum (ER) stress, disrupted autophagy, and enhanced apoptosis have been suggested to play a role in BD pathogenesis. Fibrates, a class of lipid-lowering drugs that induce peroxisome proliferator-activated receptor-α (PPAR-α) activation, are the most commonly used PPAR agonists. Assuming that fibrates have a neuroprotective effect, we studied the effects of fibrates, fenofibrate, bezafibrate, and gemfibrozil on apoptosis, depolarization of mitochondrial membrane, and defective autophagy in BD lymphoblast cells. The viability of fibrate-treated BD lymphoblast cells increased to levels of normal lymphoblast cells. In addition, treatment with fibrates inhibited depolarization of mitochondrial membrane potential in BD lymphoblast cells. Defective autophagy in BD lymphoblast cells was normalized when treated with fibrates as indicated by increased acridine orange staining. The recovery of autophagy in BD lymphoblast cells is most likely attributed to the upregulation of autophagy proteins, lysosomal-associated membrane protein 1 (LAMP1), and LC3 I/II, after treatment with fibrates. This study therefore suggests that fibrates may have a therapeutic potential against BD. PMID:26659390

  13. LRF is an essential downstream target of GATA1 in erythroid development and regulates BIM-dependent apoptosis.

    Science.gov (United States)

    Maeda, Takahiro; Ito, Keisuke; Merghoub, Taha; Poliseno, Laura; Hobbs, Robin M; Wang, Guocan; Dong, Lin; Maeda, Manami; Dore, Louis C; Zelent, Arthur; Luzzatto, Lucio; Teruya-Feldstein, Julie; Weiss, Mitchell J; Pandolfi, Pier Paolo

    2009-10-01

    GATA-1-dependent transcription is essential for erythroid differentiation and maturation. Suppression of programmed cell death is also thought to be critical for this process; however, the link between these two features of erythropoiesis has remained elusive. Here, we show that the POZ-Krüppel family transcription factor, LRF (also known as Zbtb7a/Pokemon), is a direct target of GATA1 and plays an essential antiapoptotic role during terminal erythroid differentiation. We find that loss of Lrf leads to lethal anemia in embryos, due to increased apoptosis of late-stage erythroblasts. This programmed cell death is Arf and p53 independent and is instead mediated by upregulation of the proapoptotic factor Bim. We identify Lrf as a direct repressor of Bim transcription. In strong support of this mechanism, genetic Bim loss delays the lethality of Lrf-deficient embryos and rescues their anemia phenotype. Thus, our data define a key transcriptional cascade for effective erythropoiesis, whereby GATA-1 suppresses BIM-mediated apoptosis via LRF. PMID:19853566

  14. Down-Regulation of AKT Signalling by Ursolic Acid Induces Intrinsic Apoptosis and Sensitization to Doxorubicin in Soft Tissue Sarcoma.

    Directory of Open Access Journals (Sweden)

    Victor Hugo Villar

    Full Text Available Several important biological activities have been attributed to the pentacyclic triterpene ursolic acid (UA, being its antitumoral effect extensively studied in human adenocarcinomas. In this work, we focused on the efficacy and molecular mechanisms involved in the antitumoral effects of UA, as single agent or combined with doxorubicin (DXR, in human soft tissue sarcoma cells. UA (5-50 μM strongly inhibited (up to 80% the viability of STS cells at 24 h and its proliferation in soft agar, with higher concentrations increasing apoptotic death up to 30%. UA treatment (6-9 h strongly blocked the survival AKT/GSK3β/β-catenin signalling pathway, which led to a concomitant reduction of the anti-apoptotic proteins c-Myc and p21, altogether resulting in the activation of intrinsic apoptosis. Interestingly, UA at low concentrations (10-15 μM enhanced the antitumoral effects of DXR by up to 2-fold, while in parallel inhibiting DXR-induced AKT activation and p21 expression, two proteins implicated in antitumoral drug resistance and cell survival. In conclusion, UA is able to induce intrinsic apoptosis in human STS cells and also to sensitize these cells to DXR by blocking the AKT signalling pathway. Therefore, UA may have beneficial effects, if used as nutraceutical adjuvant during standard chemotherapy treatment of STS.

  15. Down-Regulation of AKT Signalling by Ursolic Acid Induces Intrinsic Apoptosis and Sensitization to Doxorubicin in Soft Tissue Sarcoma

    Science.gov (United States)

    Villar, Victor Hugo; Vögler, Oliver; Barceló, Francisca; Martín-Broto, Javier; Martínez-Serra, Jordi; Ruiz-Gutiérrez, Valentina; Alemany, Regina

    2016-01-01

    Several important biological activities have been attributed to the pentacyclic triterpene ursolic acid (UA), being its antitumoral effect extensively studied in human adenocarcinomas. In this work, we focused on the efficacy and molecular mechanisms involved in the antitumoral effects of UA, as single agent or combined with doxorubicin (DXR), in human soft tissue sarcoma cells. UA (5–50 μM) strongly inhibited (up to 80%) the viability of STS cells at 24 h and its proliferation in soft agar, with higher concentrations increasing apoptotic death up to 30%. UA treatment (6–9 h) strongly blocked the survival AKT/GSK3β/β-catenin signalling pathway, which led to a concomitant reduction of the anti-apoptotic proteins c-Myc and p21, altogether resulting in the activation of intrinsic apoptosis. Interestingly, UA at low concentrations (10–15 μM) enhanced the antitumoral effects of DXR by up to 2-fold, while in parallel inhibiting DXR-induced AKT activation and p21 expression, two proteins implicated in antitumoral drug resistance and cell survival. In conclusion, UA is able to induce intrinsic apoptosis in human STS cells and also to sensitize these cells to DXR by blocking the AKT signalling pathway. Therefore, UA may have beneficial effects, if used as nutraceutical adjuvant during standard chemotherapy treatment of STS. PMID:27219337

  16. Inhibitor of apoptosis proteins and apoptosis

    Institute of Scientific and Technical Information of China (English)

    Yunbo Wei; Tingjun Fan; Miaomiao Yu

    2008-01-01

    Apoptosis is a physiological cell death process that plays a critical role in development, homeostasis, and immune defense of multicellular animals. Inhibitor of apoptosis proteins (IAPs) constitute a family of proteins that possess between one and three baculovirus IAP repeats. Some of them also have a really interesting new gene finger domain, and can prevent cell death by binding and inhibiting active caspases, but are regulated by IAP antagonists. Some evidence also indicates that IAP can modulate the cell cycle and signal transduction. The three main factors, IAPs, IAP antagonists, and caspases, are involved in regulating the progress of apoptosis in many species. Many studies and assumptions have been focused on the anfractuous interactions between these three main factors to explore their real functional model in order to develop potential anticancer drugs.In this review, we describe the classification, molecular structures, and properties of IAPs and discuss the mechanisms of apoptosis. We also discuss the promising significance of clinical applications of IAPs in the diagnosis and treatment of malignancy.

  17. Heat shock protein 27 regulates oxidative stress-induced apoptosis in cardiomyocytes:mechanisms via reactive oxygen species generation and Akt activation

    Institute of Scientific and Technical Information of China (English)

    LIU Li; ZHANG Xiao-jin; JIANG Su-rong; DING Zheng-nian; DING Guo-xian; HUANG Jun; CHENG Yun-lin

    2007-01-01

    Background Increased reactive oxygen species(ROS)formation,which in turn promotes cardiomyocytes apoptosis,is associated with the pathogenesis and progression of various cardiac diseases such as ischemia and heart failure.Recent studies have shown that over expression of heat shock protein 27(Hsp27)confers resistance to cardiac ischemia/reperfusion injury.However,not much is known about the regulation of myocyte survival by Hsp27.Methods The rat cardiac cell line H9c2,with a stable overexpression of Hsp27,was established,with empty vector transfected H9c2 cells as controls.Following the cells challenged by Hydrogen Peroxide(H2O2),lactate dehydrogenase (LDH)release,apoptosis,intracellular ROS,cell morphology,mitochondrial transmembrane potential and the activation of serine/threonine kinase Akt were determined.Results Along with marked suppression of H2O2-induced injury by Hsp27 overexpression in H9c2 cells,ROS generation and the loss of mitochondrial membrane potential were also significantly depressed.Furthermore,augmented Akt activation was observed in Hsp27 overexpressed H9c2 cells following H2O2 exposure.Conclusions Hsp27 inhibits oxidative stress-induced H9c2 damage and inhibition of ROS generation and the augmentation of Akt activation may be involved in the protective signaling.

  18. Diallyl trisulfide-induced apoptosis in human prostate cancer cells involves c-Jun N-terminal kinase and extracellular-signal regulated kinase-mediated phosphorylation of Bcl-2.

    Science.gov (United States)

    Xiao, Dong; Choi, Sunga; Johnson, Daniel E; Vogel, Victor G; Johnson, Candace S; Trump, Donald L; Lee, Yong J; Singh, Shivendra V

    2004-07-22

    Garlic-derived organosulfides (OSCs) including diallyl trisulfide (DATS) are highly effective in affording protection against chemically induced cancer in animals. Evidence is also mounting to indicate that some naturally occurring OSCs can suppress proliferation of cancer cells by causing apoptosis, but the sequence of events leading to proapoptotic effect of OSCs is poorly defined. Using PC-3 and DU145 human prostate cancer cells as a model, we now demonstrate that DATS is a significantly more potent apoptosis inducer than diallyl sulfide (DAS) or diallyl disulfide (DADS). DATS-induced apoptosis in PC-3 cells was associated with phosphorylation of Bcl-2, reduced Bcl-2 : Bax interaction, and cleavage of procaspase-9 and -3. Bcl-2 overexpressing PC-3 cells were significantly more resistant to apoptosis induction by DATS compared with vector-transfected control cells. DATS treatment resulted in activation of extracellular-signal regulated kinase 1/2 (ERK1/2) and c-jun N-terminal kinase 1 (JNK1) and/or JNK2, but not p38 mitogen-activated protein kinase. Phosphorylation of Bcl-2 in DATS-treated PC-3 cells was fully blocked in the presence of JNK-specific inhibitor SP600125. Moreover, JNK inhibitor afforded significant protection against DATS-induced apoptosis in both cells. DATS-induced Bcl-2 phosphorylation and apoptosis were partially attenuated by pharmacological inhibition of ERK1/2 using PD98059 or U0126. Overexpression of catalase inhibited DATS-mediated activation of JNK1/2, but not ERK1/2, and apoptosis induction in DU145 cells suggesting involvement of hydrogen peroxide as a second messenger in DATS-induced apoptosis. In conclusion, our data point towards important roles for Bcl-2, JNK and ERK in DATS-induced apoptosis in human prostate cancer cells.

  19. Oridonin Up-regulates Expression of P21 and Induces Autophagy and Apoptosis in Human Prostate Cancer Cells

    Directory of Open Access Journals (Sweden)

    Xiang Li, Xiang Li, Jiaxiong Wang, Zaiyuan Ye, Ji-Cheng Li

    2012-01-01

    Full Text Available Background: Oridonin (ORI could inhibit the proliferation and induce apoptosis in various cancer cell lines. However, the mechanism is not fully understood.Methods: Human prostate cancer (HPC cells were cultured in vitro and cell viability was detected by the CCK-8 assay. The ultrastructure changes were observed under transmission electron microscope (TEM. Chemical staining with acridine orange (AO, MDC or DAPI was used to detect acidic vesicular organelles (AVOs and alternation of DNA. Expression of LC3 and P21 was detected by Western Blot. Apoptotic rates and cell cycle arrest were detected by FACS.Results: Our study demonstrated that after ORI treatment, the proliferations of human prostate cancer (HPC cell lines PC-3 and LNCaP were inhibited in a concentration and time-dependent manner. ORI induced cell cycle arrest at the G2/M phase. A large number of autophagosomes with double-membrane structure and acidic vesicular organelles (AVOs were detected in the cytoplasm of HPC cells treated with ORI for 24 hours. ORI resulted in the conversion of LC3-I to LC3-II and recruitment of LC3-II to the autophagosomal membranes. Autophagy inhibitor 3-methyladenine (3-MA reduced AVOs formation and inhibited LC3-I to LC3-II conversion. At 48 h, DNA fragmentation, chromatin condensation and disappearance of surface microvilli were detected in ORI-treated cells. ORI induced a significant increase in the number of apoptotic cells (PC-3: 5.4% to 27.0%, LNCaP: 5.3% to 31.0%. Promoting autophagy by nutrient starvation increased cell viability, while inhibition of autophagy by 3-MA promoted cell death. The expression of P21 was increased by ORI, which could be completely reversed by the inhibition of autophagy.Conclusions: Our findings indicated that autophagy occurred before the onset of apoptosis and protected cancer cells in ORI-treated HPC cells. P21 was involved in ORI-induced autophagy and apoptosis. Our results provide an experimental basis for understand

  20. Torilis japonica extract-generated intracellular ROS induces apoptosis by reducing the mitochondrial membrane potential via regulation of the AMPK-p38 MAPK signaling pathway in HCT116 colon cancer.

    Science.gov (United States)

    Kim, Guen Tae; Lee, Se Hee; Kim, Young Min

    2016-09-01

    Torilis japonica extract (TJE) has been reported to possess diverse medicinal properties including anti‑inflammatory and antibacterial activities. However, the precise mechanism of its anticancer effect is not understood. Thus, we evaluated the apoptotic effects of TJE and examined its underlying molecular mechanisms in HCT116 colorectal cancer cells. Our results show that TJE induces apoptosis through the generation of intracellular reactive oxygen species (ROS), and that it regulates the mitochondrial outer membrane potential via the AMPK/p38 MAPK signaling pathway. Importantly, ~50% of cancer cells have p53 mutations. Thus, the ability to induce apoptosis in a p53-independent manner would be of great value in cancer treatment. Our results show that not only does TJE regulate the AMPK/p38 signaling pathway, but it induces apoptosis in cells in which p53 has been knocked down using siRNA. Moreover, as in in vitro studies, TJE induced apoptosis and regulated apoptosis related-proteins in an HCT 116 xenograft model. Taken together, our results demonstrate that TJE, a natural compound that may provide a substitute for chemotherapeutic drugs, has potential as an anticancer agent. PMID:27314881

  1. Afatinib down-regulates MCL-1 expression through the PERK-eIF2α-ATF4 axis and leads to apoptosis in head and neck squamous cell carcinoma.

    Science.gov (United States)

    Liu, Xianfang; Lv, Zhenghua; Zou, Jidong; Liu, Xiuxiu; Ma, Juke; Wang, Jinhua; Sa, Na; Jing, Peihang; Xu, Wei

    2016-01-01

    Afatinib is the second generation of irreversible inhibitor of EGFR, HER2 and HER4, which has shown encouraging phase II and III clinical outcomes in the treatment of head and neck squamous cell carcinoma (HNSCC). However, the molecular mechanism of afatinib-induced apoptosis in HNSCC is poorly understood. In the present investigation, we discovered that down-regulation of MCL-1, an anti-apoptotic member of BCL-2 family, was responsible for afatinib-triggered apoptosis. And the inactivation of AKT-mTOR signaling caused by afatinib lead to translational inhibition of MCL-1 expression. As a crucial branch of ER stress, PERK-eIF2α-ATF4 axis was also stimulated in HNSCC cells after afatinib incubation. Silencing either eIF2α or ATF4 by siRNA transfection relieved afatinib-caused suppression of AKT-mTOR activity, attenuating MCL-1 down-regulation as well as subsequent apoptosis. Collectively, the results show that afatinib hampers AKT-mTOR activation by stimulating PERK-eIF2α-ATF4 signaling pathway, giving rise to MCL-1 down-regulation mediated apoptosis in HNSCC cells. Therefore, our findings reveal the elaborate molecular network of afatinib-induced apoptosis in HNSCC, which would provide substantial theoretical underpinnings for afatinib clinical application and highlight its promising prospect in HNSCC treatment. PMID:27648360

  2. A novel dual kinase function of the RET proto-oncogene negatively regulates activating transcription factor 4-mediated apoptosis.

    Science.gov (United States)

    Bagheri-Yarmand, Rozita; Sinha, Krishna M; Gururaj, Anupama E; Ahmed, Zamal; Rizvi, Yasmeen Q; Huang, Su-Chen; Ladbury, John E; Bogler, Oliver; Williams, Michelle D; Cote, Gilbert J; Gagel, Robert F

    2015-05-01

    The RET proto-oncogene, a tyrosine kinase receptor, is widely known for its essential role in cell survival. Germ line missense mutations, which give rise to constitutively active oncogenic RET, were found to cause multiple endocrine neoplasia type 2, a dominant inherited cancer syndrome that affects neuroendocrine organs. However, the mechanisms by which RET promotes cell survival and prevents cell death remain elusive. We demonstrate that in addition to cytoplasmic localization, RET is localized in the nucleus and functions as a tyrosine-threonine dual specificity kinase. Knockdown of RET by shRNA in medullary thyroid cancer-derived cells stimulated expression of activating transcription factor 4 (ATF4), a master transcription factor for stress-induced apoptosis, through activation of its target proapoptotic genes NOXA and PUMA. RET knockdown also increased sensitivity to cisplatin-induced apoptosis. We observed that RET physically interacted with and phosphorylated ATF4 at tyrosine and threonine residues. Indeed, RET kinase activity was required to inhibit the ATF4-dependent activation of the NOXA gene because the site-specific substitution mutations that block threonine phosphorylation increased ATF4 stability and activated its targets NOXA and PUMA. Moreover, chromatin immunoprecipitation assays revealed that ATF4 occupancy increased at the NOXA promoter in TT cells treated with tyrosine kinase inhibitors or the ATF4 inducer eeyarestatin as well as in RET-depleted TT cells. Together these findings reveal RET as a novel dual kinase with nuclear localization and provide mechanisms by which RET represses the proapoptotic genes through direct interaction with and phosphorylation-dependent inactivation of ATF4 during the pathogenesis of medullary thyroid cancer.

  3. Manumycin A induces apoptosis in malignant pleural mesothelioma through regulation of Sp1 and activation of the mitochondria-related apoptotic pathway.

    Science.gov (United States)

    Kim, Ka Hwi; Chae, Jung-Il; Oh, Hana; Cho, Jin Hyoung; Lee, Ra-Ham; Yoon, Goo; Cho, Seung-Sik; Cho, Young-Sik; Lee, Mee-Hyun; Liu, Kangdong; Lee, Hyun-Jeong; Shim, Jung-Hyun

    2016-07-01

    Manumycin A (Manu A) is a natural product isolated from Streptomyces parvulus and has been reported to have anti-carcinogenic and anti-biotic properties. However, neither its molecular mechanism nor its molecular targets are well understood. Thus, the aim of the present study was to explore the possibility that Manu A has cancer preventive and chemotherapeutic effects on malignant pleural mesothelioma (MPM) through regulation of Sp1 and induction of mitochondrial cell death pathway. Manu A inhibited the cell viability of MSTO-211H and H28 cells in a concentration‑dependent manner as determined by MTS assay. IC50 values were calculated as 8.3 and 4.3 µM in the MSTO-311H and H28 cells following 48 h incubation, respectively. Manu A induced a significant increase in apoptotic indices as shown by DAPI staining, Annexin V assay, multi-caspase activity and mitochondrial membrane potential assay. The downregulation of Sp1 mRNA and protein expression by Manu A led to apoptosis by suppressing Sp1-regulated proteins (cyclin D1, Mcl-1 and survivin). Manu A decreased the protein levels of BID, Bcl-xL and PARP while it increased Bax levels. Manu A caused depolarization of the mitochondrial membrane with induction of CHOP, DR4 and DR5. Our results demonstrated that Manu A exerted anticancer effects by inducing apoptosis via inhibition of the Sp1-related signaling pathway in human MPM. PMID:27176604

  4. Down-regulation of Sonic hedgehog signaling pathway activity is involved in 5-fluorouracil-induced apoptosis and motility inhibition in Hep3B cells

    Institute of Scientific and Technical Information of China (English)

    Qiyu Wang; Shuhong Huang; Ling Yang; Ling Zhao; Yuxia Yin; Zhongzhen Liu; Zheyu Chen; Hongwei Zhang

    2008-01-01

    The Sonic hedgehog (SHh) pathway plays a critical role in normal embryogenesis and carcinogenesis, but its function in cancer cells treated with 5-fluorouracil (5-FU) remains unknown. We examined the expression of a subset of SHh signaling pathway genes, including SHh, SMO, PTC1, Su(Fu) and HIP in human hepatocellular carcinoma (HCC) cell lines,Hep3B and HepG2, treated with 5-FU by reverse transcriptionpolymerase chain reaction. Using trypan blue analysis,3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and terminal deoxynucleotidyl transferase-mediated digoxigenin-dUTP nick-end labeling assay, we also detected the apoptosis of Hep3B cells resulting from the transfection of pCS2-Gli1 expression vector combined with 5-FU treatment.The motility of the cells was detected by scratch wound closure assay. The expression and subcellular location of PTC1 protein in Hep3B cells treated by 5-FU were also investigated by Western blot analysis and immunofluorescent microscopy. The results indicated that the expression of SHh pathway target molecules at both messenger RNA and protein levels are evidently down-regulated in Hep3B cells treated with 5-FU. The overexpression of Gli1 restores cell viability and, to some extent, the migration abilities inhibited by 5-FU.Furthermore, 5-FU treatment affects the subcellular localization of PTC1 protein, a key member in SHh signaling pathway. Our data showed that the down-regulation of SHh signaling pathway activity was involved in 5-FU-induced apoptosis and the inhibition of motility in hedgehog-activated HCC cell lines. This implies that the combination of SHh signaling pathway inhibitor and 5-FU-based chemotherapy might represent a more promising strategy against HCC.

  5. Long non-coding RNA MALAT-1 is downregulated in preeclampsia and regulates proliferation, apoptosis, migration and invasion of JEG-3 trophoblast cells.

    Science.gov (United States)

    Chen, Haiying; Meng, Tao; Liu, Xuemin; Sun, Manni; Tong, Chunxiao; Liu, Jing; Wang, He; Du, Juan

    2015-01-01

    Long non-coding RNA (lncRNA), as a newly identified subset of the transcriptome, has been implicated in a variety of physiological and pathological processes. Metastasis associated lung adenocarcinoma transcript-1 (MALAT-1), a lncRNA that was initially detected in the metastatic lung cancer, was reported to be overexpressed in placenta previa increta/percreta (I/P), which is caused by excessive trophoblast invasion. However, the role of MALAT-1 in the regulation of trophoblast behavior is not fully understood. In this study, we first examined the expression of MALAT-1 in the placentas from the patients with preeclampsia, the pathology of which is associated with inadequate trophoblast invasion, and found that the expression of MALAT-1 was downregulated in the preeclamptic placentas as compared to the normal placentas. We further investigated the function of MALAT-1 in JEG-3 trophoblast cell line using short interfering RNA (siRNA) against MALAT-1 transcripts. Silencing of MALAT-1 in JEG-3 cells suppressed proliferation and induced cell cycle arrest at G0/G1 phase. Reduced expression of MALAT-1 by RNA interference resulted in enhanced apoptosis in JEG-3 cells, accompanied with elevated levels of the pro-apoptotic proteins including cleaved caspase-3, cleaved caspase-9 and cleaved poly (ADP-ribose) polymerase-1 (PARP-1). Moreover, the migration rate and the invasiveness of JEG-3 cells were suppressed when MALAT-1 was downregulated. In summary, our results suggest that MALAT-1 may play an important role in the regulation of proliferation, cell cycle, apoptosis, migration and invasion of trophoblast cells, and under-expression of MALAT-1 during early placentation may be involved in the pathogenesis of preeclampsia.

  6. Down-regulation of 11β-hydroxysteroid dehydrogenase type 2 by bortezomib sensitizes Jurkat leukemia T cells against glucocorticoid-induced apoptosis.

    Directory of Open Access Journals (Sweden)

    Yi Tao

    Full Text Available 11β-Hydroxysteroid dehydrogenases type 2 (11β-HSD2, a key regulator for pre-receptor metabolism of glucocorticoids (GCs by converting active GC, cortisol, to inactive cortisone, has been shown to be present in a variety of tumors. But its expression and roles have rarely been discussed in hematological malignancies. Proteasome inhibitor bortezomib has been shown to not only possess antitumor effects but also potentiate the activity of other chemotherapeutics. In this study, we demonstrated that 11β-HSD2 was highly expressed in two GC-resistant T-cell leukemic cell lines Jurkat and Molt4. In contrast, no 11β-HSD2 expression was found in two GC-sensitive non-hodgkin lymphoma cell lines Daudi and Raji as well as normal peripheral blood T cells. Inhibition of 11β-HSD2 by 11β-HSD inhibitor 18β-glycyrrhetinic acid or 11β-HSD2 shRNA significantly increased cortisol-induced apoptosis in Jurkat cells. Additionally, pretreatment of Jurkat cells with low-dose bortezomib resulted in increased cellular sensitivity to GC as shown by elevated induction of apoptosis, more cells arrested at G1 stage and up-regulation of GC-induced leucine zipper which is an important mediator of GC action. Furthermore, we clarified that bortezomib could dose-dependently inhibit 11β-HSD2 messenger RNA and protein levels as well as activity (cortisol-cortisone conversion through p38 mitogen-activated protein kinase signaling pathway. Therefore, we suggest 11β-HSD2 is, at least partially if not all, responsible for impaired GC suppression in Jurkat cells and also indicate a novel mechanism by which proteasome inhibitor bortezomib may influence GC action.

  7. The sGC activator inhibits the proliferation and migration, promotes the apoptosis of human pulmonary arterial smooth muscle cells via the up regulation of plasminogen activator inhibitor-2

    International Nuclear Information System (INIS)

    Background: Different types of pulmonary hypertension (PH) share the same process of pulmonary vascular remodeling, the molecular mechanism of which is not entirely clarified by far. The abnormal biological behaviors of pulmonary arterial smooth muscle cells (PASMCs) play an important role in this process. Objectives: We investigated the regulation of plasminogen activator inhibitor-2 (PAI-2) by the sGC activator, and explored the effect of PAI-2 on PASMCs proliferation, apoptosis and migration. Methods: After the transfection with PAI-2 overexpression vector and specific siRNAs or treatment with BAY 41-2272 (an activator of sGC), the mRNA and protein levels of PAI-2 in cultured human PASMCs were detected, and the proliferation, apoptosis and migration of PASMCs were investigated. Results: BAY 41-2272 up regulated the endogenous PAI-2 in PASMCs, on the mRNA and protein level. In PAI-2 overexpression group, the proliferation and migration of PASMCs were inhibited significantly, and the apoptosis of PASMCs was increased. In contrast, PAI-2 knockdown with siRNA increased PASMCs proliferation and migration, inhibited the apoptosis. Conclusions: PAI-2 overexpression inhibits the proliferation and migration and promotes the apoptosis of human PASMCs. Therefore, sGC activator might alleviate or reverse vascular remodeling in PH through the up-regulation of PAI-2. - Highlights: • sGC activator BAY41-2272 up regulated PAI-2 in PASMCs, on the mRNA and protein level. • PAI-2 overexpression inhibits the proliferation and migration of human PASMCs. • PAI-2 overexpression promotes the apoptosis of human PASMCs. • sGC activator might alleviate the vascular remodeling in pulmonary hypertension

  8. The sGC activator inhibits the proliferation and migration, promotes the apoptosis of human pulmonary arterial smooth muscle cells via the up regulation of plasminogen activator inhibitor-2

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Shuai [Beijing Institute of Respiratory Medicine, Beijing Chao-yang Hospital, Capital Medical University, 8 Gongti South Rd, Beijing (China); Beijing Key Laboratory of Respiratory and Pulmonary Circulation Disorders, 8 Gongti South Rd, Beijing (China); Zou, Lihui [Institute of Geriatrics, Beijing Hospital, 1 Dahua Rd, Beijing (China); National Clinical Research Center for Respiratory Diseases, 1 Dahua Rd, Beijing (China); Yang, Ting; Yang, Yuanhua; Zhai, Zhenguo [Beijing Institute of Respiratory Medicine, Beijing Chao-yang Hospital, Capital Medical University, 8 Gongti South Rd, Beijing (China); Beijing Key Laboratory of Respiratory and Pulmonary Circulation Disorders, 8 Gongti South Rd, Beijing (China); Xiao, Fei [Institute of Geriatrics, Beijing Hospital, 1 Dahua Rd, Beijing (China); National Clinical Research Center for Respiratory Diseases, 1 Dahua Rd, Beijing (China); Wang, Chen, E-mail: chenwangcjfh@163.com [Beijing Institute of Respiratory Medicine, Beijing Chao-yang Hospital, Capital Medical University, 8 Gongti South Rd, Beijing (China); Beijing Key Laboratory of Respiratory and Pulmonary Circulation Disorders, 8 Gongti South Rd, Beijing (China); National Clinical Research Center for Respiratory Diseases, 1 Dahua Rd, Beijing (China)

    2015-03-15

    Background: Different types of pulmonary hypertension (PH) share the same process of pulmonary vascular remodeling, the molecular mechanism of which is not entirely clarified by far. The abnormal biological behaviors of pulmonary arterial smooth muscle cells (PASMCs) play an important role in this process. Objectives: We investigated the regulation of plasminogen activator inhibitor-2 (PAI-2) by the sGC activator, and explored the effect of PAI-2 on PASMCs proliferation, apoptosis and migration. Methods: After the transfection with PAI-2 overexpression vector and specific siRNAs or treatment with BAY 41-2272 (an activator of sGC), the mRNA and protein levels of PAI-2 in cultured human PASMCs were detected, and the proliferation, apoptosis and migration of PASMCs were investigated. Results: BAY 41-2272 up regulated the endogenous PAI-2 in PASMCs, on the mRNA and protein level. In PAI-2 overexpression group, the proliferation and migration of PASMCs were inhibited significantly, and the apoptosis of PASMCs was increased. In contrast, PAI-2 knockdown with siRNA increased PASMCs proliferation and migration, inhibited the apoptosis. Conclusions: PAI-2 overexpression inhibits the proliferation and migration and promotes the apoptosis of human PASMCs. Therefore, sGC activator might alleviate or reverse vascular remodeling in PH through the up-regulation of PAI-2. - Highlights: • sGC activator BAY41-2272 up regulated PAI-2 in PASMCs, on the mRNA and protein level. • PAI-2 overexpression inhibits the proliferation and migration of human PASMCs. • PAI-2 overexpression promotes the apoptosis of human PASMCs. • sGC activator might alleviate the vascular remodeling in pulmonary hypertension.

  9. Association between Up-regulation of Fas Ligand Expression and Apoptosis of Tumor-infiltrating Lymphocytes in Human Breast Cancer

    Institute of Scientific and Technical Information of China (English)

    CHENG Bo

    2006-01-01

    In order to study the significance of FasL expression in immune escape of breast cancer,FasL protein expression and the number of tumor-infiltrating lymphocytes (TILs) in 40 specimens of breast cancer were detected by immunohistochemitry. The expression of FasL mRNA was measured by in situ hybridization in the consecutive tissue slices of 40 breast cancers respectively. By using terminal deoxynucleotidyl transferase-mediaed dUTP nick end labeling (TUNEL), apoptotic cells were detected in 40 specimens of breast cancer. The expression of FasL was detected in all 40 specimens to varying degrees. In the consecutive tissue slices, the location of expression of FasL protein corresponded with that of FasL mRNA. In those with FasL extensive expression, the number of TILs was less (P<0.05), the apoptotic index (AI) of TILs was higher and the AI of tumor cells was lower (P<0.01) than those with FasL weak expression respectively. The AI of TILs was correlated with that of tumor cells (r=-0.629, P<0.01). In conclusion, breast cancer cells can induce the apoptosis of TILs through the expression of FasL, which can counterattack the immune system. This may be a mechanism of immune evasion in breast cancer.

  10. Phytometabolite Dehydroleucodine Induces Cell Cycle Arrest, Apoptosis, and DNA Damage in Human Astrocytoma Cells through p73/p53 Regulation.

    Directory of Open Access Journals (Sweden)

    Natalia Bailon-Moscoso

    Full Text Available Accumulating evidence supports the idea that secondary metabolites obtained from medicinal plants (phytometabolites may be important contributors in the development of new chemotherapeutic agents to reduce the occurrence or recurrence of cancer. Our study focused on Dehydroleucodine (DhL, a sesquiterpene found in the provinces of Loja and Zamora-Chinchipe. In this study, we showed that DhL displayed cytostatic and cytotoxic activities on the human cerebral astrocytoma D384 cell line. With lactone isolated from Gynoxys verrucosa Wedd, a medicinal plant from Ecuador, we found that DhL induced cell death in D384 cells by triggering cell cycle arrest and inducing apoptosis and DNA damage. We further found that the cell death resulted in the increased expression of CDKN1A and BAX proteins. A marked induction of the levels of total TP73 and phosphorylated TP53, TP73, and γ-H2AX proteins was observed in D384 cells exposed to DhL, but no increase in total TP53 levels was detected. Overall these studies demonstrated the marked effect of DhL on the diminished survival of human astrocytoma cells through the induced expression of TP73 and phosphorylation of TP73 and TP53, suggesting their key roles in the tumor cell response to DhL treatment.

  11. Stage-specific expression of TNFα regulates bad/bid-mediated apoptosis and RIP1/ROS-mediated secondary necrosis in Birnavirus-infected fish cells.

    Directory of Open Access Journals (Sweden)

    Wei-Lun Wang

    Full Text Available Infectious pancreatic necrosis virus (IPNV can induce Bad-mediated apoptosis followed by secondary necrosis in fish cells, but it is not known how these two types of cell death are regulated by IPNV. We found that IPNV infection can regulate Bad/Bid-mediated apoptotic and Rip1/ROS-mediated necrotic death pathways via the up-regulation of TNFα in zebrafish ZF4 cells. Using a DNA microarray and quantitative RT-PCR analyses, two major subsets of differentially expressed genes were characterized, including the innate immune response gene TNFα and the pro-apoptotic genes Bad and Bid. In the early replication stage (0-6 h post-infection, or p.i., we observed that the pro-inflammatory cytokine TNFα underwent a rapid six-fold induction. Then, during the early-middle replication stages (6-12 h p.i., TNFα level was eight-fold induction and the pro-apoptotic Bcl-2 family members Bad and Bid were up-regulated. Furthermore, specific inhibitors of TNFα expression (AG-126 or TNFα-specific siRNA were used to block apoptotic and necrotic death signaling during the early or early-middle stages of IPNV infection. Inhibition of TNFα expression dramatically reduced the Bad/Bid-mediated apoptotic and Rip1/ROS-mediated necrotic cell death pathways and rescued host cell viability. Moreover, we used Rip1-specific inhibitors (Nec-1 and Rip1-specific siRNA to block Rip1 expression. The Rip1/ROS-mediated secondary necrotic pathway appeared to be reduced in IPNV-infected fish cells during the middle-late stage of infection (12-18 h p.i.. Taken together, our results indicate that IPNV triggers two death pathways via up-stream induction of the pro-inflammatory cytokine TNFα, and these results may provide new insights into the pathogenesis of RNA viruses.

  12. Ligation of cancer cell surface GRP78 with antibodies directed against its COOH-terminal domain up-regulates p53 activity and promotes apoptosis.

    Science.gov (United States)

    Misra, Uma Kant; Mowery, Yvonne; Kaczowka, Steven; Pizzo, Salvatore Vincent

    2009-05-01

    Binding of activated α(2)-macroglobulin to GRP78 on the surface of human prostate cancer cells promotes proliferation by activating signaling cascades. Autoantibodies directed against the activated α(2)-macroglobulin binding site in the NH(2)-terminal domain of GRP78 are receptor agonists, and their presence in the sera of cancer patients is a poor prognostic indicator. We now show that antibodies directed against the GRP78 COOH-terminal domain inhibit [(3)H]thymidine uptake and cellular proliferation while promoting apoptosis as measured by DNA fragmentation, Annexin V assay, and clonogenic assay. These antibodies are receptor antagonists blocking autophosphorylation and activation of GRP78. Using 1-LN and DU145 prostate cancer cell lines and A375 melanoma cells, which express GRP78 on their cell surface, we show that antibodies directed against the COOH-terminal domain of GRP78 up-regulate the tumor suppressor protein p53. By contrast, antibody directed against the NH(2)-terminal domain of GRP78 shows negligible effects on p53 expression. PC-3 prostate cancer cells, which do not express GRP78 on their cell surface, are refractory to the effects of anti-GRP78 antibodies directed against either the COOH- or NH(2)-terminal domains. However, overexpression of GRP78 in PC-3 cells causes translocation of GRP78 to the cell surface and promotes apoptosis when these cells are treated with antibody directed against its COOH-terminal domain. Silencing GRP78 or p53 expression by RNA interference significantly blocked the increase in p53 induced by antibodies. Antibodies directed against the COOH-terminal domain may play a therapeutic role in cancer patients whose tumors trigger the production of autoantibodies directed against the NH(2)-terminal domain of GRP78.

  13. Oridonin induces apoptosis and senescence in colorectal cancer cells by increasing histone hyperacetylation and regulation of p16, p21, p27 and c-myc

    International Nuclear Information System (INIS)

    Oridonin, a tetracycline diterpenoid compound, has the potential antitumor activities. Here, we evaluate the antitumor activity and action mechanisms of oridonin in colorectal cancer. Effects of oridonin on cell proliferation were determined by using a CCK-8 Kit. Cell cycle distribution was determined by flow cytometry. Apoptosis was examined by analyzing subdiploid population and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling assay. Senescent cells were determined by senescence-associated β-galactosidase activity analysis. Semi-quantitative RT-PCR was used to examine the changes of mRNA of p16, p21, p27 and c-myc. The concomitant changes of protein expression were analyzed with Western blot. Expression of AcH3 and AcH4 were examined by immunofluorescence staining and Western blots. Effects of oridonin on colony formation of SW1116 were examined by Soft Agar assay. The in vivo efficacy of oridonin was detected using a xenograft colorectal cancer model in nude mice. Oridonin induced potent growth inhibition, cell cycle arrest, apoptosis, senescence and colony-forming inhibition in three colorectal cancer cell lines in a dose-dependent manner in vitro. Daily i.p. injection of oridonin (6.25, 12.5 or 25 mg/kg) for 28 days significantly inhibited the growth of SW1116 s.c. xenografts in BABL/C nude mice. With western blot and reverse transcription-PCR, we further showed that the antitumor activities of oridonin correlated with induction of histone (H3 and H4) hyperacetylation, activation of p21, p27 and p16, and suppression of c-myc expression. Oridonin possesses potent in vitro and in vivo anti-colorectal cancer activities that correlated with induction of histone hyperacetylation and regulation of pathways critical for maintaining growth inhibition and cell cycle arrest. Therefore, oridonin may represent a novel therapeutic option in colorectal cancer treatment

  14. Oridonin induces apoptosis and senescence in colorectal cancer cells by increasing histone hyperacetylation and regulation of p16, p21, p27 and c-myc

    Directory of Open Access Journals (Sweden)

    Zhao Ying-Zheng

    2010-11-01

    Full Text Available Abstract Background Oridonin, a tetracycline diterpenoid compound, has the potential antitumor activities. Here, we evaluate the antitumor activity and action mechanisms of oridonin in colorectal cancer. Methods Effects of oridonin on cell proliferation were determined by using a CCK-8 Kit. Cell cycle distribution was determined by flow cytometry. Apoptosis was examined by analyzing subdiploid population and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling assay. Senescent cells were determined by senescence-associated β-galactosidase activity analysis. Semi-quantitative RT-PCR was used to examine the changes of mRNA of p16, p21, p27 and c-myc. The concomitant changes of protein expression were analyzed with Western blot. Expression of AcH3 and AcH4 were examined by immunofluorescence staining and Western blots. Effects of oridonin on colony formation of SW1116 were examined by Soft Agar assay. The in vivo efficacy of oridonin was detected using a xenograft colorectal cancer model in nude mice. Results Oridonin induced potent growth inhibition, cell cycle arrest, apoptosis, senescence and colony-forming inhibition in three colorectal cancer cell lines in a dose-dependent manner in vitro. Daily i.p. injection of oridonin (6.25, 12.5 or 25 mg/kg for 28 days significantly inhibited the growth of SW1116 s.c. xenografts in BABL/C nude mice. With western blot and reverse transcription-PCR, we further showed that the antitumor activities of oridonin correlated with induction of histone (H3 and H4 hyperacetylation, activation of p21, p27 and p16, and suppression of c-myc expression. Conclusion Oridonin possesses potent in vitro and in vivo anti-colorectal cancer activities that correlated with induction of histone hyperacetylation and regulation of pathways critical for maintaining growth inhibition and cell cycle arrest. Therefore, oridonin may represent a novel therapeutic option in colorectal cancer treatment.

  15. Advanced glycation end-products induce apoptosis in pancreatic islet endothelial cells via NF-κB-activated cyclooxygenase-2/prostaglandin E2 up-regulation.

    Directory of Open Access Journals (Sweden)

    Kuo-Cheng Lan

    Full Text Available Microvascular complications eventually affect nearly all patients with diabetes. Advanced glycation end-products (AGEs resulting from hyperglycemia are a complex and heterogeneous group of compounds that accumulate in the plasma and tissues in diabetic patients. They are responsible for both endothelial dysfunction and diabetic vasculopathy. The aim of this study was to investigate the cytotoxicity of AGEs on pancreatic islet microvascular endothelial cells. The mechanism underlying the apoptotic effect of AGEs in pancreatic islet endothelial cell line MS1 was explored. The results showed that AGEs significantly decreased MS1 cell viability and induced MS1 cell apoptosis in a dose-dependent manner. AGEs dose-dependently increased the expressions of cleaved caspase-3, and cleaved poly (ADP-ribose polymerase in MS1 cells. Treatment of MS1 cells with AGEs also resulted in increased nuclear factor (NF-κB-p65 phosphorylation and cyclooxygenase (COX-2 expression. However, AGEs did not affect the expressions of endoplasmic reticulum (ER stress-related molecules in MS1 cells. Pretreatment with NS398 (a COX-2 inhibitor to inhibit prostaglandin E2 (PGE2 production reversed the induction of cleaved caspase-3, cleaved PARP, and MS1 cell viability. Moreover, AGEs significantly increased the receptor for AGEs (RAGE protein expression in MS1 cells, which could be reversed by RAGE neutralizing antibody. RAGE Neutralizing antibody could also reverse the induction of cleaved caspase-3 and cleaved PARP and decreased cell viability induced by AGEs. These results implicate the involvement of NF-κB-activated COX-2/PGE2 up-regulation in AGEs/RAGE-induced islet endothelial cell apoptosis and cytotoxicity. These findings may provide insight into the pathological processes within the pancreatic islet microvasculature induced by AGEs accumulation.

  16. Norovirus regulation of the innate immune response and apoptosis occurs via the product of the alternative open reading frame 4.

    Directory of Open Access Journals (Sweden)

    Nora McFadden

    2011-12-01

    Full Text Available Small RNA viruses have evolved many mechanisms to increase the capacity of their short genomes. Here we describe the identification and characterization of a novel open reading frame (ORF4 encoded by the murine norovirus (MNV subgenomic RNA, in an alternative reading frame overlapping the VP1 coding region. ORF4 is translated during virus infection and the resultant protein localizes predominantly to the mitochondria. Using reverse genetics we demonstrated that expression of ORF4 is not required for virus replication in tissue culture but its loss results in a fitness cost since viruses lacking the ability to express ORF4 restore expression upon repeated passage in tissue culture. Functional analysis indicated that the protein produced from ORF4 antagonizes the innate immune response to infection by delaying the upregulation of a number of cellular genes activated by the innate pathway, including IFN-Beta. Apoptosis in the RAW264.7 macrophage cell line was also increased during virus infection in the absence of ORF4 expression. In vivo analysis of the WT and mutant virus lacking the ability to express ORF4 demonstrated an important role for ORF4 expression in infection and virulence. STAT1-/- mice infected with a virus lacking the ability to express ORF4 showed a delay in the onset of clinical signs when compared to mice infected with WT virus. Quantitative PCR and histopathological analysis of samples from these infected mice demonstrated that infection with a virus not expressing ORF4 results in a delayed infection in this system. In light of these findings we propose the name virulence factor 1, VF1 for this protein. The identification of VF1 represents the first characterization of an alternative open reading frame protein for the calicivirus family. The immune regulatory function of the MNV VF1 protein provide important perspectives for future research into norovirus biology and pathogenesis.

  17. Resveratrol and clofarabine induces a preferential apoptosis-activating effect on malignant mesothelioma cells by Mcl-1 down-regulation and caspase-3 activation.

    Science.gov (United States)

    Lee, Yoon-Jin; Lee, Yong-Jin; Lee, Sang-Han

    2015-03-01

    We previously demonstrated that resveratrol and clofarabine elicited a marked cytotoxicity on malignant mesothelioma (MM) MSTO-211H cells but not on the corresponding normal mesothelial MeT-5A cells. Little is known of the possible molecules that could be used to predict preferential chemosensitivity on MSTO-211H cells. Resveratrol and clofarabine induced down-regulation of Mcl-1 protein level in MSTO-211H cells. Treatment of cells with cycloheximide in the presence of proteasome inhibitor MG132 suggested that Mcl-1 protein levels were regulated at the post-translational step. The siRNA-based knockdown of Mcl-1 in MSTO-211H cells triggered more growth-inhibiting and apoptosis-inducing effects with the resultant cleavages of procaspase-3 and its substrate PARP, increased caspase-3/7 activity, and increased percentage of apoptotic propensities. However, the majority of the observed changes were not shown in MeT-5A cells. Collectively, these studies indicate that the preferential activation of caspase cascade in malignant cells might have important applications as a therapeutic target for MM. PMID:24924397

  18. The Role of AKT/mTOR Pathway in Stress Response to UV-Irradiation: Implication in Skin Carcinogenesis by Regulation of Apoptosis, Autophagy and Senescence

    Directory of Open Access Journals (Sweden)

    Elwira Strozyk

    2013-07-01

    Full Text Available Induction of DNA damage by UVB and UVA radiation may generate mutations and genomic instability leading to carcinogenesis. Therefore, skin cells being repeatedly exposed to ultraviolet (UV light have acquired multilayered protective mechanisms to avoid malignant transformation. Besides extensive DNA repair mechanisms, the damaged skin cells can be eliminated by induction of apoptosis, which is mediated through the action of tumor suppressor p53. In order to prevent the excessive loss of skin cells and to maintain the skin barrier function, apoptotic pathways are counteracted by anti-apoptotic signaling including the AKT/mTOR pathway. However, AKT/mTOR not only prevents cell death, but is also active in cell cycle transition and hyper-proliferation, thereby also counteracting p53. In turn, AKT/mTOR is tuned down by the negative regulators being controlled by the p53. This inhibition of AKT/mTOR, in combination with transactivation of damage-regulated autophagy modulators, guides the p53-mediated elimination of damaged cellular components by autophagic clearance. Alternatively, p53 irreversibly blocks cell cycle progression to prevent AKT/mTOR-driven proliferation, thereby inducing premature senescence. Conclusively, AKT/mTOR via an extensive cross talk with p53 influences the UV response in the skin with no black and white scenario deciding over death or survival.

  19. Tumor Necrosis Factor-α and Apoptosis Signal-Regulating Kinase 1 Control Reactive Oxygen Species Release, Mitochondrial Autophagy and C-Jun N-Terminal Kinase/P38 Phosphorylation During Necrotizing Enterocolitis

    Directory of Open Access Journals (Sweden)

    Naira Baregamian

    2009-01-01

    Full Text Available Background: Oxidative stress and inflammation may contribute to the disruption of the protective gut barrier through various mechanisms; mitochondrial dysfunction resulting from inflammatory and oxidative injury may potentially be a significant source of apoptosis during necrotizing enterocolitis (NEC. Tumor necrosis factor (TNFα is thought to generate reactive oxygen species (ROS and activate the apoptosis signal-regulating kinase 1 (ASK1-c-Jun N-terminal kinase (JNK/p38 pathway. Hence, the focus of our study was to examine the effects of TNFα/ROs on mitochondrial function, ASK1-JNK/p38 cascade activation in intestinal epithelial cells during NEC.

  20. Decoding c-Myc networks of cell cycle and apoptosis regulated genes in a transgenic mouse model of papillary lung adenocarcinomas.

    Science.gov (United States)

    Ciribilli, Yari; Singh, Prashant; Spanel, Reinhard; Inga, Alberto; Borlak, Jürgen

    2015-10-13

    The c-Myc gene codes for a basic-helix-loop-helix-leucine zipper transcription factor protein and is reported to be frequently over-expressed in human cancers. Given that c-Myc plays an essential role in neoplastic transformation we wished to define its activity in lung cancer and therefore studied its targeted expression to respiratory epithelium in a transgenic mouse disease model. Using histological well-defined tumors, transcriptome analysis identified novel c-Myc responsive cell cycle and apoptosis genes that were validated as direct c-Myc targets using EMSA, Western blotting, gene reporter and ChIP assays.Through computational analyses c-Myc cooperating transcription factors emerged for repressed and up-regulated genes in cancer samples, namely Klf7, Gata3, Sox18, p53 and Elf5 and Cebpα, respectively. Conversely, at promoters of genes regulated in transgenic but non-carcinomatous lung tissue enriched binding sites for c-Myc, Hbp1, Hif1 were observed. Bioinformatic analysis of tumor transcriptomic data revealed regulatory gene networks and highlighted mortalin and moesin as master regulators while gene reporter and ChIP assays in the H1299 lung cancer cell line as well as cross-examination of published ChIP-sequence data of 7 human and 2 mouse cell lines provided strong evidence for the identified genes to be c-Myc targets. The clinical significance of findings was established by evaluating expression of orthologous proteins in human lung cancer. Taken collectively, a molecular circuit for c-Myc-dependent cellular transformation was identified and the network analysis broadened the perspective for molecularly targeted therapies.

  1. Down-regulation of the nuclear factor-kappaB by lidamycin in association with inducing apoptosis in human pancreatic cancer cells and inhibiting xenograft growth.

    Science.gov (United States)

    Chen, Jing; Ouyang, Zhi-Gang; Zhang, Sheng-Hua; Zhen, Yong-Su

    2007-06-01

    Pancreatic cancer is now one of the most common causes of cancer death worldwide. K-ras mutations are present in up to 90% of pancreatic cancer cases. The expression of mutant K-ras activates the Akt/protein kinase B pathway, resulting in the activation of the nuclear factor-kappaB (NF-kappaB) transcriptional factor. Constitutive NF-kappaB activity plays a key role in pancreatic carcinoma. NF-kappaB has been shown to inhibit apoptosis in response to chemotherapeutic agents. In the present study, the effects of lidamycin (LDM), a member of the enediyne antibiotic family, were investigated on two established pancreatic cell lines, PANC-1 and SW1990. A dose-dependent inhibition of phospho-Akt and NF-kappaB activation was found in the cells treated with LDM as determined by Western blot analysis. Moreover, a down-regulation of K-ras mRNA and a protein expression by LDM were observed in both cell lines as determined by reverse transcription-PCR and Western blot analysis. By MTT assay, a remarkable difference in chemosensitivity to LDM, mitomycin, adriamycin, taxol, and gemcitabine was found in both cell lines. The IC50 values of LDM for the PANC-1 or SW1990 cells were 0.955+/-0.414 or 0.426+/-0.212 nM, respectively, lower than those of the other drugs. Growth inhibition, apoptosis induction and cell cycle arrest were observed in the LDM-treated cells. LDM decreased the invasive potential of pancreatic cancer cells by reducing matrix metalloproteinase-9 activity. Furthermore, LDM was found to suppress the growth of SW1990 xenografts in nude mice. Treatment with an i.v. injection of LDM at the dose of 0.02 and 0.04 mg/kg (once a week for two weeks) inhibited the growth of xenografts by 66 and 72%, respectively. By contrast, an i.p. injection of gemcitabine at the dose of 80 mg/kg inhibited the growth of xenografts by 38%. Our findings suggest that LDM is active in the down-regulation of NF-kappaB and could play a positive role in relevant targeted chemotherapy for

  2. 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

  3. Aspafilioside B induces G2/M cell cycle arrest and apoptosis by up-regulating H-Ras and N-Ras via ERK and p38 MAPK signaling pathways in human hepatoma HepG2 cells.

    Science.gov (United States)

    Liu, Wei; Ning, Rui; Chen, Rui-Ni; Huang, Xue-Feng; Dai, Qin-Sheng; Hu, Jin-Hua; Wang, Yu-Wen; Wu, Li-Li; Xiong, Jing; Hu, Gang; Guo, Qing-Long; Yang, Jian; Wang, Hao

    2016-05-01

    We recently establish that aspafilioside B, a steroidal saponin extracted from Asparagus filicinus, is an active cytotoxic component. However, its antitumor activity is till unknown. In this study, the anticancer effect of aspafilioside B against HCC cells and the underlying mechanisms were investigated. Our results showed that aspafilioside B inhibited the growth and proliferation of HCC cell lines. Further study revealed that aspafilioside B could significantly induce G2 phase cell cycle arrest and apoptosis, accompanying the accumulation of reactive oxygen species (ROS), but blocking ROS generation with N-acetyl-l-cysteine (NAC) could not prevent G2/M arrest and apoptosis. Additionally, treatment with aspafilioside B induced phosphorylation of extracellular signal-regulated kinase (ERK) and p38 MAP kinase. Moreover, both ERK inhibitor PD98059 and p38 inhibitor SB203580 almost abolished the G2/M phase arrest and apoptosis induced by aspafilioside B, and reversed the expression of cell cycle- and apoptosis-related proteins. We also found that aspafilioside B treatment increased both Ras and Raf activation, and transfection of cells with H-Ras and N-Ras shRNA almost attenuated aspafilioside B-induced G2 phase arrest and apoptosis as well as the ERK and p38 activation. Finally, in vivo, aspafilioside B suppressed tumor growth in mouse xenograft models, and the mechanism was the same as in vitro study. Collectively, these findings indicated that aspafilioside B may up-regulate H-Ras and N-Ras, causing c-Raf phosphorylation, and lead to ERK and p38 activation, which consequently induced the G2 phase arrest and apoptosis. This study provides the evidence that aspafilioside B is a promising therapeutic agent against HCC. PMID:25683703

  4. Synergistic efficacy of sorafenib and genistein in growth inhibition by down regulating angiogenic and survival factors and increasing apoptosis through upregulation of p53 and p21 in malignant neuroblastoma cells having N-Myc amplification or non-amplification.

    Science.gov (United States)

    Roy Choudhury, Subhasree; Karmakar, Surajit; Banik, Naren L; Ray, Swapan K

    2010-12-01

    Neuroblastoma is an extracranial, solid, and heterogeneous malignancy in children. The conventional therapeutic modalities are mostly ineffective and thus new therapeutic strategies for malignant neuroblastoma are urgently warranted. We examined the synergistic efficacy of combination of sorafenib (SF) and genistein (GST) in human malignant neuroblastoma SK-N-DZ (N-Myc amplified) and SH-SY5Y (N-Myc non-amplified) cell lines. MTT assay showed dose-dependent decrease in cell viability and the combination therapy more prominently inhibited the cell proliferation in both cell lines than either treatment alone. Apoptosis was confirmed morphologically by Wright staining. Flow cytometric analysis of cell cycle phase distribution and Annexin V-FITC/PI staining showed increase in subG1 DNA content and early apoptosis, respectively, after treatment with the combination of drugs. Apoptosis was further confirmed by scanning electron microscopy. Combination therapy showed activation of caspase-8, cleavage of Bid to tBid, increase in p53 and p21 expression, down regulation of anti-apoptotic Mcl-1, and increase in Bax:Bcl-2 ratio to trigger apoptosis. Down regulation of MDR, hTERT, N-Myc, VEGF, FGF-2, NF-κB, p-Akt, and c-IAP2 indicated suppression of angiogenic and survival pathways. Mitochondrial release of cytochrome c and Smac into cytosol indicated involvement of mitochondia in apoptosis. Increases in proteolytic activities of calpain and caspase-3 were also confirmed. Our results suggested that combination of SF and GST inhibited angiogenic and survival factors and increased apoptosis via receptor and mitochondria mediated pathways in both neuroblastoma SK-N-DZ and SH-SY5Y cell lines. Thus, this combination of drugs could be a potential therapeutic strategy against human malignant neuroblastoma cells having N-Myc amplification or non-amplification. PMID:19777160

  5. Regulation of the CD56 promoter and its association with proliferation, anti-apoptosis and clinical factors in multiple myeloma

    DEFF Research Database (Denmark)

    Damgaard, Tina; Knudsen, Lene M; Dahl, Inger Marie S;

    2009-01-01

    Multiple myeloma (MM) is an incurable B-cell malignancy characterised by uncontrolled growth and accumulation of malignant plasma cells in the bone marrow. Aberrant expression of CD56 in patients with MM is thought to contribute to a worsened disease course and metastasis. We therefore investigated...... the regulation of the CD56 promoter in relation to typical clinical factors. We used qPCR and FACS to measure the expression levels of CD56, and potential regulatory factors in patients with MM and related these with MM progression/prognosis. The transcription factors BTBD3, Pax5, RUNX1 and MMSET were positively...

  6. The Experimental and Clinical Study on the Effect of Curcumin on Cell Cycle Proteins and Regulating Proteins of Apoptosis in Acute Myelogenous Leukemia

    Institute of Scientific and Technical Information of China (English)

    陈燕; 吴裕丹; 何静; 陈文娟

    2002-01-01

    Summary: To investigate whether the Bcl-2 gene family is involved in modulating mechanism ofapoptosis and change of cell cycle protein induced by curcumin in acute myeloid leukemia HL-60cell line and primary acute myelogenous leukemic cells, the Bcl-2 family member Mcl-l, Bax andBak and cell cycle proteins including P27kipl, P21wafl, cyclin D3 and pRbp- were selected and their ex-pression detected by SABC immuno-histochemical stain method. The attitude of sub-G1 peak inDNA histogram was determined by FCM. The TUNEL positive cell percentage was identified byterminal deoxynucleotidyl transferase ( TdT )-mediated Biotin dUNP end labeling technique. Itwas found that when HL-60 cells were treated with 25 μmol/L curcumin for 24 h, the expressionlevel of Mcl-1 was down-regulated, but that of Bax and Bak up-regulated time-dependently. Therewas significant difference in the expression level of Mcl-1, Bax and Bak between the curcumin-treated groups and control group (P<0. 05-0. 01). At the same time, curcumin had no effect onprogress of cell cycle in primaty acute myelogenous leukemia at newly diagnosis, but could in-crease the peak of Sub-G1 (P<0. 05), and down-regulate the expression of Mcl-1 and up-regulatethe expression of Bax and Bak with the difference being statistically significant. The expression ofP27kipl, P21wafl and pRbp- were elevated and that of cyclin D3 decreased in the presence of curcumin.These findings suggested that the Bcl-2 gene family indeed participated in the regulatory process ofapoptosisinduced by curcumin in HL-60 cells and AML cells. Curcumin can induce apoptosis ofprimary acute myelogenous leukemic cells and disturb cell cycle progression of HL-60 cells. Themechanism appeared to be mediated by perturbing Go/G1 phases checkpoints which associated withup-regulation of P27kipl, P21wafl and pRbp- expression, and down-regulation of cyclin D3.

  7. Proteasome inhibition-induced p38 MAPK/ERK signaling regulates autophagy and apoptosis through the dual phosphorylation of glycogen synthase kinase 3{beta}

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Cheol-Hee [Research Center for Resistant Cells, Chosun University, Seosuk-dong, Dong-gu, Gwangju 501-759 (Korea, Republic of); Department of Pharmacology, College of Medicine, Chosun University, Seosuk-dong, Dong-gu, Gwangju 501-759 (Korea, Republic of); Lee, Byung-Hoon [College of Pharmacy and Multiscreening Center for Drug Development, Seoul National University, Seoul 151-742 (Korea, Republic of); Ahn, Sang-Gun [Department of Pathology, College of Dentistry, Chosun University, Gwangju 501-759 (Korea, Republic of); Oh, Seon-Hee, E-mail: oshccw@hanmail.net [Research Center for Resistant Cells, Chosun University, Seosuk-dong, Dong-gu, Gwangju 501-759 (Korea, Republic of)

    2012-02-24

    Highlights: Black-Right-Pointing-Pointer MG132 induces the phosphorylation of GSK3{beta}{sup Ser9} and, to a lesser extent, of GSK3{beta}{sup Thr390}. Black-Right-Pointing-Pointer MG132 induces dephosphorylation of p70S6K{sup Thr389} and phosphorylation of p70S6K{sup Thr421/Ser424}. Black-Right-Pointing-Pointer Inactivation of p38 dephosphorylates GSK3{beta}{sup Ser9} and phosphorylates GSK3{beta}{sup Thr390}. Black-Right-Pointing-Pointer Inactivation of p38 phosphorylates p70S6K{sup Thr389} and increases the phosphorylation of p70S6K{sup Thr421/Ser424}. Black-Right-Pointing-Pointer Inactivation of p38 decreases autophagy and increases apoptosis induced by MG132. -- Abstract: Proteasome inhibition is a promising approach for cancer treatment; however, the underlying mechanisms involved have not been fully elucidated. Here, we show that proteasome inhibition-induced p38 mitogen-activated protein kinase regulates autophagy and apoptosis by modulating the phosphorylation status of glycogen synthase kinase 3{beta} (GSK3{beta}) and 70 kDa ribosomal S6 kinase (p70S6K). The treatment of MDA-MB-231 cells with MG132 induced endoplasmic reticulum stress through the induction of ATF6a, PERK phosphorylation, and CHOP, and apoptosis through the cleavage of Bax and procaspase-3. MG132 caused the phosphorylation of GSK3{beta} at Ser{sup 9} and, to a lesser extent, Thr{sup 390}, the dephosphorylation of p70S6K at Thr{sup 389}, and the phosphorylation of p70S6K at Thr{sup 421} and Ser{sup 424}. The specific p38 inhibitor SB203080 reduced the p-GSK3{beta}{sup Ser9} and autophagy through the phosphorylation of p70S6K{sup Thr389}; however, it augmented the levels of p-ERK, p-GSK3{beta}{sup Thr390}, and p-70S6K{sup Thr421/Ser424} induced by MG132, and increased apoptotic cell death. The GSK inhibitor SB216763, but not lithium, inhibited the MG132-induced phosphorylation of p38, and the downstream signaling pathway was consistent with that in SB203580-treated cells. Taken together, our

  8. Human cytomegalovirus-encoded miR-US4-1 promotes cell apoptosis and benefits discharge of infectious virus particles via down-regulation of glutaminyl-tRNA synthetase, QARS in HCMV-infected HELF cells

    Indian Academy of Sciences (India)

    Yaozhong Shao; Ying Qi; Yujing Huang; Zhongyang Liu; Yanping Ma; Xin Guo; Shujuan Jiang; Zhengrong Sun; Qiang Ruan

    2016-06-01

    Human cytomegalovirus (HCMV) can cause congenital diseases and opportunistic infections in immunocompromised individuals. Its functional proteins and microRNAs (miRNAs) facilitate efficient viral propagation by altering host cell behaviour. Identification of functional target genes of miRNAs is an important step in studies on HCMV pathogenesis. In this study, Glutaminyl-tRNA Synthetase (QARS), which could regulate signal transduction pathways for cellular apoptosis, was identified as a direct target of hcmv-miR-US4-1. Apoptosis assay revealed that as silence of QARS by ectopic expression of hcmv-miR-US4-1 and specific small interference RNA of QARS can promote cell apoptosis in HCMV-infected HELF cells. Moreover, viral growth curve assays showed that hcmv-miR-US4-1 benefits the discharge of infectious virus particles. However, silence of hcmv-miR-US4-1 by its specific inhibitor overturned these effects. These results imply that hcmv-miR-US4-1 might have the same effects during HCMV nature infection. In general, hcmv-miR-US4-1 may involve in promoting cell apoptosis and benefiting discharge of infectious virus particles via down-regulation of QARS in HCMV-infected HELF cells.

  9. Data on the transcriptional regulation of DNA damage induced apoptosis suppressor (DDIAS) by ERK5/MEF2B pathway in lung cancer cells.

    Science.gov (United States)

    Im, Joo-Young; Yoon, Sung-Hoon; Kim, Bo-Kyung; Ban, Hyun Seung; Won, Kyoung-Jae; Chung, Kyung-Sook; Jung, Kyeong Eun; Won, Misun

    2016-12-01

    The data included in this article are associated with the article entitled "DNA-damage-induced apoptosis suppressor (DDIAS) is upregulated via ERK5/MEF2B signaling and promotes β-catenin-mediated invasion" (J.Y. Im, S.H. Yoon, B.K. Kim, H.S. Ban, K.J. Won, K.S. Chung, K.E. Jung, M. Won) [1]. Quantitative RT-PCR data revealed that genetic or pharmacological inhibition of extracellular signal-regulated kinase 5 (ERK5) suppresses DDIAS transcription in response to epidermal growth factor (EGF) in Hela cells. p300 did not interact with myocyte enhancer factor 2B (MEF2B), a downstream target of ERK5 and affect transcription of DDIAS. Moreover, DDIAS transcription is activated by ERK5/MEF2B signaling on EGF exposure in the non-small cell lung cancer cells (NSCLC) NCI-H1703 and NCI-H1299. DDIAS knockdown suppresses lung cancer cell invasion by decreasing β-catenin protein level on EGF exposure. PMID:27660814

  10. Increase of RhoB in {gamma}-radiation-induced apoptosis is regulated by c-Jun N-terminal kinase in Jurkat T cells

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Chun-Ho [Laboratory of Cytogenetics and Tissue Regeneration, KIRAMS, Seoul 139-706 (Korea, Republic of); Won, Misun; Choi, Chung-Hae; Ahn, Jiwon; Kim, Bo-Kyung [Genome Research Center, KRIBB, Daejeon 305-806 (Korea, Republic of); Song, Kyung-Bin [Department of Food Science and Technology, Chungnam National University, Daejeon 305-764 (Korea, Republic of); Kang, Chang-Mo, E-mail: kangcm@kcch.re.kr [Laboratory of Cytogenetics and Tissue Regeneration, KIRAMS, Seoul 139-706 (Korea, Republic of); Chung, Kyung-Sook, E-mail: kschung@kribb.re.kr [Genome Research Center, KRIBB, Daejeon 305-806 (Korea, Republic of)

    2010-01-08

    The Ras-related small GTP-binding protein RhoB is known to be a pro-apoptotic protein and immediate-early inducible by genotoxic stresses. In addition, JNK activation is known to function in {gamma}-radiation-induced apoptosis. However, it is unclear how JNK activation and {gamma}-radiation-dependent RhoB induction are related. Here we verified the relationship between JNK activation and RhoB induction. RhoB induction by {gamma}-radiation occurred at the transcriptional level and transcriptional activation of RhoB was concomitant with an increase in RhoB protein. {gamma}-Radiation-induced RhoB expression was markedly attenuated by pretreatment with a JNK-specific inhibitor, SP600125, but not by a p38 MAPK inhibitor, SB203580. Inhibition of JNK caused a decrease in early apoptotic cell death that correlated with RhoB expression. However, PI3K inhibition had no significant effects, indicating that the AKT survival pathway was not involved. The siRNA knockdown of JNK resulted in a decrease in RhoB expression and the siRNA knockdown of RhoB restored cell growth even in the {gamma}-irradiated cells. These results suggest that RhoB regulation involves the JNK pathway and contributes to the early apoptotic response of Jurkat T cells to {gamma}-radiation.

  11. Farnesiferol c induces apoptosis via regulation of L11 and c-Myc with combinational potential with anticancer drugs in non-small-cell lung cancers.

    Science.gov (United States)

    Jung, Ji Hoon; Kim, Moon Joon; Lee, Hyemin; Lee, Jihyun; Kim, Jaekwang; Lee, Hyun Joo; Shin, Eun Ah; Kim, Yoon Hyeon; Kim, Bonglee; Shim, Bum Sang; Kim, Sung-Hoon

    2016-01-01

    Though Farnesiferol c (FC) has been reported to have anti-angiogenic and antitumor activity, the underlying antitumor mechanism of FC still remains unclear. Thus, in the present study, we investigated the apoptotic mechanism of FC in human H1299 and H596 non-small lung cancer cells (NSCLCs). FC significantly showed cytotoxicity, increased sub-G1 accumulation, and attenuated the expression of Bcl-2, Bcl-xL, Survivin and procaspase 3 in H1299 and H596 cells. Furthermore, FC effectively suppressed the mRNA expression of G1 arrest related genes such as Cyclin D1, E2F1 transcription factor and CDC25A by RT-PCR. Interestingly, FC inhibited the expression of c-Myc, ribosomal protein L11 (L11) and nucleolin (NCL) in H1299 and H596 cells. Of note, silencing of L11 by siRNA transfection enhanced the expression of c-Myc through a negative feedback mechanism, while c-Myc knockdown downregulated L11 in H1299 cells. Additionally, combined treatment of FC and puromycin/doxorubicin promoted the activation of caspase 9/3, and attenuated the expression of c-Myc, Cyclin D1 and CDK4 in H1299 cells compared to single treatment. Taken together, our findings suggest that FC induces apoptosis and G1 arrest via regulation of ribosomal protein L11 and c-Myc and also enhances antitumor effect of puromycin or doxorubicin in NSCLCs. PMID:27231235

  12. Activation of PPARδ up-regulates fatty acid oxidation and energy uncoupling genes of mitochondria and reduces palmitate-induced apoptosis in pancreatic β-cells

    International Nuclear Information System (INIS)

    Recent evidence indicates that decreased oxidative capacity, lipotoxicity, and mitochondrial aberrations contribute to the development of insulin resistance and type 2 diabetes. The goal of this study was to investigate the effects of peroxisome proliferator-activated receptor δ (PPARδ) activation on lipid oxidation, mitochondrial function, and insulin secretion in pancreatic β-cells. After HIT-T15 cells (a β-cell line) were exposed to high concentrations of palmitate and GW501516 (GW; a selective agonist of PPARδ), we found that administration of GW increased the expression of PPARδ mRNA. GW-induced activation of PPARδ up-regulated carnitine palmitoyltransferase 1 (CPT1), long-chain acyl-CoA dehydrogenase (LCAD), pyruvate dehydrogenase kinase 4 (PDK4), and uncoupling protein 2 (UCP2); alleviated mitochondrial swelling; attenuated apoptosis; and reduced basal insulin secretion induced by increased palmitate in HIT cells. These results suggest that activation of PPARδ plays an important role in protecting pancreatic β-cells against aberrations caused by lipotoxicity in metabolic syndrome and diabetes.

  13. Activation of PPAR{delta} up-regulates fatty acid oxidation and energy uncoupling genes of mitochondria and reduces palmitate-induced apoptosis in pancreatic {beta}-cells

    Energy Technology Data Exchange (ETDEWEB)

    Wan, Jun; Jiang, Li; Lue, Qingguo; Ke, Linqiu [Department of Endocrinology, West China Hospital of Sichuan University, 37 Guoxue Lane, Chengdu, Sichuan 610041 (China); Li, Xiaoyu [State Key Laboratory of Oral Diseases, Sichuan University, No. 14, 3rd Section, Renmin South Road, Chengdu, Sichuan 610041 (China); Tong, Nanwei, E-mail: buddyjun@hotmail.com [Department of Endocrinology, West China Hospital of Sichuan University, 37 Guoxue Lane, Chengdu, Sichuan 610041 (China)

    2010-01-15

    Recent evidence indicates that decreased oxidative capacity, lipotoxicity, and mitochondrial aberrations contribute to the development of insulin resistance and type 2 diabetes. The goal of this study was to investigate the effects of peroxisome proliferator-activated receptor {delta} (PPAR{delta}) activation on lipid oxidation, mitochondrial function, and insulin secretion in pancreatic {beta}-cells. After HIT-T15 cells (a {beta}-cell line) were exposed to high concentrations of palmitate and GW501516 (GW; a selective agonist of PPAR{delta}), we found that administration of GW increased the expression of PPAR{delta} mRNA. GW-induced activation of PPAR{delta} up-regulated carnitine palmitoyltransferase 1 (CPT1), long-chain acyl-CoA dehydrogenase (LCAD), pyruvate dehydrogenase kinase 4 (PDK4), and uncoupling protein 2 (UCP2); alleviated mitochondrial swelling; attenuated apoptosis; and reduced basal insulin secretion induced by increased palmitate in HIT cells. These results suggest that activation of PPAR{delta} plays an important role in protecting pancreatic {beta}-cells against aberrations caused by lipotoxicity in metabolic syndrome and diabetes.

  14. The Fruits of Wampee Inhibit H2O2-Induced Apoptosis in PC12 Cells via the NF-κB Pathway and Regulation of Cellular Redox Status

    Directory of Open Access Journals (Sweden)

    Xiaobin Zeng

    2014-06-01

    Full Text Available Wampee (Clausena lansium fruits (CLS, whose pulp can be used to prepare fruit cups, desserts, jam, or jelly, can be eaten along with the peel. In this study, a PC12 cell model was built to observe the protective effect of CLS against H2O2-induced oxidative stress. We found that pretreatment with CLS increased cell viability and inhibited cytotoxicity, caspase-3 activity and DNA condensation. CLS also attenuated the increase in ROS production and MMP reduction. Moreover, we attempted to determine whether CLS suppressed the expression and phosphorylation of NF-κB. Western blot and immunostaining assay revealed that CLS inhibited H2O2-induced up-regulation of NF-κB p65 and pNF-κB p65. And CLS significantly suppressed the translocation of NF-κB p65 and pNF-κB p65 from cytoplasm to nuclear. Also, seven major compounds including a new flavanoid, luteolin-4'-O-β-d-gluco-pyranoside (3 and six known compounds 1,2, 4–7 were isolated and identified from CLS. Their antioxidative and H2O2-induced PC12 cell apoptosis-reversing activity were determined. These findings suggest that CLS and its major constituents (flavanoids may be potential antioxidant agents and should encourage further research into their use as a functional food for neurodegenerative diseases.

  15. Genetic Networks Lead and Follow Tumor Development: MicroRNA Regulation of Cell Cycle and Apoptosis in the p53 Pathways

    Directory of Open Access Journals (Sweden)

    Kurataka Otsuka

    2014-01-01

    Full Text Available During the past ten years, microRNAs (miRNAs have been shown to play a more significant role in the formation and progression of cancer diseases than previously thought. With an increase in reports about the dysregulation of miRNAs in diverse tumor types, it becomes more obvious that classic tumor-suppressive molecules enter deep into the world of miRNAs. Recently, it has been demonstrated that a typical tumor suppressor p53, known as the guardian of the genome, regulates some kinds of miRNAs to contribute to tumor suppression by the induction of cell-cycle arrest and apoptosis. Meanwhile, miRNAs directly/indirectly control the expression level and activity of p53 to fine-tune its functions or to render p53 inactive, indicating that the interplay between p53 and miRNA is overly complicated. The findings, along with current studies, will underline the continuing importance of understanding this interlocking control system for future therapeutic strategies in cancer treatment and prevention.

  16. The Impact of Adenosine Fast Induction of Myocardial Arrest during CABG on Myocardial Expression of Apoptosis-Regulating Genes Bax and Bcl-2

    Directory of Open Access Journals (Sweden)

    Ahmed Shalaby

    2009-01-01

    Full Text Available Background. We studied the effect of fast induction of cardiac arrest with denosine on myocardial bax and bcl-2 expression. Methods and Results. 40 elective CABG patients were allocated into two groups. The adenosine group (n=20 received 250 μg/kg adenosine into the aortic root followed by blood potassium cardioplegia. The control group received potassium cardioplegia in blood. Bcl-2 and bax were measured. Bax was reduced in the postoperative biopsies (1.38 versus 0.47, P=.002 in the control group. Bcl-2 showed a reducing tendency (0.14 versus 0.085, P=.07. After the adenosine treatment, the expression of both bax (0.52 versus 0.59, P=.4 and bcl-2 (0.104 versus 0.107, P=.4 remained unaltered after the operation. Conclusion. Open heart surgery is associated with rapid reduction in the expression of apoptosis regulating genes bax and bcl-2. Fast Adenosine induction abolished changes in their expression.

  17. Resolvin D1 Protects Lipopolysaccharide-induced Acute Kidney Injury by Down-regulating Nuclear Factor-kappa B Signal and Inhibiting Apoptosis

    Institute of Scientific and Technical Information of China (English)

    Yu-Liang Zhao; Ling Zhang; Ying-Ying Yang; Yi Tang; Jiao-Jiao Zhou; Yu-Ying Feng; Tian-Lei Cui

    2016-01-01

    stimulation,the mRNA expression of toll-like receptor 4,myeloid differentiation factor 88,and TNF-α in both mice kidneys and HK-2 cells were all up-regulated,while RvD1 substantially inhibited the up-regulation of these genes.Western blotting showed that the phosphorylated-IκB/IκB ratio in LPS group was significantly higher than that in the control group,which was inhibited in the RvD1 group.RvD1 could inhibit the up-regulation of cleaved-caspase-3 protein stimulated by LPS,which was prohibited in RvD1 blockage group.RvD1 group also had a lower proportion of apoptotic nuclei in mice kidney by TUNEL staining compared with LPS group.Conclusion:In LPS-induced AKI,RvD1 could decrease TNF-α level,ameliorate kidney pathological injury,protect kidney function,and improve animal survival by down-regulating NF-κB inflammatory signal as well as inhibiting renal cell apoptosis.

  18. Molecular signal transduction in vascular cell apoptosis

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Apoptosis is a form of genetically programmed cell death, which plays a key role in regulation of cellularity in a variety of tissue and cell types including the cardiovascular tissues. Under both physiological and pathophysiological conditions, various biophysiological and biochemical factors, including mechanical forces, reactive oxygen and nitrogen species, cytokines, growth factors, oxidized lipoproteins, etc., may influence apoptosis of vascular cells. The Fas/Fas ligand/caspase death-signaling pathway, Bcl-2 protein family/mitochondria, the tumor suppressive gene p53, and the proto-oncogene c-myc may be activated in atherosclerotic lesions, and mediates vascular apoptosis during the development of atherosclerosis. Abnormal expression and dysfunction of these apoptosis-regulating genes may attenuate or accelerate vascular cell apoptosis and affect the integrity and stability of atherosclerotic plaques. Clarification of the molecular mechanism that regulates apoptosis may help design a new strategy for treatment of atherosclerosis and its major complication, the acute vascular syndromes.

  19. MiR-27a targets sFRP1 in hFOB cells to regulate proliferation, apoptosis and differentiation.

    Directory of Open Access Journals (Sweden)

    Donggeng Guo

    Full Text Available MicroRNAs (miRNAs play a key role in the regulation of almost all the physiological and pathological processes, including bone metabolism. Recent studies have suggested that miR-27 might play a key role in osteoblast differentiation and bone formation. Increasing evidence indicates that the canonical Wnt signaling pathway contributes to different stages of bone formation. In this study, we identify miR-27a can promote osteoblast differentiation by repressing a new target, secreted frizzled-related proteins 1 (sFRP1 expression at the transcriptional level. Here, 21 candidate targets of miR-27a involved in canonical Wnt/β-catenin signaling were predicted, and a significant decrease in sFRP1 luciferase activity was observed both in 293T and MG63 cells co-transfected with the matched luciferase reporter constructs and miR-27a mimic. Furthermore, the presence of exogenous miR-27a significantly decreased sFRP1 mRNA and protein expression in hFOB1.19 cells during both proliferation and osteogenic differentiation. The over-expression of miR-27a or knockdown sFRP1 significantly increased the percentage of apoptotic hFOBs, the percentage of cells in the G2-M phase of the cell cycle and the expression of key osteoblastic markers, including ALP, SPP1, RUNX2 and ALP activity. Over-expression of miR-27a or knockdown of endogenous sFRP1 led to an accumulation of β-catenin in hFOBs. In the present study, we demonstrate that miR-27a induced gene silencing effect is a vital mechanism contributing to bone metabolism in hFOB cells in vitro, which is partly affected by the post-transcriptional regulation of sFRP1, during osteoblast proliferation, apoptosis and differentiation.

  20. Differential splicing of the apoptosis-associated speck like protein containing a caspase recruitment domain (ASC regulates inflammasomes

    Directory of Open Access Journals (Sweden)

    Rojanasakul Yon

    2010-05-01

    Full Text Available Abstract Background The apoptotic speck-like protein containing a caspase recruitment domain (ASC is the essential adaptor protein for caspase 1 mediated interleukin (IL-1β and IL-18 processing in inflammasomes. It bridges activated Nod like receptors (NLRs, which are a family of cytosolic pattern recognition receptors of the innate immune system, with caspase 1, resulting in caspase 1 activation and subsequent processing of caspase 1 substrates. Hence, macrophages from ASC deficient mice are impaired in their ability to produce bioactive IL-1β. Furthermore, we recently showed that ASC translocates from the nucleus to the cytosol in response to inflammatory stimulation in order to promote an inflammasome response, which triggers IL-1β processing and secretion. However, the precise regulation of inflammasomes at the level of ASC is still not completely understood. In this study we identified and characterized three novel ASC isoforms for their ability to function as an inflammasome adaptor. Methods To establish the ability of ASC and ASC isoforms as functional inflammasome adaptors, IL-1β processing and secretion was investigated by ELISA in inflammasome reconstitution assays, stable expression in THP-1 and J774A1 cells, and by restoring the lack of endogenous ASC in mouse RAW264.7 macrophages. In addition, the localization of ASC and ASC isoforms was determined by immunofluorescence staining. Results The three novel ASC isoforms, ASC-b, ASC-c and ASC-d display unique and distinct capabilities to each other and to full length ASC in respect to their function as an inflammasome adaptor, with one of the isoforms even showing an inhibitory effect. Consistently, only the activating isoforms of ASC, ASC and ASC-b, co-localized with NLRP3 and caspase 1, while the inhibitory isoform ASC-c, co-localized only with caspase 1, but not with NLRP3. ASC-d did not co-localize with NLRP3 or with caspase 1 and consistently lacked the ability to function as an

  1. Ginkgo biloba extract mitigates liver fibrosis and apoptosis by regulating p38 MAPK, NF-κB/IκBα, and Bcl-2/Bax signaling

    Directory of Open Access Journals (Sweden)

    Wang YY

    2015-12-01

    Full Text Available Yuanyuan Wang, Rong Wang, Yujie Wang, Ruqin Peng, Yan Wu, Yongfang Yuan Department of Pharmacy, Shanghai 9th People’s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, People’s Republic of China Background: Liver fibrosis is the consequence of diverse liver injuries and can eventually develop into liver cirrhosis. Ginkgo biloba extract (GBE is an extract from dried ginkgo leaves that has many pharmacological effects because of its various ingredients and has been shown to be hepatoprotective. Purpose and methods: Aimed to investigate the underlying protective mechanisms of GBE on carbon tetrachloride (CCl4-induced liver fibrosis in rats. Male Sprague Dawley rats were randomly divided into four groups: control group (C, model group (M, low-dose group (L, and high-dose group (H. Liver fibrosis was induced by CCl4 groups M, L, and H: group C was administered saline. In addition, GBE at different doses was used to treat groups L and H. Results: The results of hematoxylin and eosin staining, Masson’s trichrome staining, a liver function index, and a liver fibrosis index showed that GBE application noticeably mitigated fibrosis and improved the function of the liver. The western blotting and immunohistochemistry analyses indicated that GBE reduced liver fibrosis not only by inhibiting p38 MAPK and NF-κBp65 via inhibition of IκBα degradation but also by inhibiting hepatocyte apoptosis via downregulation of Bax, upregulation of Bcl-2, and subsequent inhibition of caspase-3 activation. Inflammation-associated factors and hepatic stellate cell (HSC-activation markers further demonstrated that GBE could effectively inhibit HSC activation and inflammation as a result of its regulation of p38 MAPK and nuclear factor-kappa B/IκBα signaling. Conclusion: Our findings indicated a novel role for GBE in the treatment of liver fibrosis. The potential mechanisms may be associated with the following signaling pathways: 1 the p38 MAPK

  2. Analysis of expression, cellular localization, and function of three inhibitors of apoptosis (IAPs from Litopenaeus vannamei during WSSV infection and in regulation of antimicrobial peptide genes (AMPs.

    Directory of Open Access Journals (Sweden)

    Pei-Hui Wang

    Full Text Available Inhibitors of apoptosis (IAPs play important roles in apoptosis and NF-κB activation. In this study, we cloned and characterized three IAPs (LvIAP1-3 from the Pacific white shrimp, Litopenaeusvannamei. LvIAP1-3 proteins shared signature domains and exhibited significant similarities with other IAP family proteins. The tissue distributions of LvIAP1-3 were studied. The expression of LvIAP1-3 was induced in the muscle after white spot syndrome virus (WSSV infection. LvIAP1 expression in the gill, hemocytes, hepatopancreas, and intestine was responsive to WSSV and Vibrioalginolyticus infections. LvIAP2 expression in the gill, hemocytes, and hepatopancreas was also responsive to WSSV infection. The expression of LvIAP3 in the gill, hemocytes, and intestine was reduced after V. alginolyticus infection. When overexpressed in Drosophila S2 cells, GFP labeled-LvIAP2 was distributed in the cytoplasm and appeared as speck-like aggregates in the nucleus. Both LvIAP1 and LvIAP3 were widely distributed throughout the cytoplasm and nucleus. The expression of LvIAP1, LvIAP2, and LvIAP3 was significantly knocked down by dsRNA-mediated gene silencing. In the gill of LvIAP1- or LvIAP3-silenced shrimp, the expression of WSSV VP28 was significantly higher than that of the dsGFP control group, suggesting that LvIAP1 and LvIAP3 may play protective roles in host defense against WSSV infection. Intriguingly, the LvIAP2-silenced shrimp all died within 48 hours after dsLvIAP2 injection. In the hemocytes of LvIAP2-silenced shrimps, the expression of antimicrobial peptide genes (AMPs, including Penaeidins, lysozyme, crustins, Vibriopenaeicidae-induced cysteine and proline-rich peptides (VICPs, was significantly downregulated, while the expression of anti-lipopolysaccharide factors (ALFs was upregulated. Moreover, LvIAP2 activated the promoters of the NF-κB pathway-controlled AMPs, such as shrimp Penaeidins and Drosophila drosomycin and attacin A, in Drosophila S2 cells

  3. Ruthenium Complexes Induce HepG2 Human Hepatocellular Carcinoma Cell Apoptosis and Inhibit Cell Migration and Invasion through Regulation of the Nrf2 Pathway

    Directory of Open Access Journals (Sweden)

    Yiyu Lu

    2016-05-01

    Full Text Available Ruthenium (Ru complexes are currently the focus of substantial interest because of their potential application as chemotherapeutic agents with broad anticancer activities. This study investigated the in vitro and in vivo anticancer activities and mechanisms of two Ru complexes—2,3,7,8,12,13,17,18-Octaethyl-21H,23H-porphine Ru(II carbonyl (Ru1 and 5,10,15,20-Tetraphenyl-21H,23H-porphine Ru(II carbonyl (Ru2—against human hepatocellular carcinoma (HCC cells. These Ru complexes effectively inhibited the cellular growth of three human hepatocellular carcinoma (HCC cells, with IC50 values ranging from 2.7–7.3 μM. In contrast, the complexes exhibited lower toxicity towards L02 human liver normal cells with IC50 values of 20.4 and 24.8 μM, respectively. Moreover, Ru2 significantly inhibited HepG2 cell migration and invasion, and these effects were dose-dependent. The mechanistic studies demonstrated that Ru2 induced HCC cell apoptosis, as evidenced by DNA fragmentation and nuclear condensation, which was predominately triggered via caspase family member activation. Furthermore, HCC cell treatment significantly decreased the expression levels of Nrf2 and its downstream effectors, NAD(PH: quinone oxidoreductase 1 (NQO1 and heme oxygenase 1 (HO1. Ru2 also exhibited potent in vivo anticancer efficacy in a tumor-bearing nude mouse model, as demonstrated by a time- and dose-dependent inhibition on tumor growth. The results demonstrate the therapeutic potential of Ru complexes against HCC via Nrf2 pathway regulation.

  4. Ruthenium Complexes Induce HepG2 Human Hepatocellular Carcinoma Cell Apoptosis and Inhibit Cell Migration and Invasion through Regulation of the Nrf2 Pathway

    Science.gov (United States)

    Lu, Yiyu; Shen, Ting; Yang, Hua; Gu, Weiguang

    2016-01-01

    Ruthenium (Ru) complexes are currently the focus of substantial interest because of their potential application as chemotherapeutic agents with broad anticancer activities. This study investigated the in vitro and in vivo anticancer activities and mechanisms of two Ru complexes—2,3,7,8,12,13,17,18-Octaethyl-21H,23H-porphine Ru(II) carbonyl (Ru1) and 5,10,15,20-Tetraphenyl-21H,23H-porphine Ru(II) carbonyl (Ru2)—against human hepatocellular carcinoma (HCC) cells. These Ru complexes effectively inhibited the cellular growth of three human hepatocellular carcinoma (HCC) cells, with IC50 values ranging from 2.7–7.3 μM. In contrast, the complexes exhibited lower toxicity towards L02 human liver normal cells with IC50 values of 20.4 and 24.8 μM, respectively. Moreover, Ru2 significantly inhibited HepG2 cell migration and invasion, and these effects were dose-dependent. The mechanistic studies demonstrated that Ru2 induced HCC cell apoptosis, as evidenced by DNA fragmentation and nuclear condensation, which was predominately triggered via caspase family member activation. Furthermore, HCC cell treatment significantly decreased the expression levels of Nrf2 and its downstream effectors, NAD(P)H: quinone oxidoreductase 1 (NQO1) and heme oxygenase 1 (HO1). Ru2 also exhibited potent in vivo anticancer efficacy in a tumor-bearing nude mouse model, as demonstrated by a time- and dose-dependent inhibition on tumor growth. The results demonstrate the therapeutic potential of Ru complexes against HCC via Nrf2 pathway regulation. PMID:27213353

  5. Fluoxetine up-regulates expression of cellular FLICE-inhibitory protein and inhibits LPS-induced apoptosis in hippocampus-derived neural stem cell

    International Nuclear Information System (INIS)

    Fluoxetine is a widely used antidepressant compound which inhibits the reuptake of serotonin in the central nervous system. Recent studies have shown that fluoxetine can promote neurogenesis and improve the survival rate of neurons. However, whether fluoxetine modulates the proliferation or neuroprotection effects of neural stem cells (NSCs) needs to be elucidated. In this study, we demonstrated that 20 μM fluoxetine can increase the cell proliferation of NSCs derived from the hippocampus of adult rats by MTT test. The up-regulated expression of Bcl-2, Bcl-xL and the cellular FLICE-inhibitory protein (c-FLIP) in fluoxetine-treated NSCs was detected by real-time RT-PCR. Our results further showed that fluoxetine protects the lipopolysaccharide-induced apoptosis in NSCs, in part, by activating the expression of c-FLIP. Moreover, c-FLIP induction by fluoxetine requires the activation of the c-FLIP promoter region spanning nucleotides -414 to -133, including CREB and SP1 sites. This effect appeared to involve the phosphatidylinositol-3-kinase-dependent pathway. Furthermore, fluoxetine treatment significantly inhibited the induction of proinflammatory factor IL-1β, IL-6, and TNF-α in the culture medium of LPS-treated NSCs (p < 0.01). The results of high performance liquid chromatography coupled to electrochemical detection further confirmed that fluoxentine increased the functional production of serotonin in NSCs. Together, these data demonstrate the specific activation of c-FLIP by fluoxetine and indicate the novel role of fluoxetine for neuroprotection in the treatment of depression

  6. Effects of Zuogui Wan on neurocyte apoptosis and down-regulation of TGF-β1 expression in nuclei of arcuate hypothalamus of monosodium glutamate -liver regeneration rats

    Institute of Scientific and Technical Information of China (English)

    Han-Min Li; Xiang Gao; Mu-Lan Yang; Jia-Jun Mei; Liu-Tong Zhang; Xing-Fan Qiu

    2004-01-01

    AIM: To inquire into the effects and mechanism of Zuogui Wan (Pills for Kidney Yin) on neurocyte apoptosis in nuclei of arcuate hypothalamus (ARN) of monosodium glutamate(MSG)-liver regeneration rats, and the mechanism of liver regeneration by using optic microscope, electron microscope and in situ end labeling technology to adjust nerve-endocrineimmunity network.METHODS: Neurocyte apoptosis in ARN of the experiment rats was observed by using optic microscope, electron microscope andin situ end labeling technology. Expression of TGF-β1 in ARN was observed by using immunohistochemistry method.RESULTS: The expression of TGF-β1 in rats of model group was increased with the increase of ARN neurocyte apoptosis index (AI) (t = 8.3097, 12.9884, P<0.01). As compared with the rats of model group, the expression of TGF-β1 in rats of Zuogui Wan treatment group was decreased with the significant decrease of ARN neurocyte apoptosis (t = 4.5624,11.1420, P<0.01).CONCLUSION: Brain neurocyte calcium ion overexertion and TGF-β1 protein participate in the adjustment and control of ARN neurocyte apoptosis in MSG-liver regeneration-rats. Zuogui Wan can prevent ARN neurocyte apoptosis of MSG-liver regeneration in rats by downregulating the expression of TGF-β1, and influence liver regeneration through adjusting nerve-endocrine-immune network.

  7. Fullerene and apoptosis

    Directory of Open Access Journals (Sweden)

    M. A. Orlova

    2013-01-01

    Full Text Available Fullerene derivatives superfamily attracts a serious attention as antiviral and anticancer agents and drug delivery carriers as well. A large number of such fullerene С60 derivatives obtained to date. However, there is an obvious deficit of information about causes and mechanisms of immediately and long-term consequences of their effects in vivo which is a true obstacle on the way leading to practical medical use of them. First, this concerns their impact on the proliferation, apoptosis and necrosis regulation. Fullerene nanoparticle functionalization type, their sizes and surface nanopathology are of great importance to further promoting of either cytoprotective or cytotoxic effects. This lecture provides modern concept analysis regarding fullerenes effects on apoptosis pathway in normal and tumor cells.

  8. Fullerene and apoptosis

    Directory of Open Access Journals (Sweden)

    M. A. Orlova

    2014-07-01

    Full Text Available Fullerene derivatives superfamily attracts a serious attention as antiviral and anticancer agents and drug delivery carriers as well. A large number of such fullerene С60 derivatives obtained to date. However, there is an obvious deficit of information about causes and mechanisms of immediately and long-term consequences of their effects in vivo which is a true obstacle on the way leading to practical medical use of them. First, this concerns their impact on the proliferation, apoptosis and necrosis regulation. Fullerene nanoparticle functionalization type, their sizes and surface nanopathology are of great importance to further promoting of either cytoprotective or cytotoxic effects. This lecture provides modern concept analysis regarding fullerenes effects on apoptosis pathway in normal and tumor cells.

  9. Protooncogenes as mediators of apoptosis.

    Science.gov (United States)

    Teng, C S

    2000-01-01

    Apoptosis has been well established as a vital biological phenomenon that is important in the maintenance of cellular homeostasis. Three major protooncogene families and their encoded proteins function as mediators of apoptosis in various cell types and are the subject of this chapter. Protooncogenic proteins such as c-Myc/Max, c-Fos/c-Jun, and Bcl-2/Bax utilize a synergetic effect to enhance their roles in the pro- or antiapoptotic action. These family members activate and repress the expression of their target genes, control cell cycle progression, and execute programmed cell death. Repression or overproduction of these protooncogenic proteins induces apoptosis, which may vary as a result of either cell type specificity or the nature of the apoptotic stimuli. The proapoptotic and antiapoptotic proteins exert their effects in the membrane of cellular organelles. Here they generate cell-type-specific signals that activate the caspase family of proteases and their regulators for the execution of apoptosis.

  10. Amyloid precursor protein cooperates with c-KIT mutation/overexpression to regulate cell apoptosis in AML1-ETO-positive leukemia via the PI3K/AKT signaling pathway.

    Science.gov (United States)

    Yu, Guopan; Yin, Changxin; Jiang, Ling; Zheng, Zhongxin; Wang, Zhixiang; Wang, Chunli; Zhou, Hongsheng; Jiang, Xuejie; Liu, Qifa; Meng, Fanyi

    2016-09-01

    It has been reported that amyloid precursor protein (APP) promotes cell proliferation and metastasis in various types of solid cancers. In our previous study, we showed that APP is highly expressed and regulates leukemia cell migration in AML1‑ETO-positive (AE) leukemia. Whether APP is involved in the regulation of AE leukemia cell proliferation or apoptosis is unclear. In the present study we focused on the correlation of APP with c-KIT mutation/overexpression and cell proliferation and apoptosis in AE leukemia. APP and c-KIT expression detected by quantitative real-time (qPCR) method, and c-KIT mutations screened using PCR in bone marrow cells from 65 patients with AE leukemia before their first chemotherapy, were simultaneously assessed. Furthermore, the Kasumi-1 cell line was chosen as the cell model, and the APP gene was knocked down using siRNA technology. The correlation of cell cycle distribution and apoptosis and c-Kit expression with APP expression levels, as well as the regulation of the PI3K/AKT signaling pathway by APP were analyzed in the Kasumi-1 cell line. The results showed that peripheral white blood cell counts (P=0.008) and bone marrow cellularity (P=0.031), but not bone marrow blasts, were correlated with APP expression. Moreover, the patients with APP high expression had a significantly higher incidence of c-KIT mutations (Ptype and negative control cells, cell apoptosis, both early (P0.05). Moreover, the knockdown of APP markedly decreased c-KIT expression at both the transcription (as evidenced by qPCR analysis) and translation (as confirmed by CD117 assay and western blot analysis) levels, as well as p-AKT and its downstream targets including NF-κB, p53 and Bcl-2. In conclusion, APP may cooperate with c-KIT mutation/overexpression in the regulation of cell apoptosis but not proliferation in AE leukemia via the PI3K/AKT signaling pathway. PMID:27460334

  11. Rapamycin Sensitizes Glucocorticoid Resistant Acute Lymphoblastic Leukemia CEM-C1 Cells to Dexamethasone Induced Apoptosis through both mTOR Suppression and Up-Regulation and Activation of Glucocorticoid Receptor*

    Institute of Scientific and Technical Information of China (English)

    GUO Xia; ZHOU Chen Yan; LI Qiang; GAO Ju; ZHU Yi Ping; GU Ling; MA Zhi Gui

    2013-01-01

    Objective To explore the role of glucocorticoid (GC) receptor (GR) in rapamycin's reversion of GC resistance in human GC-resistant T-acute lymphoblastic leukemia (ALL) CEM-C1 cells. Methods CEM-C1 cells were cultured in vitro and treated with rapamycin at different concentrations with or without 1 μmol/L dexamethasone (Dex). 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) test was performed to assess cell proliferation. The cell cycle and cell apoptosis were analyzed by flow cytometry. The expression of GRα mRNA was determined by real-time quantitative RT-PCR. The expression of GR, p-70S6K, Mcl-1, and Bim proteins was detected by Western blot. Results When incubated with rapamycin at different concentrations, CEM-C1 cells showed significant growth inhibition in a time- and concentration-dependent manner. The growth inhibition was synergistically increased when CEM-C1 cells were treated with rapamycin plus 1 μmol/L Dex. CEM-C1 cells treated with rapamycin alone showed no apparent apoptosis, and were arrested at G0/G1 phase. After the treatment with Dex plus rapamycin, CEM-C1 cells demonstrated apparent apoptosis and increased the cell cycle arrested at G0/G1 phase. Rapamycin combined with Dex up-regulated GRα, phosphorylated GR(p-GR), and pro-apoptotic protein Bim-EL in CEM-C1 cells, but inhibited the expression of p-p70S6K, a downstream target protein of mTOR (mammalian target of rapamycin). Conclusion After the treatment with rapamycin plus Dex, Dex resistant CEM-C1 cells induce growth inhibition and apoptosis. The underlying mechanism may involve inhibition of the mTOR signaling pathway and also be associated with up-regulation of GR expression and activation of GC-GR signaling pathway.

  12. Crosstalk between apoptosis and inflammation in atherosclerosis

    NARCIS (Netherlands)

    Westra, Marijke Marianne

    2010-01-01

    In this thesis the role of several apoptosis regulating proteins in the development of atherosclerosis and atherosclerotic plaque stability is investigated. Apoptosis of different cell types in atherosclerotic plaques, such as macrophages and smooth muscle cells may inhibit or promote plaque develop

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

    Energy Technology Data Exchange (ETDEWEB)

    Changchien, Jung-Jung; Chen, Ying-Jung; Huang, Chia-Hui [Institute of Biomedical Sciences, National Sun Yat-Sen University, Kaohsiung 804, Taiwan (China); Cheng, Tian-Lu [Department of Biomedical Science and Environmental Biology, Kaohsiung Medical University, Kaohsiung 807, Taiwan (China); Lin, Shinne-Ren [Department of Medicinal and Applied Chemistry, Kaohsiung Medical University, Kaohsiung 807, Taiwan (China); Chang, Long-Sen, E-mail: lschang@mail.nsysu.edu.tw [Institute of Biomedical Sciences, National Sun Yat-Sen University, Kaohsiung 804, Taiwan (China); Department of Biotechnology, Kaohsiung Medical University, Kaohsiung 807, Taiwan (China)

    2015-04-01

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

  14. Killing effect of TNF-related apoptosis inducing ligand regulated by tetracycline on gastric cancer cell line NCI-N87

    Institute of Scientific and Technical Information of China (English)

    Xiao-Chao Wei; Xin-Juan Wang; Kai-Chen; Lei Zhang; Yu Liang; Xin-Li Lin

    2001-01-01

    AIM To clone the cDNA fragment of human TRAIL (TNFrelated apoptosis inducing ligand) into a tetracyclineregulated gene expression system, the RevTet-On system, transduce expression vectors into a gastric carcinoma cell line-NCl-N87 and examine the effects of controlled expression of TRAIL in vitro on the gastric carcinoma cells. METHODS The full-length cDNA of TRAIL was inserted into a vector under the control of the tetracyclineresponsive element (TRE) to obtain the plasmid pRevTRETRAIL, which was transfected into a packaging cell line PT67. In addition, vector pRev-Tet- On and pRevTRE were also transfected into PT67 separately. After hygromycin and G418 selection, the viral titer was determined. The medium containing retroviral vectors was collected and used to transduce a gastric carcinoma cell line NCI-N87.The resulting cell line NCI-N87-Tet-On-TRE-TRAIL and a control cell line, NCI-N87-Tet-On-TRE, were established.TRAIL expression in the cell line was induced by incubating cells with doxycycline (Dox), which is a tetracycline analogue. The killing effect on gastric carcinoma cells was analyzed after induction. RESULTS The recombinant plasmid pRev-TRE-TRAIL was constructed. After hygromycin or G418 selection, the producer cell lines PT67-TRE, PT67-TRE-TRAIL and PT67TetOn were obtained, with titers of about 108CFU@ L-1 By transducing NCI-N87 cells with retroviral vectors from these cell lines, stable cell lines NCI-N87-Tet-On-TRETRAIL (NN3T) and control cell line NCI-N87-Tet-On-TRE (NN2T) were established. The growth curves of the selected cell lines were the same with the wild type NCIN87. When Dox was added, cell death was obvious in the test groups (29% -77%), whereas no difference was observed in control and wild type cell lines. With the addition of a medium from the test group, human leukemia cell line Jurkat was activated till death (83%), indicating the secretion of active TRAIL proteins from the test cells to the medium. CONCLUSION With the use of the

  15. The cellular decision between apoptosis and autophagy

    Institute of Scientific and Technical Information of China (English)

    Yong-Jun Fan; Wei-Xing Zong

    2013-01-01

    Apoptosis and autophagy are important molecular processes that maintain organismal and cellular homeostasis,respectively.While apoptosis fulfills its role through dismantling damaged or unwanted cells,autophagy maintains cellular homeostasis through recycling selective intracellular organelles and molecules.Yet in some conditions,autophagy can lead to cell death.Apoptosis and autophagy can be stimulated by the same stresses.Emerging evidence indicates an interplay between the core proteins in both pathways,which underlies the molecular mechanism of the crosstalk between apoptosis and autophagy.This review summarizes recent literature on molecules that regulate both the apoptotic and autophagic processes.

  16. Induction of the liver cancer-down-regulated long noncoding RNA uc002mbe.2 mediates trichostatin-induced apoptosis of liver cancer cells

    OpenAIRE

    Yang, Hui; Zhong, Yun; Xie, Hui; Lai, Xiaobo; Xu, Miqing; Nie, Yuqiang; Liu, Shiming; Wan, Yu-Jui Yvonne

    2013-01-01

    Differential expression of long non-coding RNAs (lncRNAs) plays critical roles in hepatocarcinogenesis. Considerable attention has focused on the antitumor effect of histone deacetylase inhibitor (Trichostatin A, TSA) as well as the coding gene expression-induced apoptosis of cancer cells. However, it is not known whether lncRNA has a role in TSA-induced apoptosis of human hepatocellular carcinoma (HCC) cells. The global expression of lncRNAs and coding genes was analyzed with the Human LncRN...

  17. Inhibitor of apoptosis proteins: new therapeutic targets in hematological cancer?

    NARCIS (Netherlands)

    Graaf, A.O. de; Witte, T.J.M. de; Jansen, J.H.

    2004-01-01

    Apoptosis is an essential process for the selection and survival of lymphocytes. Resistance to apoptosis can promote malignant transformation of hematopoietic cells. Proteins that regulate apoptosis may therefore be critically involved in the development of hematological cancer. A delicate balance b

  18. CpG methyltransferase induced down-regulation of claudin-7,-8 and its effects on proliferation and apoptosis of human colorectal cancer HT-29 cells

    Institute of Scientific and Technical Information of China (English)

    王文辉

    2013-01-01

    Objective To explore the regulatory effect of CpG methyltransferase (M.SssI) on expression of claudin-7and claudin-8,promoting apoptosis and inhibiting proliferation of human colorectal cancer HT-29 cells.Methods HT-29 cells were treated with M.SssI (50 U/ml) for

  19. Ethyl pyruvate inhibits proliferation and induces apoptosis of hepatocellular carcinoma via regulation of the HMGB1–RAGE and AKT pathways

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, Ping; Dai, Weiqi; Wang, Fan; Lu, Jie; Shen, Miao; Chen, Kan; Li, Jingjing; Zhang, Yan; Wang, Chengfen; Yang, Jing; Zhu, Rong; Zhang, Huawei; Zheng, Yuanyuan; Guo, Chuan-Yong, E-mail: guochuanyong@hotmail.com; Xu, Ling, E-mail: xuling606@sina.com

    2014-01-24

    Highlights: • Ethyl pyruvate inhibits liver cancer. • Promotes apoptosis. • Decreased the expression of HMGB1, p-Akt. - Abstract: Ethyl pyruvate (EP) was recently identified as a stable lipophilic derivative of pyruvic acid with significant antineoplastic activities. The high mobility group box-B1 (HMGB1)–receptor for advanced glycation end-products (RAGE) and the protein kinase B (Akt) pathways play a crucial role in tumorigenesis and development of many malignant tumors. We tried to observe the effects of ethyl pyruvate on liver cancer growth and explored its effects in hepatocellular carcinoma model. In this study, three hepatocellular carcinoma cell lines were treated with ethyl pyruvate. An MTT colorimetric assay was used to assess the effects of EP on cell proliferation. Flow cytometry and TUNEL assays were used to analyze apoptosis. Real-time PCR, Western blotting and immunofluorescence demonstrated ethyl pyruvate reduced the HMGB1–RAGE and AKT pathways. The results of hepatoma orthotopic tumor model verified the antitumor effects of ethyl pyruvate in vivo. EP could induce apoptosis and slow the growth of liver cancer. Moreover, EP decreased the expression of HMGB1, RAGE, p-AKT and matrix metallopeptidase-9 (MMP9) and increased the Bax/Bcl-2 ratio. In conclusion, this study demonstrates that ethyl pyruvate induces apoptosis and cell-cycle arrest in G phase in hepatocellular carcinoma cells, plays a critical role in the treatment of cancer.

  20. Cholesterol overload induces apoptosis in SH-SY5Y human neuroblastoma cells through the up regulation of flotillin-2 in the lipid raft and the activation of BDNF/Trkb signaling.

    Science.gov (United States)

    Huang, Yen-Ning; Lin, Ching-I; Liao, Hsiang; Liu, Chin-Yu; Chen, Yue-Hua; Chiu, Wan-Chun; Lin, Shyh-Hsiang

    2016-07-22

    Epidemiological investigations have shown that Alzheimer's disease (AD) is one of the most common neurodegenerative diseases. It has been indicated that the cholesterol concentration in the brain of AD patients is higher than that in normal people. In this study, we investigated the effects of cholesterol concentrations, 0, as the control, 3.125, 12.5, and 25μM, on cholesterol metabolism, neuron survival, AD-related protein expressions, and cell morphology and apoptosis using SH-SY5Y human neuroblastoma cells. We observed that expressions of cholesterol hydroxylase (Cyp46), flotillin-2 (a marker of lipid raft content), and truncated tyrosine kinase B (TrkBtc) increased, while expressions of brain-derived neurotrophic factor (BDNF) and full-length TrkB (TrkBfl) decreased as the concentration of cholesterol loading increased. Down-regulation of the PI3K-Akt-glycogen synthase kinase (GSK)-3β cascade and cell apoptosis were also observed at higher concentrations of cholesterol, along with elevated levels of β-amyloid (Aβ), β-secretase (BACE), and reactive oxygen species (ROS). In conclusion, we found that cholesterol overload in neuronal cells imbalanced the cholesterol homeostasis and increased the protein expressions causing cell apoptosis, which illustrates the neurodegenerative pathology of abnormally elevated cholesterol concentrations found in AD patients.

  1. Beta-asarone induces LoVo colon cancer cell apoptosis by up-regulation of caspases through a mitochondrial pathway in vitro and in vivo.

    Science.gov (United States)

    Zou, Xi; Liu, Shen-Lin; Zhou, Jin-Yong; Wu, Jian; Ling, Bo-Fan; Wang, Rui-Ping

    2012-01-01

    Beta-asarone is one of the main bioactive constituents in traditional Chinese medicine Acorus calamu. Previous studies have shown that it has antifungal and anthelmintic activities. However, little is known about its anticancer effects. This study aimed to determine inhibitory effects on LoVo colon cancer cell proliferation and to clarify the underlying mechanisms in vitro and in vivo. Dose-response and time-course anti-proliferation effects were examined by MTT assay. Our results demonstrated that LoVo cell viability showed dose- and time-dependence on β-asarone. We further assessed anti-proliferation effects as β-asarone-induced apoptosis by annexin V-fluorescein isothiocyanate/propidium iodide assay using a flow cytometer and observed characteristic nuclear fragmentation and chromatin condensation of apoptosis by microscopy. Moreover, we found the apoptosis to be induced through the mitochondrial/caspase pathway by decreasing mitochondrial membrane potential (MMP) and reducing the Bcl-2-to-Bax ratio, in addition to activating the caspase-9 and caspase-3 cascades. Additionally, the apoptosis could be inhibited by a pan-caspase inhibitor, carbobenzoxy-valyl-alanyl-aspartyl-[O-methyl]-fluoromethylketone (Z-VAD-FMK). When nude mice bearing LoVo tumor xenografts were treated with β-asarone, tumor volumes were reduced and terminal deoxynucleotide transferase-mediated dUTP nick end labeling (TUNEL) assays of excised tissue also demonstrated apoptotic changes. Taken together, these findings for the first time provide evidence that β-asarone can suppress the growth of colon cancer and the induced apoptosis is possibly mediated through mitochondria/caspase pathways.

  2. In vivo regulation of colonic cell proliferation, differentiation, apoptosis, and P27Kip1 by dietary fish oil and butyrate in rats.

    Science.gov (United States)

    Hong, Mee Young; Turner, Nancy D; Murphy, Mary E; Carroll, Raymond J; Chapkin, Robert S; Lupton, Joanne R

    2015-11-01

    We have shown that dietary fish oil is protective against experimentally induced colon cancer, and the protective effect is enhanced by coadministration of pectin. However, the underlying mechanisms have not been fully elucidated. We hypothesized that fish oil with butyrate, a pectin fermentation product, protects against colon cancer initiation by decreasing cell proliferation and increasing differentiation and apoptosis through a p27(Kip1)-mediated mechanism. Rats were provided diets of corn or fish oil, with/without butyrate, and terminated 12, 24, or 48 hours after azoxymethane (AOM) injection. Proliferation (Ki-67), differentiation (Dolichos Biflorus Agglutinin), apoptosis (TUNEL), and p27(Kip1) (cell-cycle mediator) were measured in the same cell within crypts in order to examine the coordination of cell cycle as a function of diet. DNA damage (N(7)-methylguanine) was determined by quantitative IHC analysis. Dietary fish oil decreased DNA damage by 19% (P = 0.001) and proliferation by 50% (P = 0.003) and increased differentiation by 56% (P = 0.039) compared with corn oil. When combined with butyrate, fish oil enhanced apoptosis 24 hours after AOM injection compared with a corn oil/butyrate diet (P = 0.039). There was an inverse relationship between crypt height and apoptosis in the fish oil/butyrate group (r = -0.53, P = 0.040). The corn oil/butyrate group showed a positive correlation between p27(Kip1) expression and proliferation (r = 0.61, P = 0.035). These results indicate the in vivo effect of butyrate on apoptosis and proliferation is dependent on dietary lipid source. These results demonstrate the presence of an early coordinated colonocyte response by which fish oil and butyrate protects against colon tumorigenesis.

  3. Tubeimoside-1 induces glioma apoptosis through regulation of Bax/Bcl-2 and the ROS/Cytochrome C/Caspase-3 pathway

    Directory of Open Access Journals (Sweden)

    Jia G

    2015-01-01

    Full Text Available Geng Jia,1,* Qiang Wang,2,* Rong Wang,2,* Danni Deng,2 Lian Xue,2 Naiyuan Shao,1 Yi Zhang,1 Xiwei Xia,1 Feng Zhi,2 Yilin Yang1,2 1Department of Neurosurgery, Third Affiliated Hospital of Soochow University, Jiangsu, People’s Republic of China; 2Modern Medical Research Center, Third Affiliated Hospital of Soochow University, Jiangsu, People’s Republic of China * These authors contributed equally to this workBackground: Tubeimoside-1 (TBMS1 is a natural compound isolated from tubeimoside, which has been widely used as a traditional Chinese herbal medicine. The purpose of the present study is to investigate the anti-tumor effect and the underling mechanism of TBMS1 on glioma cancer cells.Methods: The MTT assay was performed to evaluate the effect of TBMS1 on glioma cell proliferation. The fluorescent microscopy and flow cytometry analysis were performed to evaluate the effect of TBMS1 on glioma cell apoptosis. The Western blot analysis was used to evaluate the protein change.Results: TBMS1 inhibited glioma cancer cell proliferation in a dose- and time-dependent manner. Fluorescent microscopy and flow cytometry analysis demonstrated that TBMS1 induced glioma cell apoptosis in a concentration-dependent manner. Western blotting showed that TBMS1 induced apoptosis by increasing the expression of Bax and downregulating the level of Bcl-2. Furthermore, we found that TBMS1 induced apoptosis by increasing the concentration of reactive oxygen species through the release of Cytochrome C and activation of Caspase-3.Conclusion: These findings indicate that TBMS1 may be developed as a possible therapeutic agent for the management of glioma. Keywords: Tubeimoside-1, glioma, proliferation, apoptosis

  4. Paclitaxel induces apoptosis in human gastric carcinoma cells

    Institute of Scientific and Technical Information of China (English)

    Hai-Bo Zhou; Ju-Ren Zhu

    2003-01-01

    AIM: To investigate the apoptosis in gastric cancer cells induced by paclitaxel, and the relation between this apoptosis and expression of Bcl-2 and Bax.METHODS: In in vitro experiments, MTT assay was used to determine the cell growth inhibitory rate. Transmission electron microscope and TUNEL staining method were used to quantitatively and qualitively detect the apoptosis status of gastric cancer cell line SGC-7901 before and after the paditaxel treatment. Immunohistochemical staining was used to detect the expression of apoptosis-regulated gene Bcl-2and Bax.RESULTS: Paclitaxel inhibited the growth of gastric cancer cell line SGC-7901 in a dose-and time-dependent manner.Paclitaxel induced SGC-7901 cells to undergo apoptosis with typically apoptotic characteristics, including morphological changes of chromatin condensation, chromatin crescent formation, nucleus fragmentation and apoptotic body formation. Paclitaxel could reduce the expression of apoptosis-regulated gene Bcl-2, and improve the expression of apoptosis-regulated gene Bax.CONCLUSION: Paclitaxel is able to induce the apoptosis in gastric cancer. This apoptosis may be mediated by downexpression of apoptosis-regulated gene Bcl-2 and upexpression of apoptosis-regulated gene Bax.

  5. Diospyrin derivative, an anticancer quinonoid, regulates apoptosis at endoplasmic reticulum as well as mitochondria by modulating cytosolic calcium in human breast carcinoma cells

    International Nuclear Information System (INIS)

    Highlights: ► Diospyrin diethylether (D7) caused oxidative stress-dependent activation of PC-PLC. ► Activated PC-PLC induced a sustained-release of Ca2+ from endoplasmic reticulum. ► The elevated cytosolic Ca+2 led to the calpain-caspase12 dependent apoptosis. ► D7-Induced Ca+2 also found to accentuate the mitochondrial pathway of apoptosis. -- Abstract: Diospyrin diethylether (D7), a bisnaphthoquinonoid derivative, exhibited an oxidative stress-dependent apoptosis in several human cancer cells and tumor models. The present study was aimed at evaluation of the increase in cytosolic calcium [Ca2+]c leading to the apoptotic cell death triggered by D7 in MCF7 human breast carcinoma cells. A phosphotidylcholine-specific phospholipase C (PC-PLC) inhibitor, viz. U73122, and an antioxidant, viz. N-acetylcysteine, could significantly prevent the D7-induced rise in [Ca2+]c and PC-PLC activity. Using an endoplasmic reticulum (ER)-Ca2+ mobilizer (thapsigargin) and an ER-IP3R antagonist (heparin), results revealed ER as a major source of [Ca2+]c which led to the activation of calpain and caspase12, and cleavage of fodrin. These effects including apoptosis were significantly inhibited by the pretreatment of Bapta-AM (a cell permeable Ca2+-specific chelator), or calpeptin (a calpain inhibitor). Furthermore, D7-induced [Ca2+]c was found to alter mitochondrial membrane potential and induce cytochrome c release, which was inhibited by either Bapta-AM or ruthenium red (an inhibitor of mitochondrial Ca2+ uniporter). Thus, these results provided a deeper insight into the D7-induced redox signaling which eventually integrated the calcium-dependent calpain/caspase12 activation and mitochondrial alterations to accentuate the induction of apoptotic cell death.

  6. N-acetylcysteine attenuates ischemia-reperfusion-induced apoptosis and autophagy in mouse liver via regulation of the ROS/JNK/Bcl-2 pathway.

    Directory of Open Access Journals (Sweden)

    Chengfen Wang

    Full Text Available BACKGROUND: Hepatic ischemia-reperfusion injury (HIRI remains a pivotal clinical problem after hemorrhagic shock, transplantation, and some types of toxic hepatic injury. Apoptosis and autophagy play important roles in cell death during HIRI. It is also known that N-acetylcysteine (NAC has significant pharmacologic effects on HIRI including elimination of reactive oxygen species (ROS and attenuation of hepatic apoptosis. However, the effects of NAC on HIRI-induced autophagy have not been reported. In this study, we evaluated the effects of NAC on autophagy and apoptosis in HIRI, and explored the possible mechanism involved. METHODS: A mouse model of segmental (70% hepatic warm ischemia was adopted to determine hepatic injury. NAC (150 mg/kg, a hepatoprotection agent, was administered before surgery. We hypothesized that the mechanism of NAC may involve the ROS/JNK/Bcl-2 pathway. We evaluated the expression of JNK, P-JNK, Bcl-2, Beclin 1 and LC3 by western blotting and immunohistochemical staining. Autophagosomes were evaluated by transmission electron microscopy (TEM. RESULTS: We found that ALT, AST and pathological changes were significantly improved in the NAC group. Western blotting analysis showed that the expression levels of Beclin 1 and LC3 were significantly decreased in NAC-treated mice. In addition, JNK, p-JNK, Bax, TNF-α, NF-κB, IL2, IL6 and levels were also decreased in NAC-treated mice. CONCLUSION: NAC can prevent HIRI-induced autophagy and apoptosis by influencing the JNK signal pathway. The mechanism is likely to involve attenuation of JNK and p-JNK via scavenged ROS, an indirect increase in Bcl-2 level, and finally an alteration in the balance of Beclin 1 and Bcl-2.

  7. Toll-like Receptor 3 Regulates Angiogenesis and Apoptosis in Prostate Cancer Cell Lines through Hypoxia-Inducible Factor 1α

    OpenAIRE

    Alessio Paone; Roberta Galli; Chiara Gabellini; Dmitriy Lukashev; Donatella Starace; Agnes Gorlach; Paola De Cesaris; Elio Ziparo; Donatella Del Bufalo; Sitkovsky, Michail V.; Antonio Filippini; Anna Riccioli

    2010-01-01

    Toll-like receptors (TLRs) recognize microbial/viral-derived components that trigger innate immune response and conflicting data implicate TLR agonists in cancer, either as protumor or antitumor agents. We previously demonstrated that TLR3 activation mediated by its agonist poly(I:C) induces antitumor signaling, leading to apoptosis of prostate cancer cells LNCaP and PC3 with much more efficiency in the former than in the second more aggressive line. The transcription factor hypoxia-inducible...

  8. Toll-like Receptor 3 Regulates Angiogenesis and Apoptosis in Prostate Cancer Cell Lines through Hypoxia-Inducible Factor 1α1

    OpenAIRE

    Paone, Alessio; Galli, Roberta; Gabellini, Chiara; Lukashev, Dmitriy; Starace, Donatella; Gorlach, Agnes; Cesaris, Paola; Ziparo, Elio; Del Bufalo, Donatella; Sitkovsky, Michail V.; Filippini, Antonio; Riccioli, Anna

    2010-01-01

    Toll-like receptors (TLRs) recognize microbial/viral-derived components that trigger innate immune response and conflicting data implicate TLR agonists in cancer, either as protumor or antitumor agents. We previously demonstrated that TLR3 activation mediated by its agonist poly(I:C) induces antitumor signaling, leading to apoptosis of prostate cancer cells LNCaP and PC3 with much more efficiency in the former than in the second more aggressive line. The transcription factor hypoxia-inducible...

  9. Low fucose containing bacterial polysaccharide facilitate mitochondria-dependent ROS-induced apoptosis of human lung epithelial carcinoma via controlled regulation of MAPKs-mediated Nrf2/Keap1 homeostasis signaling.

    Science.gov (United States)

    Chowdhury, Sougata Roy; Sengupta, Suman; Biswas, Subir; Sen, Ramkrishna; Sinha, Tridib Kumar; Basak, Ratan Kumar; Adhikari, Basudam; Bhattacharyya, Arindam

    2015-12-01

    Reactive oxygen species (ROS), the key mediators of cellular oxidative stress and redox dysregulation involved in cancer initiation and progression, have recently emerged as promising targets for anticancer drug discovery. Continuous free radical assault upsets homeostasis in cellular redox system and regulates the associated signaling pathways to mediate stress-induced cell death. This study investigates the dose-specific pro-oxidative behavior of a bacterial fucose polysaccharide, which attenuated proliferation of different cancer cells. In the fermentation process, Bacillus megaterium RB-05 [GenBank Accession Number HM371417] was found to biosynthesize a polysaccharide with low-fucose content (4.9%), which conferred the maximum anti-proliferative activity (750 µg/mL) against human lung cancer epithelial cells (A549) during preliminary screening. Structural elucidation and morphological characterization of the duly purified polysaccharide was done using HPLC, GC-MS, (1)H/(13)C NMR, and microscopy. The polysaccharide exhibited concentration- and time-dependent anti-proliferative effects against A549 cells by inducing intracellular ROS level and regulating the mitochondrial membrane-permeability following the apoptotic pathway. This process encompasses activation of caspase-8/9/3/7, increase in the ratio of Bax/Bcl2 ratio, translocation of Bcl2-associated X protein (Bax) and cytochrome c, decrease in expression of anti-apoptotic members of Bcl2 family, and phosphorylation of mitogen activated protein kinases (MAPKs). Apoptosis was attenuated upon pretreatment with specific caspase-inhibitors. Simultaneously, during apoptosis, the ROS-mediated stress as well as activated MAPKs triggered nuclear translocation of transcription factors like nuclear factor (erythroid-derived)-like 2 (Nrf2) and promoted further transcription of downstream cytoprotective genes, which somehow perturbed the chemotherapeutic efficacy of the polysaccharide, although using CuPP, a chemical

  10. Berberine induces mitochondrial apoptosis of EBV-transformed B cells through p53-mediated regulation of XAF1 and GADD45α.

    Science.gov (United States)

    Park, Ga Bin; Park, Sang Hyun; Kim, Daejin; Kim, Yeong Seok; Yoon, Sung Ho; Hur, Dae Young

    2016-07-01

    Berberine exhibits antiproliferative or cytotoxic effects against various cancers. ROS and wild-type p53 play a critical role in berberine-induced cytotoxic effects. In this study, we investigated the correlation between XAF1 and functional p53 in EBV-transformed B cells or cancerous B cells after treatment with berberine. Berberine decreased cell viability and induced apoptosis through a mitochondria-dependent pathway in EBV-transformed B cells and cancerous B cells, but not in normal peripheral blood mononuclear cells. Activated p53 and its downstream targets XAF1 and GADD45α interacted with PUMA, Bax, and Bim in mitochondria after treatment with berberine. Blocking phosphorylation of p38/JNK MAPK and treatment with PFT-α, a selective p53 inhibitor, effectively prevented apoptosis and the upregulation of phosphorylated p53, XAF1, and GADD45α. NAC, a ROS scavenger, also suppressed berberine-induced mitochondria disruption and the whole apoptotic process via restoration of p53-related proteins and proapoptotic Bcl-2 family proteins. Taken together, our results suggest that ROS generation might be a predisposing event in berberine-induced mitochondrial apoptosis in EBV-transformed B cells through the upregulation of XAF1 and GADD45α expression by MAPK and functional p53. PMID:27121748

  11. PI3K/Akt signaling pathway involved in regulation of T lymphocyte activation and apoptosis mediated by CD3e

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    To study the expression and kinase activity of phosphatidylinositol 3′-kinase (PI3K) and protein kinase B (PKB or Akt) during activation and apoptosis of human Jurkat T lymphocytes (TJK) with stable expression of CD8e chimera fused human CD8a extracellular and transmembra-ne domains to intracellular domain of mouse CD3e, Western blot, kinase activities detection and immunoprecipitation were carried out. It was shown that Jurkat cells with expres-sion of wild type chimera CD8e died by apoptosis after con-tinuous stimulation of anti-CD8 monoclonal antibody. The expressions of PI3K and Akt, and the kinase activity of Akt remarkably increased during the process. However, this phenomenon did not occur in the Jurkat cells (T1JK) with expression of the mutant of CD8e chimera (Y170F), sug-gesting that PI3K/Akt signaling pathway is involved in acti-vation and apoptosis of T lymphocyte mediated by CD3e.

  12. Processing of Kansui Roots Stir-Baked with Vinegar Reduces Kansui-Induced Hepatocyte Cytotoxicity by Decreasing the Contents of Toxic Terpenoids and Regulating the Cell Apoptosis Pathway

    Directory of Open Access Journals (Sweden)

    Xiaojing Yan

    2014-06-01

    Full Text Available Euphorbia kansui is a Traditional Chinese Medicine widely used for the treatment of oedema, ascites and asthma. However, its serious hepatotoxicity hinders its safe clinical application. The process of stir-baking with vinegar is regularly used to reduce the toxicity of kansui. Up till now, the exact mechanism of the reduction in hepatotoxicity of kansui stir-baked with vinegar has been poorly defined. In this study, decreased  contents of five diterpene and one triterpene in kansui (GS-1 after stir-baking with vinegar (GS-2 was investigated by UPLC-QTOF/MS. Flow cytometry and Hoechst staining were used to show that the stir-baking with vinegar process reduces kansui-induced cell apoptosis. Furthermore, the result also indicated that kansui stir-baked with vinegar protects LO2 cells from apoptosis by increasing the cell mitochondrial membrane potential (ΔΨm, decreasing the release of cytochrome c and inhibiting the activities of caspase-9 and caspase-3 as evidenced by means of high content screening (HCS, ELISA and western blotting. These results suggested that the stir-baking vinegar could reduce the hepatotoxicity of kansui by effectively decreasing the contents of toxic terpenoids and inhibiting the intrinsic pathway of hepatocyte cell apoptosis. In conclusion, the study provided significant data for promoting safer and better clinical use of this herb.

  13. Changes in barrier health status of the gill for grass carp (Ctenopharyngodon idella) during valine deficiency: Regulation of tight junction protein transcript, antioxidant status and apoptosis-related gene expression.

    Science.gov (United States)

    Feng, Lin; Luo, Jian-Bo; Jiang, Wei-Dan; Liu, Yang; Wu, Pei; Jiang, Jun; Kuang, Sheng-Yao; Tang, Ling; Zhang, Yong-An; Zhou, Xiao-Qiu

    2015-08-01

    This study investigated the effects of dietary valine on tight junction protein transcription, antioxidant status and apoptosis on grass carp gills (Ctenopharyngodon idella). Fish were fed six different experimental diets containing graded levels of valine (4.3, 8.0, 10.6, 13.1, 16.7, 19.1 g/kg). The results indicated that valine deficiency decreased Claudin b, Claudin 3, Occludin and ZO-1 transcription and increased Claudin 15 expression in the fish gill (P valine deficiency and valine supplementation did not have a significant effect on Claudin c and Claudin 12 expression in grass carp gills (P > 0.05). Valine deficiency also disrupted antioxidant status in the gill by decreasing anti-superoxide radicals and hydroxyl radical capacity, glutathione contents and the activities and mRNA levels of Cu/Zn superoxide dismutase (SOD1), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR) and glutathione-S-transferase (GST) (P valine deficiency induced DNA fragmentation via the up-regulation of Caspase 3, Caspase 8 and Caspase 9 expressions (P valine deficiency impaired the structural integrity of fish gill by disrupted fish antioxidant defenses and regulating the expression of tight junction protein, cytokines, antioxidant enzymes, NF-κB p65, IκBα, TOR, Nrf2, Keap1 and apoptosis-related genes in the fish gill.

  14. An Experimental Study on the Role of Nuclear Factor-κB in the Signal Conduction of Protein Kinase C Regulating the Proliferation and Apoptosis of T Lymphocytes in Asthma

    Institute of Scientific and Technical Information of China (English)

    熊维宁; 徐永健; 张珍祥; 王孝养

    2004-01-01

    To explore the role of nuclear factor-κB(NF-κB) in the signal pathway of protein kinase C (PKC) regulating the proliferation and apoptosis of T lymphocytes in asthma. T lymphocytes were isolated from the asthmatic model of guinea pigs and the asthmatic patients. Either the T cells stimulated with PMA alone or those stimulated with PMA together with pyrrolidine dithiocarbamate (PDTC) were incubated for 1 and 24 h. The proliferation of and the presence of NF-κB in the cells incubated for 1 h were observed by MTT and immunohistochemical staining, respectivelyAnd the cells incubated for 24 h were observed for the apoptosis by TUNEL. All the assays were paralleled with controls, and all the data were analyzedstatistically with the software SAS. The percentage of cells of nuclear positive staining of NF-scB and the proliferation of T lymphocytes from asthmatic guinea pigs and asthmatic patients stimulated with PMA were significantly higher than those of T lymphocytes from asthmatic guinea pigs and asthmatic patients stimulated without PMA respectively ( P < 0.01 ) and those of T lymphocytes from normal control guinea pigs and normal control persons stimulated with PMA respectively ( P < 0.01 ), and were significantly reduced by PDTC (P < 0.01 ). The apoptosis index of T lymphocytes from asthmatic guinea pigs and asthmatic patients stimulated with PMA were significantly lower than those of T lymphocytes from asthmatic guinea pigs and asthmatic patients stimulated without PMA respectively ( P < 0.01 ) and those of T lymphocytes from normal control guine apigs and normal control persons stimulated with PMA respectively ( P < 0.01 ), and were significantly induced by PDTC ( P< 0.01 ). There were good positive correlation between the percentage of cells of nuclear staining of NF-κB ofT lymphocytes and the proliferation of T lymphocytes ( r = 0.51-0.72, P < 0.001 ), and also good negative correlation between the percentage of cells of nuclear staining of NF-scB and the

  15. 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

  16. 17β-Estradiol regulates cell proliferation, colony formation, migration, invasion and promotes apoptosis by upregulating miR-9 and thus degrades MALAT-1 in osteosarcoma cell MG-63 in an estrogen receptor-independent manner

    Energy Technology Data Exchange (ETDEWEB)

    Fang, Dengfeng; Yang, Hui; Lin, Jing; Teng, Yi; Jiang, Yingying; Chen, Jiao; Li, Yu, E-mail: yuli_scu@163.com

    2015-02-20

    In bone, different concentration of estrogen leads to various of physiological processes in osteoblast, such as the proliferation, migration, and apoptosis in an estrogen receptor-dependent manner. But little was known about the estrogen effects on osteosarcoma (OS). In this study, OS cell MG-63 was treated with low (1 nM) or high (100 nM) dose of 17β-Estradiol (E2) with the presence or absence of estrogen receptor α (ERα), for evaluating the E2 effects on proliferation, migration, invasion, colony formation and apoptosis. Consistent with a previous study, high dose of E2 treatment dramatically downregulated expressing level of long non-coding RNA metastasis associated lung adenocarcinoma transcript 1 (MALAT-1). The observation of upregulation of miR-9 after a high dose of E2 treatment indicated the cause of MALAT-1 reduction. Downregulation of MALAT-1 promoted the combination of SFPQ/PTBP2 complex. It was also observed that the proliferation, migration, invasion, colony formation and apoptosis of OS cells were remarkably affected by high dose of E2 treatment, but not by low dose, in an ERα independent manner. Furthermore, the abolishment of the effects on these physiological processes caused by ectopic expression of miR-9 ASOs suggested the necessity of miR-9 in MALAT-1 regulation. Here we found that the high dose of E2 treatment upregulated miR-9 thus posttranscriptionally regulated MALAT-1 RNA level in OS cells, and then the downregulation of MALAT-1 inhibited cell proliferation, migration, invasion and epithelial–mesenchymal transition (EMT) processes in the E2-dose dependent and ER-independent ways. - Highlights: • E2 affects osteosarcoma cell MG-63 in an Estrogen receptor-independent way. • High dose of E2 treatment upregulates miR-9 which target to MALAT-1 RNA. • Upregulated miR-9 degrades MALAT-1 and thus affects combination of SFPQ/PTBP2. • E2 treatment block cell proliferation, colony formation, mobility, and enhance apoptosis.

  17. Radiation response and regulation of apoptosis induced by a combination of TRAIL and CHX in cells lacking mitochondrial DNA: A role for NF-{kappa}B-STAT3-directed gene expression

    Energy Technology Data Exchange (ETDEWEB)

    Ivanov, Vladimir N., E-mail: vni3@columbia.edu; Ghandhi, Shanaz A.; Zhou, Hongning; Huang, Sarah X.; Chai, Yunfei; Amundson, Sally A.; Hei, Tom K.

    2011-07-01

    Mitochondrial DNA depleted ({rho}{sup 0}) human skin fibroblasts (HSF) with suppressed oxidative phosphorylation were characterized by significant changes in the expression of 2100 nuclear genes, encoding numerous protein classes, in NF-{kappa}B and STAT3 signaling pathways, and by decreased activity of mitochondrial death pathway, compared to the parental {rho}{sup +} HSF. In contrast, the extrinsic TRAIL/TRAIL-Receptor mediated death pathway remained highly active, and exogenous TRAIL in a combination with cycloheximide (CHX) induced higher levels of apoptosis in {rho}{sup 0} cells compared to {rho}{sup +} HSF. Global gene expression analysis using microarray and qRT-PCR demonstrated that mRNA expression levels of many growth factors and their adaptor proteins (FGF13, HGF, IGFBP4, IGFBP6, and IGFL2), cytokines (IL6, {Oota}L17{Beta}, {Oota}L18, {Oota}L19, and {Oota}L28{Beta}) and cytokine receptors (IL1R1, IL21R, and IL31RA) were substantially decreased after mitochondrial DNA depletion. Some of these genes were targets of NF-{kappa}B and STAT3, and their protein products could regulate the STAT3 signaling pathway. Alpha-irradiation further induced expression of several NF-{kappa}B/STAT3 target genes, including IL1A, IL1B, IL6, PTGS2/COX2 and MMP12, in {rho}{sup +} HSF, but this response was substantially decreased in {rho}{sup 0} HSF. Suppression of the IKK-NF-{kappa}B pathway by the small molecular inhibitor BMS-345541 and of the JAK2-STAT3 pathway by AG490 dramatically increased TRAIL-induced apoptosis in the control and irradiated {rho}{sup +} HSF. Inhibitory antibodies against IL6, the main activator of JAK2-STAT3 pathway, added into the cell media, also increased TRAIL-induced apoptosis in HSF, especially after alpha-irradiation. Collectively, our results indicated that NF-{kappa}B activation was partially lost in {rho}{sup 0} HSF resulting in downregulation of the basal or radiation-induced expression of numerous NF-{kappa}B targets, further suppressing IL6

  18. 17β-Estradiol regulates cell proliferation, colony formation, migration, invasion and promotes apoptosis by upregulating miR-9 and thus degrades MALAT-1 in osteosarcoma cell MG-63 in an estrogen receptor-independent manner

    International Nuclear Information System (INIS)

    In bone, different concentration of estrogen leads to various of physiological processes in osteoblast, such as the proliferation, migration, and apoptosis in an estrogen receptor-dependent manner. But little was known about the estrogen effects on osteosarcoma (OS). In this study, OS cell MG-63 was treated with low (1 nM) or high (100 nM) dose of 17β-Estradiol (E2) with the presence or absence of estrogen receptor α (ERα), for evaluating the E2 effects on proliferation, migration, invasion, colony formation and apoptosis. Consistent with a previous study, high dose of E2 treatment dramatically downregulated expressing level of long non-coding RNA metastasis associated lung adenocarcinoma transcript 1 (MALAT-1). The observation of upregulation of miR-9 after a high dose of E2 treatment indicated the cause of MALAT-1 reduction. Downregulation of MALAT-1 promoted the combination of SFPQ/PTBP2 complex. It was also observed that the proliferation, migration, invasion, colony formation and apoptosis of OS cells were remarkably affected by high dose of E2 treatment, but not by low dose, in an ERα independent manner. Furthermore, the abolishment of the effects on these physiological processes caused by ectopic expression of miR-9 ASOs suggested the necessity of miR-9 in MALAT-1 regulation. Here we found that the high dose of E2 treatment upregulated miR-9 thus posttranscriptionally regulated MALAT-1 RNA level in OS cells, and then the downregulation of MALAT-1 inhibited cell proliferation, migration, invasion and epithelial–mesenchymal transition (EMT) processes in the E2-dose dependent and ER-independent ways. - Highlights: • E2 affects osteosarcoma cell MG-63 in an Estrogen receptor-independent way. • High dose of E2 treatment upregulates miR-9 which target to MALAT-1 RNA. • Upregulated miR-9 degrades MALAT-1 and thus affects combination of SFPQ/PTBP2. • E2 treatment block cell proliferation, colony formation, mobility, and enhance apoptosis

  19. Apoptosis-modulating interaction of the neuregulin/erbB pathway with anthracyclines in regulating Bcl-xS and Bcl-xL in cardiomyocytes.

    Science.gov (United States)

    Rohrbach, Susanne; Muller-Werdan, Ursula; Werdan, Karl; Koch, Susanne; Gellerich, Norbert F; Holtz, Juergen

    2005-03-01

    During chemotherapy with anthracyclines, attenuated neuregulin signaling by the erbB2 receptor inactivating antibody Trastuzumab enhances the heart failure risk. We compared the effects of attenuated neuregulin/erbB signaling and of daunorubicin on splicing of the Bcl-x gene and on mitochondrial activation of apoptosis in cardiomyocytes. Attenuating erbB signals in cultured neonatal rat cardiomyocytes by the erbB2 antagonist tyrphostin AG825, by the erbB1/4 antagonist AG1478 or by antisense-induced lowering of erbB2 receptors resulted in an augmented Bcl-xS/Bcl-xL ratio, mitochondrial release of cytochrome c, activation of caspase 9 and caspase 3, and nucleosome-sized DNA fragmentation. A similar DNA fragmentation and caspase 3 activation was induced by TNF-alpha, but without Bcl-xS/Bcl-xL increase, cytochrome c release or caspase 9 activation. A BH4-domain containing HIV TAT fusion protein added to cardiomyocytes under attenuated erbB signaling lowered the enhanced Bcl-xS/Bcl-xL ratio, the cytochrome c release, the caspase 3 activation and the DNA fragmentation, while apoptosis was not modified by the fusion protein in TNF-alpha treated cardiomyocytes. Enhancement of Bcl-xS/Bcl-xL by reducing Bcl-xL via siRNA transfection mimicked the mitochondrial apoptotic activation due to erbB signal attenuation. Daunorubicin also caused Bcl-xS/Bcl-xL enhancement and mitochondrial apoptotic activation in cultured cardiomyocytes; this was attenuated by BH4-fusion protein or by neuregulin-1 and augmented by siRNA-mediated Bcl-xL lowering. We conclude that activation of mitochondrial apoptosis due to altered Bcl-x splicing contributes as a common mechanism of anthracyclines and erbB signal attenuation to the enhanced heart failure risk under this combination.

  20. Diospyrin derivative, an anticancer quinonoid, regulates apoptosis at endoplasmic reticulum as well as mitochondria by modulating cytosolic calcium in human breast carcinoma cells

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Binod [Department of Pharmaceutical Technology, Jadavpur University, Kolkata 700032 (India); Radiation and Cancer Biology Section, Radiation Biology and Health Sciences Division, Bhabha Atomic Research Centre, Mumbai 400085 (India); Kumar, Amit [Radiation and Cancer Biology Section, Radiation Biology and Health Sciences Division, Bhabha Atomic Research Centre, Mumbai 400085 (India); Ghosh, Subhalakshmi [Department of Pharmaceutical Technology, Jadavpur University, Kolkata 700032 (India); Pandey, Badri N., E-mail: bnp@barc.gov.in [Radiation and Cancer Biology Section, Radiation Biology and Health Sciences Division, Bhabha Atomic Research Centre, Mumbai 400085 (India); Mishra, Kaushala P. [Radiation and Cancer Biology Section, Radiation Biology and Health Sciences Division, Bhabha Atomic Research Centre, Mumbai 400085 (India); Hazra, Banasri, E-mail: banasrihazra@yahoo.co.in [Department of Pharmaceutical Technology, Jadavpur University, Kolkata 700032 (India)

    2012-01-13

    Highlights: Black-Right-Pointing-Pointer Diospyrin diethylether (D7) caused oxidative stress-dependent activation of PC-PLC. Black-Right-Pointing-Pointer Activated PC-PLC induced a sustained-release of Ca{sup 2+} from endoplasmic reticulum. Black-Right-Pointing-Pointer The elevated cytosolic Ca{sup +2} led to the calpain-caspase12 dependent apoptosis. Black-Right-Pointing-Pointer D7-Induced Ca{sup +2} also found to accentuate the mitochondrial pathway of apoptosis. -- Abstract: Diospyrin diethylether (D7), a bisnaphthoquinonoid derivative, exhibited an oxidative stress-dependent apoptosis in several human cancer cells and tumor models. The present study was aimed at evaluation of the increase in cytosolic calcium [Ca{sup 2+}]{sub c} leading to the apoptotic cell death triggered by D7 in MCF7 human breast carcinoma cells. A phosphotidylcholine-specific phospholipase C (PC-PLC) inhibitor, viz. U73122, and an antioxidant, viz. N-acetylcysteine, could significantly prevent the D7-induced rise in [Ca{sup 2+}]{sub c} and PC-PLC activity. Using an endoplasmic reticulum (ER)-Ca{sup 2+} mobilizer (thapsigargin) and an ER-IP3R antagonist (heparin), results revealed ER as a major source of [Ca{sup 2+}]{sub c} which led to the activation of calpain and caspase12, and cleavage of fodrin. These effects including apoptosis were significantly inhibited by the pretreatment of Bapta-AM (a cell permeable Ca{sup 2+}-specific chelator), or calpeptin (a calpain inhibitor). Furthermore, D7-induced [Ca{sup 2+}]{sub c} was found to alter mitochondrial membrane potential and induce cytochrome c release, which was inhibited by either Bapta-AM or ruthenium red (an inhibitor of mitochondrial Ca{sup 2+} uniporter). Thus, these results provided a deeper insight into the D7-induced redox signaling which eventually integrated the calcium-dependent calpain/caspase12 activation and mitochondrial alterations to accentuate the induction of apoptotic cell death.

  1. Phorbol esters from Jatropha meal triggered apoptosis, activated PKC-δ, caspase-3 proteins and down-regulated the proto-oncogenes in MCF-7 and HeLa cancer cell lines.

    Science.gov (United States)

    Oskoueian, Ehsan; Abdullah, Norhani; Ahmad, Syahida

    2012-01-01

    Jatropha meal produced from the kernel of Jatropha curcas Linn. grown in Malaysia contains phorbol esters (PEs). The potential benefits of PEs present in the meal as anticancer agent are still not well understood. Hence, this study was conducted to evaluate the cytotoxic effects and mode of actions of PEs isolated from Jatropha meal against breast (MCF-7) and cervical (HeLa) cancer cell lines. Isolated PEs inhibited cells proliferation in a dose-dependent manner of both MCF-7 and HeLa cell lines with the IC₅₀ of 128.6 ± 2.51 and 133.0 ± 1.96 µg PMA equivalents/mL respectively, while the values for the phorbol 12-myristate 13-acetate (PMA) as positive control were 114.7 ± 1.73 and 119.6 ± 3.73 µg/mL, respectively. Microscopic examination showed significant morphological changes that resemble apoptosis in both cell lines when treated with PEs and PMA at IC₅₀ concentration after 24 h. Flow cytometry analysis and DNA fragmentation results confirmed the apoptosis induction of PEs and PMA in both cell lines. The PEs isolated from Jatropha meal activated the PKC-δ and down-regulated the proto-oncogenes (c-Myc, c-Fos and c-Jun). These changes probably led to the activation of Caspase-3 protein and apoptosis cell death occurred in MCF-7 and HeLa cell lines upon 24 h treatment with PEs and PMA. Phorbol esters of Jatropha meal were found to be promising as an alternative to replace the chemotherapeutic drugs for cancer therapy. PMID:22964499

  2. Phorbol Esters from Jatropha Meal Triggered Apoptosis, Activated PKC-δ, Caspase-3 Proteins and Down-Regulated the Proto-Oncogenes in MCF-7 and HeLa Cancer Cell Lines

    Directory of Open Access Journals (Sweden)

    Syahida Ahmad

    2012-09-01

    Full Text Available Jatropha meal produced from the kernel of Jatropha curcas Linn. grown in Malaysia contains phorbol esters (PEs. The potential benefits of PEs present in the meal as anticancer agent are still not well understood. Hence, this study was conducted to evaluate the cytotoxic effects and mode of actions of PEs isolated from Jatropha meal against breast (MCF-7 and cervical (HeLa cancer cell lines. Isolated PEs inhibited cells proliferation in a dose-dependent manner of both MCF-7 and HeLa cell lines with the IC50 of 128.6 ± 2.51 and 133.0 ± 1.96 µg PMA equivalents/mL respectively, while the values for the phorbol 12-myristate 13-acetate (PMA as positive control were 114.7 ± 1.73 and 119.6 ± 3.73 µg/mL, respectively. Microscopic examination showed significant morphological changes that resemble apoptosis in both cell lines when treated with PEs and PMA at IC50 concentration after 24 h. Flow cytometry analysis and DNA fragmentation results confirmed the apoptosis induction of PEs and PMA in both cell lines. The PEs isolated from Jatropha meal activated the PKC-δ and down-regulated the proto-oncogenes (c-Myc, c-Fos and c-Jun. These changes probably led to the activation of Caspase-3 protein and apoptosis cell death occurred in MCF-7 and HeLa cell lines upon 24 h treatment with PEs and PMA. Phorbol esters of Jatropha meal were found to be promising as an alternative to replace the chemotherapeutic drugs for cancer therapy.

  3. Phorbol esters from Jatropha meal triggered apoptosis, activated PKC-δ, caspase-3 proteins and down-regulated the proto-oncogenes in MCF-7 and HeLa cancer cell lines.

    Science.gov (United States)

    Oskoueian, Ehsan; Abdullah, Norhani; Ahmad, Syahida

    2012-09-10

    Jatropha meal produced from the kernel of Jatropha curcas Linn. grown in Malaysia contains phorbol esters (PEs). The potential benefits of PEs present in the meal as anticancer agent are still not well understood. Hence, this study was conducted to evaluate the cytotoxic effects and mode of actions of PEs isolated from Jatropha meal against breast (MCF-7) and cervical (HeLa) cancer cell lines. Isolated PEs inhibited cells proliferation in a dose-dependent manner of both MCF-7 and HeLa cell lines with the IC₅₀ of 128.6 ± 2.51 and 133.0 ± 1.96 µg PMA equivalents/mL respectively, while the values for the phorbol 12-myristate 13-acetate (PMA) as positive control were 114.7 ± 1.73 and 119.6 ± 3.73 µg/mL, respectively. Microscopic examination showed significant morphological changes that resemble apoptosis in both cell lines when treated with PEs and PMA at IC₅₀ concentration after 24 h. Flow cytometry analysis and DNA fragmentation results confirmed the apoptosis induction of PEs and PMA in both cell lines. The PEs isolated from Jatropha meal activated the PKC-δ and down-regulated the proto-oncogenes (c-Myc, c-Fos and c-Jun). These changes probably led to the activation of Caspase-3 protein and apoptosis cell death occurred in MCF-7 and HeLa cell lines upon 24 h treatment with PEs and PMA. Phorbol esters of Jatropha meal were found to be promising as an alternative to replace the chemotherapeutic drugs for cancer therapy.

  4. Methylselenol, a selenium metabolite, induces cell cycle arrest in G1 phase and apoptosis via the extracellular-regulated kinase 1/2 pathway and other cancer signaling genes.

    Science.gov (United States)

    Zeng, Huawei; Wu, Min; Botnen, James H

    2009-09-01

    Methylselenol has been hypothesized to be a critical selenium (Se) metabolite for anticancer activity in vivo, and our previous study demonstrated that submicromolar methylselenol generated by incubating methionase with seleno-l-methionine inhibits the migration and invasive potential of HT1080 tumor cells. However, little is known about the association between cancer signal pathways and methylselenol's inhibition of tumor cell invasion. In this study, we demonstrated that methylselenol exposure inhibited cell growth and we used a cancer signal pathway-specific array containing 15 different signal transduction pathways involved in oncogenesis to study the effect of methylselenol on cellular signaling. Using real-time RT-PCR, we confirmed that cellular mRNA levels of cyclin-dependent kinase inhibitor 1C (CDKN1C), heme oxygenase 1, platelet/endothelial cell adhesion molecule, and PPARgamma genes were upregulated to 2.8- to 5.7-fold of the control. BCL2-related protein A1, hedgehog interacting protein, and p53 target zinc finger protein genes were downregulated to 26-52% of the control, because of methylselenol exposure. These genes are directly related to the regulation of cell cycle and apoptosis. Methylselenol increased apoptotic cells up to 3.4-fold of the control and inhibited the extracellular-regulated kinase 1/2 (ERK1/2) signaling and cellular myelocytomatosis oncogene (c-Myc) expression. Taken together, our studies identify 7 novel methylselenol responsive genes and demonstrate that methylselenol inhibits ERK1/2 pathway activation and c-Myc expression. The regulation of these genes is likely to play a key role in G1 cell cycle arrest and apoptosis, which may contribute to the inhibition of tumor cell invasion.

  5. Spatial and temporal regulation of collagenases—3,—4,and stromelysin —3 implicates distinct functions in apoptosis and tissue remodeling during frog metamorphosis

    Institute of Scientific and Technical Information of China (English)

    DAMJANOVSKISASHKO; ATSUKOISHIZUYAOKA; 等

    1999-01-01

    Matrix metalloproteinases (MMPs) are a family of extracellular proteases capable of degrading various proteinaceous components of the extracellular matrix(ECM).They have been implicated to play important roles in a number of developmental and pathological processes,such as tumor metastasis and inflammation.Relatively few studies have been carried out to investigate the function of MMPs during postembryonic organ-development.Using Xenopus laevis development as a model system,we demonstrate here that three MMPs,stromelysin-3(ST3),collagenases-3(Col3),and Col4,have distinct spatial and temporal expression profiles during metamorphosis as the tadpole transforms into a frog.In situ hybridizations reveal a tight,but distinct,association of individual MMPs with tissue remodeling in the tail and intestine during metamorphosis.In particular,ST3 expression is strongly correlated with apoptosis in both organs as demonstrated by analyses of serial sections with in situ hybridization for ST3 mRNA and TUNEL (terminal deoxyribonucleotidyl transferase-mediated dUTP-biotin nick end labeling)for apoptosis,respectively.On the other hand,Col3 and Col4 are present in regions where extensive connective tissue remodeling take place.These results indicate that ST3 is likely to play a role in ECM-remodeling that facilitate apoptotic tissue remodeling or resorption while Col3 and Col4 appear to participate in connective tissue degradation during development.

  6. CCK、Gastrin对胆管癌细胞凋亡的调控%The Regulating Effect of CCK and Gastrin on Apoptosis of Bile Duct Carcinoma Cells

    Institute of Scientific and Technical Information of China (English)

    马宽生; 张丰深; 何振平; 董家鸿

    2002-01-01

    目的探讨CCK、Gastrin对胆管癌细胞凋亡的影响及其机理.方法以beauvericin为凋亡诱导剂,应用TUNEL荧光染色、流式细胞仪检测和反义bcl-2寡核苷酸技术初步探讨了CCK、Gastrin对胆管癌细胞凋亡阈值的影响,及用免疫组化、原位杂交、流式细胞术、RT-PCR等技术,研究了凋亡相关基因bcl-2和bax在其中的作用.结果发现beauvericin40μM、作用12h,QBC939胆管癌细胞的存活率降低35%~40%,80%左右的胆管癌细胞出现不同程度的凋亡;CCK、Gastrin对胆管癌细胞凋亡阈值有上调作用;CCK/Gastrin受体拈抗剂L60和L18及反义bcl-2寡核苷酸可抑制它们的作用.CCK、Gastrin在转录和翻译水平对bcl-2基因表达均有显著的促进作用,而对bax基因无明显影响;CCK-A受体或CCK-B/Gastrin受体拮抗剂则明显抑制Gastrin-17和CCK-8S对bcl-2基因的促表达作用.结论CCK和Gastrin通过对bcl-2基因表达的上调,抑制了胆管癌细胞的凋亡.本研究在理论上扩展了CCK/Gastrin对肿瘤生长调控的机理、丰富了消化道肿瘤凋亡调控的机制,也为胆管癌的辅助治疗提供了新的思路.%Objective Probe into the influence and the mechanisms of CCK and gastrin on the apoptosis of bile duct carcinoma cells.Methods By taking beauvericin as the revulsant to the apoptosis of bile duct carcinoma cells, the influence of CCK and gastrin on theapoptosis of bile duct carcinoma cells was investigated by using the techniques such as TUNEL fluorescent staining, stream mode cell de-tecting instrument and reverse bcl-2 oligonucleotide. Techniques of immunohistochemistry, in situ hybridization, flow cytometry (FCM),RT-PCR were used to study the roles of apoptosis-related genes bcl-2 and baxResults After beauvericin 40μM worked for 12 h, the survival rate of QBC939 bile duct carcinoma cells was decreased by 35% - 40%.About 80% of the bile duct carcinoma cells showed various degrees of apoptosis. CCK and gastrin could

  7. Flavokawain C Inhibits Cell Cycle and Promotes Apoptosis, Associated with Endoplasmic Reticulum Stress and Regulation of MAPKs and Akt Signaling Pathways in HCT 116 Human Colon Carcinoma Cells.

    Directory of Open Access Journals (Sweden)

    Chung-Weng Phang

    Full Text Available Flavokawain C (FKC is a naturally occurring chalcone which can be found in Kava (Piper methysticum Forst root. The present study evaluated the effect of FKC on the growth of various human cancer cell lines and the underlying associated mechanisms. FKC showed higher cytotoxic activity against HCT 116 cells in a time- and dose-dependent manner in comparison to other cell lines (MCF-7, HT-29, A549 and CaSki, with minimal toxicity on normal human colon cells. The apoptosis-inducing capability of FKC on HCT 116 cells was evidenced by cell shrinkage, chromatin condensation, DNA fragmentation and increased phosphatidylserine externalization. FKC was found to disrupt mitochondrial membrane potential, resulting in the release of Smac/DIABLO, AIF and cytochrome c into the cytoplasm. Our results also revealed that FKC induced intrinsic and extrinsic apoptosis via upregulation of the levels of pro-apoptotic proteins (Bak and death receptors (DR5, while downregulation of the levels of anti-apoptotic proteins (XIAP, cIAP-1, c-FlipL, Bcl-xL and survivin, resulting in the activation of caspase-3, -8 and -9 and cleavage of poly(ADP-ribose polymerase (PARP. FKC was also found to cause endoplasmic reticulum (ER stress, as suggested by the elevation of GADD153 protein after FKC treatment. After the cells were exposed to FKC (60μM over 18hrs, there was a substantial increase in the phosphorylation of ERK 1/2. The expression of phosphorylated Akt was also reduced. FKC also caused cell cycle arrest in the S phase in HCT 116 cells in a time- and dose-dependent manner and with accumulation of cells in the sub-G1 phase. This was accompanied by the downregulation of cyclin-dependent kinases (CDK2 and CDK4, consistent with the upregulation of CDK inhibitors (p21Cip1 and p27Kip1, and hypophosphorylation of Rb.

  8. Silver Nanoparticles Biosynthesized Using Achillea biebersteinii Flower Extract: Apoptosis Induction in MCF-7 Cells via Caspase Activation and Regulation of Bax and Bcl-2 Gene Expression

    Directory of Open Access Journals (Sweden)

    Javad Baharara

    2015-02-01

    Full Text Available Silver nanoparticles (Ag-NPs, the most popular nanoparticles, possess unique properties. Achillea biebersteinii is a plant of the Asteraceae family rich in active antitumor components. The aim of this research was the characterization and investigation of the cytotoxic properties of Ag-NPs synthesized using A. biebersteinii flower extract, on a human breast cancer cell line. The Ag-NPs were synthesized after approximately 180 min of reaction at 40 °C, then they were characterized by UV-visible spectroscopy, Fourier transform infrared spectroscopy (FTIR, transmission electron microscopy (TEM and dynamic light scattering (DLS. The anti-apoptosis effect of Ag-NPs on the MCF-7 cell line was investigated by MTT assay, DAPI and acridine orange staining and caspase activity. The transcriptional expression of bax, bcl-2, caspase-3, -8 and -9 were also evaluated by RT-PCR. The TEM images revealed that the Ag-NPs morphology had a different shape. The DLS indicated that the average hydrodynamic diameter of the biosynthesized Ag-NPs was around 12 nm. By UV-visible spectroscopy the strongest absorbance peak was observed at 460 nm. The FTIR results also showed interaction between the plant extract and Ag-NPs due to the similarity in the peak patterns. The EDS results showed that Ag-NPs display an absorption peak at 3 keV, indicating the presence of the element silver. The Ag-NPs caused a dose-dependent decrease in cell viability, fragmentation in nucleic acid, inhibited the proliferation and induction of apoptosis on MCF-7 by suppressing specific cell cycle genes, and simulation programmed cell dead genes. Further investigation is required to establish the potential of this novel and promising approach in cancer therapy.

  9. Retraction: "Down-regulation of Notch-1 and Jagged-1 inhibits prostate cancer cell growth, migration and invasion, and induces apoptosis via inactivation of Akt, mTOR, and NF-κB signaling pathways" by Wang et al.

    Science.gov (United States)

    2016-08-01

    The above article, published online on January 5, 2010 in Wiley Online Library (wileyonlinelibrary.com), has been retracted by agreement between the journal Editor in Chief, Gary S. Stein, and Wiley Periodicals, Inc. The retraction has been agreed following an investigation from Wayne State University involving the first author and the corresponding author that found Figure 5A to be inappropriately manipulated. REFERENCE Wang Z, Li Y, Banerjee S, Kong D, Ahmad A, Nogueira V, Hay N, Sarkar FH. 2010. Down-regulation of Notch-1 and Jagged-1 inhibits prostate cancer cell growth, migration and invasion, and induces apoptosis via inactivation of Akt, mTOR, and NF-κB signaling pathways. J Cell Biochem 109:726-736; doi: 10.1002/jcb.22451.

  10. Retraction: "Down-regulation of Notch-1 is associated with Akt and FoxM1 in inducing cell growth inhibition and apoptosis in prostate cancer cells" by Wang et al.

    Science.gov (United States)

    2016-08-01

    The above article, published online on July 23, 2010 in Wiley Online Library (wileyonlinelibrary.com), has been retracted by agreement between the journal Editor in Chief, Gary S. Stein, and Wiley Periodicals, Inc. The retraction has been agreed following an investigation from Wayne State University involving the first author and the corresponding author that found Figures 1B and 3A to be inappropriately manipulated. REFERENCE Wang Z, Li Y, Ahmad A, Banerjee S, Azmi AS, Kong D, Wojewoda C, Miele L, Sarkar FH. 2011. Down-regulation of Notch-1 is associated with Akt and FoxM1 in inducing cell growth inhibition and apoptosis in prostate cancer cells. J Cell Biochem 112:78-88; doi: 10.1002/jcb.22770.

  11. Retraction: "Down-regulation of Notch-1 and Jagged-1 inhibits prostate cancer cell growth, migration and invasion, and induces apoptosis via inactivation of Akt, mTOR, and NF-κB signaling pathways" by Wang et al.

    Science.gov (United States)

    2016-08-01

    The above article, published online on January 5, 2010 in Wiley Online Library (wileyonlinelibrary.com), has been retracted by agreement between the journal Editor in Chief, Gary S. Stein, and Wiley Periodicals, Inc. The retraction has been agreed following an investigation from Wayne State University involving the first author and the corresponding author that found Figure 5A to be inappropriately manipulated. REFERENCE Wang Z, Li Y, Banerjee S, Kong D, Ahmad A, Nogueira V, Hay N, Sarkar FH. 2010. Down-regulation of Notch-1 and Jagged-1 inhibits prostate cancer cell growth, migration and invasion, and induces apoptosis via inactivation of Akt, mTOR, and NF-κB signaling pathways. J Cell Biochem 109:726-736; doi: 10.1002/jcb.22451. PMID:27301887

  12. Retraction: "Down-regulation of Notch-1 is associated with Akt and FoxM1 in inducing cell growth inhibition and apoptosis in prostate cancer cells" by Wang et al.

    Science.gov (United States)

    2016-08-01

    The above article, published online on July 23, 2010 in Wiley Online Library (wileyonlinelibrary.com), has been retracted by agreement between the journal Editor in Chief, Gary S. Stein, and Wiley Periodicals, Inc. The retraction has been agreed following an investigation from Wayne State University involving the first author and the corresponding author that found Figures 1B and 3A to be inappropriately manipulated. REFERENCE Wang Z, Li Y, Ahmad A, Banerjee S, Azmi AS, Kong D, Wojewoda C, Miele L, Sarkar FH. 2011. Down-regulation of Notch-1 is associated with Akt and FoxM1 in inducing cell growth inhibition and apoptosis in prostate cancer cells. J Cell Biochem 112:78-88; doi: 10.1002/jcb.22770. PMID:27301889

  13. [Protein kinase C activation induces platelet apoptosis].

    Science.gov (United States)

    Zhao, Li-Li; Chen, Meng-Xing; Zhang, Ming-Yi; Dai, Ke-Sheng

    2013-10-01

    Platelet apoptosis elucidated by either physical or chemical compound or platelet storage occurs wildly, which might play important roles in controlling the numbers and functions of circulated platelets, or in the development of some platelet-related diseases. However, up to now, a little is known about the regulatory mechanisms of platelet apoptosis. Protein kinase C (PKC) is highly expressed in platelets and plays central roles in regulating platelet functions. Although there is evidence indicating that PKC is involved in the regulation of apoptosis of nucleated cells, it is still unclear whether PKC plays a role in platelet apoptosis. The aim of this study was to investigate the role of PKC in platelet apoptosis. The effects of PKC on mitochondrial membrane potential (ΔΨm), phosphatidylserine (PS) exposure, and caspase-3 activation of platelets were analyzed by flow cytometry and Western blot. The results showed that the ΔΨm depolarization in platelets was induced by PKC activator in time-dependent manner, and the caspase-3 activation in platelets was induced by PKC in concentration-dependent manner. However, the platelets incubated with PKC inhibitor did not results in ΔΨm depolarization and PS exposure. It is concluded that the PKC activation induces platelet apoptosis through influencing the mitochondrial functions and activating caspase 3. The finds suggest a novel mechanism for PKC in regulating platelet numbers and functions, which has important pathophysiological implications for thrombosis and hemostasis.

  14. Regulatory mechanisms of apoptosis in regularly dividing cells

    Directory of Open Access Journals (Sweden)

    Ribal S Darwish

    2010-08-01

    Full Text Available Ribal S DarwishDepartment of Anesthesiology, Division of Critical Care Medicine, University of Maryland Medical Center, Baltimore, Maryland, USAAbstract: The balance between cell survival and death is essential for normal development and homeostasis of organisms. Apoptosis is a distinct type of cell death with ultrastructural features that are consistent with an active, inherently controlled process. Abnormalities and ­dysregulation of apoptosis contribute to the pathophysiology of multiple disease processes. Apoptosis is strictly regulated by several positive and negative feedback mechanisms that regulate cell death and determine the final outcome after cell exposure to apoptotic stimuli. Mitochondria and caspases are central components of the regulatory mechanisms of ­apoptosis. Recently, noncaspase pathways of apoptosis have been explored through the studies of ­apoptosis-inducing factor and endonuclease G. Multiple difficulties in the apoptosis research relate to apoptosis detection and imaging. This article reviews current understanding of the regulatory mechanisms of apoptosis.Keywords: caspases, apoptosis-inducing factor, apoptosis inhibitory proteins, cytochrome c, mitochondria 

  15. BRCA1 Expression is an Important Biomarker for Chemosensitivity: Suppression of BRCA1 Increases the Apoptosis via Up-regulation of p53 and p21 During Cisplatin Treatment in Ovarian Cancer Cells

    Directory of Open Access Journals (Sweden)

    Ikuo Konishi

    2006-01-01

    Full Text Available BRCA1 is a tumor suppressor which plays a crucial role in the repair of DNA double-strand breaks, and its abnormality is responsible for hereditary ovarian cancer syndrome. It has recently been reported that reduced expression of BRCA1 is also common in sporadic ovarian carcinoma via its promoter hypermethylation, and that ovarian carcinoma patients negative for BRCA1 expression showed favorable prognosis. To address if BRCA1 expression plays a role in the chemotherapeutic response, we analyzed the effect of BRCA1 suppression on the sensitivity to cisplatin and paclitaxel in ovarian cancer cells. Specific siRNA for BRCA1 gene was transfected into 3 ovarian cancer cell lines with various p53 status. Reduced expression of BRCA1 by transfection of BRCA1-siRNA resulted in a 5.3-fold increase in sensitivity to cisplatin in p53-wild A2780 cells, but not in p53-mutated A2780/CDDP and p53-deleted SKOV3 cells. Regarding the sensitivity to paclitaxel, BRCA1 suppression caused no significant changes in all the 3 cell lines. For ionizing radiation sensitivity, BRCA1 suppression also showed a significant higher sensitivity in A2780 cells. Growth curve and cell cycle analyses showed no signifi cant differences between BRCA1-siRNA-transfected A2780 cells and control cells. However, cisplatin treatment under suppression of BRCA1 showed a significantly increased apoptosis along with up-regulation of p53 and p21 in A2780 cells. Accordingly, reduced expression of BRCA1 enhances the cisplatin sensitivity and apoptosis via up-regulation of p53 and p21, but does not affect the paclitaxel sensitivity. Expression of BRCA1 might be an important biomarker for cisplatin resistance in ovarian carcinoma.

  16. Shifting the balance of mitochondrial apoptosis: therapeutic perspectives

    Directory of Open Access Journals (Sweden)

    Simone eFulda

    2012-10-01

    Full Text Available Signaling via the intrinsic (mitochondrial pathway of apoptosis represents one of the critical signal transduction cascades that control the regulation of cell death. This pathway is typically altered in human cancers, thereby providing a suitable target for therapeutic intervention. Members of the Bcl-2 family of proteins as well as cell survival signaling cascades such as the PI3K/Akt/mTOR pathway are involved in the regulation of mitochondria-mediated apoptosis. Therefore, further insights into the molecular mechanisms that form the basis for the control of mitochondria-mediated apoptosis will likely open new perspectives to bypass evasion of apoptosis and treatment resistance in human cancers.

  17. NCTD Promotion of TRAIL-induced Apoptosis in Leukaemia Cells through Up-regulation of DR5%通过上调DR5表达促进TRAIL诱导的白血病细胞凋亡

    Institute of Scientific and Technical Information of China (English)

    李妍; 王长文; 齐玲; 于宏波; 赵文秀; 张铎

    2014-01-01

    为研究去甲斑蝥素(Norcantharidin,NCTD)对白血病细胞的DR5表达及肿瘤坏死因子相关的凋亡诱导配体(TRAIL)诱导凋亡敏感性的影响,通过流式细胞术检测NCTD和rhTRAIL作用下白血病细胞K562的凋亡、DR5表达和细胞内活性氧(reactive oxygen species,ROS)水平;通过免疫印迹技术分析激酶JNK1的表达。结果表明:NCTD以浓度依赖方式上调 DR5表达;与 rhTRAIL单独作用比较,低浓度的 NCTD(7.5μmol/L)与rhTRAIL共同处理可显著提高K562细胞凋亡百分率、ROS水平和JNK1表达。NCTD通过ROS/JNK途径上调DR5表达,增强了白血病细胞对rhTRAIL的敏感性。%To explore the effects of NCTD on DR5 expression and cell apoptosis in leukaemia cells in-duced by TRAIL,apoptosis,expression of DR5 and level of ROS of leukaemia cells K562 induced by NCTD and rhTRAIL were detected using flow cytometry,and protein kinase JNK1 was measured by west-ern blot assay .The results showed that the expression of DR5 was up-regulated by NCTD in a dose-de-pendent model .In contrast to cells induced by rhTRAIL alone,apoptosis rate,ROS and JNK1 in K562 cells treated by rhTRAIL combined with lower concentration of NCTD (7.5μmol/L)were enhanced signif-icantly.In conclusion,NCTD could sensitize leukaemia cells to rhTRAIL by up-regulation of DR5 through ROS/JNK signaling pathway .

  18. Down-regulation of lipid raft-associated onco-proteins via cholesterol-dependent lipid raft internalization in docosahexaenoic acid-induced apoptosis.

    Science.gov (United States)

    Lee, Eun Jeong; Yun, Un-Jung; Koo, Kyung Hee; Sung, Jee Young; Shim, Jaegal; Ye, Sang-Kyu; Hong, Kyeong-Man; Kim, Yong-Nyun

    2014-01-01

    Lipid rafts, plasma membrane microdomains, are important for cell survival signaling and cholesterol is a critical lipid component for lipid raft integrity and function. DHA is known to have poor affinity for cholesterol and it influences lipid rafts. Here, we investigated a mechanism underlying the anti-cancer effects of DHA using a human breast cancer cell line, MDA-MB-231. We found that DHA decreased cell surface levels of lipid rafts via their internalization, which was partially reversed by cholesterol addition. With DHA treatment, caveolin-1, a marker for rafts, and EGFR were colocalized with LAMP-1, a lysosomal marker, in a cholesterol-dependent manner, indicating that DHA induces raft fusion with lysosomes. DHA not only displaced several raft-associated onco-proteins, including EGFR, Hsp90, Akt, and Src, from the rafts but also decreased total levels of those proteins via multiple pathways, including the proteasomal and lysosomal pathways, thereby decreasing their activities. Hsp90 overexpression maintained its client proteins, EGFR and Akt, and attenuated DHA-induced cell death. In addition, overexpression of Akt or constitutively active Akt attenuated DHA-induced apoptosis. All these data indicate that the anti-proliferative effect of DHA is mediated by targeting of lipid rafts via decreasing cell surface lipid rafts by their internalization, thereby decreasing raft-associated onco-proteins via proteasomal and lysosomal pathways and decreasing Hsp90 chaperone function.

  19. Mangrove dolabrane-type of diterpenes tagalsins suppresses tumor growth via ROS-mediated apoptosis and ATM/ATR-Chk1/Chk2-regulated cell cycle arrest.

    Science.gov (United States)

    Neumann, Jennifer; Yang, Yi; Köhler, Rebecca; Giaisi, Marco; Witzens-Harig, Mathias; Liu, Dong; Krammer, Peter H; Lin, Wenhan; Li-Weber, Min

    2015-12-01

    Natural compounds are an important source for drug development. With an increasing cancer rate worldwide there is an urgent quest for new anti-cancer drugs. In this study, we show that a group of dolabrane-type of diterpenes, collectively named tagalsins, isolated from the Chinese mangrove genus Ceriops has potent cytotoxicity on a panel of hematologic cancer cells. Investigation of the molecular mechanisms by which tagalsins kill malignant cells revealed that it induces a ROS-mediated damage of DNA. This event leads to apoptosis induction and blockage of cell cycle progression at S-G2 phase via activation of the ATM/ATR-Chk1/Chk2 check point pathway. We further show that tagalsins suppress growth of human T-cell leukemia xenografts in vivo. Tagalsins show only minor toxicity on healthy cells and are well tolerated by mice. Our study shows a therapeutic potential of tagalsins for the treatment of hematologic malignancies and a new source of anticancer drugs. PMID:26061604

  20. Down-regulation of protein kinase Ceta potentiates the cytotoxic effects of exogenous tumor necrosis factor-related apoptosis-inducing ligand in PC-3 prostate cancer cells.

    Science.gov (United States)

    Sonnemann, Jürgen; Gekeler, Volker; Sagrauske, Antje; Müller, Cornelia; Hofmann, Hans-Peter; Beck, James F

    2004-07-01

    Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a highly promising candidate for the treatment of cancer because it elicits cell death in the majority of tumor cells while sparing most normal cells. Some cancers, however, display resistance to TRAIL, suggesting that treatment with TRAIL alone may be insufficient for cancer therapy. In the present study, we explored whether the apoptotic responsiveness of PC-3 prostate cancer cells to TRAIL could be enhanced by targeting the novel protein kinase C (PKC) isoform eta. Transfection of PC-3 cells with second-generation chimeric antisense oligonucleotides against PKCeta caused a time- and dose-dependent knockdown of PKCeta, as revealed by real-time RT-PCR and Western blot analyses. Knockdown of PKCeta resulted in a marked amplification of TRAIL's cytotoxic activity. Cell killing could be substantially prevented by the pan-caspase inhibitor z-VAD-fmk. In addition, PKCeta knockdown and administration of TRAIL significantly synergized in activation of caspase-3 and internucleosomal DNA fragmentation. Knockdown of PKCeta augmented TRAIL-induced dissipation of the mitochondrial transmembrane potential and release of cytochrome c from mitochondria into the cytosol, indicating that PKCeta acts upstream of mitochondria. We conclude that PKCeta represents a considerable resistance factor with respect to TRAIL and a promising target to exploit the therapeutic potential of TRAIL. PMID:15252138

  1. Apoptosis and Its Significance in Oral Diseases: An Update

    Directory of Open Access Journals (Sweden)

    Megha Jain

    2013-01-01

    Full Text Available Apoptosis is a well defined mode of cell death which plays an imperative role in the development, regulation, and maintenance of the cell populations in multicellular organisms. Apoptosis is implicated in both health and diseases. Errors in apoptotic mechanisms have been allied to a wide range of pathologies including oral diseases. This review presents an update focused on the role and significance of apoptosis in various oral diseases ranging from reactive to benign and malignant pathologies.

  2. [The comeback of mitochondria in Drosophila apoptosis].

    Science.gov (United States)

    Clavier, Amandine; Rincheval-Arnold, Aurore; Mignotte, Bernard; Guénal, Isabelle

    2016-05-01

    The role of the mitochondrion in mammalian cell apoptosis has been established since the mid-1990s. However, the importance of this organelle in non-mammalian apoptosis has long been regarded as minor, notably because of the absence of a crucial role for cytochrome c in caspase activation. Recent results indicate that the control of caspase activation and apoptosis in Drosophila cell death occurs at the mitochondrial level. Numerous proteins that appear key for Drosophila apoptosis regulation constitutively or transiently bind to mitochondria. They participate in the cell death process at different levels such as degradation of an IAP caspase inhibitor, production of mitochondrial reactive oxygen species or stimulation of the mitochondrial fission machinery. The aim of this review is to take stock of these events that might have their counterpart in humans. PMID:27225920

  3. Study of PHI on regulating apoptosis of Burkitt lymphoma Daudi cell line%PHI对Burkitt淋巴瘤Daudi细胞株凋亡调控的实验研究

    Institute of Scientific and Technical Information of China (English)

    洪苓苓; 黄轶群; 马旭东

    2011-01-01

    Objective:To investigate the effect of PHI on Burkitt lymphoma Daudi cell line in vitro and discuss its potential mechanism.Method:The viability of Daudi cells was observed by MTT method.Apoptotic rate was measured by flow cytometry.The expressions of apoptosis associated protein Bcl-2, proCaspase-9, proCaspase-3,McL-1, XIAP and Cyt-C were detected by Western Blot.Result:Compared with untreated cells, PHI inhibited the proliferation and induced the apoptosis of Daudi cells.It inhibited the expression of Bcl-2, McL-1, XIAP, Cyt-C,proCaspase-9, and proCaspase-3.Conclusion: In vitro, PHI could down-regulate the expression of Bcl-2, McL-1,XIAP, Cyt-C, proCaspase-9, and proCaspase-3.PHI might induce the apoptosis through mitochondrion pathway and inhibite the cells growth in Burkitt lymphoma Daudi cell line.PH1 might be a potential new drug for anti Burkitt lymphoma.%目的:研究PHI在体外对伯基特淋巴瘤淋巴瘤Daudi细胞株的作用,观察PHI对诱导淋巴瘤细胞凋亡的影响,初步探讨其可能的机制.方法:用MTT比色法检测体外Daudi细胞在PHI作用后增殖率的变化.用流式细胞术观察PHI诱导Daudi细胞凋亡.用蛋白免疫印迹法(Western Blot)观察在PHI作用下凋亡相关蛋白Bcl-2、proCaspase-9、proCaspase-3、McL-1、XIAP、Cyt-C表达的变化.结果:经PHI处理的Daudi细胞增殖受到明显抑制;PHI可下调Daudi细胞凋亡相关蛋白Bcl-2、McL-1、XIAP、Cyt-C,proCaspase-9、proCaspase-3的表达,诱导Daudi细胞凋亡.结论:PHI抑制伯基特淋巴瘤淋巴瘤细胞凋亡相关蛋白Bcl-2、McL-1、XIAP、Cyt-C、proCaspase-9、proCaspase-3的表达,可能通过影响线粒体凋亡途径促进Daudi细胞凋亡,抑制其细胞增殖,可能是治疗淋巴瘤的潜在新药.

  4. G-protein-coupled Receptor Kinase-interacting Proteins Inhibit Apoptosis by Inositol 1,4,5-Triphosphate Receptor-mediated Ca2+ Signal Regulation*

    OpenAIRE

    Zhang, Songbai; Hisatsune, Chihiro; Matsu-ura, Toru; Mikoshiba, Katsuhiko

    2009-01-01

    The inositol 1,4,5-trisphosphate (IP3) receptor (IP3R) is an intracellular IP3-gated calcium (Ca2+) release channel and plays important roles in regulation of numerous Ca2+-dependent cellular responses. Many intracellular modulators and IP3R-binding proteins regulate the IP3R channel function. Here we identified G-protein-coupled receptor kinase-interacting proteins (GIT), GIT1 and GIT2, as novel IP3R-binding proteins. We found that both GIT1 and GIT2 directly bind to all three subtypes of IP...

  5. 5-alpha-reductase type I (SRD5A1 is up-regulated in non-small cell lung cancer but does not impact proliferation, cell cycle distribution or apoptosis

    Directory of Open Access Journals (Sweden)

    Kapp Friedrich G

    2012-01-01

    Full Text Available Abstract Background Non-small cell lung cancer (NSCLC is one of the most frequent malignancies and has a high mortality rate due to late detection and lack of efficient treatments. Identifying novel drug targets for this indication may open the way for new treatment strategies. Comparison of gene expression profiles of NSCLC and normal adjacent tissue (NAT allowed to determine that 5-alpha-reductase type I (SRD5A1 was up-regulated in NSCLC compared to NAT. This raised the question whether SRD5A1 was involved in sustained proliferation and survival of NSCLC. Methods siRNA-mediated silencing of SRD5A1 was performed in A549 and NCI-H460 lung cancer cell lines in order to determine the impact on proliferation, on distribution during the different phases of the cell cycle, and on apoptosis/necrosis. In addition, lung cancer cell lines were treated with 4-azasteroids, which specifically inhibit SRD5A1 activity, and the effects on proliferation were measured. Statistical analyses using ANOVA and post-hoc Tamhane-T2-test were performed. In the case of non-parametric data, the Kruskal-Wallis test and the post-hoc Mann-Whitney-U-test were used. Results The knock-down of SRDA51 expression was very efficient with the SRD5A1 transcripts being reduced to 10% of control levels. Knock-down efficiency was furthermore confirmed at the protein level. However, no effect of SRD5A1 silencing was observed in the proliferation assay, the cell cycle analysis, and the apoptosis/necrosis assay. Treatment of lung cancer cell lines with 4-azasteroids did not significantly inhibit proliferation. Conclusions In summary, the results suggest that SRD5A1 is not a crucial enzyme for the sustained proliferation of NSCLC cell lines.

  6. 5-Hydroxymethylfurfural protects against ER stress-induced apoptosis in GalN/TNF-α-injured L02 hepatocytes through regulating the PERK-eIF2α signaling pathway.

    Science.gov (United States)

    Jiang, Ze-Qun; Ma, Yan-Xia; Li, Mu-Han; Zhan, Xiu-Qin; Zhang, Xu; Wang, Ming-Yan

    2015-12-01

    5-Hydroxymethylfurfural (5-HMF), a water-soluble compound extracted from wine-processed Fructus corni, is a novel hepatic protectant for treating acute liver injury. The present study was designed to investigate the protective effect of 5-HMF in human L02 hepatocytes injured by D-galactosamine (GalN) and tumor necrosis factor-α (TNF-α) in vitro and to explore the underlying mechanisms of action. Our results showed that 5-HMF caused significant increase in the viability of L02 cells injured by GalN/TNF-α, in accordance with a dose-dependent decrease in apoptotic cell death confirmed by morphological and flow cytometric analyses. Based on immunofluorescence and Western blot assays, we found that GalN/TNF-α induced ER stress in the cells, as indicated by the disturbance of intracellular Ca(2+) concentration, the activation of protein kinase RNA (PKR)-like ER kinase (PERK), phosphorylation of eukaryotic initiation factor 2 alpha (eIF2α), and expression of ATF4 and CHOP proteins, which was reversed by 5-HMF pre-treatment in a dose-dependent manner. The anti-apoptotic effect of 5-HMF was further evidenced by balancing the expression of Bcl-2 family members. In addition, the knockdown of PERK suppressed the expression of phospho-PERK, phospho-eIF2α, ATF4, and CHOP, resulting in a significant decrease in cell apoptosis after the treatment with GalN/TNF-α. 5-HMF could enhance the effects of PERK knockdown, protecting the cells against the GalN/TNF-α insult. In conclusion, these findings demonstrate that 5-HMF can effectively protect GalN/TNF-α-injured L02 hepatocytes against ER stress-induced apoptosis through the regulation of the PERK-eIF2α signaling pathway, suggesting that it is a possible candidate for liver disease therapy. PMID:26721708

  7. KSP inhibitor SB743921 inhibits growth and induces apoptosis of breast cancer cells by regulating p53, Bcl-2, and DTL.

    Science.gov (United States)

    Zhu, Li; Xiao, Fengjun; Yu, Yue; Wang, Hua; Fang, Min; Yang, Yuefeng; Sun, Huiyan; Wang, Lisheng; Sheng, Yuan

    2016-10-01

    Kinesin spindle protein (KSP) is a microtubule-associated motor protein that is specifically expressed by mitosis cells. It is highly expressed in various types of tumors including hematomalignances and solid tumors. Chemical KSP inhibition has become a novel strategy in the development of anticancer drugs. SB743921 is a selective inhibitor for KSP, which is a mitotic protein essential for cell-cycle progression. Although SB743921 has shown antitumor activities for several types of cancers and entered into clinical trials, its therapeutic effects on breast cancer and mechanisms have not been explored. In this study, we tested the antitumor activity of SB743921 in breast cancer cell lines and partly elucidated its mechanisms. KSP and denticleless E3 ubiquitin-protein ligase homolog (DTL) are overexpressed in breast cancer cells compared with no-cancer tissues. Chemical inhibition of KSP by SB743921 not only reduces proliferation but also induces cell-cycle arrest and leads to apoptosis in breast cancer cells. Treatment of MCF-7 and MDA-MB-231 breast cancer cell lines with SB743921 results in decreased ability of colony formation in culture. SB743921 treatment also causes a KSP accumulation in protein level that is associated with cell arrest. Furthermore, we showed that SB743921 treatment significantly reduces the expression of bcl-2 and cell cycle-related protein DTL, and upregulates p53 and caspase-3 in breast cancer cells. Taken together, these data indicated that SB743921 can be expected to be a novel treatment agent for breast cancers. PMID:27379929

  8. KSP inhibitor SB743921 inhibits growth and induces apoptosis of breast cancer cells by regulating p53, Bcl-2, and DTL.

    Science.gov (United States)

    Zhu, Li; Xiao, Fengjun; Yu, Yue; Wang, Hua; Fang, Min; Yang, Yuefeng; Sun, Huiyan; Wang, Lisheng; Sheng, Yuan

    2016-10-01

    Kinesin spindle protein (KSP) is a microtubule-associated motor protein that is specifically expressed by mitosis cells. It is highly expressed in various types of tumors including hematomalignances and solid tumors. Chemical KSP inhibition has become a novel strategy in the development of anticancer drugs. SB743921 is a selective inhibitor for KSP, which is a mitotic protein essential for cell-cycle progression. Although SB743921 has shown antitumor activities for several types of cancers and entered into clinical trials, its therapeutic effects on breast cancer and mechanisms have not been explored. In this study, we tested the antitumor activity of SB743921 in breast cancer cell lines and partly elucidated its mechanisms. KSP and denticleless E3 ubiquitin-protein ligase homolog (DTL) are overexpressed in breast cancer cells compared with no-cancer tissues. Chemical inhibition of KSP by SB743921 not only reduces proliferation but also induces cell-cycle arrest and leads to apoptosis in breast cancer cells. Treatment of MCF-7 and MDA-MB-231 breast cancer cell lines with SB743921 results in decreased ability of colony formation in culture. SB743921 treatment also causes a KSP accumulation in protein level that is associated with cell arrest. Furthermore, we showed that SB743921 treatment significantly reduces the expression of bcl-2 and cell cycle-related protein DTL, and upregulates p53 and caspase-3 in breast cancer cells. Taken together, these data indicated that SB743921 can be expected to be a novel treatment agent for breast cancers.

  9. Apoptosis in the Retina

    OpenAIRE

    Crisanti, Patricia; Lecain, Eric; Omri, Boubaker

    2007-01-01

    Retinal degenerations are a common cause of blindness in Western countries. Despite various origins of retinal degeneration it is well recognised that. Apoptosis is the final pathway of photoreceptor neuron cell death in these diseases. So that Ivana Scovassi presents the historical development of our knowledge in: apoptosis, its difference with other forms of cell death as necrosis and analyses when and how apoptosis arises, discussing also the molecular markers in this form of cell death. T...

  10. Cold-inducible RNA-binding protein inhibits neuron apoptosis through the suppression of mitochondrial apoptosis.

    Science.gov (United States)

    Zhang, Hai-Tao; Xue, Jing-Hui; Zhang, Zhi-Wen; Kong, Hai-Bo; Liu, Ai-Jun; Li, Shou-Chun; Xu, Dong-Gang

    2015-10-01

    Cold-inducible RNA-binding protein (CIRP) is induced by mild hypothermia in several mammals, but the precise mechanism by which CIRP mediates hypothermia-induced neuroprotection remains unknown. We aimed to investigate the molecular mechanisms by which CIRP protects the nervous system during mild hypothermia. Rat cortical neurons were isolated and cultured in vitro under mild hypothermia (32°C). Apoptosis was measured by annexin V and propidium iodide staining, visualized by flow cytometry. Neuron ultrastructure was visualized by transmission electron microscopy. CIRP overexpression and knockdown were achieved via infection with pL/IRES/GFP-CIRP and pL/shRNA/F-CIRP-A lentivirus. RT(2) Profiler PCR Array Pathway Analysis and western blotting were used to evaluate the effects of CIRP overexpresion/knockdown on the neurons׳ transcriptome. Neuron late apoptosis was significantly reduced at day 7 of culture by 12h hypothermia, but neuron ultrastructure remained relatively intact. RT(2) Profiler PCR Array Pathway Analysis of 84 apoptosis pathway-associated factors revealed that mild hypothermia and CIRP overexpression induce similar gene expression profiles, specifically alterations of genes implicated in the mitochondrial apoptosis pathway. Mild hypothermia-treated neurons up-regulated 12 and down-regulated 38 apoptosis pathway-associated genes. CIRP-overexpressing neurons up-regulated 15 and down-regulated 46 genes. CIRP-knocked-down hypothermia-treated cells up-regulated 9 and down-regulated 40 genes. Similar results were obtained at the protein level. In conclusion, CIRP may inhibit neuron apoptosis through the suppression of the mitochondria apoptosis pathway during mild hypothermia.

  11. Bacterial pathogens modulate an apoptosis differentiation program in human neutrophils

    OpenAIRE

    Kobayashi, Scott D.; Braughton, Kevin R.; Whitney, Adeline R.; Voyich, Jovanka M.; Schwan, Tom G.; Musser, James M.; DeLeo, Frank R.

    2003-01-01

    Human polymorphonuclear leukocytes (PMNs or neutrophils) are essential to the innate immune response against bacterial pathogens. Recent evidence suggests that PMN apoptosis facilitates resolution of inflammation during bacterial infection. Although progress has been made toward understanding apoptosis in neutrophils, very little is known about transcriptional regulation of this process during bacterial infection. To gain insight into the molecular processes that facilitate resolution of infe...

  12. Resveratrol induces apoptosis in human esophageal carcinoma cells

    Institute of Scientific and Technical Information of China (English)

    Hai-Bo Zhou; Yun Yan; Ya-Ni Sun; Ju-Ren Zhu

    2003-01-01

    AIM: To investigate the apoptosis in esophageal cancer cells induced by resveratrol, and the relation between this apoptosis and expression of Bcl-2 and Bax.METHODS: In in vitro experiments, MTr assay was used to determine the cell growth inhibitory rate. Transmission electron microscope and TUNEL staining method were used to quantitatively and qualitively detect the apoptosis status of esophageal cancer cell line EC-9706 before and after the resveratrol treatment. Immunohistochemical staining was used to detect the expression of apoptosis-regulated gene Bcl-2 and Bax.RESULTS: Resveratrol inhibited the growth of esophageal cancer cell line EC-9706 in a dose-and time-dependent manner. Resveratrol induced EC-9706 cells to undergo apoptosis with typically apoptotic characteristics, including morphological changes of chromatin condensation, chromatin crescent formation, nucleus fragmentation and apoptotic body formation. TUNEL assay showed that after the for 24 to 96 hours, the AIs were apparently increased with treated time (P<0.05). Immunohistochemical staining showed that after the treatment of EC-9706 cells with proteins were apparently reduced with treated time (P<0.05)and the PRs of Bax proteins were apparently increased with treated time (P<0.05).CONCLUSION: Resveratrol is able to induce the apoptosisin esophageal cancer. This apoptosis may be mediated by down-regulating the apoptosis-regulated gene Bcl-2 and upregulating the expression of apoptosis-regulated gene bax.

  13. Resveratrol and clofarabine induces a preferential apoptosis-activating effect on malignant mesothelioma cells by Mcl-1 down-regulation and caspase-3 activation

    OpenAIRE

    Lee, Yoon-Jin; Lee, Yong-Jin; LEE, SANG-HAN

    2015-01-01

    We previously demonstrated that resveratrol and clofarabine elicited a marked cytotoxicity on malignant mesothelioma (MM) MSTO-211H cells but not on the corresponding normal mesothelial MeT-5A cells. Little is known of the possible molecules that could be used to predict preferential chemosensitivity on MSTO-211H cells. Resveratrol and clofarabine induced down-regulation of Mcl-1 protein level in MSTO-211H cells. Treatment of cells with cycloheximide in the presence of proteasome inhibitor MG...

  14. Apoptosis in Drosophila: which role for mitochondria?

    Science.gov (United States)

    Clavier, Amandine; Rincheval-Arnold, Aurore; Colin, Jessie; Mignotte, Bernard; Guénal, Isabelle

    2016-03-01

    It is now well established that the mitochondrion is a central regulator of mammalian cell apoptosis. However, the importance of this organelle in non-mammalian apoptosis has long been regarded as minor, mainly because of the absence of a crucial role for cytochrome c in caspase activation. Recent results indicate that the control of caspase activation and cell death in Drosophila occurs at the mitochondrial level. Numerous proteins, including RHG proteins and proteins of the Bcl-2 family that are key regulators of Drosophila apoptosis, constitutively or transiently localize in mitochondria. These proteins participate in the cell death process at different levels such as degradation of Diap1, a Drosophila IAP, production of mitochondrial reactive oxygen species or stimulation of the mitochondrial fission machinery. Here, we review these mitochondrial events that might have their counterpart in human. PMID:26679112

  15. Interaction between the Alzheimer's survival peptide humanin and insulin-like growth factor-binding protein 3 regulates cell survival and apoptosis

    OpenAIRE

    Ikonen, Maaria; LIU, BINGRONG; Hashimoto, Yuichi; Ma, Liqun; Lee, Kuk-Wha; Niikura, Takako; Nishimoto, Ikuo; Cohen, Pinchas

    2003-01-01

    Insulin-like growth factor-binding protein-3 (IGFBP-3) regulates IGF bioactivity and also independently modulates cell growth and survival. By using a yeast two-hybrid screen to identify IGFBP-3-interacting proteins, we cloned humanin (HN) as an IGFBP-3-binding partner. HN is a 24-aa peptide that has been shown to specifically inhibit neuronal cell death induced by familial Alzheimer's disease mutant genes and amyloid-β (Aβ). The physical interaction of HN with IGFBP-3 was determined to be of...

  16. Long non-coding RNA TUG1 is up-regulated in hepatocellular carcinoma and promotes cell growth and apoptosis by epigenetically silencing of KLF2

    OpenAIRE

    Huang, Ming-De; Chen, Wen-ming; Qi, Fu-zhen; Sun, Ming; Xu, Tong-peng; Ma, Pei; Shu, Yong-qian

    2015-01-01

    Background Hepatocellular carcinoma (HCC) is one of the leading causes of cancer-related death worldwide, and the biology of this cancer remains poorly understood. Recent evidence indicates that long non-coding RNAs (lncRNAs) are found to be dysregulated in a variety of cancers, including HCC. Taurine Up-regulated Gene 1 (TUG1), a 7.1-kb lncRNA, recruiting and binding to polycomb repressive complex 2 (PRC2), is found to be disregulated in non-small cell lung carcinoma (NSCLC) and esophageal s...

  17. Epithelial Cell Apoptosis and Lung Remodeling

    Institute of Scientific and Technical Information of China (English)

    Kazuyoshi Kuwano

    2007-01-01

    Lung epithelium is the primary site of lung damage in various lung diseases. Epithelial cell apoptosis has been considered to be initial event in various lung diseases. Apoptosis signaling is classically composed of two principle pathways. One is a direct pathway from death receptor ligation to caspase cascade activation and cell death. The other pathway triggered by stresses such as drugs, radiation, infectious agents and reactive oxygen species is mediated by mitochondria. Endoplasmic reticulum has also been shown to be the organelle to mediate apoptosis.Epithelial cell death is followed by remodeling processes, which consist of epithelial and fibroblast activation,cytokine production, activation of coagulation pathway, neoangiogenesis, re-epithelialization and fibrosis.Epithelial and mesenchymal interaction plays important roles in these processes. Further understanding of apoptosis signaling and its regulation by novel strategies may lead to effective treatments against various lung diseases. We review the recent advances in the understanding of apoptosis signaling and discuss the involvement of apoptosis in lung remodeling.

  18. Host-pathogen interactions during apoptosis

    Indian Academy of Sciences (India)

    Seyed E Hasnain; Rasheeda Begum; K V A Ramaiah; Sudhir Sahdev; E M Shajil; Tarvinder K Taneja; Manjari Mohan; M Athar; Nand K Sah; M Krishnaveni

    2003-04-01

    Host pathogen interaction results in a variety of responses, which include phagocytosis of the pathogen, release of cytokines, secretion of toxins, as well as production of reactive oxygen species (ROS). Recent studies have shown that many pathogens exert control on the processes that regulate apoptosis in the host. The induction of apoptosis upon infection results from a complex interaction of parasite proteins with cellular host proteins. Abrogation of host cell apoptosis is often beneficial for the pathogen and results in a successful host invasion. However, in some cases, it has been shown that induction of apoptosis in the infected cells significantly imparts protection to the host from the pathogen. There is a strong correlation between apoptosis and the host protein translation machinery: the pathogen makes all possible efforts to modify this process so as to inhibit cell suicide and ensure that it can survive and, in some cases, establish latent infection. This review discusses the significance of various pathways/steps during virus-mediated modulation of host cell apoptosis.

  19. Linking apoptosis to cancer metabolism: Another missing piece of JuNK

    OpenAIRE

    Papa, S.; Bubici, C

    2016-01-01

    Cancer cells become dependent on aerobic glycolysis to sustain rapid proliferation and escape apoptosis. How this metabolic change, also known as the Warburg effect, is linked to apoptosis remains largely unknown. Our new data place c-Jun N-terminal kinase in the center of a hub regulating apoptosis and cancer metabolism.

  20. CDK5 Regulates Paclitaxel Sensitivity in Ovarian Cancer Cells by Modulating AKT Activation, p21Cip1- and p27Kip1-Mediated G1 Cell Cycle Arrest and Apoptosis.

    Directory of Open Access Journals (Sweden)

    Shu Zhang

    Full Text Available Cyclin-dependent kinase 5 (CDK5 is a cytoplasmic serine/ threonine kinase. Knockdown of CDK5 enhances paclitaxel sensitivity in human ovarian cancer cells. This study explores the mechanisms by which CDK5 regulates paclitaxel sensitivity in human ovarian cancers. Multiple ovarian cancer cell lines and xenografts were treated with CDK5 small interfering RNA (siRNA with or without paclitaxel to examine the effect on cancer cell viability, cell cycle arrest and tumor growth. CDK5 protein was measured by immunohistochemical staining of an ovarian cancer tissue microarray to correlate CDK5 expression with overall patient survival. Knockdown of CDK5 with siRNAs inhibits activation of AKT which significantly correlates with decreased cell growth and enhanced paclitaxel sensitivity in ovarian cancer cell lines. In addition, CDK5 knockdown alone and in combination with paclitaxel induced G1 cell cycle arrest and caspase 3 dependent apoptotic cell death associated with post-translational upregulation and nuclear translocation of TP53 and p27(Kip1 as well as TP53-dependent transcriptional induction of p21(Cip1 in wild type TP53 cancer cells. Treatment of HEYA8 and A2780 wild type TP53 xenografts in nu/nu mice with CDK5 siRNA and paclitaxel produced significantly greater growth inhibition than either treatment alone. Increased expression of CDK5 in human ovarian cancers correlates inversely with overall survival. CDK5 modulates paclitaxel sensitivity by regulating AKT activation, the cell cycle and caspase-dependent apoptosis. CDK5 inhibition can potentiate paclitaxel activity in human ovarian cancer cells.

  1. CDK5 Regulates Paclitaxel Sensitivity in Ovarian Cancer Cells by Modulating AKT Activation, p21Cip1- and p27Kip1-Mediated G1 Cell Cycle Arrest and Apoptosis.

    Science.gov (United States)

    Zhang, Shu; Lu, Zhen; Mao, Weiqun; Ahmed, Ahmed A; Yang, Hailing; Zhou, Jinhua; Jennings, Nicholas; Rodriguez-Aguayo, Cristian; Lopez-Berestein, Gabriel; Miranda, Roberto; Qiao, Wei; Baladandayuthapani, Veera; Li, Zongfang; Sood, Anil K; Liu, Jinsong; Le, Xiao-Feng; Bast, Robert C

    2015-01-01

    Cyclin-dependent kinase 5 (CDK5) is a cytoplasmic serine/ threonine kinase. Knockdown of CDK5 enhances paclitaxel sensitivity in human ovarian cancer cells. This study explores the mechanisms by which CDK5 regulates paclitaxel sensitivity in human ovarian cancers. Multiple ovarian cancer cell lines and xenografts were treated with CDK5 small interfering RNA (siRNA) with or without paclitaxel to examine the effect on cancer cell viability, cell cycle arrest and tumor growth. CDK5 protein was measured by immunohistochemical staining of an ovarian cancer tissue microarray to correlate CDK5 expression with overall patient survival. Knockdown of CDK5 with siRNAs inhibits activation of AKT which significantly correlates with decreased cell growth and enhanced paclitaxel sensitivity in ovarian cancer cell lines. In addition, CDK5 knockdown alone and in combination with paclitaxel induced G1 cell cycle arrest and caspase 3 dependent apoptotic cell death associated with post-translational upregulation and nuclear translocation of TP53 and p27(Kip1) as well as TP53-dependent transcriptional induction of p21(Cip1) in wild type TP53 cancer cells. Treatment of HEYA8 and A2780 wild type TP53 xenografts in nu/nu mice with CDK5 siRNA and paclitaxel produced significantly greater growth inhibition than either treatment alone. Increased expression of CDK5 in human ovarian cancers correlates inversely with overall survival. CDK5 modulates paclitaxel sensitivity by regulating AKT activation, the cell cycle and caspase-dependent apoptosis. CDK5 inhibition can potentiate paclitaxel activity in human ovarian cancer cells. PMID:26146988

  2. ICAM-1 and AMPK regulate cell detachment and apoptosis by N-methyl-N Prime -nitro-N-nitrosoguanidine, a widely spread environmental chemical, in human hormone-refractory prostate cancers

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Yi-Cheng; Lu, Pin-Hsuan; Hsu, Jui-Ling; Yu, Chia-Chun; Guh, Jih-Hwa, E-mail: jhguh@ntu.edu.tw

    2011-12-15

    Poly(ADP-ribose) polymerase-1 (PARP-1), a sensor of DNA damage, plays a crucial role in the regulation of DNA repair. PARP-1 hyperactivation causes DNA damage and cell death. The underlying mechanism is complicated and is through diverse pathways. The understanding of responsible signaling pathways may offer implications for effective therapies. After concentration-response determination of N-Methyl-N Prime -Nitro-N-Nitrosoguanidine (MNNG, a PARP-1 activating agent and an environmental mutagen) in human hormone-refractory prostate cancers, the data showed that concentrations below 5 {mu}M did not change cell survival but cause a time-dependent up-regulation of intracellular adhesion molecule-1 (ICAM-1) in mRNA, total protein and cell surface levels. Detection of phosphorylation and degradation of I{kappa}B-{alpha} and nuclear translocation of NF-{kappa}B showed that MNNG induced the activation of NF-{kappa}B that was responsible for the ICAM-1 up-regulation since PDTC (a NF-{kappa}B inhibitor) significantly abolished this effect. However, higher concentrations (e.g., 10 {mu}M) of MNNG induced a 61% detachment of the cells which were apoptosis associated with the activation of AMP-activated protein kinase (AMPK), c-Jun N-terminal kinase (JNK) and p38 mitogen-activated protein kinase (MAPK). Further identification showed that both AMPK and JNK other than p38 MAPK functionally contributed to cell death. The remaining 39% attached cells were survival associated with high ICAM-1 expression. In conclusion, the data suggest that NF-{kappa}B-dependent up-regulation of ICAM-1 plays a key role on cell attachment and survival; whereas, activation of AMPK and JNK participates in cytotoxic signaling pathways in detached cells caused by PARP-1 activation. Highlights: Black-Right-Pointing-Pointer Low level of DNA damage helps cell attachment and survival via ICAM-1 upregulation. Black-Right-Pointing-Pointer High level of DNA damage causes AMPK- and JNK-involved cell detachment

  3. Characterization of two regulators of the TNF-α signaling pathway in Apostichopus japonicus: LPS-induced TNF-α factor and baculoviral inhibitor of apoptosis repeat-containing 2.

    Science.gov (United States)

    Zhang, Xiumei; Zhang, Pengjuan; Li, Chenghua; Li, Ye; Jin, Chunhua; Zhang, Weiwei

    2015-01-01

    The TNF-α signaling cascade is involved in the regulation of a variety of biological processes, including cell proliferation, differentiation, apoptosis and the immune response in vertebrates. Here, two regulatory genes, lipopolysaccharide-induced tumor necrosis factor α factor (LITAF) and baculoviral inhibitor of apoptosis repeat-containing 2 (BIRC2), were identified in coelomocytes from the sea cucumber Apostichopus japonicus by RNA-seq and RACE (denoted as AjLITAF and AjBIRC2, respectively). The full-length cDNA of AjLITAF was 1417 bp, with a 5' untranslated region (UTR) of 189 bp, a 3' UTR of 637 bp with one cytokine RNA instability motif (ATTTA) and an open reading frame (ORF) of 591 bp encoding a polypeptide of 196 amino acid residues and a predicted molecular weight of 22.1 kDa. The partial AjBIRC2 cDNA was 2324 bp with a 5' UTR of 145 bp, a 3' UTR of 469 bp and a complete ORF of 1710 bp encoding a polypeptide of 569 amino acid residues. Analysis of the deduced amino acid sequences revealed that both genes shared a remarkably high degree of structural conservation with their mammalian orthologs, including a highly conserved LITAF domain in AjLITAF and three types of BIR domains in AjBIRC2. Spatial expression analysis revealed that AjLITAF and AjBIRC2 were expressed at a slightly lower level in the intestine and tentacle tissues compared with the other four tissues examined. After challenging the sea cucumbers with Vibrio splendidus, the expression levels of AjLITAF and AjBIRC2 in coelomocytes were increased by 2.65-fold at 6 h and 1.76-fold at 24 h compared with the control group. In primary cultured coelomocytes, a significant increase in the expression of AjLITAF and AjBIRC2 was detected after 6 h of exposure to 1 µg mL(-1) LPS. Together, these results suggest that AjLITAF and AjBIRC2 might be involved in the sea cucumber immune response during the course of a pathogenic infection or exposure to pathogen-associated molecular

  4. TRAF2 regulates TNF and NF-κB signalling to suppress apoptosis and skin inflammation independently of Sphingosine kinase 1.

    Science.gov (United States)

    Etemadi, Nima; Chopin, Michael; Anderton, Holly; Tanzer, Maria C; Rickard, James A; Abeysekera, Waruni; Hall, Cathrine; Spall, Sukhdeep K; Wang, Bing; Xiong, Yuquan; Hla, Timothy; Pitson, Stuart M; Bonder, Claudine S; Wong, Wendy Wei-Lynn; Ernst, Matthias; Smyth, Gordon K; Vaux, David L; Nutt, Stephen L; Nachbur, Ueli; Silke, John

    2015-01-01

    TRAF2 is a component of TNF superfamily signalling complexes and plays an essential role in the regulation and homeostasis of immune cells. TRAF2 deficient mice die around birth, therefore its role in adult tissues is not well-explored. Furthermore, the role of the TRAF2 RING is controversial. It has been claimed that the atypical TRAF2 RING cannot function as a ubiquitin E3 ligase but counterclaimed that TRAF2 RING requires a co-factor, sphingosine-1-phosphate, that is generated by the enzyme sphingosine kinase 1, to function as an E3 ligase. Keratinocyte-specific deletion of Traf2, but not Sphk1 deficiency, disrupted TNF mediated NF-κB and MAP kinase signalling and caused epidermal hyperplasia and psoriatic skin inflammation. This inflammation was driven by TNF, cell death, non-canonical NF-κB and the adaptive immune system, and might therefore represent a clinically relevant model of psoriasis. TRAF2 therefore has essential tissue specific functions that do not overlap with those of Sphk1.

  5. TRAF2 regulates TNF and NF-κB signalling to suppress apoptosis and skin inflammation independently of Sphingosine kinase 1

    Science.gov (United States)

    Etemadi, Nima; Chopin, Michael; Anderton, Holly; Tanzer, Maria C; Rickard, James A; Abeysekera, Waruni; Hall, Cathrine; Spall, Sukhdeep K; Wang, Bing; Xiong, Yuquan; Hla, Timothy; Pitson, Stuart M; Bonder, Claudine S; Wong, Wendy Wei-Lynn; Ernst, Matthias; Smyth, Gordon K; Vaux, David L; Nutt, Stephen L; Nachbur, Ueli; Silke, John

    2015-01-01

    TRAF2 is a component of TNF superfamily signalling complexes and plays an essential role in the regulation and homeostasis of immune cells. TRAF2 deficient mice die around birth, therefore its role in adult tissues is not well-explored. Furthermore, the role of the TRAF2 RING is controversial. It has been claimed that the atypical TRAF2 RING cannot function as a ubiquitin E3 ligase but counterclaimed that TRAF2 RING requires a co-factor, sphingosine-1-phosphate, that is generated by the enzyme sphingosine kinase 1, to function as an E3 ligase. Keratinocyte-specific deletion of Traf2, but not Sphk1 deficiency, disrupted TNF mediated NF-κB and MAP kinase signalling and caused epidermal hyperplasia and psoriatic skin inflammation. This inflammation was driven by TNF, cell death, non-canonical NF-κB and the adaptive immune system, and might therefore represent a clinically relevant model of psoriasis. TRAF2 therefore has essential tissue specific functions that do not overlap with those of Sphk1. DOI: http://dx.doi.org/10.7554/eLife.10592.001 PMID:26701909

  6. Apoptosis signal-regulating kinase 1 is involved in brain-derived neurotrophic factor (BDNF)-enhanced cell motility and matrix metalloproteinase 1 expression in human chondrosarcoma cells.

    Science.gov (United States)

    Lin, Chih-Yang; Chang, Sunny Li-Yun; Fong, Yi-Chin; Hsu, Chin-Jung; Tang, Chih-Hsin

    2013-07-25

    Chondrosarcoma is the primary malignancy of bone that is characterized by a potent capacity to invade locally and cause distant metastasis, and is therefore associated with poor prognoses. Chondrosarcoma further shows a predilection for metastasis to the lungs. The brain-derived neurotrophic factor (BDNF) is a small molecule in the neurotrophin family of growth factors that is associated with the disease status and outcome of cancers. However, the effect of BDNF on cell motility in human chondrosarcoma cells is mostly unknown. Here, we found that human chondrosarcoma cell lines had significantly higher cell motility and BDNF expression compared to normal chondrocytes. We also found that BDNF increased cell motility and expression of matrix metalloproteinase-1 (MMP-1) in human chondrosarcoma cells. BDNF-mediated cell motility and MMP-1 up-regulation were attenuated by Trk inhibitor (K252a), ASK1 inhibitor (thioredoxin), JNK inhibitor (SP600125), and p38 inhibitor (SB203580). Furthermore, BDNF also promoted Sp1 activation. Our results indicate that BDNF enhances the migration and invasion activity of chondrosarcoma cells by increasing MMP-1 expression through a signal transduction pathway that involves the TrkB receptor, ASK1, JNK/p38, and Sp1. BDNF thus represents a promising new target for treating chondrosarcoma metastasis.

  7. Trace elements and apoptosis

    Energy Technology Data Exchange (ETDEWEB)

    Koudrine, A.V. [Orenburg State Medical Academy, Orenburg (Russian Federation)

    1998-07-01

    It is known that apoptosis is considered to be responsible for selective deletion of cells during embryogenesis, the homeostasis of cell populations in continuously renewing tissues (i.e., serving as a counterbalance to mitosis), and tissue involution in response to chemical or physical stimuli. There are many publications on these questions. On the other hand, the intracellular processes that contribute to apoptosis are incompletely understood. Therefore, the role of apoptosis in the intracellular accumulation and outflow of minerals is of considerable importance in light of both their essential functions and toxic effects. (orig.)

  8. DNA fragmentation in apoptosis

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Cleavage of chromosomal DNA into oligonucleosomal size fragments is an integral part of apoptosis. Elegant biochemical work identified the DNA fragmentation factor (DFF) as a major apoptotic endonuclease for DNA fragmentation in vitro. Genetic studies in mice support the importance of DFF in DNA fragmentation and possibly in apoptosis in vivo. Recent work also suggests the existence of additional endonucleases for DNA degradation. Understanding the roles of individual endonucleases in apoptosis, and how they might coordinate to degrade DNA in different tissues during normal development and homeostasis, as well as in various diseased states, will be a major research focus in the near future.

  9. Apoptosis inhibitor of macrophage (AIM) expression in alveolar macrophages in COPD

    OpenAIRE

    Kojima, Jun; Araya, Jun; Hara, Hiromichi; Ito, Saburo; Takasaka, Naoki; Kobayashi, Kenji; Fujii, Satoko; Tsurushige, Chikako; Numata, Takanori; Ishikawa, Takeo; Shimizu, Kenichiro; Kawaishi, Makoto; Saito, Keisuke; Kamiya, Noriki; Hirano, Jun

    2013-01-01

    Background Marked accumulation of alveolar macrophages (AM) conferred by apoptosis resistance has been implicated in pathogenesis of chronic obstructive pulmonary disease (COPD). Apoptosis inhibitor of macrophage (AIM), has been shown to be produced by mature tissue macrophages and AIM demonstrates anti-apoptotic property against multiple apoptosis-inducing stimuli. Accordingly, we attempt to determine if AIM is expressed in AM and whether AIM is involved in the regulation of apoptosis in the...

  10. 钩藤生物碱调节肠系膜动脉细胞增殖凋亡相关蛋白的研究%Regulation effect of uncaria alkaloids on proliferation apoptosis related protein of mesenteric arterial cells

    Institute of Scientific and Technical Information of China (English)

    焦华琛; 李运伦; 孙敬昌

    2013-01-01

    Objective:To study the apoptosis and proliferation effect of rhynchophylline,isorhynchophylline and uncaria alkaloids on spontaneously hypertensive rat(SHR) mesenteric artery smooth muscle cells. Methods:SHR were divided into different groups, and given rhynchophylline, isorhynchophylline and uncaria alkaloids. Wistar rats were used as normal control. Mesenteric artery pathology was observed by HE staining, mesenteric artery collagen content by Masson staining. Bcl-2, Bax, c-myc, c-fos, MMP-9 and TIMP-2 protein expression of mesenteric artery were detected by immunohistochemical. Results: Rhynchophylline, isorhynchophylline and uncaria alkaloids could alleviate the pathological damage of the SHR mesenteric arteries, reduce arterial wall collagen deposition,and lower the protein expression of Bcl-2,c-fos and TIMP-2 of mesenteric artery smooth muscle. Rhynchophylline increased mesenteric artery MMP-9 protein expression. Conclusion: Rhynchophylline and isorhynchophylline may promote apoptosis of SHR mesenteric arteries by lowering the proto-oncogene Bcl-2 protein expression, inhibite mesenteric artery cells abnormal proliferation by down-regulating c-fos protein expression pathway,and inhibite collagen deposition through regulating MMP-9 and TIMP-2 protein expression. Thereby the mesenteric arterial walls were improved.%目的:研究钩藤碱、异钩藤碱和钩藤总生物碱对自发性高血压大鼠(SHR)肠系膜动脉平滑肌细胞凋亡和增殖的影响.方法:将SHR分组,分别给予钩藤碱、异钩藤碱和钩藤总生物碱,并以Wistar大鼠作为正常对照.采用HE染色法观测肠系膜动脉的病理形态,采用Masson染色法观察肠系膜动脉胶原含量,采用免疫组化法检测肠系膜动脉Bcl-2、Bax、c-myc、c-fos、MMP-9和TIMP-2的蛋白表达.结果:钩藤碱、异钩藤碱和钩藤总生物碱能减轻SHR肠系膜动脉的病理损害,降低动脉壁的胶原沉积,下调肠系膜动脉平滑肌Bcl-2、c-fos和TIMP-2蛋白表

  11. Baicalin induced dendritic cell apoptosis in vitro

    Directory of Open Access Journals (Sweden)

    Huahua eZhang

    2011-03-01

    Full Text Available This study was aimed to investigate the effects of Baicalin (BA, a major flavonoid constituent found in the herb Baikal skullcap, on dendritic cells (DCs. DCs were generated by culturing murine bone marrow cells for 6 days with granulocyte-macrophage colony-stimulating factor and interleukin-4, and lipopolysaccharide (LPS was added on day 5 to stimulate DCs maturation. The expression levels of DC maturity markers (CD80/CD86 were assessed by flow cytometry using direct immunofluorescence method. Interleukin-12 (IL-12 levels in the culture supernatants were assayed by ELISA. Apoptosis of DCs was analyzed by flow cytometry after Annexin V/propidium iodide staining. The mitochondrial membrane potential changes were measured by using the J-aggregate forming lipophilic cation 5,5',6,6'-tetrachloro-1,1',3,3'-tetraethylbenzimidazolcarbocyanine iodide (JC-1. Exposure of DCs to BA (2-50 microM during bone marrow cell differentiation showed no effects on the up-regulation of CD80/CD86 expression on DCs in response to LPS stimulation, but reduced DCs recovery by inducing apoptosis, and significantly inhibited the release of IL-12 to culture supernatants. BA induced DC apoptosis in a time- and dose-dependent way, and immature DCs were more sensitive for BA-induced apoptosis than mature DC. BA also induced mitochondrial membrane potential changes in DCs. These results demonstrate that BA induces selective apoptosis in immature DCs possibly through mitochondria-mediated pathway.

  12. Receptor tyrosine kinase-like orphan receptor 1, a target of NKX2-1/TTF-1 lineage-survival oncogene, inhibits apoptosis signal-regulating kinase 1-mediated pro-apoptotic signaling in lung adenocarcinoma.

    Science.gov (United States)

    Ida, Lisa; Yamaguchi, Tomoya; Yanagisawa, Kiyoshi; Kajino, Taisuke; Shimada, Yukako; Suzuki, Motoshi; Takahashi, Takashi

    2016-02-01

    We previously identified receptor tyrosine kinase-like orphan receptor 1 (ROR1) as a transcriptional target of the NKX2-1/TTF-1 lineage-survival oncogene in lung adenocarcinoma. ROR1 consequently sustains a favorable balance between pro-survival phosphatidylinositol 3-kinase-protein kinase B and pro-apoptotic apoptosis signal-regulating kinase 1 (ASK1)-p38MAPK signaling. In contrast to recent advances in understanding how ROR1 sustains pro-survival signaling, the mechanism of ROR1 repression of pro-apoptotic signaling remains rather elusive. In the present study, we investigated the underlying mechanism of ROR1-mediated inhibition of the ASK1-p38MAPK signaling pathway. Growth inhibition mediated by siROR1 was partially but significantly alleviated by ASK1 co-knockdown in lung adenocarcinoma cell lines. Also, ASK1 phosphorylation at Thr845, which reflects its activated state, was clearly inhibited by ROR1 overexpression in both steady state and oxidative stress-elicited conditions in MSTO-211H cells. In addition, we found that ROR1 was physically associated with ASK1 at the C-terminal serine threonine-rich domain of ROR1. Furthermore, ROR1 kinase activity was shown to be required to repress the ASK1-p38 axis and oxidative stress-induced cell death. The present findings thus support our notion that ROR1 sustains lung adenocarcinoma survival, at least in part, through direct physical interaction with ASK1 and consequential repression of the pro-apoptotic ASK1-p38 axis in a ROR1 kinase activity-dependent manner. PMID:26661061

  13. Calpain Activator Dibucaine Induces Platelet Apoptosis

    Directory of Open Access Journals (Sweden)

    Jun Liu

    2011-03-01

    Full Text Available Calcium-dependent calpains are a family of cysteine proteases that have been demonstrated to play key roles in both platelet glycoprotein Ibα shedding and platelet activation and altered calpain activity is associated with thrombotic thrombocytopenic purpura. Calpain activators induce apoptosis in several types of nucleated cells. However, it is not clear whether calpain activators induce platelet apoptosis. Here we show that the calpain activator dibucaine induced several platelet apoptotic events including depolarization of the mitochondrial inner transmembrane potential, up-regulation of Bax and Bak, down-regulation of Bcl-2 and Bcl-XL, caspase-3 activation and phosphatidylserine exposure. Platelet apoptosis elicited by dibucaine was not affected by the broad spectrum metalloproteinase inhibitor GM6001. Furthermore, dibucaine did not induce platelet activation as detected by P-selectin expression and PAC-1 binding. However, platelet aggregation induced by ristocetin or α-thrombin, platelet adhesion and spreading on von Willebrand factor were significantly inhibited in platelets treated with dibucaine. Taken together, these data indicate that dibucaine induces platelet apoptosis and platelet dysfunction.

  14. Techniques to Distinguish Apoptosis from Necroptosis.

    Science.gov (United States)

    Feoktistova, Maria; Wallberg, Fredrik; Tenev, Tencho; Geserick, Peter; Leverkus, Martin; Meier, Pascal

    2016-04-01

    The processes by which cells die are as tightly regulated as those that govern cell growth and proliferation. Recent studies of the molecular pathways that regulate and execute cell death have uncovered a plethora of signaling cascades that lead to distinct modes of cell death, including "apoptosis," "necrosis," "autophagic cell death," and "mitotic catastrophe." Cells can readily switch from one form of death to another; therefore, it is vital to have the ability to monitor the form of death that cells are undergoing. A number of techniques are available that allow the detection of cell death and when combined with either knockdown approaches or inhibitors of specific signaling pathways, such as caspase or RIP kinase pathways, they allow the rapid dissection of divergent cell death pathways. However, techniques that reveal the end point of cell death cannot reconstruct the sequence of events that have led to death; therefore, they need to be complemented with methods that can distinguish all forms of cell death. Apoptotic cells frequently undergo secondary necrosis under in vitro culture conditions; therefore, novel methods relying on high-throughput time-lapse fluorescence video microscopy are necessary to provide temporal resolution to cell death events. Further, visualizing the assembly of multiprotein signaling hubs that can execute a