WorldWideScience

Sample records for cell activation proliferation

  1. Capsaicin modulates proliferation, migration, and activation of hepatic stellate cells.

    Science.gov (United States)

    Bitencourt, Shanna; Mesquita, Fernanda; Basso, Bruno; Schmid, Júlia; Ferreira, Gabriela; Rizzo, Lucas; Bauer, Moises; Bartrons, Ramon; Ventura, Francesc; Rosa, Jose Luis; Mannaerts, Inge; van Grunsven, Leo Adrianus; Oliveira, Jarbas

    2014-03-01

    Capsaicin, the active component of chili pepper, has been reported to have antiproliferative and anti-inflammatory effects on a variety of cell lines. In the current study, we aimed to investigate the effects of capsaicin during HSC activation and maintenance. Activated and freshly isolated HSCs were treated with capsaicin. Proliferation was measured by incorporation of EdU. Cell cycle arrest and apoptosis were investigated using flow cytometry. The migratory response to chemotactic stimuli was evaluated by a modified Boyden chamber assay. Activation markers and inflammatory cytokines were determined by qPCR, immunocytochemistry, and flow cytometry. Our results show that capsaicin reduces HSC proliferation, migration, and expression of profibrogenic markers of activated and primary mouse HSCs. In conclusion, the present study shows that capsaicin modulates proliferation, migration, and activation of HSC in vitro. PMID:23955514

  2. Modulation of insulin degrading enzyme activity and liver cell proliferation

    OpenAIRE

    Pivovarova, Olga; von Loeffelholz, Christian; Ilkavets, Iryna; Sticht, Carsten; Zhuk, Sergei; Murahovschi, Veronica; Lukowski, Sonja; Döcke, Stephanie; Kriebel, Jennifer; de las Heras Gala, Tonia; Malashicheva, Anna; Kostareva, Anna; Lock, Johan F; Stockmann, Martin; Grallert, Harald

    2015-01-01

    Diabetes mellitus type 2 (T2DM), insulin therapy, and hyperinsulinemia are independent risk factors of liver cancer. Recently, the use of a novel inhibitor of insulin degrading enzyme (IDE) was proposed as a new therapeutic strategy in T2DM. However, IDE inhibition might stimulate liver cell proliferation via increased intracellular insulin concentration. The aim of this study was to characterize effects of inhibition of IDE activity in HepG2 hepatoma cells and to analyze liver specific expre...

  3. Peroxisome proliferator-activated receptor gamma overexpression suppresses proliferation of human colon cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Tsukahara, Tamotsu, E-mail: ttamotsu@shinshu-u.ac.jp [Department of Integrative Physiology and Bio-System Control, Shinshu University School of Medicine, 3-1-1 Asahi, Matsumoto, Nagano 390-8621 (Japan); Haniu, Hisao [Department of Orthopaedic Surgery, Shinshu University School of Medicine, 3-1-1 Asahi, Matsumoto, Nagano 390-8621 (Japan)

    2012-08-03

    Highlights: Black-Right-Pointing-Pointer We examined the correlation between PPAR{gamma} expression and cell proliferation. Black-Right-Pointing-Pointer PPAR{gamma} overexpression reduces cell viability. Black-Right-Pointing-Pointer We show the synergistic effect of cell growth inhibition by a PPAR{gamma} agonist. -- Abstract: Peroxisome proliferator-activated receptor gamma (PPAR{gamma}) plays an important role in the differentiation of intestinal cells and tissues. Our previous reports indicate that PPAR{gamma} is expressed at considerable levels in human colon cancer cells. This suggests that PPAR{gamma} expression may be an important factor for cell growth regulation in colon cancer. In this study, we investigated PPAR{gamma} expression in 4 human colon cancer cell lines, HT-29, LOVO, DLD-1, and Caco-2. Real-time polymerase chain reaction (PCR) and Western blot analysis revealed that the relative levels of PPAR{gamma} mRNA and protein in these cells were in the order HT-29 > LOVO > Caco-2 > DLD-1. We also found that PPAR{gamma} overexpression promoted cell growth inhibition in PPAR{gamma} lower-expressing cell lines (Caco-2 and DLD-1), but not in higher-expressing cells (HT-29 and LOVO). We observed a correlation between the level of PPAR{gamma} expression and the cells' sensitivity for proliferation.

  4. Genetic abolishment of hepatocyte proliferation activates hepatic stem cells.

    Directory of Open Access Journals (Sweden)

    Yoko Endo

    Full Text Available Quiescent hepatic stem cells (HSCs can be activated when hepatocyte proliferation is compromised. Chemical injury rodent models have been widely used to study the localization, biomarkers, and signaling pathways in HSCs, but these models usually exhibit severe promiscuous toxicity and fail to distinguish damaged and non-damaged cells. Our goal is to establish new animal models to overcome these limitations, thereby providing new insights into HSC biology and application. We generated mutant mice with constitutive or inducible deletion of Damaged DNA Binding protein 1 (DDB1, an E3 ubiquitin ligase, in hepatocytes. We characterized the molecular mechanism underlying the compensatory activation and the properties of oval cells (OCs by methods of mouse genetics, immuno-staining, cell transplantation and gene expression profiling. We show that deletion of DDB1 abolishes self-renewal capacity of mouse hepatocytes in vivo, leading to compensatory activation and proliferation of DDB1-expressing OCs. Partially restoring proliferation of DDB1-deficient hepatocytes by ablation of p21, a substrate of DDB1 E3 ligase, alleviates OC proliferation. Purified OCs express both hepatocyte and cholangiocyte markers, form colonies in vitro, and differentiate to hepatocytes after transplantation. Importantly, the DDB1 mutant mice exhibit very minor liver damage, compared to a chemical injury model. Microarray analysis reveals several previously unrecognized markers, including Reelin, enriched in oval cells. Here we report a genetic model in which irreversible inhibition of hepatocyte duplication results in HSC-driven liver regeneration. The DDB1 mutant mice can be broadly applied to studies of HSC differentiation, HSC niche and HSCs as origin of liver cancer.

  5. Human retinal pigment epithelial cells inhibit proliferation and IL2R expression of activated T cells

    DEFF Research Database (Denmark)

    Kaestel, Charlotte G; Jørgensen, Annette; Nielsen, Mette;

    2002-01-01

    The purpose of this study was to characterize the effects of human retinal pigment epithelial (RPE) cells on activated T cells. Activated T cells were cocultured with adult and foetal human RPE cells whereafter apoptosis and proliferation were determined by flow cytometry and (3)H......-Thymidine incorporation assay, respectively. T cells and RPE cells were cultured directly together or in a transwell system for determination of the effect of cell contact. The importance of cell surface molecules was examined by application of a panel of blocking antibodies (CD2, CD18, CD40, CD40L, CD54, CD58......) in addition to use of TCR negative T cell lines. The expression of IL2R-alpha -beta and -gamma chains of activated T cells was analysed by flow cytometry after incubation of T cells alone or with RPE cells. Human RPE cells were found to inhibit the proliferation of activated T cells by a cell contact...

  6. H pylori stimulates proliferation of gastric cancer cells through activating mitogen-activated protein kinase cascade

    Institute of Scientific and Technical Information of China (English)

    Yong-Chang Chen; Ying Wang; Jing-Yan Li; Wen-Rong Xu; You-Li Zhang

    2006-01-01

    AIM: To explore the mechanism by which H pylori causes activation of gastric epithelial cells.METHODS: A VacA (+) and CagA (+) standard Hpyloriline NCTC 11637 and a human gastric adenocarcinoma derived gastric epithelial cell line BGC-823 were applied in the study. MTT assay and 3H-TdR incorporation test were used to detect the proliferation of BGC-823 cells and Western blotting was used to detect the activity and existence of related proteins.RESULTS: Incubation with Hpylori extract increased the proliferation of gastric epithelial cells, reflected by both live cell number and DNA synthesis rate. The activity of extracellular signal-regulated protein kinase (ERK) signal transduction cascade increased within 20 min after incubation with Hpylori extract and appeared to be a sustained event. MAPK/ERK kinase (MEK) inhibitor PD98059abolished the action of H pylori extract on both ERK activity and cell proliferation. Incubation with H pyloriextract increased c-Fos expression and SRE-dependentgene expression. H pylori extract caused phosphorylation of several proteins including a protein with molecular size of 97.4 kDa and tyrosine kinase inhibitor genistein inhibited the activation of ERK and the proliferation of cells caused by H pylori extract.CONCLUSION: Biologically active elements in H pylori extract cause proliferation of gastric epithelial cells through activating tyrosine kinase and ERK signal transduction cascade.

  7. Human Liver Stem Cells Suppress T-Cell Proliferation, NK Activity, and Dendritic Cell Differentiation

    Directory of Open Access Journals (Sweden)

    Stefania Bruno

    2016-01-01

    Full Text Available Human liver stem cells (HLSCs are a mesenchymal stromal cell-like population resident in the adult liver. Preclinical studies indicate that HLSCs could be a good candidate for cell therapy. The aim of the present study was to evaluate the immunogenicity and the immunomodulatory properties of HLSCs on T-lymphocytes, natural killer cells (NKs, and dendritic cells (DCs in allogeneic experimental settings. We found that HLSCs inhibited T-cell proliferation by a mechanism independent of cell contact and dependent on the release of prostaglandin E2 (PGE2 and on indoleamine 2,3-dioxygenase activity. When compared with mesenchymal stromal cells (MSCs, HLSCs were more efficient in inhibiting T-cell proliferation. At variance with MSCs, HLSCs did not elicit NK degranulation. Moreover, HLSCs inhibited NK degranulation against K562, a NK-sensitive target, by a mechanism dependent on HLA-G release. When tested on DC generation from monocytes, HLSCs were found to impair DC differentiation and DCs ability to induce T-cell proliferation through PGE2. This study shows that HLSCs have immunomodulatory properties similar to MSCs, but, at variance with MSCs, they do not elicit a NK response.

  8. CCL5 activation of CCR5 regulates cell metabolism to enhance proliferation of breast cancer cells.

    Science.gov (United States)

    Gao, Darrin; Rahbar, Ramtin; Fish, Eleanor N

    2016-06-01

    In earlier studies, we showed that CCL5 enhances proliferation and survival of MCF-7 breast cancer cells in an mTOR-dependent manner and we provided evidence that, for T cells, CCL5 activation of CCR5 results in increased glycolysis and enhanced ATP production. Increases in metabolic activity of cancer cells, specifically increased glycolytic activity and increased expression of glucose transporters, are associated with tumour progression. In this report, we provide evidence that CCL5 enhances the proliferation of human breast cancer cell lines (MDA-MB-231, MCF-7) and mouse mammary tumour cells (MMTV-PyMT), mediated by CCR5 activation. Concomitant with enhanced proliferation we show that CCL5 increases cell surface expression of the glucose transporter GLUT1, and increases glucose uptake and ATP production by these cells. Blocking CCL5-inducible glucose uptake abrogates the enhanced proliferation induced by CCL5. We provide evidence that increased glucose uptake is associated with enhanced glycolysis, as measured by extracellular acidification. Moreover, CCL5 enhances the invasive capacity of these breast cancer cells. Using metabolomics, we demonstrate that the metabolic signature of CCL5-treated primary mouse mammary tumour cells reflects increased anabolic metabolism. The implications are that CCL5-CCR5 interactions in the tumour microenvironment regulate metabolic events, specifically glycolysis, to promote tumour proliferation and invasion.

  9. Cellular, Molecular Consequences of Peroxisome Proliferator- Activated Receptor-δ Activation in Ovarian Cancer Cells

    Directory of Open Access Journals (Sweden)

    Sara Vignati

    2006-10-01

    Full Text Available Peroxisome proliferator-activated receptor-δ (PPAR-δ is a ligand-activated transcription factor. In addition to its canonical role in lipid, glucose metabolism, PPAR-δ controls cell proliferation, death, differentiation in several tissues. Here we have examined the expression of PPAR-δ in ovarian tumors, the cellular, molecular consequences of its activation in ovarian cancer cells. PPAR-δ was expressed in a large number of epithelial ovarian tumors, cell lines. The PPAR-δ lig, ciglitazone inhibited the growth, clonogenic survival of ovarian cancer cells, inducing cell cycle arrest, cell death. Growth inhibition by ciglitazone was reversed by the PPAR-δ antagonist GW9662, indicating the involvement of PPAR-δ- dependent mechanisms. Microarray-based gene profiling revealed complex changes in the transcriptional program of ovarian cancer cells on treatment with ciglitazone, identified multiple pathways that may contribute to PPAR-δ ligands' antitumor activity. Genes upregulated by ciglitazone were predominantly associated with metabolic, differentiation, tumorsuppressor pathways, whereas downregulated genes were involved in cell proliferation, cell cycle, cell organization, steroid biosynthesis. Collectively, our data indicate that PPAR-δ activation by selective agonists is a valid strategy for ovarian cancer therapy, prevention, should be tested alone, in combination with other anticancer drugs.

  10. Differential Effects of Tacrolimus versus Sirolimus on the Proliferation, Activation and Differentiation of Human B Cells

    OpenAIRE

    Traitanon, Opas; Mathew, James M.; La Monica, Giovanna; Xu, Luting; Mas, Valeria; Gallon, Lorenzo

    2015-01-01

    The direct effect of immunosuppressive drugs calcineurin inhibitor (Tacrolimus, TAC) and mTOR inhibitor (Sirolimus, SRL) on B cell activation, differentiation and proliferation is not well documented. Purified human B cells from healthy volunteers were stimulated through the B Cell Receptor with Anti-IgM + anti-CD40 + IL21 in the absence / presence of TAC or SRL. A variety of parameters of B cell activity including activation, differentiation, cytokine productions and proliferation were monit...

  11. KIPase activity is a novel caspase-like activity associated with cell proliferation.

    Science.gov (United States)

    Medina-Palazon, Cahora; Bernard, Emmanuelle; Frost, Victoria; Morley, Simon; Sinclair, Alison J

    2004-07-01

    A novel caspase-like activity, which is directly regulated with cell proliferation is a candidate to regulate the abundance of the cyclin-dependent kinase inhibitor, p27(KIP1), in human lymphoid cells. This activity, which we term KIPase activity, can also cleave a subset of caspase substrates. Here we demonstrate that KIPase is a novel enzyme distinct from any of the previously characterized human caspases. We show that KIPase is active in a variety of cell lineages, its activity is associated with the proliferation of the human T-cell line, Jurkat, and is not inhibited by the broad spectrum caspase inhibitor z-VAD-fmk. Gel filtration analysis revealed that KIPase has a native molecular mass of approximately 100-200 kDa. Furthermore, the activity of KIPase does not change during apoptosis induced by either ligation of FAS or exposure of cells to etoposide. The uniqueness of KIPase is demonstrated by the fact that none of the human caspases tested (1-10) are able to cleave a specific KIPase substrate (Ac-DPSD-AMC) and that an aldehyde modified derivative of the DPSD tetra peptide is unable to inhibit caspases, but is a good inhibitor of KIPase activity. This supports a hypothesis whereby KIPase is a currently unidentified caspase-like enzyme which regulates the abundance of p27(KIP1) in a proliferation-dependent manner.

  12. Cell proliferation is a key determinant of the outcome of FOXO3a activation

    Energy Technology Data Exchange (ETDEWEB)

    Poulsen, Raewyn C., E-mail: raewyn.poulsen@gmail.com; Carr, Andrew J.; Hulley, Philippa A.

    2015-06-19

    The FOXO family of forkhead transcription factors have a pivotal role in determining cell fate in response to oxidative stress. FOXO activity can either promote cell survival or induce cell death. Increased FOXO-mediated cell death has been implicated in the pathogenesis of degenerative diseases affecting musculoskeletal tissues. The aim of this study was to determine the conditions under which one member of the FOXO family, FOXO3a, promotes cell survival as opposed to cell death. Treatment of primary human tenocytes with 1 pM hydrogen peroxide for 18 h resulted in increased protein levels of FOXO3a. In peroxide-treated cells cultured in low serum media, FOXO3a inhibited cell proliferation and protected against apoptosis. However in peroxide treated cells cultured in high serum media, cell proliferation was unchanged but level of apoptosis significantly increased. Similarly, in tenocytes transduced to over-express FOXO3a, cell proliferation was inhibited and level of apoptosis unchanged in cells cultured in low serum. However there was a robust increase in cell death in FOXO3a-expressing cells cultured in high serum. Inhibition of cell proliferation in either peroxide-treated or FOXO3a-expressing cells cultured in high serum protected against apoptosis induction. Conversely, addition of a Chk2 inhibitor to peroxide-treated or FOXO3a-expressing cells overrode the inhibitory effect of FOXO3a on cell proliferation and led to increased apoptosis in cells cultured in low serum. This study demonstrates that proliferating cells may be particularly susceptible to the apoptosis-inducing actions of FOXO3a. Inhibition of cell proliferation by FOXO3a may be a critical event in allowing the pro-survival rather than the pro-apoptotic activity of FOXO3a to prevail. - Highlights: • FOXO3a activity can result in either promotion of cell survival or apoptosis. • The outcome of FOXO3a activation differs in proliferating compared to non-proliferating cells. • Proliferating

  13. Human Liver Stem Cells Suppress T-Cell Proliferation, NK Activity, and Dendritic Cell Differentiation

    OpenAIRE

    Stefania Bruno; Cristina Grange; Marta Tapparo; Chiara Pasquino; Renato Romagnoli; Ennia Dametto; Antonio Amoroso; Ciro Tetta; Giovanni Camussi

    2016-01-01

    Human liver stem cells (HLSCs) are a mesenchymal stromal cell-like population resident in the adult liver. Preclinical studies indicate that HLSCs could be a good candidate for cell therapy. The aim of the present study was to evaluate the immunogenicity and the immunomodulatory properties of HLSCs on T-lymphocytes, natural killer cells (NKs), and dendritic cells (DCs) in allogeneic experimental settings. We found that HLSCs inhibited T-cell proliferation by a mechanism independent of cell co...

  14. Cell culture density affects the proliferation activity of human adipose tissue stem cells.

    Science.gov (United States)

    Kim, Dae Seong; Lee, Myoung Woo; Ko, Young Jong; Chun, Yong Hoon; Kim, Hyung Joon; Sung, Ki Woong; Koo, Hong Hoe; Yoo, Keon Hee

    2016-01-01

    In this study, we investigated the effect of cell density on the proliferation activity of human mesenchymal stem cells (MSCs) derived from adipose tissue (AT-MSCs) over time in culture. Passage #4 (P4) and #12 (P12) AT-MSCs from two donors were plated at a density of 200 (culture condition 1, CC1) or 5000 (culture condition 2, CC2) cells cm(-2) . After 7 days of incubation, P4 and P12 AT-MSCs cultured in CC1 were thin and spindle-shaped, whereas those cultured in CC2 had extensive cell-to-cell contacts and an expanded cell volume. In addition, P4 and P12 AT-MSCs in CC1 divided more than three times, while those in CC2 divided less than once on average. Flow cytometric analysis using 5(6)-carboxyfluorescein diacetate N-succinimidyl ester dye showed that the fluorescence intensity of AT-MSCs was lower in CC1 than in CC2. Furthermore, expression of proliferation-associated genes, such as CDC45L, CDC20A and KIF20A, in P4 AT-MSCs was higher in CC1 than in CC2, and this difference was also observed in P12 AT-MSCs. These data demonstrated that cell culture density affects the proliferation activity of MSCs, suggesting that it is feasible to design a strategy to prepare suitable MSCs using specific culture conditions.

  15. Peroxisome proliferator-activated receptor γ ligands regulate neural stem cell proliferation and differentiation in vitro and in vivo

    OpenAIRE

    Morales-García, José A.; Luna Medina, Rosario de; Alfaro-Cervello, Clara; Cortés-Canteli, Marta; Santos, Ángel; García-Verdugo, J. M.; Pérez Castillo, Ana

    2011-01-01

    Peroxisome proliferator-activated receptor gamma (PPARγ) belongs to a family of ligand-activated nuclear receptors and its ligands are known to control many physiological and pathological situations. Its role in the central nervous system has been under intense analysis during the last years. Here we show a novel function for PPARγ in controlling stem cell expansion in the adult mammalian brain. Adult rats treated with pioglitazone, a specific ligand of PPARγ, had elevated numbers of prolifer...

  16. SIRT2 activates G6PD to enhance NADPH production and promote leukaemia cell proliferation

    Science.gov (United States)

    Xu, Shuang-Nian; Wang, Tian-Shi; Li, Xi; Wang, Yi-Ping

    2016-01-01

    Like most other types of cancer cells, leukaemia cells undergo metabolic reprogramming to support rapid proliferation through enhancing biosynthetic processes. Pentose phosphate pathway (PPP) plays a pivotal role in meeting the anabolic demands for cancer cells. However, the molecular mechanism by which PPP contributes to leukaemia remains elusive. Here, we report that leukaemia cell proliferation is dependent on the oxidative branch of PPP, in particular the first and rate-limiting enzyme glucose-6-phosphate dehydrogenase (G6PD). Knockdown of G6PD reduces NADPH level in acute myeloid leukaemia (AML) cell lines. Exogenous lipid supplements partially restore the proliferation of G6PD-depleted cells. Deacetylase SIRT2 promotes NADPH production through deacetylating G6PD at lysine 403 (K403). Activation of G6PD by SIRT2 supports the proliferation and clonogenic activity of leukaemia cells. Chemical inhibitors against SIRT2 suppress G6PD activity, leading to reduced cell proliferation of leukaemia cells, but not normal hematopoietic stem and progenitor cells. Importantly, SIRT2 is overexpressed in clinical AML samples, while K403 acetylation is downregulated and G6PD catalytic activity is increased comparing to that of normal control. Together, our study reveals that acetylation regulation of G6PD is involved in the metabolic reprogramming of AML, and SIRT2 serves as a promising target for further therapeutic investigations. PMID:27586085

  17. SIRT2 activates G6PD to enhance NADPH production and promote leukaemia cell proliferation.

    Science.gov (United States)

    Xu, Shuang-Nian; Wang, Tian-Shi; Li, Xi; Wang, Yi-Ping

    2016-01-01

    Like most other types of cancer cells, leukaemia cells undergo metabolic reprogramming to support rapid proliferation through enhancing biosynthetic processes. Pentose phosphate pathway (PPP) plays a pivotal role in meeting the anabolic demands for cancer cells. However, the molecular mechanism by which PPP contributes to leukaemia remains elusive. Here, we report that leukaemia cell proliferation is dependent on the oxidative branch of PPP, in particular the first and rate-limiting enzyme glucose-6-phosphate dehydrogenase (G6PD). Knockdown of G6PD reduces NADPH level in acute myeloid leukaemia (AML) cell lines. Exogenous lipid supplements partially restore the proliferation of G6PD-depleted cells. Deacetylase SIRT2 promotes NADPH production through deacetylating G6PD at lysine 403 (K403). Activation of G6PD by SIRT2 supports the proliferation and clonogenic activity of leukaemia cells. Chemical inhibitors against SIRT2 suppress G6PD activity, leading to reduced cell proliferation of leukaemia cells, but not normal hematopoietic stem and progenitor cells. Importantly, SIRT2 is overexpressed in clinical AML samples, while K403 acetylation is downregulated and G6PD catalytic activity is increased comparing to that of normal control. Together, our study reveals that acetylation regulation of G6PD is involved in the metabolic reprogramming of AML, and SIRT2 serves as a promising target for further therapeutic investigations. PMID:27586085

  18. Surfactant protein A integrates activation signal strength to differentially modulate T cell proliferation.

    Science.gov (United States)

    Mukherjee, Sambuddho; Giamberardino, Charles; Thomas, Joseph; Evans, Kathy; Goto, Hisatsugu; Ledford, Julie G; Hsia, Bethany; Pastva, Amy M; Wright, Jo Rae

    2012-02-01

    Pulmonary surfactant lipoproteins lower the surface tension at the alveolar-airway interface of the lung and participate in host defense. Previous studies reported that surfactant protein A (SP-A) inhibits lymphocyte proliferation. We hypothesized that SP-A-mediated modulation of T cell activation depends upon the strength, duration, and type of lymphocyte activating signals. Modulation of T cell signal strength imparted by different activating agents ex vivo and in vivo in different mouse models and in vitro with human T cells shows a strong correlation between strength of signal (SoS) and functional effects of SP-A interactions. T cell proliferation is enhanced in the presence of SP-A at low SoS imparted by exogenous mitogens, specific Abs, APCs, or in homeostatic proliferation. Proliferation is inhibited at higher SoS imparted by different doses of the same T cell mitogens or indirect stimuli such as LPS. Importantly, reconstitution with exogenous SP-A into the lungs of SP-A(-/-) mice stimulated with a strong signal also resulted in suppression of T cell proliferation while elevating baseline proliferation in unstimulated T cells. These signal strength and SP-A-dependent effects are mediated by changes in intracellular Ca(2+) levels over time, involving extrinsic Ca(2+)-activated channels late during activation. These effects are intrinsic to the global T cell population and are manifested in vivo in naive as well as memory phenotype T cells. Thus, SP-A appears to integrate signal thresholds to control T cell proliferation. PMID:22219327

  19. Langerhans cells in Langerhans cell granulomatosis are not actively proliferating cells.

    OpenAIRE

    Brabencova, E.; Tazi, A.; Lorenzato, M; Bonay, M; Kambouchner, M.; Emile, J. F.; Hance, A J; Soler, P

    1998-01-01

    Pulmonary Langerhans cell granulomatosis (LCG), also called histiocytosis X, is a disorder of unknown etiology characterized by the presence of destructive granulomas containing numerous Langerhans cells (LCs). The process may be localized or multifocal, and it remains unclear whether the same pathogenic mechanism is involved in all forms of the disease. It is often assumed that the massive accumulation of LCs at the sites of the lesions results from the abnormal proliferation of these cells,...

  20. Serum Amyloid A Induces Inflammation, Proliferation and Cell Death in Activated Hepatic Stellate Cells.

    Science.gov (United States)

    Siegmund, Sören V; Schlosser, Monika; Schildberg, Frank A; Seki, Ekihiro; De Minicis, Samuele; Uchinami, Hiroshi; Kuntzen, Christian; Knolle, Percy A; Strassburg, Christian P; Schwabe, Robert F

    2016-01-01

    Serum amyloid A (SAA) is an evolutionary highly conserved acute phase protein that is predominantly secreted by hepatocytes. However, its role in liver injury and fibrogenesis has not been elucidated so far. In this study, we determined the effects of SAA on hepatic stellate cells (HSCs), the main fibrogenic cell type of the liver. Serum amyloid A potently activated IκB kinase, c-Jun N-terminal kinase (JNK), Erk and Akt and enhanced NF-κB-dependent luciferase activity in primary human and rat HSCs. Serum amyloid A induced the transcription of MCP-1, RANTES and MMP9 in an NF-κB- and JNK-dependent manner. Blockade of NF-κB revealed cytotoxic effects of SAA in primary HSCs with signs of apoptosis such as caspase 3 and PARP cleavage and Annexin V staining. Serum amyloid A induced HSC proliferation, which depended on JNK, Erk and Akt activity. In primary hepatocytes, SAA also activated MAP kinases, but did not induce relevant cell death after NF-κB inhibition. In two models of hepatic fibrogenesis, CCl4 treatment and bile duct ligation, hepatic mRNA levels of SAA1 and SAA3 were strongly increased. In conclusion, SAA may modulate fibrogenic responses in the liver in a positive and negative fashion by inducing inflammation, proliferation and cell death in HSCs. PMID:26937641

  1. Malignant T cells exhibit CD45 resistant Stat3 activation and proliferation in cutaneous

    DEFF Research Database (Denmark)

    Krejsgaard, Thorbjørn Frej; Helvad, Rikke; Ralfkiaer, Elisabeth;

    2010-01-01

    CD45 is a protein tyrosine phosphatase, which is well-known for regulating antigen receptor signalling in T and B cells via its effect on Src kinases. It has recently been shown that CD45 can also dephosphorylate Janus kinases (Jaks) and thereby regulate Signal transducer and activator of transcr......-mediated inhibition of proliferation. In conclusion, our data suggest that CD45 dysregulation might play a role in the aberrant proliferation and Jak3/Stat3 activation in CTCL....

  2. Propofol induces proliferation and invasion of gallbladder cancer cells through activation of Nrf2

    Directory of Open Access Journals (Sweden)

    Zhang Lingmin

    2012-08-01

    Full Text Available Abstract Background Propofol is one of the most commonly used intravenous anaesthetic agents during cancer resection surgery, but the effect of propofol on gallbladder cancer is not clear. NF-E2-related factor 2 (Nrf2 is abundantly expressed in cancer cells and relates to proliferation, invasion, and chemoresistance. The aims of the current study were to evaluate effects of propofol on the behavior of human GC cells and role of Nrf2 in these effects. Method The effects of propofol on cell proliferation, apoptosis, and invasion were detected by MTT assays, flow cytometry, and transwell assay. Also, activation of Nrf2 was determined by western blot, RT-PCR, and immunofluorescence assays. Nrf2 was knocked-down in GBC-SD cells by shRNA before evaluating the role of Nrf2 in the influence of propofol on biological behaviors. Results Propofol promoted the proliferation of GBC-SD cells in a dose- and time- dependent manner. After exposure to propofol for 48 h, GBC-SD cells showed decreased apoptosis and increased invasion. Also, propofol over-expressed Nrf2 at both the protein and mRNA levels and induced translocation of Nrf2 into the nucleus. Finally, loss of Nrf2 by shRNA reversed the effect of propofol on cell proliferation, apoptosis, and invasion. Conclusion Propofol induces proliferation and promotes invasion of GC cells through activation of Nrf2.

  3. Mast Cell-activated Bone Marrow Mesenchymal Stromal Cells Regulate Proliferation and Lineage Commitment of CD34+ Progenitor cells

    Directory of Open Access Journals (Sweden)

    Zoulfia eAllakhverdi

    2013-12-01

    Full Text Available Background: Shortly after allergen exposure, the number of bone marrow and circulating CD34+ progenitors increases. We aim to analyze the possible mechanism whereby the allergic reaction stimulates bone marrow to release these effector cells in increased numbers. We hypothesize that mast cells may play a predominant role in this process. Objective: To examine the effect of IgE-activated mast cells on bone marrow mesenchymal stromal cells which regulate proliferation and differentiation of CD34+ progenitors. Methods: Primary mast cells were derived from CD34+ precursors and activated with IgE/anti-IgE. Bone marrow mesenchymal stromal cells were co-cultured with CD34+ progenitor cells and stimulated with IL1/TNF or IgE/anti-IgE activated mast cells in Transwell system. Results: Bone marrow mesenchymal stromal cells produce low level of TSLP under steady state conditions, which is markedly increased by stimulation with proinflammatory cytokines IL-1 and TNF or IgE-activated mast cells. The latter also triggers BM-MSCs production of G-CSF, and GM-CSF while inhibiting SDF-1. Mast cell-activated mesenchymal stromal cells stimulate CD34+ cells to proliferate and to regulate their expression of early allergy-associated genes. Conclusion and Clinical Relevance: This in vitro study indicates that IgE-activated mast cells trigger bone marrow mesenchymal stromal cells to release TSLP and hematopoietic growth factors and to regulate the proliferation and lineage commitment of CD34+ precursor cells. The data predict that the effective inhibition of mast cells should impair mobilization and accumulation of allergic effector cells and thereby reduce the severity of allergic diseases.

  4. Surfactant Protein A integrates activation signal strength to differentially modulate T cell proliferation

    OpenAIRE

    Mukherjee, Sambuddho; Giamberardino, Charles; Thomas, Joseph; Evans, Kathy; GOTO, HISATSUGU; Ledford, Julie G.; Hsia, Bethany; Pastva, Amy M.; Wright, Jo Rae

    2012-01-01

    Pulmonary surfactant lipoproteins lower the surface tension at the alveolar:airway interface of the lung and participate in host defense. Previous studies reported that surfactant protein A (SP-A) inhibits lymphocyte proliferation. We hypothesized that SP-A mediated modulation of T cell activation depends upon the strength, duration and type of lymphocyte activating signals. Modulation of T cell signal strength imparted by different activating agents ex and in vivo in different mouse models, ...

  5. Differential Effects of Tacrolimus versus Sirolimus on the Proliferation, Activation and Differentiation of Human B Cells.

    Directory of Open Access Journals (Sweden)

    Opas Traitanon

    Full Text Available The direct effect of immunosuppressive drugs calcineurin inhibitor (Tacrolimus, TAC and mTOR inhibitor (Sirolimus, SRL on B cell activation, differentiation and proliferation is not well documented. Purified human B cells from healthy volunteers were stimulated through the B Cell Receptor with Anti-IgM + anti-CD40 + IL21 in the absence / presence of TAC or SRL. A variety of parameters of B cell activity including activation, differentiation, cytokine productions and proliferation were monitored by flow cytometry. SRL at clinically relevant concentrations (6 ng/ml profoundly inhibited CD19(+ B cell proliferation compared to controls whereas TAC at similar concentrations had a minimal effect. CD27(+ memory B cells were affected more by SRL than naïve CD27- B cells. SRL effectively blocked B cell differentiation into plasma cells (CD19(+CD138(+ and Blimp1(+/Pax5(low cells even at low dose (2 ng/ml, and totally eliminated them at 6 ng/ml. SRL decreased absolute B cell counts, but the residual responding cells acquired an activated phenotype (CD25(+/CD69(+ and increased the expression of HLA-DR. SRL-treated stimulated B cells on a per cell basis were able to enhance the proliferation of allogeneic CD4(+CD25(- T cells and induce a shift toward the Th1 phenotype. Thus, SRL and TAC have different effects on B lymphocytes. These data may provide insights into the clinical use of these two agents in recipients of solid organ transplants.

  6. The X protein of hepatitis B virus activates hepatoma cell proliferation through repressing melanoma inhibitory activity 2 gene

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Yilin; Yang, Yang; Cai, Yanyan; Liu, Fang; Liu, Yingle; Zhu, Ying [State Key Laboratory of Virology, College of Life Sciences, and Chinese-French Liver Disease Research Institute at Zhongnan Hospital, Wuhan University, Wuhan 430072 (China); Wu, Jianguo, E-mail: jwu@whu.edu.cn [State Key Laboratory of Virology, College of Life Sciences, and Chinese-French Liver Disease Research Institute at Zhongnan Hospital, Wuhan University, Wuhan 430072 (China)

    2011-12-16

    Highlights: Black-Right-Pointing-Pointer We demonstrated that HBV represses MIA2 gene expression both invitro and in vivo. Black-Right-Pointing-Pointer The X protein of HBV plays a major role in such regulation. Black-Right-Pointing-Pointer Knock-down of MIA2 in HepG2 cells activates cell growth and proliferation. Black-Right-Pointing-Pointer HBx activates cell proliferation, over-expression of MIA2 impaired such regulation. Black-Right-Pointing-Pointer HBx activates hepatoma cell proliferation through repressing MIA2 expression. -- Abstract: Hepatocellular carcinoma (HCC) is the fourth leading cause of cancer deaths globally. Chronic hepatitis B virus (HBV) infection accounts for over 75% of all HCC cases; however, the molecular pathogenesis of HCC is not well understood. In this study, we found that the expression of the newly identified gene melanoma inhibitory activity 2 (MIA2) was reduced by HBV infection invitro and invivo, and that HBV X protein (HBx) plays a major role in this regulation. Recent studies have revealed that MIA2 is a potential tumor suppressor, and that, in most HCCs, MIA2 expression is down-regulated or lost. We found that the knock-down of MIA2 in HepG2 cells activated cell growth and proliferation, suggesting that MIA2 inhibits HCC cell growth and proliferation. In addition, the over-expression of HBx alone induced cell proliferation, whereas MIA2 over-expression impaired the HBx-mediated induction of proliferation. Taken together, our results suggest that HBx activates hepatoma cell growth and proliferation through repression of the potential tumor suppressor MIA2.

  7. Activation of peroxisome proliferator-activated receptor-β/δ (PPARβ/δ) inhibits human breast cancer cell line tumorigenicity

    OpenAIRE

    Yao, Pei-Li; Morales, Jose L.; Zhu, Bokai; Kang, Boo-Hyon; Gonzalez, Frank J; Peters, Jeffrey M.

    2014-01-01

    The effect of activation and over-expression of the nuclear receptor PPARβ/δ in human MDA-MB-231 (ER−) and MCF7 (ER+) breast cancer cell lines was examined. Target gene induction by ligand activation of PPARβ/δ was increased by over-expression of PPARβ/δ compared to controls. Over-expression of PPARβ/δ caused a decrease in cell proliferation in MCF7 and MDA-MB-231 cells compared to controls while ligand activation of PPARβ/δ further inhibited proliferation of MCF7 but not MDA-MB-231 cells. Ov...

  8. Keyhole limpet hemocyanin augmented the killing activity, cytokine production and proliferation of NK cells, and inhibited the proliferation of Meth A sarcoma cells in vitro

    Directory of Open Access Journals (Sweden)

    Md. Moklesur Rahman Sarker

    2014-01-01

    Full Text Available Objective: Keyhole limpet hemocyanin (KLH is a popular tumor vaccine carrier protein and an immunostimulant. The present study aimed to investigate the immunoregulatory activity of KLH on cytotoxicity, cytokines production, and proliferation of natural killer (NK cells. Moreover, antiproliferative activity of KLH on Meth A sarcoma cells was studied. Materials and Methods: Cytotoxicity was determined with killing ability of NK cells against yeast artificial chromosome (YAC-1 cells. Interferon-gamma (IFN-γ and tumor necrosis factor-alpha (TNF-α productions by NK cells were measured by enzyme-linked immunosorbent assay (ELISA. Proliferations of NK and Meth A cells were determined by [ 3 H]thymidine incorporated proliferation and 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide (MTT methods, respectively. Results: KLH at 6.25, 12.5, and 25 μg/well augmented cytotoxicity of NK cells against YAC-1 cells by 2.5, three, and five-times, respectively. KLH at 25 μg/well enhanced IFN-γ and TNF-α productions by 17- and 23-folds, respectively. The proliferation of NK cells was three times stimulated by KLH. The proliferation of Meth A cells was markedly inhibited by all the doses; the highest (4-folds higher inhibition was observed at a dose of KLH (25 μg/well. Conclusion: The study demonstrated the anticancer activity of KLH acting through the induction of NK cells and inhibition of cancer cells. KLH, therefore, may be a good candidate for an anticancer agent alone or in combination with other chemotherapeutic agents.

  9. Sleep restriction by forced activity reduces hippocampal cell proliferation

    NARCIS (Netherlands)

    Roman, Viktor; Van der Borght, K; Leemburg, SA; Van der Zee, EA; Meerlo, P

    2005-01-01

    Mounting evidence suggests that sleep loss negatively affects learning and memory processes through disruption of hippocampal function. In the present study, we examined whether sleep loss alters the generation, differentiation, and survival of new cells in the dentate gyrus. Rats were sleep restric

  10. Influence of acid and bile acid on ERK activity, PPARY expression and cell proliferation in normal human esophageal epithelial cells

    Institute of Scientific and Technical Information of China (English)

    Zhi-Ru Jiang; Jun Gong; Zhen-Ni Zhang; Zhe Qiao

    2006-01-01

    AIM: To observe the effects of acid and bile acid exposure on cell proliferation and the expression of extracellular signal-regulated protein kinase (ERK) and peroxisome proliferator-activated receptor Y (PPARy) in normal human esophageal epithelial cells in vitro.METHODS: In vitro cultured normal human esophageal epithelial cells were exposed to acidic media (pH 4.0-6.5), media containing different bile acid (250 μmol/L), media containing acid and bile acid, respectively.Cell proliferation was assessed using MTT and flow cytometry. The expressions of phosphorylated ERK1/2 and PPARy protein were determined by the immunoblotting technique.RESULTS: Acid-exposed (3 min) esophageal cells exhibited a significant increase in proliferation ratio,S phase of the cell cycle (P<0.05) and the level of phosphorylated ERK1/2 protein. When the acid-exposure period exceeded 6 min, we observed a decrease in proliferation ratio and S phase of the cell cycle, with an increased apoptosis ratio (P<0.05). Bile acid exposure (3-12 min) also produced an increase in proliferation ratio, S phase of the cell cycle (P<0.05)and phosphorylated ERK1/2 expression. On the contrary,deoxycholic acid (DCA) exposure (>20 min) decreased proliferation ratio. Compared with bile acid exposure (pH 7.4), bile acid exposure (pH 6.5, 4) significantly decreased proliferation ratio (P<0.05). There was no expression of PPARY in normal human esophageal epithelial cells.CONCLUSION: The rapid stimuli of acid or bile acid increase proliferation in normal human esophageal epithelial cells by activating the ERK pathway.

  11. Romidepsin reduces histone deacetylase activity, induces acetylation of histones, inhibits proliferation, and activates apoptosis in immortalized epithelial endometriotic cells.

    Science.gov (United States)

    Imesch, Patrick; Fink, Daniel; Fedier, André

    2010-12-01

    Romidepsin inhibited HDAC activity, produced acetylation of the histone proteins, up-regulated p21, and down-regulated cyclins B1 and D1, resulting in proliferation inhibition and apoptosis activation in 11z immortalized epithelial endometriotic cells. Our findings provide evidence that endometriotic cells are sensitive to the epigenetic effects of romidepsin and suggest that endometriosis may be therapeutically targeted by romidepsin.

  12. p55PIK Transcriptionally Activated by MZF1 Promotes Colorectal Cancer Cell Proliferation

    Directory of Open Access Journals (Sweden)

    Yu Deng

    2013-01-01

    Full Text Available p55PIK, regulatory subunit of class IA phosphatidylinositol 3-kinase (PI3K, plays a crucial role in cell cycle progression by interaction with tumor repressor retinoblastoma (Rb protein. A recent study showed that Rb protein can localize to the mitochondria in proliferative cells. Aberrant p55PIK expression may contribute to mitochondrial dysfunction in cancer progression. To reveal the mechanisms of p55PIK transcriptional regulation, the p55PIK promoter characteristics were analyzed. The data show that myeloid zinc finger 1, MZF1, is necessary for p55PIK gene transcription activation. ChIP (Chromatin immuno-precipitation assay shows that MZF1 binds to the cis-element “TGGGGA” in p55PIK promoter. In MZF1 overexpressed cells, the promoter activity, expression of p55PIK, and cell proliferation rate were observed to be significantly enhanced. Whereas in MZF1-silenced cells, the promoter activity and expression of p55PIK and cell proliferation level was statistically decreased. In CRC tissues, MZF1 and p55PIK mRNA expression were increased (P=0.046, P=0.047, resp.. A strong positive correlation (Rs=0.94 between MZF1 and p55PIK mRNA expression was observed. Taken together, we concluded that p55PIK is transcriptionally activated by MZF1, resulting in increased proliferation of colorectal cancer cells.

  13. Cellular and Molecular Consequences of Peroxisome Proliferator-Activated Receptor-γ Activation in Ovarian Cancer Cells1*

    OpenAIRE

    Vignati, Sara; Albertini, Veronica; Rinaldi, Andrea; Kwee, Ivo; RIVA Cristina; Oldrini, Rita; Capella, Carlo; Bertoni, Francesco; Carbone, Giuseppina M; Catapano, Carlo V.

    2006-01-01

    Peroxisome proliferator-activated receptor-γ (PPAR-γ) is a ligand-activated transcription factor. In addition to its canonical role in lipid and glucose metabolism, PPAR-γ controls cell proliferation, death, and differentiation in several tissues. Here we have examined the expression of PPAR-γ in ovarian tumors and the cellular and molecular consequences of its activation in ovarian cancer cells. PPAR-γ was expressed in a large number of epithelial ovarian tumors and cell lines. The PPAR-γ li...

  14. A role for Peroxisome Proliferator-Activated Receptor Beta in T cell development

    Science.gov (United States)

    Mothe-Satney, Isabelle; Murdaca, Joseph; Sibille, Brigitte; Rousseau, Anne-Sophie; Squillace, Raphaëlle; Le Menn, Gwenaëlle; Rekima, Akila; Larbret, Frederic; Pelé, Juline; Verhasselt, Valérie; Grimaldi, Paul A.; Neels, Jaap G.

    2016-01-01

    Metabolism plays an important role in T cell biology and changes in metabolism drive T cell differentiation and fate. Most research on the role of metabolism in T lymphocytes focuses on mature T cells while only few studies have investigated the role of metabolism in T cell development. In this study, we report that activation or overexpression of the transcription factor Peroxisome Proliferator-Activated Receptor β (PPARβ) increases fatty acid oxidation in T cells. Furthermore, using both in vivo and in vitro models, we demonstrate that PPARβ activation/overexpression inhibits thymic T cell development by decreasing proliferation of CD4−CD8− double-negative stage 4 (DN4) thymocytes. These results support a model where PPARβ activation/overexpression favours fatty acid- instead of glucose-oxidation in developing T cells, thereby hampering the proliferative burst normally occurring at the DN4 stage of T cell development. As a consequence, the αβ T cells that are derived from DN4 thymocytes are dramatically decreased in peripheral lymphoid tissues, while the γδ T cell population remains untouched. This is the first report of a direct role for a member of the PPAR family of nuclear receptors in the development of T cells. PMID:27680392

  15. Troglitazone inhibits endothelial cell proliferation through suppression of casein kinase 2 activity

    International Nuclear Information System (INIS)

    Troglitazone, an agonist of peroxisome proliferator activated receptorγ (PPARγ), has been reported to inhibit endothelial cell proliferation by suppressing Akt activation. Recently, it has been also proposed that phosphatase and tensin homolog deleted from chromosome 10 (PTEN) plays an important role in such effect of troglitazone. However, the mechanism of how troglitazone regulates PTEN remains to be elucidated. We therefore investigated the effects of troglitazone on casein kinase 2 (CK2), which is known to negatively regulate PTEN activity. Troglitazone significantly inhibited serum-induced proliferation of HUVEC in a concentration dependent manner. Serum-induced Akt and its downstream signaling pathway activation was attenuated by troglitazone (10 μM) pretreatment. The phosphorylation of PTEN, which was directly related to Akt activation, was decreased with troglitazone pretreatment and was inversely proportional to CK2 activity. DRB, a CK2 inhibitor, also showed effects similar to that of troglitazone on Akt and its downstream signaling molecules. In conclusion, our results suggest that troglitazone inhibits proliferation of HUVECs through suppression of CK2 activity rendering PTEN to remain activated, and this effect of troglitazone in HUVECs seems to be PPARγ independent

  16. Rosiglitazone enhances fluorouracil-induced apoptosis of HT-29 cells by activating peroxisome proliferator-activated receptor γ

    Institute of Scientific and Technical Information of China (English)

    Yan-Qin Zhang; Xiao-Qing Tang; Li Sun; Lin Dong; Yong Qin; Hua-Qing Liu; Hong Xia; Jian-Guo Cao

    2007-01-01

    AIM: To examine whether and how rosiglitazone enhances apoptosis induced by fluorouracil in human colon cancer (HT-29) cells.METHODS: Human colon cancer HT-29 cells were cultured in vitro and treated with fluorouracil and/or rosiglitazone. Proliferation and growth of HT-29 cells were evaluated by MTT assay and trypan blue exclusion methods, respectively. The apoptosis of HT-29 cells was determined by acridine orange/ethidium bromide staining and flow cytometry using PI fluorescence staining. The expressions of peroxisome proliferator-activated receptor y (PPARy), Bcl-2 and Bax in HT-29 cells were analyzed by Western blot.RESULTS: Although rosiglitazone at the concentration below 30 umol/L for 72 h exerted almost no inhibitory effect on proliferation and growth of HT-29 cells, it could significantly enhance fluorouracil-induced HT-29 cell proliferation and growth inhibition. Furthermore, 10 umol/L rosilitazone did not induce apoptosis of HT-29 cells but dramatically enhanced fluorouracil-induced apoptosis of HT-29 cells. However, rosiglitazone did not improve apoptosis induced by fluorouracil in HT-29 cells pretreated with GW9662, a PPARy antagonist. Meanwhile, the expression of Bax and PPARy was up-regulated, while the expression of Bcl-2 was down regulated in HT-29 cells treated with rosiglitazone in a time-dependent manner. However, the effect of rosiglitazone on Bcl-2 and Bax was blocked or diminished in the presence of GW9662.CONCLUSION: Rosiglitazone enhances fluorouracil-induced apoptosis of HT-29 cells by activating PPARγ.

  17. Effects of protein kinase C activators and staurosporine on protein kinase activity, cell survival, and proliferation in Tetrahymena thermophila

    DEFF Research Database (Denmark)

    Straarup, EM; Schousboe, P; Hansen, HQ;

    1997-01-01

    with either PMA or OAG, or at 2,500 cells ml-1. At 500 cells ml-1 PMA induced the in vivo phosphorylation of at least six proteins. The myelin basic protein fragment 4-14 was phosphorylated in vitro in crude extracts of a culture of 250,000 cells ml-1. Both the in vivo and the in vitro phosphorylation were......Autocrine factors prevent cell death in the ciliate Tetrahymena thermophila, a unicellular eukaryote, in a chemically defined medium. At certain growth conditions these factors are released at a sufficient concentration by > 500 cells ml-1 to support cell survival and proliferation. The protein...... kinase C activators phorbol 12-myristate 13-acetate (PMA) or 1-oleyl 2-acetate glycerol (OAG) when added to 250 cells ml-1 supported cell survival and proliferation. In the presence of the serine and threonine kinase inhibitor staurosporine the cells died both at 250 cells ml-1 in cultures supplemented...

  18. Farnesoid X receptor activation promotes cell proliferation via PDK4-controlled metabolic reprogramming

    Science.gov (United States)

    Xie, Yang; Wang, Hong; Cheng, Xuefang; Wu, Yuzheng; Cao, Lijuan; Wu, Mengqiu; Xie, Wen; Wang, Guangji; Hao, Haiping

    2016-01-01

    Farnesoid X receptor (FXR) plays a pivotal role in the regulation of various metabolic pathways as well as liver regeneration. However, the casual link between cell proliferative effects during liver regeneration and metabolic regulation of FXR was elusive. In this study, we found that FXR activation significantly promotes HepG2 cell proliferation accompanied with metabolic switch towards the excessive accumulation of aerobic glycolytic intermediates including lactic acid, pyruvate and the subsequently increased biosynthesis of glycine. This FXR-induced metabolic switch was found dependent on an up-regulation of pyruvate dehydrogenate kinase 4 (PDK4), a FXR target gene. FXR agonists were found to promote liver regeneration in the murine model of APAP induced liver injury, which was associated with a metabolic switch favoring the accumulation of glycolytic intermediates as precursors for generation of biomass. However, FXR activation has little effect on the glycolytic metabolism in healthy primary hepatocytes in vitro and the liver of healthy mice in vivo. Therefore, we conclude that FXR may promote the proliferation of tumor cells and the hepatocytes in the process of liver regeneration by activating the PDK4-mediated metabolic reprogramming to generate glycolytic intermediates essential for rapid biomass generation, establishing a mechanistic link between cell proliferation and metabolic switch. PMID:26728993

  19. Inhibition of water activated by far infrared functional ceramics on proliferation of hepatoma cells.

    Science.gov (United States)

    Zhang, Dongmei; Liang, Jinsheng; Ding, Yan; Meng, Junping; Zhang, Guangchuan

    2014-05-01

    Rare earth (RE)/tourmaline composite materials prepared by the precipitation method are added to the ceramic raw materials at a certain percentage and sintered into RE functional ceramics with high far infrared emission features. Then the far infrared functional ceramics are used to interact with water. The influence of the ceramics on the physical parameters of water is investigated, and the effect of the activated water on the growth of Bel-7402 hepatoma cells cultured in vitro is further studied. The results indicate that, compared with the raw water, the water activated by the ceramics can inhibit the proliferation of hepatoma cells, with statistical probability P ceramics has a higher concentration of H+, which decreases the potential difference across the cell membrane to release the apoptosis inducing factor (AIF). After entering the cells, the activated water stimulates the mitochondria to produce immune substances that lead tumor cells to apoptosis.

  20. Downregulation of cell division cycle 25 homolog C reduces the radiosensitivity and proliferation activity of esophageal squamous cell carcinoma.

    Science.gov (United States)

    Yin, Yachao; Dou, Xiaoyan; Duan, Shimiao; Zhang, Lei; Xu, Quanjing; Li, Hongwei; Li, Duojie

    2016-09-30

    Radiation therapy is one of the most important methods of contemporary cancer treatment. Cells in the G2 and M phases are more sensitive to radiation therapy, and cell division cycle 25 homolog C (CDC25C) is essential in shifting the cell cycle between these two phases. In this study, the knockdown of CDC25C in human esophageal squamous carcinoma EC9706 cells was mediated by transfecting shRNA against human CDC25C-subcloning into pGV248. The levels of CDC25C mRNA and protein expression were assessed by reverse transcription-polymerase chain reaction (RT-PCR) and western blotting, respectively. Moreover, cell proliferation and radiosensitivity were measured. Stable CDC25C-knockdown EC9706 cell lines were successfully established. Furthermore, the proliferation of both control and CDC25C-shRNA-EC9706 cells was inhibited after the cells were treated with increasing X-ray doses, and the proliferation of the control cells was affected more significantly (p<0.05). Moreover, cell colony formation assays allowed us to reach the same conclusion. Taken together, our experiments demonstrated that the knockdown of CDC25C can reduce both the radiotherapy sensitivity and the proliferation activity of EC9706 cells. Thus, CDC25C might be a potential biomarker for radiotherapy treatment. PMID:27188256

  1. Cationic chlorophyl derivatives with SOD mimicking activity suppress the proliferation of human ovarian cancer cells.

    Science.gov (United States)

    Kobayashi, Y; Maniki, M; Nakamura, K

    1996-06-01

    Derivatives of chlorophyl, e.g. Fe-chlorin e6-Na, alpha, beta, gamma, delta-Tetraphenylporphine-tetrasulfonic acid disulfonic acid salt tetrahydrate (Fe-TPPTS) and alpha, beta, gamma, delta-Tetrakis (4-N-trimethylaminophenyl) porphine, tetra (p-toluensulfonate (Fe-TTMAPP), express SOD mimicking activity. Examination was made of suppressive effects of human cancer cell lines by derivatives of chlorophyl. Fe-TPPTS and Fe-TTMAPP suppressed proliferation of the human ovarian cancer cell lines but Fe-chlorin e6-Na failed to suppress the proliferation. Lipid peroxide was increased by application of Fe-TPPTS and Fe-TTMAPP, but decreased by application of Fe-chlorin e6-Na. SOD activity of the cancer cells did not change by application of these drugs. TPPTS and TTMAPP have a cationic charge but Fe-chlorin e6-Na has an anionic charge. It is suggested that charge of these drugs relates to the suppressive effects of the cancer cell proliferation. PMID:10851538

  2. FGF8 activates proliferation and migration in mouse post-natal oligodendrocyte progenitor cells.

    Directory of Open Access Journals (Sweden)

    Pablo Cruz-Martinez

    Full Text Available Fibroblast growth factor 8 (FGF8 is a key molecular signal that is necessary for early embryonic development of the central nervous system, quickly disappearing past this point. It is known to be one of the primary morphogenetic signals required for cell fate and survival processes in structures such as the cerebellum, telencephalic and isthmic organizers, while its absence causes severe abnormalities in the nervous system and the embryo usually dies in early stages of development. In this work, we have observed a new possible therapeutic role for this factor in demyelinating disorders, such as leukodystrophy or multiple sclerosis. In vitro, oligodendrocyte progenitor cells were cultured with differentiating medium and in the presence of FGF8. Differentiation and proliferation studies were performed by immunocytochemistry and PCR. Also, migration studies were performed in matrigel cultures, where oligodendrocyte progenitor cells were placed at a certain distance of a FGF8-soaked heparin bead. The results showed that both migration and proliferation was induced by FGF8. Furthermore, a similar effect was observed in an in vivo demyelinating mouse model, where oligodendrocyte progenitor cells were observed migrating towards the FGF8-soaked heparin beads where they were grafted. In conclusion, the results shown here demonstrate that FGF8 is a novel factor to induce oligodendrocyte progenitor cell activation, migration and proliferation in vitro, which can be extrapolated in vivo in demyelinated animal models.

  3. Impaired telomerase activity hinders proliferation and in vitro transformation of Penaeus monodon lymphoid cells.

    Science.gov (United States)

    Jayesh, P; Vrinda, S; Priyaja, P; Philip, Rosamma; Singh, I S Bright

    2016-08-01

    Retaining terminal transferase activity of telomerase, the ribonucleoprotein enzyme which add telomeric repeats on chromosome end is thought to be required to prevent cellular ageing. Additionally, telomerase considered as a marker for cell proliferation and immortalization in eukaryotes. We examined telomerase activity in tissues and lymphoid cell culture of Penaeus monodon. Along with telomerase activity, telomere repeats and an attempt on identification of telomerase reverse transcriptase (PmTERT) were made. Telomeric repeat amplification protocol revealed that telomerase-dependent telomeric lengthening has been taking place in P. monodon and the adult tissues were retaining this capacity throughout their lifespan with the highest activity in ovary, testis and lymphoid organ. However, telomerase activity could not be detected in lymphoid cells in culture. The canonical telomeric repeats added by telomerase of lymphoid tissue extract were identified as TTAGG, but pentameric repeats GGTTA and AGGTT were also added by the telomerase. PmTERT protein sequence (partial) shared 100 % identity with the TERT sequence of Daphnia pulex, 27 % sequence identity with Purple sea urchin and 24-25 % with Zebra fish. Undetectable telomerase activity in lymphoid cell culture supports the hypothesis that the inadequate telomerase activity or gene expression may be a reason that prevents neoplastic transformation and spontaneous immortalization of the cells in vitro. Thus, it is envisaged that telomerase activation in lymphoid cells may surmount cellular ageing for in vitro transformation and cell line establishment. PMID:26084784

  4. Impaired telomerase activity hinders proliferation and in vitro transformation of Penaeus monodon lymphoid cells.

    Science.gov (United States)

    Jayesh, P; Vrinda, S; Priyaja, P; Philip, Rosamma; Singh, I S Bright

    2016-08-01

    Retaining terminal transferase activity of telomerase, the ribonucleoprotein enzyme which add telomeric repeats on chromosome end is thought to be required to prevent cellular ageing. Additionally, telomerase considered as a marker for cell proliferation and immortalization in eukaryotes. We examined telomerase activity in tissues and lymphoid cell culture of Penaeus monodon. Along with telomerase activity, telomere repeats and an attempt on identification of telomerase reverse transcriptase (PmTERT) were made. Telomeric repeat amplification protocol revealed that telomerase-dependent telomeric lengthening has been taking place in P. monodon and the adult tissues were retaining this capacity throughout their lifespan with the highest activity in ovary, testis and lymphoid organ. However, telomerase activity could not be detected in lymphoid cells in culture. The canonical telomeric repeats added by telomerase of lymphoid tissue extract were identified as TTAGG, but pentameric repeats GGTTA and AGGTT were also added by the telomerase. PmTERT protein sequence (partial) shared 100 % identity with the TERT sequence of Daphnia pulex, 27 % sequence identity with Purple sea urchin and 24-25 % with Zebra fish. Undetectable telomerase activity in lymphoid cell culture supports the hypothesis that the inadequate telomerase activity or gene expression may be a reason that prevents neoplastic transformation and spontaneous immortalization of the cells in vitro. Thus, it is envisaged that telomerase activation in lymphoid cells may surmount cellular ageing for in vitro transformation and cell line establishment.

  5. Persistent STAT3 Activation in Colon Cancer Is Associated with Enhanced Cell Proliferation and Tumor Growth

    Directory of Open Access Journals (Sweden)

    Florian M. Corvinus

    2005-06-01

    Full Text Available Colorectal carcinoma (CRC is a major cause of morbidity and mortality in Western countries. It has so far been molecularly defined mainly by alterations of the Wnt pathway. We show here for the first time that aberrant activities of the signal transducer and activator of transcription STAT3 actively contribute to this malignancy and, thus, are a potential therapeutic target for CRC. Constitutive STAT3 activity was found to be abundant in dedifferentiated cancer cells and infiltrating lymphocytes of CRC samples, but not in non-neoplastic colon epithelium. Cell lines derived from malignant colorectal tumors lost persistent STAT3 activity in culture. However, implantation of colon carcinoma cells into nude mice resulted in restoration of STAT3 activity, suggesting a role of an extracellular stimulus within the tumor microenvironment as a trigger for STAT activation. STAT3 activity in CRC cells triggered through interleukin-6 or through a constitutively active STAT3 mutant promoted cancer cell multiplication, whereas STAT3 inhibition through a dominant-negative variant impaired IL-6-driven proliferation. Blockade of STAT3 activation in CRCderived xenograft tumors slowed down their development, arguing for a contribution of STAT3 to colorectal tumor growth.

  6. Recombinant interleukin 2 stimulates in vivo proliferation of adoptively transferred lymphokine-activated killer (LAK) cells

    International Nuclear Information System (INIS)

    The authors previously reported that the adoptive transfer of lymphokine-activated killer (LAK) cells plus repetitive injections of recombinant interleukin 2 (IL 2) produced a marked reduction in established pulmonary metastases from a variety of murine sarcomas. The requirement for the exogenous administration of IL 2 prompted a subsequent examination of the role of IL 2 in the in vivo function of transferred LAK cells. The in vivo proliferation and migration patterns of lymphoid cells in C57BL/6 mice were examined after i.v. transfer of LAK cells alone, i.p. injection of IL 2 alone, or the combination of LAK cells and IL 2. A model for in vivo labeling of the DNA of dividing cells was used in which mice were injected with 5-[125I]-iodo-2'-deoxyuridine (125IUdR) and, 20 hr later, their tissues were removed and were counted in a gamma analyzer. A proliferation index (PI) was calculated by dividing the mean cpm of organs of experimentally treated mice by the mean cpm of organs of control mice. In animals given LAK cells alone, the lungs and liver demonstrated little if any uptake of 125IUdR above saline-treated controls, whereas the same organs of mice receiving 6000 U of IL 2 alone displayed higher radiolabel incorporation. When mice were given LAK cells plus 6000 U of IL 2, their tissues showed an additional increase in 125IUdR uptake

  7. Different mechanisms must be considered to explain the increase in hippocampal neural precursor cell proliferation by physical activity

    Directory of Open Access Journals (Sweden)

    Rupert W Overall

    2016-08-01

    Full Text Available The number of proliferating neural precursor cells in the adult hippocampus is strongly increased by physical activity. The mechanisms through which this behavioral stimulus induces cell proliferation, however, are not yet understood. In fact, even the mode of proliferation of the stem and progenitor cells is not exactly known. Evidence exists for several mechanisms including cell cycle shortening, reduced cell death and stem cell recruitment, but as yet no model can account for all observations. An appreciation of how the cells proliferate, however, is crucial to our ability to model the neurogenic process and predict its behavior in response to pro-neurogenic stimuli. In a recent study, we addressed modulation of the cell cycle length as one possible mode of regulation of precursor cell proliferation in running mice. Our results indicated that the observed increase in number of proliferating cells could not be explained through a shortening of the cell cycle. We must therefore consider other mechanisms by which physical activity leads to enhanced precursor cell proliferation. Here we review the evidence for and against several different hypotheses and discuss the implications for future research in the field.

  8. Different Mechanisms Must Be Considered to Explain the Increase in Hippocampal Neural Precursor Cell Proliferation by Physical Activity

    Science.gov (United States)

    Overall, Rupert W.; Walker, Tara L.; Fischer, Tim J.; Brandt, Moritz D.; Kempermann, Gerd

    2016-01-01

    The number of proliferating neural precursor cells in the adult hippocampus is strongly increased by physical activity. The mechanisms through which this behavioral stimulus induces cell proliferation, however, are not yet understood. In fact, even the mode of proliferation of the stem and progenitor cells is not exactly known. Evidence exists for several mechanisms including cell cycle shortening, reduced cell death and stem cell recruitment, but as yet no model can account for all observations. An appreciation of how the cells proliferate, however, is crucial to our ability to model the neurogenic process and predict its behavior in response to pro-neurogenic stimuli. In a recent study, we addressed modulation of the cell cycle length as one possible mode of regulation of precursor cell proliferation in running mice. Our results indicated that the observed increase in number of proliferating cells could not be explained through a shortening of the cell cycle. We must therefore consider other mechanisms by which physical activity leads to enhanced precursor cell proliferation. Here we review the evidence for and against several different hypotheses and discuss the implications for future research in the field. PMID:27536215

  9. Inhibition of T cell proliferation by selective block of Ca(2+)-activated K(+) channels

    DEFF Research Database (Denmark)

    Jensen, B S; Odum, Niels; Jorgensen, N K;

    1999-01-01

    T lymphocytes express a plethora of distinct ion channels that participate in the control of calcium homeostasis and signal transduction. Potassium channels play a critical role in the modulation of T cell calcium signaling, and the significance of the voltage-dependent K channel, Kv1.3, is well...... established. The recent cloning of the Ca(2+)-activated, intermediate-conductance K(+) channel (IK channel) has enabled a detailed investigation of the role of this highly Ca(2+)-sensitive K(+) channel in the calcium signaling and subsequent regulation of T cell proliferation. The role IK channels play in T...

  10. Hedgehog signal activation coordinates proliferation and differentiation of fetal liver progenitor cells

    Energy Technology Data Exchange (ETDEWEB)

    Hirose, Yoshikazu [Laboratory of Cell Growth and Differentiation, Institute of Molecular and Cellular Biosciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-0032 (Japan); Itoh, Tohru, E-mail: itohru@iam.u-tokyo.ac.jp [Laboratory of Cell Growth and Differentiation, Institute of Molecular and Cellular Biosciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-0032 (Japan); Miyajima, Atsushi [Laboratory of Cell Growth and Differentiation, Institute of Molecular and Cellular Biosciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-0032 (Japan)

    2009-09-10

    Hedgehog (Hh) signaling plays crucial roles in development and homeostasis of various organs. In the adult liver, it regulates proliferation and/or viability of several types of cells, particularly under injured conditions, and is also implicated in stem/progenitor cell maintenance. However, the role of this signaling pathway during the normal developmental process of the liver remains elusive. Although Sonic hedgehog (Shh) is expressed in the ventral foregut endoderm from which the liver derives, the expression disappears at the onset of the liver bud formation, and its possible recurrence at the later stages has not been investigated. Here we analyzed the activation and functional relevance of Hh signaling during the mouse fetal liver development. At E11.5, Shh and an activation marker gene for Hh signaling, Gli1, were expressed in Dlk{sup +} hepatoblasts, the fetal liver progenitor cells, and the expression was rapidly decreased thereafter as the development proceeded. In the culture of Dlk{sup +} hepatoblasts isolated from the E11.5 liver, activation of Hh signaling stimulated their proliferation and this effect was cancelled by a chemical Hh signaling inhibitor, cyclopamine. In contrast, hepatocyte differentiation of Dlk{sup +} hepatoblasts in vitro as manifested by the marker gene expression and acquisition of ammonia clearance activity was significantly inhibited by forced activation of Hh signaling. Taken together, these results demonstrate the temporally restricted manner of Hh signal activation and its role in promoting the hepatoblast proliferation, and further suggest that the pathway needs to be shut off for the subsequent hepatic differentiation of hepatoblasts to proceed normally.

  11. Statins meditate anti-atherosclerotic action in smooth muscle cells by peroxisome proliferator-activated receptor-γ activation

    Energy Technology Data Exchange (ETDEWEB)

    Fukuda, Kazuki [Department of Metabolic Medicine, Faculty of Life Sciences, Kumamoto University, Kumamoto (Japan); Matsumura, Takeshi, E-mail: takeshim@gpo.kumamoto-u.ac.jp [Department of Metabolic Medicine, Faculty of Life Sciences, Kumamoto University, Kumamoto (Japan); Senokuchi, Takafumi; Ishii, Norio; Kinoshita, Hiroyuki; Yamada, Sarie; Murakami, Saiko [Department of Metabolic Medicine, Faculty of Life Sciences, Kumamoto University, Kumamoto (Japan); Nakao, Saya [Department of Environmental & Symbiotic Sciences, Prefectural University of Kumamoto, Kumamoto (Japan); Motoshima, Hiroyuki; Kondo, Tatsuya; Kukidome, Daisuke; Kawasaki, Shuji [Department of Metabolic Medicine, Faculty of Life Sciences, Kumamoto University, Kumamoto (Japan); Kawada, Teruo [Laboratory of Nutrition Chemistry, Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Kyoto (Japan); Nishikawa, Takeshi; Araki, Eiichi [Department of Metabolic Medicine, Faculty of Life Sciences, Kumamoto University, Kumamoto (Japan)

    2015-01-30

    Highlights: • Statins induce PPARγ activation in vascular smooth muscle cells. • Statin-induced PPARγ activation is mediated by COX-2 expression. • Statins suppress cell migration and proliferation in vascular smooth muscle cells. • Statins inhibit LPS-induced inflammatory responses by PPARγ activation. • Fluvastatin suppress the progression of atherosclerosis and induces PPARγ activation in the aorta of apoE-deficient mice. - Abstract: The peroxisome proliferator-activated receptor-γ (PPARγ) is an important regulator of lipid and glucose metabolism, and its activation is reported to suppress the progression of atherosclerosis. We have reported that 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins) activate PPARγ in macrophages. However, it is not yet known whether statins activate PPARγ in other vascular cells. In the present study, we investigated whether statins activate PPARγ in smooth muscle cells (SMCs) and endothelial cells (ECs) and thus mediate anti-atherosclerotic effects. Human aortic SMCs (HASMCs) and human umbilical vein ECs (HUVECs) were used in this study. Fluvastatin and pitavastatin activated PPARγ in HASMCs, but not in HUVECs. Statins induced cyclooxygenase-2 (COX-2) expression in HASMCs, but not in HUVECs. Moreover, treatment with COX-2-siRNA abrogated statin-mediated PPARγ activation in HASMCs. Statins suppressed migration and proliferation of HASMCs, and inhibited lipopolysaccharide-induced expression of monocyte chemoattractant protein-1 (MCP-1) and tumor necrosis factor-α (TNF-α) in HASMCs. These effects of statins were abrogated by treatment with PPARγ-siRNA. Treatment with statins suppressed atherosclerotic lesion formation in Apoe{sup −/−} mice. In addition, transcriptional activity of PPARγ and CD36 expression were increased, and the expression of MCP-1 and TNF-α was decreased, in the aorta of statin-treated Apoe{sup −/−} mice. In conclusion, statins mediate anti-atherogenic effects

  12. Low Dose Cadmium Inhibits Proliferation of Human Renal Mesangial Cells via Activation of the JNK Pathway

    Science.gov (United States)

    Chen, Xiaocui; Li, Jing; Cheng, Zuowang; Xu, Yinghua; Wang, Xia; Li, Xiaorui; Xu, Dongmei; Kapron, Carolyn M.; Liu, Ju

    2016-01-01

    Cadmium (Cd) is a heavy metal and environmental pollutant. The kidney is the principal target organ of Cd exposure. Previously, we found that low concentration of Cd damages the integrity of the glomerular filtration barrier. However, little is known about the effects of Cd on renal mesangial cells, which provide structural support for the glomerular capillary loops and regulate intraglomerular blood flow. In this study, human renal mesangial cells (HRMCs) were cultured in the presence of serum and treated with 4 μM Cd. We found that Cd activates the c-Jun N-terminal kinase (JNK) pathway, and increases the protein levels of c-Jun and c-Fos. Cd treatment also induces a decrease in proliferation and an increase in apoptosis of HRMCs, but only the decrease in HRMC proliferation was reversed by pretreatment with SP600125, an inhibitor of the JNK pathway. In addition, Cd does not change the expression of α-smooth muscle actin and platelet-derived growth factor receptor-β, the markers of mesangial cells, or the alignment of the filamentous actin (F-actin) cytoskeleton of HRMCs. Our data indicate that the JNK pathway mediates the inhibitory effects of Cd on HRMC proliferation. PMID:27739415

  13. Peroxisome proliferator-activated receptor γ ligands induce cell cycle arrest and apoptosis in human renal carcinoma cell lines

    Institute of Scientific and Technical Information of China (English)

    Feng-guang YANG; Zhi-wen ZHANG; Dian-qi XIN; Chang-jin SHI; Jie-ping WU; Ying-lu GUO; You-fei GUAN

    2005-01-01

    Aim: To study the effect of peroxisome proliferator-actived receptor γ (PPARγ)ligands on cell proliferation and apoptosis in human renal carcinoma cell lines.Methods: The expression of PPARγ was investigated by reverse transcriptase polymerase chain reaction (RT-PCR), Western blot and immunohistochemistry.The effect of thiazolidinedione (TZD) PPARγ ligands on growth of renal cell carcinoma (RCC) cells was measured by MTT assay and flow cytometric analysis. Cell death ELISA, Hoechst 33342 fluorescent staining and DNA ladder assay were used to observe the effects of PPARγ ligands on apoptosis. Regulatory proteins of cell cycle and apoptosis were detected by Western blot analysis. Results:PPARγ was expressed at much higher levels in renal tumors than in the normal kidney (2.16±0.85 vs 0.90±0.73; P<0.01 ). TZD PPARγ ligands inhibited RCC cell growth in a dose-dependent manner with IC50 values of 7.08 μmol/L and 11.32 μmol/L for pioglitazone, and 5.71 μmol/L and 8.38 μmol/L for troglitazone in 786-O and A498 cells, respectively. Cell cycle analysis showed a G0/G1 arrest in human RCC cells following 24-h exposure to TZD. Analysis of cell cycle regulatory proteins revealed that TZD decreased the protein levels of proliferating cell nuclear antigen, pRb, cyclin D1, and Cdk4 but increased the levels of p21 and p27 in a timedependent manner. Furthermore, high doses of TZD induced massive apoptosis in renal cancer cells, with increased Bax expression and decreased Bcl-2 expression.Conclusion: TZD PPARγ ligands showed potent inhibitory effect on proliferation,and could induce apoptosis in RCC cells. These results suggest that ligands for PPARγ have potential antitumor effects on renal carcinoma cells.

  14. Pharmacological AMP kinase activators target the nucleolar organization and control cell proliferation.

    Directory of Open Access Journals (Sweden)

    Mohamed Kodiha

    Full Text Available AIMS: Phenformin, resveratrol and AICAR stimulate the energy sensor 5'-AMP activated kinase (AMPK and inhibit the first step of ribosome biogenesis, de novo RNA synthesis in nucleoli. Nucleolar activities are relevant to human health, because ribosome production is crucial to the development of diabetic complications. Although the function of nucleoli relies on their organization, the impact of AMPK activators on nucleolar structures is not known. Here, we addressed this question by examining four nucleolar proteins that are essential for ribosome biogenesis. METHODS: Kidney cells were selected as model system, because diabetic nephropathy is one of the complications associated with diabetes mellitus. To determine the impact of pharmacological agents on nucleoli, we focused on the subcellular and subnuclear distribution of B23/nucleophosmin, fibrillarin, nucleolin and RPA194. This was achieved by quantitative confocal microscopy at the single-cell level in combination with cell fractionation and quantitative Western blotting. RESULTS: AMPK activators induced the re-organization of nucleoli, which was accompanied by changes in cell proliferation. Among the compounds tested, phenformin and resveratrol had the most pronounced impact on nucleolar organization. For B23, fibrillarin, nucleolin and RPA194, both agents (i altered the nucleocytoplasmic distribution and nucleolar association and (ii reduced significantly the retention in the nucleus. (iii Phenformin and resveratrol also increased significantly the total concentration of B23 and nucleolin. CONCLUSIONS: AMPK activators have unique effects on the subcellular localization, nuclear retention and abundance of nucleolar proteins. We propose that the combination of these events inhibits de novo ribosomal RNA synthesis and modulates cell proliferation. Our studies identified nucleolin as a target that is especially sensitive to pharmacological AMPK activators. Because of its response to

  15. The role of peroxisome proliferator-activated receptor-β/δ in epidermal growth factor-induced HaCaT cell proliferation

    International Nuclear Information System (INIS)

    Epidermal growth factor (EGF) has been shown to be a potent mitogen for epidermal cells both in vitro and in vivo, thus contributing to the development of an organism. It has recently become clear that peroxisome proliferator-activated receptor-β/δ (PPARβ/δ) expression and activation is involved in the cell proliferation. However, little is known about the role of PPARβ/δ in EGF-induced proliferation of HaCaT keratinocytes. In this study, HaCaT cells were cultured in the presence and absence of EGF and we identified that EGF induced an increase of PPARβ/δ mRNA and protein level expression in time-dependent and dose-dependent manner, and AG1487, an EGF receptor (EGFR) special inhibitor, caused attenuation of PPARβ/δ protein expression. Electrophoretic mobility shift assay (EMSA) revealed that EGF significantly increased PPARβ/δ binding activity in HaCaT keratinocytes. Antisense phosphorothioate oligonucleotides (asODNs) against PPARβ/δ caused selectively inhibition of PPARβ/δ protein content induced by EGF and significantly attenuated EGF-mediated cell proliferation. Treatment of the cells with L165041, a specific synthetic ligand for PPARβ/δ, significantly enhanced EGF-mediated cell proliferation. Finally, c-Jun ablation inhibited PPARβ/δ up-regulation induced by EGF, and chromatin immunoprecipitation (ChIP) showed that c-Jun bound to the PPARβ/δ promoter and the binding increased in EGF-stimulated cells. These results demonstrate that EGF induces PPARβ/δ expression in a c-Jun-dependent manner and PPARβ/δ plays a vital role in EGF-stimulated proliferation of HaCaT cells

  16. Hepatocyte growth factor-induced proliferation of hepatic stem-like cells depends on activation of NF-κB

    Institute of Scientific and Technical Information of China (English)

    PengYao; YiqunZhan; WangxiangXu; ChangyanLi; PeibinYue; ChengwangXu; DarongHU; ChengkuiQu; XiaomingYang

    2005-01-01

    Background/Aims: Hepatocyte growth factor (HGF) regulates proliferation of hepatic stem cells. Transcription factor nuclear factor kappa B (NF-κB) has been demonstrated as a key mediator for cell growth regulation. We investigated the role of NF-κB in HGF-mediated cellular proliferation responses in a rat liver.derived hepatic stem-like cell line WB.F344. Methods: Cell proliferation was determined by incorporation of [3H]thymidine. Phosphorylation of ERK1/2, p38 MAPK, Akt and IκBα by HGF stimulation was detected by Western blotting. NF-κB activation was determined by electrophoretic mobility shift assay and NF-κB.mediated SEAP reporter assay. NF-κB activation was inhibited by treatment with an IκBα dominant-negative vector or inhibitor BAY-11-7082. Results: We found that stimulation of WB-F344 cells with HGF promoted cell proliferation and effectively protected WB-F344 cells from apoptosis induced by TNF-α. We also observed activation of ERK1/2, p38 MAPK, Akt and NF-κB signaling pathways by HGF in WB-F344 cells. HGF-induced cell proliferation was partly blocked by pre-treatment of the cells with inhibitors against MEK1 or p38 MAPK, and completely blocked using an inhibitor for NF-κB activity.Furthermore, it was demonstrated that IκB mutant that suppressed NF-κB activity completely blocked HGF-induced cell proliferation. Conclusions: NF-κB activity is required for HGF-induced proliferation in hepatic stem-like cell line WB-F344, and this activity requires ERK1/2 and p38 MAPK pathways.

  17. Peroxisome Proliferator-Activated Receptor and Vitamin D Receptor Signaling Pathways in Cancer Cells

    Energy Technology Data Exchange (ETDEWEB)

    Matsuda, Satoru, E-mail: smatsuda@cc.nara-wu.ac.jp; Kitagishi, Yasuko [Department of Food Science and Nutrition, Nara Women’s University, Kita-Uoya Nishimachi, Nara 630-8506 (Japan)

    2013-10-21

    Peroxisome proliferator-activated receptors (PPARs) are members of the superfamily of nuclear hormone receptors, which respond to specific ligands such as polyunsaturated fatty acids by altering gene expression. Three subtypes of this receptor have been discovered, each evolving to achieve different biological functions. Like other nuclear receptors, the transcriptional activity of PPARs is affected not only by ligand-stimulation, but also by cross-talk with other molecules. For example, both PPARs and the RXRs are ligand-activated transcription factors that coordinately regulate gene expression. In addition, PPARs and vitamin D receptor (VDR) signaling pathways regulate a multitude of genes that are of importance for cellular functions including cell proliferation and cell differentiation. Interaction of the PPARs and VDR signaling pathways has been shown at the level of molecular cross-regulation of their transcription factor. A variety of ligands influencing the PPARs and VDR signaling pathways have been shown to reveal chemopreventive potential by mediating tumor suppressive activities in human cancers. Use of these compounds may represent a potential novel strategy to prevent cancers. This review summarizes the roles of the PPARs and the VDR in pathogenesis and progression of cancer.

  18. Peroxisome Proliferator-Activated Receptor and Vitamin D Receptor Signaling Pathways in Cancer Cells

    International Nuclear Information System (INIS)

    Peroxisome proliferator-activated receptors (PPARs) are members of the superfamily of nuclear hormone receptors, which respond to specific ligands such as polyunsaturated fatty acids by altering gene expression. Three subtypes of this receptor have been discovered, each evolving to achieve different biological functions. Like other nuclear receptors, the transcriptional activity of PPARs is affected not only by ligand-stimulation, but also by cross-talk with other molecules. For example, both PPARs and the RXRs are ligand-activated transcription factors that coordinately regulate gene expression. In addition, PPARs and vitamin D receptor (VDR) signaling pathways regulate a multitude of genes that are of importance for cellular functions including cell proliferation and cell differentiation. Interaction of the PPARs and VDR signaling pathways has been shown at the level of molecular cross-regulation of their transcription factor. A variety of ligands influencing the PPARs and VDR signaling pathways have been shown to reveal chemopreventive potential by mediating tumor suppressive activities in human cancers. Use of these compounds may represent a potential novel strategy to prevent cancers. This review summarizes the roles of the PPARs and the VDR in pathogenesis and progression of cancer

  19. Cell Proliferation in Neuroblastoma

    Directory of Open Access Journals (Sweden)

    Laura L. Stafman

    2016-01-01

    Full Text Available Neuroblastoma, the most common extracranial solid tumor of childhood, continues to carry a dismal prognosis for children diagnosed with advanced stage or relapsed disease. This review focuses upon factors responsible for cell proliferation in neuroblastoma including transcription factors, kinases, and regulators of the cell cycle. Novel therapeutic strategies directed toward these targets in neuroblastoma are discussed.

  20. MicroRNA-130b promotes cell proliferation and invasion by inhibiting peroxisome proliferator-activated receptor-γ in human glioma cells.

    Science.gov (United States)

    Gu, Jian-Jun; Zhang, Jian-He; Chen, Hong-Jie; Wang, Shou-Sen

    2016-06-01

    MicroRNA-130b (miR-130b) is a novel tumor-related miRNA that has been found to be involved in several biological processes. However, there is limited evidence regarding the role of miR-130b in the tumorigenesis of human gliomas. In the present study, reverse transcription-quantitative polymerase chain reaction (RT-qPCR) assays were used to quantify miR-130b expression levels in human glioma tissues and glioma cell lines (U251, U87, SNB19 and LN229). The expression level of miR-130b was found to be markedly higher in human glioma tissues than in non‑neoplastic brain specimens. Specifically, higher expression levels of miR‑130b were observed in the glioma cell lines, compared with those in normal human astrocytes (NHA). We also confirmed that miR‑130b interacted with the 3'-untranslated region of peroxisome proliferator‑activated receptor-γ (PPAR‑γ), which negatively affected the protein levels of E-cadherin. Furthermore, its effects on cell proliferation and invasion were examined using CCK8, colony formation, cell cycle and Transwell assays. We found that the upregulation of miR-130b induced cell proliferation, decreased the percentage of cells in the G0/G1 phase and enhanced the invasiveness of U251 glioma cells whereas the downregulation of miR-130b exerted opposing effects. Moreover, it was demonstrated that the downregulation of miR‑130b in U251 glioma cells restored the expression of PPAR-γ and E-cadherin, and inhibited the expression of β-catenin. Notably, PPAR-γ knockdown abolished the inhibitory effect of miR-130b inhibitor on the proliferation and invasivness of U251 cells. Taken together, these findings suggest that miR‑130b promotes the proliferation and invasion of U251 glioma cells by inhibiting PPAR-γ.

  1. Sonic hedgehog stimulates glycolysis and proliferation of breast cancer cells: Modulation of PFKFB3 activation

    Energy Technology Data Exchange (ETDEWEB)

    Ge, Xin; Lyu, Pengwei; Gu, Yuanting; Li, Lin; Li, Jingruo; Wang, Yan; Zhang, Linfeng [Department of Breast Surgery, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, Henan (China); Fu, Chao [Department of Ultrasonography, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, Henan (China); Cao, Zhang, E-mail: zzzhangcao@126.com [Department of Breast Surgery, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, Henan (China)

    2015-08-28

    Sonic hesgehog (Shh) signaling has been reported to play an essential role in cancer progression. The mechanism of Shh involved in breast cancer carcinogenesis remains unclear. The present study sought to explore whether Shh signaling could regulate the glycolytic metabolism in breast cancers. Overexpression of the smoothed (Smo) and Gli-1 was found in human primary breast cancers. The expressions of Shh and Gli-1 correlated significantly with tumor size and tumor stage. In vitro, human recombinant Shh (rShh) triggered Smo and Gli-1 expression, promoted glucose utilization and lactate production, and accelerated cell proliferation in MCF-7 and MDA-MB-231 cells. Notably, rShh did not alter 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase 3 (PFKFB3) expression but augmented PFKFB3 phosphorylation on ser{sup 461}, along with elevated fructose-2,6-bisphosphate (F2,6BP) generation by MCF-7 and MDA-MB-231 cells. This effect could be dampened by Smo siRNA but not by Gli-1 siRNA. In addition, our data showed the upregulated expressions of MAPK by rShh and elevatory PFKFB3 phosphorylation by p38/MAPK activated kinase (MK2). In conclusion, our study characterized a novel role of Shh in promoting glycolysis and proliferation of breast cancer cells via PFKFB3 phosphorylation, which was mediated by Smo and p38/MK2. - Highlights: • Overexpression of Smo and Gli-1 was found in human primary breast cancers. • Shh promoted glucose utilization, lactate production, and cell proliferation. • Shh did not alter PFKFB3 expression but augmented PFKFB3 phosphorylation on ser461. • Shh acts on PFKFB3 phosphorylation via Smo and p38 MAPK/MK2.

  2. FBI-1 enhances ETS-1 signaling activity and promotes proliferation of human colorectal carcinoma cells.

    Directory of Open Access Journals (Sweden)

    Min Zhu

    Full Text Available In this study, we investigated a potential regulatory role of FBI-1 in transcription factor activity of ETS-1. The protein interaction was identified between ETS-1 and FBI-1 in lovo cells. The accumulating data showed that FBI-1 promoted the recruitment of ETS-1 to endogenous promoter of its target genes and increase ETS-1 accumulation in the nuclear. Our work also indicated that the FBI-1 enhances ETS-1 transcription factor activity via down-regulating p53-mediated inhibition on ETS-1. Further, FBI-1 plays a role in regulation of colorectal carcinoma cells proliferation. These findings supported that FBI-1 might be a potential molecule target for treating colorectal carcinoma.

  3. Proliferating cell nuclear antigen (PCNA) activity in hepatocellular carcinoma, benign peri-neoplastic and normal liver.

    Science.gov (United States)

    Mun, Kein-Seong; Cheah, Phaik-Leng; Baharudin, Nurul Bahiyah; Looi, Lai-Meng

    2006-12-01

    Hepatocellular carcinoma (HCC) is among the ten most common cancers in Malaysian males. As cellular proliferation is an important feature of malignant transformation, we studied the proliferation pattern of normal and benign perineoplastic liver versus hepatocellular carcinoma in an attempt to further understand the tumour transformation process. 39 HCC (21 with accompanying and 18 without cirrhosis) histologically diagnosed at the Department of Pathology, University of Malaya Medical Centre between January 1992 and December 2003 were immunohistochemically studied using a monoclonal antibody to PCNA (Clone PC10: Dako). 20 livers from cases who had succumbed to traumatic injuries served as normal liver controls (NL). PCNA labeling index (PCNA-LI) was determined by counting the number of immunopositive cells in 1000 contiguous HCC, benign cirrhotic perineoplastic liver (BLC), benign perineoplastic non-cirrhotic (BLNC) and NL cells and conversion to a percentage. The PCNA-LI was also expressed as Ojanguren et al's grades. PCNA was expressed in 10% NL, 38.9% BLNC, 76.2% BLC and 71.8% HCC with BLNC, BLC and HCC showing significantly increased (p cells being immunopositive) immunoreactivity on Ojanguren et al's grading system and only HCC demonstrated immunoreactivity which ranged up to grade 3 (75% of cells). From this study, there appears to be a generally increasing trend of proliferative activity from NL to BLNC to BLC and HCC. Nonetheless, BLNC and BLC, like NL, retained low PCNA-LI and only HCC had a significantly increased PCNA-LI compared with the benign categories. This is probably related to the malignant nature of HCC and may reflect the uncontrolled proliferation of the neoplastic hepatocytes. PMID:18376794

  4. Colchicum autumnale agglutinin activates all murine T-lymphocytes but does not induce the proliferation of all activated cells.

    Science.gov (United States)

    Bemer, V; Van Damme, E J; Peumans, W J; Perret, R; Truffa-Bachi, P

    1996-08-25

    Plant lectins with mitogenic properties for T-lymphocytes have been particularly useful for the study of T-cell activation and effector functions. In the search for mitogenic lectins possessing activation features different from the ones associated with the already known mitogens, we found that an agglutinin isolated from Colchicum autumnale tubers, Colchicum autumnale agglutinin (CAA), possesses interesting properties. First, contrasting with the classical mitogens, CAA induces the proliferation of a fraction of the CD4+ and CD8+ mouse T-lymphocytes. Second, the CAA-induced proliferation requires MHC class II and CD4 molecules. Third, although only a fraction of T-cells enters into the cell cycle, all T-lymphocytes are activated and express high levels of the activation markers CD69 and CD44. Finally, CAA-stimulation is characterized by a particular pattern of the cytokine gene expression, reflected by the transcription of the IL2, IL5, and IFN-gamma genes, while the IL4 and IL10 genes remained silent. Taken together these data demonstrate that CAA activation does not conform to the pathway of T-cell triggering observed with classical mitogenes and represents a new tool for the analysis of T-cell activation.

  5. Interleukin-1β regulates cell proliferation and activity of extracellular matrix remodelling enzymes in cultured primary pig heart cells

    International Nuclear Information System (INIS)

    Research highlights: → Levels of IL-1β are increased in the pig myocardium after infarction. → Cultured pig heart cells possess IL-1 receptors. → IL-1β increases cell proliferation of pig heart cells in-vitro. → IL-1β increases MMP-2 and MMP-9 activity in pig heart cells in-vitro. → IL-1β may be important for tissue remodelling events after myocardial infarction. -- Abstract: After myocardial infarction, elevated levels of interleukins (ILs) are found within the myocardial tissue and IL-1β is considered to play a major role in tissue remodelling events throughout the body. In the study presented, we have established a cell culture model of primary pig heart cells to evaluate the effects of different concentrations of IL-1β on cell proliferation as well as expression and activity of enzymes typically involved in tissue remodelling. Primary pig heart cell cultures were derived from three different animals and stimulated with recombinant pig IL-1β. RNA expression was detected by RT-PCR, protein levels were evaluated by Western blotting, activity of matrix metalloproteinases (MMPs) was quantified by gelatine zymography and cell proliferation was measured using colorimetric MTS assays. Pig heart cells express receptors for IL-1 and application of IL-1β resulted in a dose-dependent increase of cell proliferation (P < 0.05 vs. control; 100 ng/ml; 24 h). Gene expression of caspase-3 was increased by IL-1β (P < 0.05 vs. control; 100 ng/ml; 3 h), and pro-caspase-3 but not active caspase was detected in lysates of pig heart cells by Western blotting. MMP-2 gene expression as well as enzymatic activities of MMP-2 and MMP-9 were increased by IL-1β (P < 0.05 vs. control; 100 ng/ml; 3 h for gene expression, 48 and 72 h for enzymatic activities of MMP-2 and MMP-9, respectively). Our in vitro data suggest that IL-1β plays a major role in the events of tissue remodelling in the heart. Combined with our recently published in vivo data (Meybohm et al., PLoS One

  6. RAF kinase activity regulates neuroepithelial cell proliferation and neuronal progenitor cell differentiation during early inner ear development.

    Directory of Open Access Journals (Sweden)

    Marta Magariños

    Full Text Available BACKGROUND: Early inner ear development requires the strict regulation of cell proliferation, survival, migration and differentiation, coordinated by the concerted action of extrinsic and intrinsic factors. Deregulation of these processes is associated with embryonic malformations and deafness. We have shown that insulin-like growth factor I (IGF-I plays a key role in embryonic and postnatal otic development by triggering the activation of intracellular lipid and protein kinases. RAF kinases are serine/threonine kinases that regulate the highly conserved RAS-RAF-MEK-ERK signaling cascade involved in transducing the signals from extracellular growth factors to the nucleus. However, the regulation of RAF kinase activity by growth factors during development is complex and still not fully understood. METHODOLOGY/PRINCIPAL FINDINGS: By using a combination of qRT-PCR, Western blotting, immunohistochemistry and in situ hybridization, we show that C-RAF and B-RAF are expressed during the early development of the chicken inner ear in specific spatiotemporal patterns. Moreover, later in development B-RAF expression is associated to hair cells in the sensory patches. Experiments in ex vivo cultures of otic vesicle explants demonstrate that the influence of IGF-I on proliferation but not survival depends on RAF kinase activating the MEK-ERK phosphorylation cascade. With the specific RAF inhibitor Sorafenib, we show that blocking RAF activity in organotypic cultures increases apoptosis and diminishes the rate of cell proliferation in the otic epithelia, as well as severely impairing neurogenesis of the acoustic-vestibular ganglion (AVG and neuron maturation. CONCLUSIONS/SIGNIFICANCE: We conclude that RAF kinase activity is essential to establish the balance between cell proliferation and death in neuroepithelial otic precursors, and for otic neuron differentiation and axonal growth at the AVG.

  7. Plasminogen N-terminal activation peptide modulates the activity of angiostatin-related peptides on endothelial cell proliferation and migration.

    Science.gov (United States)

    Hayashi, Moyuru; Tamura, Yosuke; Dohmae, Naoshi; Kojima, Soichi; Shimonaka, Motoyuki

    2008-05-01

    Angiostatin, a potent inhibitor of angiogenesis, is derived from the fibrinolytic proenzyme, plasminogen, by enzymatic processing. Plasminogen N-terminal activation peptide (PAP) is one of the products concomitantly released aside from angiostatin (kringles 1-4) and mini-plasminogen (kringle 5 plus the catalytic domain) when plasminogen is processed. To determine whether PAP alone or together with the angiostatin-related peptides derived from the processing of plasminogen modulate the proliferation and motility of endothelial cells, we have generated a recombinant PAP and used it to study its effects on endothelial cells in the presence and absence of the angiostatin-related peptides. Our results showed that PAP alone slightly increased the migration but not the proliferation of endothelial cells. However, in the presence of the angiostatin-related peptides, PAP attenuated the inhibitory activity of the angiostatin-related peptides on the proliferation and migration of endothelial cells. The inhibitory effect of PAP on the angiostatin-related peptides could be due to its binding to the kringle domains of the latter peptides. PMID:18294956

  8. Plasminogen N-terminal activation peptide modulates the activity of angiostatin-related peptides on endothelial cell proliferation and migration

    International Nuclear Information System (INIS)

    Angiostatin, a potent inhibitor of angiogenesis, is derived from the fibrinolytic proenzyme, plasminogen, by enzymatic processing. Plasminogen N-terminal activation peptide (PAP) is one of the products concomitantly released aside from angiostatin (kringles 1-4) and mini-plasminogen (kringle 5 plus the catalytic domain) when plasminogen is processed. To determine whether PAP alone or together with the angiostatin-related peptides derived from the processing of plasminogen modulate the proliferation and motility of endothelial cells, we have generated a recombinant PAP and used it to study its effects on endothelial cells in the presence and absence of the angiostatin-related peptides. Our results showed that PAP alone slightly increased the migration but not the proliferation of endothelial cells. However, in the presence of the angiostatin-related peptides, PAP attenuated the inhibitory activity of the angiostatin-related peptides on the proliferation and migration of endothelial cells. The inhibitory effect of PAP on the angiostatin-related peptides could be due to its binding to the kringle domains of the latter peptides

  9. The Inhibitory Role of Lactacystin and β-Lactacystinon T-cell Activation and Proliferation

    Institute of Scientific and Technical Information of China (English)

    Peng-HongSONG; Hai-YangXIE; Shu-SenZHENG; JianWU

    2004-01-01

    To evaluate the effects of proteasome inhibitors lactacystin (LAC) and β-1actacystin (β-LAC)on the proliferation and activation of T lymphocytes, flow cytometry was used to analyze the proliferationand the expression of CD69, CD25 and CD3 of T lymphocytes activated by PHA. Furthermore, theexpressions of PA28 and IL-2 mRNA were assayed by competitive RT-PCR. The results indicated that:(1) LAC and 13-LAC significantly decreased the incomoration of BrdU and inhibited T lymohocytesoroliferation in T lymphocytes activated by PHA; (2) although LAC and β-LAC did not affect the expressionof CD69 at any time, they significantly inhibited the expression of CD25 (48 h, 72 h, P<0.05);(3) in comoarison with control, LAC and β-LAC significantly down-regulated the expression of PA28and 1L-2 mRNA (48 h, 72 h, P<0.05). LAC and β-LAC significantly inhibited the proliferation and activationof T cells. Mechanisms involved are inhibition of CD25 and down-regulation of PA28 and IL-2 mRNAexpressions.

  10. The Inhibitory Role of Lactacystin and β-Lactacystin on T-cell Activation and Proliferation

    Institute of Scientific and Technical Information of China (English)

    Peng-Hong SONG; Hai-Yang XIE; Shu-Sen ZHENG; Jian WU

    2004-01-01

    To evaluate the effects of proteasome inhibitors lactacystin (LAC) and β-lactacystin (β-LAC)on the proliferation and activation of T lymphocytes, flow cytometry was used to analyze the proliferationand the expression of CD69, CD25 and CD3 of T lymphocytes activated by PHA. Furthermore, theexpressions of PA28 and IL-2 mRNA were assayed by competitive RT-PCR. The results indicated that:(1) LAC and β-LAC significantly decreased the incorporation of BrdU and inhibited T lymphocytesproliferation in T lymphocytes activated by PHA; (2) although LAC and β-LAC did not affect the expressionof CD69 at any time, they significantly inhibited the expression of CD25 (48h, 72h, P<0.05);(3) in comparison with control, LAC and β-LAC significantly down-regulated the expression of PA28and IL-2 mRNA (48h, 72h, P<0.05). LAC and β-LAC significantly inhibited the proliferation and activationof T cells. Mechanisms involved are inhibition of CD25 and down-regulation of PA28 and IL-2 mRNAexpressions.

  11. Inhibitory Activity of Synthesized Acetylated Procyanidin B1 Analogs against HeLa S3 Cells Proliferation

    Directory of Open Access Journals (Sweden)

    Syuhei Okamoto

    2014-02-01

    Full Text Available Proanthocyanidins, also known as condensed tannins and/or oligomeric flavonoids, occur in many edible plants and have various interesting biological activities. Previously, we reported a synthetic method for the preparation of various procyanidins in pure form and described their biological activities. Here, we describe the synthesis of procyanidin B1 acetylated analogs and discuss their inhibition activities against HeLa S3 cell proliferation. Surprisingly, the lower-unit acetylated procyanidin B1 strongly inhibited the proliferation of HeLa S3 cells. This molecule showed much stronger inhibitory activity than did epigallocatechin-3-O-gallate (EGCG, green tea polyphenol, and dimeric compounds that included EGCG as a unit. This result suggests that the phenolic hydroxyl groups of the upper-units in flavan-3-ols are important for their inhibitory activity against cancer cell proliferation and that a hydrophobic lower unit dimer enhances this activity.

  12. Activation of double-stranded RNA-dependent protein kinase inhibits proliferation of pancreatic β-cells

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Shan-Shan [Key Laboratory of Human Functional Genomics of Jiangsu Province, Nanjing Medical University, Nanjing (China); Department of Biochemistry and Molecular Biology, Nanjing Medical University, Nanjing (China); Jiang, Teng [Department of Neurology, Qingdao Municipal Hospital, Nanjing Medical University, Nanjing (China); Wang, Yi; Gu, Li-Ze [Key Laboratory of Human Functional Genomics of Jiangsu Province, Nanjing Medical University, Nanjing (China); Department of Biochemistry and Molecular Biology, Nanjing Medical University, Nanjing (China); Wu, Hui-Wen [Laboratory Center for Basic Medical Sciences, Nanjing Medical University, Nanjing (China); Tan, Lan [Department of Neurology, Qingdao Municipal Hospital, Nanjing Medical University, Nanjing (China); Guo, Jun, E-mail: Guoj@njmu.edu.cn [Key Laboratory of Human Functional Genomics of Jiangsu Province, Nanjing Medical University, Nanjing (China); Department of Biochemistry and Molecular Biology, Nanjing Medical University, Nanjing (China)

    2014-01-17

    Highlights: •PKR can be activated by glucolipitoxicity and pro-inflammatory cytokines in β-cells. •Activated PKR inhibited β-cell proliferation by arresting cell cycle at G1 phase. •Activated PKR fully abrogated the pro-proliferative effects of IGF-I on β-cells. -- Abstract: Double-stranded RNA-dependent protein kinase (PKR) is revealed to participate in the development of insulin resistance in peripheral tissues in type 2 diabetes (T2DM). Meanwhile, PKR is also characterized as a critical regulator of cell proliferation. To date, no study has focused on the impact of PKR on the proliferation of pancreatic β-cells. Here, we adopted insulinoma cell lines and mice islet β-cells to investigate: (1) the effects of glucolipotoxicity and pro-inflammatory cytokines on PKR activation; (2) the effects of PKR on proliferation of pancreatic β-cells and its underlying mechanisms; (3) the actions of PKR on pro-proliferative effects of IGF-I and its underlying pathway. Our results provided the first evidence that PKR can be activated by glucolipitoxicity and pro-inflammatory cytokines in pancreatic β-cells, and activated PKR significantly inhibited cell proliferation by arresting cell cycle at G1 phase. Reductions in cyclin D1 and D2 as well as increases in p27 and p53 were associated with the anti-proliferative effects of PKR, and proteasome-dependent degradation took part in the reduction of cyclin D1 and D2. Besides, PKR activation abrogated the pro-proliferative effects of IGF-I by activating JNK and disrupting IRS1/PI3K/Akt signaling pathway. These findings indicate that the anti-proliferative actions of PKR on pancreatic β-cells may contribute to the pathogenesis of T2DM.

  13. Downregulation of Transketolase Activity Is Related to Inhibition of Hippocampal Progenitor Cell Proliferation Induced by Thiamine Deficiency

    OpenAIRE

    Yanling Zhao; Yiying Wu; Haolu Hu; Jinghui Cai; Min Ning; Xiushi Ni; Chunjiu Zhong

    2014-01-01

    In animal experiments, hippocampal neurogenesis and the activity of thiamine-dependent transketolase decrease markedly under conditions of thiamine deficiency. To further investigate the effect of thiamine deficiency on the proliferation of hippocampal progenitor cells (HPCs) and the potential mechanisms involved in this effect, we cultured HPCs in vitro in the absence of thiamine and found that proliferation and transketolase activity were both significantly repressed. Furthermore, specific ...

  14. Germ cell nuclear factor directly represses the transcription of peroxisome proliferator-activated receptor delta gene

    Institute of Scientific and Technical Information of China (English)

    Chengqiang He; Naizheng Ding; Jie Kang

    2008-01-01

    Germ cell nuclear factor (GCNF) is a transcription factor that can repress gene transcription and plays an important role during spermatogenesis. Peroxisome proliferator-activated receptor delta (PPARδ) is a nuclear hormone receptor belonging to the steroid receptor superfamily.It can activate the expression of many genes,including those involved in lipid metabolism.In this report,we showed that GCNF specifically interacts with PPARδ promoter.Overexpression of GCNF in African green monkey SV40 transformed kidney fibroblast COS7 cells and mouse embryo fibroblast NIH 3T3 cells represses the activity of PPARδ promoter.The mutation of GCNF response element in PPARδ promoter relieves the repression in NIH 3T3 cells and mouse testis.Moreover,we showed that GCNF in nuclear extracts of mouse testis is able to bind to PPARδ promoter directly.We also found that GCNF and PPARδ mRNA were expressed with different patterns in mouse testis by in situ hybridization.These results suggested that GCNF might be a negative regulator of PPARδ gene expression through its direct interaction with PPARδ promoter in mouse testis.

  15. The oncoprotein HBXIP upregulates PDGFB via activating transcription factor Sp1 to promote the proliferation of breast cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yingyi; Zhao, Yu; Li, Leilei; Shen, Yu; Cai, Xiaoli [Department of Biochemistry, College of Life Sciences, Nankai University, Tianjin 300071 (China); Zhang, Xiaodong, E-mail: zhangxd@nankai.edu.cn [Department of Cancer Research, Institute for Molecular Biology, College of Life Sciences, Nankai University, Tianjin 300071 (China); Ye, Lihong, E-mail: yelihong@nankai.edu.cn [Department of Biochemistry, College of Life Sciences, Nankai University, Tianjin 300071 (China)

    2013-05-03

    Highlights: •HBXIP is able to upregulate the expression of PDGFB in breast cancer cells. •HBXIP serves as a coactivator of activating transcription factor Sp1. •HBXIP stimulates the PDGFB promoter via activating transcription factor Sp1. •HBXIP promotes the proliferation of breast cancer cell via upregulating PDGFB. -- Abstract: We have reported that the oncoprotein hepatitis B virus X-interacting protein (HBXIP) acts as a novel transcriptional coactivator to promote proliferation and migration of breast cancer cells. Previously, we showed that HBXIP was able to activate nuclear factor-κB (NF-κB) in breast cancer cells. As an oncogene, the platelet-derived growth factor beta polypeptide (PDGFB) plays crucial roles in carcinogenesis. In the present study, we found that both HBXIP and PDGFB were highly expressed in breast cancer cell lines. Interestingly, HBXIP was able to increase transcriptional activity of NF-κB through PDGFB, suggesting that HBXIP is associated with PDGFB in the cells. Moreover, HBXIP was able to upregulate PDGFB at the levels of mRNA, protein and promoter in the cells. Then, we identified that HBXIP stimulated the promoter of PDGFB through activating transcription factor Sp1. In function, HBXIP enhanced the proliferation of breast cancer cells through PDGFB in vitro. Thus, we conclude that HBXIP upregulates PDGFB via activating transcription factor Sp1 to promote proliferation of breast cancer cells.

  16. Zinc promotes proliferation and activation of myogenic cells via the PI3K/Akt and ERK signaling cascade

    Energy Technology Data Exchange (ETDEWEB)

    Ohashi, Kazuya, E-mail: asuno10k@yahoo.co.jp [Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo (Japan); Nagata, Yosuke, E-mail: cynagata@mail.ecc.u-tokyo.ac.jp [Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo (Japan); Wada, Eiji, E-mail: gacchu1@yahoo.co.jp [Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo (Japan); Zammit, Peter S., E-mail: peter.zammit@kcl.ac.uk [Randall Division of Cell and Molecular Biophysics, King' s College London, London SE1 1UL (United Kingdom); Shiozuka, Masataka, E-mail: cmuscle@mail.ecc.u-tokyo.ac.jp [Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo (Japan); Matsuda, Ryoichi, E-mail: cmatsuda@mail.ecc.u-tokyo.ac.jp [Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo (Japan)

    2015-05-01

    Skeletal muscle stem cells named muscle satellite cells are normally quiescent but are activated in response to various stimuli, such as injury and overload. Activated satellite cells enter the cell cycle and proliferate to produce a large number of myogenic progenitor cells, and these cells then differentiate and fuse to form myofibers. Zinc is one of the essential elements in the human body, and has multiple roles, including cell growth and DNA synthesis. However, the role of zinc in myogenic cells is not well understood, and is the focus of this study. We first examined the effects of zinc on differentiation of murine C2C12 myoblasts and found that zinc promoted proliferation, with an increased number of cells incorporating EdU, but inhibited differentiation with reduced myogenin expression and myotube formation. Furthermore, we used the C2C12 reserve cell model of myogenic quiescence to investigate the role of zinc on activation of myogenic cells. The number of reserve cells incorporating BrdU was increased by zinc in a dose dependent manner, with the number dramatically further increased using a combination of zinc and insulin. Akt and extracellular signal-regulated kinase (ERK) are downstream of insulin signaling, and both were phosphorylated after zinc treatment. The zinc/insulin combination-induced activation involved the phosphoinositide 3-kinase (PI3K)/Akt and ERK cascade. We conclude that zinc promotes activation and proliferation of myogenic cells, and this activation requires phosphorylation of PI3K/Akt and ERK as part of the signaling cascade. - Highlights: • Zinc has roles for promoting proliferation and inhibition differentiation of C2C12. • Zinc promotes activation of reserve cells. • Insulin and zinc synergize activation of reserve cells. • PI3K/Akt and ERK cascade affect zinc/insulin-mediated activation of reserve cells.

  17. Zinc promotes proliferation and activation of myogenic cells via the PI3K/Akt and ERK signaling cascade

    International Nuclear Information System (INIS)

    Skeletal muscle stem cells named muscle satellite cells are normally quiescent but are activated in response to various stimuli, such as injury and overload. Activated satellite cells enter the cell cycle and proliferate to produce a large number of myogenic progenitor cells, and these cells then differentiate and fuse to form myofibers. Zinc is one of the essential elements in the human body, and has multiple roles, including cell growth and DNA synthesis. However, the role of zinc in myogenic cells is not well understood, and is the focus of this study. We first examined the effects of zinc on differentiation of murine C2C12 myoblasts and found that zinc promoted proliferation, with an increased number of cells incorporating EdU, but inhibited differentiation with reduced myogenin expression and myotube formation. Furthermore, we used the C2C12 reserve cell model of myogenic quiescence to investigate the role of zinc on activation of myogenic cells. The number of reserve cells incorporating BrdU was increased by zinc in a dose dependent manner, with the number dramatically further increased using a combination of zinc and insulin. Akt and extracellular signal-regulated kinase (ERK) are downstream of insulin signaling, and both were phosphorylated after zinc treatment. The zinc/insulin combination-induced activation involved the phosphoinositide 3-kinase (PI3K)/Akt and ERK cascade. We conclude that zinc promotes activation and proliferation of myogenic cells, and this activation requires phosphorylation of PI3K/Akt and ERK as part of the signaling cascade. - Highlights: • Zinc has roles for promoting proliferation and inhibition differentiation of C2C12. • Zinc promotes activation of reserve cells. • Insulin and zinc synergize activation of reserve cells. • PI3K/Akt and ERK cascade affect zinc/insulin-mediated activation of reserve cells

  18. Effects of herbal compound 861 on human hepatic stellate cell proliferation and activation

    Institute of Scientific and Technical Information of China (English)

    Lin Wang; Jian Wang; Bao-En Wang; Pei-Gen Xiao; Yan-Jiang Qiao; Xue-Hai Tan

    2004-01-01

    AIM: To investigate the effects of herbal compound 861(Cpd 861) on cell proliferation in human hepatic stellate cells (LX-2) and human hepatocellular liver carcinoma cells(HepG2), and expression of α-smooth muscle actin (α-SMA)in LX-2 cells.METHODS: LX-2 and HepG2 cells were incubated withvarious concentrations of Cpd 861 (0.1-0.003 mg/mL)for 1,2, 3, 5 and 7 d. Cell proliferation was analyzed by 3-(4, 5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) assay. Effects of Cpd861on the expression of α-SMA mRNA in LX-2 cells were measured by real-time quantitative PCR method using SYBR Green I technology.RESULTS: Cpd 861, at 0.1 mg/mL, significantly inhibited LX-2 cell proliferation (15% decrease relative to control,P<0.05) after 3 d of incubation. The inhibitory effects seemed to increase with the treatment time (25% decrease after 5 d of incubation and 35% decrease after 7 d of incubation,P<0.01). However, Cpd 861 did not affect HepG2 cell proliferation at the same concentration used for LX-2 cells.The expression levels of α-SMA mRNA decreased significantly when LX-2 cells were exposed to Cpd 861 for 48 h (59%decrease relative to control, P<0.05) or 72 h (60% decrease relative to control, P<0.01).CONCLUSION: Cpd 861 can significantly inhibit LX-2 cell proliferation in a dose-dependant manner, and reduce the expression levels of α-SMA mRNA in LX-2 cells. Since hepatic cell proliferation and high level of α-SMA are associated with liver fibrosis, the results suggest that Cpd 861 may be useful in the treatment of this disease.

  19. EPO-independent functional EPO receptor in breast cancer enhances estrogen receptor activity and promotes cell proliferation

    Energy Technology Data Exchange (ETDEWEB)

    Reinbothe, Susann; Larsson, Anna-Maria; Vaapil, Marica; Wigerup, Caroline [Department of Laboratory Medicine, Translational Cancer Research, Medicon Village, Lund University, SE-223 81 Lund (Sweden); CREATE Health, Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv (Israel); Sun, Jianmin [Department of Laboratory Medicine, Translational Cancer Research, Medicon Village, Lund University, SE-223 81 Lund (Sweden); Jögi, Annika [Department of Laboratory Medicine, Translational Cancer Research, Medicon Village, Lund University, SE-223 81 Lund (Sweden); CREATE Health, Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv (Israel); Neumann, Drorit [Department of Cell and Developmental Biology, Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv (Israel); Rönnstrand, Lars [Department of Laboratory Medicine, Translational Cancer Research, Medicon Village, Lund University, SE-223 81 Lund (Sweden); Påhlman, Sven, E-mail: sven.pahlman@med.lu.se [Department of Laboratory Medicine, Translational Cancer Research, Medicon Village, Lund University, SE-223 81 Lund (Sweden); CREATE Health, Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv (Israel)

    2014-02-28

    Highlights: • New anti-human EPOR antibody confirms full-length EPOR expression in breast cancer cells. • Proliferation of breast cancer cells is not affected by rhEPO treatment in vitro. • EPOR knockdown impairs proliferation of ERa positive breast cancer cells. • EPOR knockdown reduces AKT phosphorylation and ERa activity. - Abstract: The main function of Erythropoietin (EPO) and its receptor (EPOR) is the stimulation of erythropoiesis. Recombinant human EPO (rhEPO) is therefore used to treat anemia in cancer patients. However, clinical trials have indicated that rhEPO treatment might promote tumor progression and has a negative effect on patient survival. In addition, EPOR expression has been detected in several cancer forms. Using a newly produced anti-EPOR antibody that reliably detects the full-length isoform of the EPOR we show that breast cancer tissue and cells express the EPOR protein. rhEPO stimulation of cultured EPOR expressing breast cancer cells did not result in increased proliferation, overt activation of EPOR (receptor phosphorylation) or a consistent activation of canonical EPOR signaling pathway mediators such as JAK2, STAT3, STAT5, or AKT. However, EPOR knockdown experiments suggested functional EPO receptors in estrogen receptor positive (ERα{sup +}) breast cancer cells, as reduced EPOR expression resulted in decreased proliferation. This effect on proliferation was not seen in ERα negative cells. EPOR knockdown decreased ERα activity further supports a mechanism by which EPOR affects proliferation via ERα-mediated mechanisms. We show that EPOR protein is expressed in breast cancer cells, where it appears to promote proliferation by an EPO-independent mechanism in ERα expressing breast cancer cells.

  20. EPO-independent functional EPO receptor in breast cancer enhances estrogen receptor activity and promotes cell proliferation

    International Nuclear Information System (INIS)

    Highlights: • New anti-human EPOR antibody confirms full-length EPOR expression in breast cancer cells. • Proliferation of breast cancer cells is not affected by rhEPO treatment in vitro. • EPOR knockdown impairs proliferation of ERa positive breast cancer cells. • EPOR knockdown reduces AKT phosphorylation and ERa activity. - Abstract: The main function of Erythropoietin (EPO) and its receptor (EPOR) is the stimulation of erythropoiesis. Recombinant human EPO (rhEPO) is therefore used to treat anemia in cancer patients. However, clinical trials have indicated that rhEPO treatment might promote tumor progression and has a negative effect on patient survival. In addition, EPOR expression has been detected in several cancer forms. Using a newly produced anti-EPOR antibody that reliably detects the full-length isoform of the EPOR we show that breast cancer tissue and cells express the EPOR protein. rhEPO stimulation of cultured EPOR expressing breast cancer cells did not result in increased proliferation, overt activation of EPOR (receptor phosphorylation) or a consistent activation of canonical EPOR signaling pathway mediators such as JAK2, STAT3, STAT5, or AKT. However, EPOR knockdown experiments suggested functional EPO receptors in estrogen receptor positive (ERα+) breast cancer cells, as reduced EPOR expression resulted in decreased proliferation. This effect on proliferation was not seen in ERα negative cells. EPOR knockdown decreased ERα activity further supports a mechanism by which EPOR affects proliferation via ERα-mediated mechanisms. We show that EPOR protein is expressed in breast cancer cells, where it appears to promote proliferation by an EPO-independent mechanism in ERα expressing breast cancer cells

  1. Dysfunction of nucleus accumbens-1 activates cellular senescence and inhibits tumor cell proliferation and oncogenesis.

    Science.gov (United States)

    Zhang, Yi; Cheng, Yan; Ren, Xingcong; Hori, Tsukasa; Huber-Keener, Kathryn J; Zhang, Li; Yap, Kai Lee; Liu, David; Shantz, Lisa; Qin, Zheng-Hong; Zhang, Suping; Wang, Jianrong; Wang, Hong-Gang; Shih, Ie-Ming; Yang, Jin-Ming

    2012-08-15

    Nucleus accumbens-1 (NAC1), a nuclear factor belonging to the BTB/POZ gene family, has emerging roles in cancer. We report here that NAC1 acts as a negative regulator of cellular senescence in transformed and nontransformed cells, and dysfunction of NAC1 induces senescence and inhibits its oncogenic potential. We show that NAC1 deficiency markedly activates senescence and inhibits proliferation in tumor cells treated with sublethal doses of γ-irradiation. In mouse embryonic fibroblasts from NAC1 knockout mice, following infection with a Ras virus, NAC1-/- cells undergo significantly more senescence and are either nontransformed or less transformed in vitro and less tumorigenic in vivo when compared with NAC1+/+ cells. Furthermore, we show that the NAC1-caused senescence blunting is mediated by ΔNp63, which exerts its effect on senescence through p21, and that NAC1 activates transcription of ΔNp63 under stressful conditions. Our results not only reveal a previously unrecognized function of NAC1, the molecular pathway involved and its impact on pathogenesis of tumor initiation and development, but also identify a novel senescence regulator that may be exploited as a potential target for cancer prevention and treatment.

  2. Cell proliferation and migration are modulated by Cdk-1-phosphorylated endothelial-monocyte activating polypeptide II.

    Directory of Open Access Journals (Sweden)

    Margaret A Schwarz

    Full Text Available BACKGROUND: Endothelial-Monocyte Activating Polypeptide (EMAP II is a secreted protein with well-established anti-angiogenic activities. Intracellular EMAP II expression is increased during fetal development at epithelial/mesenchymal boundaries and in pathophysiologic fibroproliferative cells of bronchopulmonary dysplasia, emphysema, and scar fibroblast tissue following myocardial ischemia. Precise function and regulation of intracellular EMAP II, however, has not been explored to date. METHODOLOGY/PRINCIPAL FINDINGS: Here we show that high intracellular EMAP II suppresses cellular proliferation by slowing progression through the G2M cell cycle transition in epithelium and fibroblast. Furthermore, EMAP II binds to and is phosphorylated by Cdk1, and exhibits nuclear/cytoplasmic partitioning, with only nuclear EMAP II being phosphorylated. We observed that extracellular secreted EMAP II induces endothelial cell apoptosis, where as excess intracellular EMAP II facilitates epithelial and fibroblast cells migration. CONCLUSIONS/SIGNIFICANCE: Our findings suggest that EMAP II has specific intracellular effects, and that this intracellular function appears to antagonize its extracellular anti-angiogenic effects during fetal development and pulmonary disease progression.

  3. 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....

  4. Activation and proliferation of lymphocytes and other mammalian cells in microgravity

    Science.gov (United States)

    Cogoli, A.; Cogoli-Greuter, M.

    1997-01-01

    The experimental findings reviewed in this chapter support the following conclusions: Proliferation. Human T-lymphocytes, associated with monocytes as accessory cells, show dramatic changes in the centrifuge, in the clinostat and in space. In free-floating cells the mitogenic response is depressed by 90% in microgravity, whereas in cells attached to a substratum activation is enhanced by 100% compared to 1-G ground and inflight controls. The duration of phase G1 of the mitotic cycle of HeLa cells is reduced in hypergravity, resulting in an increased proliferation rate. Other systems like Friend cells and WI38 human embryonic lung cells do not show significant changes. Genetic expression and signal transduction. T-lymphocytes and monocytes show important changes in the expression of cytokines like interleukin-1, interleukin-2, interferon-gamma and tumor necrosis factor. The data from space experiments in Spacelab, Space Shuttle mid-deck, and Biokosmos have helped to clarify certain aspects of the mechanism of T-cell activation. Epidermoid A431 cells show changes in the genetic expression of the proto-oncogenes c-fos and c-jun in the clinostat and in sounding rockets. Membrane function, in particular the binding of ligates as first messengers of a signal, is not changed in most of the cell systems in microgravity. Morphology and Mortility. Free cells, lymphocytes in particular, are able to move and form aggregates in microgravity, indicating that cell-cell contacts and cell communications do take place in microgravity. Dramatic morphological and ultrastructural changes are not detected in cells cultured in microgravity. Important experiments with single mammalian cells, including immune cells, were carried out recently in three Spacelab flights, (SL-J, D-2, and IML-2 in 1992, 1993, and 1994, respectively). The results of the D-2 mission have been published in ref. 75; those of the IML-2 mission in ref. 76. Finally, many cell biology experiments in space have suffered

  5. Chemerin Stimulates Vascular Smooth Muscle Cell Proliferation and Carotid Neointimal Hyperplasia by Activating Mitogen-Activated Protein Kinase Signaling

    Science.gov (United States)

    Xiong, Wei; Luo, Yu; Wu, Lin; Liu, Feng; Liu, Huadong; Li, Jianghua; Liao, Bihong; Dong, Shaohong

    2016-01-01

    Vascular neointimal hyperplasia and remodeling arising from local inflammation are characteristic pathogeneses of proliferative cardiovascular diseases, such as atherosclerosis and post angioplasty restenosis. The molecular mechanisms behind these pathological processes have not been fully determined. The adipokine chemerin is associated with obesity, metabolism, and control of inflammation. Recently, chemerin has gained increased attention as it was found to play a critical role in the development of cardiovascular diseases. In this study, we investigated the effects of chemerin on the regulation of vascular smooth muscle cells and carotid neointimal formation after angioplasty. We found that circulating chemerin levels increased after carotid balloon injury, and that knockdown of chemerin significantly inhibited the proliferative aspects of vascular smooth muscle cells induced by platelet-derived growth factor-BB and pro-inflammatory chemokines in vitro as well as prohibited carotid neointimal hyperplasia and pro-inflammatory chemokines in vivo after angioplasty. Additionally, inhibition of chemerin down-regulated the expression of several proteins, including phosphorylated p38 mitogen-activated protein kinase, phosphorylated extracellular signal regulated kinase 1/2, nuclear factor-kappa B p65, and proliferation cell nuclear antigen. The novel finding of this study is that chemerin stimulated vascular smooth muscle cells proliferation and carotid intimal hyperplasia through activation of the mitogen-activated protein kinase signaling pathway, which may lead to vascular inflammation and remodeling, and is relevant to proliferative cardiovascular diseases. PMID:27792753

  6. Functional role of HLA class I cell-surface molecules in human T-lymphocyte activation and proliferation.

    OpenAIRE

    Taylor, D S; Nowell, P C; Kornbluth, J

    1986-01-01

    This investigation addressed the role of major histocompatibility complex-encoded class I molecules in the activation and proliferation of human lymphocytes. We studied the effect of antibodies specific for HLA-A and HLA-B locus gene products on mitogen-stimulated peripheral blood mononuclear cell (PBMC) subpopulations. Three individually derived, well-characterized anti-HLA class I monoclonal antibodies were demonstrated to inhibit the proliferation of human PBMC stimulated by either OKT3 or...

  7. Glioma Cell Proliferation Controlled by ERK Activity-Dependent Surface Expression of PDGFRA

    OpenAIRE

    Dongfeng Chen; Duo Zuo; Cheng Luan; Min Liu; Manli Na; Liang Ran; Yingyu Sun; Annette Persson; Elisabet Englund; Leif G Salford; Erik Renström; Xiaolong Fan; Enming Zhang

    2014-01-01

    Increased PDGFRA signaling is an essential pathogenic factor in many subtypes of gliomas. In this context the cell surface expression of PDGFRA is an important determinant of ligand sensing in the glioma microenvironment. However, the regulation of spatial distribution of PDGFRA in glioma cells remains poorly characterized. Here, we report that cell surface PDGFRA expression in gliomas is negatively regulated by an ERK-dependent mechanism, resulting in reduced proliferation of glioma cells. G...

  8. Berbamine inhibits proliferation and induces apoptosis of KU812 cells by increasing Smad3 activity

    Institute of Scientific and Technical Information of China (English)

    Yun LIANG; Xi QIU; Rong-zhen XU; Xiao-ying ZHAO

    2011-01-01

    Objective:The cytotoxic effect of berbamine on chronic myeloid leukemia (CML) cell line KU812 was evaluated,and the mechanisms of its action were explored.Methods:The effect of berbamine on the KU812 cell growth was determined by methyl thiazolyl tetrazolium (MTT) assay.Flow cytometry was used to profile cell cycle alteration upon berbamine treatment.Reverse transcription polymerase chain reaction (RT-PCR) was carried out to determine the transcripts of transforming growth factor-β (TGF-β) receptors (TβRs),Smad3,c-Myc,cyclin D1,p21Cip1 (p21),and p27Kip1 (p27).Changes in the protein levels of total Smad3,phosphorylated Smad3,the downstream targets of Smad3,and specific apoptosis-related factors were evaluated by Western blotting.Results:Berbamine inhibited KU812 cell proliferation in a dose-and time-dependent manner,and the half maximal inhibitory concentration (IC50) values for treatments of 24,48,and 72 h were 5.83,3.43,and 0.75 μg/ml,respectively.Berbamine induced G1 arrest as well as apoptosis in KU812 cells.Transcriptions of Smad3 and p21 were up-regulated,while those of TβRI,TβRII,c-Myc,cyclin D1 and p27 were not changed significantly.The protein levels of both total Smad3 and phosphorylated Smad3 were both up-regulated after berbamine treatment,together with decreased c-Myc and cyclin D1 and increased p21.Meanwhile,the levels of the anti-apoptotic proteins,such as Bcl-2 and Bcl-xL,were decreased,whereas pro-apoptotic Bax was increased.Conclusions:Berbamine suppresses KU812 cell proliferation through induction of cell cycle arrest in G1 and apoptosis.It activates Smad3 without additional stimulation of TGF-β,and alters the levels of the Smad3 downstream targets,including c-Myc,cyclin D1 and p21.Our findings suggest that berbamine is a promising drug in the treatment of advanced stage patients with CML.

  9. Stimulation of murine stem cell proliferation by circulating activities produced during the recovery of a radiation-induced hemopoietic injury

    International Nuclear Information System (INIS)

    The proliferative activity of CFU-S, low in normal steady state, increases after treatment with different aggressors, i.e. radiation. This stimulation has been attributed in part to a local regulation system of stem cell proliferation, and at least in part to a humoral regulatory system. In the present work it has been investigated the role that circulating activities have in the CFU- S stimulation, by means of in vitro and in vivo incubation assays with diffusion chambers. The results show that bone marrow of mice irradiated with 5 Gy produces in vitro diffusible activities capable of stimulating the CFU-S proliferation. As well with this same dose circulating activities are also produced in vivo. In addition we have observed that these activities are only released during the periods of active hemopoietic regeneration that follow irradiation with moderate doses (1.5 and 5 Gy). In another set of experiments we saw that the stimulating activities are also detected in serum of mice irradiated with 5 Gy. These serum activities modify the proliferative state of very primitive precursors (12 d CFU-S). When the serum activities are added to long term bone marrow cultures the CFU-S) are also stimulated to proliferate. Finally, we observed that the radiation-induced serum activities stimulate the proliferation of bone marrow CFU-S when injected into normal mice, suggesting that such activities are involved in the regulation of CFU-S proliferation. (Author)

  10. Interleukin 3 stimulates proliferation and triggers endothelial-leukocyte adhesion molecule 1 gene activation of human endothelial cells.

    Science.gov (United States)

    Brizzi, M F; Garbarino, G; Rossi, P R; Pagliardi, G L; Arduino, C; Avanzi, G C; Pegoraro, L

    1993-06-01

    Proliferation and functional activation of endothelial cells within a tissue site of inflammation are regulated by humoral factors released by cells, such as T lymphocytes and monocytes, infiltrating the perivascular space. In the present study we investigated the effects of interleukin 3 (IL-3), an activated T lymphocyte-derived cytokine, on cultured human umbilical vein endothelial cells (HUVEC). Proliferative activity, evaluated both by estimation of the fraction of cells in the S phase and by direct cell count demonstrated that IL-3, at the dose of 25 ng/ml, enhances more than threefold both DNA synthesis and cell proliferation above baseline control conditions. Binding studies with radioiodinated ligand demonstrated that HUVEC constitutively express a smaller number of IL-3 binding sites (approximately 99 binding sites per cell, with an apparent Kd of 149 pM). Accordingly, molecular analysis showed the presence of transcripts for both alpha and beta subunits of the IL-3 receptor. Functional activation of endothelial cells was evaluated by the expression of the endothelial-leukocyte adhesion molecule 1 (ELAM-1) transcript and by leukocyte adhesion. The ELAM-1 gene transcript was clearly detectable 4 h after IL-3 addition and started to decrease after 12 h. Moreover, IL-3-induced ELAM-1 transcription was followed by enhanced adhesion of neutrophils and CD4+ T cells to HUVEC. The findings that IL-3 can stimulate both proliferation and functional activation of endothelial cells suggest that this cytokine can be involved in sustaining the process of chronic inflammation.

  11. Effect of Cigarette Smoke Extract on the Proliferation of Human Airway Epithelial Cells and Expression and Activation of FAK

    Institute of Scientific and Technical Information of China (English)

    XU Li; ZHANG Zhenxiang; XU Yongjian

    2005-01-01

    Summary: The effect of cigarette smoke extract (CSE) on the proliferation of human airway epithelial cells and the possible mechanism was studied. After airway epithelial cells were treated with different concentrations of CSE for 24 h, the cell proliferation was measured by MTT and the distribution of different cell cycles by flow cytometry. The FAK expression level was detected by Western blot and the degree of tyrosine phosphorylation by immunoprecipitation. The results showed that CSE could inhibit the proliferation of human airway epithelial cells, arrest the epithelial cells in G1 phase of cell cycle, dramatically decrease the number of epithelial cells in S and G2 phases; Meanwhile CSE could decrease the expression level of FAK and the degree of its tyrosine phosphorylation. The above effects of CSE were concentration-dependent. The expression of FAK and the degree of its phosphorylation was positively correlated to the increased number of epithelial cells in G1 phase, and negatively to the number of epithelial cells in S and G2 phases. It was concluded that the mechanism by which CSE could inhibit the proliferation of human epithelial cells was contributed to the increased expression and activation of FAK.

  12. Negative regulators of cell proliferation

    Science.gov (United States)

    Johnson, T. C.; Spooner, B. S. (Principal Investigator)

    1994-01-01

    Cell proliferation is governed by the influence of both mitogens and inhibitors. Although cell contact has long been thought to play a fundamental role in cell cycling regulation, and negative regulators have long been suspected to exist, their isolation and purification has been complicated by a variety of technical difficulties. Nevertheless, over recent years an ever-expanding list of putative negative regulators have emerged. In many cases, their biological inhibitory activities are consistent with density-dependent growth inhibition. Most likely their interactions with mitogenic agents, at an intracellular level, are responsible for either mitotic arrest or continued cell cycling. A review of naturally occurring cell growth inhibitors is presented with an emphasis on those factors shown to be residents of the cell surface membrane. Particular attention is focused on a cell surface sialoglycopeptide, isolated from intact bovine cerebral cortex cells, which has been shown to inhibit the proliferation of an unusually wide range of target cells. The glycopeptide arrest cells obtained from diverse species, both fibroblasts and epithelial cells, and a broad variety of transformed cells. Signal transduction events and a limited spectrum of cells that are refractory to the sialoglycopeptide have provided insight into the molecular events mediated by this cell surface inhibitor.

  13. Proliferation, migration and apoptosis activities of endothelial progenitor cells in acute coronary syndrome

    Institute of Scientific and Technical Information of China (English)

    ZHANG Li-jie; LIU Wen-xian; CHEN Yun-dai; SONG Xian-tao; JIN Ze-ning; L(U) Shu-zheng

    2010-01-01

    Background There are numerous articles on the endothelial progenitor cells (EPCs) in different disease conditions.However, the functional properties of EPCs in acute coronary syndrome (ACS) are still uncertain. Here we aimed to study the number and functions of EPCs in ACS patients.Methods Patients were enrolled with admitted ACS (n=25) and another 25 gender-, age-, atherosclerotic risk factors-matched stable coronary artery disease (CAD) controls. EPCs were defined as CD34+/CD133+/VEGFR-2+ and quantified by flow cytometry. Moreover, functional properties of EPCs including colony-forming unit (CFU), proliferation,migration as well as apoptosis were evaluated and compared between the two groups. Plasma matrix metalloproteinase-9 (MMP-9) was detected in all patients as well.Results The two groups had similar medication and clinical characteristics on admission. The EPCs in ACS patients were more than 2.6 times that in stable CAD subjects (15.6±2.7 vs. 6.0±0.8/100 000 events, P <0.01). CFU was not statistically different between the two groups (10.8±2.9 vs. 8.2±1.8, number/well, P >0.05). Furthermore, EPCs isolated from ACS patients were significantly impaired in their proliferation (0.498±0.035 vs. 0.895±0.067, OD value, P <0.01) and migration capacity (20.5±3.4 vs. 30.7±4.3, number/well, P <0.01) compared with controls. Moreover, the apoptosis cell in cultured EPCs was drastically increased in ACS group ((18.3 ±2.1 )% vs. (7.8±0.4)%, P <0.01 ).Conclusions Patients with ACS exhibited apparently increased circulating EPCs as well as cultured apoptosis percentage together with a remarkable impairment of proliferation and migration activities compared with stable CAD subjects.

  14. Scorpion venom component III inhibits cell proliferation by modulating NF-κB activation in human leukemia cells

    Science.gov (United States)

    SONG, XIANGFENG; ZHANG, GUOJUN; SUN, AIPING; GUO, JIQIANG; TIAN, ZHONGWEI; WANG, HUI; LIU, YUFENG

    2012-01-01

    Scorpion venom contains various groups of compounds that exhibit anticancer activity against a variety of malignancies through a poorly understood mechanism. While the aberrant activation of nuclear factor κB (NF-κB) has been linked with hematopoietic malignancies, we hypothesized that scorpion venom mediates its effects by modulating the NF-κB signaling pathway. In the present study, we examined the effects of scorpion venom component III (SVCIII) on the human leukemia cell lines THP-1 and Jurkat and focused on the NF-κB signaling pathway. Our results showed that SVCIII inhibited cell proliferation, caused cell cycle arrest at G1 phase and inhibited the expression of cell cycle regulatory protein cyclin D1 in a dose-dependent manner in THP-1 and Jurkat cells. SVCIII also suppressed the constitutive NF-κB activation through inhibition of the phosphorylation and degradation of IκBα. NF-κB luciferase reporter activity was also inhibited by SVCIII. Our data suggest that SVCIII, a natural compound, may exert its antiproliferative effects by inhibiting the activation of NF-κB and, thus, has potential use in the treatment of hematopoietic malignancies, alone or in combination with other agents. PMID:23060939

  15. Bile acids induce hepatic stellate cell proliferation via activation of the epidermal growth factor receptor

    NARCIS (Netherlands)

    Svegliati-Baroni, G; Ridolfi, F; Hannivoort, R; Saccomanno, S; Homan, M; De Minicis, S; Jansen, PLM; Candelaresi, C; Benedetti, A; Moshage, H

    2005-01-01

    Background B Aims: Hepatic stellate cell (HSC) proliferation is a key event in the development of liver fibrosis. In many liver diseases, HSCs are exposed to inflammatory cytokines, reactive oxygen species, and bile acids. Although inflammatory cytokines and reactive oxygen species are known to prom

  16. Ribonucleotide reductase activity is coupled to DNA synthesis via proliferating cell nuclear antigen.

    Science.gov (United States)

    Salguero, Israel; Guarino, Estrella; Shepherd, Marianne E A; Deegan, Tom D; Havens, Courtney G; MacNeill, Stuart A; Walter, Johannes C; Kearsey, Stephen E

    2012-04-24

    Synthesis of deoxynucleoside triphosphates (dNTPs) is required for both DNA replication and DNA repair and is catalyzed by ribonucleotide reductases (RNR), which convert ribonucleotides to their deoxy forms [1, 2]. Maintaining the correct levels of dNTPs for DNA synthesis is important for minimizing the mutation rate [3-7], and this is achieved by tight regulation of RNR [2, 8, 9]. In fission yeast, RNR is regulated in part by a small protein inhibitor, Spd1, which is degraded in S phase and after DNA damage to allow upregulation of dNTP supply [10-12]. Spd1 degradation is mediated by the activity of the CRL4(Cdt2) ubiquitin ligase complex [5, 13, 14]. This has been reported to be dependent on modulation of Cdt2 levels, which are cell cycle regulated, peaking in S phase, and which also increase after DNA damage in a checkpoint-dependent manner [7, 13]. We show here that Cdt2 level fluctuations are not sufficient to regulate Spd1 proteolysis and that the key step in this event is the interaction of Spd1 with the polymerase processivity factor proliferating cell nuclear antigen (PCNA), complexed onto DNA. This mechanism thus provides a direct link between DNA synthesis and RNR regulation. PMID:22464192

  17. Piper betle shows antioxidant activities, inhibits MCF-7 cell proliferation and increases activities of catalase and superoxide dismutase

    Directory of Open Access Journals (Sweden)

    Abrahim Noor

    2012-11-01

    Full Text Available Abstract Background Breast cancer is the most common form of cancer and the focus on finding chemotherapeutic agents have recently shifted to natural products. Piper betle is a medicinal plant with various biological activities. However, not much data is available on the anti-cancer effects of P. betle on breast cancer. Due to the current interest in the potential effects of antioxidants from natural products in breast cancer treatment, we investigated the antioxidant activities of the leaves of P. betle and its inhibitory effect on the proliferation of the breast cancer cell line, MCF-7. Methods The leaves of P. betle were extracted with solvents of varying polarities (water, methanol, ethyl acetate and hexane and their phenolic and flavonoid content were determined using colorimetric assays. Phenolic composition was characterized using HPLC. Antioxidant activities were measured using FRAP, DPPH, superoxide anion, nitric oxide and hyroxyl radical scavenging assays. Biological activities of the extracts were analysed using MTT assay and antioxidant enzyme (catalase, superoxide dismutase, glutathione peroxidase assays in MCF-7 cells. Results Overall, the ethyl acetate extract showed the highest ferric reducing activity and radical scavenging activities against DPPH, superoxide anion and nitric oxide radicals. This extract also contained the highest phenolic content implying the potential contribution of phenolics towards the antioxidant activities. HPLC analyses revealed the presence of catechin, morin and quercetin in the leaves. The ethyl acetate extract also showed the highest inhibitory effect against the proliferation of MCF-7 cells (IC50=65 μg/ml. Treatment of MCF-7 cells with the plant extract increased activities of catalase and superoxide dismutase. Conclusions Ethyl acetate is the optimal solvent for the extraction of compounds with antioxidant and anti-proliferative activities. The increased activities of catalase and superoxide

  18. ChREBP Mediates Glucose Repression of Peroxisome Proliferator-activated Receptor {alpha} Expression in Pancreatic {beta}-Cells

    DEFF Research Database (Denmark)

    Boergesen, Michael; Poulsen, Lars la Cour; Schmidt, Søren Fisker;

    2011-01-01

    Chronic exposure to elevated levels of glucose and fatty acids leads to dysfunction of pancreatic β-cells by mechanisms that are only partly understood. The transcription factor peroxisome proliferator-activated receptor α (PPARα) is an important regulator of genes involved in fatty acid metaboli...... of glucose repression of PPARα gene expression in pancreatic β-cells, suggesting that ChREBP may be important for glucose suppression of the fatty acid oxidation capacity of β-cells....

  19. Zizyphus lotus L. (Desf. modulates antioxidant activity and human T-cell proliferation

    Directory of Open Access Journals (Sweden)

    Belarbi Meriem

    2010-09-01

    Full Text Available Abstract Background Zizyphus lotus L. (Desf. also known as Jujube, is a deciduous shrub which belongs to Rhamnaceae family. This plant is used in Algerian traditional medicine for its anti-diabetic, sedative, analgesic, anti-inflammatory and hypoglycaemic activities. In the present study, we determined the concentrations of different vitamins (vitamin A, C and E and fatty acids in root, stem, leaves, fruit pulp and seed of Zizyphus lotus L. (Desf. and assessed the effects of their aqueous extracts on antioxidant status and human T-cell proliferation. Methods Aqueous filtrates from different parts, i.e, root, leaf, stem, fruit pulp and seed, of Zizyphus lotus L. (Desf. were prepared. Vitamin C levels were determined by precipitating with 10% trichloroacetic acid and vitamin A and E were assessed by HPLC. Lipid composition of these extracts was determined by gas-liquid chromatography. Anti-oxidant capacity was evaluated by using anti-radical resistance kit [Kit Radicaux Libres (KRL@; Kirial International SA, Couternon, France]. T-cell blastogenesis was assessed by the incorporation of 3H-thymidine. IL-2 gene expression was evaluated by RT-qPCR. Results Our results show that fruit pulp contained higher vitamin A and C contents than other parts of the plant. Furthermore, the fruit pulp was the richest source of linoleic acid (18:2n-6, a precursor of n-6 fatty acids. Fruit seeds possessed higher vitamin C levels than leaves, roots and stem. The leaves were the richest source of vitamin E and linolenic acid (18:3n-3, a precursor of n-3 fatty acids. The antioxidant capacity of the different extracts, measured by KRL@ test, was as follows: pulp Zizyphus lotus L. (Desf. exerted immunosuppressive effects. Conclusion Seed extracts exerted the most potent immunosuppressive effects on T cell proliferation and IL-2 mRNA expression. The results of the present study are discussed in the light of their use to modulate the immune-mediated diseases.

  20. The threonine protease activity of testes-specific protease 50 (TSP50 is essential for its function in cell proliferation.

    Directory of Open Access Journals (Sweden)

    Yu-Yin Li

    Full Text Available BACKGROUND: Testes-specific protease 50 (TSP50, a newly discovered threonine enzyme, has similar amino acid sequences and enzymatic structures to those of many serine proteases. It may be an oncogene. TSP50 is up-regulated in breast cancer epithelial cells, and ectopic expression of TSP50 in TSP50-deficient Chinese hamster ovary (CHO cells has been found to promote cell proliferation. However, the mechanisms by which TSP50 exerts its growth-promoting effects are not yet fully understood. METHODOLOGY/PRINCIPAL FINDINGS: To delineate whether the threonine protease activity of TSP50 is essential to its function in cell proliferation, we constructed and characterized a mutant TSP50, called TSP50 T310A, which was identified as a protease-dead mutant of TSP50. By a series of proliferation analyses, colony formation assays and apoptosis analyses, we showed that T310A mutation significantly depresses TSP50-induced cell proliferation in vitro. Next, the CHO stable cell line expressing either wild-type or T310A mutant TSP50 was injected subcutaneously into nude mice. We found that the T310A mutation could abolish the tumorigenicity of TSP50 in vivo. A mechanism investigation revealed that the T310A mutation prevented interaction between TSP50 and the NF-κBIκBα complex, which is necessary for TSP50 to perform its function in cell proliferation. CONCLUSION: Our data highlight the importance of threonine 310, the most critical protease catalytic site in TSP50, to TSP50-induced cell proliferation and tumor formation.

  1. Glioma cell proliferation controlled by ERK activity-dependent surface expression of PDGFRA.

    Science.gov (United States)

    Chen, Dongfeng; Zuo, Duo; Luan, Cheng; Liu, Min; Na, Manli; Ran, Liang; Sun, Yingyu; Persson, Annette; Englund, Elisabet; Salford, Leif G; Renström, Erik; Fan, Xiaolong; Zhang, Enming

    2014-01-01

    Increased PDGFRA signaling is an essential pathogenic factor in many subtypes of gliomas. In this context the cell surface expression of PDGFRA is an important determinant of ligand sensing in the glioma microenvironment. However, the regulation of spatial distribution of PDGFRA in glioma cells remains poorly characterized. Here, we report that cell surface PDGFRA expression in gliomas is negatively regulated by an ERK-dependent mechanism, resulting in reduced proliferation of glioma cells. Glioma tumor tissues and their corresponding cell lines were isolated from 14 patients and analyzed by single-cell imaging and flow cytometry. In both cell lines and their corresponding tumor samples, glioma cell proliferation correlated with the extent of surface expression of PDGFRA. High levels of surface PDGFRA also correlated to high tubulin expression in glioma tumor tissue in vivo. In glioma cell lines, surface PDGFRA declined following treatment with inhibitors of tubulin, actin and dynamin. Screening of a panel of small molecule compounds identified the MEK inhibitor U0126 as a potent inhibitor of surface PDGFRA expression. Importantly, U0126 inhibited surface expression in a reversible, dose- and time-dependent manner, without affecting general PDGFRA expression. Treatment with U0126 resulted in reduced co-localization between PDGFRA and intracellular trafficking molecules e.g. clathrin, RAB11 and early endosomal antigen-1, in parallel with enhanced co-localization between PDGFRA and the Golgi cisternae maker, Giantin, suggesting a deviation of PDGFRA from the endosomal trafficking and recycling compartment, to the Golgi network. Furthermore, U0126 treatment in glioma cells induced an initial inhibition of ERK1/2 phosphorylation, followed by up-regulated ERK1/2 phosphorylation concomitant with diminished surface expression of PDGFRA. Finally, down-regulation of surface PDGFRA expression by U0126 is concordant with reduced glioma cell proliferation. These findings

  2. Glioma cell proliferation controlled by ERK activity-dependent surface expression of PDGFRA.

    Directory of Open Access Journals (Sweden)

    Dongfeng Chen

    Full Text Available Increased PDGFRA signaling is an essential pathogenic factor in many subtypes of gliomas. In this context the cell surface expression of PDGFRA is an important determinant of ligand sensing in the glioma microenvironment. However, the regulation of spatial distribution of PDGFRA in glioma cells remains poorly characterized. Here, we report that cell surface PDGFRA expression in gliomas is negatively regulated by an ERK-dependent mechanism, resulting in reduced proliferation of glioma cells. Glioma tumor tissues and their corresponding cell lines were isolated from 14 patients and analyzed by single-cell imaging and flow cytometry. In both cell lines and their corresponding tumor samples, glioma cell proliferation correlated with the extent of surface expression of PDGFRA. High levels of surface PDGFRA also correlated to high tubulin expression in glioma tumor tissue in vivo. In glioma cell lines, surface PDGFRA declined following treatment with inhibitors of tubulin, actin and dynamin. Screening of a panel of small molecule compounds identified the MEK inhibitor U0126 as a potent inhibitor of surface PDGFRA expression. Importantly, U0126 inhibited surface expression in a reversible, dose- and time-dependent manner, without affecting general PDGFRA expression. Treatment with U0126 resulted in reduced co-localization between PDGFRA and intracellular trafficking molecules e.g. clathrin, RAB11 and early endosomal antigen-1, in parallel with enhanced co-localization between PDGFRA and the Golgi cisternae maker, Giantin, suggesting a deviation of PDGFRA from the endosomal trafficking and recycling compartment, to the Golgi network. Furthermore, U0126 treatment in glioma cells induced an initial inhibition of ERK1/2 phosphorylation, followed by up-regulated ERK1/2 phosphorylation concomitant with diminished surface expression of PDGFRA. Finally, down-regulation of surface PDGFRA expression by U0126 is concordant with reduced glioma cell proliferation

  3. Designed modulation of sex steroid signaling inhibits telomerase activity and proliferation of human prostate cancer cells

    International Nuclear Information System (INIS)

    The predominant estrogen-receptor (ER)-β signaling in normal prostate is countered by increased ER-α signaling in prostate cancer (CaP), which in association with androgen-receptor (AR) signaling results in pathogenesis of the disease. However CaP treatments mostly target AR signaling which is initially effective but eventually leads to androgen resistance, hence simultaneous targeting of ERs has been proposed. A novel series of molecules were designed with multiple sex-steroid receptor modulating capabilities by coalescing the pharmacophores of known anti-CaP molecules that act via modulation of ER(α/β) and/or AR, viz. 3,3′diindolylmethane (DIM), mifepristone, toremifene, tamoxifen and raloxifene. N,N-diethyl-4-((2-(4-methoxyphenyl)-1H-indol-3-yl)methyl) aniline (DIMA) was identified as the most promising structure of this new series. DIMA increased annexin-V labelling, cell-cycle arrest and caspase-3 activity, and decreased expression of AR and prostate specific antigen in LNCaP cells, in vitro. Concurrently, DIMA increased ER-β, p21 and p27 protein levels in LNCaP cells and exhibited ∼ 5 times more selective binding for ER-β than ER-α, in comparison to raloxifene. DIMA exhibited a dose-dependent ER-β agonism and ER-α antagonism in classical gene reporter assay and decreased hTERT (catalytic subunit of telomerase) transcript levels in LNCaP at 3.0 μM (P < 0.05). DIMA also dose-dependently decreased telomerase enzyme activity in prostate cancer cells. It is thus concluded that DIMA acts as a multi-steroid receptor modulator and effectively inhibits proliferation of prostate cancer cells through ER-β mediated telomerase inhibition, by countering actions of ER-α and AR. Its unique molecular design can serve as a lead structure for generation of potent agents against endocrine malignancies like the CaP

  4. Designed modulation of sex steroid signaling inhibits telomerase activity and proliferation of human prostate cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Verma, Vikas; Sharma, Vikas; Singh, Vishal [Division of Endocrinology, CSIR-Central Drug Research Institute, Lucknow 226 031 (India); Sharma, Siddharth; Bishnoi, Ajay Kumar [Division of Medicinal and Process Chemistry, CSIR-Central Drug Research Institute, Lucknow 226 031 (India); Chandra, Vishal; Maikhuri, J.P.; Dwivedi, Anila [Division of Endocrinology, CSIR-Central Drug Research Institute, Lucknow 226 031 (India); Kumar, Atul [Division of Medicinal and Process Chemistry, CSIR-Central Drug Research Institute, Lucknow 226 031 (India); Gupta, Gopal, E-mail: g_gupta@cdri.res.in [Division of Endocrinology, CSIR-Central Drug Research Institute, Lucknow 226 031 (India)

    2014-10-15

    The predominant estrogen-receptor (ER)-β signaling in normal prostate is countered by increased ER-α signaling in prostate cancer (CaP), which in association with androgen-receptor (AR) signaling results in pathogenesis of the disease. However CaP treatments mostly target AR signaling which is initially effective but eventually leads to androgen resistance, hence simultaneous targeting of ERs has been proposed. A novel series of molecules were designed with multiple sex-steroid receptor modulating capabilities by coalescing the pharmacophores of known anti-CaP molecules that act via modulation of ER(α/β) and/or AR, viz. 3,3′diindolylmethane (DIM), mifepristone, toremifene, tamoxifen and raloxifene. N,N-diethyl-4-((2-(4-methoxyphenyl)-1H-indol-3-yl)methyl) aniline (DIMA) was identified as the most promising structure of this new series. DIMA increased annexin-V labelling, cell-cycle arrest and caspase-3 activity, and decreased expression of AR and prostate specific antigen in LNCaP cells, in vitro. Concurrently, DIMA increased ER-β, p21 and p27 protein levels in LNCaP cells and exhibited ∼ 5 times more selective binding for ER-β than ER-α, in comparison to raloxifene. DIMA exhibited a dose-dependent ER-β agonism and ER-α antagonism in classical gene reporter assay and decreased hTERT (catalytic subunit of telomerase) transcript levels in LNCaP at 3.0 μM (P < 0.05). DIMA also dose-dependently decreased telomerase enzyme activity in prostate cancer cells. It is thus concluded that DIMA acts as a multi-steroid receptor modulator and effectively inhibits proliferation of prostate cancer cells through ER-β mediated telomerase inhibition, by countering actions of ER-α and AR. Its unique molecular design can serve as a lead structure for generation of potent agents against endocrine malignancies like the CaP.

  5. MiR-27a Promotes Hepatocellular Carcinoma Cell Proliferation Through Suppression of its Target Gene Peroxisome Proliferator-activated Receptor γ

    Institute of Scientific and Technical Information of China (English)

    Shuo Li; Jing Li; Bing-Yuan Fei; Dan Shao; Yue Pan; Zhan-Hao Mo; Bao-Zhen Sun

    2015-01-01

    Background:MicroRNAs (miRNAs) function as essential posttranscriptional modulators ofgene expression,and are involved in a wide range of physiologic and pathologic states,including cancer.Numerous miRNAs are deregulated in hepatocellular carcinoma (HCC).This study aimed to investigate the role of miR-27a in the development of HCC.Methods:The expression of MiR-27a was measured by quantitative real-time polymerase chain reaction (qRT-PCR).3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide was used to examine changes in the viability of HepG2,Bel-7402,Bel-7404 hepatoma cell lines associated with up-regulation or down-regulation of miR-27a.A dual-luciferase activity assay was used to verify a target gene of miR-27a.Immunohistochemistry,qRT-PCR,Western blotting analysis,and cell cycle and apoptosis flow cytometric assays were used to elucidate the mechanism by which miR-27a modulates liver cancer cell proliferation.Results:The expression of miR-27a was significantly increased in HCC tissues and HepG2,Bel-7402,Bel-7404 hepatoma cell lines (P < 0.05).We also found that the down-regulation of miR-27a in HepG2 cells dramatically inhibited proliferation,blocked the G1 to S cell cycle transition and induced apoptosis (P < 0.05).In addition,miR-27a directly targeted the 3'-untranslated region of peroxisome proliferator-activated receptor γ (PPAR-γ),and ectopic miR-27a expression suppressed PPAR-γ expression on the mRNA and protein levels.The rosiglitazone-induced overexpression of PPAR-γ attenuated the effect of miR-27a in HCC cells.Conclusions:Our findings suggested that miRNA-27a promoted HCC cell proliferation by regulating PPAR-γ expression.MiR-27a may provide a potential therapeutic strategy for HCC treatment.

  6. MicroRNA-200a mediates nasopharyngeal carcinoma cell proliferation through the activation of nuclear factor-κB.

    Science.gov (United States)

    Shi, Zhuliang; Hu, Zhiqiang; Chen, Delu; Huang, Jie; Fan, Jie; Zhou, Subo; Wang, Xin; Hu, Jiandao; Huang, Fei

    2016-02-01

    In nasopharyngeal carcinoma (NPC), the nuclear factor-κB (NF-κB) signaling pathway is highly active. The constitutive activation of NF-κB prompts malignant cell proliferation, and microRNAs are considered an important mediator in regulating the NF-κB signaling pathway. The current study investigated the effect of microRNA-200a (miR-200a) on NF-κB activation. Reverse transcription-quantitative polymerase chain reaction was used to quantify the relative level of miR-200a in NPC tissue samples and CNE2 cells. An MTT assay was used to investigate the effect of miR-200a on cell proliferation. To investigate the activation of NF-κB, western blotting was used to measure the protein levels of NF-κB and its downstream targets. To identify the target genes of miR-200a, a luciferase reporter assay was used. The current study demonstrated that miR-200a was upregulated in NPC tissue samples and cell lines. Overexpression of miR-200a resulted in the proliferation of CNE2 cells. Western blot analysis indicated that the protein levels of p65 increased when CNE2 cells were transfected with miR-200a mimics. Additionally, the downstream targets of miR-200a were upregulated, including vascular cell adhesion molecule, intercellular adhesion molecule and monocyte chemoattractant protein-1. The luciferase assay indicated that IκBα was the target gene of miR-200a. In conclusion, miR-200a was demonstrated to enhance NPC cell proliferation by activating the NF-κB signaling pathway.

  7. Control of cell proliferation by Myc

    DEFF Research Database (Denmark)

    Bouchard, C; Staller, P; Eilers, M

    1998-01-01

    Myc proteins are key regulators of mammalian cell proliferation. They are transcription factors that activate genes as part of a heterodimeric complex with the protein Max. This review summarizes recent progress in understanding how Myc stimulates cell proliferation and how this might contribute...

  8. Shock Waves Increase T-cell Proliferation or IL-2 Expression by Activating p38 MAP Kinase

    Institute of Scientific and Technical Information of China (English)

    Tie-Cheng YU; Yi LIU; Yan TAN; Yanfang JIANG; Xueqing ZHENG; Xinxiang XU

    2004-01-01

    Shock waves were elicited by transient pressure disturbances, which could be used to treat musculoskeletal disorders. In present studies, we i. nvestigated whether the low-density shock waves (LDSWs), which are able to damage plasma membrane without impairing the vimentin or other organelles, might augment T-cell proliferation as well as IL-2 expression, and if mitogen activated protein kinase p38 (p38 MAPK)might be an underlying mechanism through which the LDSWs enhanced T-cell function. We found that the LDSWs increased activation of p38 MAPK in Jurkat T cells. The LDSWs alone didn't result in the T-cell proliferation and IL-2 expression. However, in combination with other stimuli, LDSWs could augment the T-cell proliferation and IL-2 expression. Inhibition of p38 MAPK using SB203580 reduced the stimulatory effects of the LDSWs, which indicated that the LDSWs enhanced IL-2 expression through a mechanism that involved p38 MAPK activation. We concluded that the p38 MAPK activation played a key role in the regulation of T cell function by the LDSWs.

  9. MicroRNA-19a mediates gastric carcinoma cell proliferation through the activation of nuclear factor-κB.

    Science.gov (United States)

    Yang, Fan; Wang, Hongjian; Jiang, Zhenyu; Hu, Anxiang; Chu, Lisha; Sun, Yiling; Han, Junqing

    2015-10-01

    In gastric carcinoma, the nuclear factor‑κB (NF‑κB) signaling pathway is highly active, and the constitutive activation of NF‑κB prompts malignant cell proliferation. MicroRNAs are considered to be important mediators in the regulation of the NF‑κB signaling pathway. The present study predominantly focussed on the effects of microRNA (miR)‑19a on NF‑κB activation. Reverse transcription‑quantitative polymerase chain reaction was used to quantify the relative levels of miR‑19a in gastric carcinoma cells. MTT assays were used to determine the effect of miR‑19a on cellular proliferation. To detect the activation of NF‑κB, western blotting was performed to measure the protein levels of NF‑κB and the products of its downstream target genes. To define the target genes, luciferase reporter assays were used. miR‑19a was found to be markedly upregulated in gastric carcinoma cells. The overexpression of miR‑19a resulted in proliferation and enhanced migratory capabilities of the MGC‑803 gastric carcinoma cell line. The results of the western blot analysis demonstrated that the protein levels of p65 increased when the MGC‑803 cells were transfected with miR‑19a mimics. In addition, the downstream target genes of miR‑19a, including intercellular adhesion molecule, vascular cell adhesion molecule and monocyte chemoattractant protein‑1, were upregulated. The results of the luciferase assay indicated that IκB‑α was the target gene of miR‑19a. Therefore, the results of the present study suggested that miR‑19a enhances malignant gastric cell proliferation by constitutively activating the NF‑κB signaling pathway.

  10. EGFR is dispensable for c-Met-mediated proliferation and survival activities in mouse adult liver oval cells.

    Science.gov (United States)

    Martínez-Palacián, A; del Castillo, G; Herrera, B; Fernández, M; Roncero, C; Fabregat, I; Sánchez, A

    2012-02-01

    Liver progenitor cells rise as potential critical players in hepatic regeneration but also carcinogenesis. It is therefore mandatory to define the signals controlling their activation and expansion. Recently, by using a novel in vitro model of oval cell lines expressing a mutant tyrosine kinase-inactive form of c-Met we demonstrated that autocrine c-Met signalling plays an essential role in promoting oval cell survival. Here, we investigated the significance of the epidermal growth factor receptor (EGFR) signalling in oval cell proliferation and survival, as well as a potential functional crosstalk between the c-Met and the EGFR pathways. We found an autocrine activation of the EGFR-triggered pathway in Met(flx/flx) and Met(-/-) oval cells as judged by constitutive expression of the EGFR ligands, transforming growth factor-alpha (TGF-α) and heparin-binding EGF like growth factor (HB-EGF), and activation of EGFR. On the other hand, treatment with AG1478, a specific inhibitor of EGFR, effectively blocked endogenous and EGF-induced proliferation, while increased serum withdrawal and transforming growth factor-beta (TGF-β)-induced apoptosis. These results suggest that constitutively activated EGFR might promote oval cell proliferation and survival. We found that hepatocyte growth factor (HGF) does not transactivate EGFR nor EGF transactivates c-Met. Furthermore, treatment with AG1478 or EGFR gene silencing did not interfere with HGF-mediated activation of target signals, such as protein kinase B (AKT/PKB), and extracellular signal-regulated kinases 1/2 (ERK 1/2), nor did it have any effect on HGF-induced proliferative and antiapoptotic activities in Met(flx/flx) cells, showing that HGF does not require EGFR activation to mediate such responses. EGF induced proliferation and survival equally in Met(flx/flx) and Met(-/-) oval cells, proving that EGFR signalling does not depend on c-Met tyrosine kinase activity. Together, our results provide strong evidence that in

  11. Impaired Peroxisome Proliferator-activated Receptor-γ Contributes to Phenotypic Modulation of Vascular Smooth Muscle Cells during Hypertension*

    Science.gov (United States)

    Zhang, Lili; Xie, Peng; Wang, Jingzhou; Yang, Qingwu; Fang, Chuanqin; Zhou, Shuang; Li, Jingcheng

    2010-01-01

    The phenotypic modulation of vascular smooth muscle cells (VSMCs) plays a pivotal role in hypertension-induced vascular changes including vascular remodeling. The precise mechanisms underlying VSMC phenotypic modulation remain elusive. Here we test the role of peroxisome proliferator-activated receptor (PPAR)-γ in the VSMC phenotypic modulation during hypertension. Both spontaneously hypertensive rat (SHR) aortas and SHR-derived VSMCs exhibited reduced PPAR-γ expression and excessive VSMC phenotypic modulation identified by reduced contractile proteins, α-smooth muscle actin (α-SMA) and smooth muscle 22α (SM22α), and enhanced proliferation and migration. PPAR-γ overexpression rescued the expression of α-SMA and SM22α, and inhibited the proliferation and migration in SHR-derived VSMCs. In contrast, PPAR-γ silencing exerted the opposite effect. Activating PPAR-γ using rosiglitazone in vivo up-regulated aortic α-SMA and SM22α expression and attenuated aortic remodeling in SHRs. Increased activation of phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT) signaling was observed in SHR-derived VSMCs. PI3K inhibitor LY294002 rescued the impaired expression of contractile proteins, and inhibited proliferation and migration in VSMCs from SHRs, whereas constitutively active PI3K mutant had the opposite effect. Overexpression or silencing of PPAR-γ inhibited or excited PI3K/Akt activity, respectively. LY294002 counteracted the PPAR-γ silencing induced proliferation and migration in SHR-derived VSMCs, whereas active PI3K mutant had the opposite effect. In contrast, reduced proliferation and migration by PPAR-γ overexpression were reversed by the active PI3K mutant, and further inhibited by LY294002. We conclude that PPAR-γ inhibits VSMC phenotypic modulation through inhibiting PI3K/Akt signaling. Impaired PPAR-γ expression is responsible for VSMC phenotypic modulation during hypertension. These findings highlight an attractive therapeutic target for

  12. Erbin loss promotes cancer cell proliferation through feedback activation of Akt-Skp2-p27 signaling

    International Nuclear Information System (INIS)

    Erbin localizes at the basolateral membrane to regulate cell junctions and polarity in epithelial cells. Dysregulation of Erbin has been implicated in tumorigenesis, and yet it is still unclear if and how disrupted Erbin regulates the biological behavior of cancer cells. We report here that depletion of Erbin leads to cancer cell excessive proliferation in vitro and in vivo. Erbin deficiency accelerates S-phase entry by down-regulating CDK inhibitors p21 and p27 via two independent mechanisms. Mechanistically, Erbin loss promotes p27 degradation by enhancing E3 ligase Skp2 activity though augmenting Akt signaling. Interestingly, we also show that Erbin is an unstable protein when the Akt-Skp2 signaling is aberrantly activated, which can be specifically destructed by SCF-Skp2 ligase. Erbin loss facilitates cell proliferation and migration in Skp2-dependent manner. Thus, our finding illustrates a novel negative feedback loop between Erbin and Akt-Skp2 signaling. It suggests disrupted Erbin links polarity loss, hyperproliferation and tumorigenesis. - Highlights: • Erbin loss leads to cancer cell excessive proliferation in vitro and in vivo. • Erbin loss accelerates cell cycle though down-regulating p21 and p27 expression. • Erbin is a novel negative modulator of Akt1-Skp2-p27 signaling pathway. • Our study suggests that Erbin loss contributes to Skp2 oncogenic function

  13. Erbin loss promotes cancer cell proliferation through feedback activation of Akt-Skp2-p27 signaling

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Hao [Department of Pathophysiology, Institute of Basic Medical Sciences, Beijing 100850 (China); Laboratory of Cellular and Molecular Immunology, Medical School of Henan University, Kaifeng 475004 (China); Song, Yuhua [The Affiliated Hospital of Medical College, Qingdao University, Qingdao (China); Wu, Yan; Guo, Ning [Department of Pathophysiology, Institute of Basic Medical Sciences, Beijing 100850 (China); Ma, Yuanfang [Laboratory of Cellular and Molecular Immunology, Medical School of Henan University, Kaifeng 475004 (China); Qian, Lu, E-mail: mayf@henu.edu.cn [Department of Pathophysiology, Institute of Basic Medical Sciences, Beijing 100850 (China)

    2015-07-31

    Erbin localizes at the basolateral membrane to regulate cell junctions and polarity in epithelial cells. Dysregulation of Erbin has been implicated in tumorigenesis, and yet it is still unclear if and how disrupted Erbin regulates the biological behavior of cancer cells. We report here that depletion of Erbin leads to cancer cell excessive proliferation in vitro and in vivo. Erbin deficiency accelerates S-phase entry by down-regulating CDK inhibitors p21 and p27 via two independent mechanisms. Mechanistically, Erbin loss promotes p27 degradation by enhancing E3 ligase Skp2 activity though augmenting Akt signaling. Interestingly, we also show that Erbin is an unstable protein when the Akt-Skp2 signaling is aberrantly activated, which can be specifically destructed by SCF-Skp2 ligase. Erbin loss facilitates cell proliferation and migration in Skp2-dependent manner. Thus, our finding illustrates a novel negative feedback loop between Erbin and Akt-Skp2 signaling. It suggests disrupted Erbin links polarity loss, hyperproliferation and tumorigenesis. - Highlights: • Erbin loss leads to cancer cell excessive proliferation in vitro and in vivo. • Erbin loss accelerates cell cycle though down-regulating p21 and p27 expression. • Erbin is a novel negative modulator of Akt1-Skp2-p27 signaling pathway. • Our study suggests that Erbin loss contributes to Skp2 oncogenic function.

  14. Berry anthocyanins reduce proliferation of human colorectal carcinoma cells by inducing caspase-3 activation and p21 upregulation.

    Science.gov (United States)

    Anwar, Sirajudheen; Fratantonio, Deborah; Ferrari, Daniela; Saija, Antonella; Cimino, Francesco; Speciale, Antonio

    2016-08-01

    Colorectal cancer is the fourth most common type of cancer worldwide, and adenocarcinoma cells that form the majority of colorectal tumors are markedly resistant to antineoplastic agents. Epidemiological studies have demonstrated that consumption of fruits and vegetables that are rich in polyphenols, is linked to reduced risk of colorectal cancer. In the present study, the effect of a standardized anthocyanin (ACN)‑rich extract on proliferation, apoptosis and cell cycle in the Caco-2 human colorectal cancer cell line was evaluated by trypan blue and clonogenic assays and western blot analysis of cleaved caspase‑3 and p21Waf/Cif1. The results of the current study demonstrated that the ACN extract markedly decreased Caco‑2 cell proliferation, induced apoptosis by activating caspase‑3 cleavage, and upregulated cyclin‑dependent kinase inhibitor 1 (p21Waf/Cif1) expression in a dose dependent manner. Furthermore, ACN extract was able to produce a dose‑dependent increase of intracellular reactive oxygen species (ROS) in Caco‑2 cells, together with a light increase of the cell total antioxidant status. In conclusion, the present study demonstrated that a standardized berry anthocyanin rich extract inhibited proliferation of Caco‑2 cells by promoting ROS accumulation, inducing caspase‑3 activation, and upregulating the expression of p21Waf/Cif1. PMID:27314273

  15. Estradiol and GPER Activation Differentially Affect Cell Proliferation but Not GPER Expression in the Hippocampus of Adult Female Rats.

    Directory of Open Access Journals (Sweden)

    Paula Duarte-Guterman

    Full Text Available Estradiol increases cell proliferation in the dentate gyrus of the female rodent but it is not known whether the G protein-coupled estrogen receptor (GPER, a membrane receptor, is involved in this process, nor whether there are regional differences in estradiol's effects on cell proliferation. Thus, we investigated whether estradiol exerts its effects on cell proliferation in the dorsal and ventral dentate gyrus through GPER, using the GPER agonist, G1, and antagonist, G15. Ovariectomized adult female rats received a single injection of either: 17β-estradiol (10 μg, G1 (0.1, 5, 10 μg, G15 (40 μg, G15 and estradiol, or vehicle (oil, DMSO, or oil+DMSO. After 30 min, animals received an injection of bromodeoxyuridine (BrdU and were perfused 24 h later. Acute treatment with estradiol increased, while the GPER agonist G1 (5 μg decreased, the number of BrdU+ cells in the dentate gyrus relative to controls. The GPER antagonist, G15 increased the number of BrdU+ cells relative to control in the dorsal region and decreased the number of BrdU+ cells in the ventral region. However, G15 treatment in conjunction with estradiol partially eliminated the estradiol-induced increase in cell proliferation in the dorsal dentate gyrus. Furthermore, G1 decreased the expression of GPER in the dentate gyrus but not the CA1 and CA3 regions of the hippocampus. In summary, we found that activation of GPER decreased cell proliferation and GPER expression in the dentate gyrus of young female rats, presenting a potential and novel estrogen-independent role for this receptor in the adult hippocampus.

  16. Tumor cells with KRAS or BRAF mutations or ERK5/MAPK7 amplification are not addicted to ERK5 activity for cell proliferation.

    Science.gov (United States)

    Lochhead, Pamela A; Clark, Jonathan; Wang, Lan-Zhen; Gilmour, Lesley; Squires, Matthew; Gilley, Rebecca; Foxton, Caroline; Newell, David R; Wedge, Stephen R; Cook, Simon J

    2016-01-01

    ERK5, encoded by MAPK7, has been proposed to play a role in cell proliferation, thus attracting interest as a cancer therapeutic target. While oncogenic RAS or BRAF cause sustained activation of the MEK1/2-ERK1/2 pathway, ERK5 is directly activated by MEK5. It has been proposed that RAS and RAF proteins can also promote ERK5 activation. Here we investigated the interplay between RAS-RAF-MEK-ERK and ERK5 signaling and studied the role of ERK5 in tumor cell proliferation in 2 disease-relevant cell models. We demonstrate that although an inducible form of CRAF (CRAF:ER*) can activate ERK5 in fibroblasts, the response is delayed and reflects feed-forward signaling. Additionally, oncogenic KRAS and BRAF do not activate ERK5 in epithelial cells. Although KRAS and BRAF do not couple directly to MEK5-ERK5, ERK5 signaling might still be permissive for proliferation. However, neither the selective MEK5 inhibitor BIX02189 or ERK5 siRNA inhibited proliferation of colorectal cancer cells harbouring KRAS(G12C/G13D) or BRAF(V600E). Furthermore, there was no additive or synergistic effect observed when BIX02189 was combined with the MEK1/2 inhibitor Selumetinib (AZD6244), suggesting that ERK5 was neither required for proliferation nor a driver of innate resistance to MEK1/2 inhibitors. Finally, even cancer cells with MAPK7 amplification were resistant to BIX02189 and ERK5 siRNA, showing that ERK5 amplification does not confer addiction to ERK5 for cell proliferation. Thus ERK5 signaling is unlikely to play a role in tumor cell proliferation downstream of KRAS or BRAF or in tumor cells with ERK5 amplification. These results have important implications for the role of ERK5 as an anti-cancer drug target.

  17. Tumor cells with KRAS or BRAF mutations or ERK5/MAPK7 amplification are not addicted to ERK5 activity for cell proliferation

    Science.gov (United States)

    Lochhead, Pamela A.; Clark, Jonathan; Wang, Lan-Zhen; Gilmour, Lesley; Squires, Matthew; Gilley, Rebecca; Foxton, Caroline; Newell, David R.; Wedge, Stephen R.; Cook, Simon J.

    2016-01-01

    Abstract ERK5, encoded by MAPK7, has been proposed to play a role in cell proliferation, thus attracting interest as a cancer therapeutic target. While oncogenic RAS or BRAF cause sustained activation of the MEK1/2-ERK1/2 pathway, ERK5 is directly activated by MEK5. It has been proposed that RAS and RAF proteins can also promote ERK5 activation. Here we investigated the interplay between RAS-RAF-MEK-ERK and ERK5 signaling and studied the role of ERK5 in tumor cell proliferation in 2 disease-relevant cell models. We demonstrate that although an inducible form of CRAF (CRAF:ER*) can activate ERK5 in fibroblasts, the response is delayed and reflects feed-forward signaling. Additionally, oncogenic KRAS and BRAF do not activate ERK5 in epithelial cells. Although KRAS and BRAF do not couple directly to MEK5-ERK5, ERK5 signaling might still be permissive for proliferation. However, neither the selective MEK5 inhibitor BIX02189 or ERK5 siRNA inhibited proliferation of colorectal cancer cells harbouring KRASG12C/G13D or BRAFV600E. Furthermore, there was no additive or synergistic effect observed when BIX02189 was combined with the MEK1/2 inhibitor Selumetinib (AZD6244), suggesting that ERK5 was neither required for proliferation nor a driver of innate resistance to MEK1/2 inhibitors. Finally, even cancer cells with MAPK7 amplification were resistant to BIX02189 and ERK5 siRNA, showing that ERK5 amplification does not confer addiction to ERK5 for cell proliferation. Thus ERK5 signaling is unlikely to play a role in tumor cell proliferation downstream of KRAS or BRAF or in tumor cells with ERK5 amplification. These results have important implications for the role of ERK5 as an anti-cancer drug target. PMID:26959608

  18. Orphan nuclear receptor TLX activates Wnt/β-catenin signalling to stimulate neural stem cell proliferation and self-renewal

    OpenAIRE

    Qu, Qiuhao; Sun, Guoqiang; Li, Wenwu; Yang, Su; Ye, Peng; Zhao, Chunnian; Yu, Ruth T.; Gage, Fred H; Evans, Ronald M; Shi, Yanhong

    2009-01-01

    The nuclear receptor TLX (also known as NR2E1) is essential for adult neural stem cell self-renewal; however, the molecular mechanisms involved remain elusive. Here we show that TLX activates the canonical Wnt/β-catenin pathway in adult mouse neural stem cells. Furthermore, we demonstrate that Wnt/β-catenin signalling is important in the proliferation and self-renewal of adult neural stem cells in the presence of epidermal growth factor and fibroblast growth factor. Wnt7a and active β-catenin...

  19. Hedgehog signaling activation induces stem cell proliferation and hormone release in the adult pituitary gland

    OpenAIRE

    Joanna Pyczek; Rolf Buslei; David Schult; Annett Hölsken; Michael Buchfelder; Ina Heß; Heidi Hahn; Anja Uhmann

    2016-01-01

    Hedgehog (HH) signaling is known to be essential during the embryonal development of the pituitary gland but the knowledge about its role in the adult pituitary and in associated tumors is sparse. In this report we investigated the effect of excess Hh signaling activation in murine pituitary explants and analyzed the HH signaling status of human adenopituitary lobes and a large cohort of pituitary adenomas. Our data show that excess Hh signaling led to increased proliferation of Sox2+ and Sox...

  20. ADAM17 promotes proliferation of collecting duct kidney epithelial cells through ERK activation and increased glycolysis in polycystic kidney disease.

    Science.gov (United States)

    Beck Gooz, Monika; Maldonado, Eduardo N; Dang, Yujing; Amria, May Y; Higashiyama, Shigeki; Abboud, Hanna E; Lemasters, John J; Bell, P Darwin

    2014-09-01

    Polycystic kidney disease (PKD) is a common genetic disorder leading to cyst formation in the kidneys and other organs that ultimately results in kidney failure and death. Currently, there is no therapy for slowing down or stopping the progression of PKD. In this study, we identified the disintegrin metalloenzyme 17 (ADAM17) as a key regulator of cell proliferation in kidney tissues of conditional knockout Ift88(-/-) mice and collecting duct epithelial cells from Ift88°(rpk) mice, animal models of autosomal recessive polycystic kidney disease (ARPKD). Using Western blotting, an enzyme activity assay, and a growth factor-shedding assay in the presence or absence of the specific ADAM17 inhibitor TMI-005, we show that increased expression and activation of ADAM17 in the cystic kidney and in collecting duct epithelial cells originating from the Ift88°(rpk) mice (designated as PKD cells) lead to constitutive shedding of several growth factors, including heparin-binding EGF-like growth factor (HB-EGF), amphiregulin, and transforming growth factor-α (TGF-α). Increased growth factor shedding induces activation of the EGFR/MAPK/ERK pathway and maintains higher cell proliferation rate in PKD cells compared with control cells. PKD cells also displayed increased lactate formation and extracellular acidification indicative of aerobic glycolysis (Warburg effect), which was blocked by ADAM17 inhibition. We propose that ADAM17 is a key promoter of cellular proliferation in PKD cells by activating the EGFR/ERK axis and a proproliferative glycolytic phenotype. PMID:24899059

  1. Adiponectin and AMP kinase activator stimulate proliferation, differentiation, and mineralization of osteoblastic MC3T3-E1 cells

    Directory of Open Access Journals (Sweden)

    Yamauchi Mika

    2007-11-01

    Full Text Available Abstract Background Adiponectin is a key mediator of the metabolic syndrome that is caused by visceral fat accumulation. Adiponectin and its receptors are known to be expressed in osteoblasts, but their actions with regard to bone metabolism are still unclear. In this study, we investigated the effects of adiponectin on the proliferation, differentiation, and mineralization of osteoblastic MC3T3-E1 cells. Results Adiponectin receptor type 1 (AdipoR1 mRNA was detected in the cells by RT-PCR. The adenosine monophosphate-activated protein kinase (AMP kinase was phosphorylated by both adiponectin and a pharmacological AMP kinase activator, 5-amino-imidazole-4-carboxamide-riboside (AICAR, in the cells. AdipoR1 small interfering RNA (siRNA transfection potently knocked down the receptor mRNA, and the effect of this knockdown persisted for as long as 10 days after the transfection. The transfected cells showed decreased expressions of type I collagen and osteocalcin mRNA, as determined by real-time PCR, and reduced ALP activity and mineralization, as determined by von Kossa and Alizarin red stainings. In contrast, AMP kinase activation by AICAR (0.01–0.5 mM in wild-type MC3T3-E1 cells augmented their proliferation, differentiation, and mineralization. BrdU assay showed that the addition of adiponectin (0.01–1.0 μg/ml also promoted their proliferation. Osterix, but not Runx-2, appeared to be involved in these processes because AdipoR1 siRNA transfection and AICAR treatments suppressed and enhanced osterix mRNA expression, respectively. Conclusion Taken together, this study suggests that adiponectin stimulates the proliferation, differentiation, and mineralization of osteoblasts via the AdipoR1 and AMP kinase signaling pathways in autocrine and/or paracrine fashions.

  2. The Drosophila hindgut lacks constitutively active adult stem cells but proliferates in response to tissue damage

    OpenAIRE

    D.T., Fox; Spradling, A.C.

    2009-01-01

    The adult Drosophila hindgut was recently reported to contain active, tissue-replenishing stem cells, like those of the midgut, but located within an anterior ring so as to comprise a single giant crypt. In contrast to this view, we observed no active stem cells and little cell turnover in adult hindgut tissue based on clonal marking and BrdU incorporation studies. Again contradicting the previous proposal, we showed that the adult hindgut is not generated by anterior stem cells during larval...

  3. NIK is involved in constitutive activation of the alternative NF-κB pathway and proliferation of pancreatic cancer cells

    International Nuclear Information System (INIS)

    Pancreatic cancer has one of the poorest prognoses among human neoplasms. Constitutive activation of NF-κB is frequently observed in pancreatic cancer cells and is involved in their malignancy. However, little is known about the molecular mechanism of this constitutive NF-κB activation. Here, we show that the alternative pathway is constitutively activated and NF-κB-inducing kinase (NIK), a mediator of the alternative pathway, is significantly expressed in pancreatic cancer cells. siRNA-mediated silencing of NIK expression followed by subcellular fractionation revealed that NIK is constitutively involved in the processing of p100 and nuclear transport of p52 and RelB in pancreatic cancer cells. In addition, NIK silencing significantly suppressed proliferation of pancreatic cancer cells. These results clearly indicate that NIK is involved in the constitutive activation of the alternative pathway and controls cell proliferation in pancreatic cancer cells. Therefore, NIK might be a novel target for the treatment of pancreatic cancer.

  4. Cell Proliferation Activity and Prognostic Index in Squamous Cell Lung Carcinoma

    Directory of Open Access Journals (Sweden)

    José Antonio Alvarez-Riesgo

    1998-01-01

    Full Text Available Flow Cytometry (FC has been incorporated into cancer research in relation to its prognostic value together with histological parameters and TNM stages. We have studied by means of FC the cell cycle of 132 samples from male patients with Squamous Cell Lung Carcinoma (SQCLC. All of the patients received curative surgery and the clinical follow-up was 60 months. The clinical and cytometric parameters were evaluated in order to predict the patients’ outcome. The presence of tumoural recurrence and the tumoural stage showed statistical significance associated with survival. The multivariant analysis reveals radiotherapy (p = 0.004 as protective variable and the high S-phase fraction (SPF (p = 0.001 and stage IIIA (p = 0.012 as risk factors. The SPF appears as an independent prognostic factor for overall survival time. We can build a prognostic index representative of different prognostic groups, which allows us to improve the individual monitoring of these patients.

  5. Impaired Peroxisome Proliferator-activated Receptor-γ Contributes to Phenotypic Modulation of Vascular Smooth Muscle Cells during Hypertension*

    OpenAIRE

    Zhang, Lili; Xie, Peng; Wang, Jingzhou; Yang, Qingwu; Fang, Chuanqin; Zhou, Shuang; Li, Jingcheng

    2010-01-01

    The phenotypic modulation of vascular smooth muscle cells (VSMCs) plays a pivotal role in hypertension-induced vascular changes including vascular remodeling. The precise mechanisms underlying VSMC phenotypic modulation remain elusive. Here we test the role of peroxisome proliferator-activated receptor (PPAR)-γ in the VSMC phenotypic modulation during hypertension. Both spontaneously hypertensive rat (SHR) aortas and SHR-derived VSMCs exhibited reduced PPAR-γ expression and excessive VSMC phe...

  6. E-cadherin promotes proliferation of human ovarian cancer cells in vitro via activating MEK/ERK pathway

    Institute of Scientific and Technical Information of China (English)

    Ling-ling DONG; Lian LIU; Chun-hong MA; Ji-sheng LI; Chao DU; Shan XU; Li-hui HAN; Li LI; Xiu-wen WANG

    2012-01-01

    Aim:E-cadherin is unusually highly expressed in most ovarian cancers.This study was designed to investigate the roles of E-cadherin in the carcinogenesis and progression of ovarian cancers.Methods:Human ovarian adenocarcinoma cell line SKOV-3 was examined.E-cadherin gene CDH1 in SKOV-3 cells was knocked down via RNA interference (RNAi),and the resultant variation of biological behavior was observed using CCK-8 and colony formation experiment.E-cadherin-mediated Ca2+-dependent cell-cell adhesion was used to study the mechanisms underlying the effects of E-cadherin on the proliferation and survival of SKOV-3 cells.The expression levels of E-cadherin,extracellular signal-related kinase (ERK),phosphorylated ERK (P-ERK) were measured using Western blot assays.Results:Transfection with CDH1-siRNA for 24-96 h significantly suppressed the growth and proliferation of SKOV-3 cells.E-cadhednmediated calcium-dependent cell-cell adhesion of SKOV-3 cells resulted in a rapid increase of P-ERK,but did not modify the expression of ERK protein.The phosphorylation of ERK in the cells was blocked by pretreatment with the MEK1 specific inhibitor PD98059 (50μmol/L),but not bythe PI3K inhibitor wortmannin (1μmol/L) or PKA inhibitor H89 (10 μmol/L).Conclusion:E-cadherin may function as a tumor proliferation enhancer via activating the MEK/ERK pathway in development of ovarian epithelial cancers.

  7. VEGF induces proliferation of human hair follicle dermal papilla cells through VEGFR-2-mediated activation of ERK

    International Nuclear Information System (INIS)

    Vascular endothelial growth factor (VEGF) is one of the strongest regulators of physiological and pathological angiogenesis. VEGF receptor 2 (VEGFR-2), the primary receptor for VEGF, is thought to mediate major functional effects of VEGF. Previously, we have localized both VEGF and VEGFR-2 in human hair follicles. In this study, we further defined the expression and roles of VEGFR-2 on human hair follicle dermal papilla (DP) cells. The expression of VEGFR-2 on DP cells was examined by reverse transcription-polymerase chain reaction (RT-PCR) and Western blot analysis separately, and localization of VEGFR-2 was defined by immunofluorescence. The effect of VEGF on DP cells was analyzed by MTT assays and specific inhibitors. Finally, the role of VEGF involved in the signaling pathways was investigated by Western blot. RT-PCR and Western blot analysis demonstrated the expression of VEGFR-2 on DP cells. Immunostaining for VEGFR-2 showed strong signal on cultured human DP cells in vitro. Exogenous VEGF165 stimulated proliferation of DP cells in a dose-dependent manner. Furthermore, this stimulation was blocked by a VEGFR-2 neutralizing antibody (MAB3571) and an ERK inhibitor (PD98059). VEGF165-induced phosphorylation of ERK1/2 was abolished by MAB3571 and PD98059, while the phosphorylation of p38, JNK and AKT were not changed by VEGF165. Taken together, VEGFR-2 is expressed on primary human hair follicle DP cells and VEGF induces proliferation of DP cells through VEGFR-2/ERK pathway, but not p38, JNK or AKT signaling. -- Highlights: ► We examine the expression of VEGFR-2 on cultured human dermal papilla (DP) cells. ► VEGF165 stimulated proliferation of human DP cells in a dose-dependent manner. ► This stimulation was through VEGFR-2-mediated activation of ERK.

  8. Differential effect of three mitogen-activated protein kinases on lipoprotein (a)-induced human mesangial cell proliferation

    Institute of Scientific and Technical Information of China (English)

    SONG Hong-mei; WEI Min; XU Ke; LI Xue-wang

    2010-01-01

    Background Mesangial hypercellularity is a critical early histopathological finding in human and experimental glomerular diseases. Hyperlipidemia and the glomerular deposition of lipoproteins are commonly associated with mesangial hypercellularity and play an important pathobiological role in the development of glomerular diseases. The activated cytoplasmic mitogen-activated protein kinase (MAPK), including mainly extracellular-signal regulated protein kinase (ERK), c-Jun amino-terminal kinase (JNK), and p38, has been thought to translocate into the nucleus and activate various transcription factors and protooncogenes associated with cell growth and proliferation. Lipoprotein (a) (Lp(a)) has been shown to stimulate proliferation of mesangial cells, but the events of Lp(a) signaling have not yet been characterized. The purpose of this study was to investigate the signal transduction pathways involved in Lp(a)-induced cell proliferation and provide an evidence for the participation of Lp(a) in intracellular signaling pathways for mesangial cell proliferation.Methods Lp(a) was isolated from a patient who was being treated with low density lipoprotein (LDL)-apheresis by density gradient ultracentrifugation and then chromatography. Human mesangial cells (HMCs) were isolated by the sequential sieving technique and stimulated with Lp(a) in different concentration and time course. The DNA synthesis of the cells was measured by [~3H] thymidine incorporation for detecting the proliferation. The expression of all the three members of MAPK family, including ERK1/ERK2, JNK, and p38, and their phosphorylation were detected by Western blotting. Results Lp(a) could induce a significant dose-dependent proliferation of HMCs. The ~3H-TdR incorporation was 1.64±0.31, 1.69±0.48, 3.59±0.68 (P <0.01), 4.14±0.78 (P <0.01), and 4.05±0.55 (P <0.01) (10~3 cpm) at the Lp(a) concentration of 0, 5, 10, 25, and 50 μg/ml, respectively. Lp(a) induced an increase in ERK1/ERK2 phosphorylation

  9. Telomerase activity: A biomarker of cell proliferation, not malignant transformation

    OpenAIRE

    Belair, Cassandra D.; Yeager, Thomas R.; Lopez, Patricia M.; Reznikoff, Catherine A.

    1997-01-01

    Telomerase activity is readily detected in most cancer biopsies, but not in premalignant lesions or in normal tissue samples with a few exceptions that include germ cells and hemopoietic stem cells. Telomerase activity may, therefore, be a useful biomarker for diagnosis of malignancies and a target for inactivation in chemotherapy or gene therapy. These observations have led to the hypothesis that activation of telomerase may be an important step in tumorigenesis. To test this hypothesis, we ...

  10. Differential effects of polysulfated polysaccharide on experimental encephalomyelitis, proliferation of autoimmune T cells, and inhibition of heparanase activity.

    Science.gov (United States)

    Hershkoviz, R; Mor, F; Miao, H Q; Vlodavsky, I; Lider, O

    1995-10-01

    The extravasation of activated T lymphocytes through blood vessel walls and their migration to inflammatory loci are associated with secretion of extracellular matrix (ECM)-degrading enzymes, such as heparanase, which degrades heparan sulfate (HS) moieties of the ECM. The HS-degrading activity of heparanase was found to be inhibited by HS and heparin. Since induction of experimental autoimmune encephalomyelitis (EAE) requires extravasation and migration of autoimmune T cells, degradation of ECM by heparanase is expected to be involved in induction of the disease. Herein, we examined whether laminarin sulfate, a polysulfated polysaccharide (PSS) isolated from the cell walls of seaweeds and subjected to chemical sulfation, could inhibit ECM degradation by mammalian heparanase, and could prevent EAE. PSS was a more potent inhibitor of heparanase-mediated degradation of ECM than heparin. In-vivo, PSS, injected once a week, inhibited the severity of actively-induced EAE in rats. However, inhibition of EAE was not due to an overall suppression of autoimmune T cells, since PSS enhanced the proliferation of myelin basic protein (MBP)-specific, encephalitogenic T cells. PSS-activated autoimmune T cells, but not MBP-activated cells, failed to induce EAE in recipient rats. Moreover, rats injected with PSS-activated T cells were resistant to induction of EAE by anti-MBP CD4+ T cells. Thus, PSS may have potential clinical applications in the treatment of autoimmune diseases. PMID:8579728

  11. Targeting sphingosine kinase 1 in carcinoma cells decreases proliferation and survival by compromising PKC activity and cytokinesis.

    Directory of Open Access Journals (Sweden)

    Nataliya Kotelevets

    Full Text Available Sphingosine kinases (SK catalyze the phosphorylation of proapoptotic sphingosine to the prosurvival factor sphingosine 1-phosphate (S1P, thereby promoting oncogenic processes. Breast (MDA-MB-231, lung (NCI-H358, and colon (HCT 116 carcinoma cells were transduced with shRNA to downregulate SK-1 expression or treated with a pharmacologic SK-1 inhibitor. The effects of SK-1 targeting were investigated by measuring the level of intracellular sphingosine, the activity of protein kinase C (PKC and cell cycle regulators, and the mitotic index. Functional assays included measurement of cell proliferation, colony formation, apoptosis, and cell cycle analysis. Downregulation of SK-1 or its pharmacologic inhibition increased intracellular sphingosine and decreased PKC activity as shown by reduced phosphorylation of PKC substrates. In MDA-MB-231 cells this effect was most pronounced and reduced cell proliferation and colony formation, which could be mimicked using exogenous sphingosine or the PKC inhibitor RO 31-8220. SK-1 downregulation in MDA-MB-231 cells increased the number of cells with 4N and 8N DNA content, and similar effects were observed upon treatment with sphingosine or inhibitors of SK-1 or PKC. Examination of cell cycle regulators unveiled decreased cdc2 activity and expression of Chk1, which may compromise spindle checkpoint function and cytokinesis. Indeed, SK-1 kd cells entered mitosis but failed to divide, and in the presence of taxol also failed to sustain mitotic arrest, resulting in further increased endoreduplication and apoptosis. Our findings delineate an intriguing link between SK-1, PKC and components of the cell cycle machinery, which underlines the significance of SK-1 as a target for cancer therapy.

  12. Estradiol and GPER Activation Differentially Affect Cell Proliferation but Not GPER Expression in the Hippocampus of Adult Female Rats

    OpenAIRE

    Paula Duarte-Guterman; Lieblich, Stephanie E.; Carmen Chow; Galea, Liisa A. M.

    2015-01-01

    Estradiol increases cell proliferation in the dentate gyrus of the female rodent but it is not known whether the G protein-coupled estrogen receptor (GPER), a membrane receptor, is involved in this process, nor whether there are regional differences in estradiol's effects on cell proliferation. Thus, we investigated whether estradiol exerts its effects on cell proliferation in the dorsal and ventral dentate gyrus through GPER, using the GPER agonist, G1, and antagonist, G15. Ovariectomized ad...

  13. Aryl hydrocarbon receptor nuclear translocator (ARNT) isoforms control lymphoid cancer cell proliferation through differentially regulating tumor suppressor p53 activity.

    Science.gov (United States)

    Gardella, Kacie A; Muro, Israel; Fang, Gloria; Sarkar, Krishnakali; Mendez, Omayra; Wright, Casey W

    2016-03-01

    The aryl hydrocarbon receptor nuclear translocator (ARNT) is involved in xenobiotic and hypoxic responses, and we previously showed that ARNT also regulates nuclear factor-κB (NF-κB) signaling by altering the DNA binding activity of the RelB subunit. However, our initial study of ARNT-mediated RelB modulation was based on simultaneous suppression of the two ARNT isoforms, isoform 1 and 3, and precluded the examination of their individual functions. We find here that while normal lymphocytes harbor equal levels of isoform 1 and 3, lymphoid malignancies exhibit a shift to higher levels of ARNT isoform 1. These elevated levels of ARNT isoform 1 are critical to the proliferation of these cancerous cells, as suppression of isoform 1 in a human multiple myeloma (MM) cell line, and an anaplastic large cell lymphoma (ALCL) cell line, triggered S-phase cell cycle arrest, spontaneous apoptosis, and sensitized cells to doxorubicin treatment. Furthermore, co-suppression of RelB or p53 with ARNT isoform 1 prevented cell cycle arrest and blocked doxorubicin induced apoptosis. Together our findings reveal that certain blood cancers rely on ARNT isoform 1 to potentiate proliferation by antagonizing RelB and p53-dependent cell cycle arrest and apoptosis. Significantly, our results identify ARNT isoform 1 as a potential target for anticancer therapies.

  14. VEGF-A/NRP1 stimulates GIPC1 and Syx complex formation to promote RhoA activation and proliferation in skin cancer cells

    Directory of Open Access Journals (Sweden)

    Ayumi Yoshida

    2015-09-01

    Full Text Available Neuropilin-1 (NRP1 has been identified as a VEGF-A receptor. DJM-1, a human skin cancer cell line, expresses endogenous VEGF-A and NRP1. In the present study, the RNA interference of VEGF-A or NRP1 suppressed DJM-1 cell proliferation. Furthermore, the overexpression of the NRP1 wild type restored shNRP1-treated DJM-1 cell proliferation, whereas NRP1 cytoplasmic deletion mutants did not. A co-immunoprecipitation analysis revealed that VEGF-A induced interactions between NRP1 and GIPC1, a scaffold protein, and complex formation between GIPC1 and Syx, a RhoGEF. The knockdown of GIPC1 or Syx reduced active RhoA and DJM-1 cell proliferation without affecting the MAPK or Akt pathway. C3 exoenzyme or Y27632 inhibited the VEGF-A-induced proliferation of DJM-1 cells. Conversely, the overexpression of the constitutively active form of RhoA restored the proliferation of siVEGF-A-treated DJM-1 cells. Furthermore, the inhibition of VEGF-A/NRP1 signaling upregulated p27, a CDK inhibitor. A cell-penetrating oligopeptide that targeted GIPC1/Syx complex formation inhibited the VEGF-A-induced activation of RhoA and suppressed DJM-1 cell proliferation. In conclusion, this new signaling pathway of VEGF-A/NRP1 induced cancer cell proliferation by forming a GIPC1/Syx complex that activated RhoA to degrade the p27 protein.

  15. Peroxisome proliferator-activated receptorα agonists differentially regulate inhibitor of DNA binding expression in rodents and human cells.

    Science.gov (United States)

    González, María Del Carmen; Corton, J Christopher; Acero, Nuria; Muñoz-Mingarro, Dolores; Quirós, Yolanda; Alvarez-Millán, Juan José; Herrera, Emilio; Bocos, Carlos

    2012-01-01

    Inhibitor of DNA binding (Id2) is a helix-loop-helix (HLH) transcription factor that participates in cell differentiation and proliferation. Id2 has been linked to the development of cardiovascular diseases since thiazolidinediones, antidiabetic agents and peroxisome proliferator-activated receptor (PPAR) gamma agonists, have been reported to diminish Id2 expression in human cells. We hypothesized that PPARα activators may also alter Id2 expression. Fenofibrate diminished hepatic Id2 expression in both late pregnant and unmated rats. In 24 hour fasted rats, Id2 expression was decreased under conditions known to activate PPARα. In order to determine whether the fibrate effects were mediated by PPARα, wild-type mice and PPARα-null mice were treated with Wy-14,643 (WY). WY reduced Id2 expression in wild-type mice without an effect in PPARα-null mice. In contrast, fenofibrate induced Id2 expression after 24 hours of treatment in human hepatocarcinoma cells (HepG2). MK-886, a PPARα antagonist, did not block fenofibrate-induced activation of Id2 expression, suggesting a PPARα-independent effect was involved. These findings confirm that Id2 is a gene responsive to PPARα agonists. Like other genes (apolipoprotein A-I, apolipoprotein A-V), the opposite directional transcriptional effect in rodents and a human cell line further emphasizes that PPARα agonists have different effects in rodents and humans.

  16. Regulation of the human SLC25A20 expression by peroxisome proliferator-activated receptor alpha in human hepatoblastoma cells

    Energy Technology Data Exchange (ETDEWEB)

    Tachibana, Keisuke, E-mail: nya@phs.osaka-u.ac.jp [Graduate School of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka, Suita, Osaka 565-0871 (Japan); Takeuchi, Kentaro; Inada, Hirohiko [Graduate School of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka, Suita, Osaka 565-0871 (Japan); Yamasaki, Daisuke [Graduate School of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka, Suita, Osaka 565-0871 (Japan); The Center for Advanced Medical Engineering and Informatics, Osaka University, 2-2 Yamadaoka, Suita, Osaka 565-0871 (Japan); Ishimoto, Kenji [Graduate School of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka, Suita, Osaka 565-0871 (Japan); Graduate School of Medicine, Osaka University, 2-2 Yamadaoka, Suita, Osaka 565-0871 (Japan); Tanaka, Toshiya; Hamakubo, Takao; Sakai, Juro; Kodama, Tatsuhiko [Laboratory for System Biology and Medicine, Research Center for Advanced Science and Technology, University of Tokyo, 4-6-1 Komaba, Meguro, Tokyo 153-8904 (Japan); Doi, Takefumi [Graduate School of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka, Suita, Osaka 565-0871 (Japan); The Center for Advanced Medical Engineering and Informatics, Osaka University, 2-2 Yamadaoka, Suita, Osaka 565-0871 (Japan); Graduate School of Medicine, Osaka University, 2-2 Yamadaoka, Suita, Osaka 565-0871 (Japan)

    2009-11-20

    Solute carrier family 25, member 20 (SLC25A20) is a key molecule that transfers acylcarnitine esters in exchange for free carnitine across the mitochondrial membrane in the mitochondrial {beta}-oxidation. The peroxisome proliferator-activated receptor alpha (PPAR{alpha}) is a ligand-activated transcription factor that plays an important role in the regulation of {beta}-oxidation. We previously established tetracycline-regulated human cell line that can be induced to express PPAR{alpha} and found that PPAR{alpha} induces the SLC25A20 expression. In this study, we analyzed the promoter region of the human slc25a20 gene and showed that PPAR{alpha} regulates the expression of human SLC25A20 via the peroxisome proliferator responsive element.

  17. IL-7 splicing variant IL-7{delta}5 induces human breast cancer cell proliferation via activation of PI3K/Akt pathway

    Energy Technology Data Exchange (ETDEWEB)

    Pan, Deshun [Guangdong Key Laboratory of Pharmaceutical Bioactive Substances, Guangdong Pharmaceutical University, Guangzhou, Guangdong 510006 (China); Department of Pharmaceutical science, Guangdong Pharmaceutical University, Guangzhou, Guangdong (China); Liu, Bing [Department of Pharmaceutical science, Guangdong Pharmaceutical University, Guangzhou, Guangdong (China); Jin, Xiaobao [Guangdong Key Laboratory of Pharmaceutical Bioactive Substances, Guangdong Pharmaceutical University, Guangzhou, Guangdong 510006 (China); Zhu, Jiayong, E-mail: zhujiayong888@163.com [Guangdong Key Laboratory of Pharmaceutical Bioactive Substances, Guangdong Pharmaceutical University, Guangzhou, Guangdong 510006 (China)

    2012-06-15

    Highlights: Black-Right-Pointing-Pointer This study confirms the role of IL-7{delta}5 in breast cancer cell proliferation. Black-Right-Pointing-Pointer IL-7{delta}5 promotes breast cancer cell proliferation and cell cycle progression. Black-Right-Pointing-Pointer IL-7{delta}5 promotes cell proliferation via activation of PI3K/Akt pathway. -- Abstract: Various tumor cells express interleukin 7 (IL-7) and IL-7 variants. IL-7 has been confirmed to stimulate solid tumor cell proliferation. However, the effect of IL-7 variants on tumor cell proliferation remains unclear. In this study, we evaluated the role of IL-7{delta}5 (an IL-7 variant lacking exon 5) on proliferation and cell cycle progression of human MDA-MB-231 and MCF-7 breast cancer cells. The results showed that IL-7{delta}5 promoted cell proliferation and cell cycle progression from G1 phase to G2/M phase, associated with upregulation of cyclin D1 expression and the downregulation of p27{sup kip1} expression. Mechanistically, we found that IL-7{delta}5 induced the activation of Akt. Inhibition of PI3K/Akt pathway by LY294002 reversed the proliferation and cell cycle progression of MDA-MB-231 and MCF-7 cells induced by IL-7{delta}5. In conclusion, our findings demonstrate that IL-7{delta}5 variant induces human breast cancer cell proliferation and cell cycle progression via activation of PI3K/Akt pathway. Thus, IL-7{delta}5 may be a potential target for human breast cancer therapeutics intervention.

  18. Impairments in cognition and neural precursor cell proliferation in mice expressing constitutively active glycogen synthase kinase-3

    Directory of Open Access Journals (Sweden)

    Marta ePardo

    2015-03-01

    Full Text Available ABSTRACTBrain glycogen synthase kinase-3 (GSK3 is hyperactive in several neurological conditions that involve impairments in both cognition and neurogenesis. This raises the hypotheses that hyperactive GSK3 may directly contribute to impaired cognition, and that this may be related to deficiencies in neural precursor cells (NPC. To study the effects of hyperactive GSK3 in the absence of disease influences, we compared adult hippocampal NPC proliferation and performance in three cognitive tasks in male and female wild-type mice and GSK3 knockin mice, which express constitutively active GSK3. NPC proliferation was ~40% deficient in both male and female GSK3 knockin mice compared with wild-type mice. Environmental enrichment (EE increased NPC proliferation in male, but not female, GSK3 knockin mice and wild-type mice. Male and female GSK3 knockin mice exhibited impairments in novel object recognition, temporal order memory, and coordinate spatial processing compared with gender-matched wild-type mice. EE restored impaired novel object recognition and temporal ordering in both sexes of GSK3 knockin mice, indicating that this repair was not dependent on NPC proliferation, which was not increased by EE in female GSK3 knockin mice. Acute 1 hr pretreatment with the GSK3 inhibitor TDZD-8 also improved novel object recognition and temporal ordering in male and female GSK3 knockin mice. These findings demonstrate that hyperactive GSK3 is sufficient to impair adult hippocampal NPC proliferation and to impair performance in three cognitive tasks in both male and female mice, but these changes in NPC proliferation do not directly regulate novel object recognition and temporal ordering tasks.

  19. Adolescent olanzapine sensitization is correlated with hippocampal stem cell proliferation in a maternal immune activation rat model of schizophrenia.

    Science.gov (United States)

    Chou, Shinnyi; Jones, Sean; Li, Ming

    2015-08-27

    Previous work established that repeated olanzapine (OLZ) administration in normal adolescent rats induces a sensitization effect (i.e. increased behavioral responsiveness to drug re-exposure) in the conditioned avoidance response (CAR) model. However, it is unclear whether the same phenomenon can be detected in animal models of schizophrenia. The present study explored the generalizability of OLZ sensitization from healthy animals to a preclinical neuroinflammatory model of schizophrenia in the CAR. Maternal immune activation (MIA) was induced via polyinosinic:polycytidylic acid (PolyI:C) administration into pregnant dams. Behavioral assessments of offspring first identified decreased maternal separation-induced pup ultrasonic vocalizations and increased amphetamine-induced hyperlocomotion in animals prenatally exposed to PolyI:C. In addition, repeated adolescent OLZ administration confirmed the generalizability of the sensitization phenomenon. Using the CAR test, adolescent MIA animals displayed a similar increase in behavioral responsiveness after repeated OLZ exposure during both the repeated drug test days as well as a subsequent challenge test. Neurobiologically, few studies examining the relationship between hippocampal cell proliferation and survival and either antipsychotic exposure or MIA have incorporated concurrent behavioral changes. Thus, the current study also sought to reveal the correlation between OLZ behavioral sensitization in the CAR and hippocampal cell proliferation and survival. 5'-bromodeoxyuridine immunohistochemistry identified a positive correlation between the magnitude of OLZ sensitization (i.e. change in avoidance suppression induced by OLZ across days) and hippocampal cell proliferation. The implications of the relationship between behavioral and neurobiological results are discussed.

  20. Calcineurin/nuclear factor of activated T cells-coupled vanilliod transient receptor potential channel 4 ca2+ sparklets stimulate airway smooth muscle cell proliferation.

    Science.gov (United States)

    Zhao, Limin; Sullivan, Michelle N; Chase, Marlee; Gonzales, Albert L; Earley, Scott

    2014-06-01

    Proliferation of airway smooth muscle cells (ASMCs) contributes to the remodeling and irreversible obstruction of airways during severe asthma, but the mechanisms underlying this disease process are poorly understood. Here we tested the hypothesis that Ca(2+) influx through the vanilliod transient receptor potential channel (TRPV) 4 stimulates ASMC proliferation. We found that synthetic and endogenous TRPV4 agonists increase proliferation of primary ASMCs. Furthermore, we demonstrate that Ca(2+) influx through individual TRPV4 channels produces Ca(2+) microdomains in ASMCs, called "TRPV4 Ca(2+) sparklets." We also show that TRPV4 channels colocalize with the Ca(2+)/calmodulin-dependent protein phosphatase calcineurin in ASMCs. Activated calcineurin dephosphorylates nuclear factor of activated T cells (NFAT) transcription factors cytosolic (c) to allow nuclear translocation and activation of synthetic transcriptional pathways. We show that ASMC proliferation in response to TRPV4 activity is associated with calcineurin-dependent nuclear translocation of the NFATc3 isoform tagged with green florescent protein. Our findings suggest that Ca(2+) microdomains created by TRPV4 Ca(2+) sparklets activate calcineurin to stimulate nuclear translocation of NFAT and ASMC proliferation. These findings further suggest that inhibition of TRPV4 could diminish asthma-induced airway remodeling.

  1. Icariin inhibits oxidized low-density lipoprotein-induced proliferation of vascular smooth muscle cells by suppressing activation of extracellular signal-regulated kinase 1/2 and expression of proliferating cell nuclear antigen.

    Science.gov (United States)

    Hu, Yanwu; Liu, Kai; Yan, Mengtong; Zhang, Yang; Wang, Yadi; Ren, Liqun

    2016-03-01

    Icariin, a flavonoid isolated from the traditional Chinese herbal medicine Epimedium brevicornum Maxim, has been shown to possess anti-inflammatory, anti‑oxidant and anti-atherosclerotic activities in vivo and in vitro. The aim of the present study was to investigate the effects of icariin on oxidized low‑density lipoprotein (ox-LDL)-induced proliferation of vascular smooth muscle cells (VSMCs) and the possible underlying mechanism. VSMCs were cultured and pre‑treated with various concentrations of icariin (0, 10, 20 or 40 µm) prior to stimulation by ox‑LDL (50 µg/ml). Cell proliferation was evaluated by an MTT assay. Flow cytometry was used to study the influence of icariin on the cell cycle. Proliferating cell nuclear antigen (PCNA) expression and phosphorylation levels of extracellular signal-regulated kinase (ERK)1/2 were detected by western blot analysis. The results indicated that icariin significantly inhibited ox‑LDL‑induced proliferation of VSMCs and phosphorylation of ERK1/2. Furthermore, icariin also blocked the ox‑LDL‑induced cell‑cycle progression at G1/S‑interphase and downregulated the expression of PCNA in VSMCs. In conclusion, the present study indicated for the first time that icariin reduced the amount of ox‑LDL‑induced proliferation of VSMCs through suppression of PCNA expression and inactivation of ERK1/2.

  2. Human mesenchymal stem cell proliferation is regulated by PGE2 through differential activation of cAMP-dependent protein kinase isoforms

    DEFF Research Database (Denmark)

    Kleiveland, Charlotte Ramstad; Kassem, Moustapha; Lea, Tor

    2008-01-01

    . Furthermore, PGE2 treatment leads to enhanced nuclear translocation of beta-catenin, thus influencing cell proliferation. The presence of two PKA isoforms, types I and II, prompted us to investigate their individual contribution in PGE2-mediated regulation of proliferation. Specific activation of PKA type II...... of PGE2 on proliferation of hMSC. We here demonstrate that one of the main control molecules in the Wnt pathway, GSK-3 beta, is phosphorylated at the negative regulatory site ser-9 after treating the cells with PGE2. This phosphorylation is mediated by elevation of cAMP and subsequent activation of PKA...... with synthetic cAMP analogues, resulted in enhancement of proliferation. On the other side, we found that treatment of hMSC with high concentrations of PGE2 inhibited cell proliferation by arresting the cells in G0/G1 phase, an effect we found to be mediated by PKA I. Hence, the two different PKA isoforms seem...

  3. In Vitro Antioxidant, Anticoagulant and Antimicrobial Activity and in Inhibition of Cancer Cell Proliferation by Xylan Extracted from Corn Cobs

    Directory of Open Access Journals (Sweden)

    Hugo Alexandre Oliveira Rocha

    2011-12-01

    Full Text Available Xylan is one of most abundant polymer after cellulose. However, its potential has yet to be completely recognized. Corn cobs contain a considerable reservoir of xylan. The aim of this work was to study some of the biological activities of xylan obtained from corn cobs after alkaline extraction enhanced by ultrasonication. Physical chemistry and infrared analyses showed 130 kDa heteroxylan containing mainly xylose:arabinose: galactose:glucose (5.0:1.5:2.0:1.2. Xylan obtained exhibited total antioxidant activity corresponding to 48.5 mg of ascorbic acid equivalent/g of xylan. Furthermore, xylan displayed high ferric chelating activity (70% at 2 mg/mL. Xylan also showed anticoagulant activity in aPTT test. In antimicrobial assay, the polysaccharide significantly inhibited bacterial growth of Klebsiella pneumoniae. In a test with normal and tumor human cells, after 72 h, only HeLa tumor cell proliferation was inhibited (p < 0.05 in a dose-dependent manner by xylan, reaching saturation at around 2 mg/mL, whereas 3T3 normal cell proliferation was not affected. The results suggest that it has potential clinical applications as antioxidant, anticoagulant, antimicrobial and antiproliferative compounds.

  4. Capsaicin enhances anti-proliferation efficacy of pirarubicin via activating TRPV1 and inhibiting PCNA nuclear translocation in 5637 cells.

    Science.gov (United States)

    Zheng, Long; Chen, Jiaqi; Ma, Zhenkun; Liu, Wei; Yang, Fei; Yang, Zhao; Wang, Ke; Wang, Xinyang; He, Dalin; Li, Lei; Zeng, Jin

    2016-01-01

    The recurrence of bladder cancer after surgery with or without chemotherapy remains a major challenge in bladder cancer treatment. Previous studies have shown that transient receptor potential vanilloid 1 (TRPV1) acts as a tumor suppressor through inducing apoptosis in bladder cancer cells. However, whether activation of TRPV1 has any synergistic effects with pirarubicin (THP), one of main drugs used in urinary bladder instillation chemotherapy to improve chemotherapeutic efficacy has remained elusive. The present study verified that TRPV1 was differentially expressed in bladder cancer cell lines. Furthermore, activation of TRPV1 by capsaicin was shown to induce growth inhibition of 5637 cells in which TRPV1 was highly expressed, while the growth of T24 cells, which express TRPV1 at low levels, was not affected. In addition, the present study demonstrated that activation of TRPV1 enhanced the anti‑proliferative effects of pirarubicin using an MTT assay and cell cycle analysis. Finally, immunofluorescent microscopy revealed that activation of TRPV1 prevented the translocation of proliferating cell nuclear antigen to the nucleus. This phenomenon was reversed by pre‑treatment with capsazepine, a specific TRPV1 antagonist. In conclusion, the present study confirmed the anti‑tumor activity of TRPV1 against bladder cancer. Activation of TRPV1 may be applied as a novel strategy to treat bladder cancer or enhance the therapeutic efficacy of traditional chemotherapeutic drugs.

  5. Knockdown of Pokemon protein expression inhibits hepatocellular carcinoma cell proliferation by suppression of AKT activity.

    Science.gov (United States)

    Zhu, Xiaosan; Dai, Yichen; Chen, Zhangxin; Xie, Junpei; Zeng, Wei; Lin, Yuanyuan

    2013-01-01

    Overexpression of Pokemon, which is an erythroid myeloid ontogenic factor protein, occurs in different cancers, including hepatocellular carcinoma (HCC). Pokemon is also reported to have an oncogenic activity in various human cancers. This study investigated the effect of Pokemon knockdown on the regulation of HCC growth. POK shRNA suppressed the expression of Pokemon protein in HepG2 cells compared to the negative control vector-transfected HCC cells. Pokemon knockdown also reduced HCC cell viability and enhanced cisplatin-induced apoptosis in HCC cells. AKT activation and the expression of various cell cycle-related genes were inhibited following Pokemon knockdown. These data demonstrate that Pokemon may play a role in HCC progression, suggesting that inhibition of Pokemon expression using Pokemon shRNA should be further evaluated as a novel target for the control of HCC. PMID:23924858

  6. Sodium tanshinone IIA silate inhibits high glucose-induced vascular smooth muscle cell proliferation and migration through activation of AMP-activated protein kinase.

    Directory of Open Access Journals (Sweden)

    Wen-yu Wu

    Full Text Available The proliferation of vascular smooth muscle cells may perform a crucial role in the pathogenesis of diabetic vascular disease. AMPK additionally exerts several salutary effects on vascular function and improves vascular abnormalities. The current study sought to determine whether sodium tanshinone IIA silate (STS has an inhibitory effect on vascular smooth muscle cell (VSMC proliferation and migration under high glucose conditions mimicking diabetes without dyslipidemia, and establish the underlying mechanism. In this study, STS promoted the phosphorylation of AMP-activated protein kinase (AMPK at T172 in VSMCs. VSMC proliferation was enhanced under high glucose (25 mM glucose, HG versus normal glucose conditions (5.5 mM glucose, NG, and this increase was inhibited significantly by STS treatment. We utilized western blotting analysis to evaluate the effects of STS on cell-cycle regulatory proteins and found that STS increased the expression of p53 and the Cdk inhibitor, p21, subsequent decreased the expression of cell cycle-associated protein, cyclin D1. We further observed that STS arrested cell cycle progression at the G0/G1 phase. Additionally, expression and enzymatic activity of MMP-2, translocation of NF-κB, as well as VSMC migration were suppressed in the presence of STS. Notably, Compound C (CC, a specific inhibitor of AMPK, as well as AMPK siRNA blocked STS-mediated inhibition of VSMC proliferation and migration. We further evaluated its potential for activating AMPK in aortas in animal models of type 2 diabetes and found that Oral administration of STS for 10 days resulted in activation of AMPK in aortas from ob/ob or db/db mice. In conclusion, STS inhibits high glucose-induced VSMC proliferation and migration, possibly through AMPK activation. The growth suppression effect may be attributable to activation of AMPK-p53-p21 signaling, and the inhibitory effect on migration to the AMPK/NF-κB signaling axis.

  7. Cucurbitane Triterpenoid from Momordica charantia Induces Apoptosis and Autophagy in Breast Cancer Cells, in Part, through Peroxisome Proliferator-Activated Receptor γ Activation

    OpenAIRE

    Jing-Ru Weng; Li-Yuan Bai; Chang-Fang Chiu; Jing-Lan Hu; Shih-Jiuan Chiu; Chia-Yung Wu

    2013-01-01

    Although the antitumor activity of the crude extract of wild bitter gourd (Momordica charantia L.) has been reported, its bioactive constituents and the underlying mechanism remain undefined. Here, we report that 3 β ,7 β -dihydroxy-25-methoxycucurbita-5,23-diene-19-al (DMC), a cucurbitane-type triterpene isolated from wild bitter gourd, induced apoptotic death in breast cancer cells through peroxisome proliferator-activated receptor (PPAR) γ activation. Luciferase reporter assays indicated t...

  8. Sodium arsenite-induced inhibition of cell proliferation is related to inhibition of IL-2 mRNA expression in mouse activated T cells

    Energy Technology Data Exchange (ETDEWEB)

    Conde, Patricia; Acosta-Saavedra, Leonor C.; Calderon-Aranda, Emma S. [Centro de Investigacion y de Estudios Avanzados, CINVESTAV, Seccion Toxicologia, P.O. Box 14-740, Mexico, D.F. (Mexico); Goytia-Acevedo, Raquel C. [Universidad Juarez del Estado de Durango, Facultad de Medicina, Gomez Palacio, Durango (Mexico)

    2007-04-15

    A proposed mechanism for the As-induced inhibition of cell proliferation is the inhibition of IL-2 secretion. However, the effects of arsenite on IL-2 mRNA expression or on the ERK pathway in activated-T cells have not yet been described. We examined the effect of arsenite on IL-2 mRNA expression, cell activation and proliferation in PHA-stimulated murine lymphocytes. Arsenite (1 and 10 {mu}M) decreased IL-2 mRNA expression, IL-2 secretion and cell proliferation. Arsenite (10 {mu}M) strongly inhibited ERK-phosphorylation. However, the partial inhibition (50%) of IL-2 mRNA produced by 1 {mu}M, consistent with the effects on IL-2 secretion and cell proliferation, could not be explained by the inhibition of ERK-phosphorylation, which was not affected at this concentration. The inhibition of IL-2 mRNA expression caused by 1 {mu}M could be associated to effects on pathways located downstream or parallel to ERK. Arsenite also decreased early activation (surface CD69{sup +} expression) in both CD4{sup +} and CD8{sup +}, and decreased total CD8{sup +} count without significantly affecting CD4{sup +}, supporting that the cellular immune response mediated by cytotoxic T cells is an arsenic target. Thus, our results suggest that arsenite decreases IL-2 mRNA levels and T-cell activation and proliferation. However, further studies on the effects of arsenite on IL-2 gene transcription and IL-2 mRNA stability are needed. (orig.)

  9. REX-1 expression and p38 MAPK activation status can determine proliferation/differentiation fates in human mesenchymal stem cells.

    Directory of Open Access Journals (Sweden)

    Dilli Ram Bhandari

    Full Text Available BACKGROUND: REX1/ZFP42 is a well-known embryonic stem cell (ESC marker. However, the role of REX1, itself, is relatively unknown because the function of REX1 has only been reported in the differentiation of ESCs via STAT signaling pathways. Human mesenchymal stem cells (hMSCs isolated from young tissues and cancer cells express REX1. METHODOLOGY/PRINCIPAL FINDING: Human umbilical cord blood-derived MSCs (hUCB-MSCs and adipose tissue-derived MSCs (hAD-MSCs strongly express REX1 and have a lower activation status of p38 MAPK, but bone marrow-derived MSCs (hBM-MSCs have weak REX1 expression and higher activation of p38 MAPK. These results indicated that REX1 expression in hMSCs was positively correlated with proliferation rates but inversely correlated with the phosphorylation of p38 MAPK. In hUCB-MSCs, the roles of REX1 and p38 MAPK were investigated, and a knockdown study was performed using a lentiviral vector-based small hairpin RNA (shRNA. After REX1 knockdown, decreased cell proliferation was observed. In REX1 knocked-down hUCB-MSCs, the osteogenic differentiation ability deteriorated, but the adipogenic potential increased or was similar to that observed in the controls. The phosphorylation of p38 MAPK in hUCB-MSCs significantly increased after REX1 knockdown. After p38 MAPK inhibitor treatment, the cell growth in REX1 knocked-down hUCB-MSCs almost recovered, and the suppressed expression levels of CDK2 and CCND1 were also restored. The expression of MKK3, an upstream regulator of p38 MAPK, significantly increased in REX1 knocked-down hUCB-MSCs. The direct binding of REX1 to the MKK3 gene was confirmed by a chromatin immunoprecipitation (ChIP assay. CONCLUSIONS/SIGNIFICANCE: These findings showed that REX1 regulates the proliferation/differentiation of hMSCs through the suppression of p38 MAPK signaling via the direct suppression of MKK3. Therefore, p38 MAPK and REX-1 status can determine the cell fate of adult stem cells (ASCs. These

  10. Matrine reduces the proliferation and invasion of colorectal cancer cells via reducing the activity of p38 signaling pathway.

    Science.gov (United States)

    Ren, Hongtao; Zhang, Shuqun; Ma, Hongbing; Wang, Yali; Liu, Di; Wang, Xijing; Wang, Zhongwei

    2014-12-01

    Matrine has been used in anti-inflammatory and anti-cancer therapies for a long time. However, the anti-metastatic effect and related mechanism(s) in colorectal cancer (CRC) are still unclear. In this study, we investigated whether the administration of matrine could inhibit the proliferation, motility, and invasion of human CRC cells via regulating p38 signaling pathway. Results showed that matrine inhibited migration and invasion of CRC cells in vitro and in vivo. Additionally, after being treated with matrine for 24 h, the expression levels of matrix metalloproteinase-2 (MMP-2) and MMP-9 as well as proteinase activity in CRC cells were reduced in a dose-dependent manner. Moreover, matrine reduced the phosphorylation level of p38 obviously. Combined treatment with p38 inhibitor (SB203580) and matrine resulted in a synergistic reduction of invasion as well as MMP-2/-9 expression in CRC cells. It was also found that matrine inhibited the proliferation and metastasis of CRC tumor in vivo. In conclusion, p38 signaling pathway may involve in matrine's inhibitory effects on migration and invasion of CRC cells by reducing the expression of MMP-2/-9, suggesting that matrine may be a potential therapeutic agent for CRC.

  11. Inhibition of testicular embryonal carcinoma cell tumorigenicity by peroxisome proliferator-activated receptor-β/δ- and retinoic acid receptor-dependent mechanisms

    OpenAIRE

    Yao, Pei-Li; Chen, Li Ping; Dobrzański, Tomasz P.; Phillips, Dylan A.; Zhu, Bokai; Kang, Boo-Hyon; Frank J. Gonzalez; Peters, Jeffrey M.

    2015-01-01

    Peroxisome proliferator-activated receptor-β/δ (PPARβ/δ) has important physiological functions in control of cell growth, lipid and glucose homeostasis, differentiation and inflammation. To investigate the role of PPARβ/δ in cancer, stable human testicular embryonal carcinoma cell lines were developed that constitutively express PPARβ/δ. Expression of PPARβ/δ caused enhanced activation of the receptor, and this significantly decreased proliferation, migration, invasion, anchorage-independent ...

  12. Peroxisome Proliferator-Activated Receptor-γActivated by Ligands Can Inhibit Human Lung Cancer Cell Growth through Induction of Apoptosis

    Institute of Scientific and Technical Information of China (English)

    张敏; 邹萍; 白明; 金阳; 陶晓南

    2003-01-01

    Summary: To study the expression of peroxisome proliferator-activated receptor-γ(PPAR-γ) in lungcancer cells, and to testify if the PPAR-γ agonists can inhibit human lung cancer cell growth throughinduction of apoptosis, PPAR-γ was detected in two lung cancer cell lines by RT-PCR and immuno-histochemistry, the inhibition of human lung cancer cell growth was investigated by MTT and cellcounts, and the apoptosis was assessed by TUNEL. The results showed that: (1) PPAR-γ expressedon two lung cancer cell lines; (2) PPAR-γ activated by ligands could inhibit human lung cancer cellgrowth remarkably; (3) PPAR-γ agonists could induce apoptosis to inhibit lung cancer cell growth.It was concluded that PPAR-γ expressed in lung cancer cell can be activated by ligands and can inhib-it lung cancer cell growth through induction of apoptosis.

  13. Aspirin-induced AMP-activated protein kinase activation regulates the proliferation of vascular smooth muscle cells from spontaneously hypertensive rats

    Energy Technology Data Exchange (ETDEWEB)

    Sung, Jin Young [Department of Pharmacology, College of Medicine, Yeungnam University, Daegu 705-717 (Korea, Republic of); Choi, Hyoung Chul, E-mail: hcchoi@med.yu.ac.kr [Department of Pharmacology, College of Medicine, Yeungnam University, Daegu 705-717 (Korea, Republic of)

    2011-05-06

    Highlights: {yields} Aspirin-induced AMPK phosphorylation was greater in VSMC from SHR than WKY. {yields} Aspirin-induced AMPK phosphorylation inhibited proliferation of VSMC from SHR. {yields} Low basal AMPK phosphorylation in SHR elicits increased VSMC proliferation. {yields} Inhibition of AMPK restored decreased VSMC proliferation by aspirin in SHR. {yields} Aspirin exerts anti-proliferative effect through AMPK activation in VSMC from SHR. -- Abstract: Acetylsalicylic acid (aspirin), used to reduce risk of cardiovascular disease, plays an important role in the regulation of cellular proliferation. However, mechanisms responsible for aspirin-induced growth inhibition are not fully understood. Here, we investigated whether aspirin may exert therapeutic effects via AMP-activated protein kinase (AMPK) activation in vascular smooth muscle cells (VSMC) from wistar kyoto rats (WKY) and spontaneously hypertensive rats (SHR). Aspirin increased AMPK and acetyl-CoA carboxylase phosphorylation in a time- and dose-dependent manner in VSMCs from WKY and SHR, but with greater efficacy in SHR. In SHR, a low basal phosphorylation status of AMPK resulted in increased VSMC proliferation and aspirin-induced AMPK phosphorylation inhibited proliferation of VSMCs. Compound C, an AMPK inhibitor, and AMPK siRNA reduced the aspirin-mediated inhibition of VSMC proliferation, this effect was more pronounced in SHR than in WKY. In VSMCs from SHR, aspirin increased p53 and p21 expression and inhibited the expression of cell cycle associated proteins, such as p-Rb, cyclin D, and cyclin E. These results indicate that in SHR VSMCs aspirin exerts anti-proliferative effects through the induction of AMPK phosphorylation.

  14. Inhibitory effects of low molecular weight polyphenolics from Inonotus obliquus on human DNA topoisomerase activity and cancer cell proliferation.

    Science.gov (United States)

    Kuriyama, Isoko; Nakajima, Yuki; Nishida, Hiroshi; Konishi, Tetsuya; Takeuchi, Toshifumi; Sugawara, Fumio; Yoshida, Hiromi; Mizushina, Yoshiyuki

    2013-08-01

    Low molecular weight (LMW) polyphenolics containing a polyhydroxylated benzyl moiety are abundant in medicinal plants. In the present study, we report on the activities of seven LMW polyphenolics isolated from Inonotus obliquus, a medicinal mushroom. The isolated compounds included caffeic acid (CA), 3,4-dihydroxybenzalacetone (DBL), gallic acid, syringic acid, protocatechuic acid, 3,4-dihydroxybenzaldehyde and 2,5-dihydroxyterephthalic acid. We analyzed their inhibitory effects on DNA polymerase (pol) and DNA topoisomerase (topo), and their effects on human cancer cell growth. All isolated compounds inhibited human topo II activity; the most potent were DBL and CA, which contain a catechol propanoid moiety. CA and DBL inhibited the activity of human topo I, whereas other compounds had no effect. No compound modulated the activities of 11 mammalian pol species or other DNA metabolic enzymes, including T7 RNA polymerase, mouse IMP dehydrogenase (type II), T4 polynucleotide kinase and bovine deoxyribonuclease I. CA and DBL markedly suppressed the proliferation of human colon HCT116 carcinoma cells with an LD50 of 70.0 and 49.4 µM, respectively, and halted the cell cycle in the G2/M phase. The suppressive effect of these compounds on cancer cell growth correlated with their ability to inhibit topo II. These results suggest that CA- and DBL-dependent decreases in cell proliferation are due to the inhibition of cellular topo II. The mechanism of action of these catechol propanoid compounds and the implication for their use as anticancer agents are discussed. PMID:23799608

  15. The splicing activator DAZAP1 integrates splicing control into MEK/Erk-regulated cell proliferation and migration

    Science.gov (United States)

    Choudhury, Rajarshi; Roy, Sreerupa Ghose; Tsai, Yihsuan S.; Tripathy, Ashutosh; Graves, Lee M.; Wang, Zefeng

    2014-01-01

    Alternative splicing of pre-messenger RNA (mRNA) is a critical stage of gene regulation in response to environmental stimuli. Here we show that DAZAP1, an RNA-binding protein involved in mammalian development and spermatogenesis, promotes inclusion of weak exons through specific recognition of diverse cis-elements. The carboxy-terminal proline-rich domain of DAZAP1 interacts with and neutralizes general splicing inhibitors, and is sufficient to activate splicing when recruited to pre-mRNA. This domain is phosphorylated by the MEK/Erk (extracellular signal-regulated protein kinase) pathway and this modification is essential for the splicing regulatory activity and the nuclear/cytoplasmic translocation of DAZAP1. Using mRNA-seq, we identify endogenous splicing events regulated by DAZAP1, many of which are involved in maintaining cell growth. Knockdown or over-expression of DAZAP1 causes a cell proliferation defect. Taken together, these studies reveal a molecular mechanism that integrates splicing control into MEK/Erk-regulated cell proliferation.

  16. Peroxisome proliferator-activated receptor gamma B cell-specific deficient mice have an impaired antibody response1

    Science.gov (United States)

    Ramon, Sesquile; Bancos, Simona; Thatcher, Thomas H.; Murant, Thomas I.; Moshkani, Safiehkhatoon; Sahler, Julie M.; Bottaro, Andrea; Sime, Patricia J.; Phipps, Richard P.

    2012-01-01

    Peroxisome proliferator-activated receptors (PPARs) are members of the nuclear hormone receptor superfamily. PPARγ, a ligand activated transcription factor, has important anti-inflammatory and anti-proliferative functions and it has been associated with diseases including diabetes, scarring and atherosclerosis among others. PPARγ is expressed in most bone marrow derived cells and influences their function. PPARγ ligands can stimulate human B cell differentiation and promote antibody production. A knowledge gap is that the role of PPARγ in B cells under physiological conditions is not known. We developed a new B cell-specific PPARγ (B-PPARγ) knockout mouse and explored the role of PPARγ during both the primary and secondary immune response. Here, we show that PPARγ deficiency in B cells decreases germinal center B cells and plasma cell development as well as the levels of circulating antigen-specific antibodies during a primary challenge. Inability to generate germinal center B cells and plasma cells is correlated to decreased MHC class II expression and decreased Bcl-6 and Blimp-1 levels. Furthermore, B-PPARγ-deficient mice have an impaired memory response, characterized by low titers of antigen-specific antibodies and low numbers of antigen-experienced antibody-secreting cells. However, B-PPARγ-deficient mice have no differences in B cell population distribution within neither primary nor secondary lymphoid organs during development. This is the first report to show under physiological conditions that PPARγ expression in B cells is required for an efficient B cell-mediated immune response as it regulates B cell differentiation and antibody production. PMID:23041568

  17. Peroxisome proliferator-activated receptor γ B cell-specific-deficient mice have an impaired antibody response.

    Science.gov (United States)

    Ramon, Sesquile; Bancos, Simona; Thatcher, Thomas H; Murant, Thomas I; Moshkani, Safiehkhatoon; Sahler, Julie M; Bottaro, Andrea; Sime, Patricia J; Phipps, Richard P

    2012-11-15

    Peroxisome proliferator-activated receptors (PPARs) are members of the nuclear hormone receptor superfamily. PPARγ, a ligand-activated transcription factor, has important anti-inflammatory and antiproliferative functions, and it has been associated with diseases including diabetes, scarring, and atherosclerosis, among others. PPARγ is expressed in most bone marrow-derived cells and influences their function. PPARγ ligands can stimulate human B cell differentiation and promote Ab production. A knowledge gap is that the role of PPARγ in B cells under physiological conditions is not known. We developed a new B cell-specific PPARγ (B-PPARγ) knockout mouse and explored the role of PPARγ during both the primary and secondary immune response. In this article, we show that PPARγ deficiency in B cells decreases germinal center B cells and plasma cell development, as well as the levels of circulating Ag-specific Abs during a primary challenge. Inability to generate germinal center B cells and plasma cells is correlated to decreased MHC class II expression and decreased Bcl-6 and Blimp-1 levels. Furthermore, B-PPARγ-deficient mice have an impaired memory response, characterized by low titers of Ag-specific Abs and low numbers of Ag-experienced, Ab-secreting cells. However, B-PPARγ-deficient mice have no differences in B cell population distribution within primary or secondary lymphoid organs during development. This is the first report, to our knowledge, to show that, under physiological conditions, PPARγ expression in B cells is required for an efficient B cell-mediated immune response as it regulates B cell differentiation and Ab production.

  18. Neural stem cell activation and glial proliferation in the hippocampal CA3 region of posttraumatic epileptic rats

    Institute of Scientific and Technical Information of China (English)

    Yuanxiang Lin; Kun Lin; Dezhi Kang; Feng Wang

    2011-01-01

    The present study observed the dynamic expression of CD133, nuclear factor-κB and glial fibrillary acidic protein in the hippocampal CA3 area of the experimental posttraumatic epilepsy rats to investigate whether gliosis occurs after posttraumatic epilepsy. CD133 and nuclear factor-κB expression was increased at 1 day after posttraumatic epilepsy, peaked at 7 days, and gradually decreased up to 14 days, as seen by double-immunohistochemical staining. Glial fibrillary acidic protein/nuclear factor-κB double-labeled cells increased with time and peaked at 14 days after posttraumatic epilepsy. Results show that activation of hippocampal neural stem cells and glial proliferation after posttraumatic epilepsy-induced oxidative stress increases hippocampal glial cell density.

  19. Engineered Biomaterials Control Differentiation and Proliferation of Human-Embryonic-Stem-Cell-Derived Cardiomyocytes via Timed Notch Activation

    Directory of Open Access Journals (Sweden)

    Jason C. Tung

    2014-03-01

    Full Text Available For cell-based treatments of myocardial infarction, a better understanding of key developmental signaling pathways and more robust techniques for producing cardiomyocytes are required. Manipulation of Notch signaling has promise as it plays an important role during cardiovascular development, but previous studies presented conflicting results that Notch activation both positively and negatively regulates cardiogenesis. We developed surface- and microparticle-based Notch-signaling biomaterials that function in a time-specific activation-tunable manner, enabling precise investigation of Notch activation at specific developmental stages. Using our technologies, a biphasic effect of Notch activation on cardiac differentiation was found: early activation in undifferentiated human embryonic stem cells (hESCs promotes ectodermal differentiation, activation in specified cardiovascular progenitor cells increases cardiac differentiation. Signaling also induces cardiomyocyte proliferation, and repeated doses of Notch-signaling microparticles further enhance cardiomyocyte population size. These results highlight the diverse effects of Notch activation during cardiac development and provide approaches for generating large quantities of cardiomyocytes.

  20. Epigenetic regulation of proliferation and invasion in hepatocellular carcinoma cells by CBP/p300 histone acetyltransferase activity.

    Science.gov (United States)

    Inagaki, Yuji; Shiraki, Katsuya; Sugimoto, Kazushi; Yada, Takazumi; Tameda, Masahiko; Ogura, Suguru; Yamamoto, Norihiko; Takei, Yoshiyuki; Ito, Masaaki

    2016-02-01

    Altered epigenetic control of gene expression plays a substantial role in tumor development and progression. Accumulating studies suggest that somatic mutations of CREB binding proteins (CBP)/p300 occur in some cancer cells. CBP/p300 possess histone acetyltransferase (HAT) activity, and are involved in many cellular processes. In this study, we investigated the expression and functional role of CBP/p300 in hepatocellular carcinoma (HCC) using the specific inhibitor C646 of CBP/p300 HAT activity. We examined its effect on several apoptosis-related proteins and invasion-related genes. The results showed that CBP/p300 were highly expressed in HCC tissues and that expression of p300, but not of CBP, was strongly correlated with the malignant character of HCC. C646 inhibited proliferation of HCC cell lines in a dose dependent manner. C646 significantly augmented TRAIL-induced apoptotic sensitivity, which was accompanied by reduced levels of survivin, in HepG2, HLE and SK-HEP1 cells. C646 significantly inhibited invasion of Huh7, HLE and SK-HEP1 cells. The level of matrix metallopeptidase 15 (MMP15) mRNA expression was significantly reduced, whereas the level of laminin alpha 3 (LAMA3) and secreted phosphoprotein 1 (SPP1) mRNA expression was significantly increased in Huh7 cells following exposure to C646. In conclusion, our results suggest that CBP/p300 HAT activity has an important role in malignant transformation, proliferation, apoptotic sensitivity and invasion in HCC. CBP/p300 could be a promising therapeutic target in HCC. PMID:26676548

  1. FoxP3 inhibits proliferation and induces apoptosis of gastric cancer cells by activating the apoptotic signaling pathway

    International Nuclear Information System (INIS)

    Highlights: ► The article revealed FoxP3 gene function in gastric cancer firstly. ► Present the novel roles of FoxP3 in inhibiting proliferation and promoting apoptosis in gastric cancer cells. ► Overexpression of FoxP3 increased proapoptotic molecules and repressed antiapoptotic molecules. ► Silencing of FoxP3 reduced the expression of proapoptotic genes, such as PARP, caspase-3 and caspase-9. ► FoxP3 is sufficient for activating the apoptotic signaling pathway. -- Abstract: Forkhead Box Protein 3 (FoxP3) was identified as a key transcription factor to the occurring and function of the regulatory T cells (Tregs). However, limited evidence indicated its function in tumor cells. To elucidate the precise roles and underlying molecular mechanism of FoxP3 in gastric cancer (GC), we examined the expression of FoxP3 and the consequences of interfering with FoxP3 gene in human GC cell lines, AGS and MKN45, by multiple cellular and molecular approaches, such as immunofluorescence, gene transfection, CCK-8 assay, clone formation assay, TUNEL assay, Flow cytometry, immunoassay and quantities polymerase chain reaction (PCR). As a result, FoxP3 was expressed both in nucleus and cytoplasm of GC cells. Up-regulation of FoxP3 inhibited cell proliferation and promoted cell apoptosis. Overexpression of FoxP3 increased the protein and mRNA levels of proapoptotic molecules, such as poly ADP-ribose polymerase1 (PARP), caspase-3 and caspase-9, and repressed the expression of antiapoptotic molecules, such as cellular inhibitor of apoptosis-1 (c-IAP1) and the long isoform of B cell leukemia/lymphoma-2 (Bcl-2). Furthermore, silencing of FoxP3 by siRNA in GC cells reduced the expression of proapoptotic genes, such as PARP, caspase-3 and caspase-9. Collectively, our findings identify the novel roles of FoxP3 in inhibiting proliferation and inducing apoptosis in GC cells by regulating apoptotic signaling, which could be a promising therapeutic approach for gastric cancer.

  2. FoxP3 inhibits proliferation and induces apoptosis of gastric cancer cells by activating the apoptotic signaling pathway

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Gui-Fen [Department of Gastroenterology, Zhongshan Hospital, Fudan University, Shanghai (China); Chen, Shi-Yao, E-mail: shiyao_chen@163.com [Department of Gastroenterology, Zhongshan Hospital, Fudan University, Shanghai (China); Endoscopy Center, Zhongshan Hospital, Fudan University, Shanghai (China); Sun, Zhi-Rong [Department of Anesthesiology, Cancer Center, Fudan University, Shanghai (China); Miao, Qing; Liu, Yi-Mei; Zeng, Xiao-Qing; Luo, Tian-Cheng [Department of Gastroenterology, Zhongshan Hospital, Fudan University, Shanghai (China); Ma, Li-Li; Lian, Jing-Jing [Endoscopy Center, Zhongshan Hospital, Fudan University, Shanghai (China); Song, Dong-Li [Biomedical Research Center, Zhongshan Hospital, Fudan University, Shanghai (China)

    2013-01-11

    Highlights: Black-Right-Pointing-Pointer The article revealed FoxP3 gene function in gastric cancer firstly. Black-Right-Pointing-Pointer Present the novel roles of FoxP3 in inhibiting proliferation and promoting apoptosis in gastric cancer cells. Black-Right-Pointing-Pointer Overexpression of FoxP3 increased proapoptotic molecules and repressed antiapoptotic molecules. Black-Right-Pointing-Pointer Silencing of FoxP3 reduced the expression of proapoptotic genes, such as PARP, caspase-3 and caspase-9. Black-Right-Pointing-Pointer FoxP3 is sufficient for activating the apoptotic signaling pathway. -- Abstract: Forkhead Box Protein 3 (FoxP3) was identified as a key transcription factor to the occurring and function of the regulatory T cells (Tregs). However, limited evidence indicated its function in tumor cells. To elucidate the precise roles and underlying molecular mechanism of FoxP3 in gastric cancer (GC), we examined the expression of FoxP3 and the consequences of interfering with FoxP3 gene in human GC cell lines, AGS and MKN45, by multiple cellular and molecular approaches, such as immunofluorescence, gene transfection, CCK-8 assay, clone formation assay, TUNEL assay, Flow cytometry, immunoassay and quantities polymerase chain reaction (PCR). As a result, FoxP3 was expressed both in nucleus and cytoplasm of GC cells. Up-regulation of FoxP3 inhibited cell proliferation and promoted cell apoptosis. Overexpression of FoxP3 increased the protein and mRNA levels of proapoptotic molecules, such as poly ADP-ribose polymerase1 (PARP), caspase-3 and caspase-9, and repressed the expression of antiapoptotic molecules, such as cellular inhibitor of apoptosis-1 (c-IAP1) and the long isoform of B cell leukemia/lymphoma-2 (Bcl-2). Furthermore, silencing of FoxP3 by siRNA in GC cells reduced the expression of proapoptotic genes, such as PARP, caspase-3 and caspase-9. Collectively, our findings identify the novel roles of FoxP3 in inhibiting proliferation and inducing apoptosis

  3. A contribution to the deterministic modelling of circadian rhythms in cell proliferation activity

    OpenAIRE

    Nieto, M; Álvarez Cabal, Ramón; Hacar Benítez, Miguel Ángel; Alarcón Álvarez, Enrique

    1987-01-01

    This paper presents a deterministic continuous model of proliferative cell activity. The classical series of connected compartments is revisited along with a simple mathematical treatment of two hypotheses: constant transit times and harmonic Ts. Several examples are presented to support these ideas, both taken from previous literature and recent experiences with the fish Carassius auratus, developed at the Junta de Energía Nuclear, Madrid, Spain.

  4. BRAF activated non-coding RNA (BANCR) promoting gastric cancer cells proliferation via regulation of NF-κB1

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Zhi-Xin; Liu, Zhi-Qiang; Jiang, Biao; Lu, Xin-Yang; Ning, Xiao-Fei [Department of Gastrointestinal Surgery, Affiliated Hospital of Jining Medical University, Jining 272029 (China); Yuan, Chuan-Tao [Department of Pathology, Affiliated Hospital of Jining Medical University, Jining 272029 (China); Wang, Ai-Liang, E-mail: wang_ailiang@126.com [Department of Gastrointestinal Surgery, Affiliated Hospital of Jining Medical University, Jining 272029 (China)

    2015-09-18

    Background and objective: Long non-coding RNA, BANCR, has been demonstrated to contribute to the proliferation and migration of tumors. However, its molecular mechanism underlying gastric cancer is still unknown. In present study, we investigated whether BANCR was involved in the development of gastric cancer cells via regulation of NF-κB1. Methods: Human gastric cancer tissues were isolated as well as human gastric cell lines MGC803 and BGC823 were cultured to investigate the role of BANCR in gastric cancer. Results: BANCR expression was significantly up-regulated in gastric tumor tissues and gastric cell lines. Down-regulation of BANCR inhibited gastric cancer cell growth and promoted cell apoptosis, and it also contributed to a significant decrease of NF-κB1 (P50/105) expression and 3′UTR of NF-κB1 activity. Overexpression of NF-κB1 reversed the effect of BANCR on cancer cell growth and apoptosis. MiroRNA-9 (miR-9) targeted NF-κB1, and miR-9 inhibitor also reversed the effects of BANCR on gastric cancer cell growth and apoptosis. Conclusion: BANCR was highly expressed both in gastric tumor tissues and in cancer cells. NF-κB1 and miR-9 were involved in the role of BANCR in gastric cancer cell growth and apoptosis. - Highlights: • BANCR up-regulated in gastric cancer (GC) tissues and cell lines MGC803 and BGC823. • Down-regulation of BANCR inhibited GC cell growth and promoted cell apoptosis. • Down-regulation of BANCR contributed to decreased 3′UTR of NF-κB1 and its expression. • Overexpressed NF-κB1 reversed the effect of BANCR on GC cell growth. • miR-9 inhibitor reversed the effect of BANCR on cancer GC cell growth.

  5. Regulatory activity of azabisphosphonate-capped dendrimers on human CD4+ T cell proliferation enhances ex-vivo expansion of NK cells from PBMCs for immunotherapy

    Directory of Open Access Journals (Sweden)

    Caminade Anne-Marie

    2009-09-01

    Full Text Available Abstract Background Adoptive cell therapy with allogenic NK cells constitutes a promising approach for the treatment of certain malignancies. Such strategies are currently limited by the requirement of an efficient protocol for NK cell expansion. We have developed a method using synthetic nanosized phosphonate-capped dendrimers allowing such expansion. We are showing here that this is due to a specific inhibitory activity towards CD4+ T cell which could lead to further medical applications of this dendrimer. Methods Mononuclear cells from human peripheral blood were used to investigate the immunomodulatory effects of nanosized phosphonate-capped dendrimers on interleukin-2 driven CD4+T cell expansion. Proliferation status was investigated using flow cytometry analysis of CFSE dilution and PI incorporation experiments. Magnetic bead cell sorting was used to address activity towards individual or mixed cell sub-populations. We performed equilibrium binding assay to assess the interaction of fluorescent dendrimers with pure CD4+ T cells. Results Phosphonate-capped dendrimers are inhibiting the activation, and therefore the proliferation; of CD4+ T cells in IL-2 stimulated PBMCs, without affecting their viability. This allows a rapid enrichment of NK cells and further expansion. We found that dendrimer acts directly on T cells, as their regulatory property is maintained when stimulating purified CD4+ T cells with anti-CD3/CD28 microbeads. Performing equilibrium binding assays using a fluorescent analogue, we show that the phosphonate capped-dendrimers are specifically interacting with purified CD4+ T cells. Ultimately, we found that our protocol prevents the IL-2 related expansion of regulatory T cells that would be deleterious for the activity of infused NK cells. Conclusion High yield expansion of NK cells from human PBMCs by phosphonate-capped dendrimers and IL-2 occurs through the specific inhibition of the CD4+ lymphocyte compartment. Given the

  6. Secreted Stress-Induced Phosphoprotein 1 Activates the ALK2-SMAD Signaling Pathways and Promotes Cell Proliferation of Ovarian Cancer Cells

    Directory of Open Access Journals (Sweden)

    Chia-Lung Tsai

    2012-08-01

    Full Text Available Stress-induced phosphoprotein 1 (STIP1, a cochaperone that organizes other chaperones, heat shock proteins (HSPs, was recently shown to be secreted by human ovarian cancer cells. In neuronal tissues, binding to prion protein was required for STIP1 to activate the ERK (extracellular-regulated MAP kinase signaling pathways. However, we report that STIP1 binding to a bone morphogenetic protein (BMP receptor, ALK2 (activin A receptor, type II-like kinase 2, was necessary and sufficient to stimulate proliferation of ovarian cancer cells. The binding of STIP1 to ALK2 activated the SMAD signaling pathway, leading to transcriptional activation of ID3 (inhibitor of DNA binding 3, promoting cell proliferation. In conclusion, ovarian-cancer-tissue-secreted STIP1 stimulates cancer cell proliferation by binding to ALK2 and activating the SMAD-ID3 signaling pathways. Although animal studies are needed to confirm these mechanisms in vivo, our results may pave the way for developing novel therapeutic strategies for ovarian cancer.

  7. Mesenchymal stem cells suppress fibroblast proliferation and reduce skin fibrosis through a TGF-β3-dependent activation.

    Science.gov (United States)

    Wu, Yan; Peng, Yan; Gao, Dongyun; Feng, Changjiang; Yuan, Xiaohuan; Li, Houzhong; Wang, Ying; Yang, Lan; Huang, Sha; Fu, Xiaobing

    2015-03-01

    Recent studies showed that transplantation of mesenchymal stem cells (MSCs) significantly decreased tissue fibrosis; however, little attention has been paid to its efficacy on attenuating skin fibrosis, and the mechanism involved in its effect is poorly understood. In this work, we investigated the effects of MSCs on keloid fibroblasts and extracellular matrix deposition through paracrine actions and whether the antifibrotic properties of MSCs involved transforming growth factor-β (TGF-β)-dependent activation. In vitro experiments showed that conditioned media (CM) from MSCs decreased viability, a-smooth muscle actin expression, and collagen secretion of human keloid fibroblasts. In addition, TGF-β3 secreted by MSCs was expressed at high level under inflammatory environment, and blocking the activity of TGF-β3 apparently antagonized the suppressive activity of MSC CM, which demonstrated that TGF-β3 played a preponderant role in preventing collagen accumulation. In vivo studies showed that MSC CM infusion in a mouse dermal fibrosis model induced a significant decrease in skin fibrosis. Histological examination of tissue sections and immunohistochemical analysis for α-smooth muscle actin revealed that TGF-β3 of CM-mediated therapeutic effects could obviously attenuate matrix production and myofibroblast proliferation and differentiation. These findings suggest that TGF-β3 mediates the attenuating effect of MSCs on both the proliferation and extracellular matrix production of human keloid fibroblasts and decreases skin fibrosis of mouse model, thus providing new understanding and MSC-based therapeutic strategy for cutaneous scar treatment.

  8. Activation of CD1d-restricted natural killer T cells can inhibit cancer cell proliferation during chemotherapy by promoting the immune responses in murine mesothelioma.

    Science.gov (United States)

    Wu, Licun; Yun, Zhihong; Tagawa, Tetsuzo; De la Maza, Luis; Wu, Matthew Onn; Yu, Julie; Zhao, Yidan; de Perrot, Marc

    2014-12-01

    We studied the impact of natural killer T (NKT) cell activation by alpha-galactocysylceramide (α-GalCer, α-GC) on cancer cell repopulation during chemotherapy in murine mesothelioma. The number of NKT cells was found to be increased during the development of murine mesothelioma. NKT cells specifically recognize α-GC through CD1d resulting in their activation and expansion. Tumor-bearing mice were treated with chemotherapy once weekly, and α-GC was followed after each cycle of chemotherapy. Anti-tumor effect was evaluated on wild-type (WT) and CD1d knockout (CD1dKO) mice. Cancer cell proliferation and apoptosis were evaluated by Ki67 and TUNEL immunohistochemistry. CD4(+) and CD8(+) T cell proportion and activation in tumor, spleen, draining lymph node and peripheral blood were determined by flow cytometry, and gene expression of activated T cell-related cytokines was quantified by reverse transcription PCR. NKT cells were identified by CD1d-α-GC-tetramer staining. In WT mice, tumor growth delay was achieved by cisplatin (Cis), and this effect was improved in combination with α-GC, but α-GC alone had little effect. Cancer cell proliferation during chemotherapy was significantly inhibited by α-GC, while cancer cell death was significantly upregulated. α-GC following chemotherapy resulted in NKT cell expansion and an increase of interferon-γ production in the draining lymph node, blood and spleen. Gene expression of immune-associated cytokines was upregulated. Strikingly, the percentage of inducible T cell co-stimulator(+)CD4 T cells, Th17/Tc17 cells increased in splenocytes. In CD1d KO mice, however, Cis alone was less effective and Cis + α-GC provided no additional benefit over Cis alone. α-GC alone had minimal effect in both mice. NKT activation between cycles of chemotherapy could improve the outcome of mesothelioma treatment. PMID:25183171

  9. Laminin isoforms differentially regulate adhesion, spreading, proliferation, and ERK activation of β1 integrin-null cells

    International Nuclear Information System (INIS)

    The presence of many laminin receptors of the β1 integrin family on most cells makes it difficult to define the biological functions of other major laminin receptors such as integrin α6β4 and dystroglycan. We therefore tested the binding of a β1 integrin-null cell line GD25 to four different laminin variants. The cells were shown to produce dystroglycan, which based on affinity chromatography bound to laminin-1, -2/4, and -10/11, but not to laminin-5. The cells also expressed the integrin α6Aβ4A variant. GD25 β1 integrin-null cells are known to bind poorly to laminin-1, but we demonstrate here that these cells bind avidly to laminin-2/4, -5, and -10/11. The initial binding at 20 min to each of these laminins could be inhibited by an integrin α6 antibody, but not by a dystroglycan antibody. Hence, integrin α6Aβ4A of GD25 cells was identified as a major receptor for initial GD25 cell adhesion to three out of four tested laminin isoforms. Remarkably, cell adhesion to laminin-5 failed to promote cell spreading, proliferation, and extracellular signal-regulated kinase (ERK) activation, whereas all these responses occurred in response to adhesion to laminin-2/4 or -10/11. The data establish GD25 cells as useful tools to define the role integrin α6Aβ4A and suggest that laminin isoforms have distinctly different capacities to promote cell adhesion and signaling via integrin α6Aβ4A

  10. Dact2 represses PITX2 transcriptional activation and cell proliferation through Wnt/beta-catenin signaling during odontogenesis.

    Directory of Open Access Journals (Sweden)

    Xiao Li

    Full Text Available Dact proteins belong to the Dapper/Frodo protein family and function as cytoplasmic attenuators in Wnt and TGFβ signaling. Previous studies show that Dact1 is a potent Wnt signaling inhibitor by promoting degradation of β-catenin. We report a new mechanism for Dact2 function as an inhibitor of the canonical Wnt signaling pathway by interacting with PITX2. PITX2 is a downstream transcription factor in Wnt/β-catenin signaling, and PITX2 synergizes with Lef-1 to activate downstream genes. Immunohistochemistry verified the expression of Dact2 in the tooth epithelium, which correlated with Pitx2 epithelial expression. Dact2 loss of function and PITX2 gain of function studies reveal a feedback mechanism for controlling Dact2 expression. Pitx2 endogenously activates Dact2 expression and Dact2 feeds back to repress Pitx2 transcriptional activity. A Topflash reporter system was employed showing PITX2 activation of Wnt signaling, which is attenuated by Dact2. Transient transfections demonstrate the inhibitory effect of Dact2 on critical dental epithelial differentiation factors during tooth development. Dact2 significantly inhibits PITX2 activation of the Dlx2 and amelogenin promoters. Multiple lines of evidence conclude the inhibition is achieved by the physical interaction between Dact2 and Pitx2 proteins. The loss of function of Dact2 also reveals increased cell proliferation due to up-regulated Wnt downstream genes, cyclinD1 and cyclinD2. In summary, we have identified a novel role for Dact2 as an inhibitor of the canonical Wnt pathway in embryonic tooth development through its regulation of cell proliferation and differentiation.

  11. SGLT1 activity in lung alveolar cells of diabetic rats modulates airway surface liquid glucose concentration and bacterial proliferation

    OpenAIRE

    Tales Lyra Oliveira; Návylla Candeia-Medeiros; Polliane M. Cavalcante-Araújo; Igor Santana Melo; Elaine Fávaro-Pípi; Luciana Alves Fátima; Antônio Augusto Rocha; Luiz Ricardo Goulart; Ubiratan Fabres Machado; Ruy R. Campos; Robinson Sabino-Silva

    2016-01-01

    High glucose concentration in the airway surface liquid (ASL) is an important feature of diabetes that predisposes to respiratory infections. We investigated the role of alveolar epithelial SGLT1 activity on ASL glucose concentration and bacterial proliferation. Non-diabetic and diabetic rats were intranasally treated with saline, isoproterenol (to increase SGLT1 activity) or phlorizin (to decrease SGLT1 activity); 2 hours later, glucose concentration and bacterial proliferation (methicillin-...

  12. SGLT1 activity in lung alveolar cells of diabetic rats modulates airway surface liquid glucose concentration and bacterial proliferation

    Science.gov (United States)

    Oliveira, Tales Lyra; Candeia-Medeiros, Návylla; Cavalcante-Araújo, Polliane M.; Melo, Igor Santana; Fávaro-Pípi, Elaine; Fátima, Luciana Alves; Rocha, Antônio Augusto; Goulart, Luiz Ricardo; Machado, Ubiratan Fabres; Campos, Ruy R.; Sabino-Silva, Robinson

    2016-01-01

    High glucose concentration in the airway surface liquid (ASL) is an important feature of diabetes that predisposes to respiratory infections. We investigated the role of alveolar epithelial SGLT1 activity on ASL glucose concentration and bacterial proliferation. Non-diabetic and diabetic rats were intranasally treated with saline, isoproterenol (to increase SGLT1 activity) or phlorizin (to decrease SGLT1 activity); 2 hours later, glucose concentration and bacterial proliferation (methicillin-resistant Sthaphylococcus aureus, MRSA and Pseudomonas aeruginosa, P. aeruginosa) were analyzed in bronchoalveolar lavage (BAL); and alveolar SGLT1 was analyzed by immunohistochemistry. BAL glucose concentration and bacterial proliferation increased in diabetic animals: isoproterenol stimulated SGLT1 migration to luminal membrane, and reduced (50%) the BAL glucose concentration; whereas phlorizin increased the BAL glucose concentration (100%). These regulations were accompanied by parallel changes of in vitro MRSA and P. aeruginosa proliferation in BAL (r = 0.9651 and r = 0.9613, respectively, Pearson correlation). The same regulations were observed in in vivo P. aeruginosa proliferation. In summary, the results indicate a relationship among SGLT1 activity, ASL glucose concentration and pulmonary bacterial proliferation. Besides, the study highlights that, in situations of pulmonary infection risk, such as in diabetic subjects, increased SGLT1 activity may prevent bacterial proliferation whereas decreased SGLT1 activity can exacerbate it. PMID:26902517

  13. Early peroxisome proliferator-activated receptor gamma regulated genes involved in expansion of pancreatic beta cell mass

    Directory of Open Access Journals (Sweden)

    Vivas Yurena

    2011-12-01

    Full Text Available Abstract Background The progression towards type 2 diabetes depends on the allostatic response of pancreatic beta cells to synthesise and secrete enough insulin to compensate for insulin resistance. The endocrine pancreas is a plastic tissue able to expand or regress in response to the requirements imposed by physiological and pathophysiological states associated to insulin resistance such as pregnancy, obesity or ageing, but the mechanisms mediating beta cell mass expansion in these scenarios are not well defined. We have recently shown that ob/ob mice with genetic ablation of PPARγ2, a mouse model known as the POKO mouse failed to expand its beta cell mass. This phenotype contrasted with the appropriate expansion of the beta cell mass observed in their obese littermate ob/ob mice. Thus, comparison of these models islets particularly at early ages could provide some new insights on early PPARγ dependent transcriptional responses involved in the process of beta cell mass expansion Results Here we have investigated PPARγ dependent transcriptional responses occurring during the early stages of beta cell adaptation to insulin resistance in wild type, ob/ob, PPARγ2 KO and POKO mice. We have identified genes known to regulate both the rate of proliferation and the survival signals of beta cells. Moreover we have also identified new pathways induced in ob/ob islets that remained unchanged in POKO islets, suggesting an important role for PPARγ in maintenance/activation of mechanisms essential for the continued function of the beta cell. Conclusions Our data suggest that the expansion of beta cell mass observed in ob/ob islets is associated with the activation of an immune response that fails to occur in POKO islets. We have also indentified other PPARγ dependent differentially regulated pathways including cholesterol biosynthesis, apoptosis through TGF-β signaling and decreased oxidative phosphorylation.

  14. Lipid nanocarriers based on natural oils with high activity against oxygen free radicals and tumor cell proliferation.

    Science.gov (United States)

    Lacatusu, I; Badea, N; Badea, G; Oprea, O; Mihaila, M A; Kaya, D A; Stan, R; Meghea, A

    2015-11-01

    The development of nano-dosage forms of phytochemicals represents a significant progress of the scientific approach in the biomedical research. The aim of this study was to assess the effectiveness of lipid nanocarriers based on natural oils (grape seed oil, fish oil and laurel leaf oil) in counteracting free radicals and combating certain tumor cells. No drug was encapsulated in the nanocarriers. The cytotoxic effect exerted by bioactive nanocarriers against two tumor cells, MDA-MB 231 and HeLa cell lines, and two normal cells, L929 and B16 cell lines, was measured using the MTT assay, while oxidative damage was assessed by measuring the total antioxidant activity using chemiluminescence analysis. The best performance was obtained for nanocarriers based on an association of grape seed and laurel leaf oils, with a capacity to scavenge about 98% oxygen free radicals. A dose of nanocarriers of 5mg·mL(-1) has led to a drastic decrease in tumor cell proliferation even in the absence of an antitumor drug (e.g. about 50% viability for MDA-MB 231 cell line and 60% viability for HeLa cell line). A comparative survival profile of normal and tumor cells, which were exposed to an effective dose of 2.5mg·mL(-1) lipid nanocarriers, has revealed a death rate of 20% for normal B16 cells and of 40% death rate for MDA-MB 231 and HeLa tumor cells. The results in this study imply that lipid nanocarriers based on grape seed oil in association with laurel leaf oil could be a candidate to reduce the delivery system toxicity and may significantly improve the therapeutic efficacy of antitumor drugs in clinical applications.

  15. Increase in intracellular calcium and activation of protein kinase C in the expression of lymphokine receptors and the proliferation of murine B-cells

    Energy Technology Data Exchange (ETDEWEB)

    Proust, J.; Filburn, C.; Chrest, F.; Buchholz, M.; Nordin, A.

    1986-03-01

    BCGF dependent B cell proliferation requires costimulation by anti-..mu.. whereas IL2 dependent B cell proliferation requires preactivation by both anti-..mu.. and LPS. These studies show that in the BCGF dependent pathway the activation signal delivered by anti-..mu.. can be mimicked by an increase in intracellular calcium ((Ca/sup 2 +/)i) induced by the calcium ionophore, Ionomycin. In the IL2 dependent pathway, the additional signal delivered by LPS that leads to IL2 receptors expression and cell proliferation, can be replaced by the phorbol ester PMA as well as the diacylglycerol sn-1,2-dioctanoyl glycerol (DiC8), both shown to induce protein kinase C (PKc) activation. In agreement with these observations they show that LPS activates PKc with no concomitant increase in intracellular calcium ((Ca/sup 2 +/)i), while anti-..mu.. induces an increase in (Ca/sup 2 +/)i but no PKc activation. (Ca/sup 2 +/)i increase and PKc activation are both critical for the expression of IL2 receptor and the subsequent IL2 proliferation whereas an increase in (Ca/sup 2 +/)i is sufficient to induce BCGF dependent proliferation. These results suggest that the activation signals leading to BCGF and IL2 dependent proliferation proceed through 2 different biochemical pathways.

  16. Protease-activated receptor-1 negatively regulates proliferation of neural stem/progenitor cells derived from the hippocampal dentate gyrus of the adult mouse.

    Science.gov (United States)

    Tanaka, Masayuki; Yoneyama, Masanori; Shiba, Tatsuo; Yamaguchi, Taro; Ogita, Kiyokazu

    2016-07-01

    Thrombin-activated protease-activated receptor (PAR)-1 regulates the proliferation of neural cells following brain injury. To elucidate the involvement of PAR-1 in the neurogenesis that occurs in the adult hippocampus, we examined whether PAR-1 regulated the proliferation of neural stem/progenitor cells (NPCs) derived from the murine hippocampal dentate gyrus. NPC cultures expressed PAR-1 protein and mRNA encoding all subtypes of PAR. Direct exposure of the cells to thrombin dramatically attenuated the cell proliferation without causing cell damage. This thrombin-induced attenuation was almost completely abolished by the PAR antagonist RWJ 56110, as well as by dabigatran and 4-(2-aminoethyl)benzenesulfonyl fluoride (AEBSF), which are selective and non-selective thrombin inhibitors, respectively. Expectedly, the PAR-1 agonist peptide (AP) SFLLR-NH2 also attenuated the cell proliferation. The cell proliferation was not affected by the PAR-1 negative control peptide RLLFT-NH2, which is an inactive peptide for PAR-1. Independently, we determined the effect of in vivo treatment with AEBSF or AP on hippocampal neurogenesis in the adult mouse. The administration of AEBSF, but not that of AP, significantly increased the number of newly-generated cells in the hippocampal subgranular zone. These data suggest that PAR-1 negatively regulated adult neurogenesis in the hippocampus by inhibiting the proliferative activity of the NPCs. PMID:27426918

  17. Blue light inhibits proliferation of melanoma cells

    Science.gov (United States)

    Becker, Anja; Distler, Elisabeth; Klapczynski, Anna; Arpino, Fabiola; Kuch, Natalia; Simon-Keller, Katja; Sticht, Carsten; van Abeelen, Frank A.; Gretz, Norbert; Oversluizen, Gerrit

    2016-03-01

    Photobiomodulation with blue light is used for several treatment paradigms such as neonatal jaundice, psoriasis and back pain. However, little is known about possible side effects concerning melanoma cells in the skin. The aim of this study was to assess the safety of blue LED irradiation with respect to proliferation of melanoma cells. For that purpose we used the human malignant melanoma cell line SK-MEL28. Cell proliferation was decreased in blue light irradiated cells where the effect size depended on light irradiation dosage. Furthermore, with a repeated irradiation of the melanoma cells on two consecutive days the effect could be intensified. Fluorescence-activated cell sorting with Annexin V and Propidium iodide labeling did not show a higher number of dead cells after blue light irradiation compared to non-irradiated cells. Gene expression analysis revealed down-regulated genes in pathways connected to anti-inflammatory response, like B cell signaling and phagosome. Most prominent pathways with up-regulation of genes were cytochrome P450, steroid hormone biosynthesis. Furthermore, even though cells showed a decrease in proliferation, genes connected to the cell cycle were up-regulated after 24h. This result is concordant with XTT test 48h after irradiation, where irradiated cells showed the same proliferation as the no light negative control. In summary, proliferation of melanoma cells can be decreased using blue light irradiation. Nevertheless, the gene expression analysis has to be further evaluated and more studies, such as in-vivo experiments, are warranted to further assess the safety of blue light treatment.

  18. ERK-dependent activation of Sp1 is required for low-power laser irradiation-induced vascular endothelial cell proliferation

    Science.gov (United States)

    Feng, Jie; Xing, Da

    2012-12-01

    Here, we report that low-power laser irradiation (LPLI) activates ERK/Sp1 pathway to upregulate VEGF expression and promote vascular endothelial cell proliferation. We demonstrate for the first time that LPLI enhances DNA-binding activity and transactivation activity of Sp1 on VEGF promoter. Additionally, ERK translocates from cytoplasm to nucleus following LPLI. Moreover, activated ERK phosphorylates Sp1 and results in increased EKR-Sp1 interaction. Selective inhibition of Sp1 or ERK suppresses the effect of LPLI on the promotion of cell cycle progression and proliferation. These findings provide a novel link between LPLI and angiogenesis, supplying potential therapy strategies for angiogenesis with LPLI.

  19. Effects of curcumin on peroxisome proliferator-activated receptor γ expression and nuclear translocation/redistribution in culture-activated rat hepatic stellate cells

    Institute of Scientific and Technical Information of China (English)

    CHENG Yang; PING Jian; XU Lie-ming

    2007-01-01

    Background The function of peroxisome proliferator-activated receptor γ (PPARγ) in hepatic fibrogenesis remains largely unknown. Curcumin is a natural substance extracted form Curcuma Longa Linn and has a variety of pharmacological effects. In this study, the effects of curcumin on the proliferation, activation and apoptosis of rat hepatic stellate cells (HSCs) through PPARγ signaling were investigated.Methods HSCs were isolated from the normal Sprague Dawley rats through in situ perfusion of the liver with Pronase E and density-gradient centrifugation with Nycodenz. Cells were treated with curcumin, troglitazone, salvianolic acid B or GW9662. The effect on HSCs proliferation was determined by MTT colorimetry. Total RNA was extracted by TRizol reagent and gene levels were determined by semi-quantitative RT-PCR. Total cellular and nuclear protein were isolated and separated by 10% sodium dodecy Isulfate polyacrylamide gel electrophoresis. Protein levels were determined by Western blot. Cell apoptosis was detected by Hoechst 33258 staining. PPARγ subcellular distribution was detected by immunofluorescent staining. The activities of MMP-2 and 9 were measured by Gelatin zymograph assay.Results Curcumin suppressed HSCs proliferation in a dose-dependent manner. As HSCs underwent gradual activation with culture prolongation the PPARγ nuclear expression level decreased. Curcumin up-regulated PPARγ expression and significantly inhibited the production of α-SMA and collagen I. PPARγ is expressed in the cytoplasm and nucleus and is evenly distributed in HSCs, but accumulated in the nucleus of HSCs and disappeared from cytoplasm after curcumin treatment. Hoechst 33258 staining showed that curcumin induced the apoptosis of culture-activated HSCs and significantly increased pro-apoptotic Bax expression and reduced anti-apoptotic Bcl-2 expression. Cyclin D1 gene, activated NFκB p65 protein and TGFβR-I protein expression were down-regulated significantly by curcumin. The

  20. The glucagon-like peptide 1 receptor agonist enhances intrinsic peroxisome proliferator-activated receptor γ activity in endothelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Onuma, Hirohisa; Inukai, Kouichi, E-mail: kinukai@ks.kyorin-u.ac.jp; Kitahara, Atsuko; Moriya, Rie; Nishida, Susumu; Tanaka, Toshiaki; Katsuta, Hidenori; Takahashi, Kazuto; Sumitani, Yoshikazu; Hosaka, Toshio; Ishida, Hitoshi

    2014-08-22

    Highlights: • PPARγ activation was involved in the GLP-1-mediated anti-inflammatory action. • Exendin-4 enhanced endogenous PPARγ transcriptional activity in HUVECs. • H89, a PKA inhibitor, abolished GLP-1-induced PPARγ enhancement. • The anti-inflammatory effects of GLP-1 may be explained by PPARγ activation. - Abstract: Recent studies have suggested glucagon-like peptide-1 (GLP-1) signaling to exert anti-inflammatory effects on endothelial cells, although the precise underlying mechanism remains to be elucidated. In the present study, we investigated whether PPARγ activation is involved in the GLP-1-mediated anti-inflammatory action on endothelial cells. When we treated HUVEC cells with 0.2 ng/ml exendin-4, a GLP-1 receptor agonist, endogenous PPARγ transcriptional activity was significantly elevated, by approximately 20%, as compared with control cells. The maximum PPARγ activity enhancing effect of exendin-4 was observed 12 h after the initiation of incubation with exendin-4. As H89, a PKA inhibitor, abolished GLP-1-induced PPARγ enhancement, the signaling downstream from GLP-1 cross-talk must have been involved in PPARγ activation. In conclusion, our results suggest that GLP-1 has the potential to induce PPARγ activity, partially explaining the anti-inflammatory effects of GLP-1 on endothelial cells. Cross-talk between GLP-1 signaling and PPARγ activation would have major impacts on treatments for patients at high risk for cardiovascular disease.

  1. Stimulation of cell proliferation by glutathione monoethyl ester in aged bone marrow stromal cells is associated with the assistance of TERT gene expression and telomerase activity.

    Science.gov (United States)

    Aminizadeh, Najmeh; Tiraihi, Taki; Mesbah-Namin, Seyed Alireza; Taheri, Taher

    2016-08-01

    The proliferation and differentiation potential of aged bone marrow stromal cells (BMSCs) are significantly reduced. In order to improve the performance of the aged BMSCs, these cells were treated with 2 mM glutathione monoethyl ester (GSH-MEE) for 24 h. Proliferation rate, telomerase activity, telomere length, and differentiation to cholinergic neuron-like cells (CNLCs) were observed to increase. Though, the expression level of telomerase reverse transcriptase gene increased, but CTC1 and TEN1 genes from Ctc1-Stn1-Ten1 complex encoding proteins with regulatory function significantly decreased. Trypan blue exclusion assay was used to analyze the proliferation and, while telomere length, its several related gene expressions, and telomerase activity were measured using the real time reverse transcription-polymerase chain reaction and polymerase chain reaction enzyme-linked immunosorbent assay techniques, respectively. CNLCs differentiation potential was evaluated by estimating the percentage of choline acetyltransferase immunereactive cells.The results suggested that GSH-MEE could improve aged rat BMSC properties and would be of potential benefit for enhancing the performance of aged people's BMSCs. PMID:27251157

  2. Hepatocyte growth factor activator inhibitor-1 is induced by bone morphogenetic proteins and regulates proliferation and cell fate of neural progenitor cells.

    Directory of Open Access Journals (Sweden)

    Raili Koivuniemi

    Full Text Available BACKGROUND: Neural progenitor cells (NPCs in the developing neuroepithelium are regulated by intrinsic and extrinsic factors. There is evidence that NPCs form a self-supporting niche for cell maintenance and proliferation. However, molecular interactions and cell-cell contacts and the microenvironment within the neuroepithelium are largely unknown. We hypothesized that cellular proteases especially those associated with the cell surface of NPCs play a role in regulation of progenitor cells in the brain. METHODOLOGY/PRINCIPAL FINDINGS: In this work, we show that NPCs, isolated from striatal anlage of developing rat brain, express hepatocyte growth factor activator inhibitor-1 and -2 (HAI-1 and HAI-2 that are cell surface-linked serine protease inhibitors. In addition, radial glia cells derived from mouse embryonic stem cells also express HAI-1 and HAI-2. To study the functional significance of HAI-1 and HAI-2 in progenitor cells, we modulated their levels using expression plasmids or silencing RNA (siRNA transfected into the NPCs. Data showed that overexpression of HAI-1 or HAI-2 decreased cell proliferation of cultured NPCs, whilst their siRNAs had opposite effects. HAI-1 also influenced NPC differentiation by increasing the number of glial fibrillary acidic protein (GFAP expressing cells in the culture. Expression of HAI-1 in vivo decreased cell proliferation in developing neuroepithelium in E15 old animals and promoted astrocyte cell differentiation in neonatal animals. Studying the regulation of HAI-1, we observed that Bone morphogenetic protein-2 (BMP-2 and BMP-4 increased HAI-1 levels in the NPCs. Experiments using HAI-1-siRNA showed that these BMPs act on the NPCs partly in a HAI-1-dependent manner. CONCLUSIONS: This study shows that the cell-surface serine protease inhibitors, HAI-1 and HAI-2 influence proliferation and cell fate of NPCs and their expression levels are linked to BMP signaling. Modulation of the levels and actions of HAI-1

  3. Dual regulatory effects of resveratrol on activation of NF-κB and cell proliferation in human embryonal kidney 293 cells

    Institute of Scientific and Technical Information of China (English)

    YIN Hong; CHENG Guifang

    2005-01-01

    Resveratrol (3,4′,5-trihydroxystilbene, Res), a naturally occurring polyphenol, exhibits antioxidant, anti- inflammatory, potential chemopreventive and chemotherapeutic properties in preclinical studies. To further understand its potential clinical efficacy and safety, effect of Res at 10-9―10-4 mol/L on human embryonal kidney (HEK293) cell proliferation and its potential mechanism were investigated in present study. Cell viability was detected by using trypan blue dye exclusion method. Cell cycle and apoptosis were analyzed by flow cytometry with propidium iodide stain. Activation of nuclear factor-κB (NF-κB) was determined by luciferase reporter gene assay using stably transfected HEK293/κB-luc cells. Secretion of human interleukin-8 (hIL-8) was measured by ELISA. Our results show that HEK293 cell proliferation was significantly stimulated by 10-7 mol/L Res after treatment for 48 hours, or by 10-8―10-7 mol/L Res combinated with 10 ng/mL TNFα for 24 h, but was suppressed by 10-4 mol/L Res with or without TNFα. Both endogenous and TNFα-induced NF-κB activation were downregulated by Res at 10-7 mol/L, but were upregulated at 10-4 mol/L. With 10-4 mol/L Res, the content of secreted IL-8 was increased, and apoptosis rate was increased from less than 5% to 10%, together with significant cell-cycle arrest in S phase. TNFα has coordinative effects with Res on HEK293 cell apoptosis, cell-cycle arrest and IL-8 secretion. These results indicate that Res promotes cell proliferation at low concentration through down-regulation of NF-κB activation in HEK293, but suppresses its growth at high concentration through up-regulation of NF-κB activation, increasing IL-8 and cell-cycle arrest. As resveratrol has dual regulatory effect on cell proliferation in vitro, comprehensive evaluation of its potential clinical utility is needed.

  4. Contribution of phospholipase D in endothelin-1-mediated extracellular signal-regulated kinase activation and proliferation in rat uterine leiomyoma cells.

    Science.gov (United States)

    Robin, Philippe; Chouayekh, Sondes; Bole-Feysot, Christine; Leiber, Denis; Tanfin, Zahra

    2005-01-01

    Endothelin (ET)-1 is a mitogenic factor in numerous cell types, including rat myometrial cells. In the present study, we investigated the potential role of ET-1 in the proliferation of tumoral uterine smooth muscle cells (ELT-3 cells). We found that ET-1 exerted a more potent mitogenic effect in ELT-3 cells than in normal myometrial cells, as indicated by the increase in [3H]thymidine incorporation, cell number, and bromodeoxyuridine incorporation. The ET-1 was more efficient than platelet-derived growth factor and epidermal growth factor to stimulate proliferation. The ET-1-mediated cell proliferation was inhibited in the presence of U0126, a specific inhibitor of (mitogen-activated protein kinase ERK kinase), indicating that extracellular signal-regulated kinase (ERK) activation is involved. Additionally, ET-1 induced the activation of phospholipase (PL) D, leading to the synthesis of phosphatidic acid (PA). The ET-1-induced activation of PLD was twofold higher in ELT-3 cells compared to that in normal cells. The two cell types expressed mRNA for PLD1a and PLD2, whereas PLD1b was expressed only in ELT-3 cells. The exposure of cells to butan-1-ol reduced ET-1-mediated production of PA by PLD and partially inhibited ERK activation and DNA synthesis. Addition of exogenous PLD or PA in the medium reproduced the effect of ET-1 on ERK activation and cell proliferation. Collectively, these data indicate that ET-1 is a potent mitogenic factor in ELT-3 cells via a signaling pathway involving a PLD-dependent activation of ERK. This highlights the potential role of ET-1 in the development of uterine leiomyoma, and it reinforces the role of PLD in tumor growth. PMID:15355882

  5. Lipid nanocarriers based on natural oils with high activity against oxygen free radicals and tumor cell proliferation

    Energy Technology Data Exchange (ETDEWEB)

    Lacatusu, I.; Badea, N.; Badea, G.; Oprea, O. [University Politehnica of Bucharest, Faculty of Applied Chemistry and Materials Science, Polizu Street No 1, 011061 Bucharest (Romania); Mihaila, M.A. [Institute of Virusology “Stefan S. Nicolau”, Center of Immunology, Bravu Road, No. 285, 030304 Bucharest (Romania); Kaya, D.A. [Department of Field Crops, Faculty of Agriculture, Mustafa Kemal University, 31030 Antakya, Hatay (Turkey); Stan, R., E-mail: rl_stan2000@yahoo.com [University Politehnica of Bucharest, Faculty of Applied Chemistry and Materials Science, Polizu Street No 1, 011061 Bucharest (Romania); Meghea, A. [University Politehnica of Bucharest, Faculty of Applied Chemistry and Materials Science, Polizu Street No 1, 011061 Bucharest (Romania)

    2015-11-01

    The development of nano-dosage forms of phytochemicals represents a significant progress of the scientific approach in the biomedical research. The aim of this study was to assess the effectiveness of lipid nanocarriers based on natural oils (grape seed oil, fish oil and laurel leaf oil) in counteracting free radicals and combating certain tumor cells. No drug was encapsulated in the nanocarriers. The cytotoxic effect exerted by bioactive nanocarriers against two tumor cells, MDA-MB 231 and HeLa cell lines, and two normal cells, L929 and B16 cell lines, was measured using the MTT assay, while oxidative damage was assessed by measuring the total antioxidant activity using chemiluminescence analysis. The best performance was obtained for nanocarriers based on an association of grape seed and laurel leaf oils, with a capacity to scavenge about 98% oxygen free radicals. A dose of nanocarriers of 5 mg·mL{sup −1} has led to a drastic decrease in tumor cell proliferation even in the absence of an antitumor drug (e.g. about 50% viability for MDA-MB 231 cell line and 60% viability for HeLa cell line). A comparative survival profile of normal and tumor cells, which were exposed to an effective dose of 2.5 mg·mL{sup −1} lipid nanocarriers, has revealed a death rate of 20% for normal B16 cells and of 40% death rate for MDA-MB 231 and HeLa tumor cells. The results in this study imply that lipid nanocarriers based on grape seed oil in association with laurel leaf oil could be a candidate to reduce the delivery system toxicity and may significantly improve the therapeutic efficacy of antitumor drugs in clinical applications. - Highlights: • Functional lipid nanocarriers with unique features and broad spectrum effectiveness • Lipid nanocarriers based on laureal leaf oil (LLO) and grape seed oil (GSO) • Antioxidant activity has reached 98% for nanocarriers containing 25% GSO and 2% LLO. • LLO exerts a significant cytotoxic effect against HeLa and MDA-MB 231 tumor

  6. Lipid nanocarriers based on natural oils with high activity against oxygen free radicals and tumor cell proliferation

    International Nuclear Information System (INIS)

    The development of nano-dosage forms of phytochemicals represents a significant progress of the scientific approach in the biomedical research. The aim of this study was to assess the effectiveness of lipid nanocarriers based on natural oils (grape seed oil, fish oil and laurel leaf oil) in counteracting free radicals and combating certain tumor cells. No drug was encapsulated in the nanocarriers. The cytotoxic effect exerted by bioactive nanocarriers against two tumor cells, MDA-MB 231 and HeLa cell lines, and two normal cells, L929 and B16 cell lines, was measured using the MTT assay, while oxidative damage was assessed by measuring the total antioxidant activity using chemiluminescence analysis. The best performance was obtained for nanocarriers based on an association of grape seed and laurel leaf oils, with a capacity to scavenge about 98% oxygen free radicals. A dose of nanocarriers of 5 mg·mL−1 has led to a drastic decrease in tumor cell proliferation even in the absence of an antitumor drug (e.g. about 50% viability for MDA-MB 231 cell line and 60% viability for HeLa cell line). A comparative survival profile of normal and tumor cells, which were exposed to an effective dose of 2.5 mg·mL−1 lipid nanocarriers, has revealed a death rate of 20% for normal B16 cells and of 40% death rate for MDA-MB 231 and HeLa tumor cells. The results in this study imply that lipid nanocarriers based on grape seed oil in association with laurel leaf oil could be a candidate to reduce the delivery system toxicity and may significantly improve the therapeutic efficacy of antitumor drugs in clinical applications. - Highlights: • Functional lipid nanocarriers with unique features and broad spectrum effectiveness • Lipid nanocarriers based on laureal leaf oil (LLO) and grape seed oil (GSO) • Antioxidant activity has reached 98% for nanocarriers containing 25% GSO and 2% LLO. • LLO exerts a significant cytotoxic effect against HeLa and MDA-MB 231 tumor cells. • 50

  7. Activation of p38, p21, and NRF-2 Mediates Decreased Proliferation of Human Dental Pulp Stem Cells Cultured under 21% O2

    Directory of Open Access Journals (Sweden)

    Marya El Alami

    2014-10-01

    Full Text Available High rates of stem cell proliferation are important in regenerative medicine and in stem cell banking for clinical use. Ambient oxygen tensions (21% O2 are normally used for in vitro culture, but physiological levels in vivo range between 3% and 6% O2. We compared proliferation of human dental pulp stem cells (hDPSCs cultured under 21% versus 3% O2. The rate of hDPSC proliferation is significantly lower at 21% O2 compared to physiological oxygen levels due to enhanced oxidative stress. Under 21% O2, increased p38 phosphorylation led to activation of p21. Increased generation of reactive oxygen species and p21 led to activation of the NRF-2 signaling pathway. The upregulation of NRF-2 antioxidant defense genes under 21% O2 may interact with cell-cycle-related proteins involved in regulating cell proliferation. Activation of p38/p21/NRF-2 in hDPSCs cultured under ambient oxygen tension inhibits stem cell proliferation and upregulates NRF-2 antioxidant defenses.

  8. Activation of p38, p21, and NRF-2 mediates decreased proliferation of human dental pulp stem cells cultured under 21% O2.

    Science.gov (United States)

    El Alami, Marya; Viña-Almunia, Jose; Gambini, Juan; Mas-Bargues, Cristina; Siow, Richard C M; Peñarrocha, Miguel; Mann, Giovanni E; Borrás, Consuelo; Viña, Jose

    2014-10-14

    High rates of stem cell proliferation are important in regenerative medicine and in stem cell banking for clinical use. Ambient oxygen tensions (21% O2) are normally used for in vitro culture, but physiological levels in vivo range between 3% and 6% O2. We compared proliferation of human dental pulp stem cells (hDPSCs) cultured under 21% versus 3% O2. The rate of hDPSC proliferation is significantly lower at 21% O2 compared to physiological oxygen levels due to enhanced oxidative stress. Under 21% O2, increased p38 phosphorylation led to activation of p21. Increased generation of reactive oxygen species and p21 led to activation of the NRF-2 signaling pathway. The upregulation of NRF-2 antioxidant defense genes under 21% O2 may interact with cell-cycle-related proteins involved in regulating cell proliferation. Activation of p38/p21/NRF-2 in hDPSCs cultured under ambient oxygen tension inhibits stem cell proliferation and upregulates NRF-2 antioxidant defenses.

  9. Differential effects of peroxisome proliferator-activated receptor agonists on doxorubicin-resistant human myelogenous leukemia (K562/DOX) cells.

    Science.gov (United States)

    Yousefi, B; Samadi, N; Baradaran, B; Rameshknia, V; Shafiei-Irannejad, V; Majidinia, M; Targhaze, N; Zarghami, N

    2015-01-01

    P-glycoprotein (P-gp)-mediated multidrug resistance (MDR) in tumor cells is still a main obstacle for the chemotherapeutic treatment of cancers. Therefore, identification of safe and effective MDR reversing compounds with minimal adverse side effects is an important approach in the cancer treatment. Studies show that peroxisome proliferator-activated receptor (PPARs) ligands can inhibit cell growth in many cancers. Here, we investigated the effect of different PPAR agonists include fenofibrate, troglitazone and aleglitazar on doxorubicin-resistant human myelogenous leukemia (K562/DOX) cells. The effects of doxorubicin (DOX) following treatment with PPAR agonists on cell viability were evaluated using MTT assay and the reversal fold (RF) values. Rhodamine123 (Rh123) assays were used to determine P-gp functioning. P-gp mRNA/protein expression was measured by quantitative reverse transcription polymerase chain reaction (qRT-PCR) and western blot analysis after incubation with troglitazone and aleglitazar. Our results showed that troglitazone and aleglitazar significantly enhanced the cytotoxicity of DOX and decreased the RF values in K562/DOX cells, however, no such results were found for fenofibrate. Troglitazone and aleglitazar significantly down regulated P-gp expression in K562/DOX cells; in addition, the present study revealed that aleglitazar elevated intracellular accumulation of Rh123in K562/DOX cells as short-term effects, which also contribute to the reversal of MDR. These findings show that troglitazone and especially aleglitazar exhibited potent effects in the reversal of P-gp-mediated MDR, suggesting that these compounds may be effective for combination therapy strategies and circumventing MDR in K562/DOX cells to other conventional chemotherapeutic drugs. PMID:26718439

  10. Gamma (γ) tocopherol upregulates peroxisome proliferator activated receptor (PPAR) gamma (γ) expression in SW 480 human colon cancer cell lines

    International Nuclear Information System (INIS)

    Tocopherols are lipid soluble antioxidants that exist as eight structurally different isoforms. The intake of γ-tocopherol is higher than α-tocopherol in the average US diet. The clinical results of the effects of vitamin E as a cancer preventive agent have been inconsistent. All published clinical trials with vitamin E have used α-tocopherol. Recent epidemiological, experimental and molecular studies suggest that γ-tocopherol may be a more potent chemopreventive form of vitamin E compared to the more-studied α-tocopherol. γ-Tocopherol exhibits differences in its ability to detoxify nitrogen dioxide, growth inhibitory effects on selected cancer cell lines, inhibition of neoplastic transformation in embryonic fibroblasts, and inhibition of cyclooxygenase-2 (COX-2) activity in macrophages and epithelial cells. Peroxisome proliferator activator receptor γ (PPARγ) is a promising molecular target for colon cancer prevention. Upregulation of PPARγ activity is anticarcinogenic through its effects on downstream genes that affect cellular proliferation and apoptosis. The thiazolidine class of drugs are powerful PPARγ ligands. Vitamin E has structural similarity to the thiazolidine, troglitazone. In this investigation, we tested the effects of both α and γ tocopherol on the expression of PPARγ mRNA and protein in SW 480 colon cancer cell lines. We also measured the intracellular concentrations of vitamin E in SW 480 colon cancer cell lines. We have discovered that the α and γ isoforms of vitamin E upregulate PPARγ mRNA and protein expression in the SW480 colon cancer cell lines. γ-Tocopherol is a better modulator of PPARγ expression than α-tocopherol at the concentrations tested. Intracellular concentrations increased as the vitamin E concentration added to the media was increased. Further, γ-tocopherol-treated cells have higher intracellular tocopherol concentrations than those treated with the same concentrations of α-tocopherol. Our data suggest that

  11. TLR5 signaling enhances the proliferation of human allogeneic CD40-activated B cell induced CD4hiCD25+ regulatory T cells.

    Directory of Open Access Journals (Sweden)

    Ping-Lung Chan

    Full Text Available Although diverse functions of different toll-like receptors (TLR on human natural regulatory T cells have been demonstrated recently, the role of TLR-related signals on human induced regulatory T cells remain elusive. Previously our group developed an ex vivo high-efficient system in generating human alloantigen-specific CD4(hiCD25(+ regulatory T cells from naïve CD4(+CD25(- T cells using allogeneic CD40-activated B cells as stimulators. In this study, we investigated the role of TLR5-related signals on the generation and function of these novel CD4(hiCD25(+ regulatory T cells. It was found that induced CD4(hiCD25(+ regulatory T cells expressed an up-regulated level of TLR5 compared to their precursors. The blockade of TLR5 using anti-TLR5 antibodies during the co-culture decreased CD4(hiCD25(+ regulatory T cells proliferation by induction of S phase arrest. The S phase arrest was associated with reduced ERK1/2 phosphorylation. However, TLR5 blockade did not decrease the CTLA-4, GITR and FOXP3 expressions, and the suppressive function of CD4(hiCD25(+ regulatory T cells. In conclusion, we discovered a novel function of TLR5-related signaling in enhancing the proliferation of CD4(hiCD25(+ regulatory T cells by promoting S phase progress but not involved in the suppressive function of human CD40-activated B cell-induced CD4(hiCD25(+ regulatory T cells, suggesting a novel role of TLR5-related signals in the generation of induced regulatory T cells.

  12. In vitro effects of rituximab on the proliferation, activation and differentiation of human B cells.

    NARCIS (Netherlands)

    Kamburova, E.G.; Koenen, H.J.P.M.; Boon, L.; Hilbrands, L.B.; Joosten, I.

    2012-01-01

    Rituximab is a chimeric anti-CD20 monoclonal antibody (mAb) used in B-cell malignancies, various autoimmune disorders and organ transplantation. Although administration of a single dose of rituximab results in full B-cell depletion in peripheral blood, there remains a residual B-cell population in s

  13. NKX3.1 Activates Expression of IGFBP-3 to Mediate IGF-I Signaling and Cell Proliferation

    Science.gov (United States)

    Muhlbradt, Erin; Asatiani, Ekaterina; Ortner, Elizabeth; Wang, Antai; Gelmann, Edward P.

    2013-01-01

    NKX3.1 is a homeobox gene that codes for a haploinsufficient prostate cancer tumor suppressor. NKX3.1 protein levels are down regulated in the majority of primary prostate cancer tissues. NKX3.1 expression in PC-3 cells increased IGFBP-3 mRNA expression 10-fold as determined by expression microarray analysis. In both stably and transiently transfected PC-3 cells and in LNCaP cells NKX3.1 expression increased IGFBP-3 mRNA and protein expression. In prostates of Nkx3.1 gene-targeted mice Igfbp-3 mRNA levels correlated with Nkx3.1 copy number. NKX3.1 expression in PC-3 cells attenuated the ability of IGF-I to induce phosphorylation of IGF-IR, IRS-1, PI3-kinase, and AKT. The effect of NKX3.1 on IGF-I signaling was not seen when cells were exposed to long-R3-IGF-I, an IGF-1 variant peptide that does not bind to IGFBP-3. Additionally, siRNA-induced knock down of IGFBP-3 expression partially reversed the attenuation of IGF-1R signaling by NKX3.1 and abrogated NKX3.1 suppression of PC-3 cell proliferation. Thus there is a close relationship in vitro and in vivo between NKX3.1 and IGFBP-3. The growth suppressive effects of NKX3.1 in prostate cells are mediated, in part, by activation of IGFBP-3 expression. PMID:19258508

  14. Regulation of cell proliferation by G proteins.

    Science.gov (United States)

    Dhanasekaran, N; Tsim, S T; Dermott, J M; Onesime, D

    1998-09-17

    G Proteins provide signal transduction mechanisms to seven transmembrane receptors. Recent studies have indicated that the alpha-subunits as well as the betagamma-subunits of these proteins regulate several critical signaling pathways involved in cell proliferation, differentiation and apoptosis. Of the 17 alpha-subunits that have been cloned, at least ten of them have been shown to couple mitogenic signaling in fibroblast cells. Activating mutations in G alpha(s), G alpha(i)2, and G alpha12 have been correlated with different types of tumors. In addition, the ability of the betagamma-subunits to activate mitogenic pathways in different cell-types has been defined. The present review briefly summarizes the diverse and novel signaling pathways regulated by the alpha- as well as the betagamma-subunits of G proteins in regulating cell proliferation. PMID:9779986

  15. Signal transducer and activator of transcription 5 activation is sufficient to drive transcriptional induction of cyclin D2 gene and proliferation of rat pancreatic beta-cells

    DEFF Research Database (Denmark)

    Friedrichsen, Birgitte N; Richter, Henrijette E; Hansen, Johnny A;

    2003-01-01

    cells transiently transfected with a cyclin D2 promoter-reporter construct revealed a 3- to 5-fold increase of transcriptional activity in response to hGH stimulation. Furthermore, coexpression of a constitutive active STAT5 mutant (either CA-STAT5a or CA-STAT5b) was sufficient to drive transactivation......-STAT5b stimulated transcriptional activation of the cyclin D2 promoter and induced hGH-independent proliferation in these cells. In primary beta-cells, adenovirus-mediated expression of CA-STAT5b profoundly stimulated DNA-synthesis (5.3-fold over control) in the absence of hGH. Our studies indicate...

  16. CYP2S1 depletion enhances colorectal cell proliferation is associated with PGE2-mediated activation of β-catenin signaling

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Chao [Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders (Ministry of Education), Shanghai Jiao Tong University, Shanghai 200030 (China); College of Life Science, Anhui Normal University, Wuhu 241000, Anhui (China); Li, Changyuan [College of Life Science, Anhui Normal University, Wuhu 241000, Anhui (China); Li, Minle; Tong, Xuemei [Department of Biochemistry and Molecular Cell Biology, Shanghai Key Laboratory for Tumor Microenvironment and Inflammation, Shanghai Jiao Tong University School of Medicine, Shanghai 200025 (China); Hu, Xiaowen; Yang, Xuhan [Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders (Ministry of Education), Shanghai Jiao Tong University, Shanghai 200030 (China); Yan, Xiaomei [School of Life Sciences & Biotechnology, Shanghai JiaoTong University, Shanghai 200240 (China); He, Lin, E-mail: helinhelin@gmail.com [Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders (Ministry of Education), Shanghai Jiao Tong University, Shanghai 200030 (China); Wan, Chunling, E-mail: clwan@sjtu.edu.cn [Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders (Ministry of Education), Shanghai Jiao Tong University, Shanghai 200030 (China)

    2015-02-15

    Colorectal epithelial cancer is one of the most common cancers in the world and its 5-year survival rate is still relatively low. Cytochrome P450 (CYP) enzymes in epithelial cells lining the alimentary tract play an important role in the oxidative metabolism of a wide range of xenobiotics, including (pro-)carcinogens and endogenous compounds. Although CYP2S1, a member of CYP family, strongly expressed in many extrahepatic tissues, the role of CYP2S1 in cancer remains unclear. To investigate whether CYP2S1 involves in colorectal carcinogenesis, cell proliferation was analyzed in HCT116 cells depleted of CYP2S1 using small hairpin interfering RNA. Our data show that CYP2S1 knockdown promotes cell proliferation through increasing the level of endogenous prostaglandin E2(PGE2). PGE2, in turn, reduces phosphorylation of β-catenin and activates β-catenin signaling, which contributes to the cell proliferation. Furthermore, CYP2S1 knockdown increase tumor growth in xenograft mouse model. In brief, these results demonstrate that CYP2S1 regulates colorectal cancer growth through associated with PGE2-mediated activation of β-catenin signaling. - Highlights: • Knockdown of CYP2S1 expression improve HCT116 cell proliferation in vitro and in vivo. • Elevate PGE2 production in CYP2S1 knockdown cell is associated with its proliferation. • Elevate PGE2 level in CYP2S1 knockdown cells enhance β-catenin accumulation. • β-catenin activate TCF/LEF and target gene expression thus promote cell proliferation.

  17. Silica nanoparticles increase human adipose tissue-derived stem cell proliferation through ERK1/2 activation

    Directory of Open Access Journals (Sweden)

    Kim KJ

    2015-03-01

    Full Text Available Ki Joo Kim,1,2 Young Ae Joe,3 Min Kyoung Kim,1,2 Su Jin Lee,1 Yeon Hee Ryu,1,2 Dong-Woo Cho,4,5 Jong Won Rhie1,2 1Department of Plastic Surgery, College of Medicine, 2Department of Molecular Biomedicine, 3Cancer Research Institute and Department of Medical Lifescience, The Catholic University of Korea, Seoul, Republic of Korea; 4Department of Mechanical Engineering, Pohang University of Science and Technology, Gyeongbuk, Republic of Korea; 5Department of Integrative Bioscience and Bioengineering, Pohang University of Science and Technology, Gyeongbuk, Republic of Korea Background: Silicon dioxide composites have been found to enhance the mechanical properties of scaffolds and to support growth of human adipose tissue-derived stem cells (hADSCs both in vitro and in vivo. Silica (silicon dioxide alone exists as differently sized particles when suspended in culture medium, but it is not clear whether particle size influences the beneficial effect of silicon dioxide on hADSCs. In this study, we examined the effect of different sized particles on growth and mitogen-activated protein kinase signaling in hADSCs.Methods: Silica gel was prepared by a chemical reaction using hydrochloric acid and sodium silicate, washed, sterilized, and suspended in serum-free culture medium for 48 hours, and then sequentially filtered through a 0.22 µm filter (filtrate containing nanoparticles smaller than 220 nm; silica NPs. hADSCs were incubated with silica NPs or 3 µm silica microparticles (MPs, examined by transmission electron microscopy, and assayed for cell proliferation, apoptosis, and mitogen-activated protein kinase signaling.Results: Eighty-nine percent of the silica NPs were around 50–120 nm in size. When hADSCs were treated with the study particles, silica NPs were observed in endocytosed vacuoles in the cytosol of hADSCs, but silica MPs showed no cell entry. Silica NPs increased the proliferation of hADSCs, but silica MPs had no significant effect in

  18. Peroxisome Proliferator-Activated Receptor γ Regulates the Expression of Lipid Phosphate Phosphohydrolase 1 in Human Vascular Endothelial Cells

    Directory of Open Access Journals (Sweden)

    Yazi Huang

    2014-01-01

    Full Text Available Lipid phosphate phosphohydrolase 1 (LPP1, a membrane ectophosphohydrolase regulating the availability of bioactive lipid phosphates, plays important roles in cellular signaling and physiological processes such as angiogenesis and endothelial migration. However, the regulated expression of LPP1 remains largely unknown. Here, we aimed to examine a role of peroxisome proliferator-activated receptor γ (PPARγ in the transcriptional control of LPP1 gene expression. In human umbilical vein endothelial cells (HUVECs, quantitative reverse transcriptase polymerase chain reaction (qRT-PCR demonstrated that activation of PPARγ increased the mRNA level of LPP1. Chromatin immunoprecipitation assay showed that PPARγ binds to the putative PPAR-responsive elements (PPREs within the 5′-flanking region of the human LPP1 gene. Genomic fragment containing 1.7-kilobase of the promoter region was cloned by using PCR. The luciferase reporter assays demonstrated that overexpression of PPARγ and rosiglitazone, a specific ligand for PPARγ, could significantly upregulate the reporter activity. However, site-directed mutagenesis of the PPRE motif abolished the induction. In conclusion, our results demonstrated that PPARγ transcriptionally activated the expression of LPP1 gene in ECs, suggesting a potential role of PPARγ in the metabolism of phospholipids.

  19. Protein kinase D stabilizes aldosterone-induced ERK1/2 MAP kinase activation in M1 renal cortical collecting duct cells to promote cell proliferation.

    LENUS (Irish Health Repository)

    McEneaney, Victoria

    2010-01-01

    Aldosterone elicits transcriptional responses in target tissues and also rapidly stimulates the activation of protein kinase signalling cascades independently of de novo protein synthesis. Here we investigated aldosterone-induced cell proliferation and extra-cellular regulated kinase 1 and 2 (ERK1\\/2) mitogen activated protein (MAP) kinase signalling in the M1 cortical collecting duct cell line (M1-CCD). Aldosterone promoted the proliferative growth of M1-CCD cells, an effect that was protein kinase D1 (PKD1), PKCdelta and ERK1\\/2-dependent. Aldosterone induced the rapid activation of ERK1\\/2 with peaks of activation at 2 and 10 to 30 min after hormone treatment followed by sustained activation lasting beyond 120 min. M1-CCD cells suppressed in PKD1 expression exhibited only the early, transient peaks in ERK1\\/2 activation without the sustained phase. Aldosterone stimulated the physical association of PKD1 with ERK1\\/2 within 2 min of treatment. The mineralocorticoid receptor (MR) antagonist RU28318 inhibited the early and late phases of aldosterone-induced ERK1\\/2 activation, and also aldosterone-induced proliferative cell growth. Aldosterone induced the sub-cellular redistribution of ERK1\\/2 to the nuclei at 2 min and to cytoplasmic sites, proximal to the nuclei after 30 min. This sub-cellular distribution of ERK1\\/2 was inhibited in cells suppressed in the expression of PKD1.

  20. Heat shock protein 70 (Hsp70) stimulates proliferation and cytolytic activity of natural killer cells

    NARCIS (Netherlands)

    Multhoff, G; Mizzen, L; Winchester, CC; Milner, CM; Wenk, S; Eissner, G; Kampinga, HH; Laumbacher, B; Johnson, J

    1999-01-01

    We previously demonstrated that lysis of tumor cells that express Hsp70, the highly stress-inducible member of the HSP70 family, on their plasma membrane is mediated by natural killer (NK) cells. Here, we studied the effects of different proteins of the HSP70 family in combination with interleukin 2

  1. Inhibition of cell proliferation by a selective inhibitor of the Ca{sup 2+}-activated Cl{sup -} channel, Ano1

    Energy Technology Data Exchange (ETDEWEB)

    Mazzone, Amelia; Eisenman, Seth T.; Strege, Peter R. [Enteric NeuroScience Program, Mayo Clinic, Rochester, MN (United States); Yao, Zhen [Laboratory of Molecular Genetics, UCSF, San Francisco, CA (United States); Ordog, Tamas; Gibbons, Simon J. [Enteric NeuroScience Program, Mayo Clinic, Rochester, MN (United States); Farrugia, Gianrico, E-mail: farrugia.gianrico@mayo.edu [Enteric NeuroScience Program, Mayo Clinic, Rochester, MN (United States)

    2012-10-19

    Highlights: Black-Right-Pointing-Pointer T16A{sub inh}-A01 blocked Ano1 currents in HEK cells expressing Ano1. Black-Right-Pointing-Pointer T16A{sub inh}-A01 reduced proliferation in ICC primary cultures and CFPAC-1 cell line. Black-Right-Pointing-Pointer T16A{sub inh}-A01 reduced proliferation of ICC in intact smooth muscle strips. -- Abstract: Background: Ion channels play important roles in regulation of cellular proliferation. Ano1 (TMEM16A) is a Ca{sup 2+}-activated Cl{sup -} channel expressed in several tumors and cell types. In the muscle layers of the gastrointestinal tract Ano1 is selectively expressed in interstitial cells of Cajal (ICC) and appears to be required for normal gastrointestinal slow wave electrical activity. However, Ano1 is expressed in all classes of ICC, including those that do not generate slow waves suggesting that Ano1 may have other functions. Indeed, a role for Ano1 in regulating proliferation of tumors and ICC has been recently suggested. Recently, a high-throughput screen identified a small molecule, T16A{sub inh}-A01 as a specific inhibitor of Ano1. Aim: To investigate the effect of the T16A{sub inh}-A01 inhibitor on proliferation in ICC and in the Ano1-expressing human pancreatic cancer cell line CFPAC-1. Methods: Inhibition of Ano1 was demonstrated by whole cell voltage clamp recordings of currents in cells transfected with full-length human Ano1. The effect of T16A{sub inh}-A01 on ICC proliferation was examined in situ in organotypic cultures of intact mouse small intestinal smooth muscle strips and in primary cell cultures prepared from these tissues. ICC were identified by Kit immunoreactivity. Proliferating ICC and CFPAC-1 cells were identified by immunoreactivity for the nuclear antigen Ki67 or EdU incorporation, respectively. Results: T16A{sub inh}-A01 inhibited Ca{sup 2+}-activated Cl{sup -} currents by 60% at 10 {mu}M in a voltage-independent fashion. Proliferation of ICC was significantly reduced in primary cultures

  2. Lysophosphatidic acid activates peroxisome proliferator activated receptor-γ in CHO cells that over-express glycerol 3-phosphate acyltransferase-1.

    Directory of Open Access Journals (Sweden)

    Cliona M Stapleton

    Full Text Available Lysophosphatidic acid (LPA is an agonist for peroxisome proliferator activated receptor-γ (PPARγ. Although glycerol-3-phosphate acyltransferase-1 (GPAT1 esterifies glycerol-3-phosphate to form LPA, an intermediate in the de novo synthesis of glycerolipids, it has been assumed that LPA synthesized by this route does not have a signaling role. The availability of Chinese Hamster Ovary (CHO cells that stably overexpress GPAT1, allowed us to analyze PPARγ activation in the presence of LPA produced as an intracellular intermediate. LPA levels in CHO-GPAT1 cells were 6-fold higher than in wild-type CHO cells, and the mRNA abundance of CD36, a PPARγ target, was 2-fold higher. Transactivation assays showed that PPARγ activity was higher in the cells that overexpressed GPAT1. PPARγ activity was enhanced further in CHO-GPAT1 cells treated with the PPARγ ligand troglitazone. Extracellular LPA, phosphatidic acid (PA or a membrane-permeable diacylglycerol had no effect, showing that PPARγ had been activated by LPA generated intracellularly. Transient transfection of a vector expressing 1-acylglycerol-3-phosphate acyltransferase-2, which converts endogenous LPA to PA, markedly reduced PPARγ activity, as did over-expressing diacylglycerol kinase, which converts DAG to PA, indicating that PA could be a potent inhibitor of PPARγ. These data suggest that LPA synthesized via the glycerol-3-phosphate pathway can activate PPARγ and that intermediates of de novo glycerolipid synthesis regulate gene expression.

  3. Attenuation of Telomerase Activity by siRNA Targeted Telomerase RNA Leads to Apoptosis and Inhibition of Proliferation in Human Renal Carcinoma Cells

    Institute of Scientific and Technical Information of China (English)

    Rumin Wen; Junjie Liu; Wang Li; Wenfa Yang; Lijun Mao; Junnian Zheng

    2006-01-01

    OBJECTIVE Telomerase is an attractive molecular target for cancer therapy because the activation of telomerase is one of the key steps in cell immortalization and carcinogenesis. RNA interference using small-interfering RNA (siRNA) has been demonstrated to be an effective method for inhibiting the expression of a given gene in human cells. The aim of the present study was to investigate whether inhibition of telomerase activity by siRNA targeted against human telomerase RNA (hTR) can inhibit proliferation and induce apoptotic cell death in human renal carcinoma cells(HRCCs).METHODS The siRNA duplexes for hTR were synthesized and 786-O HRCCs were transfected with different concentrations of hTR-siRNA. The influence on the hTR mRNA level, telomerase activity, as well as the effect on cell proliferation and apoptosis was examined.RESULTS Anti-hTR siRNA treatment of HRCCs resulted in specific reduction of hTR mRNA and inhibition of telomerase activity. Additionally,significant inhibition of proliferation and induction of apoptosis were observed.CONCLUSION siRNA against the hTR gene can inhibit proliferation and induce apoptosis by blocking telomerase activity of HRCCs. Specific hTR inhibition by siRNA represents a promising new option for renal cancer treatment.

  4. Scorpion venom component III inhibits cell proliferation by modulating NF-κB activation in human leukemia cells

    OpenAIRE

    SONG, XIANGFENG; Zhang, Guojun; SUN, AIPING; Guo, Jiqiang; TIAN, ZHONGWEI; Wang, Hui; Liu, Yufeng

    2012-01-01

    Scorpion venom contains various groups of compounds that exhibit anticancer activity against a variety of malignancies through a poorly understood mechanism. While the aberrant activation of nuclear factor κB (NF-κB) has been linked with hematopoietic malignancies, we hypothesized that scorpion venom mediates its effects by modulating the NF-κB signaling pathway. In the present study, we examined the effects of scorpion venom component III (SVCIII) on the human leukemia cell lines THP-1 and J...

  5. Polydatin inhibits the oxidative stress-induced proliferation of vascular smooth muscle cells by activating the eNOS/SIRT1 pathway.

    Science.gov (United States)

    Ma, Yi; Gong, Xun; Mo, Yingli; Wu, Saizhu

    2016-06-01

    Oxidative stress-mediated proliferation of vascular smooth muscle cells (VSMCs) contributes to plaque formation and the progression of atherosclerosis. Polydatin is a derivative of resveratrol, and is widely present in certain herbal medications used for the treatment of cardiovascular diseases. In the present study, we examined whether polydatin was capable of attenuating VSMC proliferation induced by oxidative stress as well as the potential involvement of the endothelial nitric oxide synthetase (eNOS)/SIRT1 pathway. Briefly, VSMCs were exposed to H2O2 for 24 h in the absence or presence of polydatin (10-100 µM) prior to performing a cell proliferation assay. In mechanistic studies, the cells were incubated with the silent information regulator 1 (SIRT1) inhibitor, EX527, or the eNOS inhibitor, L-NAME, prior to polydatin treatment. The results showed that polydatin inhibited VSMC proliferation and the level of reactive oxygen species, increased the expression of Kip1/p27, SIRT1 and eNOS, whereas the expression of cyclin B1, Cdk1 and c-myc was decreased. The number of cells in the G2/M phase was increased. Pre-treatment with L-NAME attenuated the inhibitory effects of polydatin on cell proliferation, inhibited the expression of SIRT1 and the phosphorylation of eNOS. Pre-treatment with EX527 also attenuated the inhibitory effects of polydatin on cell proliferation, but failed to reduce the activation of eNOS and the production of nitric oxide. Taken together, these findings suggest that, polydatin inhibited the oxidative stress-induced proliferation of VMSCs by activating the eNOS/SIRT1 pathway. PMID:27081912

  6. One novel quinoxaline derivative as a potent human cyclophilin A inhibitor shows highly inhibitory activity against mouse spleen cell proliferation.

    Science.gov (United States)

    Li, Jian; Chen, Jing; Zhang, Li; Wang, Feng; Gui, Chunshan; Zhang, Li; Qin, Yu; Xu, Qiang; Liu, Hong; Nan, Fajun; Shen, Jingkang; Bai, Donglu; Chen, Kaixian; Shen, Xu; Jiang, Hualiang

    2006-08-15

    Cyclophilin A (CypA) is a ubiquitous cellular enzyme playing critical roles in many biological processes, and its inhibitor has been reported to have potential immunosuppressive activity. In this work, we reported a novel quinoxaline derivative, 2,3-di(furan-2-yl)-6-(3-N,N-diethylcarbamoyl-piperidino)carbonylamino quinoxaline (DC838, 3), which was confirmed to be a potent inhibitor against human CypA. By using the surface plasmon resonance (SPR) and fluorescence titration techniques, the kinetic analysis of CypA/DC838 interaction was quantitatively performed. CypA peptidyl prolyl cis-trans isomerase (PPIase) activity inhibition assay showed that DC838 demonstrated highly CypA PPIase inhibitory activity. In vivo assay results showed that DC838 could inhibit mouse spleen cell proliferation induced by concanavalin A (Con A). Molecular docking simulation further elucidated the specific DC838 binding to CypA at the atomic level. The current work should provide useful information in the discovery of immunosuppressor based on CypA inhibitor.

  7. Defect density in multiwalled carbon nanotubes influences ovalbumin adsorption and promotes macrophage activation and CD4(+) T-cell proliferation.

    Science.gov (United States)

    Bai, Wei; Raghavendra, Achyut; Podila, Ramakrishna; Brown, Jared M

    2016-01-01

    Carbon nanotubes (CNTs) are of great interest for the development of drugs and vaccines due to their unique physicochemical properties. The high surface area to volume ratio and delocalized pi-electron cloud of CNTs promote binding of proteins to the surface forming a protein corona. This unique feature of CNTs has been recognized for potential delivery of antigens for strong and long-lasting antigen-specific immune responses. Based on an earlier study that demonstrated increased protein binding, we propose that carboxylated multiwalled CNTs (MWCNTs) can function as an improved carrier to deliver antigens such as ovalbumin (OVA). To test this hypothesis, we coated carboxylated MWCNTs with OVA and measured uptake and activation of antigen-presenting cells (macrophages) and their ability to stimulate CD4(+) T-cell proliferation. We employed two types of carboxylated MWCNTs with different surface areas and defects (MWCNT-2 and MWCNT-30). MWCNT-2 and MWCNT-30 have surface areas of ~215 m(2)/g and 94 m(2)/g, respectively. The ratios of D- to G-band areas (I D/I G) were 0.97 and 1.37 for MWCNT-2 and MWCNT-30, respectively, samples showing that MWCNT-30 contained more defects. The increase in defects in MWCNT-30 led to increased binding of OVA as compared to MWCNT-2 (1,066±182 μg/mL vs 582±41 μg/mL, respectively). Both types of MWCNTs, along with MWCNT-OVA complexes, showed no observable toxicity to bone-marrow-derived macrophages up to 5 days. Surprisingly, we found that MWCNT-OVA complex significantly increased the expression of major histocompatibility complex class II on macrophages and production of pro-inflammatory cytokines (tumor necrosis factor-α and interleukin 6), while MWCNTs without OVA protein corona did not. The coculture of MWCNT-OVA-complex-treated macrophages and OVA-specific CD4(+) T-cells isolated from OT-II mice demonstrated robust proliferation of CD4(+) T-cells. This study provides strong evidence for a role for defects in carboxylated MWCNTs

  8. Defect density in multiwalled carbon nanotubes influences ovalbumin adsorption and promotes macrophage activation and CD4+ T-cell proliferation

    Science.gov (United States)

    Bai, Wei; Raghavendra, Achyut; Podila, Ramakrishna; Brown, Jared M

    2016-01-01

    Carbon nanotubes (CNTs) are of great interest for the development of drugs and vaccines due to their unique physicochemical properties. The high surface area to volume ratio and delocalized pi-electron cloud of CNTs promote binding of proteins to the surface forming a protein corona. This unique feature of CNTs has been recognized for potential delivery of antigens for strong and long-lasting antigen-specific immune responses. Based on an earlier study that demonstrated increased protein binding, we propose that carboxylated multiwalled CNTs (MWCNTs) can function as an improved carrier to deliver antigens such as ovalbumin (OVA). To test this hypothesis, we coated carboxylated MWCNTs with OVA and measured uptake and activation of antigen-presenting cells (macrophages) and their ability to stimulate CD4+ T-cell proliferation. We employed two types of carboxylated MWCNTs with different surface areas and defects (MWCNT-2 and MWCNT-30). MWCNT-2 and MWCNT-30 have surface areas of ~215 m2/g and 94 m2/g, respectively. The ratios of D- to G-band areas (ID/IG) were 0.97 and 1.37 for MWCNT-2 and MWCNT-30, respectively, samples showing that MWCNT-30 contained more defects. The increase in defects in MWCNT-30 led to increased binding of OVA as compared to MWCNT-2 (1,066±182 μg/mL vs 582±41 μg/mL, respectively). Both types of MWCNTs, along with MWCNT–OVA complexes, showed no observable toxicity to bone-marrow-derived macrophages up to 5 days. Surprisingly, we found that MWCNT–OVA complex significantly increased the expression of major histocompatibility complex class II on macrophages and production of pro-inflammatory cytokines (tumor necrosis factor-α and interleukin 6), while MWCNTs without OVA protein corona did not. The coculture of MWCNT–OVA-complex-treated macrophages and OVA-specific CD4+ T-cells isolated from OT-II mice demonstrated robust proliferation of CD4+ T-cells. This study provides strong evidence for a role for defects in carboxylated MWCNTs and

  9. Transcription factor activity of estrogen receptor α activation upon nonylphenol or bisphenol A treatment enhances the in vitro proliferation, invasion, and migration of neuroblastoma cells

    Science.gov (United States)

    Ma, Hongda; Yao, Yao; Wang, Changli; Zhang, Liyu; Cheng, Long; Wang, Yiren; Wang, Tao; Liang, Erguang; Jia, Hui; Ye, Qinong; Hou, Mingxiao; Feng, Fan

    2016-01-01

    Many kinds of endocrine-disrupting chemicals (EDCs), for example, the environmental estrogens bisphenol A and nonylphenol, may regulate the activity of estrogen receptor α (ERα) and therefore induce potential disruption of normal endocrine function. However, the involvement of EDCs in human cancers, especially in endocrine-related cancer neuroblastoma regulation, is not very clear. In this work, results showed that upon bisphenol A or nonylphenol treatment, the transcription factor activity of ERα was significantly increased in neuroblastoma cell line SH-SY5Y. Bisphenol A and nonylphenol could enhance ERα activity via recruiting it to the target gene promoter. Furthermore, treatment of bisphenol A and nonylphenol enhanced the in vitro proliferation, invasion, and migration ability of neuroblastoma cells. By investigating the role of EDC-induced ERα upregulation, our data extend the understanding of the function of EDCs and further suggest that ERα might be a potential therapeutic target in human neuroblastoma treatment. PMID:27366082

  10. Hippocampal cell proliferation across the day : Increase by running wheel activity, but no effect of sleep and wakefulness

    NARCIS (Netherlands)

    van der Borght, K; Ferrari, F; Klauke, K; Roman, Viktor; Havekes, R; Sgoifo, A; van der Zee, EA; Meerlo, P

    2006-01-01

    The present study investigated whether proliferation of hippocampal progenitors is subject to circadian modulation. Mice were perfused using 3 h intervals throughout the light-dark cycle and brains were stained for Ki-67. Since Ki-67 is not expressed during the G0 phase of the cell cycle, we expecte

  11. Glucagon-like peptide 2 dose-dependently activates intestinal cell survival and proliferation in neonatal piglets

    DEFF Research Database (Denmark)

    Burrin, Douglas G; Stoll, Barbara; Guan, Xinfu;

    2005-01-01

    Glucagon-like peptide 2 (GLP-2) is a gut hormone that stimulates mucosal growth in total parenteral nutrition (TPN)-fed piglets; however, the dose-dependent effects on apoptosis, cell proliferation, and protein synthesis are unknown. We studied 38 TPN-fed neonatal piglets infused iv with either s...

  12. Bioactive interruptins A and B from Cyclosorus terminans: antibacterial, anticancer, stem cell proliferation and ROS scavenging activities

    Directory of Open Access Journals (Sweden)

    Sireewan Kaewsuwan

    2015-06-01

    Full Text Available The fern Cyclosorus terminans has long been consumed as a vegetable in northern Thailand. Nevertheless there has been no definitive investigation on its biological properties. Here we have isolated three coumarin derivatives, interruptins A, B and C from C. terminans. Interruptin A exhibited antibacterial activity against four Gram-positive bacteria including methicillin-sensitive Staphylococcus aureus (MSSA, methicillin-resistant S. aureus (MRSA, S. epidermidis and Bacillus subtilis with MIC values as low as 2 mg/ml. Interruptins A and B inhibited the growth of MCF-7 human breast and HT-29 human colon cancer cells with IC50 values as low as 0.13 ng/ml yet stimulated proliferation of normal ASC stem cells with no signs of toxicity. Moreover, both interruptins A and B showed a powerful capacity for scavenging intracellular ROS and performed an anti-apoptotic effect against extracellular oxidative damage by H2O2 . As a result, it is suggested that this lower plant could find a use in natural diets for treatment of infection with a special reference to MRSA, controlling breast and colon cancers, and reducing oxidative stress induced by ROS.

  13. Cell death is induced by ciglitazone, a peroxisome proliferator-activated receptor {gamma} (PPAR{gamma}) agonist, independently of PPAR{gamma} in human glioma cells

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Myoung Woo; Kim, Dae Seong; Kim, Hye Ryung; Kim, Hye Jin; Yang, Jin Mo; Ryu, Somi; Noh, Yoo Hun; Lee, Soo Hyun; Son, Meong Hi; Jung, Hye Lim; Yoo, Keon Hee [Department of Pediatrics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of); Koo, Hong Hoe, E-mail: hhkoo@skku.edu [Department of Pediatrics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of); Sung, Ki Woong, E-mail: kwsped@skku.edu [Department of Pediatrics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)

    2012-01-06

    Highlights: Black-Right-Pointing-Pointer Greater than 30 {mu}M ciglitazone induces cell death in glioma cells. Black-Right-Pointing-Pointer Cell death by ciglitazone is independent of PPAR{gamma} in glioma cells. Black-Right-Pointing-Pointer CGZ induces cell death by the loss of MMP via decreased Akt. -- Abstract: Peroxisome proliferator-activated receptor {gamma} (PPAR{gamma}) regulates multiple signaling pathways, and its agonists induce apoptosis in various cancer cells. However, their role in cell death is unclear. In this study, the relationship between ciglitazone (CGZ) and PPAR{gamma} in CGZ-induced cell death was examined. At concentrations of greater than 30 {mu}M, CGZ, a synthetic PPAR{gamma} agonist, activated caspase-3 and induced apoptosis in T98G cells. Treatment of T98G cells with less than 30 {mu}M CGZ effectively induced cell death after pretreatment with 30 {mu}M of the PPAR{gamma} antagonist GW9662, although GW9662 alone did not induce cell death. This cell death was also observed when cells were co-treated with CGZ and GW9662, but was not observed when cells were treated with CGZ prior to GW9662. In cells in which PPAR{gamma} was down-regulated cells by siRNA, lower concentrations of CGZ (<30 {mu}M) were sufficient to induce cell death, although higher concentrations of CGZ ( Greater-Than-Or-Slanted-Equal-To 30 {mu}M) were required to induce cell death in control T98G cells, indicating that CGZ effectively induces cell death in T98G cells independently of PPAR{gamma}. Treatment with GW9662 followed by CGZ resulted in a down-regulation of Akt activity and the loss of mitochondrial membrane potential (MMP), which was accompanied by a decrease in Bcl-2 expression and an increase in Bid cleavage. These data suggest that CGZ is capable of inducing apoptotic cell death independently of PPAR{gamma} in glioma cells, by down-regulating Akt activity and inducing MMP collapse.

  14. Expression of Peroxisome Proliferator-Activated Receptor γ (PPARγ) in Human Transitional Bladder Cancer and its Role in Inducing Cell Death1

    OpenAIRE

    Guan, You-Fei; Zhang, Ya-hua; Breyer, Richard M.; Davis, Linda; Breyer, Matthew D.

    1999-01-01

    The present study examined the expression and role of the thiazolidinedione (TZD)-activated transcription factor, peroxisome proliferator-activated receptor γ (PPARγ), in human bladder cancers. In situ hybridization shows that PPARγ mRNA is highly expressed in all human transitional epithelial cell cancers (TCCa's) studied (n=11). PPARγ was also expressed in five TCCa cell lines as determined by RNase protection assays and immunoblot. Retinoid X receptor α (RXRα), a 9-cis-retinoic acid stimul...

  15. Topological laser speckle analyzer of differentiation and proliferation activity during morphogenesis in cell cultures

    Directory of Open Access Journals (Sweden)

    Notchenko A.V.

    2011-01-01

    Full Text Available An automated system for morpho-topological determination of cell division phases and structur al differentiation of tissues during morphogenesis was implemented on the basis of topological properties of cell cultures, considered within the framework of set and manifold theories. A simple robotic hardware and software system based on Zeiss microscope with a modified stage and a Velleman manipulator KSR-1 allow to control the laser module position, carrying out the angular irradiation of samples either in transmission or in darkfield or luminescent modes and the subsequent math ematical data processing. This low-budget system can be easily assembled and programmed in any cytomorphological or histomorphologi-cal laboratory. The code for data processing in MATLAB is given at the end of the paper.

  16. Conjugated linoleic acid isomers and their precursor fatty acids regulate peroxisome proliferator-activated receptor subtypes and major peroxisome proliferator responsive element-bearing target genes in HepG2 cell model*

    OpenAIRE

    Benjamin, Sailas; Flotho, Silke; Börchers, Torsten; Spener, Friedrich

    2013-01-01

    The purpose of this study was to examine the induction profiles (as judged by quantitative reverse transcription polymerase chain reaction (qRT-PCR)) of peroxisome proliferator-activated receptor (PPAR) α, β, γ subtypes and major PPAR-target genes bearing a functional peroxisome proliferator responsive element (PPRE) in HepG2 cell model upon feeding with cis-9,trans-11-octadecadienoic acid (9-CLA) or trans-10,cis-12-octadecadienoic acid (10-CLA) or their precursor fatty acids (FAs). HepG2 cel...

  17. Cleavage of E-Cadherin by Matrix Metalloproteinase-7 Promotes Cellular Proliferation in Nontransformed Cell Lines via Activation of RhoA

    Directory of Open Access Journals (Sweden)

    Conor C. Lynch

    2010-01-01

    Full Text Available Perturbations in cell-cell contact machinery occur frequently in epithelial cancers and result in increased cancer cell migration and invasion. Previously, we demonstrated that MMP-7, a protease implicated in mammary and intestinal tumor growth, can process the adherens junction component E-cadherin. This observation leads us to test whether MMP-7 processing of E-cadherin could directly impact cell proliferation in nontransformed epithelial cell lines (MDCK and C57MG. Our goal was to investigate the possibility that MMP-7 produced by cancer cells may have effects on adjacent normal epithelium. Here, we show that MMP-7 processing of E-cadherin mediates, (1 loss of cell-cell contact, (2 increased cell migration, (3 a loss of epithelial cell polarization and (4 increased cell proliferation via RhoA activation. These data demonstrate that MMP-7 promotes epithelial cell proliferation via the processing of E-cadherin and provide insights into the molecular mechanisms that govern epithelial cell growth.

  18. Effect of alkyl glycerophosphate on the activation of peroxisome proliferator-activated receptor gamma and glucose uptake in C2C12 cells

    Energy Technology Data Exchange (ETDEWEB)

    Tsukahara, Tamotsu, E-mail: ttamotsu@shinshu-u.ac.jp [Department of Integrative Physiology and Bio-System Control, Shinshu University School of Medicine, 3-1-1 Asahi, Matsumoto, Nagano 390-8621 (Japan); Haniu, Hisao [Department of Orthopedic Surgery, Shinshu University School of Medicine, 3-1-1 Asahi, Matsumoto, Nagano 390-8621 (Japan); Matsuda, Yoshikazu [Clinical Pharmacology Educational Center, Nihon Pharmaceutical University, Ina-machi, Saitama 362-0806 (Japan)

    2013-04-12

    Highlights: •Alkyl-LPA specifically interacts with PPARγ. •Alkyl-LPA treatments induces lipid accumulation in C2C12 cells. •Alkyl-LPA enhanced glucose uptake in C2C12 cells. •Alkyl-LPA-treated C2C12 cells express increased amounts of GLUT4 mRNA. •Alkyl-LPA is a novel therapeutic agent that can be used for the treatment of obesity and diabetes. -- Abstract: Studies on the effects of lipids on skeletal muscle cells rarely examine the effects of lysophospholipids. Through our recent studies, we identified select forms of phospholipids, such as alkyl-LPA, as ligands for the intracellular receptor peroxisome proliferator-activated receptor gamma (PPARγ). PPARγ is a nuclear hormone receptor implicated in many human diseases, including diabetes and obesity. We previously showed that alkyl-LPA is a specific agonist of PPARγ. However, the mechanism by which the alkyl-LPA–PPARγ axis affects skeletal muscle cells is poorly defined. Our objective in the present study was to determine whether alkyl-LPA and PPARγ activation promotes glucose uptake in skeletal muscle cells. Our findings indicate that PPARγ1 mRNA is more abundant than PPARγ2 mRNA in C2C12 cells. We showed that alkyl-LPA (3 μM) significantly activated PPARγ and increased intracellular glucose levels in skeletal muscle cells. We also showed that incubation of C2C12 cells with alkyl-LPA led to lipid accumulation in the cells. These findings suggest that alkyl-LPA activates PPARγ and stimulates glucose uptake in the absence of insulin in C2C12 cells. This may contribute to the plasma glucose-lowering effect in the treatment of insulin resistance.

  19. Cucurbitane Triterpenoid from Momordica charantia Induces Apoptosis and Autophagy in Breast Cancer Cells, in Part, through Peroxisome Proliferator-Activated Receptor γ Activation

    Directory of Open Access Journals (Sweden)

    Jing-Ru Weng

    2013-01-01

    Full Text Available Although the antitumor activity of the crude extract of wild bitter gourd (Momordica charantia L. has been reported, its bioactive constituents and the underlying mechanism remain undefined. Here, we report that 3β,7β-dihydroxy-25-methoxycucurbita-5,23-diene-19-al (DMC, a cucurbitane-type triterpene isolated from wild bitter gourd, induced apoptotic death in breast cancer cells through peroxisome proliferator-activated receptor (PPAR γ activation. Luciferase reporter assays indicated the ability of DMC to activate PPARγ, and pharmacological inhibition of PPARγ protected cells from DMC's antiproliferative effect. Western blot analysis indicated that DMC suppressed the expression of many PPARγ-targeted signaling effectors, including cyclin D1, CDK6, Bcl-2, XIAP, cyclooxygenase-2, NF-κB, and estrogen receptor α, and induced endoplasmic reticulum stress, as manifested by the induction of GADD153 and GRP78 expression. Moreover, DMC inhibited mTOR-p70S6K signaling through Akt downregulation and AMPK activation. The ability of DMC to activate AMPK in liver kinase (LK B1-deficient MDA-MB-231 cells suggests that this activation was independent of LKB1-regulated cellular metabolic status. However, DMC induced a cytoprotective autophagy presumably through mTOR inhibition, which could be overcome by the cotreatment with the autophagy inhibitor chloroquine. Together, the ability of DMC to modulate multiple PPARγ-targeted signaling pathways provides a mechanistic basis to account for the antitumor activity of wild bitter gourd.

  20. hIgD promotes human Burkitt lymphoma Daudi cell proliferation by accelerated G1/S transition via IgD receptor activity.

    Science.gov (United States)

    Dai, Xing; Wu, YuJing; Jia, XiaoYi; Chang, Yan; Wu, HuaXun; Wang, Chun; Chen, HengShi; Chen, WenSheng; Huang, Qiong; Wei, Wei

    2016-08-01

    The aim of the present study was to investigate the role and molecular mechanism of human IgD (hIgD) on the proliferation of human Burkitt lymphoma Daudi cells in vitro. Logarithmically growing Daudi cells were treated with hIgD for different time periods, and cell proliferation was evaluated by cell counting kit-8 (CCK-8) assay. The expressions of Daudi surface markers and IgD receptor (IgDR) as well as cell cycle and apoptosis were measured by flow cytometry analysis. Our results showed that hIgD stimulation induced proliferation and IgDR expression and reduced the apoptosis of Daudi cells. Treatment with hIgD promoted progression of the cell cycle at the G1/S transition, and this was accompanied by upregulation of c-myc, cyclin D3, and CDK6 as well as downregulation of p16 mRNA and protein levels. Moreover, hIgD treatment also upregulated the expression of tyrosine phosphorylation of 70 kDa protein (IgDR) and p-Lyn. Taken together, these results indicate that hIgD can induce Daudi cell proliferation through activating IgDR to initiate the tyrosine phosphorylation signaling cascade to accelerate the G1/S transition. PMID:26724941

  1. Strain activation of bovine aortic smooth muscle cell proliferation and alignment: study of strain dependency and the role of protein kinase A and C signaling pathways

    Science.gov (United States)

    Mills, I.; Cohen, C. R.; Kamal, K.; Li, G.; Shin, T.; Du, W.; Sumpio, B. E.

    1997-01-01

    Smooth muscle cell (SMC) phenotype can be altered by physical forces as demonstrated by cyclic strain-induced changes in proliferation, orientation, and secretion of macromolecules. However, the magnitude of strain required and the intracellular coupling pathways remain ill defined. To examine the strain requirements for SMC proliferation, we selectively seeded bovine aortic SMC either on the center or periphery of silastic membranes which were deformed with 150 mm Hg vacuum (0-7% center; 7-24% periphery). SMC located in either the center or peripheral regions showed enhanced proliferation compared to cells grown under the absence of cyclic strain. Moreover, SMC located in the center region demonstrated significantly (P proliferation as compared to those in the periphery. In contrast, SMC exposed to high strain (7-24%) demonstrated alignment perpendicular to the strain gradient, whereas SMC in the center (0-7%) remained aligned randomly. To determine the mechanisms of these phenomena, we examined the effect of cyclic strain on bovine aortic SMC signaling pathways. We observed strain-induced stimulation of the cyclic AMP pathway including adenylate cyclase activity and cyclic AMP accumulation. In addition, exposure of SMC to cyclic strain caused a significant increase in protein kinase C (PKC) activity and enzyme translocation from the cytosol to a particulate fraction. Further study was conducted to examine the effect of strain magnitude on signaling, particularly protein kinase A (PKA) activity as well as cAMP response element (CRE) binding protein levels. We observed significantly (P proliferation or alignment. These data characterize the strain determinants for activation of SMC proliferation and alignment. Although strain activated both the AC/cAMP/PKA and the PKC pathways in SMC, singular inhibition of PKA and PKC failed to prevent strain-induced alignment and proliferation, suggesting either their lack of involvement or the multifactorial nature of these

  2. Regulation of skeletal muscle cell plasticity by the peroxisome proliferator-activated receptor gamma coactivator 1alpha

    OpenAIRE

    Handschin, C.

    2010-01-01

    Exercise triggers a pleiotropic response in skeletal muscle, which results in a profound remodeling of this tissue. Physical activity-dependent muscle fiber plasticity is regulated by a number of distinct signaling pathways. Even though most of these pathways are activated by different stimuli and in a temporally and spatially separated manner during exercise, many of the major signal transduction events converge on the peroxisome proliferator-activated receptor gamma coactivator 1alpha (PGC-...

  3. Co-culture with human synovium-derived mesenchymal stem cells inhibits inflammatory activity and increases cell proliferation of sodium nitroprusside-stimulated chondrocytes

    International Nuclear Information System (INIS)

    Highlights: • Co-culture of hSDMSCs with SNP-stimulated chondrocytes improves anti-inflammation. • Co-culture system produces IGF-1. • Co-culture system suppresses inflammatory genes expression. • Co-culture system improves cell proliferation. • Exogenous IGF-1 inhibits inflammatory activity in SNP-stimulated chondrocytes. - Abstract: Rheumatoid arthritis (RA) and osteoarthritis (OA) are primarily chronic inflammatory diseases. Mesenchymal stem cells (MSCs) have the ability to differentiate into cells of the mesodermal lineage, and to regulate immunomodulatory activity. Specifically, MSCs have been shown to secrete insulin-like growth factor 1 (IGF-1). The purpose of the present study was to examine the inhibitory effects on inflammatory activity from a co-culture of human synovium-derived mesenchymal stem cells (hSDMSCs) and sodium nitroprusside (SNP)-stimulated chondrocytes. First, chondrocytes were treated with SNP to generate an in vitro model of RA or OA. Next, the co-culture of hSDMSCs with SNP-stimulated chondrocytes reduced inflammatory cytokine secretion, inhibited expression of inflammation activity-related genes, generated IGF-1 secretion, and increased the chondrocyte proliferation rate. To evaluate the effect of IGF-1 on inhibition of inflammation, chondrocytes pre-treated with IGF-1 were treated with SNP, and then the production of inflammatory cytokines was analyzed. Treatment with IGF-1 was shown to significantly reduce inflammatory cytokine secretion in SNP-stimulated chondrocytes. Our results suggest that hSDMSCs offer a new strategy to promote cell-based cartilage regeneration in RA or OA

  4. Co-culture with human synovium-derived mesenchymal stem cells inhibits inflammatory activity and increases cell proliferation of sodium nitroprusside-stimulated chondrocytes

    Energy Technology Data Exchange (ETDEWEB)

    Ryu, Jae-Sung; Jung, Yeon-Hwa; Cho, Mi-Young; Yeo, Jee Eun; Choi, Yun-Jin; Kim, Yong Il; Koh, Yong-Gon, E-mail: yonseranglab@daum.net

    2014-05-16

    Highlights: • Co-culture of hSDMSCs with SNP-stimulated chondrocytes improves anti-inflammation. • Co-culture system produces IGF-1. • Co-culture system suppresses inflammatory genes expression. • Co-culture system improves cell proliferation. • Exogenous IGF-1 inhibits inflammatory activity in SNP-stimulated chondrocytes. - Abstract: Rheumatoid arthritis (RA) and osteoarthritis (OA) are primarily chronic inflammatory diseases. Mesenchymal stem cells (MSCs) have the ability to differentiate into cells of the mesodermal lineage, and to regulate immunomodulatory activity. Specifically, MSCs have been shown to secrete insulin-like growth factor 1 (IGF-1). The purpose of the present study was to examine the inhibitory effects on inflammatory activity from a co-culture of human synovium-derived mesenchymal stem cells (hSDMSCs) and sodium nitroprusside (SNP)-stimulated chondrocytes. First, chondrocytes were treated with SNP to generate an in vitro model of RA or OA. Next, the co-culture of hSDMSCs with SNP-stimulated chondrocytes reduced inflammatory cytokine secretion, inhibited expression of inflammation activity-related genes, generated IGF-1 secretion, and increased the chondrocyte proliferation rate. To evaluate the effect of IGF-1 on inhibition of inflammation, chondrocytes pre-treated with IGF-1 were treated with SNP, and then the production of inflammatory cytokines was analyzed. Treatment with IGF-1 was shown to significantly reduce inflammatory cytokine secretion in SNP-stimulated chondrocytes. Our results suggest that hSDMSCs offer a new strategy to promote cell-based cartilage regeneration in RA or OA.

  5. β-Elemonic acid inhibits the cell proliferation of human lung adenocarcinoma A549 cells: The role of MAPK, ROS activation and glutathione depletion.

    Science.gov (United States)

    Wu, Tsu-Tuan; Lu, Chien-Lin; Lin, Hen-I; Chen, Bing-Fang; Jow, Guey-Mei

    2016-01-01

    β-elemonic acid, a known triterpene, exhibits anti-inflammatory effects, yet research on the pharmacological effects of β-elemonic acid is rare. We investigated the anticancer effects and the related molecular mechanisms of β-elemonic acid on human non-small cell lung cancer (NSCLC) A549 cells. The effects of β-elemonic acid on the growth of A549 cells were studied using a 3-(4,5)-2,5-diphenyltetrazolium bromide (MTT) assay. Apoptosis was detected using Annexin V staining. The effect of β-elemonic acid on the cell cycle of A549 cells was assessed using the propidium iodide method. The change in reactive oxygen species (ROS) was detected using a dichlorodihydrofluorescein diacetate (DCFH-DA) assay with microscopic examination. The expression levels of Bcl-2 family proteins, mitogen-activated protein kinase (MAPK) family proteins and cyclooxygenase 2 (COX-2) were detected using western blot analysis. Our data revealed that β-elemonic acid strongly induced human A549 lung cancer cell death in a dose- and time-dependent manner as determined by the MTT assay. β-elemonic acid-induced cell death was considered to be apoptotic when the phosphatidylserine exposure was observed using Annexin V staining. The death of human A549 lung cancer cells was caused by apoptosis induced by activation of ROS activity, increase in the sub-G1 proportion, downregulation of Bcl-2 expression, upregulation of Bax expression and inhibition of the MAPK signaling pathways. These results clearly demonstrated that β-elemonic acid inhibits proliferation by inducing hypoploid cells and cell apoptosis. Moreover, the anticancer effects of β-elemonic acid were related to the MAPK signaling pathway, ROS activation and glutathione depletion in human A549 lung cancer cells.

  6. Increased renin production in mice with deletion of peroxisome proliferator-activated receptor-gamma in juxtaglomerular cells

    DEFF Research Database (Denmark)

    Desch, Michael; Schreiber, Andrea; Schweda, Frank;

    2010-01-01

    We recently found that endogenous (free fatty acids) and pharmacological (thiazolidinediones) agonists of nuclear receptor Peroxisome proliferator-activated receptor (PPAR)gamma stimulate renin transcription. In addition, the renin gene was identified as a direct target of PPARgamma. The mouse re...

  7. Effects of Ouabain on Proliferation of Human Endothelial Cells Correlate with Na+,K+-ATPase Activity and Intracellular Ratio of Na+ and K.

    Science.gov (United States)

    Tverskoi, A M; Sidorenko, S V; Klimanova, E A; Akimova, O A; Smolyaninova, L V; Lopina, O D; Orlov, S N

    2016-08-01

    Side-by-side with inhibition of the Na+,K+-ATPase ouabain and other cardiotonic steroids (CTS) can affect cell functions by mechanisms other than regulation of the intracellular Na+ and K+ ratio ([Na+]i/[K+]i). Thus, we compared the dose- and time-dependences of the effect of ouabain on intracellular [Na+]i/[K+]i ratio, Na+,K+-ATPase activity, and proliferation of human umbilical vein endothelial cells (HUVEC). Treatment of the cells with 1-3 nM ouabain for 24-72 h decreased the [Na+]i/[K+]i ratio and increased cell proliferation by 20-50%. We discovered that the same ouabain concentrations increased Na+,K+-ATPase activity by 25-30%, as measured by the rate of (86)Rb(+) influx. Higher ouabain concentrations inhibited Na+,K+-ATPase, increased [Na+]i/[K+]i ratio, suppressed cell growth, and caused cell death. When cells were treated with low ouabain concentrations for 48 or 72 h, a negative correlation between [Na+]i/[K+]i ratio and cell growth activation was observed. In cells treated with high ouabain concentrations for 24 h, the [Na+]i/[K+]i ratio correlated positively with proliferation inhibition. These data demonstrate that inhibition of HUVEC proliferation at high CTS concentrations correlates with dissipation of the Na+ and K+ concentration gradients, whereas cell growth stimulation by low CTS doses results from activation of Na+,K+-ATPase and decrease in the [Na+]i/[K+]i ratio.

  8. Increased renin production in mice with deletion of peroxisome proliferator-activated receptor-gamma in juxtaglomerular cells.

    Science.gov (United States)

    Desch, Michael; Schreiber, Andrea; Schweda, Frank; Madsen, Kirsten; Friis, Ulla G; Weatherford, Eric T; Sigmund, Curt D; Sequeira Lopez, Maria Luisa; Gomez, R Ariel; Todorov, Vladimir T

    2010-03-01

    We recently found that endogenous (free fatty acids) and pharmacological (thiazolidinediones) agonists of nuclear receptor Peroxisome proliferator-activated receptor (PPAR)gamma stimulate renin transcription. In addition, the renin gene was identified as a direct target of PPARgamma. The mouse renin gene is regulated by PPARgamma through a distal enhancer direct repeat closely related to consensus PPAR response element (PPRE). In vitro studies demonstrated that PPARgamma knockdown stimulated PPRE-driven transcription. These data predicted that deficiency of PPARgamma would upregulate mouse renin expression. Consistent with these observations knockdown of PPARgamma increased the transcription of a reporter gene driven by the mouse renin PPRE-like motif in vitro. To study the impact of PPARgamma on renin production in vivo, we used a cre/lox system to generate double-transgenic mice with disrupted PPARgamma locus in renin-producing juxtaglomerular (JG) cells of the kidney (RC-PPARgamma(fl/fl) mice). We provide evidence that PPARgamma expression was effectively reduced in JG cells of RC-PPARgamma(fl/fl) mice. Fluorescent immunohistochemistry showed stronger renin signal in RC-PPARgamma(fl/fl) than in littermate control RC-PPARgamma(wt/wt) mice. Renin mRNA levels and plasma renin concentration in RC-PPARgamma(fl/fl) mice were almost 2-fold higher than in littermate controls. Arterial blood pressure and pressure control of renal vascular resistance, which play decisive roles in the regulation of renin production were indistinguishable between RC-PPARgamma(wt/wt) and RC-PPARgamma(fl/fl) mice. These data demonstrate that the JG-specific PPARgamma deficiency results in increased mouse renin expression in vivo thus corroborating earlier in vitro results. PPARgamma appears to be a relevant transcription factor for the control of renin gene in JG cells.

  9. A combination of desmopressin and docetaxel inhibit cell proliferation and invasion mediated by urokinase-type plasminogen activator (uPA) in human prostate cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Sasaki, Hiroshi; Klotz, Laurence H. [Division of Urology, Sunnybrook Health Sciences Center, Toronto, ON (Canada); Sugar, Linda M. [Department of Pathology, Sunnybrook Health Sciences Center, Toronto, ON (Canada); Kiss, Alexander [Department of Research Design and Biostatistics, Institute for Clinical Evaluative Sciences, Sunnybrook Health Sciences Center, Toronto, ON (Canada); Venkateswaran, Vasundara, E-mail: vasundara.venkateswaran@sunnybrook.ca [Division of Urology, Sunnybrook Health Sciences Center, Toronto, ON (Canada)

    2015-08-28

    Background: This study was designed to assess the effectiveness of a combination treatment using both desmopressin and docetaxel in prostate cancer treatment. Desmopressin is a well-known synthetic analogue of the antidiuretic hormone vasopressin. It has recently been demonstrated to inhibit tumor progression and metastasis in in vivo models. Docetaxel is widely used for the treatment of castration resistant prostate cancer (CRPC) patients. However, durable responses have been uncommon to date. In this study, we investigated the anti-tumor effect of desmopressin in combination with docetaxel in vitro and in vivo. Methods: Two prostate cancer cells (PC3, LNCaP) were treated with different concentrations of desmopressin alone, docetaxel alone, and a combination of desmopressin and docetaxel. Cell proliferation was determined by MTS assay. The anti-invasive and anti-migration potential of desmopressin and in combination with docetaxel were examined by wound healing assay, migration chamber assay, and matrigel invasion assay. Results: The combination of desmopressin and docetaxel resulted in a significant inhibition of PC3 and LNCaP cell proliferation (p < 0.01). Additionally, cell migration and invasion were also inhibited by the combination when compared to that of either treatment alone in PC3 cells (p < 0.01). The anti-tumor effect of this combination treatment was associated with down-regulation of both urokinase-type plasminogen activator (uPA) and matrix metalloproteinase (MMP-2 and MMP-9) in PC3 cells. Conclusions: We are the first to elucidate the anti-tumor and anti-metastatic potential of desmopressin in combination with docetaxel in a prostate cancer model via the uPA-MMP pathway. Our finding could potentially contribute to the therapeutic profile of desmopressin and enhance the efficacy of docetaxel based treatment for CRPC. - Highlights: • Desmopressin inhibits cell proliferation in prostate cancer cells. • The expression of cyclin A and CDK2

  10. White tea extract induces apoptosis in non-small cell lung cancer cells: the role of peroxisome proliferator-activated receptor-{gamma} and 15-lipoxygenases.

    Science.gov (United States)

    Mao, Jenny T; Nie, Wen-Xian; Tsu, I-Hsien; Jin, Yu-Sheng; Rao, Jian Yu; Lu, Qing-Yi; Zhang, Zuo-Feng; Go, Vay Liang W; Serio, Kenneth J

    2010-09-01

    Emerging preclinical data suggests that tea possess anticarcinogenic and antimutagenic properties. We therefore hypothesize that white tea extract (WTE) is capable of favorably modulating apoptosis, a mechanism associated with lung tumorigenesis. We examined the effects of physiologically relevant doses of WTE on the induction of apoptosis in non-small cell lung cancer cell lines A549 (adenocarcinoma) and H520 (squamous cell carcinoma) cells. We further characterized the molecular mechanisms responsible for WTE-induced apoptosis, including the induction of peroxisome proliferator-activated receptor-gamma (PPAR-gamma) and the 15-lipoxygenase (15-LOX) signaling pathways. We found that WTE was effective in inducing apoptosis in both A549 and H520 cells, and inhibition of PPAR-gamma with GW9662 partially reversed WTE-induced apoptosis. We further show that WTE increased PPAR-gamma activation and mRNA expression, concomitantly increased 15(S)-hydroxy-eicosatetraenoic acid release, and upregulated 15-LOX-1 and 15-LOX-2 mRNA expression by A549 cells. Inhibition of 15-LOX with nordihydroguaiaretic acid (NGDA), as well as caffeic acid, abrogated WTE-induced PPAR-gamma activation and upregulation of PPAR-gamma mRNA expression in A549 cells. WTE also induced cyclin-dependent kinase inhibitor 1A mRNA expression and activated caspase-3. Inhibition of caspase-3 abrogated WTE-induced apoptosis. Our findings indicate that WTE is capable of inducing apoptosis in non-small cell lung cancer cell lines. The induction of apoptosis seems to be mediated, in part, through the upregulation of the PPAR-gamma and 15-LOX signaling pathways, with enhanced activation of caspase-3. Our findings support the future investigation of WTE as an antineoplastic and chemopreventive agent for lung cancer. PMID:20668019

  11. Wnt5a-Ror2 signaling in mesenchymal stem cells promotes proliferation of gastric cancer cells by activating CXCL16-CXCR6 axis.

    Science.gov (United States)

    Takiguchi, Gosuke; Nishita, Michiru; Kurita, Kana; Kakeji, Yoshihiro; Minami, Yasuhiro

    2016-03-01

    Wnt5a-Ror2 signaling has been shown to play important roles in promoting aggressiveness of various cancer cells in a cell-autonomous manner. However, little is known about its function in cancer-associated stromal cells, including mesenchymal stem cells (MSCs). Thus, we examined the role of Wnt5a-Ror2 signaling in bone marrow-derived MSCs in regulating proliferation of undifferentiated gastric cancer cells. Coculture of a gastric cancer cell line, MKN45, with MSCs either directly or indirectly promotes proliferation of MKN45 cells, and suppressed expression of Ror2 in MSCs prior to coculture inhibits enhanced proliferation of MKN45 cells. In addition, conditioned media from MSCs, treated with control siRNA, but not siRNAs against Ror2, can enhance proliferation of MKN45 cells. Interestingly, it was found that expression of CXCL16 in MSCs is augmented by Wnt5a-Ror2 signaling, and that recombinant chemokine (C-X-C motif) ligand (CXCL)16 protein can enhance proliferation of MKN45 cells in the absence of MSCs. In fact, suppressed expression of CXCL16 in MSCs or an addition of a neutralizing antibody against CXCL16 fails to promote proliferation of MKN45 cells in either direct or indirect coculture with MSCs. Importantly, we show that MKN45 cells express chemokine (C-X-C motif) receptor (CXCR)6, a receptor for CXCL16, and that suppressed expression of CXCR6 in MKN45 cells results in a failure of its enhanced proliferation in either direct or indirect coculture with MSCs. These findings indicate that Wnt5a-Ror2 signaling enhances expression of CXCL16 in MSCs and, as a result, enhanced secretion of CXCL16 from MSCs might act on CXCR6 expressed on MKN45, leading to the promotion of its proliferation. PMID:26708384

  12. Mutation of isocitrate dehydrogenase 1 induces glioma cell proliferation via nuclear factor-κB activation in a hypoxia-inducible factor 1-α dependent manner.

    Science.gov (United States)

    Wang, Guoliang; Sai, Ke; Gong, Fanghe; Yang, Qunying; Chen, Furong; Lin, Jian

    2014-05-01

    Recently, mutations of the isocitrate dehydrogenase (IDH) 1 gene, which specifically occur in the majority of low-grade and secondary high-grade gliomas, have drawn particular attention of neuro-oncologists. Mutations of the IDH1 gene have been proposed to have significant roles in the tumorigenesis, progression and prognosis of gliomas. However, the molecular mechanism of the role of IDH1 mutants in gliomagenesis remains to be elucidated. The present study, showed that forced expression of an IDH1 mutant, of which the 132th amino acid residue arginine is substituted by histidine (IDH1R132H), promoted cell proliferation in cultured cells, while wild-type IDH1 overexpression had no effect on cell proliferation. Consistent with previous studies, it was also observed that expression of hypoxia-inducible factor 1-α (HIF1-α) was upregulated in IDH1R132H expressing cells with the induction of vascular endothelial growth factor (VEGF) expression. However, knockdown of VEGF via small RNA interference had no significant influence on the cell proliferation induced by overexpression of IDH1R132H, implying that another signaling pathway may be involved. Next, forced expression of IDH1R132H was found to activate nuclear factor-κB (NF-κB), since the inhibitory IκB protein (IκBα) was highly phosphorylated and the NF-κB p65 subunit was translocated into the nucleus. Notably, knockdown of HIF1-α significantly blocked NF-κB activation, which was induced by the overexpression of IDH1 mutants. In addition, expression of IDH1 mutants markedly induced the NF-κB target gene expression, including cyclin D1 and E and c-myc, which were involved in the regulation of cell proliferation. In conclusion, it was demonstrated that the IDH1 mutant activated NF-κB in a HIF1-α‑dependent manner and was involved in the regulation of cell proliferation.

  13. THE INCREASE IN PLASMINOGEN ACTIV ATOR INHIBITOR TYPE 1 EXPRESSION BY STIMULATION OF ACTIVATORS FOR PEROXISOME PROLIFERATOR ACTIVA TED RECEPTORS IN HUMAN ENDOTHELIAL CELLS

    Institute of Scientific and Technical Information of China (English)

    叶平; 胡晓晖; 赵亚力

    2002-01-01

    Objective.To investigate the effect of peroxisome proliferator activated receptors (PPARs) activators on plasminogen activator inhibitor type 1 (PAI 1) expression in human umbilical vein endothelial cells and the possible mechanism.Methods.Human umbilical vein endothelial cells (HUVECs) were obtained from normal fetus,and cultured conventionally.Then the HUVECs were exposed to test agents (linolenic acid,linoleic acid,oleic acid,stearic acid and prostaglandin J2 respectively) in varying concentrations with fresh media.RT- PCR and ELISA were applied to determine the expression of PPARs and PAI 1 in HUVECs.Results.PPAR α,PPAR δ and PPAR γ mRNA were detected by using RT PCR in HUVECs.Treatment of HUVECs with PPARα and PPAR γ activators- - linolenic acid,linoleic acid,oleic acid and prostaglandin J2 respectively,but not with stearic acid could augment PAI I mRNA expression and protein secretion in a concentration dependent manner.However,the mRNA expressions of 3 subclasses of PPAR with their activators in HUVECs were not changed compared with controls.Conclusion.HUVECs express PPARs.PPARs activators may increase PAI 1 expression in ECs,but the underlying mechanism remains unclear.Although PPARs expression was not enhanced after stimulated by their activators in ECs,the role of functionally active PPARs in regulating PAI 1 expression in ECs needs to be further investigated by using transient gene transfection assay.

  14. Dixdc1 targets CyclinD1 and p21 via PI3K pathway activation to promote Schwann cell proliferation after sciatic nerve crush.

    Science.gov (United States)

    Wu, Weijie; Liu, Qingqing; Liu, Yuxi; Yu, Zhaohui; Wang, Youhua

    2016-09-16

    Dixdc1 (DIX domain containing-1), the mammalian homolog of Ccd1 (Coiled-coil-Dishevelled-Axin1), is a protein containing a coiled-coil domain and a Dishevelled-Axin (DIX) domain. As a novel component of the Wnt pathway, Dixdc1 has been reported to be able to promote neural progenitor proliferation and neuronal differentiation via Wnt/β-catenin signaling. But there still remains something unknown about Dixdc1 distribution and functions in the lesion and regeneration of the peripheral nervous system (PNS), so we tried to investigate dynamic changes of Dixdc1 expression in a rat sciatic nerve crush (SNC) model in this study. First of all, we detected SNC-induced increased levels of Dixdc1 in Schwann cells and interestingly identified parallel expression of PCNA (proliferation cell nuclear antigen) with Dixdc1. Besides, we observed up-regulated Dixdc1 during the process of TNF-α-induced Schwann cell proliferation. Also, we discovered that Dixdc1 could promote G1-S phase transition accompanied with the up-regulation of CyclinD1 and down-regulation of p21. More importantly, enhanced effects of Dixdc1 on cell proliferation were confirmed to be associated with PI3K activation. Not only blocking of the PI3K but Dixdc1 knockdown led to significantly decreased ability for proliferation, as well as down-regulation of CyclinD1 and up-regulation of p21. In summary, these data demonstrated that Dixdc1 might participate in Schwann cell proliferation by targeting CyclinD1 and p21 at least partially through the PI3K/AKT activation. PMID:27521891

  15. MECHANISMS OF CELL RESISTANCE TO CYTOMEGALOVIRUS ARE CONNECTED WITH CELL PROLIFERATION STATE AND TRANSCRIPTION ACTIVITY OF LEUKOCYTE AND IMMUNE INTERFERON GENES

    Directory of Open Access Journals (Sweden)

    T. M. Sokolova

    2007-01-01

    Full Text Available Abstract. Cytomegalovirus (CMV infection in diploid human fibroblasts (HF and levels of cell resistance to this virus were shown to be in direct correlation with high α-interferon (IFNα gene activity and induction of IFNγ gene transcription. Regulation of IFNα mRNA transcription was revealed to be positively associated with cellular DNA synthesis. At the same time, activities of IFNβ and IFNγ genes were at the constantly low level and were not induced in DNA-synthetic phase (S-phase of the cells. Levels of IFNα mRNA synthesis are quite different for G0- vs S-phase-synchronized HF110044 cell cultures: appropriate values for dividing cells (S-phase proved to be 100-fold higher than in resting state (G0. The mode of CMV infection in resting HF-cell could be considered either as acute, or a productive one. On the contrary, proliferating cells exhibited lagging viral syntheses and delayed cell death. Arrest of CMV replication may be, to some extent, comparable with latent infectious state, being associated with high production of IFNα. Both basal and induced levels of IFNα mRNA in CMV-resistant adult human skin fibroblast cells (HSF-1608 were 10-fold higher than in human embryo lung cell line (HELF-977, which is highly sensitive to CMV. Moreover, a short-time induction of IFNγ genes was observed in resistant cells, whereas no such effect was noticed in highly sensitive cells. CMV reproduction in sensitive cell lines (HELF-977 and HELF-110044 partially inhibits IFNα mRNA transcription at the later stages of infection (24 to 48 hours. Thus, cellular resistance and control of CMV infection in diploid fibroblasts are associated predominantly with high transcription of IFNα gene, and with temporal induction of IFNγ gene. We did not reveal any participation of IFNβ genes in protection of human diploid fibroblasts from CMV.

  16. BAFF induces spleen CD4+ T cell proliferation by down-regulating phosphorylation of FOXO3A and activates cyclin D2 and D3 expression

    International Nuclear Information System (INIS)

    Highlights: ► Firstly analyze the mechanism of BAFF and anti-CD3 co-stimulation on purified mouse splenic CD4+ T cells. ► Carrying out siRNA technology to study FOXO3A protein function. ► Helpful to understand the T cell especially CD4+ T cell‘s role in immunological reaction. -- Abstract: The TNF ligand family member “B cell-activating factor belonging to the TNF family” (BAFF, also called BLyS, TALL-1, zTNF-4, and THANK) is an important survival factor for B and T cells. In this study, we show that BAFF is able to induce CD4+ spleen T cell proliferation when co-stimulated with anti-CD3. Expression of phosphorylated FOXO3A was notably down-regulated and cyclins D2 and D3 were up-regulated and higher in the CD4+ T cells when treated with BAFF and anti-CD3, as assessed by Western blotting. Furthermore, after FOXO3A was knocked down, expression of cyclin D1 was unchanged, compared with control group levels, but the expression of cyclins D2 and D3 increased, compared with the control group. In conclusion, our results suggest that BAFF induced CD4+ spleen T cell proliferation by down-regulating the phosphorylation of FOXO3A and then activating cyclin D2 and D3 expression, leading to CD4+ T cell proliferation.

  17. Effect of S-adenosyl-L-methionine (SAM), an allosteric activator of cystathionine-β-synthase (CBS) on colorectal cancer cell proliferation and bioenergetics in vitro.

    Science.gov (United States)

    Módis, Katalin; Coletta, Ciro; Asimakopoulou, Antonia; Szczesny, Bartosz; Chao, Celia; Papapetropoulos, Andreas; Hellmich, Mark R; Szabo, Csaba

    2014-09-15

    Recent data show that colon cancer cells selectively overexpress cystathionine-β-synthase (CBS), which produces hydrogen sulfide (H2S), to maintain cellular bioenergetics, support tumor growth and stimulate angiogenesis and vasorelaxation in the tumor microenvironment. The purpose of the current study was to investigate the effect of the allosteric CBS activator S-adenosyl-L-methionine (SAM) on the proliferation and bioenergetics of the CBS-expressing colon cancer cell line HCT116. The non-transformed, non-tumorigenic colon epithelial cell line NCM356 was used as control. For assessment of cell proliferation, the xCELLigence system was used. Bioenergetic function was measured by Extracellular Flux Analysis. Experiments using human recombinant CBS or HCT116 homogenates complemented the cell-based studies. SAM markedly enhanced CBS-mediated H2S production in vitro, especially when a combination of cysteine and homocysteine was used as substrates. Addition of SAM (0.1-3 mM) to HCT116 cells induced a concentration-dependent increase H2S production. SAM exerted time- and concentration-dependent modulatory effects on cell proliferation. At 0.1-1 mM SAM increased HCT116 proliferation between 0 and 12 h, while the highest SAM concentration (3 mM) inhibited proliferation. Over a longer time period (12-24 h), only the lowest concentration of SAM used (0.1 mM) stimulated cell proliferation; higher SAM concentrations produced a concentration-dependent inhibition. The short-term stimulatory effects of SAM were attenuated by the CBS inhibitor aminooxyacetic acid (AOAA) or by stable silencing of CBS. In contrast, the inhibitory effects of SAM on cell proliferation was unaffected by CBS inhibition or CBS silencing. In contrast to HCT116 cells, the lower rate of proliferation of the low-CBS expressor NCM356 cells was unaffected by SAM. Short-term (1 h) exposure of HCT116 cells to SAM induced a concentration-dependent increase in oxygen consumption and bioenergetic function at 0

  18. Senegenin promotes in vitro proliferation of human neural progenitor cells

    Institute of Scientific and Technical Information of China (English)

    Fang Shi; Zhigang Liang; Zixuan Guo; Ran Li; Fen Yu; Zhanjun Zhang; Xuan Wang; Xiaomin Wang

    2011-01-01

    Senegenin, an effective component of Polygala tenuifolia root extract, promotes proliferation and differentiation of neural progenitor cells in the hippocampus.However, the effects of senegenin on mesencephalon-derived neural progenitor cells remain poorly understood.Cells from a ventral mesencephalon neural progenitor cell line (ReNcell VM) were utilized as models for pharmaceutical screening.The effects of various senegenin concentrations on cell proliferation were analyzed,demonstrating that high senegenin concentrations (5, 10, 50, and 100 pmo/L), particularly 50 pmol/L, significantly promoted proliferation of ReNcell VM cells.In the mitogen-activated protein kinase signal transduction pathway, senegenin significantly increased phosphorylation levels of extracellular signal-regulated kinases.Moreover, cell proliferation was suppressed by extracellular signal-regulated kinase inhibitors.Results suggested that senegenin contributed to in vitro proliferation of human neural progenitor cells by upregulating phosphorylation of extracellular signal-regulated kinase.

  19. Impairments in cognition and neural precursor cell proliferation in mice expressing constitutively active glycogen synthase kinase-3

    OpenAIRE

    Marta ePardo; King, Margaret K.; EMMA ePEREZ-COSTAS; Miguel eMelendez-Ferro; Ana eMartinez; Eleonore eBeurel; Richard Scott Jope

    2015-01-01

    ABSTRACTBrain glycogen synthase kinase-3 (GSK3) is hyperactive in several neurological conditions that involve impairments in both cognition and neurogenesis. This raises the hypotheses that hyperactive GSK3 may directly contribute to impaired cognition, and that this may be related to deficiencies in neural precursor cells (NPC). To study the effects of hyperactive GSK3 in the absence of disease influences, we compared adult hippocampal NPC proliferation and performance in three cognitive ta...

  20. Activation of canonical Wnt signaling pathway promotes proliferation and self-renewal of rat hepatic oval cell line WB-F344 in vitro

    Institute of Scientific and Technical Information of China (English)

    Ying Zhang; Xin-Min Li; Fu-Kui Zhang; Bao-En Wang

    2008-01-01

    AIM:To investigate the effect of activation of canonical Wnt signaling pathway on the proliferation and differentiation of hepatic oval cells in vitro.METHODS:WB-F344 cells were treated with recombinant Wnt3a (20,40,80,160,200 ng/mL) in serum-free medium for 24 h.Cell proliferation was measured by Brdu incorporation analysis; untreated WB-F344 cells were taken as controls.After treatment with Wnt3a (160 ng/mL) for 24 h,subcellular localization and protein expression of β-catenin in WB-F344 cells treated and untreated with Wnt3a were examined by immunofluorescence staining and Western blot analysis.CyclinD1 mRNA expression was determined by semi-quantitative reverse-transcript polymerase chain reaction (RT-PCR).The mRNA levels of some phenotypic markers (AFP,CK-19,ALB) and two hepatic nuclear factors (HNF-4,HNF-d) were measured by RT-PCR.Expressions of CK-19 and AFP protein were detected by Western blot analysis.RESULTS:Wnt3a promoted proliferation of WB-F344 cells.Stimulation of WB-F344 cells with recombinant Wnt3a resulted in accumulation of the transcriptional activator β-catenin,together with its translocation into the nuclei,and up-regulated typical Wnt target gene CyclinD1.After 3 d of Wnt3a treatment in the absence of serum,WB-F344 cells retained their bipotential to express several specific phenotypic markers of hepatocytes and cholangiocytes,such as AFP and CK-19,following activation of the canonical Wnt signaling pathway.CONCLUSION:The canonical Wnt signaling pathway promotes proliferation and self-renewal of rat hepatic oval cells.

  1. JAK2V617F/STAT5 signaling pathway promotes cell proliferation through activation of Pituitary Tumor Transforming Gene 1 expression

    Energy Technology Data Exchange (ETDEWEB)

    Shen, Xu-Liang [Department of Hematology, Heping Hospital of Changzhi Medical College, Changzhi 046000 (China); Department of Hematology, Xiangya Hospital of Centre-South University, Changsha 410008 (China); Wei, Wu; Xu, Hong-Liang; Zhang, Mei-Xiang; Qin, Xiao-Qi; Shi, Wen-Zhi; Jiang, Zhi-Ping [Department of Hematology, Heping Hospital of Changzhi Medical College, Changzhi 046000 (China); Chen, Yi-Jian [Department of Hematology, The First Affiliated Hospital, GanNan Medical University, GanZhou 341000 (China); Chen, Fang-Ping, E-mail: xychenfp@2118.cn [Department of Hematology, Xiangya Hospital of Centre-South University, Changsha 410008 (China)

    2010-08-06

    Research highlights: {yields} AG490, a member of tyrosine kinase inhibitors, could inhibit the JAK2V617F/STAT5 signaling pathway in HEL cell which harbor JAK2V617F mutation. {yields} Inhibition of the JAK2V617F/STAT5 signaling pathway inhibited the growth of HEL cells. {yields} JAK2V617F mutation promotes cell proliferation through activation of PTTG1 expression. {yields} JAK2V617F/STAT5 signaling pathway regulate PTTG1 expression at transcriptional level. -- Abstract: Gain-of-function mutations of JAK2 play crucial roles in the development of myeloproliferative neoplasms; however, the underlying downstream events of this activated signaling pathway are not fully understood. Our experiment was designed and performed to address one aspect of this issue. Here we report that AG490, a potent JAK2V617F kinase inhibitor, effectively inhibits the proliferation of HEL cells. Interestingly, AG490 also decreases the expression of PTTG1, a possible target gene of the aberrant signaling pathway, in a dose- and time-dependent manner. Furthermore, the promoter activity analyses reveal that the inhibition of the PTTG1 expression is affected at the transcriptional level. Thus, our results suggest that the JAK2V617F/STAT5 signaling pathway promotes cell proliferation through the transcriptional activation of PTTG1.

  2. IL-1β-induced matrix metalloproteinase-13 is activated by a disintegrin and metalloprotease-28-regulated proliferation of human osteoblast-like cells

    Energy Technology Data Exchange (ETDEWEB)

    Ozeki, Nobuaki; Kawai, Rie; Yamaguchi, Hideyuki; Hiyama, Taiki; Kinoshita, Katsue; Hase, Naoko; Nakata, Kazuhiko [Department of Endodontics, School of Dentistry, Aichi Gakuin University, 2-11 Suemori-dori, Chikusa-ku, Nagoya, Aichi 464-8651 (Japan); Kondo, Ayami [Department of Medicinal Biochemistry, School of Pharmacy, Aichi Gakuin University, 1-100 Kusumoto, Chikusa-ku, Nagoya, Aichi 464-8650 (Japan); Mogi, Makio, E-mail: makio@dpc.agu.ac.jp [Department of Medicinal Biochemistry, School of Pharmacy, Aichi Gakuin University, 1-100 Kusumoto, Chikusa-ku, Nagoya, Aichi 464-8650 (Japan); Nakamura, Hiroshi [Department of Endodontics, School of Dentistry, Aichi Gakuin University, 2-11 Suemori-dori, Chikusa-ku, Nagoya, Aichi 464-8651 (Japan)

    2014-04-15

    We reported previously that matrix metalloproteinase (MMP)-13 accelerates bone remodeling in oral periradicular lesions, and indicated a potentially unique role for MMP-13 in wound healing and regeneration of alveolar bone. The ADAM (a disintegrin and metalloprotease) family is a set of multifunctional cell surface and secreted glycoproteins, of which ADAM-28 has been localized in bone and bone-like tissues. In this study, we show that interleukin (IL)-1β induces the expression of MMP-13 and ADAM-28 in homogeneous α7 integrin-positive human skeletal muscle stem cell (α7{sup +}hSMSC)-derived osteoblast-like (α7{sup +}hSMSC-OB) cells, and promotes proliferation while inhibiting apoptosis in these cells. At higher concentrations, however, IL-1β failed to induce the expression of these genes and caused an increase in apoptosis. We further employed ADAM-28 small interfering RNA (siRNA) to investigate whether IL-1β-induced MMP-13 expression is linked to this IL-1β-mediated changes in cell proliferation and apoptosis. Silencing ADAM-28 expression potently suppressed IL-1β-induced MMP-13 expression and activity, decreased cell proliferation and increased apoptosis in α7{sup +}hSMSC-OB cells. In contrast, MMP-13 siRNA had no effect on ADAM-28 expression, suggesting ADAM-28 regulates MMP-13. Exogenous MMP-13 induced α7{sup +}hSMSC-OB cell proliferation and could rescue ADAM-28 siRNA-induced apoptosis, and we found that proMMP-13 is partially cleaved into its active form by ADAM-28 in vitro. Overall, our results suggest that IL-1β-induced MMP-13 expression and changes in cell proliferation and apoptosis in α7{sup +}hSMSC-OB cells are regulated by ADAM-28. - Highlights: • IL-1β induces the MMP-13 and ADAM-28 expression in human osteoblast-like cells. • IL-1β-induced MMP-13 expression increases proliferation and decreased apoptosis. • MMP-13 expression induced by IL-1β is regulated by ADAM-28. • proMMP-13 appears to be cleaved into its active form via

  3. IL-1β-induced matrix metalloproteinase-13 is activated by a disintegrin and metalloprotease-28-regulated proliferation of human osteoblast-like cells

    International Nuclear Information System (INIS)

    We reported previously that matrix metalloproteinase (MMP)-13 accelerates bone remodeling in oral periradicular lesions, and indicated a potentially unique role for MMP-13 in wound healing and regeneration of alveolar bone. The ADAM (a disintegrin and metalloprotease) family is a set of multifunctional cell surface and secreted glycoproteins, of which ADAM-28 has been localized in bone and bone-like tissues. In this study, we show that interleukin (IL)-1β induces the expression of MMP-13 and ADAM-28 in homogeneous α7 integrin-positive human skeletal muscle stem cell (α7+hSMSC)-derived osteoblast-like (α7+hSMSC-OB) cells, and promotes proliferation while inhibiting apoptosis in these cells. At higher concentrations, however, IL-1β failed to induce the expression of these genes and caused an increase in apoptosis. We further employed ADAM-28 small interfering RNA (siRNA) to investigate whether IL-1β-induced MMP-13 expression is linked to this IL-1β-mediated changes in cell proliferation and apoptosis. Silencing ADAM-28 expression potently suppressed IL-1β-induced MMP-13 expression and activity, decreased cell proliferation and increased apoptosis in α7+hSMSC-OB cells. In contrast, MMP-13 siRNA had no effect on ADAM-28 expression, suggesting ADAM-28 regulates MMP-13. Exogenous MMP-13 induced α7+hSMSC-OB cell proliferation and could rescue ADAM-28 siRNA-induced apoptosis, and we found that proMMP-13 is partially cleaved into its active form by ADAM-28 in vitro. Overall, our results suggest that IL-1β-induced MMP-13 expression and changes in cell proliferation and apoptosis in α7+hSMSC-OB cells are regulated by ADAM-28. - Highlights: • IL-1β induces the MMP-13 and ADAM-28 expression in human osteoblast-like cells. • IL-1β-induced MMP-13 expression increases proliferation and decreased apoptosis. • MMP-13 expression induced by IL-1β is regulated by ADAM-28. • proMMP-13 appears to be cleaved into its active form via ADAM-28

  4. Effect of Blood Component Coatings of Enosseal Implants on Proliferation and Synthetic Activity of Human Osteoblasts and Cytokine Production of Peripheral Blood Mononuclear Cells

    Science.gov (United States)

    Hulejova, Hana; Bartova, Jirina; Riedel, Tomas; Pesakova, Vlasta

    2016-01-01

    The study monitored in vitro early response of connective tissue cells and immunocompetent cells to enosseal implant materials coated by different blood components (serum, activated plasma, and plasma/platelets) to evaluate human osteoblast proliferation and synthetic activity and inflammatory response presented as a cytokine profile of peripheral blood mononuclear cells (PBMCs) under conditions imitating the situation upon implantation. The cells were cultivated on coated Ti-plasma-sprayed (Ti-PS), Ti-etched (Ti-Etch), Ti-hydroxyapatite (Ti-HA), and ZrO2 surfaces. The plasma/platelets coating supported osteoblast proliferation only on osteoconductive Ti-HA and Ti-Etch whereas activated plasma enhanced proliferation on all surfaces. Differentiation (BAP) and IL-8 production remained unchanged or decreased irrespective of the coating and surface; only the serum and plasma/platelets-coated ZrO2 exhibited higher BAP and IL-8 expression. RANKL production increased on serum and activated plasma coatings. PBMCs produced especially cytokines playing role in inflammatory phase of wound healing, that is, IL-6, GRO-α, GRO, ENA-78, IL-8, GM-CSF, EGF, and MCP-1. Cytokine profiles were comparable for all tested surfaces; only ENA-78, IL-8, GM-CSF, and MCP-1 expression depended on materials and coatings. The activated plasma coating led to uniformed surfaces and represented a favorable treatment especially for bioinert Ti-PS and ZrO2 whereas all coatings had no distinctive effect on bioactive Ti-HA and Ti-Etch.

  5. The in vitro assessment of anti proliferation activity of crude diethyl ether extract of Dendrophthoe species against to myeloma culture cell

    Directory of Open Access Journals (Sweden)

    Mochamad Lazuardi

    2008-03-01

    Full Text Available Herb medicine have an active substances that can dissolved on polar, semi polar and non polar liquid extract. The methanol and ethyl acetate as a polar and semi polar extract liquid were used to study of herb medicine such as Dendrophthoe species. Diethyl ether as a non polar liquid extract was never use to study the Dendrophthoe species. The aim of this study was to investigate the anti proliferation activity of Dendrophthoe species to myeloma culture cells after extracted by non-polar extract solution (diethyl ether. The post test only control group design was used for this research. A thirty six of microtiterplates wells were used for myeloma culture cells in RPMI medium. The wells were devided placing in two groups: treatment groups and controls groups. Each three wells of six treatment subgroups added with 100 µl of 1.1; 5.5; 11; 22; 33 and 44 µg/ml crude diethyl ether extract series. A RPMI solution at similar method and volume were used as control substances. The cells were assessed by inverted microscope in 200x magnified two days after. The cells were quantified analyzed for anti proliferation activity by using 1:1 methylene blue solution. The results showed that started from 11.0 µg/ml of crude diethyl ether extract of Dendrophthoe species have been anti proliferation abilities of myeloma culture cells (p<0.05. In conclusion, actives substances of Dendrophthoe species where dissolved in non polar liquid as diethyl ether has anti proliferation activities to cancer cell in vitro.

  6. Strain activation of bovine aortic smooth muscle cell proliferation and alignment: study of strain dependency and the role of protein kinase A and C signaling pathways

    Science.gov (United States)

    Mills, I.; Cohen, C. R.; Kamal, K.; Li, G.; Shin, T.; Du, W.; Sumpio, B. E.

    1997-01-01

    Smooth muscle cell (SMC) phenotype can be altered by physical forces as demonstrated by cyclic strain-induced changes in proliferation, orientation, and secretion of macromolecules. However, the magnitude of strain required and the intracellular coupling pathways remain ill defined. To examine the strain requirements for SMC proliferation, we selectively seeded bovine aortic SMC either on the center or periphery of silastic membranes which were deformed with 150 mm Hg vacuum (0-7% center; 7-24% periphery). SMC located in either the center or peripheral regions showed enhanced proliferation compared to cells grown under the absence of cyclic strain. Moreover, SMC located in the center region demonstrated significantly (P protein kinase C (PKC) activity and enzyme translocation from the cytosol to a particulate fraction. Further study was conducted to examine the effect of strain magnitude on signaling, particularly protein kinase A (PKA) activity as well as cAMP response element (CRE) binding protein levels. We observed significantly (P protein levels in SMC located in the center as compared to the peripheral region. However, inhibition of PKA (with 10 microM Rp-cAMP) or PKC (with 5-20 ng/ml staurosporine) failed to alter either the strain-induced increase in SMC proliferation or alignment. These data characterize the strain determinants for activation of SMC proliferation and alignment. Although strain activated both the AC/cAMP/PKA and the PKC pathways in SMC, singular inhibition of PKA and PKC failed to prevent strain-induced alignment and proliferation, suggesting either their lack of involvement or the multifactorial nature of these responses.

  7. Targeting AMP-activated protein kinase in adipocytes to modulate obesity-related adipokine production associated with insulin resistance and breast cancer cell proliferation

    Directory of Open Access Journals (Sweden)

    Grisouard Jean

    2011-07-01

    Full Text Available Abstract Background Adipokines, e.g. TNFα, IL-6 and leptin increase insulin resistance, and consequent hyperinsulinaemia influences breast cancer progression. Beside its mitogenic effects, insulin may influence adipokine production from adipocyte stromal cells and paracrine enhancement of breast cancer cell growth. In contrast, adiponectin, another adipokine is protective against breast cancer cell proliferation and insulin resistance. AMP-activated protein kinase (AMPK activity has been found decreased in visceral adipose tissue of insulin-resistant patients. Lipopolysaccharides (LPS link systemic inflammation to high fat diet-induced insulin resistance. Modulation of LPS-induced adipokine production by metformin and AMPK activation might represent an alternative way to treat both, insulin resistance and breast cancer. Methods Human preadipocytes obtained from surgical biopsies were expanded and differentiated in vitro into adipocytes, and incubated with siRNA targeting AMPKalpha1 (72 h, LPS (24 h, 100 μg/ml and/or metformin (24 h, 1 mM followed by mRNA extraction and analyses. Additionally, the supernatant of preadipocytes or derived-adipocytes in culture for 24 h was used as conditioned media to evaluate MCF-7 breast cancer cell proliferation. Results Conditioned media from preadipocyte-derived adipocytes, but not from undifferentiated preadipocytes, increased MCF-7 cell proliferation (p Conclusions Adipocyte-secreted factors enhance breast cancer cell proliferation, while AMPK and metformin improve the LPS-induced adipokine imbalance. Possibly, AMPK activation may provide a new way not only to improve the obesity-related adipokine profile and insulin resistance, but also to prevent obesity-related breast cancer development and progression.

  8. Costimulation of resting B lymphocytes alters the IL-4-activated IRS2 signaling pathway in a STAT6 independent manner: implications for cell survival and proliferation

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    IL-4 is an important B cell survival and growth factor.IL-4 induced the tyrosine phosphorylation of IRS2 in resting B lymphocytes and in LPS- or CD40L-activated blasts.Phosphorylated IRS2 coprecipitated with the p85 subunit of PI 3' kinase in both resting and activated cells.By contrast,association of phosphorylated IRS2 with GRB2 was not detected in resting B cells after IL-4 treatment although both proteins were expressed.However,IL-4 induced association of IRS2 with GRB2 in B cell blasts.The pattern of IL-4-induced recruitment of p85 and GRB2 to IRS2 observed in B cells derived from STAT6 null mice was identical to that observed for normal mice.While IL-4 alone does not induce activation of MEK,a MEK1 inhibitor suppressed the IL-4-induced proliferative response of LPS-activated B cell blasts.These results demonstrate that costimulation of splenic B cells alters IL-4-induced signal transduction independent of STAT6 leading to proliferation.Furthermore,proliferation induced by IL-4 in LPS-activated blasts is dependent upon the MAP kinase pathway.

  9. Proliferation of osteoblast cells on nanotubes

    Institute of Scientific and Technical Information of China (English)

    F.WATARI; T.AKASAKA; Xiaoming LI; M.UO; A.YOKOYAMA

    2009-01-01

    Carbon nanotubes (CNT) have a unique structme and feature. In the present study, cell proliferation was performed on the scaffolds of single-walled CNTs (SWCNT), multiwalled CNTs (MWCNT), and on gra-phita, one of the representative isomorphs of pure carbon,for the sake of comparison. Scanning electron microscopy observation of the growth of osteoblast-like cells (Saps2) cultttred on CNTs showed the morphology fully developed for the whole direction, which is different from that extended to one direction on the usual scaffold. Numerous filopodia were grown from cell edge, extended far long and combined with the CNT meshwork. CNTs showed the affinity for collagen and proteins. Proliferated cell numbers are largest on SWCNTs, followed by MWCNTs, and are very low on graphite. This is in good agreement with the sequence in the results of the adsorbed amount of proteins and expression of alkaline phosphatase activity for these scaffolds. The adsorption of protains would be one of the most influential factors to make a contrast difference in cell attachment and proliferation between graphite and CNTs,both of which are isomorphs of carbon and composed of similar graphene sheet crystal structure. In addition, the nanosize meshwork structure with large porosity is another properly responsible for the excellent cell adhesion and growth on CNTs. CNTs could be the favorable materials for biomedical applications.CNTs with different structures and compositions have been synthesized and discovered [3]. Nanomaterials [2-9] and nanocomposites [10-15] may have various effects onliving organisms. In this study, a fundamental study for biomedical application, cell proliferation was performed on various nanotubes (biT), including (1) single-walled CNTs (SWCNT), (2) multiwalled CNTs (MWCNT), and on graphite, an isomorph of CNT, as a comparison.Figure 1 shows the schematic figures of two different crystal structures of carbon: graphite and CNT. Graphite has the layer-by-layer laminated

  10. Effect of All-Trans Retinoic Acid (ATRA on Viability, Proliferation, Activation and Lineage-Specific Transcription Factors of CD4+ T Cells

    Directory of Open Access Journals (Sweden)

    Katayoon Bidad

    2011-12-01

    Full Text Available All-trans retinoic acid (ATRA, as an active metabolite of vitamin A, has been shown to affect immune cells. This study was performed to evaluate the effect of ATRA on viability, proliferation, activation and lineage-specific transcription factors of CD4+ T cells. CD4+ T cells were  separated  from  heparinized  blood  of  healthy  donors  and  were  cultured  in conditions, some with, some without ATRA.Viability was assessed by PI  flowcytometry and proliferation was measured by MTT assay. CD69 expression was determined by flowcytometry as a measure of cell activation. Lineage-specific transcription  factors  (FOXP3,  RORγt  and  T-bet  were  examined  by intracellular staining and flowcytometry. High doses of ATRA (0.1-1 mM caused extensive cell death in both PBMCs and CD4+ T cells. Doses of ATRA equal to or lower than 10 µM did not  adversely affect cell viability and proliferation in comparison to  culture medium without ATRA.Doses of ATRA between 10 µM and 1nM significantly increased cell activation when compared  to  culture medium without  ATRA. ATRA could increase FOXP3+  and also FOXP3+RORγt+ T cells while it decreased RORγt+ and T-bet+ T cells. This study showed that doses of ATRA up to 10 µM are safe when using with CD4+  T cells in terms of cell viability, proliferation and activation.We  could  also  show  that  ATRA  diverts  the  human  immune  response  in  neutral conditions (without adding polarizing cytokines by increasing FOXP3+  cells and decreasing RORγt+  cells. ATRA could be regarded as a potential therapy in inflammatory conditions and autoimmunities.

  11. Loss of DDB1 Leads to Transcriptional p53 Pathway Activation in Proliferating Cells, Cell Cycle Deregulation, and Apoptosis in Zebrafish Embryos

    Science.gov (United States)

    Hu, Zhilian; Holzschuh, Jochen; Driever, Wolfgang

    2015-01-01

    DNA damage-binding protein 1 (DDB1) is a large subunit of the heterodimeric DDB complex that recognizes DNA lesions and initiates the nucleotide excision repair process. DDB1 is also a component of the CUL4 E3 ligase complex involved in a broad spectrum of cellular processes by targeted ubiquitination of key regulators. Functions of DDB1 in development have been addressed in several model organisms, however, are not fully understood so far. Here we report an ENU induced mutant ddb1 allele (ddb1m863) identified in zebrafish (Danio rerio), and analyze its effects on development. Zebrafish ddb1 is expressed broadly, both maternally and zygotically, with enhanced expression in proliferation zones. The (ddb1m863 mutant allele affects the splice acceptor site of exon 20, causing a splicing defect that results in truncation of the 1140 amino acid protein after residue 800, lacking part of the β-propeller domain BPC and the C-terminal helical domain CTD. ddb1m863 zygotic mutant embryos have a pleiotropic phenotype, including smaller and abnormally shaped brain, head skeleton, eyes, jaw, and branchial arches, as well as reduced dopaminergic neuron groups. However, early forming tissues develop normally in zygotic ddb1m863 mutant embryos, which may be due to maternal rescue. In ddb1m863 mutant embryos, pcna-expressing proliferating cell populations were reduced, concurrent with increased apoptosis. We also observed a concomitant strong up-regulation of transcripts of the tumor suppressor p53 (tp53) and the cell cycle inhibitor cdkn1a (p21a/bCIP1/WAF1) in proliferating tissues. In addition, transcription of cyclin genes ccna2 and ccnd1 was deregulated in ddb1m863 mutants. Reduction of p53 activity by anti-sense morpholinos alleviated the apoptotic phenotype in ddb1m863 mutants. These results imply that Ddb1 may be involved in maintaining proper cell cycle progression and viability of dividing cells during development through transcriptional mechanisms regulating genes

  12. Transcription factor activity of estrogen receptor α activation upon nonylphenol or bisphenol A treatment enhances the in vitro proliferation, invasion, and migration of neuroblastoma cells

    Directory of Open Access Journals (Sweden)

    Ma H

    2016-06-01

    Full Text Available Hongda Ma,1 Yao Yao,2 Changli Wang,1 Liyu Zhang,3 Long Cheng,4 Yiren Wang,5 Tao Wang,6 Erguang Liang,6 Hui Jia,1 Qinong Ye,4 Mingxiao Hou,1 Fan Feng11Department of Pharmacy, General Hospital of Shenyang Military Area Command, Shenyang, 2Department of Pharmacy, Women & Infants Hospital of Zhengzhou, Zhengzhou, 3Shaanxi Institute of Pediatric Disease, Xi’an Children’s Hospital, Xi’an, 4Institute of Biotechnology, Chinese Military Medical Science Academy, Beijing, 5School of Life Science, Shenyang Pharmaceutical University, Shenyang, 6Institute of Toxicology and Pharmacology, Chinese Military Medical Science Academy, Beijing, People’s Republic of ChinaAbstract: Many kinds of endocrine-disrupting chemicals (EDCs, for example, the environmental estrogens bisphenol A and nonylphenol, may regulate the activity of estrogen receptor α (ERα and therefore induce potential disruption of normal endocrine function. However, the involvement of EDCs in human cancers, especially in endocrine-related cancer neuroblastoma regulation, is not very clear. In this work, results showed that upon bisphenol A or nonylphenol treatment, the transcription factor activity of ERα was significantly increased in neuroblastoma cell line SH-SY5Y. Bisphenol A and nonylphenol could enhance ERα activity via recruiting it to the target gene promoter. Furthermore, treatment of bisphenol A and nonylphenol enhanced the in vitro proliferation, invasion, and migration ability of neuroblastoma cells. By investigating the role of EDC-induced ERα upregulation, our data extend the understanding of the function of EDCs and further suggest that ERα might be a potential therapeutic target in human neuroblastoma treatment.Keywords: neuroblastoma, endocrine-disrupting chemicals, environmental estrogens, bisphenol A and nonylphenol, proliferation and metastasis

  13. Propiconazole-enhanced hepatic cell proliferation is associated with dysregulation of the cholesterol biosynthesis pathway leading to activation of Erk1/2 through Ras farnesylation

    Energy Technology Data Exchange (ETDEWEB)

    Murphy, Lynea A.; Moore, Tanya; Nesnow, Stephen, E-mail: nesnow.stephen@epa.gov

    2012-04-15

    Propiconazole is a mouse hepatotumorigenic fungicide designed to inhibit CYP51, a key enzyme in the biosynthesis of ergosterol in fungi and is widely used in agriculture to prevent fungal growth. Metabolomic studies in mice revealed that propiconazole increased levels of hepatic cholesterol metabolites and bile acids, and transcriptomic studies revealed that genes within the cholesterol biosynthesis, cholesterol metabolism and bile acid biosyntheses pathways were up-regulated. Hepatic cell proliferation was also increased by propiconazole. AML12 immortalized hepatocytes were used to study propiconazole's effects on cell proliferation focusing on the dysregulation of cholesterol biosynthesis and resulting effects on Ras farnesylation and Erk1/2 activation as a primary pathway. Mevalonate, a key intermediate in the cholesterol biosynthesis pathway, increases cell proliferation in several cancer cell lines and tumors in vivo and serves as the precursor for isoprenoids (e.g. farnesyl pyrophosphate) which are crucial in the farnesylation of the Ras protein by farnesyl transferase. Farnesylation targets Ras to the cell membrane where it is involved in signal transduction, including the mitogen-activated protein kinase (MAPK) pathway. In our studies, mevalonic acid lactone (MVAL), a source of mevalonic acid, increased cell proliferation in AML12 cells which was reduced by farnesyl transferase inhibitors (L-744,832 or manumycin) or simvastatin, an HMG-CoA reductase inhibitor, indicating that this cell system responded to alterations in the cholesterol biosynthesis pathway. Cell proliferation in AML12 cells was increased by propiconazole which was reversed by co-incubation with L-744,832 or simvastatin. Increasing concentrations of exogenous cholesterol muted the proliferative effects of propiconazole and the inhibitory effects of L-733,832, results ascribed to reduced stimulation of the endogenous cholesterol biosynthesis pathway. Western blot analysis of subcellular

  14. Troglitazone, a peroxisome proliferator-activated receptor γ ligand, induces growth inhibition and apoptosis of HepG2 human liver cancer cells

    Institute of Scientific and Technical Information of China (English)

    Yan-Ming Zhou; Yin-Hao Wen; Xiao-Yan Kang; Hai-Hua Qian; Jia-Mei Yang; Zheng-Feng Yin

    2008-01-01

    AIM: To examine the effect of troglitazone, a peroxisome proliferator-activated receptor γ (PPARγ) ligand, on the proliferation and apoptosis of human liver cancer cells.METHODS: Liver cancer cell line HepG2 was cultured and treated with troglitazone. Cell proliferation was detected by 3-(4-,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay; apoptosis was detected by flow cytometry and terminal deoxynucleotidyl transferasemediated nick end labeling of DNA fragmentation sites (TUNEL) assay; and apoptosis-related protein was detected by immunocytochemistry and Western blotting.RESULTS: Troglitazone inhibited growth and induced apoptosis of HepG2 cells in a dose-dependent manner,and induced activation of caspase-3 expression.Troglitazone not only drove apoptosis-inhibiting factor survivin to translocate incompletely from the nucleus to the cytoplasm, but also inhibited expression of survivin,while it did not affect expression of apoptosis-promoting factor Bax.CONCLUSION: PPARγ ligands inhibit growth and induce apoptosis of liver cancer cells, and may have applications for the prevention and treatment of liver cancer.

  15. Influence of Polyphenol Extract from Evening Primrose (Oenothera Paradoxa Seeds on Proliferation of Caco-2 Cells and on Expression, Synthesis and Activity of Matrix Metalloproteinases and Their Inhibitors

    Directory of Open Access Journals (Sweden)

    Szewczyk Karolina

    2014-09-01

    Full Text Available Evening primrose (Oenothera paradoxa Hudziok seeds are a rich source of not only a valuable oil containing an essential fatty acid - ᵧ-linolenic acid (GLA - but also polyphenols which can be obtained from the biomass remaining after oil pressing. The aim of our studies was to evaluate the influence of a polyphenol extract from defatted seeds of evening primrose on human colorectal adenocarcinoma Caco-2 cell proliferation and matrix metalloproteinases (MMPs synthesis and activity. To assess the effect of evening primrose extract on Caco-2 cell proliferation, crystal violet staining and sulforhodamine B (SRB assays were used whereas mRNA expression and activity of MMPs were evaluated by RT-PCR and gelatin zymography.

  16. All-Trans Retinoic Acid Induces Proliferation, Survival, and Migration in A549 Lung Cancer Cells by Activating the ERK Signaling Pathway through a Transcription-Independent Mechanism

    Science.gov (United States)

    Quintero Barceinas, Reyna Sara; García-Regalado, Alejandro; Aréchaga-Ocampo, Elena; Villegas-Sepúlveda, Nicolás; González-De la Rosa, Claudia Haydée

    2015-01-01

    All-trans retinoic acid (ATRA) has been used as an antineoplastic because of its ability to promote proliferation, inhibition, and differentiation, primarily in leukemia; however, in other types of cancer, such as lung cancer, treatment with ATRA is restricted because not all the patients experience the same results. The ERK signaling pathway is dysregulated in cancer cells, including lung cancer, and this dysregulation promotes proliferation and cell invasion. In this study, we demonstrate that treatment with ATRA can activate the ERK signaling pathway by a transcription-independent mechanism through a signaling cascade that involves RARα and PI3K, promoting growth, survival, and migration in lung cancer cells. Until now, this mechanism was unknown in lung cancer cells. The inhibition of the ERK signaling pathway restores the beneficial effects of ATRA, reduces proliferation, increases apoptosis, and blocks the cell migration process in lung cancer cells. In conclusion, our results suggest that the combination of ATRA with ERK inhibitor in clinical trials for lung cancer is warranted. PMID:26557664

  17. Teaching Activities on Horizontal Nuclear Proliferation.

    Science.gov (United States)

    Zola, John

    1990-01-01

    Provides learning activities concerning the horizontal proliferation of nuclear weapons. Includes step-by-step directions for four activities: (1) the life cycle of nuclear weapons; (2) nuclear nonproliferation: pros and cons; (3) the nuclear power/nuclear weapons connection; and (4) managing nuclear proliferation. (NL)

  18. Pharmacological activation of CB2 receptors counteracts the deleterious effect of ethanol on cell proliferation in the main neurogenic zones of the adult rat brain

    Science.gov (United States)

    Rivera, Patricia; Blanco, Eduardo; Bindila, Laura; Alen, Francisco; Vargas, Antonio; Rubio, Leticia; Pavón, Francisco J.; Serrano, Antonia; Lutz, Beat; Rodríguez de Fonseca, Fernando; Suárez, Juan

    2015-01-01

    Chronic alcohol exposure reduces endocannabinoid activity and disrupts adult neurogenesis in rodents, which results in structural and functional alterations. Cannabinoid receptor agonists promote adult neural progenitor cell (NPC) proliferation. We evaluated the protective effects of the selective CB1 receptor agonist ACEA, the selective CB2 receptor agonist JWH133 and the fatty-acid amide-hydrolase (FAAH) inhibitor URB597, which enhances endocannabinoid receptor activity, on NPC proliferation in rats with forced consumption of ethanol (10%) or sucrose liquid diets for 2 weeks. We performed immunohistochemical and stereological analyses of cells expressing the mitotic phosphorylation of histone-3 (phospho-H3+) and the replicating cell DNA marker 5-bromo-2'-deoxyuridine (BrdU+) in the main neurogenic zones of adult brain: subgranular zone of dentate gyrus (SGZ), subventricular zone of lateral ventricles (SVZ) and hypothalamus. Animals were allowed ad libitum ethanol intake (7.3 ± 1.1 g/kg/day) after a controlled isocaloric pair-feeding period of sucrose and alcoholic diets. Alcohol intake reduced the number of BrdU+ cells in SGZ, SVZ, and hypothalamus. The treatments (URB597, ACEA, JWH133) exerted a differential increase in alcohol consumption over time, but JWH133 specifically counteracted the deleterious effect of ethanol on NPC proliferation in the SVZ and SGZ, and ACEA reversed this effect in the SGZ only. JWH133 also induced an increased number of BrdU+ cells expressing neuron-specific β3-tubulin in the SVZ and SGZ. These results indicated that the specific activation of CB2 receptors rescued alcohol-induced impaired NPC proliferation, which is a potential clinical interest for the risk of neural damage in alcohol dependence. PMID:26483633

  19. Long interspersed nucleotide acid element-1 ORF-1 protein promotes proliferation and invasion of human colorectal cancer LoVo cells through enhancing ETS-1 activity.

    Science.gov (United States)

    Li, M Y; Zhu, M; Feng, F; Cai, F Y; Fan, K C; Jiang, H; Wang, Z Q; Linghu, E Q

    2014-04-14

    The human proto-oncogene long interspersed nucleotide acid element-1 (LINE-1) open reading frame-1 protein (ORF-1p) is involved in the progress of several cancers. The transcription factor ETS-1 can mediate the transcription of some downstream genes that play specific roles in the regulation of cancerous cell invasion and metastasis. In this study, the effects of LINE-1 ORF-1p on ETS-1 activity and on the proliferation and invasion of human colorectal cancer LoVo cells were investigated. Results showed that the overexpression of LINE-1 ORF-1p enhanced the transcription of ETS-1 downstream genes and increased their protein levels, and downregulation of the LINE-1 ORF-1p level by small interfering RNA (siRNA) reduced the transcriptional activation of ETS-1. In addition, overexpression of LINE-1 ORF-1p promoted LoVo cell proliferation and anchor-independent growth, and a knockdown of the LINE-1 protein level by siRNA reduced the proliferation and anchor-independent growth ability of LoVo cells. In vivo data revealed that LINE-1 ORF-1p overexpression increased LoVo tumor growth in nude mice, whereas the siRNA knockdown of endogenous LINE-1 ORF-1p expression decreased LoVo cell growth in nude mice. Therefore, LINE- 1 ORF-1p could promote LoVo cell proliferation and invasion both in vitro and in vivo, indicating that it might be a useful molecular target for the treatment of human colorectal cancer.

  20. Extracts of proliferating and non-proliferating human cells display different base excision pathways and repair fidelity

    DEFF Research Database (Denmark)

    Akbari, Mansour; Pena Diaz, Javier; Andersen, Sonja;

    2009-01-01

    cells both had capacity for single- and two-nucleotide insertion BER activity. However, patch size longer than two nucleotides was only detected in extracts from proliferating cells. Relative to extracts from proliferating cells, extracts from non-proliferating cells had approximately two-fold higher...... concentration of POLbeta, which contributed to most of two-nucleotide insertion BER. In contrast, two-nucleotide insertion in extracts from proliferating cells was not dependent on POLbeta. BER fidelity was two- to three-fold lower in extracts from the non-proliferating compared with extracts of proliferating...... cells. Furthermore, although one-nucleotide deletion was the predominant type of repair error in both extracts, the pattern of repair errors was somewhat different. These results establish two-nucleotide patch BER as a distinct POLbeta-dependent mechanism in non-proliferating cells and demonstrate that...

  1. Enhanced Proliferation of Porcine Bone Marrow Mesenchymal Stem Cells Induced by Extracellular Calcium is Associated with the Activation of the Calcium-Sensing Receptor and ERK Signaling Pathway

    Directory of Open Access Journals (Sweden)

    Jingjing Ye

    2016-01-01

    Full Text Available Porcine bone marrow mesenchymal stem cells (pBMSCs have the potential for application in regenerative medicine. This study aims to investigate the effects of extracellular calcium (Ca2+o on pBMSCs proliferation and to explore the possible underlying mechanisms. The results demonstrated that 4 mM Ca2+o significantly promoted pBMSCs proliferation by reducing the G0/G1 phase cell percentage and by increasing the S phase cell proportion and the proliferation index of pBMSCs. Accordingly, Ca2+o stimulated the expression levels of proliferative genes such as cyclin A2, cyclin D1/3, cyclin E2, and PCNA and inhibited the expression of p21. In addition, Ca2+o resulted in a significant elevation of intracellular calcium and an increased ratio of p-ERK/ERK. However, inhibition of calcium-sensing receptor (CaSR by its antagonist NPS2143 abolished the aforementioned effects of Ca2+o. Moreover, Ca2+o-induced promotion of pBMSCs proliferation, the changes of proliferative genes expression levels, and the activation of ERK1/2 signaling pathway were effectively blocked by U0126, a selective ERK kinase inhibitor. In conclusion, our findings provided evidence that the enhanced pBMSCs proliferation in response to Ca2+o was associated with the activation of CaSR and ERK1/2 signaling pathway, which may be useful for the application of pBMSCs in future clinical studies aimed at tissue regeneration and repair.

  2. Cell proliferation alterations in Chlorella cells under stress conditions

    International Nuclear Information System (INIS)

    Very little is known about growth and proliferation in relation to the cell cycle regulation of algae. The lack of knowledge is even greater when referring to the potential toxic effects of pollutants on microalgal cell division. To assess the effect of terbutryn, a triazine herbicide, on the proliferation of the freshwater microalga Chlorella vulgaris three flow cytometric approaches were used: (1) in vivo cell division using 5-,6-carboxyfluorescein diacetate succinimidyl ester (CFSE) staining was measured, (2) the growth kinetics were determined by cytometric cell counting and (3) cell viability was evaluated with the membrane-impermeable double-stranded nucleic acid stain propidium iodide (PI). The results obtained in the growth kinetics study using CFSE to identify the microalgal cell progeny were consistent with those determined by cytometric cell counting. In all C. vulgaris cultures, each mother cell had undergone only one round of division through the 96 h of assay and the cell division occurred during the dark period. Cell division of the cultures exposed to the herbicide was asynchronous. Terbutryn altered the normal number of daughter cells (4 autospores) obtained from each mother cell. The number was only two in the cultures treated with 250 nM. The duration of the lag phase after the exposure to terbutryn could be dependent on the existence of a critical cell size to activate cytoplasmic division. Cell size, complexity and fluorescence of chlorophyll a of the microalgal cells presented a marked light/dark (day/night) cycle, except in the non-dividing 500 nM cultures, where terbutryn arrested cell division at the beginning of the cycle. Viability results showed that terbutryn has an algastatic effect in C. vulgaris cells at this concentration. The rapid and precise determination of cell proliferation by CFSE staining has allowed us to develop a model for assessing both the cell cycle of C. vulgaris and the in vivo effects of pollutants on growth and

  3. Cell proliferation alterations in Chlorella cells under stress conditions

    Energy Technology Data Exchange (ETDEWEB)

    Rioboo, Carmen [Laboratorio de Microbiologia, Facultad de Ciencias, Universidad de A Coruna, Campus da Zapateira s/n, 15008 A Coruna (Spain); O' Connor, Jose Enrique [Laboratorio de Citomica, Unidad Mixta de Investigacion CIPF-UVEG, Centro de Investigacion Principe Felipe, Avda. Autopista del Saler, 16, 46013 Valencia (Spain); Prado, Raquel; Herrero, Concepcion [Laboratorio de Microbiologia, Facultad de Ciencias, Universidad de A Coruna, Campus da Zapateira s/n, 15008 A Coruna (Spain); Cid, Angeles, E-mail: cid@udc.es [Laboratorio de Microbiologia, Facultad de Ciencias, Universidad de A Coruna, Campus da Zapateira s/n, 15008 A Coruna (Spain)

    2009-09-14

    Very little is known about growth and proliferation in relation to the cell cycle regulation of algae. The lack of knowledge is even greater when referring to the potential toxic effects of pollutants on microalgal cell division. To assess the effect of terbutryn, a triazine herbicide, on the proliferation of the freshwater microalga Chlorella vulgaris three flow cytometric approaches were used: (1) in vivo cell division using 5-,6-carboxyfluorescein diacetate succinimidyl ester (CFSE) staining was measured, (2) the growth kinetics were determined by cytometric cell counting and (3) cell viability was evaluated with the membrane-impermeable double-stranded nucleic acid stain propidium iodide (PI). The results obtained in the growth kinetics study using CFSE to identify the microalgal cell progeny were consistent with those determined by cytometric cell counting. In all C. vulgaris cultures, each mother cell had undergone only one round of division through the 96 h of assay and the cell division occurred during the dark period. Cell division of the cultures exposed to the herbicide was asynchronous. Terbutryn altered the normal number of daughter cells (4 autospores) obtained from each mother cell. The number was only two in the cultures treated with 250 nM. The duration of the lag phase after the exposure to terbutryn could be dependent on the existence of a critical cell size to activate cytoplasmic division. Cell size, complexity and fluorescence of chlorophyll a of the microalgal cells presented a marked light/dark (day/night) cycle, except in the non-dividing 500 nM cultures, where terbutryn arrested cell division at the beginning of the cycle. Viability results showed that terbutryn has an algastatic effect in C. vulgaris cells at this concentration. The rapid and precise determination of cell proliferation by CFSE staining has allowed us to develop a model for assessing both the cell cycle of C. vulgaris and the in vivo effects of pollutants on growth and

  4. BAFF induces spleen CD4{sup +} T cell proliferation by down-regulating phosphorylation of FOXO3A and activates cyclin D2 and D3 expression

    Energy Technology Data Exchange (ETDEWEB)

    Ji, Fang; Chen, Rongjing [Department of Orthodontics, Ninth People' s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Stomatology, Shanghai (China); Liu, Baojun [Laboratory of Lung, Inflammation and Cancers, Huashan Hospital, Fudan University, Shanghai (China); Zhang, Xiaoping [Department of Nuclear Medicine, Shanghai 10th People' s Hospital, Tongji University School of Medicine, Shanghai 200072 (China); Han, Junli; Wang, Haining [Department of General Dentistry, Ninth People' s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Stomatology, Shanghai (China); Shen, Gang [Department of Orthodontics, Ninth People' s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Stomatology, Shanghai (China); Tao, Jiang, E-mail: taojiang2012@yahoo.cn [Department of General Dentistry, Ninth People' s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Stomatology, Shanghai (China)

    2012-09-07

    Highlights: Black-Right-Pointing-Pointer Firstly analyze the mechanism of BAFF and anti-CD3 co-stimulation on purified mouse splenic CD4{sup +} T cells. Black-Right-Pointing-Pointer Carrying out siRNA technology to study FOXO3A protein function. Black-Right-Pointing-Pointer Helpful to understand the T cell especially CD4{sup +} T cell's role in immunological reaction. -- Abstract: The TNF ligand family member 'B cell-activating factor belonging to the TNF family' (BAFF, also called BLyS, TALL-1, zTNF-4, and THANK) is an important survival factor for B and T cells. In this study, we show that BAFF is able to induce CD4{sup +} spleen T cell proliferation when co-stimulated with anti-CD3. Expression of phosphorylated FOXO3A was notably down-regulated and cyclins D2 and D3 were up-regulated and higher in the CD4{sup +} T cells when treated with BAFF and anti-CD3, as assessed by Western blotting. Furthermore, after FOXO3A was knocked down, expression of cyclin D1 was unchanged, compared with control group levels, but the expression of cyclins D2 and D3 increased, compared with the control group. In conclusion, our results suggest that BAFF induced CD4{sup +} spleen T cell proliferation by down-regulating the phosphorylation of FOXO3A and then activating cyclin D2 and D3 expression, leading to CD4{sup +} T cell proliferation.

  5. Fucose-containing sulfated polysaccharides from brown seaweeds inhibit proliferation of melanoma cells and induce apoptosis by activation of caspase-3 in vitro.

    Science.gov (United States)

    Ale, Marcel Tutor; Maruyama, Hiroko; Tamauchi, Hidekazu; Mikkelsen, Jørn D; Meyer, Anne S

    2011-12-01

    Fucose-containing sulfated polysaccharides (FCSPs) extracted from seaweeds, especially brown macro-algae, are known to possess essential bioactive properties, notably growth inhibitory effects on tumor cells. In this work, we conducted a series of in vitro studies to examine the influence of FCSPs products from Sargassumhenslowianum C. Agardh (FSAR) and Fucus vesiculosus (FVES), respectively, on proliferation of melanoma B16 cells and to investigate the underlying apoptosis promoting mechanisms. Cell viability analysis showed that both FCSPs products, i.e., FSAR and FVES, decreased the proliferation of the melanoma cells in a dose-response fashion, with FSAR being more potent at lower dosages, and FVES being relatively more anti-proliferative than FSAR at higher dosages. Flow cytometric analysis by Annexin V staining of the melanoma cells exposed to the FCSPs products confirmed that both FSAR and FVES induced apoptosis. The FCSPs-induced apoptosis was evidenced by loss of plasma membrane asymmetry and translocation of the cell membrane phospholipids and was accompanied by the activation of caspase-3. The FCSPs bioactivity is proposed to be attributable to distinct structural features of the FCSPs, particularly the presence of sulfated galactofucans (notably in S.henslowianum) and sulfated fucans (notably in F. vesiculosus). This study thus indicates that unfractionated FCSPs may exert bioactive effects on skin cancer cells via induction of apoptosis through cascades of reactions that involve activation of caspase-3.

  6. Loss of proliferation and antigen presentation activity following internalization of polydispersed carbon nanotubes by primary lung epithelial cells.

    Directory of Open Access Journals (Sweden)

    Mandavi Kumari

    Full Text Available Interactions between poly-dispersed acid functionalized single walled carbon nanotubes (AF-SWCNTs and primary lung epithelial (PLE cells were studied. Peritoneal macrophages (PMs, known phagocytic cells were used as positive controls in this study. Recovery of live cells from cultures of PLE cells and PMs was significantly reduced in the presence of AF-SWCNTs, in a time and dose dependent manner. Both PLE cells as well as PMs could take up fluorescence tagged AF-SWCNTs in a time dependent manner and this uptake was significantly blocked by cytochalasin D, an agent that blocks the activity of acto-myosin fibers and therefore the phagocytic activity of cells. Confocal microscopic studies confirmed that AF-SWCNTs were internalized by both PLE cells and PMs. Intra-trachially instilled AF-SWCNTs could also be taken up by lung epithelial cells as well as alveolar macrophages. Freshly isolated PLE cells had significant cell division activity and cell cycling studies indicated that treatment with AF-SWCNTs resulted in a marked reduction in S-phase of the cell cycle. In a previously standardized system to study BCG antigen presentation by PLE cells and PMs to sensitized T helper cells, AF-SWCNTs could significantly lower the antigen presentation ability of both cell types. These results show that mouse primary lung epithelial cells can efficiently internalize AF-SWCNTs and the uptake of nanotubes interfered with biological functions of PLE cells including their ability to present BCG antigens to sensitized T helper cells.

  7. Peroxiredoxins, oxidative stress, and cell proliferation.

    Science.gov (United States)

    Immenschuh, Stephan; Baumgart-Vogt, Eveline

    2005-01-01

    Peroxiredoxins (Prxs) are a family of multifunctional antioxidant thioredoxin-dependent peroxidases that have been identified in a large variety of organisms. The major functions of Prxs comprise cellular protection against oxidative stress, modulation of intracellular signaling cascades that apply hydrogen peroxide as a second messenger molecule, and regulation of cell proliferation. In the present review, we discuss pertinent findings on the protein structure, the cell- and tissue-specific distribution, as well as the subcellular localization of Prxs. A particular emphasis is put on Prx I, which is the most abundant and ubiquitously distributed member of the mammalian Prxs. Major transcriptional and posttranslational regulatory mechanisms and signaling pathways that control Prx gene expression and activity are summarized. The interaction of Prx I with the oncogene products c-Abl and c-Myc and the regulatory role of Prx I for cell proliferation and apoptosis are highlighted. Recent findings on phenotypical alterations of mouse models with targeted disruptions of Prx genes are discussed, confirming the physiological functions of Prxs for antioxidant cell and tissue protection along with an important role as tumor suppressors.

  8. Caspase activity and apoptotic signaling in proliferating C2C12 cells following cisplatin or A23187 exposure

    OpenAIRE

    Bloemberg, Darin; Quadrilatero, Joe

    2016-01-01

    Investigating cell death signaling using cell culture is commonly performed to examine the effects of novel pharmaceuticals or to further characterize discrete cellular signaling pathways. Here, we provide data regarding the cell death response to either cisplatin or A23187 in sub-confluent C2C12 cells, by utilizing several concentrations and incubation times for each chemical. These data include an assessment of the activation of the proteolytic enzymes caspase-3, caspase-8, caspase-9, calpa...

  9. Hydrogen sulfide promotes cell proliferation of oral cancer through activation of the COX2/AKT/ERK1/2 axis.

    Science.gov (United States)

    Zhang, Shuai; Bian, Huan; Li, Xiaoxu; Wu, Huanhuan; Bi, Qingwei; Yan, Yingbin; Wang, Yixiang

    2016-05-01

    Hydrogen sulfide, the third gaseous transmitter, is one of the main causes of halitosis in the oral cavity. It is generally considered as playing a deleterious role in many oral diseases including oral cancer. However, the regulatory mechanisms involved in the effects of hydrogen sulfide on oral cancer growth remain largely unknown. In the present study, we investigated the underlying mechanisms through CCK-8 assay, EdU incorporation, real-time PCR, western blot and pathway blockade assays. Our results showed that hydrogen sulfide promoted oral cancer cell proliferation through activation of the COX2, AKT and ERK1/2 pathways in a dose-dependent manner. Blocking any of the three above pathways inhibited hydrogen sulfide-induced oral cancer cell proliferation. Meanwhile, blockade of COX2 by niflumic acid downregulated NaHS-induced p-ERK and p-AKT expression. Inactivation of the AKT pathway by GSK690693 significantly decreased NaHS‑induced p-ERK1/2 expression, and inhibition of the ERK1/2 pathway by U0126 markedly increased NaHS-induced p-AKT expression. Either the AKT or ERK1/2 inhibitor did not significantly alter the COX2 expression level. Our data revealed, for the first time, that hydrogen sulfide promotes oral cancer cell proliferation through activation of the COX2/AKT/ERK1/2 axis, suggesting new potential targets to eliminate the effect of hydrogen sulfide on the development of oral cancer. PMID:26987083

  10. Metastasis-associated lung adenocarcinoma transcript 1 promotes the proliferation of chondro­sarcoma cell via activating Notch-1 signaling pathway

    Directory of Open Access Journals (Sweden)

    Xu FQ

    2016-04-01

    Full Text Available Fengqin Xu,1,* Zhi-qiang Zhang,2,* Yong-chao Fang,2 Xiao-lei Li,2 Yu Sun,2 Chuan-zhi Xiong,2 Lian-qi Yan,2 Qiang Wang2 1Department of Orthopaedics, Hongquan Hospital, 2Department of Orthopaedics, Subei People’s Hospital, Yangzhou, Jiangsu Province, People’s Republic of China *These authors contributed equally to this work Background: Metastasis-associated lung adenocarcinoma transcript 1 (MALAT-1 is identified to be overexpressed in several cancers. However, the role of MALAT-1 in chondrosarcoma is poorly understood.Methods: The expression of MALAT-1 and Notch-1 signaling pathway was detected in chondrosarcoma tissues and chondrosarcoma cells by quantitative real-time polymerase chain reaction (qRT-PCR and Western blot. 3-(4,5-Dimethyl-2-thiazolyl-2,5-diphenyl-2-H-tetrazolium bromide (MTT assay was performed to examine the cell viability of chondrosarcoma cells transfected with si-MALAT-1 or pcDNA-MALAT-1. Then the expression of Notch-1 signaling pathway was detected when MALAT-1 was upregulated or downregulated in chondrosarcoma cells. A subcutaneous chondrosarcoma cells xenograft model was used to confirm the effect of MALAT-1 on tumor growth in vivo.Results: We found the increased expression of MALAT-1 and Notch-1 signaling pathway in chondrosarcoma tissue and cells. MALAT-1 promoted the proliferation of chondrosarcoma cells. In addition, MALAT-1 activated the Notch-1 signaling pathway at posttranscriptional level in chondrosarcoma cells. Meanwhile, overexpression of Notch-1 reversed the effect of si-MALAT-1 on the proliferation of chondrosarcoma cells. Finally, we found that MALAT-1 promoted the tumor growth in a subcutaneous chondrosarcoma cells xenograft model, which confirmed the promoted effect of MALAT-1 on the tumor growth in vivo.Conclusion: Taken together, our study demonstrated that MALAT-1 promoted the proliferation of chondrosarcoma cell via activating Notch-1 signaling pathway. Keywords: MALAT-1, cell proliferation

  11. Activation of p21CIP1/WAF1 gene expression and inhibition of cell proliferation by overexpression of hepatocyte nuclear factor-4α

    International Nuclear Information System (INIS)

    The F9 murine embryonal carcinoma cell line provides an attractive system for studying epithelial differentiation and antiproliferative processes. We have recently established F9 cells expressing doxycycline-inducible hepatocyte nuclear factor (HNF)-4α and shown that HNF-4α triggers the gene expression of tight-junction molecules, occludin, claudin-6, and claudin-7, as well as formation of functional tight junctions and polarized epithelial morphology (Exp. Cell Res. 286, [2003] 288). Since these events were very similar to those induced by retinoids, we investigated whether HNF-4α, like retinoid receptors, was involved in the control of cell proliferation. We herein show that HNF-4α up-regulates expression of the p21 gene, but not the p15, p16, p18, p19, or p27 gene, in a p53-independent manner, and inhibits cell growth in F9 cells. Similar results were observed in rat lung endothelial cells, in which expression of HNF-4α is conditionally induced by doxycycline. Furthermore, we demonstrate, by reporter assay, that HNF-4α significantly elevates the transcriptional activity of the p21 promoter. Since, HNF-4α is expressed not only in the liver but also in organs containing epithelial cells, such as kidney, intestine, pancreas, and stomach, it might also play critical roles in the regulation of epithelial morphogenesis and proliferation in these organs

  12. Genetic evidence that intratumoral T-cell proliferation and activation are associated with recurrence and survival in patients with resected colorectal liver metastases.

    Science.gov (United States)

    Maker, Ajay V; Ito, Hiromichi; Mo, Qianxing; Weisenberg, Elliot; Qin, Li-Xuan; Turcotte, Simon; Maithel, Shishir; Shia, Jinru; Blumgart, Leslie; Fong, Yuman; Jarnagin, William R; DeMatteo, Ronald P; D'Angelica, Michael I

    2015-04-01

    Though immune responses correlate with prognosis in primary colorectal cancer, the role of tumor immunity in metastatic disease is less clear. We hypothesized that patient survival and tumor recurrence correlate with transcriptional evidence of lymphocyte proliferation/activation in resected colorectal cancer liver metastases (CRLM). Microarray gene analysis was performed on liver tumor specimens from 96 patients who underwent resection for CRLM. A Cox proportional hazards model identified genes associated with overall survival (OS) and recurrence-free survival (RFS). Conventional gene ontology (GO) enrichment analysis ranked biologically relevant processes. Survival probabilities of prioritized processes were assessed. Protein expression was validated with immunohistochemistry in an independent set of patients. GO analysis identified and ranked unique biologic processes that correlated with survival. Genes that specifically functioned in the biologic process of "T-cell proliferation" were significant predictors of OS (P = 0.01), and both "T-cell proliferation" and "activation" were highly associated with RFS (P ≤ 0.01). Analysis of genes in these GO categories identified increased TNFSF14/LIGHT expression to be most associated with improved OS and RFS (P ≤ 0.0006). Immunohistochemistry of an independent validation set of CRLM confirmed that both increased tumor-infiltrating lymphocytes (TIL) and higher LIGHT expression on TILs were associated with improved OS and RFS. Differential expression of genes involved in T-cell proliferation/activation was associated with survival outcomes in a large number of surgical patients who underwent resection of CRLM. These biologic functions determined by GO analysis of the tumor microenvironment have identified specific immune-related genes that may be involved in an antitumor immune response. PMID:25600439

  13. 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.

  14. Inhibition of DACH1 activity by short hairpin RNA represses cell proliferation and tumor invasion in pancreatic cancer.

    Science.gov (United States)

    Bu, Xiao-Na; Qiu, Chan; Wang, Chuan; Jiang, Zheng

    2016-08-01

    Cancer of the pancreas is one of the most lethal diseases worldwide. Better understanding of the molecular mechanisms involved in tumorigenesis is of great consequence to elevate the survival rate. Human Dachshund homologue 1 (DACH1) plays a controversial role in human malignancy progression with its expression being altered in a variety of cancers. Nevertheless, its functional roles and molecular mechanisms in pancreatic cancer remain unknown. The expression of DACH1 in pancreatic cancer cell lines and the ductal epithelial cells were evaluated both at mRNA and protein levels. Three pairs of siRNA targeting the DACH1 gene were designed and synthesized, double-stranded short hairpin RNA (shRNA) were annealed and inserted into pGenesil-1 vector, which was confirmed by enzymatic digestion and sequencing analyses. The successfully constructed recombinant plasmids were transfected into Capan-1 cells and our data indicated that knockdown of DACH1 gene expression showed strong correlation with repressing tumorigenesis. The proliferation of Capan-1 cells was significantly repressed as evaluated by CCK-8 and colony formation assays. Flow cymetry revealed that cell apoptosis was promoted in interference plasmid group compared with control groups (P0.05). Transwell assay validated the abilities of migration and invasion as being significantly reduced in pshRNA-DACH1 group. Furthermore, our study suggested that DACH1 expression regulates the pancreatic cancer cell apoptosis through interacting with Bcl-2 signaling axis, whereas it controls cell migration and invasion via epithelial-mesenchymal transition (EMT) process. PMID:27278537

  15. Effect of Blood Component Coatings of Enosseal Implants on Proliferation and Synthetic Activity of Human Osteoblasts and Cytokine Production of Peripheral Blood Mononuclear Cells

    Science.gov (United States)

    Hulejova, Hana; Bartova, Jirina; Riedel, Tomas; Pesakova, Vlasta

    2016-01-01

    The study monitored in vitro early response of connective tissue cells and immunocompetent cells to enosseal implant materials coated by different blood components (serum, activated plasma, and plasma/platelets) to evaluate human osteoblast proliferation and synthetic activity and inflammatory response presented as a cytokine profile of peripheral blood mononuclear cells (PBMCs) under conditions imitating the situation upon implantation. The cells were cultivated on coated Ti-plasma-sprayed (Ti-PS), Ti-etched (Ti-Etch), Ti-hydroxyapatite (Ti-HA), and ZrO2 surfaces. The plasma/platelets coating supported osteoblast proliferation only on osteoconductive Ti-HA and Ti-Etch whereas activated plasma enhanced proliferation on all surfaces. Differentiation (BAP) and IL-8 production remained unchanged or decreased irrespective of the coating and surface; only the serum and plasma/platelets-coated ZrO2 exhibited higher BAP and IL-8 expression. RANKL production increased on serum and activated plasma coatings. PBMCs produced especially cytokines playing role in inflammatory phase of wound healing, that is, IL-6, GRO-α, GRO, ENA-78, IL-8, GM-CSF, EGF, and MCP-1. Cytokine profiles were comparable for all tested surfaces; only ENA-78, IL-8, GM-CSF, and MCP-1 expression depended on materials and coatings. The activated plasma coating led to uniformed surfaces and represented a favorable treatment especially for bioinert Ti-PS and ZrO2 whereas all coatings had no distinctive effect on bioactive Ti-HA and Ti-Etch. PMID:27651560

  16. Nicotine as a mitogenic stimulus for pancreatic acinar cell proliferation

    Institute of Scientific and Technical Information of China (English)

    Parimal Chowdhury; Kodetthoor B Udupa

    2006-01-01

    Cell proliferation is an important process in life for growth of normal and cancer cells. The signal transduction pathways activated during this process are strictly regulated. This editorial focuses on the role of nicotine,a mitogen, in the induction of signaling pathways resulting in proliferation of pancreatic tumor cells and compares these events with those in normal acinar cells isolated from the rat pancreas. The data shows striking similarities between these two cellular systems.In addition, the editorial reviews very recent literature of the contribution of MAPK signaling in cell lines associated with human diseases. A prospective cellular model of nicotine induced activation of MAPK cascade is presented.

  17. Identification and characterization of novel activities from plant stem cell extracts regulating epidermal cell proliferation and homeostasis

    OpenAIRE

    di Martino, Orsola

    2015-01-01

    My PhD program included two phases, the first was carried out in the laboratory of Molecular Genetics, under the supervision of Professor Viola Calabrò, and the latter in the laboratory of Arterra Biosciene Srl. Arterra Bioscience is an Italian research-based biotech company with a strong know-how in biological science and an extensive experience in screening for the discovery of active molecules. The opportunity to join these two different scientific groups allows me to gain a more co...

  18. Pokemon enhances proliferation, cell cycle progression and anti-apoptosis activity of colorectal cancer independently of p14ARF-MDM2-p53 pathway.

    Science.gov (United States)

    Zhao, Yi; Yao, Yun-hong; Li, Li; An, Wei-fang; Chen, Hong-zen; Sun, Li-ping; Kang, Hai-xian; Wang, Sen; Hu, Xin-rong

    2014-12-01

    Pokemon has been showed to directly suppress p14(ARF) expression and also to overexpress in multiple cancers. However, p14(ARF)-MDM2-p53 pathway is usually aberrant in colorectal cancer (CRC). The aim is to confirm whether Pokemon plays a role in CRC and explore whether Pokemon works through p14(ARF)-MDM2-p53 pathway in CRC. Immunohistochemistry for Pokemon, p14(ARF) and Mtp53 protein was applied to 45 colorectal epitheliums (CREs), 42 colorectal adenomas (CRAs) and 66 CRCs. Pokemon was knocked down with RNAi technique in CRC cell line Lovo to detect mRNA expression of p14(ARF) with qRT-PCR, cell proliferation with CCK8 assay, and cell cycle and apoptosis with flowcytometry analysis. The protein expression rates were significantly higher in CRC (75.8%) than in CRE (22.2 %) or CRA (38.1%) for Pokemon and higher in CRC (53.0%) than in CRE (0) or CRA (4.8%) for Mtp53, but not significantly different in CRC (86.4 %) versus CRE (93.3%) or CRA (90.5 %) for p14(ARF). Higher expression rate of Pokemon was associated with lymph node metastasis and higher Duke's stage. After knockdown of Pokemon in Lovo cells, the mRNA level of p14(ARF) was not significantly changed, the cell proliferation ability was decreased by 20.6%, cell cycle was arrested by 55.7% in G0/G1 phase, and apoptosis rate was increased by 19.0%. Pokemon enhanced the oncogenesis of CRC by promoting proliferation, cell cycle progression and anti-apoptosis activity of CRC cells independently of p14(ARF)-MDM2-p53 pathway. This finding provided a novel idea for understanding and further studying the molecular mechanism of Pokemon on carcinogenesis of CRC. PMID:25367850

  19. Effects of calcium-activated chloride channels on proliferation of pulmonary artery smooth muscle cells in rats under chronic hypoxic condition

    Institute of Scientific and Technical Information of China (English)

    Zhao Yang; Zhenxiang Zhang; Yongjian Xu; Tao Wang; Dan Ma; Tao Ye

    2008-01-01

    Objective: To investigate the effects of calcium-activated chloride (C1Ca) channels on proliferation of pulmonary artery smooth muscle cells(PASMCs) in rats under chronic hypoxic condition. Methods:The cultured PASMCs were placed under normoxic and chronic hypoxic conditions:The cells were observed by light and electron microscope; The cell cycles were observed by flow-cytometry; Immunocytochemistry staining was used to detect the expressions of PCNA, c-los and c-jun of PASMCs; Cytoplasmic free Ca2+ con-centration ([Ca2+]) in PASMCs was investigated by fluorescent quantitation using fluorospectrophotometer. Results:The PASMCs were contractile phenotype under normoxic conditions. Observation by transmission electron microscope: In kytoplasm of contractile phenotype cells, myofilament bundles were abundant and the content of cell organs such as Golgi's bodies were rare. The PASMCs were synthetic phenotype under chronic hypoxic condition. There were inereased free ribosomes, dilated rough endoplasmic reticulums, highly developed Golgi complexes, decreased or disappeared thick filaments and dense body in kytoplasm of synthetic phenotype cells. After NFA and IAA-94, the situations were reversed The number of S4,GzM PASMCs were significantly increased in chronic hypoxic condition; The NFA and IAA-94 were shown to significantly decrease them from (28.6±1.0)% to (16.0±1.6)% and the number of G0G1 PASMCs significantly increased from (71.4 ±1.9)% to (83.9±1.6)% (P< 0.01). In chronic hypoxic conditions, the expression of proliferating cell nucleus antigen was significantly increased; The NFA and IAA-94 were shown to significantly decrease it from (81±6)% to (27±7)%(P<0.01). The expression of c-los and c-jun were significantly increased in-chronic hypoxic conditions; The NFA and IAA-94 were shown to significantly decrease them from 0.15 ± 0.02, 0.32 ± 0.05 to 0.05 ± 0.01, 0.12±0.05, respectively (P< 0.01); Under chronic hypoxic conditions, [Ca2+]. Was increased

  20. Inhibition of RUNX2 transcriptional activity blocks the proliferation, migration and invasion of epithelial ovarian carcinoma cells.

    Directory of Open Access Journals (Sweden)

    Zhi-Qiang Wang

    Full Text Available Previously, we have identified the RUNX2 gene as hypomethylated and overexpressed in post-chemotherapy (CT primary cultures derived from serous epithelial ovarian cancer (EOC patients, when compared to primary cultures derived from matched primary (prior to CT tumors. However, we found no differences in the RUNX2 methylation in primary EOC tumors and EOC omental metastases, suggesting that DNA methylation-based epigenetic mechanisms have no impact on RUNX2 expression in advanced (metastatic stage of the disease. Moreover, RUNX2 displayed significantly higher expression not only in metastatic tissue, but also in high-grade primary tumors and even in low malignant potential tumors. Knockdown of the RUNX2 expression in EOC cells led to a sharp decrease of cell proliferation and significantly inhibited EOC cell migration and invasion. Gene expression profiling and consecutive network and pathway analyses confirmed these findings, as various genes and pathways known previously to be implicated in ovarian tumorigenesis, including EOC tumor invasion and metastasis, were found to be downregulated upon RUNX2 suppression, while a number of pro-apoptotic genes and some EOC tumor suppressor genes were induced. Taken together, our data are indicative for a strong oncogenic potential of the RUNX2 gene in serous EOC progression and suggest that RUNX2 might be a novel EOC therapeutic target. Further studies are needed to more completely elucidate the functional implications of RUNX2 and other members of the RUNX gene family in ovarian tumorigenesis.

  1. Inhibition of RUNX2 transcriptional activity blocks the proliferation, migration and invasion of epithelial ovarian carcinoma cells.

    Science.gov (United States)

    Wang, Zhi-Qiang; Keita, Mamadou; Bachvarova, Magdalena; Gobeil, Stephane; Morin, Chantale; Plante, Marie; Gregoire, Jean; Renaud, Marie-Claude; Sebastianelli, Alexandra; Trinh, Xuan Bich; Bachvarov, Dimcho

    2013-01-01

    Previously, we have identified the RUNX2 gene as hypomethylated and overexpressed in post-chemotherapy (CT) primary cultures derived from serous epithelial ovarian cancer (EOC) patients, when compared to primary cultures derived from matched primary (prior to CT) tumors. However, we found no differences in the RUNX2 methylation in primary EOC tumors and EOC omental metastases, suggesting that DNA methylation-based epigenetic mechanisms have no impact on RUNX2 expression in advanced (metastatic) stage of the disease. Moreover, RUNX2 displayed significantly higher expression not only in metastatic tissue, but also in high-grade primary tumors and even in low malignant potential tumors. Knockdown of the RUNX2 expression in EOC cells led to a sharp decrease of cell proliferation and significantly inhibited EOC cell migration and invasion. Gene expression profiling and consecutive network and pathway analyses confirmed these findings, as various genes and pathways known previously to be implicated in ovarian tumorigenesis, including EOC tumor invasion and metastasis, were found to be downregulated upon RUNX2 suppression, while a number of pro-apoptotic genes and some EOC tumor suppressor genes were induced. Taken together, our data are indicative for a strong oncogenic potential of the RUNX2 gene in serous EOC progression and suggest that RUNX2 might be a novel EOC therapeutic target. Further studies are needed to more completely elucidate the functional implications of RUNX2 and other members of the RUNX gene family in ovarian tumorigenesis.

  2. HBx-related long non-coding RNA DBH-AS1 promotes cell proliferation and survival by activating MAPK signaling in hepatocellular carcinoma.

    Science.gov (United States)

    Huang, Jin-lan; Ren, Ting-yu; Cao, Shun-wang; Zheng, Shi-hao; Hu, Xiu-mei; Hu, Yan-wei; Lin, Li; Chen, Jing; Zheng, Lei; Wang, Qian

    2015-10-20

    Accumulating evidence supports an important role for the hepatitis B virus x protein (HBx) in the pathogenesis of hepatitis B virus (HBV)-induced hepatocellular carcinoma (HCC), but the underlying mechanisms are not entirely clear. Here, we identified a novel long noncoding RNA (lncRNA) DBH-AS1 involved in the HBx-mediated hepatocarcinogenesis. The levels of DBH-AS1 were positively correlated with hepatitis B surface antigen (HBsAg) and tumor size in HCC tissues. Functionally, transgenic expression of DBH-AS1 significantly enhanced cell proliferation and tumorigenesis, whereas short hairpin RNA knockdown of DBH-AS1 caused an inhibition of cell proliferation. Mechanistically, overexpression of DBH-AS1 induced cell cycle progression by accelerating G1/S and G2/M transition concomitantly with upregulation of CDK6, CCND1, CCNE1 and downregulation of p16, p21 and p27. We also found that enhanced DBH-AS1 expression inhibited serum starvation-induced apoptosis of HCC cells. In contrast, suppressed DBH-AS1 expression had opposite effects. Furthermore, DBH-AS1 was shown to activate MAPK pathway. We also provide evidence that DBH-AS1 could be significantly induced by HBx protein and markedly down-regulated by p53. Thus, we concluded that DBH-AS1 can be induced by HBx and inactivated by p53, and consequently promote cell proliferation and cell survival through activation of MAPK signaling in HCC. Our study suggests that DBH-AS1 acts as an oncogene for HCC. PMID:26393879

  3. Resveratrol suppresses IGF-1 induced human colon cancer cell proliferation and elevates apoptosis via suppression of IGF-1R/Wnt and activation of p53 signaling pathways

    Directory of Open Access Journals (Sweden)

    Radhakrishnan Sridhar

    2010-05-01

    Full Text Available Abstract Background Obesity is a global phenomenon and is associated with various types of cancer, including colon cancer. There is a growing interest for safe and effective bioactive compounds that suppress the risk for obesity-promoted colon cancer. Resveratrol (trans-3, 4', 5,-trihydroxystilbene, a stilbenoid found in the skin of red grapes and peanuts suppresses many types of cancers by regulating cell proliferation and apoptosis through a variety of mechanisms, however, resveratrol effects on obesity-promoted colon cancer are not clearly established. Methods We investigated the anti-proliferative effects of resveratrol on HT-29 and SW480 human colon cancer cells in the presence and absence of insulin like growth factor-1 (IGF-1; elevated during obesity and elucidated the mechanisms of action using IGF-1R siRNA in HT-29 cells which represents advanced colon carcinogenesis. Results Resveratrol (100-150 μM exhibited anti-proliferative properties in HT-29 cells even after IGF-1 exposure by arresting G0/G1-S phase cell cycle progression through p27 stimulation and cyclin D1 suppression. Treatment with resveratrol suppressed IGF-1R protein levels and concurrently attenuated the downstream Akt/Wnt signaling pathways that play a critical role in cell proliferation. Targeted suppression of IGF-1R using IGF-1R siRNA also affected these signaling pathways in a similar manner. Resveratrol treatment induced apoptosis by activating tumor suppressor p53 protein, whereas IGF-1R siRNA treatment did not affect apoptosis. Our data suggests that resveratrol not only suppresses cell proliferation by inhibiting IGF-1R and its downstream signaling pathways similar to that of IGF-1R siRNA but also enhances apoptosis via activation of the p53 pathway. Conclusions For the first time, we report that resveratrol suppresses colon cancer cell proliferation and elevates apoptosis even in the presence of IGF-1 via suppression of IGF-1R/Akt/Wnt signaling pathways and

  4. Laminin 5 regulates polycystic kidney cell proliferation and cyst formation.

    Science.gov (United States)

    Joly, Dominique; Berissi, Sophie; Bertrand, Amélie; Strehl, Laetitia; Patey, Natacha; Knebelmann, Bertrand

    2006-09-29

    Renal cyst formation is the hallmark of autosomal dominant polycystic kidney disease (ADPKD). ADPKD cyst-lining cells have an increased proliferation rate and are surrounded by an abnormal extracellular matrix (ECM). We have previously shown that Laminin 5 (Ln-5, a alpha(3)beta(3)gamma(2) trimer) is aberrantly expressed in the pericystic ECM of ADPKD kidneys. We report that ADPKD cells in primary cultures produce and secrete Ln-5 that is incorporated to the pericystic ECM in an in vitro model of cystogenesis. In monolayers, purified Ln-5 induces ERK activation and proliferation of ADPKD cells, whereas upon epidermal growth factor stimulation blocking endogenously produced Ln-5 with anti-gamma(2) chain antibody reduces the sustained ERK activation and inhibits proliferation. In three-dimensional gel culture, addition of purified Ln-5 stimulates cell proliferation and cyst formation, whereas blocking endogenous Ln-5 strongly inhibits cyst formation. Ligation of alpha(6)beta(4) integrin, a major Ln-5 receptor aberrantly expressed by ADPKD cells, induces beta(4) integrin phosphorylation, ERK activation, cell proliferation, and cyst formation. These findings indicate that Ln-5 is an important regulator of ADPKD cell proliferation and cystogenesis and suggest that Ln-5 gamma(2) chain and Ln-5-alpha(6)beta(4) integrin interaction both contribute to these phenotypic changes. PMID:16870608

  5. Erythropoietin -induced proliferation of gastric mucosal cells

    OpenAIRE

    Itoh, Kazuro; Sawasaki, Yoshio; Takeuchi, Kyoko; Kato, Shingo; Imai, Nobuhiro; Kato, Yoichiro; Shibata, Noriyuki; KOBAYASHI, MAKIO; Moriguchi, Yoshiyuki; Higuchi, Masato; Ishihata, Fumio; Sudoh, Yushi; Miura, Soichiro

    2006-01-01

    AIM: To analyze the localization of erythropoietin receptor on gastric specimens and characterize the effects of erythropoietin on the normal gastric epithelial proliferation using a porcine gastric epithelial cell culture model.

  6. N-methylhemeanthidine chloride, a novel Amaryllidaceae alkaloid, inhibits pancreatic cancer cell proliferation via down-regulating AKT activation

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Guoli; Yao, Guangmin; Zhan, Guanqun; Hu, Yufeng [Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei PR China (China); Yue, Ming [Hubei Key Laboratory of Drug Target Research and Pharmacodynamic Evaluation, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei (China); Cheng, Ling; Liu, Yaping; Ye, Qi [Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei PR China (China); Qing, Guoliang [Hubei Key Laboratory of Drug Target Research and Pharmacodynamic Evaluation, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei (China); Zhang, Yonghui, E-mail: zhangyh@mails.tjmu.edu.cn [Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei PR China (China); Liu, Hudan, E-mail: hudanliu@hust.edu.cn [Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei PR China (China)

    2014-11-01

    We previously reported the isolation of a novel Amaryllidaceae alkaloid, N-methylhemeanthidine chloride (NMHC), from Zephyranthes candida, which exhibits potent cytotoxicity in a spectrum of tumor cells. However, the mechanism of action remains unclear. Using multiple cell lines derived from human pancreatic cancer, one of the most mortal and refractory human malignancies, we further studied the NMHC-mediated cytotoxicity and found that it induced drastic cytotoxicity in pancreatic cancer cells whereas an insignificant effect on a noncancerous cell line. The NMHC-mediated growth inhibition was more severe than the first-line chemotherapeutic agent gemcitabine, leading to cell cycle arrest, apoptotic death and decreased glycolysis. NMHC exerted its function through down-regulating AKT activation, and the ectopic expression of activated AKT rescued the growth inhibition. Consistently, NMHC injections in a pancreatic cancer xenograft model manifested the anti-tumor effect in vivo. Engrafted tumor cells underwent AKT attenuation and apoptotic death upon treatments. As such, we here demonstrate the AKT inhibition may be one of the mechanisms by which NMHC decreases tumor cell survival rate in vitro and in vivo. Our data thereby suggest that NMHC holds great promise as a potent chemotherapeutic agent against pancreatic cancer and sheds new light on obtaining such agents from natural products toward therapeutic purposes. - Highlights: • N-methylhemeanthidine chloride (NMHC) is a novel Amaryllidaceae alkaloid. • NMHC exhibits potent anti-neoplastic activity. • NMHC leads to cell cycle arrest, apoptotic death and decreased metabolism. • NMHC down-regulates the AKT signaling pathway.

  7. p38 MAPK-Mediated Bmi-1 down-regulation and defective proliferation in ATM-deficient neural stem cells can be restored by Akt activation.

    Directory of Open Access Journals (Sweden)

    Jeesun Kim

    Full Text Available A-T (ataxia telangiectasia is a genetic disease caused by a mutation in the Atm (A-T mutated gene that leads to neurodegeneration. Despite an increase in the numbers of studies in this area in recent years, the mechanisms underlying neurodegeneration in human A-T are still poorly understood. Previous studies demonstrated that neural stem cells (NSCs isolated from the subventricular zone (SVZ of Atm(-/- mouse brains show defective self-renewal and proliferation, which is accompanied by activation of chronic p38 mitogen-activated protein kinase (MAPK and a lower level of the polycomb protein Bmi-1. However, the mechanism underlying Bmi-1 down-regulation and its relevance to defective proliferation in Atm(-/- NSCs remained unclear. Here, we show that over-expression of Bmi-1 increases self-renewal and proliferation of Atm(-/- NSCs to normal, indicating that defective proliferation in Atm(-/- NSCs is a consequence of down-regulation of Bmi-1. We also demonstrate that epidermal growth factor (EGF-induced Akt phosphorylation renders Bmi-1 resistant to the proteasomal degradation, leading to its stabilization and accumulation in the nucleus. However, inhibition of the Akt-dependent Bmi-1 stabilizing process by p38 MAPK signaling reduces the levels of Bmi-1. Treatment of the Atm(-/- NSCs with a specific p38 MAPK inhibitor SB203580 extended Bmi-1 posttranscriptional turnover and H2A ubiquitination in Atm(-/- NSCs. Our observations demonstrate the molecular basis underlying the impairment of self-renewal and proliferation in Atm(-/- NSCs through the p38 MAPK-Akt-Bmi-1-p21 signaling pathway.

  8. Pituitary adenylate cyclase-activating polypeptide (PACAP) and vasoactive intestinal peptide (VIP) regulate murine neural progenitor cell survival, proliferation, and differentiation.

    Science.gov (United States)

    Scharf, Eugene; May, Victor; Braas, Karen M; Shutz, Kristin C; Mao-Draayer, Yang

    2008-11-01

    Neural stem/progenitor cells (NPC) have gained wide interest over the last decade from their therapeutic potential, either through transplantation or endogenous replacement, after central nervous system (CNS) disease and damage. Whereas several growth factors and cytokines have been shown to promote NPC survival, proliferation, or differentiation, the identification of other regulators will provide much needed options for NPC self-renewal or lineage development. Although previous studies have shown that pituitary adenylate cyclase-activating polypeptide (PACAP)/vasoactive intestinal peptide (VIP) can regulate stem/progenitor cells, the responses appeared variable. To examine the direct roles of these peptides in NPCs, postnatal mouse NPC cultures were withdrawn from epidermal growth factor (EGF) and fibroblastic growth factor (FGF) and maintained under serum-free conditions in the presence or absence of PACAP27, PACAP38, or VIP. The NPCs expressed the PAC1(short)null receptor isoform, and the activation of these receptors decreased progenitor cell apoptosis more than 80% from TUNEL assays and facilitated proliferation more than fivefold from bromodeoxyuridine (BrdU) analyses. To evaluate cellular differentiation, replicate control and peptide-treated cultures were examined for cell fate marker protein and transcript expression. In contrast with previous work, PACAP peptides downregulated NPC differentiation, which appeared consistent with the proliferation status of the treated cells. Accordingly, these results demonstrate that PACAP signaling is trophic and can maintain NPCs in a multipotent state. With these attributes, PACAP may be able to promote endogenous NPC self-renewal in the adult CNS, which may be important for endogenous self-repair in disease and ageing processes.

  9. Ubiquitin carboxyl terminal hydrolase L1 negatively regulates TNF{alpha}-mediated vascular smooth muscle cell proliferation via suppressing ERK activation

    Energy Technology Data Exchange (ETDEWEB)

    Ichikawa, Tomonaga; Li, Jinqing; Dong, Xiaoyu; Potts, Jay D. [Department of Cell Biology and Anatomy, University of South Carolina School of Medicine, Columbia, SC 29208 (United States); Tang, Dong-Qi [Department of Pathology, Immunology, and Laboratory Medicine, University of Florida College of Medicine, Gainesville, FL 32610-0275 (United States); Li, Dong-Sheng, E-mail: dsli@yymc.edu.cn [Hubei Key Laboratory of Embryonic Stem Cell Research, Tai He Hospital, Yunyang Medical College, 32 S. Renmin Rd., Shiyan, Hubei 442000 (China); Cui, Taixing, E-mail: taixing.cui@uscmed.sc.edu [Department of Cell Biology and Anatomy, University of South Carolina School of Medicine, Columbia, SC 29208 (United States)

    2010-01-01

    Deubiquitinating enzymes (DUBs) appear to be critical regulators of a multitude of processes such as proliferation, apoptosis, differentiation, and inflammation. We have recently demonstrated that a DUB of ubiquitin carboxyl terminal hydrolase L1 (UCH-L1) inhibits vascular lesion formation via suppressing inflammatory responses in vasculature. However, the precise underlying mechanism remains to be defined. Herein, we report that a posttranscriptional up-regulation of UCH-L1 provides a negative feedback to tumor necrosis factor alpha (TNF{alpha})-mediated activation of extracellular signal-regulated kinases (ERK) and proliferation in vascular smooth muscle cells (VSMCs). In rat adult VSMCs, adenoviral over-expression of UCH-L1 inhibited TNF{alpha}-induced activation of ERK and DNA synthesis. In contrast, over-expression of UCH-L1 did not affect platelet derived growth factor (PDGF)-induced VSMC proliferation and activation of growth stimulating cascades including ERK. TNF{alpha} hardly altered UCH-L1 mRNA expression and stability; however, up-regulated UCH-L1 protein expression via increasing UCH-L1 translation. These results uncover a novel mechanism by which UCH-L1 suppresses vascular inflammation.

  10. Control mechanisms of cell proliferation in intestinal epithelium

    NARCIS (Netherlands)

    R.P.C. Rijke (Rudy)

    1977-01-01

    textabstractIn the adult organism some organs and tissues still contain proliferating and differentiating cells, whereas other organs only consist of non-dividing specialized cells. On the basis of their proliferative activity cell populations may be classified into three categories (135, 138,208).

  11. Cell proliferation and differentiation in chemical leukemogenesis

    Science.gov (United States)

    Irons, R. D.; Stillman, W. S.; Clarkson, T. W. (Principal Investigator)

    1993-01-01

    In tissues such as bone marrow with normally high rates of cell division, proliferation is tightly coordinated with cell differentiation. Survival, proliferation and differentiation of early hematopoietic progenitor cells depend on the growth factors, interleukin 3 (IL-3) and/or granulocyte-macrophage colony stimulating factor (GM-CSF) and their synergism with other cytokines. We provide evidence that a characteristic shared by a diverse group of compounds with demonstrated leukemogenic potential is the ability to act synergistically with GM-CSF. This results in an increase in recruitment of a resting population of hematopoietic progenitor cells normally unresponsive to the cytokine and a twofold increase in the size of the proliferating cell population normally regarded to be at risk of transformation in leukemogenesis. These findings support the possibility that transient alterations in hematopoietic progenitor cell differentiation may be an important factor in the early stages of development of leukemia secondary to chemical or drug exposure.

  12. Effect of Scopoletin on PC3 Cell Proliferation and Apoptosis

    Institute of Scientific and Technical Information of China (English)

    LiuXue-li; ZhangLiang; FuXin-lu; ChenKai; QianBo-chu

    2005-01-01

    To investigate the effect of scopoletin on cell proliferation and apoptosis of PC3 cells.Methods Cell growm curve,MMT assay,and acid phosphatase activity (ACP)were used to determine cell proliferation.Coomassie brillient blue assay was used to measure the content of protein in cells.Light microscope,transmission electronmicroscope,and fluorescence microscope were used to observe scopoletin-induced morphological changes. Apoptosis rate and cell cycle distribution were dctermined by flow cytometry.Results The IC50 of scopoletin for inhibiting PC3,PAA,and Hela cell proliferation was (157±25), (154±51),and (294±100)mg/L,respectively.Scopoletin induced a marked time and concentration-dependent inhibition of PC3 cell proliferation.Scopoletin reduced the protein content and decreased the ACP level in PC3 cells in a concentration dependent manlier.Cells treated by scopoletin showedtypical morphologic changes of apoptosis by light microscope,fluorescence microscope, and transmission electronmicroscope.Apoptosis rate was 0.3%,2.1%,9.3%and 35%for scopoletin 0,100,200,and 400 mg/L,respectively,and cells in G2 phase decreased markedly after being treated with scopoletin.Conclusion Scopoletin inhibited PC3 proliferation by inducing apoptosis of PC3 cells.

  13. Scaffold architecture and fibrin gels promote meniscal cell proliferation

    International Nuclear Information System (INIS)

    Stability of the knee relies on the meniscus, a complex connective tissue with poor healing ability. Current meniscal tissue engineering is inadequate, as the signals for increasing meniscal cell proliferation have not been established. In this study, collagen scaffold structure, isotropic or aligned, and fibrin gel addition were tested. Metabolic activity was promoted by fibrin addition. Cellular proliferation, however, was significantly increased by both aligned architectures and fibrin addition. None of the constructs impaired collagen type I production or triggered adverse inflammatory responses. It was demonstrated that both fibrin gel addition and optimized scaffold architecture effectively promote meniscal cell proliferation

  14. Scaffold architecture and fibrin gels promote meniscal cell proliferation

    Energy Technology Data Exchange (ETDEWEB)

    Pawelec, K. M., E-mail: pawelec.km@gmail.com, E-mail: jw626@cam.ac.uk; Best, S. M.; Cameron, R. E. [Cambridge Centre for Medical Materials, Materials Science and Metallurgy Department, University of Cambridge, Cambridge CB3 0FS (United Kingdom); Wardale, R. J., E-mail: pawelec.km@gmail.com, E-mail: jw626@cam.ac.uk [Division of Trauma and Orthopaedic Surgery, Department of Surgery, University of Cambridge, Cambridge CB2 2QQ (United Kingdom)

    2015-01-01

    Stability of the knee relies on the meniscus, a complex connective tissue with poor healing ability. Current meniscal tissue engineering is inadequate, as the signals for increasing meniscal cell proliferation have not been established. In this study, collagen scaffold structure, isotropic or aligned, and fibrin gel addition were tested. Metabolic activity was promoted by fibrin addition. Cellular proliferation, however, was significantly increased by both aligned architectures and fibrin addition. None of the constructs impaired collagen type I production or triggered adverse inflammatory responses. It was demonstrated that both fibrin gel addition and optimized scaffold architecture effectively promote meniscal cell proliferation.

  15. Invasion and Proliferation in Malignant Cells

    OpenAIRE

    Svensson Månsson, Sofie

    2006-01-01

    Two key events in the oncogenic process of tumor cells are to acquire uncontrolled proliferation and invasive properties. This allows the tumor to grow and invade beyond the tissue from which the tumor cells originate. We here specifically studied p16 and ERK1/2 with special focus on and the relation to proliferation and invasion in non-melanoma skin cancer and in breast cancer. In a model system of basal cell carcinoma, we observed that tumor cells changed phenotype from a highly prol...

  16. Cell proliferation potency is independent of FGF4 signaling in trophoblast stem cells derived from androgenetic embryos

    OpenAIRE

    Ogawa, Hidehiko; TAKYU, Ryuichi; MORIMOTO, Hiromu; TOEI, Shuntaro; SAKON, Hiroshi; GOTO, Shiori; MORIYA, SHOTA; Kono, Tomohiro

    2015-01-01

    We previously established trophoblast stem cells from mouse androgenetic embryos (AGTS cells). In this study, to further characterize AGTS cells, we compared cell proliferation activity between trophoblast stem (TS) cells and AGTS cells under fibroblast growth factor 4 (FGF4) signaling. TS cells continued to proliferate and maintained mitotic cell division in the presence of FGF4. After FGF4 deprivation, the cell proliferation stopped, the rate of M-phase cells decreased, and trophoblast gian...

  17. Dasatinib inhibits proliferation and activation of CD8+ T-lymphocytes by down-regulation of the T-cell receptor signaling

    OpenAIRE

    Fei, Fei

    2007-01-01

    The novel Src/Abl inhibitor dasatinib (BMS-354825) is a promising therapeutic agent with imatinib-resistant BCR-ABL mutations in patients with chronic myelogenous leukemia (CML) or Ph-positive acute lymphoblastic leukemia (ALL). However, little is known about its effects on T-cell function, especially for patients undergoing allogeneic transplantation for leukemia. Here, we demonstrate that dasatinib at a concentration of 5 nM to 250 nM inhibits the proliferation and activation of CD8+ T-lymp...

  18. Metformin inhibition of mTORC1 activation, DNA synthesis and proliferation in pancreatic cancer cells: Dependence on glucose concentration and role of AMPK

    International Nuclear Information System (INIS)

    Highlights: ► Metformin inhibits cancer cell growth but the mechanism(s) are not understood. ► We show that the potency of metformin is sharply dependent on glucose in the medium. ► AMPK activation was enhanced in cancer cells incubated in physiological glucose. ► Reciprocally, metformin potently inhibited mTORC1, DNA synthesis and proliferation. ► Metformin, at low concentrations, inhibited DNA synthesis through AMPK. -- Abstract: Metformin, a widely used anti-diabetic drug, is emerging as a potential anticancer agent but the mechanisms involved remain incompletely understood. Here, we demonstrate that the potency of metformin induced AMPK activation, as shown by the phosphorylation of its substrates acetyl-CoA carboxylase (ACC) at Ser79 and Raptor at Ser792, was dramatically enhanced in human pancreatic ductal adenocarcinoma (PDAC) cells PANC-1 and MiaPaCa-2 cultured in medium containing physiological concentrations of glucose (5 mM), as compared with parallel cultures in medium with glucose at 25 mM. In physiological glucose, metformin inhibited mTORC1 activation, DNA synthesis and proliferation of PDAC cells stimulated by crosstalk between G protein-coupled receptors and insulin/IGF signaling systems, at concentrations (0.05–0.1 mM) that were 10–100-fold lower than those used in most previous reports. Using siRNA-mediated knockdown of the α1 and α2 catalytic subunits of AMPK, we demonstrated that metformin, at low concentrations, inhibited DNA synthesis through an AMPK-dependent mechanism. Our results emphasize the importance of using medium containing physiological concentrations of glucose to elucidate the anticancer mechanism of action of metformin in pancreatic cancer cells and other cancer cell types.

  19. Metformin inhibition of mTORC1 activation, DNA synthesis and proliferation in pancreatic cancer cells: Dependence on glucose concentration and role of AMPK

    Energy Technology Data Exchange (ETDEWEB)

    Sinnett-Smith, James; Kisfalvi, Krisztina; Kui, Robert [Division of Digestive Diseases, Department of Medicine, CURE: Digestive Diseases Research Center, David Geffen School of Medicine and Molecular Biology Institute, University of California at Los Angeles, CA (United States); Rozengurt, Enrique, E-mail: erozengurt@mednet.ucla.edu [Division of Digestive Diseases, Department of Medicine, CURE: Digestive Diseases Research Center, David Geffen School of Medicine and Molecular Biology Institute, University of California at Los Angeles, CA (United States)

    2013-01-04

    Highlights: Black-Right-Pointing-Pointer Metformin inhibits cancer cell growth but the mechanism(s) are not understood. Black-Right-Pointing-Pointer We show that the potency of metformin is sharply dependent on glucose in the medium. Black-Right-Pointing-Pointer AMPK activation was enhanced in cancer cells incubated in physiological glucose. Black-Right-Pointing-Pointer Reciprocally, metformin potently inhibited mTORC1, DNA synthesis and proliferation. Black-Right-Pointing-Pointer Metformin, at low concentrations, inhibited DNA synthesis through AMPK. -- Abstract: Metformin, a widely used anti-diabetic drug, is emerging as a potential anticancer agent but the mechanisms involved remain incompletely understood. Here, we demonstrate that the potency of metformin induced AMPK activation, as shown by the phosphorylation of its substrates acetyl-CoA carboxylase (ACC) at Ser{sup 79} and Raptor at Ser{sup 792}, was dramatically enhanced in human pancreatic ductal adenocarcinoma (PDAC) cells PANC-1 and MiaPaCa-2 cultured in medium containing physiological concentrations of glucose (5 mM), as compared with parallel cultures in medium with glucose at 25 mM. In physiological glucose, metformin inhibited mTORC1 activation, DNA synthesis and proliferation of PDAC cells stimulated by crosstalk between G protein-coupled receptors and insulin/IGF signaling systems, at concentrations (0.05-0.1 mM) that were 10-100-fold lower than those used in most previous reports. Using siRNA-mediated knockdown of the {alpha}{sub 1} and {alpha}{sub 2} catalytic subunits of AMPK, we demonstrated that metformin, at low concentrations, inhibited DNA synthesis through an AMPK-dependent mechanism. Our results emphasize the importance of using medium containing physiological concentrations of glucose to elucidate the anticancer mechanism of action of metformin in pancreatic cancer cells and other cancer cell types.

  20. The role of 14-3-3{beta} in transcriptional activation of estrogen receptor {alpha} and its involvement in proliferation of breast cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yoonseo; Kim, Hyungjin; Jang, Sung-Wuk [School of Life Sciences and Biotechnology, Korea University, Seoul 136-701 (Korea, Republic of); Ko, Jesang, E-mail: jesangko@korea.ac.kr [School of Life Sciences and Biotechnology, Korea University, Seoul 136-701 (Korea, Republic of)

    2011-10-14

    Highlights: {yields} 14-3-3{beta} interacts with ER{alpha} and the interaction is Akt-dependent. {yields} 14-3-3{beta} regulates the transcriptional activity of ER{alpha} in a ligand-dependent manner. {yields} 14-3-3{beta} increases expressions of ER{alpha} target genes. {yields} 14-3-3{beta} increases breast cancer cell proliferation. -- Abstract: The estrogen receptor (ER) functions as a transcription factor that mediates the effects of estrogen. ER{alpha}, which plays a crucial role in the development and progression of breast cancer, is activated by estrogen binding, leading to receptor phosphorylation, dimerization, and recruitment of co-activators and chaperons to the estrogen-bound receptor complex. The 14-3-3 proteins bind to target proteins via phosphorylation and influence many cellular events by altering their subcellular localization or acting as a chaperone. However, regulation of ER{alpha} expression and transactivation by the 14-3-3 proteins has not been reported. We demonstrate that 14-3-3{beta} functions as a positive regulator of ER{alpha} through a direct protein-protein interaction in an estrogen-dependent manner. Ectopic expression of 14-3-3{beta} stimulated ER{alpha}-mediated transcriptional activity in MCF-7 breast cancer cells. Enhanced ER{alpha} transcriptional activity due to 14-3-3{beta} increased the expressions of the endogenous ER{alpha} target genes, leading to proliferation of breast cancer cells. We suggest that 14-3-3{beta} has oncogenic potential in breast cancer via binding to ER{alpha} and activation of the transcriptional activity of ER{alpha}.

  1. The fibrate decreases radiation sensitivity via peroxisome proliferator-activated receptor {alpha}-mediated superoxide dismutase induction in HeLa cells

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Xianguang; An, Zhengzhe; Song, Hye Jin; Kim, Won Dong; Park, Woo Yoon [Chungbuk National University College of Medicine, Cheongju (Korea, Republic of); Jang, Seong Soon [The Catholic University of Korea College of Medicine, Seoul (Korea, Republic of); Yu, Jae Ran [Konkuk University College of Medicine, Chungju (Korea, Republic of)

    2012-06-15

    The fibrates are ligands for peroxisome proliferator-activated receptor (PPAR) {alpha} and used clinically as hypolipidemic drugs. The fibrates are known to cause peroxisome proliferation, enhance superoxide dismutase (SOD) expression and catalase activity. The antioxidant actions of the fibrates may modify radiation sensitivity. Here, we investigated the change of the radiation sensitivity in two cervix cancer cell lines in combination with fenofi brate (FF). Activity and protein expression of SOD were measured according to the concentration of FF. The mRNA expressions were measured by using real time reverse-transcription polymerase chain reaction. Combined cytotoxic effect of FF and radiation was measured by using clonogenic assay. In HeLa cells total SOD activity was increased with increasing FF doses up to 30 {mu}M. In the other hand, the catalase activity was increased a little. As with activity the protein expression of SOD1 and SOD2 was increased with increasing doses of FF. The mRNAs of SOD1, SOD2, PPAR{alpha} and PPAR{gamma} were increased with increasing doses of FF. The reactive oxygen species (ROS) produced by radiation was decreased by preincubation with FF. The surviving fractions (SF) by combining FF and radiation was higher than those of radiation alone. In Me180 cells SOD and catalase activity were not increased with FF. Also, the mRNAs of SOD1, SOD2, and PPAR{alpha} were not increased with FF. However, the mRNA of PPAR{gamma} was increased with FF. FF can reduce radiation sensitivity by ROS scavenging via SOD induction in HeLa. SOD induction by FF is related with PPAR{alpha}.

  2. Kaposi's-sarcoma-associated-herpesvirus-activated dendritic cells promote HIV-1 trans-infection and suppress CD4{sup +} T cell proliferation

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Wan; Qin, Yan; Bai, Lei [Key Laboratory of Molecular Virology and Immunology, Institute Pasteur of Shanghai, the Chinese Academy of Sciences, Shanghai (China); Graduate School of the Chinese Academy of Sciences, Beijing (China); Lan, Ke [Key Laboratory of Molecular Virology and Immunology, Institute Pasteur of Shanghai, the Chinese Academy of Sciences, Shanghai (China); Wang, Jian-Hua, E-mail: Jh_wang@sibs.ac.cn [Key Laboratory of Molecular Virology and Immunology, Institute Pasteur of Shanghai, the Chinese Academy of Sciences, Shanghai (China)

    2013-06-05

    Infection of Kaposi's sarcoma-associated herpesvirus (KSHV) is commonly occurred in AIDS patients. KSHV and HIV-1 act cooperatively in regulating infection with each other and in human carcinogenesis. Dendritic cells (DCs), as the pivotal cells in host immunity, may be modulated by both viruses, for immunoevasion and dissemination, therefore, the interaction between DCs and each virus has been a prior focus for pathogenesis elucidation. Here, we assessed the potential effect of KSHV on DC–HIV-1 interaction. We found that KSHV stimulation could promote maturation of monocyte-derived DCs (MDDCs) and impaired the ability of MDDCs to drive proliferation of resting CD4{sup +} T cells, demonstrating the immunosuppression induced by KSHV. More importantly, KSHV-stimulated MDDCs could capture more HIV-1 and efficiently transferred these infectious viruses to Hut/CCR5 T cell line. Our results reveal the novel modulation of DC-mediated HIV-1 dissemination by KSHV, and highlight the importance of studying DC–HIV-1 interaction to elucidate HIV/AIDS pathogenesis. - Highlights: ► KSHV impaired the ability of MDDCs to drive proliferation of resting CD4{sup +} T cells. ► KSHV stimulation matured MDDCs and enhanced HIV-1 endocytosis. ► KSHV stimulated MDDCs increased ICAM-1 expression and tighten contact with T cells. ► KSHV-stimulated MDDCs promoted HIV-1 trans-infection of CD4{sup +} T cells.

  3. Kaposi's-sarcoma-associated-herpesvirus-activated dendritic cells promote HIV-1 trans-infection and suppress CD4+ T cell proliferation

    International Nuclear Information System (INIS)

    Infection of Kaposi's sarcoma-associated herpesvirus (KSHV) is commonly occurred in AIDS patients. KSHV and HIV-1 act cooperatively in regulating infection with each other and in human carcinogenesis. Dendritic cells (DCs), as the pivotal cells in host immunity, may be modulated by both viruses, for immunoevasion and dissemination, therefore, the interaction between DCs and each virus has been a prior focus for pathogenesis elucidation. Here, we assessed the potential effect of KSHV on DC–HIV-1 interaction. We found that KSHV stimulation could promote maturation of monocyte-derived DCs (MDDCs) and impaired the ability of MDDCs to drive proliferation of resting CD4+ T cells, demonstrating the immunosuppression induced by KSHV. More importantly, KSHV-stimulated MDDCs could capture more HIV-1 and efficiently transferred these infectious viruses to Hut/CCR5 T cell line. Our results reveal the novel modulation of DC-mediated HIV-1 dissemination by KSHV, and highlight the importance of studying DC–HIV-1 interaction to elucidate HIV/AIDS pathogenesis. - Highlights: ► KSHV impaired the ability of MDDCs to drive proliferation of resting CD4+ T cells. ► KSHV stimulation matured MDDCs and enhanced HIV-1 endocytosis. ► KSHV stimulated MDDCs increased ICAM-1 expression and tighten contact with T cells. ► KSHV-stimulated MDDCs promoted HIV-1 trans-infection of CD4+ T cells

  4. Leptin reverses corticosterone-induced inhibition of neural stem cell proliferation through activating the NR2B subunits of NMDA receptors

    Energy Technology Data Exchange (ETDEWEB)

    Shi, Wen-Zhu [Anesthesia and Operation Center, Hainan Branch of Chinese PLA General Hospital, Hainan 572013 (China); Anesthesia and Operation Center, Chinese PLA General Hospital, Beijing 100853 (China); Miao, Yu-Liang [Department of Anesthesiology, PLA No. 306 Hospital, Beijing 100101 (China); Guo, Wen-Zhi [Department of Anesthesiology, Beijing Military General Hospital of Chinese People’s Liberation Army, Beijing 100700 (China); Wu, Wei, E-mail: wwzwgk@163.com [Department of Head and Neck Surgery of Otolaryngology, PLA No. 306 Hospital, Beijing 100101 (China); Li, Bao-Wei [Department of Head and Neck Surgery of Otolaryngology, PLA No. 306 Hospital, Beijing 100101 (China); An, Li-Na [Department of Anesthesiology, Armed Police General Hospital, Beijing 100039 (China); Fang, Wei-Wu [Department of Anesthesiology, PLA No. 306 Hospital, Beijing 100101 (China); Mi, Wei-Dong, E-mail: elite2005gg@163.com [Anesthesia and Operation Center, Chinese PLA General Hospital, Beijing 100853 (China)

    2014-04-25

    Highlights: • Leptin promotes the proliferation of neural stem cells isolated from embryonic mouse hippocampus. • Leptin reverses corticosterone-induced inhibition of neural stem cell proliferation. • The effects of leptin are partially mediated by upregulating NR2B subunits. - Abstract: Corticosterone inhibits the proliferation of hippocampal neural stem cells (NSCs). The removal of corticosterone-induced inhibition of NSCs proliferation has been reported to contribute to neural regeneration. Leptin has been shown to regulate brain development, improve angiogenesis, and promote neural regeneration; however, its effects on corticosterone-induced inhibition of NSCs proliferation remain unclear. Here we reported that leptin significantly promoted the proliferation of hippocampal NSCs in a concentration-dependent pattern. Also, leptin efficiently reversed the inhibition of NSCs proliferation induced by corticosterone. Interestingly, pre-treatment with non-specific NMDA antagonist MK-801, specific NR2B antagonist Ro 25-6981, or small interfering RNA (siRNA) targeting NR2B, significantly blocked the effect of leptin on corticosterone-induced inhibition of NSCs proliferation. Furthermore, corticosterone significantly reduced the protein expression of NR2B, whereas pre-treatment with leptin greatly reversed the attenuation of NR2B expression caused by corticosterone in cultured hippocampal NSCs. Our findings demonstrate that leptin reverses the corticosterone-induced inhibition of NSCs proliferation. This process is, at least partially mediated by increased expression of NR2B subunits of NMDA receptors.

  5. Leptin reverses corticosterone-induced inhibition of neural stem cell proliferation through activating the NR2B subunits of NMDA receptors

    International Nuclear Information System (INIS)

    Highlights: • Leptin promotes the proliferation of neural stem cells isolated from embryonic mouse hippocampus. • Leptin reverses corticosterone-induced inhibition of neural stem cell proliferation. • The effects of leptin are partially mediated by upregulating NR2B subunits. - Abstract: Corticosterone inhibits the proliferation of hippocampal neural stem cells (NSCs). The removal of corticosterone-induced inhibition of NSCs proliferation has been reported to contribute to neural regeneration. Leptin has been shown to regulate brain development, improve angiogenesis, and promote neural regeneration; however, its effects on corticosterone-induced inhibition of NSCs proliferation remain unclear. Here we reported that leptin significantly promoted the proliferation of hippocampal NSCs in a concentration-dependent pattern. Also, leptin efficiently reversed the inhibition of NSCs proliferation induced by corticosterone. Interestingly, pre-treatment with non-specific NMDA antagonist MK-801, specific NR2B antagonist Ro 25-6981, or small interfering RNA (siRNA) targeting NR2B, significantly blocked the effect of leptin on corticosterone-induced inhibition of NSCs proliferation. Furthermore, corticosterone significantly reduced the protein expression of NR2B, whereas pre-treatment with leptin greatly reversed the attenuation of NR2B expression caused by corticosterone in cultured hippocampal NSCs. Our findings demonstrate that leptin reverses the corticosterone-induced inhibition of NSCs proliferation. This process is, at least partially mediated by increased expression of NR2B subunits of NMDA receptors

  6. Hydronephrotic urine in the obstructed kidney promotes urothelial carcinoma cell proliferation, migration, invasion through the activation of mTORC2-AKT and ERK signaling pathways.

    Directory of Open Access Journals (Sweden)

    Chi-Hao Chang

    Full Text Available Obstructive nephropathy is the most common presentation of urothelial carcinoma. The role of the urine in the obstructed kidney namely "hydronephrotic urine" in urothelial carcinoma has not been extensively explored. This study aims to evaluate whether hydronephrotic urine in the obstructed kidney could promote urothelial carcinoma. The hydronephrotic urine was collected from the obstructed kidneys of Sprague-Dawley rats induced by different periods of unilateral ureteral obstruction (UUO. By the inhibition of LY294002 and PD184352, we confirm that hydronephrotic urine promotes urothelial carcinoma cell (T24 and immortalized normal urothelial cells (E6 proliferation, migration and invasion in a dose-dependent manner through the activation of the mTORC2-AKT and ERK signaling pathways. Hydronephrotic urine also increases the expression of cyclin-D2, cyclin-B and CDK2. It also decreases the expression of p27 and p21 in both urothelial carcinoma cells and normal urothelial cells. By the protein array study, we demonstrate that many growth factors which promote tumor cell survival and metastasis are over-expressed in a time-dependent manner in the hydronephrotic urine, including beta-FGF, IFN-γ, PDGF-BB, PIGF, TGF-β, VEGF-A, VEGF-D and EGF. These results suggest that hydronephrotic urine promotes normal and malignant urothelial cells proliferation, migration and invasion, through the activation of the mTORC2-AKT and ERK signaling pathways. Further investigation using live animal models of tumor growth may be needed to clarify aspects of these statements.

  7. Granulosa cell proliferation differentiation and its role in follicular development

    Institute of Scientific and Technical Information of China (English)

    LU Cuiling; YANG Wei; HU Zhaoyuan; LIU Yixun

    2005-01-01

    Granuiosa cells (GCs) are the most important cells in the ovary that undergo serious changes morphologically and physiologically during the processes of follicular proliferation, differentiation, ovulation, lutenization and atresia. Oocyte (OC) directs GC proliferation and differentiation, while GCs influence OC maturation. Many ovarian factors are involved in the regulation of these processes via different molecular mechanisms and signal pathways. P38MAPK can selectively regulate steroidogenesis in GCs controlled by FSH; Transcript factors LRH-1 and DAX-1 play an important role in this process; FSH induces GC prolfferation and differentiation by stimulating PCNA and StAR expression and steroidogenesis. Activated ERK1/2 signal pathway may be involved in the FSH-regulated GC proliferation and differentiation. Therefore, GC is an ideal model for studying cell proliferation, differentiation and interaction,as well as signal transduction. This review briefly summarizes the latest data in the literature, including the results achieved in our laboratory.

  8. Human regulatory T cells suppress proliferation of B lymphoma cells.

    Science.gov (United States)

    Grygorowicz, Monika Anna; Biernacka, Marzena; Bujko, Mateusz; Nowak, Eliza; Rymkiewicz, Grzegorz; Paszkiewicz-Kozik, Ewa; Borycka, Ilona Sara; Bystydzienski, Zbigniew; Walewski, Jan; Markowicz, Sergiusz

    2016-08-01

    Activated regulatory T cells (Tregs) suppress proliferation and differentiation of normal B cells. In our study, allogeneic polyclonal CD4 (+) CD25 (+) Tregs and CD4 (+) CD25 (+) CD127(lo)Tregs expanded in vitro in the presence of rapamycin and low dose IL-2 suppressed proliferation of 11 out of 12 established lymphoma B-cell lines. The effect of expanded CD4 (+) CD25 (+) Tregs on survival of freshly isolated lymphoma B cells maintained in culture with soluble multimeric CD40L and IL-4 was variable across lymphoma entities. The survival of freshly isolated follicular lymphoma cells usually decreased in cocultures with CD4 (+) CD25 (+) Tregs. Treg effect on chronic lymphocytic leukemia/small lymphocytic lymphoma cells ranged from suppression to help in individual patients. CD4 (+) CD25 (+) Tregs or CD4 (+) CD25 (+) CD127(lo)Tregs expanded ex vivo with rapamycin could be used to suppress regrowth of residual lymphoma after autologous hematopoietic cell transplantation (HCT), and to counteract both graft-versus-host disease and lymphoma re-growth after allogeneic HCT in select patients with lymphoma susceptible to the regulation by Tregs. PMID:26758248

  9. p38MAPK activation is involved in androgen-independent proliferation of human prostate cancer cells by regulating IL-6 secretion

    International Nuclear Information System (INIS)

    Increased levels of serum interleukin-6 (IL-6) are frequently observed in patients with advanced, hormone-refractory prostate cancer. However, the precise mechanism of IL-6 regulation is still largely unknown. Since prostate cancer gradually progresses to an androgen-independent state despite the stress caused by various therapeutic agents, we hypothesized the stress-activated protein kinases (SAPKs) involvement in androgen-independent growth or IL-6 secretion of prostate cancer cells. Using PC-3 and DU145 human prostate cancer cells, we analyzed the role of SAPKs in IL-6 mediated cell growth and found that the p38MAPK and JNK are involved in androgen-independent cancer cell growth. Furthermore, IL-6 secretion by PC-3 and DU145 cells was significantly suppressed by SAPKs inhibitor, especially by p38MAPK inhibitor SB203580, but not by JNK inhibitor SP600125 nor by MEK inhibitor, PD98059. These results raised the possibility that the IL-6 mediated androgen-independent proliferation of PC-3 and DU145 cells is regulated at least partly via SAPKs signaling pathway especially through p38MAPK activation

  10. Proliferation of luteal steroidogenic cells in cattle.

    Directory of Open Access Journals (Sweden)

    Shin Yoshioka

    Full Text Available The rapid growth of the corpus luteum (CL after ovulation is believed to be mainly due to an increase in the size of luteal cells (hypertrophy rather than an increase in their number. However, the relationship between luteal growth and the proliferation of luteal steroidogenic cells (LSCs is not fully understood. One goal of the present study was to determine whether LSCs proliferate during CL growth. A second goal was to determine whether luteinizing hormone (LH, which is known have roles in the proliferation and differentiation of follicular cells, also affects the proliferation of LSCs. Ki-67 (a cell proliferation marker was expressed during the early, developing and mid luteal stages and some Ki-67-positive cells co-expressed HSD3B (a steroidogenic marker. DNA content in LSCs isolated from the developing CL increased much more rapidly (indicating rapid growth than did DNA content in LSCs isolated from the mid CL. The cell cycle-progressive genes CCND2 (cyclin D2 and CCNE1 (cyclin E1 mRNA were expressed more strongly in the small luteal cells than in the large luteal cells. LH decreased the rate of increase of DNA in LSCs isolated from the mid luteal stage but not in LSCs from the developing stage. LH suppressed CCND2 expression in LSCs from the mid luteal stage but not from the developing luteal stage. Furthermore, LH receptor (LHCGR mRNA expression was higher at the mid luteal stage than at the developing luteal stage. The overall results suggest that the growth of the bovine CL is due to not only hypertrophy of LSCs but also an increase in their number, and that the proliferative ability of luteal steroidogenic cells decreases between the developing and mid luteal stages.

  11. Satellite cell proliferation in adult skeletal muscle

    Science.gov (United States)

    Booth, Frank W. (Inventor); Thomason, Donald B. (Inventor); Morrison, Paul R. (Inventor); Stancel, George M. (Inventor)

    1995-01-01

    Novel methods of retroviral-mediated gene transfer for the in vivo corporation and stable expression of eukaryotic or prokaryotic foreign genes in tissues of living animals is described. More specifically, methods of incorporating foreign genes into mitotically active cells are disclosed. The constitutive and stable expression of E. coli .beta.-galactosidase gene under the promoter control of the Moloney murine leukemia virus long terminal repeat is employed as a particularly preferred embodiment, by way of example, establishes the model upon which the incorporation of a foreign gene into a mitotically-active living eukaryotic tissue is based. Use of the described methods in therapeutic treatments for genetic diseases, such as those muscular degenerative diseases, is also presented. In muscle tissue, the described processes result in genetically-altered satellite cells which proliferate daughter myoblasts which preferentially fuse to form a single undamaged muscle fiber replacing damaged muscle tissue in a treated animal. The retroviral vector, by way of example, includes a dystrophin gene construct for use in treating muscular dystrophy. The present invention also comprises an experimental model utilizable in the study of the physiological regulation of skeletal muscle gene expression in intact animals.

  12. Proliferating cell nuclear antigen in neutrophil fate.

    Science.gov (United States)

    Witko-Sarsat, Véronique; Ohayon, Delphine

    2016-09-01

    The life span of a neutrophil is a tightly regulated process as extended survival is beneficial for pathogen elimination and cell death necessary to prevent cytotoxic content release from activated neutrophils at the inflammatory site. Therefore, the control between survival and death must be a dynamic process. We have previously described that proliferating cell nuclear antigen (PCNA) which is known as a nuclear protein pivotal in DNA synthesis, is a key element in controlling neutrophil survival through its association with procaspases. Contrary to the dogma which asserted that PCNA has a strictly nuclear function, in mature neutrophils, PCNA is present exclusively within the cytosol due to its nuclear export at the end of the granulocytic differentiation. More recent studies are consistent with the notion that the cytosolic scaffold of PCNA is aimed at modulating neutrophil fate rather than simply preventing death. Ultimately, targeting neutrophil survival might have important applications not just in the field of immunology and inflammation, but also in hematology and transfusion. The neutrophil emerges as a unique and powerful cellular model to unravel the basic mechanisms governing the cell cycle-independent functions of PCNA and should be considered as a leader of the pack. PMID:27558345

  13. Integrin αv promotes proliferation by activating ERK 1/2 in the human lung cancer cell line A549.

    Science.gov (United States)

    Fu, Shijie; Fan, Limin; Pan, Xufeng; Sun, Yifeng; Zhao, Heng

    2015-02-01

    Lung cancer is a leading cause of cancer-related death worldwide, and non-small cell lung cancer (NSCLC) constitutes ~85% of lung cancers. However, the mechanisms underlying the progression of NSCLC remain unclear. In this study, we found the mRNA and protein expression levels of integrin αv are both increased in NSCLC tissues compared to healthy ones, which indicates that integrin αv may play an important role in NSCLC progression. To further investigate the roles of integrin αv in NSCLC, we overexpressed the integrin αv gene in the NSCLC cell line A549, and found that the cell proliferative ability increased. The apoptosis of A549 cells was inhibited with overexpression of integrin αv. To elucidate the molecular mechanism underlying the role of integrin αv in promoting NSCLC progression, we studied the expression of proteins from a number of important pathways associated with tumorigenesis, and found that the extracellular signal regulated protein kinase (ERK)1/2 signaling pathway may be involved in the mediation of the observed integrin αv effects. component of an important pathway for tumorigenesis, the ERK 1/2. Following inhibition of ERK 1/2 signaling, the proliferation of A549 cells induced by integrin αv was reduced, while the inhibition of apoptosis was attenuated. Our findings demonstrate that integrin αv promotes the proliferation of the human lung cancer cell line A549 by activating the ERK 1/2 signaling pathway, which suggests that this pathway may be a promising target for the treatment of human lung cancer.

  14. 5-Aza-2'-deoxycytidine Activates the p53/p21waf1/Cip1 Pathway to Inhibit Cell Proliferation

    Institute of Scientific and Technical Information of China (English)

    Wei-GuoZhu; TheresaHileman; YangKe; PeichangWang; ShaoliLu; WenruiDuan; ZunyanDai; TanjunTong; MiguelA.Villalona-Calero; ChristophPlass; GregoryA.Otterson

    2005-01-01

    In addition to its demethylating function, 5-aza-2'-de- oxycytidine (5-aza-CdR) also plays an important role in inducing cell cycle arrest, differentiation, and cell death. However, the mechanism by which 5-aza-CdR in. duces antineoplastic activity is not clear. In this study, we found that 5-aza-CdR at limited concentrations(0.01-5μM) induces inhibition of cell proliferation as well as increased p53/p21waf1/Cip1 expression in A549 cells (wild-type p53) but not in H1299 (p53-null) and H719 cells (p53 mutant). The p53-dependent p21wafa/Cip1 expression induced by 5-aza-CdR was not seen in A549 cells transfected with the wild-type human papilloma virus type-16 E6 gene that induces p53 degradation. Furthermore, deletion analysis and site-directed mutagenesis of the p21 promoter reveals that 5-aza-CdR induces p21wafa/Cip1 expression through two p53 binding sites in the p21 promoter. Finally, 5-aza-CdR-induced p21waf1/cip1 expression was dependent on DNA damage but not on DNA demethylation as demonstrated by comet assay and bisulfite sequencing, respectively. Our data provide useful clues for judging the therapeutic efficacy of 5-aza-CdR in the treatment of human cancer cells.

  15. Ligands for the peroxisome proliferator-activated receptor-γ have inhibitory effects on growth of human neuroblastoma cells in vitro

    International Nuclear Information System (INIS)

    The thiazolidinedione (TZD) or glitazone class of peroxisome proliferator-activated-γ (PPAR-γ) ligands not only induce adipocyte differentiation and increase insulin sensitivity, but also exert growth inhibitory effects on several carcinoma cell lines in vitro as well as in vivo. In the current study the in vitro effect of four PPAR-γ agonists (ciglitazone, pioglitazone, troglitazone, rosiglitazone) on the cell growth of seven human neuroblastoma cell lines (Kelly, LAN-1, LAN-5, LS, IMR-32, SK-N-SH, SH-SY5Y) was investigated. Growth rates were assessed by a colorimetric XTT-based assay kit. Expression of PPAR-γ protein was examined by immunohistochemistry and Western blot analysis. All glitazones inhibited in vitro growth and viability of the human neuroblastoma cell lines in a dose-dependent manner showing considerable effects only at high concentrations (10 μM and 100 μM). Effectiveness of the glitazones on neuroblastoma cell growth differed depending on the cell line and the agent. The presence of PPAR-γ protein was demonstrated in all cell lines. Our findings indicate that ligands for PPAR-γ may be useful therapeutic agents for the treatment of neuroblastoma. Thus the effect of glitazones on the growth of neuroblastoma should now be investigated in an in vivo animal model

  16. Quercus infectoria Gall Extract Enhanced the Proliferation and Activity of Human Fetal Osteoblast Cell Line (hFOB 1.19)

    OpenAIRE

    Hapidin, Hermizi; ROZELAN, Dalila; ABDULLAH, Hasmah; WAN HANAFFI, Wan Nurhidayah; Soelaiman, Ima Nirwana

    2015-01-01

    Background: The present study investigated the effects of Quercus infectoria (QI) gall extract on the proliferation, alkaline phosphatase (ALP), osteocalcin, and the morphology of a human fetal osteoblast cell line (hFOB 1.19).

  17. Cell cycle restriction by histone H2AX limits proliferation of adult neural stem cells

    OpenAIRE

    Fernando, R. N.; Eleuteri, B.; Abdelhady, S.; Nussenzweig, A; Andang, M; Ernfors, P.

    2011-01-01

    Adult neural stem cell proliferation is dynamic and has the potential for massive self-renewal yet undergoes limited cell division in vivo. Here, we report an epigenetic mechanism regulating proliferation and self-renewal. The recruitment of the PI3K-related kinase signaling pathway and histone H2AX phosphorylation following GABAA receptor activation limits subventricular zone proliferation. As a result, NSC self-renewal and niche size is dynamic and can be directly modulated in both directio...

  18. Nesfatin-1 inhibits ovarian epithelial carcinoma cell proliferation in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Yang; Pang, Xiaoyan; Dong, Mei; Wen, Fang, E-mail: wenfang64@hotmail.com; Zhang, Yi, E-mail: syzi960@yahoo.com

    2013-11-01

    Highlights: •Nesfatin-1 inhibits the proliferation and growth of HO-8910 cells by G1 phase arrest. •Nesfatin-1 enhances HO-8910 cell apoptosis. •Nesfatin-1 inhibits HO-8910 cell proliferation via mTOR and RhoA/ROCK signaling pathway. •The first report of nesfatin-1-mediated proliferation in ovarian epithelial carcinoma. -- Abstract: Nesfatin-1, an 82-amino-acid peptide derived from a 396-amino-acid precursor protein nucleobindin 2 (NUCB2), was originally identified in hypothalamic nuclei involved in the regulation of food intake. It was recently reported that nesfatin-1 is a novel depot specific adipokine preferentially produced by subcutaneous tissue, with obesity- and food deprivation-regulated expression. Although a relation between ovarian cancer mortality and obesity has been previously established, a role of nesfatin-1 in ovarian epithelial carcinoma remains unknown. The aim of the present study is to examine the effect of nesfatin-1 on ovary carcinoma cells proliferation. We found that nesfatin-1 inhibits the proliferation and growth of HO-8910 cells by G1 phase arrest, this inhibition could be abolished by nesfatin-1 neutralizing antibody. Nesfatin-1 enhances HO-8910 cell apoptosis, activation of mammalian target of rapamycin (mTOR) and RhoA/ROCK signaling pathway block the effects of nesfatin-1-induced apoptosis, therefore reverses the inhibition of HO-8910 cell proliferation by nesfatin-1. In conclusion, the present study demonstrated that nesfatin-1 can inhibit the proliferation in human ovarian epithelial carcinoma cell line HO-8910 cells through inducing apoptosis via mTOR and RhoA/ROCK signaling pathway. This study provides a novel regulatory signaling pathway of nesfatin-1-regulated ovarian epithelial carcinoma growth and may contribute to ovarian cancer prevention and therapy, especially in obese patients.

  19. Dietary bovine lactoferrin increases intestinal cell proliferation in neonatal piglets.

    Science.gov (United States)

    Reznikov, Elizabeth A; Comstock, Sarah S; Yi, Cuiyi; Contractor, Nikhat; Donovan, Sharon M

    2014-09-01

    Lactoferrin is a bioactive milk protein that stimulates cell proliferation in vitro; however, limited in vivo evidence exists to allow lactoferrin to be incorporated into infant formula. Herein, the effect of dietary bovine lactoferrin (bLF) on neonatal intestinal growth and maturation was investigated guided by the hypothesis that bLF would increase cellular proliferation leading to functional differences in neonatal piglets. Colostrum-deprived piglets were fed formula containing 0.4 [control (Ctrl)], 1.0 (LF1), or 3.6 (LF3) g bLF/L for the first 7 or 14 d of life. To provide passive immunity, sow serum was provided orally during the first 36 h of life. Intestinal cell proliferation, histomorphology, mucosal DNA concentration, enzyme activity, gene expression, and fecal bLF content were measured. Intestinal enzyme activity, DNA concentration, and villus length were unaffected by bLF. However, crypt proliferation was 60% greater in LF1- and LF3-fed piglets than in Ctrl piglets, and crypt depth and area were 20% greater in LF3-fed piglets than in Ctrl piglets. Crypt cells from LF3-fed piglets had 3-fold higher β-catenin mRNA expression than did crypt cells from Ctrl piglets. Last, feces of piglets fed bLF contained intact bLF, suggesting that some bLF was resistant to digestion and could potentially affect intestinal proliferation through direct interaction with intestinal epithelial cells. This study is the first to our knowledge to show that dietary bLF stimulates crypt cell proliferation in vivo. The increased β-catenin expression indicates that Wnt signaling may in part mediate the stimulatory effect of bLF on intestinal cell proliferation. PMID:25056692

  20. Expression of Peroxisome Proliferator-Activated Receptor γ (PPARγ) in Human Transitional Bladder Cancer and its Role in Inducing Cell Death1

    Science.gov (United States)

    Guan, You-Fei; Zhang, Ya-Hua; Breyer, Richard M; Davis, Linda; Breyer, Matthew D

    1999-01-01

    Abstract The present study examined the expression and role of the thiazolidinedione (TZD)-activated transcription factor, peroxisome proliferator-activated receptor γ (PPARγ), in human bladder cancers. In situ hybridization shows that PPARγ mRNA is highly expressed in all human transitional epithelial cell cancers (TCCa's) studied (n=11). PPARγ was also expressed in five TCCa cell lines as determined by RNase protection assays and immunoblot. Retinoid X receptor α (RXRα), a 9-cis-retinoic acid stimulated (9-cis-RA) heterodimeric partner of PPARγ, was also co-expressed in all TCCa tissues and cell lines. Treatment of the T24 bladder cancer cells with the TZD PPARγ agonist troglitazone, dramatically inhibited 3H-thymidine incorporation and induced cell death. Addition of the RXRα ligands, 9-cis-RA or LG100268, sensitized T24 bladder cancer cells to the lethal effect of troglitazone and two other PPARγ activators, ciglitazone and 15-deoxy-Δ2,14-PGJ2 (15dPGJ2). Troglitazone treatment increased expression of two cyclin-dependent kinase inhibitors, P21WAF1/CIP1 and p16INK4, and reduced cyclin D1 expression, consistent with G1 arrest. Troglitazone also induced an endogenous PPARγ target gene in T24 cells, adipocyte-type fatty acid binding protein (A-FABP), the expression of which correlates with bladder cancer differentiation. In situ hybridization shows that A-FABP expression is localized to normal uroepithelial cells as well as some TCCa's. Taken together, these results demonstrate that PPARγ is expressed in human TCCa where it may play a role in regulating TCCa differentiation and survival, thereby providing a potential target for therapy of uroepithelial cancers. PMID:10935488

  1. 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

  2. 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.

  3. Knockdown of peroxisome proliferator-activated receptor gamma coactivator-1 alpha increased apoptosis of human endometrial cancer HEC-1A cells

    Directory of Open Access Journals (Sweden)

    Yang H

    2016-08-01

    Full Text Available Hui Yang, Rui Yang, Hao Liu, Zhongqian Ren, Cuicui Wang, Da Li, Xiaoxin Ma Department of Obstetrics and Gynecology, Shengjing Hospital of China Medical University, Shenyang, Liaoning, People’s Republic of China Background: Peroxisome proliferator-activated receptor gamma coactivator-1 alpha (PGC-1α coactivates multiple transcription factors and regulates several metabolic processes. In this study, we focused on the roles of PGC-1α in the apoptosis of endometrial cancer HEC-1A cells. Materials and methods: PGC-1α expression in the HEC-1A cells was detected with real-time polymerase chain reaction and Western blot. Small interfering RNA directed against PGC-1α was designed and synthesized, and RNA interference technology was used to knock down PGC-1α mRNA and protein expression. Cell apoptosis, cell cycle, and mitochondrial membrane potential were then analyzed using flow cytometry. The expression of apoptotic proteins, Bcl-2 and Bax, was detected with Western blot. Results: The specific downregulation of PGC-1α expression in the HEC-1A cells increased their apoptosis through the mitochondrial apoptotic pathway by reducing the expression of Bcl-2 and increasing the expression of Bax. Conclusion: These results suggest that PGC-1α influences the apoptosis of HEC-1A cells and also provides a molecular basis for further investigation of the apoptotic mechanism in human endometrial cancer. Keywords: endometrial cancer, PGC-1α, apoptosis, Bcl-2, Bax

  4. Mouse strain-dependent changes in frequency and proliferation of hematopoietic stem cells during aging : Correlation between lifespan and cycling activity

    NARCIS (Netherlands)

    deHaan, G; Nijhof, W; VanZant, G

    1997-01-01

    We have quantified the frequency and proliferation of five subsets of primitive hematopoietic cells, using the cobblestone area forming cell (CAFC) assay, in marrow of five strains of mice with lifespans ranging from about 500 to 800 days. Stem cell characteristics were determined in young (6 weeks)

  5. Progesterone stimulates pancreatic cell proliferation in vivo

    NARCIS (Netherlands)

    Nieuwenhuizen, AG; Schuiling, GA; Liem, SMS; Moes, H; Koiter, TR; Uilenbroek, JTJ

    1999-01-01

    Treatment of cyclic and pregnant rats with progesterone stimulates cell proliferation within the islets of Langerhans. It was investigated whether this effect of progesterone depends on sex and/or the presence of the gonads or the presence of oestradiol, For this purpose, Silastic tubes containing p

  6. Conjugated linoleic acid isomers and their precursor fatty acids regulate peroxisome proliferator-activated receptor subtypes and major peroxisome proliferator responsive element-bearing target genes in HepG2 cell model

    Institute of Scientific and Technical Information of China (English)

    Sailas BENJAMIN; Silke FLOTHO; Torsten B(O)RCHERS; Friedrich SPENER

    2013-01-01

    The purpose of this study was to examine the induction profiles(as judged by quantitative reverse transcription polymerase chain reaction(qRT-PCR))of peroxisome proliferator-activated receptor(PPAR)α,β,Y subtypes and major PPAR-target genes bearing a functional peroxisome proliferator responsive element(PPRE)in HepG2 cell model upon feeding with cis-9,trans-11-octadecadienoic acid(9-CLA)or trans-10,cis-12-octadecadienoic acid (10-CLA)or their precursor fatty acids(FAs).HepG2 cells were treated with 100 μmol/L 9-CLA or 10-CLA or their precursor FAs,viz.,oleic,linoleic,and trans-11-vaccenic acids against bezafibrate control to evaluate the induction/expression profiles of PPAR α,β,Y subtypes and major PPAR-target genes bearing a functional PPRE,i.e.,fatty acid transporter(FAT),glucose transporter-2(GLUT-2),liver-type FA binding protein(L-FABP),acyl CoA oxidase-1 (ACOX-1),and peroxisomal bifunctional enzyme(PBE)with reference to β-actin as house keeping gene.Of the three housekeeping genes(glyceraldehyde 3-phosphate dehydrogenase(GAPDH),β-actin,and ubiquitin),β-actin was found to be stable.Dimethyl sulfoxide(DMSO),the common solubilizer of agonists,showed a significantly higher induction of genes analyzed.qRT-PCR profiles of CLAs and their precursor FAs clearly showed upregulation of FAT,GLUT-2,and L-FABP(~0.5-2.0-fold).Compared to 10-CLA,9-CLA decreased the induction of the FA metabolizing gene ACOX-1 less than did PBE,while 10-CLA decreased the induction of PBE less than did ACOX-1.Both CLAs and precursor FAs upregulated PPRE-bearing genes,but with comparatively less or marginal activation of PPAR subtypes.This indicates that the binding of CLAs and their precursor FAs to PPAR subtypes results in PPAR activation,thereby induction of the target transporter genes coupled with downstream lipid metabolising genes such as ACOX-1 and PBE.To sum up,the expression profiles of these candidate genes showed that CLAs and their precursor FAs are involved in lipid

  7. Traditional medicine yanggyuksanhwa-tang inhibits adipogenesis and suppresses proliferator-activated receptor gamma expression in 3T3-L1 cells

    Directory of Open Access Journals (Sweden)

    Soo-Jin Jeong

    2015-01-01

    Full Text Available Background: Yanggyuksanhwa-tang (YGSHT is a specific traditional Korean herbal formula for Soyangin according to Sasang constitutional philosophy. Although its biological activities against inflammation and cerebral infarction have been reporting, there is no information about the adipogenic activity of YGSHT. In the present study, we investigated the anti adipogenic activity of YGSHT to evaluate effects of YGSHT on adipogenesis in vitro. Materials and Methods: Using 3T3 L1 preadipocytes, we induced the cellular differentiation into adipocytes by adding insulin. Anti adipogenic activity of YGSHT was measured by oil red O staining, triglyceride assay, glycerol 3 phosphate dehydrogenase (GPDH activity test, and leptin assay. Results: YGSHT extract had no significant cytotoxicity in preadipocytes or differentiated adipocytes. YGSHT reduced the number of lipid droplets and content of triglyceride in adipose cells. YGSHT also significantly inhibited GPDH activity and decreased leptin production compared with control adipocytes. Down regulation of peroxisome proliferator activated receptor gamma (PPAR g expression at the messenger RNA level was observed in YGSHT treated adipocytes. Conclusion: Taken together, our data suggest that YGSHT has potential as an anti-obesity drug candidate.

  8. The inhibition of activated hepatic stellate cells proliferation by arctigenin through G0/G1 phase cell cycle arrest: persistent p27(Kip1) induction by interfering with PI3K/Akt/FOXO3a signaling pathway.

    Science.gov (United States)

    Li, Ao; Wang, Jun; Wu, Mingjun; Zhang, Xiaoxun; Zhang, Hongzhi

    2015-01-15

    Proliferation of hepatic stellate cells (HSCs) is vital for the development of fibrosis during liver injury. In this study, we describe that arctigenin (ATG), a major bioactive component of Fructus Arctii, exhibited selective cytotoxic activity via inhibiting platelet-derived growth factor-BB (PDGF-BB)-activated HSCs proliferation and arrested cell cycle at G0/G1 phase, which could not be observed in normal human hepatocytes in vitro. The cyclin-dependent kinase (CDK) 4/6 activities could be strongly inhibited by ATG through down-regulation of cyclin D1 and CDK4/6 expression in early G1 phase arrest. In the ATG-treated HSCs, the expression level of p27(Kip1) and the formation of CDK2-p27(Kip1) complex were also increased. p27(Kip1) silencing significantly attenuated the effect of ATG, including cell cycle arrest and suppression of proliferation in activated HSCs. We also found that ATG suppressed PDGF-BB-induced phosphorylation of Akt and its downstream transcription factor Forkhead box O 3a (FOXO3a), decreased binding of FOXO3a to 14-3-3 protein, and stimulated nuclear translocation of FOXO3a in activated HSCs. Furthermore, knockdown of FOXO3a expression by FOXO3a siRNA attenuated ATG-induced up-regulation of p27(Kip1) in activated HSCs. All the above findings suggested that ATG could increase the levels of p27(Kip1) protein through inhibition of Akt and improvement of FOXO3a activity, in turn inhibited the CDK2 kinase activity, and eventually caused an overall inhibition of HSCs proliferation. PMID:25498792

  9. The inhibition of activated hepatic stellate cells proliferation by arctigenin through G0/G1 phase cell cycle arrest: persistent p27(Kip1) induction by interfering with PI3K/Akt/FOXO3a signaling pathway.

    Science.gov (United States)

    Li, Ao; Wang, Jun; Wu, Mingjun; Zhang, Xiaoxun; Zhang, Hongzhi

    2015-01-15

    Proliferation of hepatic stellate cells (HSCs) is vital for the development of fibrosis during liver injury. In this study, we describe that arctigenin (ATG), a major bioactive component of Fructus Arctii, exhibited selective cytotoxic activity via inhibiting platelet-derived growth factor-BB (PDGF-BB)-activated HSCs proliferation and arrested cell cycle at G0/G1 phase, which could not be observed in normal human hepatocytes in vitro. The cyclin-dependent kinase (CDK) 4/6 activities could be strongly inhibited by ATG through down-regulation of cyclin D1 and CDK4/6 expression in early G1 phase arrest. In the ATG-treated HSCs, the expression level of p27(Kip1) and the formation of CDK2-p27(Kip1) complex were also increased. p27(Kip1) silencing significantly attenuated the effect of ATG, including cell cycle arrest and suppression of proliferation in activated HSCs. We also found that ATG suppressed PDGF-BB-induced phosphorylation of Akt and its downstream transcription factor Forkhead box O 3a (FOXO3a), decreased binding of FOXO3a to 14-3-3 protein, and stimulated nuclear translocation of FOXO3a in activated HSCs. Furthermore, knockdown of FOXO3a expression by FOXO3a siRNA attenuated ATG-induced up-regulation of p27(Kip1) in activated HSCs. All the above findings suggested that ATG could increase the levels of p27(Kip1) protein through inhibition of Akt and improvement of FOXO3a activity, in turn inhibited the CDK2 kinase activity, and eventually caused an overall inhibition of HSCs proliferation.

  10. Mitochondrial Regulation of Cell Cycle and Proliferation

    OpenAIRE

    Antico Arciuch, Valeria Gabriela; Elguero, María Eugenia; Poderoso, Juan José; Carreras, María Cecilia

    2012-01-01

    Eukaryotic mitochondria resulted from symbiotic incorporation of α-proteobacteria into ancient archaea species. During evolution, mitochondria lost most of the prokaryotic bacterial genes and only conserved a small fraction including those encoding 13 proteins of the respiratory chain. In this process, many functions were transferred to the host cells, but mitochondria gained a central role in the regulation of cell proliferation and apoptosis, and in the modulation of metabolism; accordingly...

  11. Exogenous hydrogen sulfide exerts proliferation/anti-apoptosis/angiogenesis/migration effects via amplifying the activation of NF-κB pathway in PLC/PRF/5 hepatoma cells.

    Science.gov (United States)

    Zhen, Yulan; Pan, Wanying; Hu, Fen; Wu, Hongfu; Feng, Jianqiang; Zhang, Ying; Chen, Jingfu

    2015-05-01

    Hydrogen sulfide (H2S) takes part in a diverse range of intracellular pathways and hss physical and pathological properties in vitro and in vivo. However, the effects of H2S on cancer are controversial and remain unclear. The present study investigates the effects of H2S on liver cancer progression via activating NF-κB pathway in PLC/PRF/5 hepatoma cells. PLC/PRF/5 hepatoma cells were pretreated with 500 µmol/l NaHS (a donor of H2S) for 24 h. The expression levels of CSE, CBS, phosphosphorylate (p)-NF-κB p65, caspase-3, COX-2, p-IκB and MMP-2 were measured by western blot assay. Cell viability was detected by cell counter kit 8 (CCK-8). Apoptotic cells were observed by Hoechst 33258 staining assay. The production level of H2S in cell culture medium was measured by using the sulfur-sensitive electrode method. The production of vascular endothelial growth factor (VEGF) was tested by enzyme-linked immunosorbent assay (ELISA). Our results showed that the production of H2S was dramatically increased in the PLC/PRF/5 hepatoma cells, compared with human LO2 hepatocyte cells group, along with the overexpression levels of CSE and CBS. Treatment of PLC/PRF/5 hepatoma cells with 500 µmol/l NaHS (a donor of H2S) for 24 h markedly increased the expression levels of CSE, CBS, p-IκB and NF-κB activation, leading to COX-2 and MMP-2 overexpression, and decreased caspase-3 production, as well as increased cell viability and decreased number of apoptotic cells. Otherwise, the production level of H2S and VEGF were also significantly increased. Furthermore, co-treatment of PLC/PRF/5 hepatoma cells with 500 µmol/l NaHS and 200 µmol/l PDTC for 24 h significantly overturned these indexes. The findings of the present study provide evidence that the NF-κB is involved in the NaHS-induced cell proliferation, anti-apoptisis, angiogenesis, and migration in PLC/PRF/5 hepatoma cells, and that the PDTC against the NaHS-induced effects were by inhibition of the NF-κB pathway.

  12. Peroxisome Proliferator-Activated Receptor Gamma Negatively Regulates the Differentiation of Bone Marrow-Derived Mesenchymal Stem Cells Toward Myofibroblasts in Liver Fibrogenesis

    Directory of Open Access Journals (Sweden)

    Shuangshuang Jia

    2015-11-01

    Full Text Available Background/Aims: Bone marrow-derived mesenchymal stem cells (BMSCs have been confirmed to have capacity to differentiate toward hepatic myofibroblasts, which contribute to fibrogenesis in chronic liver diseases. Peroxisome proliferator-activated receptor gamma (PPARγ, a ligand-activated transcription factor, has gained a great deal of recent attention as it is involved in fibrosis and cell differentiation. However, whether it regulates the differentiation of BMSCs toward myofibroblasts remains to be defined. Methods: Carbon tetrachloride or bile duct ligation was used to induce mouse liver fibrosis. Expressions of PPARγ, α-smooth muscle actin, collagen α1 (I and collagen α1 (III were detected by real-time RT-PCR and Western blot or immunofluorescence assay. Results: PPARγ expression was decreased in mouse fibrotic liver. In addition, PPARγ was declined during the differentiation of BMSCs toward myofibroblasts induced by transforming growth factor β1. Activation of PPARγ stimulated by natural or synthetic ligands suppressed the differentiation of BMSCs. Additionally, knock down of PPARγ by siRNA contributed to BMSC differentiation toward myofibroblasts. Furthermore, PPARγ activation by natural ligand significantly inhibited the differentiation of BMSCs toward myofibroblasts in liver fibrogenesis and alleviated liver fibrosis. Conclusions: PPARγ negatively regulates the differentiation of BMSCs toward myofibroblasts, which highlights a further mechanism implicated in the BMSC differentiation.

  13. Diazoxide promotes oligodendrocyte precursor cell proliferation and myelination.

    Directory of Open Access Journals (Sweden)

    Birgit Fogal

    Full Text Available BACKGROUND: Several clinical conditions are associated with white matter injury, including periventricular white matter injury (PWMI, which is a form of brain injury sustained by preterm infants. It has been suggested that white matter injury in this condition is due to altered oligodendrocyte (OL development or death, resulting in OL loss and hypomyelination. At present drugs are not available that stimulate OL proliferation and promote myelination. Evidence suggests that depolarizing stimuli reduces OL proliferation and differentiation, whereas agents that hyperpolarize OLs stimulate OL proliferation and differentiation. Considering that the drug diazoxide activates K(ATP channels to hyperpolarize cells, we tested if this compound could influence OL proliferation and myelination. METHODOLOGY/FINDINGS: Studies were performed using rat oligodendrocyte precursor cell (OPC cultures, cerebellar slice cultures, and an in vivo model of PWMI in which newborn mice were exposed to chronic sublethal hypoxia (10% O(2. We found that K(ATP channel components Kir 6.1 and 6.2 and SUR2 were expressed in oligodendrocytes. Additionally, diazoxide potently stimulated OPC proliferation, as did other K(ATP activators. Diazoxide also stimulated myelination in cerebellar slice cultures. We also found that diazoxide prevented hypomyelination and ventriculomegaly following chronic sublethal hypoxia. CONCLUSIONS: These results identify KATP channel components in OLs and show that diazoxide can stimulate OL proliferation in vitro. Importantly we find that diazoxide can promote myelination in vivo and prevent hypoxia-induced PWMI.

  14. The influence of galvanic currents and voltage on the proliferation activity of lymphocytes and expression of cell surface molecules.

    Science.gov (United States)

    Podzimek, S; Hána, K; Miksovský, M; Pousek, L; Matucha, P; Meloun, M; Procházková, J

    2008-01-01

    Release of metal ions from dental metal fillings supported by galvanism can cause local or general pathological problems in sensitive and genetically susceptible individuals. We aimed to investigate in vitro lymphocyte responses and expression of surface molecules influenced by galvanic currents and voltage. Human peripheral blood lymphocytes were influenced by galvanic currents and voltages and lymphocyte proliferation was measured. Control samples were not exposed to the influence of galvanism. We also studied the expression of surface molecules by the FACS analysis. A 15-h and shorter influence of almost all tested currents and voltages caused a significant decrease in lymphocyte proliferation and the 15-h influence of 20 microA currents significantly increased expression of surface molecules CD 19, 11a/18, 19/69 and 19/95. An influence of 10 and 3 microA currents led to a significant decrease in the expression of surface molecules CD 3, 11a/18, 3/69 and 3/95 and to a significant increase in CD 19 expression. An 80 mV voltage influence led to a significant decrease in the expression of surface molecules CD 3, 11a/18, 3/69, 3/95, 19/69 and 19/95, and 200 and 300 mV voltages significantly decreased the expression of surface molecules CD 3, 19, 11a/18, 3/95 and 19/95 and significantly increased CD 19/69 expression. A long-lasting influence of galvanism can, in sensitive and genetically susceptible individuals, influence lymphocyte proliferation and surface molecule expression. The threshold for pathological values of 5 microA for galvanic currents and 100 mV for galvanic voltage was confirmed.

  15. Expression of constitutively active 4EBP-1 enhances p27Kip1 expression and inhibits proliferation of MCF7 breast cancer cells

    Directory of Open Access Journals (Sweden)

    Miskimins W Keith

    2003-02-01

    Full Text Available Abstract Background Eukaryotic initiation factor 4E (eIF4E is essential for cap-dependent initiation of translation. Cell proliferation is associated with increased activity of eIF4E and elevated expression of eIF4E leads to tumorigenic transformation. Many tumors express very high levels of eIF4E and this may be a critical factor in progression of the disease. In contrast, overexpression of 4EBP, an inhibitor of eIF4E, leads to cell cycle arrest and phenotypic reversion of some transformed cells. Results A constitutively active form of 4EBP-1 was inducibly expressed in the human breast cancer cell line MCF7. Induction of constitutively active 4EBP-1 led to cell cycle arrest. This was not associated with a general inhibition of protein synthesis but rather with changes in specific cell cycle regulatory proteins. Cyclin D1 was downregulated while levels of the CDK inhibitor p27Kip1 were increased. The levels of cyclin E and CDK2 were unaffected but the activity of CDK2 was significantly reduced due to increased association with p27Kip1. The increase in p27Kip1 did not reflect changes in p27Kip1 mRNA or degradation rates. Rather, it was associated with enhanced synthesis of the protein, even though 4EBP-1 is expected to inhibit translation. This could be explained, at least in part, by the ability of the p27Kip1 5'-UTR to mediate cap-independent translation, which was also enhanced by expression of constitutively active 4EBP-1. Conclusions Expression of active 4EBP-1 in MCF7 leads to cell cycle arrest which is associated with downregulation of cyclin D1 and upregulation of p27Kip1. Upregulation of p27Kip1reflects increased synthesis which corresponds to enhanced cap-independent translation through the 5'-UTR of the p27Kip1 mRNA.

  16. Ginsenosides stimulated the proliferation of mouse spermatogonia involving activation of protein kinase C

    Institute of Scientific and Technical Information of China (English)

    Da-lei ZHANG; Kai-ming WANG; Cai-qiao ZHANG

    2009-01-01

    The effect of ginsenosides on proliferation of type A spermatogonia was investigated in 7-day-old mice.Spermatogonia were characterized by c-kit expression and cell proliferation was assessed by immunocytochemical demonstration of proliferating cell nuclear antigen (PCNA).After 72-h culture,Sertoli cells formed a confluent monolayer to which numerous spermatogonial colonies attached.Spermatogonia were positive for c-kit staining and showed high proliferating activity by PCNA expression.Ginsenosides (1.0~10 μg/ml) significantly stimulated proliferation of spermatogonia.Activation of protein kinase C (PKC) elicited proliferation of spermatogonia at 10-8 to 107 mol/L and the PKC inhibitor H7 inhibited this effect.Likewise,ginsenosides-stimulated spermatogonial proliferation was suppressed by combined treatment of H7.These results indicate that the proliferating effect ofginsenosides on mouse type A spermatogonia might be mediated by a mechanism involving the PKC signal transduction pathway.

  17. NKX3.1 activates expression of insulin-like growth factor binding protein-3 to mediate insulin-like growth factor-I signaling and cell proliferation.

    Science.gov (United States)

    Muhlbradt, Erin; Asatiani, Ekaterina; Ortner, Elizabeth; Wang, Antai; Gelmann, Edward P

    2009-03-15

    NKX3.1 is a homeobox gene that codes for a haploinsufficient prostate cancer tumor suppressor. NKX3.1 protein levels are down-regulated in the majority of primary prostate cancer tissues. NKX3.1 expression in PC-3 cells increased insulin-like growth factor binding protein-3 (IGFBP-3) mRNA expression 10-fold as determined by expression microarray analysis. In both stably and transiently transfected PC-3 cells and in LNCaP cells, NKX3.1 expression increased IGFBP-3 mRNA and protein expression. In prostates of Nkx3.1 gene-targeted mice Igfbp-3 mRNA levels correlated with Nkx3.1 copy number. NKX3.1 expression in PC-3 cells attenuated the ability of insulin-like growth factor-I (IGF-I) to induce phosphorylation of type I IGF receptor (IGF-IR), insulin receptor substrate 1, phosphatidylinositol 3-kinase, and AKT. The effect of NKX3.1 on IGF-I signaling was not seen when cells were exposed to long-R3-IGF-I, an IGF-I variant peptide that does not bind to IGFBP-3. Additionally, small interfering RNA-induced knockdown of IGFBP-3 expression partially reversed the attenuation of IGF-IR signaling by NKX3.1 and abrogated NKX3.1 suppression of PC-3 cell proliferation. Thus, there is a close relationship in vitro and in vivo between NKX3.1 and IGFBP-3. The growth-suppressive effects of NKX3.1 in prostate cells are mediated, in part, by activation of IGFBP-3 expression. PMID:19258508

  18. Ras-activated RSK1 phosphorylates EBP50 to regulate its nuclear localization and promote cell proliferation.

    Science.gov (United States)

    Lim, Hooi Cheng; Jou, Tzuu-Shuh

    2016-03-01

    Differential subcellular localization of EBP50 leads to its controversial role in cancer biology either as a tumor suppressor when it resides at the membrane periphery, or a tumor facilitator at the nucleus. However, the mechanism behind nuclear localization of EBP50 remains unclear. A RNA interference screening identified the downstream effector of the Ras-ERK cascade, RSK1, as the molecule unique for nuclear transport of EBP50. RSK1 binds to EBP50 and phosphorylates it at a conserved threonine residue at position 156 (T156) under the regulation of growth factor. Mutagenesis experiments confirmed the significance of T156 residue in nuclear localization of EBP50, cellular proliferation, and oncogenic transformation. Our study sheds light on a possible therapeutic strategy targeting at this aberrant nuclear expression of EBP50 without affecting the normal physiological function of EBP50 at other subcellular localization.

  19. Soluble interleukin-2 receptors inhibit interleukin 2-dependent proliferation and cytotoxicity: explanation for diminished natural killer cell activity in cutaneous T-cell lymphomas in vivo?

    OpenAIRE

    Dummer, R.; Posseckert, G.; F. NESTLE; Witzgall, R.; Burger, M.; Becker, J C; Schäfer, E; Wiede, J.; Sebald, Walter; Burg, G

    2012-01-01

    In patients with cutaneous T-cell lymphomas (CTCL), soluble interleukin-2 receptor serum levels (sIL-2R) were determined by ELISA technique, and natural killer cell (NK) activity, by a 4-h chromium-51 release assay. Decrease of NK activity correlated with the augmentation of serum sIL-2R. After a 4-d stimulation with interleukin 2 CTCL patients' peripheral mononuclear cells (PMC) showed an increase of cytotoxic activity similar to that in healthy donors' PMC. Normal donors' PMC demonstrated a...

  20. Tumor necrosis factor alpha promotes the proliferation of human nucleus pulposus cells via nuclear factor-κB, c-Jun N-terminal kinase, and p38 mitogen-activated protein kinase.

    Science.gov (United States)

    Wang, Xiao-Hu; Hong, Xin; Zhu, Lei; Wang, Yun-Tao; Bao, Jun-Ping; Liu, Lei; Wang, Feng; Wu, Xiao-Tao

    2015-04-01

    Although tumor necrosis factor alpha (TNF-α) is known to play a critical role in intervertebral disc (IVD) degeneration, the effect of TNF-α on nucleus pulposus (NP) cells has not yet been elucidated. The aim of this study was to explore the effect of TNF-α on proliferation of human NP cells. NP cells were treated with different concentrations of TNF-α. Cell proliferation was determined by cell counting kit-8 (CCK-8) analysis and Ki67 immunofluorescence staining, and expression of cyclin B1 was studied by quantitative real-time RT-PCR. Cell cycle was measured by flow cytometry and cell apoptosis was analyzed using an Annexin V-fluorescein isothiocyanate (FITC) & propidium iodide (PI) apoptosis detection kit. To identify the mechanism by which TNF-α induced proliferation of NP cells, selective inhibitors of major signaling pathways were used and Western blotting was carried out. Treatment with TNF-α increased cell viability (as determined by CCK-8 analysis) and expression of cyclin B1 and the number of Ki67-positive and S-phase NP cells, indicating enhancement of proliferation. Consistent with this, NP cell apoptosis was suppressed by TNF-α treatment. Moreover, inhibition of NF-κB, c-Jun N-terminal kinase (JNK), and p38 mitogen-activated protein kinase (MAPK) blocked TNF-α-stimulated proliferation of NP cells. In conclusion, the current findings suggest that the effect of TNF-α on IVD degeneration involves promotion of the proliferation of human NP cells via the NF-κB, JNK, and p38 MAPK pathways.

  1. Stimulation of murine stem cell proliferation by circulating activities produced during the recovery of a radiation-induced hematopoietic injury. Estimulacion proliferativa de celulas madre hematopoyeticas de raton por actividades circulantes producidas durante la recuperacion de un dano hematopoyetico radioinducido

    Energy Technology Data Exchange (ETDEWEB)

    Grande Azanedo, M.T.

    1989-02-01

    The proliferative activity of CFU-S, low in normal steady state, increases after treatment with different aggressors, i.e., radiation. This stimulation has been attributed in part to a local regulation system of stem cell proliferation, and at least in part to a humoral regulatory system. In the present work it has been investigated the role that circulating activities have in the CFU-S stimulation, by means of in vitro and in vivo incubation assays with diffusion chambers. The results show that bone marrow of mice irradiated with 5 Gy produces in vitro diffusible activities capable of stimulating the CFU-S proliferation. As well with this same dose circulating activities are also produced in vivo. In addition we have observed that these activities are only released during the periods of active hematopoietic regeneration that follow irradiation with moderate doses (1.5 and 5 Gy). In another set of experiments we saw that the stimulating activities are also detected in serum of mice irradiated with 5 Gy. These serum activities modify the proliferative state of very primitive precursors (12 d CFU-S). When the serum activities are added to long term bone marrow cultures the CFU-S are also stimulated to proliferate. Finally, we observed that the radiation-induced serum activities stimulate the proliferation of bone marrow CFU-S when injected into normal mice, suggesting that such activities are involved in the regulation of CFU-S proliferation.

  2. Upregulation of peroxisome proliferator-activated receptors and liver fatty acid binding protein in hepatic cells of broiler chicken supplemented with conjugated linoleic acids

    OpenAIRE

    Suriya Kumari Ramiah; Goh Y. Meng; Mahdi Ebrahimi

    2015-01-01

    Since conjugated linoleic acid (CLA) has structural and physiological characteristics similar to peroxisome proliferators, it is hypothesized that CLA would upregulate peroxisome proliferator-activated receptor (PPAR) and liver fatty acid binding protein (LFABP) in the liver of broiler chicken. The aim of the present study was to determine fatty acid composition of liver in CLA-fed broiler chickens and the genes associated with hepatic lipid metabolism. A total of 180-day-old broiler chicks w...

  3. Cell proliferation inhibition in reduced gravity

    Science.gov (United States)

    Moos, P. J.; Fattaey, H. K.; Johnson, T. C.; Spooner, B. S. (Principal Investigator)

    1994-01-01

    Extended durations of spaceflight have been shown to be deleterious on an organismic level; however, mechanisms underlying cellular sensitivity to the gravitational environment remain to be elucidated. The majority of the gravitational studies to date indicates that cell regulatory pathways may be influenced by their gravitational environment. Still, few cell biology experiments have been performed in space flight and even fewer experiments have been repeated on subsequent flights. With flight opportunities on STS-50, 54, and 57, Sf9 cells were flown in the BioServe Fluids Processing Apparatus and cell proliferation was measured with and without exposure to a cell regulatory sialoglycopeptide (CeReS) inhibitor. Results from these flights indicate that the Sf9 cells grew comparable to ground controls, that the CeReS inhibitor bound to its specific receptor, and that its signal transduction cascade was not gravity sensitive.

  4. Anti-tumor effects of Rubratoxin B on cell toxicity, inhibition of cell proliferation, cytotoxic activity and matrix metalloproteinase-2,9.

    Science.gov (United States)

    Wang, Tao; Zhang, Yi; Wang, Yi; Pei, Yue-hu

    2007-06-01

    Terrestrial fungi are a prolific source of metabolites with significant biological activities. Many important anticancer, antifungal and antibacterial chemotherapeutics are either microbial metabolites or semisynthetic derivatives. Investigating the metabolites of fungi may increase the chance of finding novel compounds. A bioassay-guided fractionation of soil fungus Penicillium purpurogenum fermentation, yielded the metabolite Rubratoxin B using morphological deformation of Pyricularia oryzae mycelia. Analysis by flow cytometry showed that Rubratoxin B inhibited the cell cycle progression of tsFT210 cells in the G2/M phase at the concentration of 24 microM. Cytotoxic activity analysis showed that Rubratoxin B has a cytotoxic activity and IC50 was 67.3 +/- 1.4 microM on human fibrosarcoma cell (HT1080), and Rubratoxin B exhibited inhibitory activities against matrix metalloproteinase (MMP)-2 and 9 on HT 1080 cells with an inhibitory rate of 61.5% and 74.7% at 30 microM, respectively. PMID:17306501

  5. Isorhamnetin inhibits cell proliferation and induces apoptosis in breast cancer via Akt and mitogen‑activated protein kinase kinase signaling pathways.

    Science.gov (United States)

    Hu, Shan; Huang, Liming; Meng, Liwei; Sun, He; Zhang, Wei; Xu, Yingchun

    2015-11-01

    Breast cancer is the most common cause of female cancer-associated mortality. Although treatment options, including chemotherapy, radiotherapy and surgery have led to a decline in the mortality rates associated with breast cancer, drug resistance remains one of the predominant causes for poor prognosis and high recurrence rates. The present study investigated the potential effects of the natural product, isorhamnetin on breast cancer, and examined the effects of isorhamnetin on the Akt/mammalian target of rapamycin (mTOR) and the mitogen-activated protein kinase (MAPK)/MAPK kinase (MEK) signaling cascades, which are two important signaling pathways for endocrine therapy resistance in breast cancer. The results of the present study indicate that isorhamnetin inhibits cell proliferation and induces cell apoptosis. In addition, isorhamnetin was observed to inhibit the Akt/mTOR and the MEK/extracellular signal-regulated kinase phosphorylation cascades. The inhibition of these two signaling pathways was attenuated by the two Akt and MEK1 inhibitors, but not by the nuclear factor-κB inhibitor. Furthermore, epidermal growth factor inhibited the effects of isorhamnetin via activation of the Akt and MEK signaling pathways. These results indicate that isorhamnetin exhibits antitumor effects in breast cancer, which are mediated by the Akt and MEK signaling pathways. PMID:26502751

  6. Signal peptide peptidase-mediated nuclear localization of heme oxygenase-1 promotes cancer cell proliferation and invasion independent of its enzymatic activity.

    Science.gov (United States)

    Hsu, F-F; Yeh, C-T; Sun, Y-J; Chiang, M-T; Lan, W-M; Li, F-A; Lee, W-H; Chau, L-Y

    2015-04-30

    Heme oxygenase-1 (HO-1) is a heme-degrading enzyme anchored in the endoplasmic reticulum by a carboxyl-terminal transmembrane segment (TMS). HO-1 is highly expressed in various cancers and its nuclear localization is associated with the progression of some cancers. Nevertheless, the mechanism underlying HO-1 nuclear translocation and its pathological significance remain elusive. Here we show that the signal peptide peptidase (SPP) catalyzes the intramembrane cleavage of HO-1. Coexpression of HO-1 with wild-type SPP, but not a dominant-negative SPP, promoted the nuclear localization of HO-1 in cells. Mass spectrometry analysis of cytosolic HO-1 isolated from HeLa cells overexpressing HO-1 and SPP revealed two adjacent intramembrane cleavage sites located after S275 and F276 within the TMS. Mutations of S275F276 to A275L276 significantly hindered SPP-mediated HO-1 cleavage and nuclear localization. Nuclear HO-1 was detected in A549 and DU145 cancer cell lines expressing high levels of endogenous HO-1 and SPP. SPP knockdown or inhibition significantly reduced nuclear HO-1 localization in A549 and DU145 cells. The positive nuclear HO-1 stain was also evident in lung cancer tissues expressing high levels of HO-1 and SPP. Overexpression of a truncated HO-1 (t-HO-1) lacking the TMS in HeLa and H1299 cells promoted cell proliferation and migration/invasion. The effect of t-HO-1 was not affected by a mutation in the catalytic site. However, blockade of t-HO-1 nuclear localization abolished t-HO-1-mediated effect. The tumorigenic effect of t-HO-1 was also demonstrated in the mouse model. These findings disclose that SPP-mediated intramembrane cleavage of HO-1 promotes HO-1 nuclear localization and cancer progression independent of HO-1 enzymatic activity.

  7. Retinoic Acid-mediated Nuclear Receptor Activation and Hepatocyte Proliferation

    Science.gov (United States)

    Bushue, Nathan; Wan, Yu-Jui Yvonne

    2016-01-01

    Due to their well-known differentiation and apoptosis-inducing abilities, retinoic acid (RA) and its analogs have strong anti-cancer efficacy in human cancers. However, in vivo RA is a liver mitogen. While speculation has persisted that RA-mediated signaling is likely involved in hepatocyte proliferation during liver regeneration, direct evidence is still required. Findings in support of this proposition include observations that a release of retinyl palmitate (the precursor of RA) occurs in liver stellate cells following liver injury. Nevertheless, the biological action of this released vitamin A is virtually unknown. More likely is that the released vitamin A is converted to RA, the biological form, and then bound to a specific receptor (retinoid x receptor; RXRα), which is most abundantly expressed in the liver. Considering the mitogenic effects of RA, the RA-activated RXRα would likely then influence hepatocyte proliferation and liver tissue repair. At present, the mechanism by which RA stimulates hepatocyte proliferation is largely unknown. This review summarizes the activation of nuclear receptors (peroxisome proliferator activated receptor-α, pregnane x receptor, constitutive androstane receptor, and farnesoid x receptor) in an RXRα dependent manner to induce hepatocyte proliferation, providing a link between RA and its proliferative role.

  8. Tetraspanin CD9 modulates human lymphoma cellular proliferation via histone deacetylase activity

    Energy Technology Data Exchange (ETDEWEB)

    Herr, Michael J. [Vascular Biology Center of Excellence, The University of Tennessee Health Science Center, Memphis, TN 38163 (United States); Department of Medicine, The University of Tennessee Health Science Center, Memphis, TN 38163 (United States); Department of Molecular Sciences, The University of Tennessee Health Science Center, Memphis, TN 38163 (United States); Department of Surgery, The University of Tennessee Health Science Center, Memphis, TN 38163 (United States); Longhurst, Celia M.; Baker, Benjamin [Vascular Biology Center of Excellence, The University of Tennessee Health Science Center, Memphis, TN 38163 (United States); Homayouni, Ramin [Department of Biology, Bioinformatics Program, University of Memphis, Memphis, TN 38152 (United States); Speich, Henry E.; Kotha, Jayaprakash [Vascular Biology Center of Excellence, The University of Tennessee Health Science Center, Memphis, TN 38163 (United States); Jennings, Lisa K., E-mail: ljennings@uthsc.edu [Vascular Biology Center of Excellence, The University of Tennessee Health Science Center, Memphis, TN 38163 (United States); Department of Medicine, The University of Tennessee Health Science Center, Memphis, TN 38163 (United States); Department of Molecular Sciences, The University of Tennessee Health Science Center, Memphis, TN 38163 (United States); Department of Surgery, The University of Tennessee Health Science Center, Memphis, TN 38163 (United States); Department of Biology, Bioinformatics Program, University of Memphis, Memphis, TN 38152 (United States)

    2014-05-16

    Highlights: • CD9 is differentially expressed in human Burkitt’s lymphoma cells. • We found that CD9 expression promotes these cells proliferation. • CD9 expression also increases HDAC activity. • HDAC inhibition decreased both cell proliferation and importantly CD9 expression. • CD9 may dictate HDAC efficacy and play a role in HDAC regulation. - Abstract: Non-Hodgkin Lymphoma (NHL) is a type of hematological malignancy that affects two percent of the overall population in the United States. Tetraspanin CD9 is a cell surface protein that has been thoroughly demonstrated to be a molecular facilitator of cellular phenotype. CD9 expression varies in two human lymphoma cell lines, Raji and BJAB. In this report, we investigated the functional relationship between CD9 and cell proliferation regulated by histone deacetylase (HDAC) activity in these two cell lines. Introduction of CD9 expression in Raji cells resulted in significantly increased cell proliferation and HDAC activity compared to Mock transfected Raji cells. The increase in CD9–Raji cell proliferation was significantly inhibited by HDAC inhibitor (HDACi) treatment. Pretreatment of BJAB cells with HDAC inhibitors resulted in a significant decrease in endogenous CD9 mRNA and cell surface expression. BJAB cells also displayed decreased cell proliferation after HDACi treatment. These results suggest a significant relationship between CD9 expression and cell proliferation in human lymphoma cells that may be modulated by HDAC activity.

  9. Microglial recruitment, activation, and proliferation in response to primary demyelination

    DEFF Research Database (Denmark)

    Remington, Leah T; Babcock, Alicia A; Zehntner, Simone P;

    2007-01-01

    microglial numbers. Microglia adopted an activated phenotype during demyelination, up-regulating major histocompatibility class I and B7.2/CD86. A subpopulation of CD45(dim-high) microglia that expressed reduced levels of CD11b emerged during demyelination. These microglia expressed CD11c and were potent...... antigen-presenting cells in vitro. T cells were recruited to the demyelinated corpus callosum but did not appear to be activated. Our study highlights the role of microglia as a heterogeneous population of cells in primary demyelination, with the capacity to present antigen, proliferate, and migrate...

  10. NKX3.1 Activates Expression of IGFBP-3 to Mediate IGF-I Signaling and Cell Proliferation

    OpenAIRE

    Muhlbradt, Erin; Asatiani, Ekaterina; Ortner, Elizabeth; Wang, Antai; Gelmann, Edward P.

    2009-01-01

    NKX3.1 is a homeobox gene that codes for a haploinsufficient prostate cancer tumor suppressor. NKX3.1 protein levels are down regulated in the majority of primary prostate cancer tissues. NKX3.1 expression in PC-3 cells increased IGFBP-3 mRNA expression 10-fold as determined by expression microarray analysis. In both stably and transiently transfected PC-3 cells and in LNCaP cells NKX3.1 expression increased IGFBP-3 mRNA and protein expression. In prostates of Nkx3.1 gene-targeted mice Igfbp-...

  11. Selective stimulation of prostatic carcinoma cell proliferation by transferrin.

    OpenAIRE

    M.C. Rossi; Zetter, B R

    1992-01-01

    Aggressive prostatic carcinomas most frequently metastasize to the skeletal system. We have previously shown that cultured human prostatic carcinoma cells are highly responsive to growth factors found in human bone marrow. To identify the factor(s) responsible for the increased prostatic carcinoma cell proliferation, we fractionated crude bone marrow preparations by using hydroxylapatite HPLC. The major activity peak contained two high molecular weight bands (M(r) = 80,000 and 69,000) that cr...

  12. MicroRNA-500 sustains nuclear factor-κB activation and induces gastric cancer cell proliferation and resistance to apoptosis

    Science.gov (United States)

    Yuan, Zhongyu; Liu, Junling; Sun, Jian; Lei, Fangyong; Wu, Shu; Li, Su; Zhang, Dongsheng

    2015-01-01

    Ubiquitin deconjugation of key signalling molecules by deubiquitinases (DUBs) such as cylindromatosis (CYLD), A20, and OTU deubiquitinase 7B (OTUD7B) has emerged as an important regulatory mechanism in the downregulation of NF-κB signalling and homeostasis. However, how these serial negative regulations are simultaneously disrupted to result in constitutive activation of NF-κB signalling in cancers remains puzzling. Here, we report that the miR-500 directly repressed the expression of CYLD, OTUD7B, and the A20 complex component Tax1-binding protein 1 (TAX1BP1), leading to ubiquitin conjugation of receptor-interacting protein 1 (RIP1) and sustained NF-ĸB activation. Furthermore, we found that miR-500 promoted gastric cancer cell proliferation, survival, and tumorigenicity. Importantly, miR-500 was upregulated in gastric cancer and was highly correlated with malignant progression and poor survival. Hence, we report the uncovering of a novel mechanism for constitutive NF-κB activation, indicating the potentially pivotal role of miR-500 in the progression of gastric cancer. PMID:25595906

  13. Novel factors modulating human β-cell proliferation.

    Science.gov (United States)

    Shirakawa, J; Kulkarni, R N

    2016-09-01

    β-Cell dysfunction in type 1 and type 2 diabetes is accompanied by a progressive loss of β-cells, and an understanding of the cellular mechanism(s) that regulate β-cell mass will enable approaches to enhance hormone secretion. It is becoming increasingly recognized that enhancement of human β-cell proliferation is one potential approach to restore β-cell mass to prevent and/or cure type 1 and type 2 diabetes. While several reports describe the factor(s) that enhance β-cell replication in animal models or cell lines, promoting effective human β-cell proliferation continues to be a challenge in the field. In this review, we discuss recent studies reporting successful human β-cell proliferation including WS6, an IkB kinase and EBP1 inhibitor; harmine and 5-IT, both DYRK1A inhibitors; GNF7156 and GNF4877, GSK-3β and DYRK1A inhibitors; osteoprotegrin and Denosmab, receptor activator of NF-kB (RANK) inhibitors; and SerpinB1, a protease inhibitor. These studies provide important examples of proteins and pathways that may prove useful for designing therapeutic strategies to counter the different forms of human diabetes. PMID:27615134

  14. Collagen coated tantalum substrate for cell proliferation.

    Science.gov (United States)

    Li, Yinli; Zhang, Shuai; Guo, Lijun; Dong, Mingdong; Liu, Bo; Mamdouh, Wael

    2012-06-15

    The extracellular matrix (ECM) plays a key role in cell culture in various physiological and pathological processes in the field of tissue engineering. Recently, the type I collagen ECM has been widely utilized in vitro model systems for the attachment of many different cell lines since it has multi-functions in human tissues. For example it accounts for 6% of the weight of strong, tendinous muscles. In this paper, we reported a new material by coating tantalum (Ta), one highly biocompatible metal, with type I collagen fibrils. The morphology of the new material was studied by high resolution atomic force microscope. It was shown that the adhesion force between type I collagen fibrils network and Ta was strong enough to overcome surface defects. A possible way to explain the phenomenon is that the longitudinal periodicity of collagen fibrils matches the grain size of the Ta domains, which results in increase of the physical adsorption contact area, thereby inducing the dramatic adhesion enhancement between collagen fibrils and Ta. The obtained material was then employed as a template for cell proliferation. Although the surface of this template is more hydrophobic by comparison with the bare Ta surface, the cells on this material were successfully incubated, indicating that the collagen coated Ta might be used as the buffer layer for proliferating cells in hydrophobic biomaterials. PMID:22494669

  15. Fibrosarcoma versus fibromatoses and cellular nodular fasciitis. A comparative study of their proliferative activity using proliferating cell nuclear antigen, DNA flow cytometry, and p53.

    Science.gov (United States)

    Oshiro, Y; Fukuda, T; Tsuneyoshi, M

    1994-07-01

    We analyzed the proliferative activities, immunoreactivity of the p53 protein, and aneuploidy in patients with benign and malignant fibrous lesions, including 19 with nodular fasciitis (cellular type) (6-88 years old, mean 42.9), 11 with abdominal fibromatoses (22-74 years old, mean 37.9), 13 with extraabdominal fibromatoses (2-38 years old, mean 19.5), and 23 with fibrosarcomas (adult type: 16-71 years old, mean 47.3; infantile type: 3 months to 9 years, mean 2.9) using immunohistochemistry to determine proliferating cell nuclear antigen (PC10) and p53 protein (CM1) as well as performing DNA flow cytometry. The proliferating cell nuclear antigen (PCNA) score was measured as the ratio of PCNA-positive nuclear size/total nuclear size determined by an image analysis computer system. The distribution pattern of the PCNA-positive cells was uneven in each instance of nodular fasciitis, in contrast to the distribution in abdominal fibromatosis, extraabdominal fibromatosis, and fibrosarcoma. Both fibrosarcoma (28.4 +/- 20.0) and nodular fasciitis (33.6 +/- 20.9) exhibited a larger value and a greater variation in the PCNA score than did either abdominal (13.5 +/- 14.5) or extraabdominal fibromatosis (19.9 +/- 21.5). Abdominal fibromatosis exhibited a smaller value and less variation in the score. In short, the PCNA score did not correlate with the malignant potential. The proliferative index (S + G2 + M fraction) in fibrosarcoma was significantly higher than in either nodular fasciitis or abdominal fibromatosis. Aneuploidy was detected in five cases (26%) of fibrosarcoma, while six (26%) fibrosarcomas showed p53 positivity. Furthermore, p53-positive patients had a worse survival (0.01 < p < 0.05), and p53 positivity correlated with the proliferative index (p < 0.01). In conclusion, the PCNA score simply indicates the proliferative activity independent of malignant potential. On the other hand, p53 positivity, proliferative index, and aneuploidy are all indicators of

  16. Proliferation Response to Interleukin-2 and Jak/Stat Activation of T Cells Immortalized by Human T-Cell Lymphotropic Virus Type 1 Is Independent of Open Reading Frame I Expression

    OpenAIRE

    Collins, Nathaniel D.; D’Souza, Celine; Albrecht, Björn; Robek, Michael D.; Ratner, Lee; Ding, Wei; Green, Patrick L.; Lairmore, Michael D.

    1999-01-01

    Human T-cell lymphotropic virus type 1 (HTLV-1), a complex retrovirus, encodes a hydrophobic 12-kD protein from pX open reading frame (ORF) I that localizes to cellular endomembranes and contains four minimal SH3 binding motifs (PXXP). We have demonstrated the importance of ORF I expression in the establishment of infection and hypothesize that p12I has a role in T-cell activation. In this study, we tested interleukin-2 (IL-2) receptor expression, IL-2-mediated proliferation, and Jak/Stat act...

  17. Bezafibrate enhances proliferation and differentiation of osteoblastic MC3T3-E1 cells via AMPK and eNOS activation

    Institute of Scientific and Technical Information of China (English)

    Xing ZHONG; Ling-ling XIU; Guo-hong WEI; Yuan-yuan LIU; Lei SU; Xiao-pei CAO; Yan-bing LI; Hai-peng XIAO

    2011-01-01

    Aim: To investigate the effects of bezafibrate on the proliferation and differentiation of osteoblastic MC3T3-E1 cells, and to determine the signaling pathway underlying the effects.Methods: MC3T3-E1 cells, a mouse osteoblastic cell line, were used. Cell viability and proliferation were examined using MTT assay and colorimetric BrdU incorporation assay, respectively. NO production was evaluated using the Griess reagent. The mRNA expression of ALP, collagen I, osteocalcin, BMP-2, and Runx-2 was measured using real-time PCR. Western blot analysis was used to detect the expression of AMPK and eNOS proteins.Results: Bezafibrate increased the viability and proliferation of MC3T3-E1 cells in a dose- and time-dependent manner. Bezafibrate (100 μmol/L) significantly enhanced osteoblastic mineralization and expression of the differentiation markers ALP, collagen I and osteocalcin. Bezaflbrate (100 μmol/L) increased phosphorylation of AMPK and eNOS, which led to an increase of NO production by 4.08-fold, and upregulating BMP-2 and Runx-2 mRNA expression. These effects could be blocked by AMPK inhibitor compound C (5 μmol/L), or the PPARβ inhibitor GSK0660 (0.5 μmol/L), but not by the PPARa inhibitor MK886 (10 μmol/L). Furthermore, GSK0660, compound C, or N-nitro-L-arginine methyl ester hydrochloride (L-NAME, 1 mmol/L) could reverse the stimulatory effects of bezafibrate (100 pmol/L) on osteoblast proliferation and differentiation, whereas MK886 only inhibited bezafibrate-induced osteoblast prolifera-tion.Conclusion: Bezafibrate stimulates proliferation and differentiation of MC3T3-E1 cells, mainly via a PPARβ-dependent mechanism. The drug might be beneficial for osteoporosis by promoting bone formation.

  18. Monovalent ions control proliferation of Ehrlich Lettre ascites cells

    DEFF Research Database (Denmark)

    Klausen, Thomas Kjaer; Preisler, Sarah; Pedersen, Stine Helene Falsig;

    2010-01-01

    with the pH-sensitive dye BCECF, substitution of Na+ was observed to upregulate the activity of the Na+/H+ exchanger NHE1 as well as of Na+-independent acid extrusion mechanisms, facilitating intracellular pH (pH(i)) recovery after acid loading and increasing pH(i). Results using the potential sensitive dye...... effect. Western blots showed reduced chloride intracellular channel CLIC1 and chloride channel ClC-2 expression in the plasma membrane in S compared with G(1). Our results suggest that Na+ regulates ELA cell proliferation by regulating intracellular pH while Cl(-) may regulate proliferation by fine...

  19. PEROXISOME PROLIFERATOR-ACTIVATED RECEPTORα (PPARα) AGONISTS DIFFERENTIALLY REGULATE INHIBITOR OF DNA BINDING (ID2) EXPRESSION IN RODENTS AND HUMAN CELLS

    Science.gov (United States)

    Abstract Inhibitor of DNA binding (Id2) is a member of the helix-loop-helix (HLH) transcription factor family whose members play important roles in cell differentiation and proliferation. Id2 has been linked to the development of cardiovascular diseases since thiazolidinediones,...

  20. Activating Effect of Benzbromarone, a Uricosuric Drug, on Peroxisome Proliferator-Activated Receptors

    Directory of Open Access Journals (Sweden)

    Chiyoko Kunishima

    2007-01-01

    Full Text Available Benzbromarone, a uricosuric drug, reportedly causes hepatic hypertrophy accompanied by proliferation of peroxisomes in rats. To elucidate the mechanisms underlying induction of peroxisome proliferation by benzbromarone, we examined binding affinity for peroxisome proliferator-activated receptor α (PPARα and γ (PPARγ, and effects on the binding activity of PPARs with peroxisome proliferation-responsive element (PPRE and expression of the PPARs target protein. Binding affinity of benzbromarone for PPARα and PPARγ was examined by reporter gene assay. Binding activity of PPARs with PPRE was determined by electric mobility shift assay, and expression of lipoprotein lipase (LPL and acyl-CoA synthetase (ACS by Western blot method. Benzbromarone displayed affinity for PPARα and PPARγ, and promoted binding of PPARs to PPRE. Furthermore, cultured cells with benzbromarone added showed upregulated expression of LPL and ACS. These results suggest that benzbromarone induces peroxisome proliferation in hepatocytes by binding to PPARs, and controls expression of proteins related to lipid metabolism.

  1. Inhibition of ALK enzymatic activity in T-cell lymphoma cells induces apoptosis and suppresses proliferation and STAT3 phosphorylation independently of Jak3

    DEFF Research Database (Denmark)

    Marzec, Michal; Kasprzycka, Monika; Ptasznik, Andrzej;

    2005-01-01

    Aberrant expression of the ALK tyrosine kinase as a chimeric protein with nucleophosmin (NPM) and other partners plays a key role in malignant cell transformation of T-lymphocytes and other cells. Here we report that two small-molecule, structurally related, quinazoline-type compounds, WHI-131...... and WHI-154, directly inhibit enzymatic activity of NPM/ALK as demonstrated by in vitro kinase assays using a synthetic tyrosine-rich oligopeptide and the kinase itself as the substrates. The inhibition of NPM/ALK activity resulted in malignant T cells in suppression of their growth, induction...... of apoptosis and inhibition of tyrosine phosphorylation of STAT3, the key effector of the NPM/ALK-induced oncogenesis. We also show that the STAT3 tyrosine phosphorylation is mediated in the malignant T cells by NPM/ALK independently of Jak3 kinase as evidenced by the presence of STAT3 phosphorylation...

  2. Simvastatin modulates mesenchymal stromal cell proliferation and gene expression.

    Directory of Open Access Journals (Sweden)

    Dalila Lucíola Zanette

    Full Text Available Statins are widely used hypocholesterolemic drugs that block the mevalonate pathway, responsible for the biosysnthesis of cholesterol. However, statins also have pleiotropic effects that interfere with several signaling pathways. Mesenchymal stromal cells (MSC are a heterogeneous mixture of cells that can be isolated from a variety of tissues and are identified by the expression of a panel of surface markers and by their ability to differentiate in vitro into osteocytes, adipocytes and chondrocytes. MSC were isolated from amniotic membranes and bone marrows and characterized based on ISCT (International Society for Cell Therapy minimal criteria. Simvastatin-treated cells and controls were directly assayed by CFSE (Carboxyfluorescein diacetate succinimidyl ester staining to assess their cell proliferation and their RNA was used for microarray analyses and quantitative PCR (qPCR. These MSC were also evaluated for their ability to inhibit PBMC (peripheral blood mononuclear cells proliferation. We show here that simvastatin negatively modulates MSC proliferation in a dose-dependent way and regulates the expression of proliferation-related genes. Importantly, we observed that simvastatin increased the percentage of a subset of smaller MSC, which also were actively proliferating. The association of MSC decreased size with increased pluripotency and the accumulating evidence that statins may prevent cellular senescence led us to hypothesize that simvastatin induces a smaller subpopulation that may have increased ability to maintain the entire pool of MSC and also to protect them from cellular senescence induced by long-term cultures/passages in vitro. These results may be important to better understand the pleiotropic effects of statins and its effects on the biology of cells with regenerative potential.

  3. Opioid-induced proliferation of vascular endothelial cells

    Directory of Open Access Journals (Sweden)

    Sandra Leo

    2009-05-01

    Full Text Available Sandra Leo1,2, Rony Nuydens1, Theo F Meert11Pain and Neurology, CNS Department, Johnson and Johnson Pharmaceutical Research and Development, a division of Janssen Pharmaceutica N.V, Beerse, Belgium; 2Laboratory of Biological Psychology, University of Leuven, Leuven, BelgiumAbstract: Angiogenesis is an important issue in cancer research and opioids are often used to treat pain in cancer patients. Therefore it is important to know if the use of opioids is associated with an aberrant stimulation of tumor growth triggered by the stimulation of angiogenesis in cancer patients. Some studies in the literature have suggested the presence of the μ3 opioid receptor, known as the receptor for many opioids, on endothelial cells, which are key players in the process of angiogenesis. In this study we used endothelial cells known to express the μ3 opioid receptor (MOR3, to evaluate the effects of morphine on angiogenesis. We first investigated the effect of morphine on the proliferation of endothelial cells. We showed that morphine is able to stimulate vascular endothelial cell proliferation in vitro. This effect of morphine is mediated by the mitogen-activated protein kinase (MAPK pathway as pre-treatment with PD98059 inhibited this excessive proliferation. Because previous studies indicated nitric oxide (NO as a downstream messenger we investigated the role of NO in the aberrant proliferation of endothelial cells. Our data could not confirm these findings using intracellular NO measurements and quantitative fluorescence microscopy. The potential use and pitfalls of opioids in cancer patients is discussed in light of these negative findings. Keywords: endothelial cells, morphine, cell proliferation, MAPK, nitric oxide, μ3 opioid receptor, angiogenesis

  4. Matrix stiffness regulates endothelial cell proliferation through septin 9.

    Directory of Open Access Journals (Sweden)

    Yi-Ting Yeh

    Full Text Available Endothelial proliferation, which is an important process in vascular homeostasis, can be regulated by the extracellular microenvironment. In this study we demonstrated that proliferation of endothelial cells (ECs was enhanced on hydrogels with high stiffness (HSG, 21.5 kPa in comparison to those with low stiffness (LSG, 1.72 kPa. ECs on HSG showed markedly prominent stress fibers and a higher RhoA activity than ECs on LSG. Blockade of RhoA attenuated stress fiber formation and proliferation of ECs on HSG, but had little effect on ECs on LSG; enhancement of RhoA had opposite effects. The phosphorylations of Src and Vav2, which are positive RhoA upstream effectors, were higher in ECs on HSG. The inhibition of Src/Vav2 attenuated the HSG-mediated RhoA activation and EC proliferation but exhibited nominal effects on ECs on LSG. Septin 9 (SEPT9, the negative upstream effector for RhoA, was significantly higher in ECs on LSG. The inhibition of SEPT9 increased RhoA activation, Src/Vav2 phosphorylations, and EC proliferation on LSG, but showed minor effects on ECs on HSG. We further demonstrated that the inactivation of integrin α(vβ(3 caused an increase of SEPT9 expression in ECs on HSG to attenuate Src/Vav2 phosphorylations and inhibit RhoA-dependent EC proliferation. These results demonstrate that the SEPT9/Src/Vav2/RhoA pathway constitutes an important molecular mechanism for the mechanical regulation of EC proliferation.

  5. Matrix Stiffness Regulates Endothelial Cell Proliferation through Septin 9

    Science.gov (United States)

    Yeh, Yi-Ting; Hur, Sung Sik; Chang, Joann; Wang, Kuei-Chun; Chiu, Jeng-Jiann; Li, Yi-Shuan; Chien, Shu

    2012-01-01

    Endothelial proliferation, which is an important process in vascular homeostasis, can be regulated by the extracellular microenvironment. In this study we demonstrated that proliferation of endothelial cells (ECs) was enhanced on hydrogels with high stiffness (HSG, 21.5 kPa) in comparison to those with low stiffness (LSG, 1.72 kPa). ECs on HSG showed markedly prominent stress fibers and a higher RhoA activity than ECs on LSG. Blockade of RhoA attenuated stress fiber formation and proliferation of ECs on HSG, but had little effect on ECs on LSG; enhancement of RhoA had opposite effects. The phosphorylations of Src and Vav2, which are positive RhoA upstream effectors, were higher in ECs on HSG. The inhibition of Src/Vav2 attenuated the HSG-mediated RhoA activation and EC proliferation but exhibited nominal effects on ECs on LSG. Septin 9 (SEPT9), the negative upstream effector for RhoA, was significantly higher in ECs on LSG. The inhibition of SEPT9 increased RhoA activation, Src/Vav2 phosphorylations, and EC proliferation on LSG, but showed minor effects on ECs on HSG. We further demonstrated that the inactivation of integrin αvβ3 caused an increase of SEPT9 expression in ECs on HSG to attenuate Src/Vav2 phosphorylations and inhibit RhoA-dependent EC proliferation. These results demonstrate that the SEPT9/Src/Vav2/RhoA pathway constitutes an important molecular mechanism for the mechanical regulation of EC proliferation. PMID:23118862

  6. Danhong inhibits oxidized low-density lipoprotein-induced immune maturation of dentritic cells via a peroxisome proliferator activated receptor γ-mediated pathway.

    Science.gov (United States)

    Liu, Hongying; Wang, Shijun; Sun, Aijun; Huang, Dong; Wang, Wei; Zhang, Chunyu; Shi, Dazhuo; Chen, Keji; Zou, Yunzeng; Ge, Junbo

    2012-01-01

    Danhong injection (DHI), a Chinese Materia Medica standardized product extracted from Radix Salviae miltiorrhizae and Flos Carthami tinctorii, is effective in the treatment of atherosclerosis (AS)-related diseases. It is widely recognized that AS is a complex inflammatory disease of the arterial wall and the dendritic cells (DCs) is a major player in the pathogenesis of AS via mediating atherosclerotic antigen presenting and T lymphocytes. Here, we determined the effect and possible mechanism of DHI on oxidized low-density lipoprotein (ox-LDL)-induced maturation and immune function of DCs. Human monocyte-derived DCs were incubated with DHI or ciglitazone and were subsequently stimulated with ox-LDL to induce maturation. Similar to ciglitazone, a peroxisome proliferator activated receptor (PPAR) γ agonist, DHI, could significantly reduce ox-LDL-induced expressions of mature markers, enhance the endocytotic function, and inhibit secretions of cytokine on DCs. These effects of DHI could be partly reversed by silencing the PPARγ. In conclusion, DHI could inhibit ox-LDL-induced maturation of DCs partly through activating a PPARγ-mediated signaling pathway.

  7. Kaposi's Sarcoma-Associated Herpesvirus (KSHV) vIL-6 Promotes Cell Proliferation and Migration by Upregulating DNMT1 via STAT3 Activation

    OpenAIRE

    Jing Wu; Yuqiao Xu; Dongping Mo; Peijun Huang; Ruihong Sun; Lei Huang; Shiyang Pan; Jian Xu

    2014-01-01

    Kaposi's sarcoma-associated herpesvirus (KSHV) is etiologically associated with Kaposi's sarcoma (KS), the most common AIDS-related malignancy. KSHV vIL-6 promotes KS development, but the exact mechanisms remain unclear. Here, we reported that KSHV vIL-6 enhanced the expression of DNA methyltransferase 1 (DNMT1) in endothelial cells,increased the global genomic DNA methylation, and promoted cell proliferation and migration. And this effect could be blocked by the DNA methyltransferase inhibit...

  8. Mal/SRF is dispensable for cell proliferation in Drosophila.

    Directory of Open Access Journals (Sweden)

    Barry J Thompson

    Full Text Available The Mal/SRF transcription factor is regulated by the level of G-actin in cells and has important roles in cell migration and other actin-dependent processes in Drosophila. A recent report suggests that Mal/SRF and an upstream regulator, Pico, are required for cell proliferation and tissue growth in Drosophila. I find otherwise. Mutation of Mal or SRF does not affect cell proliferation in the fly wing. Furthermore, I cannot reproduce the reported effects of Pico RNAi or Pico overexpression on body size. Nevertheless, I can confirm that overexpression of Pico or Mal causes tissue overgrowth specifically in the fly wing--where SRF is most highly expressed. My results indicate that Mal/SRF can promote tissue growth when abnormally active, but is not normally required for tissue growth during development.

  9. The ubiquitin ligase HectH9 regulates transcriptional activation by Myc and is essential for tumor cell proliferation

    DEFF Research Database (Denmark)

    Adhikary, Sovana; Marinoni, Federica; Hock, Andreas;

    2005-01-01

    The Myc oncoprotein forms a binary activating complex with its partner protein, Max, and a ternary repressive complex that, in addition to Max, contains the zinc finger protein Miz1. Here we show that the E3 ubiquitin ligase HectH9 ubiquitinates Myc in vivo and in vitro, forming a lysine 63-linke...

  10. Roles of Nrf2 in cell proliferation and differentiation.

    Science.gov (United States)

    Murakami, Shohei; Motohashi, Hozumi

    2015-11-01

    The Keap1-Nrf2 system plays pivotal roles in defense mechanisms by regulating cellular redox homeostasis. Nrf2 is an inducible transcription factor that activates a battery of genes encoding antioxidant proteins and phase II enzymes in response to oxidative stress and electrophilic xenobiotics. The activity of Nrf2 is regulated by Keap1, which promotes the ubiquitination and subsequent degradation of Nrf2 under normal conditions and releases the inhibited Nrf2 activity upon exposure to the stresses. Though an impressive contribution of the Keap1-Nrf2 system to the protection from exogenous and endogenous electrophilic insults has been well established, a line of evidence has suggested that the Keap1-Nrf2 system has various novel functions, particularly in cell proliferation and differentiation. Because the proliferation and differentiation of diverse cell types are often influenced and modulated by the cellular redox balance, Nrf2 has been considered to control these cellular processes by regulating the cellular levels of reactive oxygen species (ROS). In addition, analyses of the genome-wide distribution of Nrf2 have identified new sets of Nrf2 target genes whose products are involved in cell proliferation and differentiation but not necessarily in the regulation of oxidative stress. Considering the most characteristic features of Nrf2 as an inducible transcription factor, a newly emerged concept proposes that the Keap1-Nrf2 system translates environmental stresses into regulatory network signals in cell fate determination. In this review, we introduce the contribution of Nrf2 to lineage-specific differentiation, maintenance and differentiation of stem cells, and proliferation of normal and cancer cells, and we discuss how the response to fluctuating environments modulates cell behavior through the Keap1-Nrf2 system. PMID:26119783

  11. Short-Chain Fatty Acids Stimulate Angiopoietin-Like 4 Synthesis in Human Colon Adenocarcinoma Cells by Activating Peroxisome Proliferator-Activated Receptor γ

    DEFF Research Database (Denmark)

    Alex, Sheril; Lange, Katja; Amolo, Tom;

    2013-01-01

    with the notion that fermentation leads to PPAR activation in vivo, feeding mice a diet rich in inulin induced PPAR target genes and pathways in the colon. We conclude that (i) SCFA potently stimulate ANGPTL4 synthesis in human colon adenocarcinoma cells and (ii) SCFA transactivate and bind to PPARγ. Our data...

  12. Cell Proliferation Tracking Using Graphene Sensor Arrays

    Directory of Open Access Journals (Sweden)

    Ronan Daly

    2012-01-01

    Full Text Available The development of a novel label-free graphene sensor array is presented. Detection is based on modification of graphene FET devices and specifically monitoring the change in composition of the nutritive components in culturing medium. Micro-dispensing of Escherichia coli in medium shows feasibility of accurate positioning over each sensor while still allowing cell proliferation. Graphene FET device fabrication, sample dosing, and initial electrical characterisation have been completed and show a promising approach to reducing the sample size and lead time for diagnostic and drug development protocols through a label-free and reusable sensor array fabricated with standard and scalable microfabrication technologies.

  13. Liver epithelial cells inhibit proliferation and invasiveness of hepatoma cells.

    Science.gov (United States)

    Jeng, Kuo-Shyang; Jeng, Chi-Juei; Jeng, Wen-Juei; Sheen, I-Shyan; Li, Shih-Yun; Hung, Zih-Hang; Hsiau, Hsin-I; Yu, Ming-Che; Chang, Chiung-Fang

    2016-03-01

    Hepatocellular carcinoma (HCC) is a worldwide malignancy with poor prognosis. Liver progenitors or stem cells could be a potential therapy for HCC treatment since they migrate toward tumors. Rat liver epithelial (RLE) cells have both progenitor and stem cell-like properties. Therefore, our study elucidated the therapeutic effect of RLE cells in rat hepatoma cells. RLE cells were isolated from 10-day old rats and characterized for stem cell marker expression. RLE cells and rat hepatoma cells (H4-IIE-C3 cells) were co-cultured and divided into four groups with different ratios of RLE and hepatoma cells. Group A had only rat hepatoma cells as a control group. The ratios of rat hepatoma and RLE cells in group B, C and D were 5:1, 1:1 and 1:5, respectively. Effective inhibition of cell proliferation and migration was found in group D when compared to group A. There was a significant decrease in Bcl2 expression and increase in late apoptosis of rat hepatoma cells when adding more RLE cells. RLE cells reduced cell proliferation and migration of rat hepatoma cells. These results suggested that RLE cells could be used as a potential cell therapy. PMID:26647726

  14. Inhibitory Effect of Cantharidin on Proliferation of A549 Cells

    Institute of Scientific and Technical Information of China (English)

    WANG Xiao-hua; YIN Yuan-qin; SUI Cheng-guang; MENG Fan-dong; MA Ping; JIANG You-hong

    2007-01-01

    Objective: To study the inhibition of Cantharidin against the proliferation of human lung cancer A549 cells and its mechanism. Methods: MTT assay was employed to determine the inhibition of Cantharidin against proliferation of A549 cells and flow Cytometry was applied to analyze A549 cell cycle and the effect of Cantharidin on cell cycle. Results: Cantharidin showed inhibition against the proliferation of A549 cells, and the inhibition was mediated by blocking A549 cell cycle at G2/M phase significantly. Conclusion: Cantharidin exhibits inhibition against the proliferation of human lung cancer A549 cells.

  15. Coordinate reduction in cell proliferation and cell death in mouse olfactory epithelium from birth to maturity

    NARCIS (Netherlands)

    Fung, KM; Peringa, J; Venkatachalam, S; Lee, VMY; Trojanowski, JQ

    1997-01-01

    We investigated cell proliferation and cell death in the olfactory epithelium (OE) of mice from birth to maturity using bromodeoxyuridine and terminal deoxynucleotidyl transferase nick end labeling. We show that cell death events and proliferative activity diminish concomitantly with age in the OE.

  16. Quantitative analysis of in vivo cell proliferation.

    Science.gov (United States)

    Cameron, Heather A

    2006-11-01

    Injection and immunohistochemical detection of 5-bromo-2'-deoxyuridine (BrdU) has become the standard method for studying the birth and survival of neurons, glia, and other cell types in the nervous system. BrdU, a thymidine analog, becomes stably incorporated into DNA during the S-phase of mitosis. Because DNA containing BrdU can be specifically recognized by antibodies, this method allows dividing cells to be marked at any given time and then identified at time points from a few minutes to several years later. BrdU immunohistochemistry is suitable for cell counting to examine the regulation of cell proliferation and cell fate. It can be combined with labeling by other antibodies, allowing confocal analysis of cell phenotype or expression of other proteins. The potential for nonspecific labeling and toxicity are discussed. Although BrdU immunohistochemistry has almost completely replaced tritiated thymidine autoradiography for labeling dividing cells, this method and situations in which it is still useful are also described. PMID:18428635

  17. Simvastatin suppresses breast cancer cell proliferation induced by senescent cells

    NARCIS (Netherlands)

    Liu, Su; Uppal, Harpreet; Demaria, Marco; Desprez, Pierre-Yves; Campisi, Judith; Kapahi, Pankaj

    2015-01-01

    Cellular senescence suppresses cancer by preventing the proliferation of damaged cells, but senescent cells can also promote cancer though the pro-inflammatory senescence-associated secretory phenotype (SASP). Simvastatin, an HMG-coA reductase inhibitor, is known to attenuate inflammation and preven

  18. Modeling Nonalcoholic Fatty Liver Disease with Human Pluripotent Stem Cell-Derived Immature Hepatocyte-Like Cells Reveals Activation of PLIN2 and Confirms Regulatory Functions of Peroxisome Proliferator-Activated Receptor Alpha

    Science.gov (United States)

    Graffmann, Nina; Ring, Sarah; Kawala, Marie-Ann; Wruck, Wasco; Ncube, Audrey; Trompeter, Hans-Ingo

    2016-01-01

    Nonalcoholic fatty liver disease (NAFLD/steatosis) is a metabolic disease characterized by the incorporation of fat into hepatocytes. In this study, we developed an in vitro model for NAFLD based on hepatocyte-like cells (HLCs) differentiated from human pluripotent stem cells. We induced fat storage in these HLCs and detected major expression changes of metabolism-associated genes, as well as an overall reduction of liver-related microRNAs. We observed an upregulation of the lipid droplet coating protein Perilipin 2 (PLIN2), as well as of numerous genes of the peroxisome proliferator-activated receptor (PPAR) pathway, which constitutes a regulatory hub for metabolic processes. Interference with PLIN2 and PPARα resulted in major alterations in gene expression, especially affecting lipid, glucose, and purine metabolism. Our model recapitulates many metabolic changes that are characteristic for NAFLD. It permits the dissection of disease-promoting molecular pathways and allows us to investigate the influences of distinct genetic backgrounds on disease progression. PMID:27308945

  19. Sirtuin1 promotes osteogenic differentiation through downregulation of peroxisome proliferator-activated receptor γ in MC3T3-E1 cells.

    Science.gov (United States)

    Qu, Bo; Ma, Yuan; Yan, Ming; Gong, Kai; Liang, Feng; Deng, Shaolin; Jiang, Kai; Ma, Zehui; Pan, Xianming

    2016-09-01

    Osteoporosis is a skeletal disorder characterized by bone loss, resulting in architectural deterioration of the skeleton, decreased bone strength and an increased risk of fragility fractures. Strengthening osteogenesis is an effective way to relieve osteoporosis. Sirtuin1 (Sirt1) is a nicotinamide adenine dinucleotide (NAD(+))-dependent deacetylase, which is reported to be involved in improving osteogenesis. Sirt1 targets peroxisome proliferator-activated receptor γ (PPARγ) in the regulation of adipose tissues; however, the molecular mechanism of Sirt1 in osteogenic differentiation is still unknown. PPARγ tends to induce more adipogenic differentiation rather than osteogenic differentiation. Hence, we hypothesized that Sirt1 facilitates osteogenic differentiation through downregulation of PPARγ signaling. Mouse pre-osteoblastic MC3T3-E1 cells were cultured under osteogenic medium. Sirt1 was overexpressed through plasmid transfection. The results showed that high expression of Sirt1 was associated with increased osteogenic differentiation, as indicated by quantitative PCR and Western blot analysis of osteogenic markers, and Von Kossa staining. Sirt1 overexpression also directly and negatively regulated the expression of PPARγ and its downstream molecules. Use of the PPARγ agonist Rosiglitazone, reversed the effects of Sirt1 on osteogenic differentiation. Using constructed luciferase plasmids, we demonstrated a role of Sirt1 in inhibiting PPARγ-induced activity and expression of adipocyte-specific genes, including acetyl-coenzyme A carboxylase (Acc) and fatty acid binding protein 4 (Fabp4). The interaction between Sirt1 and PPARγ was further confirmed using co-immunoprecipitation analysis. Together, these results reveal a novel mechanism for Sirt1 in osteogenic differentiation through downregulation of PPARγ activity. These findings suggest that the Sirt1-PPARγ pathway may represent a potential target for enhancement of osteogenesis and treatment of

  20. Nifedipine, a calcium channel blocker, inhibits advanced glycation end product (AGE)-elicited mesangial cell damage by suppressing AGE receptor (RAGE) expression via peroxisome proliferator-activated receptor-gamma activation

    International Nuclear Information System (INIS)

    The interaction between advanced glycation end products (AGE) and their receptor RAGE mediates the progressive alteration in renal architecture and loss of renal function in diabetic nephropathy. Oxidative stress generation and inflammation also play a central role in diabetic nephropathy. This study investigated whether and how nifedipine, a calcium channel blocker (CCB), blocked the AGE-elicited mesangial cell damage in vitro. Nifedipine, but not amlodipine, a control CCB, down-regulated RAGE mRNA levels and subsequently reduced reactive oxygen species (ROS) generation in AGE-exposed mesangial cells. AGE increased mRNA levels of vascular cell adhesion molecule-1 (VCAM-1) and induced monocyte chemoattractant protein-1 (MCP-1) production in mesangial cells, both of which were prevented by the treatment with nifedipine, but not amlodipine. The beneficial effects of nifedipine on AGE-exposed mesangial cells were blocked by the simultaneous treatment of GW9662, an inhibitor of peroxisome proliferator-activated receptor-γ (PPAR-γ). Although nifedipine did not affect expression levels of PPAR-γ, it increased the PPAR-γ transcriptional activity in mesangial cells. Our present study provides a unique beneficial aspect of nifedipine on diabetic nephropathy; it could work as an anti-inflammatory agent against AGE by suppressing RAGE expression in cultured mesangial cells via PPAR-γ activation.

  1. Peroxisomes in Different Skeletal Cell Types during Intramembranous and Endochondral Ossification and Their Regulation during Osteoblast Differentiation by Distinct Peroxisome Proliferator-Activated Receptors.

    Directory of Open Access Journals (Sweden)

    Guofeng Qian

    Full Text Available Ossification defects leading to craniofacial dysmorphism or rhizomelia are typical phenotypes in patients and corresponding knockout mouse models with distinct peroxisomal disorders. Despite these obvious skeletal pathologies, to date no careful analysis exists on the distribution and function of peroxisomes in skeletal tissues and their alterations during ossification. Therefore, we analyzed the peroxisomal compartment in different cell types of mouse cartilage and bone as well as in primary cultures of calvarial osteoblasts. The peroxisome number and metabolism strongly increased in chondrocytes during endochondral ossification from the reserve to the hypertrophic zone, whereas in bone, metabolically active osteoblasts contained a higher numerical abundance of this organelle than osteocytes. The high abundance of peroxisomes in these skeletal cell types is reflected by high levels of Pex11β gene expression. During culture, calvarial pre-osteoblasts differentiated into secretory osteoblasts accompanied by peroxisome proliferation and increased levels of peroxisomal genes and proteins. Since many peroxisomal genes contain a PPAR-responsive element, we analyzed the gene expression of PPARɑ/ß/ɣ in calvarial osteoblasts and MC3T3-E1 cells, revealing higher levels for PPARß than for PPARɑ and PPARɣ. Treatment with different PPAR agonists and antagonists not only changed the peroxisomal compartment and associated gene expression, but also induced complex alterations of the gene expression patterns of the other PPAR family members. Studies in M3CT3-E1 cells showed that the PPARß agonist GW0742 activated the PPRE-mediated luciferase expression and up-regulated peroxisomal gene transcription (Pex11, Pex13, Pex14, Acox1 and Cat, whereas the PPARß antagonist GSK0660 led to repression of the PPRE and a decrease of the corresponding mRNA levels. In the same way, treatment of calvarial osteoblasts with GW0742 increased in peroxisome number and

  2. Nfkb1 activation by the E26 transformation-specific transcription factors PU.1 and Spi-B promotes Toll-like receptor-mediated splenic B cell proliferation.

    Science.gov (United States)

    Li, Stephen K H; Abbas, Ali K; Solomon, Lauren A; Groux, Gaëlle M N; DeKoter, Rodney P

    2015-05-01

    Generation of antibodies against T-independent and T-dependent antigens requires Toll-like receptor (TLR) engagement on B cells for efficient responses. However, the regulation of TLR expression and responses in B cells is not well understood. PU.1 and Spi-B (encoded by Sfpi1 and Spib, respectively) are transcription factors of the E26 transformation-specific (ETS) family and are important for B cell development and function. It was found that B cells from mice knocked out for Spi-B and heterozygous for PU.1 (Sfpi1(+/-) Spib(-/-) [PUB] mice) proliferated poorly in response to TLR ligands compared to wild-type (WT) B cells. The NF-κB family member p50 (encoded by Nfkb1) is required for lipopolysaccharide (LPS) responsiveness in mice. PUB B cells expressed reduced Nfkb1 mRNA transcripts and p50 protein. The Nfkb1 promoter was regulated directly by PU.1 and Spi-B, as shown by reporter assays and chromatin immunoprecipitation analysis. Occupancy of the Nfkb1 promoter by PU.1 was reduced in PUB B cells compared to that in WT B cells. Finally, infection of PUB B cells with a retroviral vector encoding p50 substantially restored proliferation in response to LPS. We conclude that Nfkb1 transcriptional activation by PU.1 and Spi-B promotes TLR-mediated B cell proliferation.

  3. Adipogenesis licensing and execution are disparately linked to cell proliferation

    Institute of Scientific and Technical Information of China (English)

    Wei Guo; Kun-Ming Zhang; Kang Tu; Yi-Xue Li; Li Zhu; Hua-Sheng Xiao; Ying Yang; Jia-Rui Wu

    2009-01-01

    Coordination of cell differentiation and proliferation is a key issue in the development process of multi-cellular organisms and stem cells. Here we provide evidence that the establishment of adipocyte differentiation of 3T3-LI cells requires two processes: the licensing of an adipogenesis gene-expression program within a particular growth-arrest stage, i.e., the contact-inhibition stage, and then the execution of this program in a cell-cycle-independent manner,by which the licensed progenitors are differentiated into adipocytes in the presence of inducing factors. Our results showed that differentiation licensing of 3T3-L1 cells during the contact-inhibition stage involved epigenetic modifications such as DNA methylation and histone modifications, whereas disturbing these epigenetic modifications by DNA methylation inhibitors or RNAi during the contact-inhibition stage significantly reduced adipogenesis efficiency.More importantly, when these licensed 3T3-LI cells were re-cultured under non-differentiating conditions or treated only with insulin, this adipogenesis commitment could be maintained from one cell generation to the next, whereby the licensed program could be activated in a cell-cycle-independent manner once these cells were subjected to adipogenesis-inducing conditions. This result suggests that differentiation licensing and differentiation execution can be uncoupled and disparately linked to cell proliferation. Our findings deliver a new concept that cell-fate decision can be subdivided into at least two stages, licensing and execution, which might have different regulatory relationships with cell proliferation, in addition, this new concept may provide a clue for developing new strategies against obesity.

  4. Comparative studies on the chemical and cell-based antioxidant activities and antitumor cell proliferation properties of soy milk manufactured by conventional and commercial UHT methods.

    Science.gov (United States)

    Xu, Baojun; Chang, Sam K C; Liu, Zhisheng; Yuan, Shaohong; Zou, Yanping; Tan, Yingying

    2010-03-24

    The aims of this work were to compare antiproliferation, antioxidant activities and total phytochemicals and individual isoflavone profiles in soy milk processed by various methods including traditional stove cooking, direct steam injection, direct ultrahigh temperature (UHT), indirect UHT, and a two-stage simulated industry method, and a selected commercial soy milk product. Various processing methods significantly affected total saponin, phytic acid, and total phenolic content and individual isoflavone distribution. The laboratory UHT and the two-stage processed soy milk exhibited relatively higher total phenolic content, total flavonoid content, saponin and phytic acid than those processed by the traditional and steam processed methods. Thermal processing caused obvious intertransformation but did not cause severe degradation except for breaking down of aglycons. Thermal processing significantly increased antioxidant capacities of soy milk determined by chemical analyses, but decreased cellular antioxidant capacities as compared to the raw soy milk. The raw and all processed soy milk exhibited antipoliferative activities against human HL-60 leukemia cells, AGS gastric tumor cells, and DU145 prostate cancer cells in a dose-dependent manner. The raw soy milk, but not the processed soy milk, exhibited a dose-dependent antiproliferative effect against colorectal adenocarcinoma Caco-2 cells. Taken together, these results indicate that various thermal processing methods change not only phytochemcials but also potential health-promoting effects of soy milk.

  5. Nifedipine promotes the proliferation and migration of breast cancer cells.

    Directory of Open Access Journals (Sweden)

    Dong-Qing Guo

    Full Text Available Nifedipine is widely used as a calcium channel blocker (CCB to treat angina and hypertension,but it is controversial with respect the risk of stimulation of cancers. In this study, we demonstrated that nifedipine promoted the proliferation and migration of breast cancer cells both invivo and invitro. However, verapamil, another calcium channel blocker, didn't exert the similar effects. Nifedipine and high concentration KCl failed to alter the [Ca2+]i in MDA-MB-231 cells, suggesting that such nifedipine effect was not related with calcium channel. Moreover, nifedipine decreased miRNA-524-5p, resulting in the up-regulation of brain protein I3 (BRI3. Erk pathway was consequently activated and led to the proliferation and migration of breast cancer cells. Silencing BRI3 reversed the promoting effect of nifedipine on the breast cancer. In a summary, nifedipine stimulated the proliferation and migration of breast cancer cells via the axis of miRNA-524-5p-BRI3-Erk pathway independently of its calcium channel-blocking activity. Our findings highlight that nifedipine but not verapamil is conducive for breast cancer growth and metastasis, urging that the caution should be taken in clinic to prescribe nifedipine to women who suffering both hypertension and breast cancer, and hypertension with a tendency in breast cancers.

  6. Melatonin influences proliferation and differentiation of rat dental papilla cells in vitro and dentine formation in vivo by altering mitochondrial activity

    OpenAIRE

    Liu, Jie; Zhou, Hongyu; Fan, Wenguo; DONG, WEIGUO; Fu, Shenli; He, Hongwen; Huang, Fang

    2012-01-01

    Melatonin mediates a variety of biological processes ranging from the control of circadian rhythms to immune regulation. Melatonin also influences bone formation and osteointegration of dental implants. However, the effects of melatonin on dentine formation have not been examined. This study investigated the effects of melatonin on the proliferation and differentiation of rat dental papilla cells (rDPCs) in vitro and dentine formation in vivo. We found that melatonin (0, 10−12, 10−10,10−8 m) ...

  7. Effect of active fraction of Eriocaulon sieboldianum on human leukemia K562 cells via proliferation inhibition, cell cycle arrest and apoptosis induction.

    Science.gov (United States)

    Fan, Yanhua; Lu, Hongyuan; An, Li; Wang, Changli; Zhou, Zhipeng; Feng, Fan; Ma, Hongda; Xu, Yongnan; Zhao, Qingchun

    2016-04-01

    Eriocaulon sieboldianum (Sieb. & Zucc. ex Steud.), a genus of Eriocaulon in the Eriocaulaceae family, is an edible and medicinal plant used in traditional Chinese medicine. It was processed into healthcare beverages for expelling wind-heat, protecting eyes, and reducing blood fat. Also, it has been used with other herbs as Traditional Chinese herbal compound to treat cancer as adjuvants in tumor therapy in China. However, the active fractions and precise cellular mechanisms of E. sieboldianum extract remain to be illustrated. The goal of this study was to investigate the effects of the active fraction of E. sieboldianum on the growth of K562 cells and understand the possible mechanisms of its action. Our findings suggested that the fraction E3 of E. sieboldianum could effectively inhibit the activity of Aurora kinase and induce apoptosis via blocking cell cycle, up-regulating the expression of proapoptotic proteins including p53 and Bax and reducing the expression of Bcl-2. The levels of Cytochrome C, cleaved caspase-9, cleaved caspase-3 and cleaved PARP were also found to be increased after treatment with fraction E3 of E. sieboldianum. This study could improve the development of E. sieboldianum and raise its application value in cancer adjuvant therapy. Considering it is both a dietary supplement and a traditional Chinese herbal medicine which exhibits anticancer activities, it can be developed into functional food. PMID:26923230

  8. Proliferating cell nuclear antigen: a marker for hepatocellular proliferation in rodents.

    OpenAIRE

    Eldrige, S R; Butterworth, B E; Goldsworthy, T L

    1993-01-01

    Two different markers for quantitating cell proliferation were evaluated in livers of control and chemically treated mice and rats. Proliferating cell nuclear antigen (PCNA), an endogenous cell replication marker, and bromodeoxyuridine (BrdU), an exogenously administered DNA precursor label, were detected in formalin-fixed, paraffin-embedded tissues using immunohistochemical techniques. The percentage of cells in S phase (labeling indexes, LI) evaluated as PCNA- or BrdU-positive hepatocellula...

  9. Evaluation of germ-cell kinetics in infertile patients with proliferating cell nuclear antigen proliferating index

    Institute of Scientific and Technical Information of China (English)

    Li ZENG; Xiang-Tian KONG; Jin-Wei SU; Tong-Li XIA; Yan-Qun NA; Ying-Lu GUO

    2001-01-01

    To explore the usefulness of proliferating cell nuclear antigen proliferating index (PCNA PI) in the pathological diagnosis and treatment of male infertility. Methods: Testicular biopsy specimen obtained from 48 cases of male infertility and 2 normal controls were fixed and embedded. The sections were stained with anti-PCNA monoclonal antibodies or haematoxylin/eosin. Proliferating index (PI), expressed as the percentage of germ-cell nuclei positively stained with PCNA antibody, was assessed from more than 20 seminiferous tubules or 600 germ-cells. Results: The infertile patients were divided into 4 groups: Group 1, normal spermatogenesis ( 14 cases); Group 2, hypospermatogenesis (16 cases); Group 3, germinal arrest (10 cases); Group 4, Sertoli cell only syndrome (8 cases). The PCNA PI of normal control testis was 86.5% (mean value). Group 3 had a significantly lower PCNA PI (29.8%) than normal testis; Group 1 and 2 had similar Pis (82.3% and 82.3%, respectively) as the control testis. PI of the negative control (Group 4) was 0 as no germ-cells were found. Conclusion: PCNA PI is useful for assessing germ-cell kinetics, especially for pathological diagnosis of germinal arrest which is difficult to differentiate by routine HE staining technique. In germinal arrest, there is a significantly lowered PCNA PI, which is an indication of DNA synthesis deterioration, suggesting the use of therapies be different from those for hypospermatogenesis.

  10. Piperlongumine Suppresses Proliferation of Human Oral Squamous Cell Carcinoma through Cell Cycle Arrest, Apoptosis and Senescence

    OpenAIRE

    San-Yuan Chen; Geng-Hung Liu; Wen-Ying Chao; Chung-Sheng Shi; Ching-Yen Lin; Yun-Ping Lim; Chieh-Hsiang Lu; Peng-Yeh Lai; Hau-Ren Chen; Ying-Ray Lee

    2016-01-01

    Oral squamous cell carcinoma (OSCC), an aggressive cancer originating in the oral cavity, is one of the leading causes of cancer deaths in males worldwide. This study investigated the antitumor activity and mechanisms of piperlongumine (PL), a natural compound isolated from Piper longum L., in human OSCC cells. The effects of PL on cell proliferation, the cell cycle, apoptosis, senescence and reactive oxygen species (ROS) levels in human OSCC cells were investigated. PL effectively inhibited ...

  11. Role of interleukin in human natural killer cell proliferation

    International Nuclear Information System (INIS)

    Human NK cells, defined by the antibody B73.1, can be induced to proliferate in vitro in the presence of an IL-2 containing conditioned medium (CM) and an irradiated lymphoblastoid line, Daudi. Proliferating NK cells maintain phenotypic and functional characteristics of resting NK cells while newly expressing surface activation antigens (HLA-DR, transferrin receptor, and IL-2 receptor recognized by anti-TAC antibody). A goat anti-IL-2 antiserum and the anti-TAC monoclonal antibody completely block 3H-TdR incorporation in NK cells stimulated with CM alone or with irradiated Daudi cells. Inhibition is also observed when the antibodies are added up to day 4 of culture, indicating that IL-2 is required for both initiation and maintenance of proliferation. Human recombinant IL-2, either alone or with irradiated lymphoblastoid cells, replaces the CM in initiating 3H-TdR incorporation. In limiting dilution analysis the frequency of B73.1 (+) cells responding to rIL-2 is approximately 1/2000 and it is increased ten to thirty fold with the addition of irradiated Daudi cells to the cultures. Cultures stimulated with rIL-2 in the presence of colchicine, show a significant proportion of B73.1 + cells entering cycle each day during the first 3 days. These data show that a significant proportion of resting NK cells are capable of responding to IL-2 and that this response can occur over a period of several days after initiation of cultures

  12. Notch signaling modulates proliferation and differentiation of intestinal crypt base columnar stem cells

    OpenAIRE

    VanDussen, Kelli L; Carulli, Alexis J.; Keeley, Theresa M.; Patel, Sanjeevkumar R.; Puthoff, Brent J.; Magness, Scott T.; Tran, Ivy T.; Maillard, Ivan; Siebel, Christian; Kolterud, Åsa; Grosse, Ann S.; Gumucio, Deborah L; Ernst, Stephen A.; Tsai, Yu-Hwai; Dempsey, Peter J.

    2012-01-01

    Notch signaling is known to regulate the proliferation and differentiation of intestinal stem and progenitor cells; however, direct cellular targets and specific functions of Notch signals had not been identified. We show here in mice that Notch directly targets the crypt base columnar (CBC) cell to maintain stem cell activity. Notch inhibition induced rapid CBC cell loss, with reduced proliferation, apoptotic cell death and reduced efficiency of organoid initiation. Furthermore, expression o...

  13. Inhibition of cell proliferation and induction of apoptosis by oleanane triterpenoid (CDDO-Me) in pancreatic cancer cells is associated with the suppression of hTERT gene expression and its telomerase activity

    Energy Technology Data Exchange (ETDEWEB)

    Deeb, Dorrah; Gao, Xiaohua; Liu, Yongbo [Department of Surgery, Henry Ford Health System, Detroit, MI (United States); Kim, Sahn-Ho [Department of Urology, Henry Ford Health System, Detroit, MI (United States); Pindolia, Kirit R. [Department of Medical Genetics, Henry Ford Health System, Detroit, MI (United States); Arbab, Ali S. [Department of Radiology, Henry Ford Health System, Detroit, MI (United States); Gautam, Subhash C., E-mail: sgautam1@hfhs.org [Department of Surgery, Henry Ford Health System, Detroit, MI (United States)

    2012-06-15

    Highlights: Black-Right-Pointing-Pointer CDDO-Me inhibits hTERT gene expression. Black-Right-Pointing-Pointer CDDO-Me inhibits hTERT protein expression. Black-Right-Pointing-Pointer CDDO-Me inhibits hTERT telomerase activity. Black-Right-Pointing-Pointer CDDO-Me inhibits hTERT regulatory proteins. -- Abstract: Methyl-2-cyano-3,12-dioxooleana-1,9(11)-dien-28-oate (CDDO-Me) is a multifunctional oleanane synthetic triterpenoid with potent anti-inflammatory and antitumorigenic properties. The mechanisms of the antisurvival and apoptosis-inducing activities of CDDO-Me and related derivatives of oleanolic acid have been defined; however, to date, no study has been carried out on the effect of CDDOs on human telomerase reverse transcriptase (hTERT) gene or telomerase activity. Here we report for the first time that inhibition of cell proliferation and induction of apoptosis by CDDO-Me in pancreatic cancer cell lines is associated with the inhibition of hTERT gene expression, hTERT telomerase activity and a number of proteins that regulate hTERT expression and activity. Furthermore, abrogation or overexpression of hTERT protein altered the susceptibility of tumor cells to CDDO-Me. These findings suggest that telomerase (hTERT) is a relevant target of CDDO-Me in pancreatic cancer cells.

  14. Genetic evidence that intratumoral T-cell proliferation and activation is associated with recurrence and survival in patients with resected colorectal liver metastases

    OpenAIRE

    Maker, Ajay V; Ito, Hiromichi; Mo, Qianxing; Weisenberg, Elliot; Qin, Li-Xuan; Turcotte, Simon; Maithel, Shishir; Shia, Jinru; Blumgart, Leslie; Fong, Yuman; Jarnagin, William R; DeMatteo, Ronald P.; D'Angelica, Michael I.

    2015-01-01

    Though immune responses correlate with prognosis in primary colorectal cancer, the role of tumor immunity in metastatic disease is less clear. We hypothesized that patient survival and tumor recurrence correlate with transcriptional evidence of lymphocyte proliferation/activation in resected colorectal cancer liver metastases (CRLM). Microarray gene analysis was performed on liver tumor specimens from 96 patients who underwent resection for CRLM. A Cox proportional hazards model identified ge...

  15. Proliferating cells in psoriatic dermis are comprised primarily of T cells, endothelial cells, and factor XIIIa+ perivascular dendritic cells

    Energy Technology Data Exchange (ETDEWEB)

    Morganroth, G.S.; Chan, L.S.; Weinstein, G.D.; Voorhees, J.J.; Cooper, K.D. (Univ. of Michigan Medical School, Ann Arbor (USA))

    1991-03-01

    Determination of the cell types proliferating in the dermis of patients with psoriasis should identify those cells experiencing activation or responding to growth factors in the psoriatic dermal milieu. Toward that end, sections of formalin-fixed biopsies obtained from 3H-deoxyuridine (3H-dU)-injected skin of eight psoriatic patients were immunostained, followed by autoradiography. Proliferating dermal cells exhibit silver grains from tritium emissions. The identity of the proliferating cells could then be determined by simultaneous visualization with antibodies specific for various cell types. UCHL1+ (CD45RO+) T cells (recall antigen-reactive helper T-cell subset) constituted 36.6 +/- 3.1% (mean +/- SEM, n = 6) of the proliferating dermal cells in involved skin, whereas Leu 18+ (CD45RA+) T cells (recall antigen naive T-cell subsets) comprised only 8.7 +/- 1.5% (n = 6). The Factor XIIIa+ dermal perivascular dendritic cell subset (24.9 +/- 1.5% of proliferating dermal cells, n = 6) and Factor VIII+ endothelial cells represented the two other major proliferating populations in lesional psoriatic dermis. Differentiated tissue macrophages, identified by phase microscopy as melanophages or by immunostaining with antibodies to Leu M1 (CD15) or myeloid histiocyte antigen, comprised less than 5% of the proliferating population in either skin type. In addition to calculating the relative proportions of these cells to each other as percent, we also determined the density of cells, in cells/mm2 of tissue. The density of proliferating cells within these populations was increased in involved versus uninvolved skin: UCHL1+, 9.0 +/- 1.7 cells/mm2 versus 1.8 +/- 0.6 cells/mm2, p less than 0.01; Factor XIIIa+, 6.0 +/- 0.7 cells/mm2 versus 1.5 +/- 0.5 cells/mm2, p less than 0.01; Factor VIII+, 5.5 +/- 1.4 cells/mm2 versus 0.0 cells/mm2, p less than 0.05.

  16. Daucosterol promotes the proliferation of neural stem cells.

    Science.gov (United States)

    Jiang, Li-hua; Yang, Nian-yun; Yuan, Xiao-lin; Zou, Yi-jie; Zhao, Feng-ming; Chen, Jian-ping; Wang, Ming-yan; Lu, Da-xiang

    2014-03-01

    Neural stem cells (NSCs) are self-regenerating cells, but their regenerative capacity is limited. The present study was conducted to investigate the effect of daucosterol (a sterolin) on the promotion of NSC proliferation and determine the corresponding molecular mechanism. Results of cell counting kit-8 (CCK-8) assay showed that daucosterol significantly increased the quantity of viable cells and the effectiveness of daucosterol was similar to that of basic fibroblast growth factor (bFGF) and epidermal growth factor (EGF). Flow cytometry detection of CFSE-labeled (CFSE, carboxyfluorescein diacetate succinimidyl ester) NSCs showed that Div Index (or the average number of cell divisions) and % Divided (or the percentage of cells that divided at least once) of the cells were increased, indicating that daucosterol increased the percentage of NSCs re-entering the cell cycle. mRNA microarray analysis showed that 333 genes that are mostly involved in the mitotic cell cycle were up-regulated. By contrast, 627 genes that are mostly involved in differentiation were down-regulated. In particular, insulin-like growth factor I (IGF1) was considered as an important regulatory gene that functionally promoted NSC proliferation, and the increased expression of IGF1 protein was validated by ELISA. In addition, the phosphorylation of AKT was increased, indicating that the proliferation-enhancing activity of daucosterol may be involved in IGF1-AKT pathway. Our study provided information about daucosterol as an efficient and inexpensive growth factor alternative that could be used in clinical medicine and research applications. PMID:24333794

  17. Controling stem cell proliferation - CKIs at work

    NARCIS (Netherlands)

    Bruggeman, SWM; van Lohuizen, M

    2006-01-01

    The cyclin-dependent kinase inhibitors or CKIs are well recognized as intrinsic regulators of the cell cycle. Here, we discuss recent data implicating their activity in restraining adult stem cell self-renewal, and the role that proteins regulating CKI expression play in this process.

  18. Cancer specificity of promoters of the genes controlling cell proliferation.

    Science.gov (United States)

    Kashkin, Kirill; Chernov, Igor; Stukacheva, Elena; Monastyrskaya, Galina; Uspenskaya, Natalya; Kopantzev, Eugene; Sverdlov, Eugene

    2015-02-01

    Violation of proliferation control is a common feature of cancer cells. We put forward the hypothesis that promoters of genes involved in the control of cell proliferation should possess intrinsic cancer specific activity. We cloned promoter regions of CDC6, POLD1, CKS1B, MCM2, and PLK1 genes into pGL3 reporter vector and studied their ability to drive heterologous gene expression in transfected cancer cells of different origin and in normal human fibroblasts. Each promoter was cloned in short (335-800 bp) and long (up to 2.3 kb) variants to cover probable location of core and whole promoter regulatory elements. Cloned promoters were significantly more active in cancer cells than in normal fibroblasts that may indicate their cancer specificity. Both versions of CDC6 promoters were shown to be most active while the activities of others were close to that of BIRC5 gene (survivin) gene promoter. Long and short variants of each cloned promoter demonstrated very similar cancer specificity with the exception of PLK1-long promoter that was substantially more specific than its short variant and other promoters under study. The data indicate that most of the important cis-regulatory transcription elements responsible for intrinsic cancer specificity are located in short variants of the promoters under study. CDC6 short promoter may serve as a promising candidate for transcription targeted cancer gene therapy.

  19. SerpinB1 Promotes Pancreatic β Cell Proliferation

    Energy Technology Data Exchange (ETDEWEB)

    Quaamari, Abdelfattah; Dirice, Ercument; Gedeon, Nicholas; Hu, Jiang; Zhou, Jian-Ying; Shirakawa, Jun; Hou, Lifei; Goodman, Jessica; Karampelias, Christos; Qiang, Guifeng; Boucher, Jeremie; Martinez, Rachael; Gritsenko, Marina A.; De Jesus, Dario F.; Kahraman, Sevim; Bhatt, Shweta; Smith, Richard D.; Beer, Hans-Dietmar; Jungtrakoon, Prapaporn; Gong, Yanping; Goldfine, Allison B.; Liew, Chong Wee; Doria, Alessandro; Andersson, Olov; Qian, Weijun; Remold-O' Donnell, Eileen; Kulkami, Rohit N.

    2016-01-12

    Compensatory β-cell growth in response to insulin resistance is a common feature in diabetes. We recently reported that liver-derived factors participate in this compensatory response in the liver insulin receptor knockout (LIRKO) mouse, a model of significant islet hyperplasia. Here we show that serpinB1 is a liver-derived secretory protein that controls β-cell proliferation. SerpinB1 is abundant in the hepatocyte secretome and sera derived from LIRKO mice. SerpinB1 and small molecule compounds that partially mimic serpinB1 activity enhanced proliferation of zebrafish, mouse and human β-cells. We report that serpinB1-induced β-cell replication requires protease inhibition activity and mice lacking serpinB1 exhibit attenuated β-cell replication in response to insulin resistance. Finally, SerpinB1-treatment of islets modulated signaling proteins in growth and survival pathways such as MAPK, PKA and GSK3. Together, these data implicate SerpinB1 as a protein that can potentially be harnessed to enhance functional β-cell mass in patients with diabetes.

  20. Wnt inhibitory factor-1 regulates glioblastoma cell cycle and proliferation.

    Science.gov (United States)

    Wu, Jun; Fang, Jiasheng; Yang, Zhuanyi; Chen, Fenghua; Liu, Jingfang; Wang, Yanjin

    2012-10-01

    Wnt proteins are powerful regulators of cell proliferation and differentiation, and activation of the Wnt signalling pathway is involved in the pathogenesis of several types of human tumours. Wnt inhibitory factor-1 (WIF-1) acts as a Wnt antagonist and tumour suppressor. Previous studies have shown that reducing expression of the WIF-1 gene aberrantly activates Wnt signalling and induces the development of certain types of cancers. In the present study, we examined the expression of WIF-1 in human primary glioblastoma multiforme (GBM) tumours. Studies using semiquantitative reverse transcription-polymerase chain reaction and immunohistochemical analysis revealed that WIF-1 expression is lower in human GBM than in normal brain tissue. To clarify the role of WIF-1, we transfected U251 human glioblastoma-derived cells, which do not express WIF-1, with the pcDNA3.1-WIF1 vector to restore WIF-1 expression. The results of cell proliferation, colony formation and apoptosis assays, as well as flow cytometry, indicate that exogenous WIF-1 has no effect on U251 cell apoptosis, but does arrest cells at the G(0)/G(1) phase and inhibit cell growth. Collectively, our data suggest that WIF-1 is a potent inhibitor of GBM growth. PMID:22901505

  1. Hypoxia-inducible factor-1α increased the expression of peroxisome proliferator activated receptor α in lung cancer cell A549

    Institute of Scientific and Technical Information of China (English)

    张惠兰; 张珍祥; 徐永健

    2004-01-01

    @@ Hypoxia plays a fundamental role in many pathologic processes. Hypoxia-inducible factor-1 (HIF-1) is a heterodimeric basic helix-loop-helix-per-aryl hydrocarbon receptor ARNT-sim (PAS) domain protein, consisting of α and β subunits and is precisely regulated by cellular oxygen levels.1 The peroxisome proliferator-activated receptors (PPARs) are family nuclear hormone-binding proteins with increasing diverse functions as transcriptional regulators, owning three subtypes (α, β, and γ).2 PPARα plays a critical physiological role as lipid sensors and regulators of proliferation.3 Hypoxia can elicit up-regulation of PPAR-α expression.4 Herein, we report the results of an investigation on the correlation of HIF-1α and PPARα.

  2. Interleukin-2 carbohydrate recognition modulates CTLL-2 cell proliferation.

    Science.gov (United States)

    Fukushima, K; Yamashita, K

    2001-03-01

    Interleukin-2 (IL-2) specifically recognizes high-mannose type glycans with five or six mannosyl residues. To determine whether the carbohydrate recognition activity of IL-2 contributes to its physiological activity, the inhibitory effects of high-mannose type glycans on IL-2-dependent CTLL-2 cell proliferation were investigated. Man(5)GlcNAc(2)Asn added to CTLL-2 cell cultures inhibited not only phosphorylation of tyrosine kinases but also IL-2-dependent cell proliferation. We found that a complex of IL-2, IL-2 receptor alpha, beta, gamma subunits, and tyrosine kinases was formed in rhIL-2-stimulated CTLL-2 cells. Among the components of this complex, only the IL-2 receptor alpha subunit was stained with Galanthus nivalis agglutinin which specifically recognizes high-mannose type glycans. This staining was diminished after digestion of the glycans with endo-beta-N-acetylglucosaminidase H or D, suggesting that at least a N-glycan containing Man(5)GlcNAc(2) is linked to the extracellular portion of the IL-2 receptor alpha subunit. Our findings indicate that IL-2 binds the IL-2 receptor alpha subunit through Man(5)GlcNAc(2) and a specific peptide sequence on the surface of CTLL-2 cells. When IL-2 binds to the IL-2Ralpha subunit, this may trigger formation of the high affinity complex of IL-2-IL-2Ralpha, -beta, and -gamma subunits, leading to cellular signaling.

  3. Beta cell proliferation and growth factors

    DEFF Research Database (Denmark)

    Nielsen, Jens Høiriis; Svensson, C; Møldrup, Annette;

    1999-01-01

    Formation of new beta cells can take place by two pathways: replication of already differentiated beta cells or neogenesis from putative islet stem cells. Under physiological conditions both processes are most pronounced during the fetal and neonatal development of the pancreas. In adulthood little...... cloned a novel GH/PRL stimulated rat islet gene product, Pref-1 (preadipocyte factor-1). This protein contains six EGF-like motifs and may play a role both in embryonic pancreas differentiation and in beta cell growth and function. In summary, the increasing knowledge about the mechanisms involved...... increase in the beta cell number seems to occur. In pregnancy, however, a marked hyperplasia of the beta cells is observed both in rodents and man. Increased mitotic activity has been seen both in vivo and in vitro in islets exposed to placental lactogen (PL), prolactin (PRL) and growth hormone (GH...

  4. Peroxisome proliferator-activated receptors for hypertension

    Institute of Scientific and Technical Information of China (English)

    Daisuke; Usuda; Tsugiyasu; Kanda

    2014-01-01

    Peroxisome proliferator-activated receptors(PPARs) are ligand-activated transcription factors belonging to the nuclear receptor superfamily, which is composed of four members encoded by distinct genes(α, β, γ, and δ). The genes undergo transactivation or transrepression under specific mechanisms that lead to the induction or repression of target gene expression. As is the case with other nuclear receptors, all four PPAR isoforms contain five or six structural regions in four functional domains; namely, A/B, C, D, and E/F. PPARs have many functions, particularly functions involving control of vascular tone, inflammation, and energy homeostasis, and are, therefore, important targets for hypertension, obesity, obesity-induced inflammation, and metabolic syndrome in general. Hence, PPARs also represent drug targets, and PPARα and PPARγ agonists are used clinically in the treatment of dyslipidemia and type 2 diabetes mellitus, respectively. Because of their pleiotropic effects, they have been identified as active in a number of diseases and are targets for the development of a broad range of therapies for a variety of diseases. It is likely that the range of PPARγ agonist therapeutic actions will result in novel approaches to lifestyle and other diseases. The combination of PPARs with reagents or with other cardiovascular drugs, such as diuretics and angiotensin Ⅱ receptor blockers, should be studied.This article provides a review of PPAR isoform characteristics, a discussion of progress in our understanding of the biological actions of PPARs, and a summary of PPAR agonist development for patient management. We also include a summary of the experimental and clinical evidence obtained from animal studies and clinical trials conducted to evaluate the usefulness and effectiveness of PPAR agonists in the treatment of lifestyle-related diseases.

  5. EEN regulates the proliferation and survival of multiple myeloma cells by potentiating IGF-1 secretion

    International Nuclear Information System (INIS)

    Highlights: • Levels of EEN expression paralleled with the rate of cell proliferation. • EEN was involved in the proliferation and survival of multiple myeloma (MM) cells. • EEN regulated the activity of IGF-1-Akt/mTOR pathway. • EEN regulated proliferation and survival of MM cells by enhancing IGF-1 secretion. - Abstract: The molecular mechanisms of multiple myeloma are not well defined. EEN is an endocytosis-regulating molecule. Here we report that EEN regulates the proliferation and survival of multiple myeloma cells, by regulating IGF-1 secretion. In the present study, we observed that EEN expression paralleled with cell proliferation, EEN accelerated cell proliferation, facilitated cell cycle transition from G1 to S phase by regulating cyclin-dependent kinases (CDKs) pathway, and delayed cell apoptosis via Bcl2/Bax-mitochondrial pathway. Mechanistically, we found that EEN was indispensable for insulin-like growth factor-1 (IGF-1) secretion and the activation of protein kinase B-mammalian target of rapamycin (Akt-mTOR) pathway. Exogenous IGF-1 overcame the phenotype of EEN depletion, while IGF-1 neutralization overcame that of EEN over-expression. Collectively, these data suggest that EEN may play a pivotal role in excessive cell proliferation and insufficient cell apoptosis of bone marrow plasma cells in multiple myeloma. Therefore, EEN may represent a potential diagnostic marker or therapeutic target for multiple myeloma

  6. EEN regulates the proliferation and survival of multiple myeloma cells by potentiating IGF-1 secretion

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Er-Wen [Guangzhou Institute of Forensic Science, Guangzhou (China); Department of Forensic Pathology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou (China); Xue, Sheng-Jiang [Department of Forensic Pathology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou (China); Li, Xiao-Yan [Department of Pharmacy, The Third Affiliated Hospital, Sun Yat-Sen University, Guangzhou (China); Xu, Suo-Wen [Department of Pharmacology and Toxicology, School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou (China); Cheng, Jian-Ding; Zheng, Jin-Xiang [Department of Forensic Pathology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou (China); Shi, He; Lv, Guo-Li; Li, Zhi-Gang; Li, Yue; Liu, Chang-Hui; Chen, Xiao-Hui; Liu, Hong [Guangzhou Institute of Forensic Science, Guangzhou (China); Li, Jie, E-mail: mdlijie@sina.com [Department of Anaesthesiology, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou (China); Liu, Chao, E-mail: liuchaogaj@21cn.com [Guangzhou Institute of Forensic Science, Guangzhou (China)

    2014-05-02

    Highlights: • Levels of EEN expression paralleled with the rate of cell proliferation. • EEN was involved in the proliferation and survival of multiple myeloma (MM) cells. • EEN regulated the activity of IGF-1-Akt/mTOR pathway. • EEN regulated proliferation and survival of MM cells by enhancing IGF-1 secretion. - Abstract: The molecular mechanisms of multiple myeloma are not well defined. EEN is an endocytosis-regulating molecule. Here we report that EEN regulates the proliferation and survival of multiple myeloma cells, by regulating IGF-1 secretion. In the present study, we observed that EEN expression paralleled with cell proliferation, EEN accelerated cell proliferation, facilitated cell cycle transition from G1 to S phase by regulating cyclin-dependent kinases (CDKs) pathway, and delayed cell apoptosis via Bcl2/Bax-mitochondrial pathway. Mechanistically, we found that EEN was indispensable for insulin-like growth factor-1 (IGF-1) secretion and the activation of protein kinase B-mammalian target of rapamycin (Akt-mTOR) pathway. Exogenous IGF-1 overcame the phenotype of EEN depletion, while IGF-1 neutralization overcame that of EEN over-expression. Collectively, these data suggest that EEN may play a pivotal role in excessive cell proliferation and insufficient cell apoptosis of bone marrow plasma cells in multiple myeloma. Therefore, EEN may represent a potential diagnostic marker or therapeutic target for multiple myeloma.

  7. An extra high dose of erythropoietin fails to support the proliferation of erythropoietin dependent cell lines

    OpenAIRE

    ABE, Satoshi; Sasaki, Ryuzo; Masuda, Seiji

    2011-01-01

    Erythropoietin is responsible for the red blood cell formation by stimulating the proliferation and the differentiation of erythroid precursor cells. Erythropoietin triggers the conformational change in its receptor thereby induces the phosphorylation of JAK2. In this study, we show that an extra high dose of erythropoietin, however, fails to activate the erythropoietin receptor, to stimulate the phosphorylation of JAK2 and to support the cell proliferation of Ep-FDC-P2 cell. Moreover, high d...

  8. Matrix metalloproteinase-3 in odontoblastic cells derived from ips cells: unique proliferation response as odontoblastic cells derived from ES cells.

    Directory of Open Access Journals (Sweden)

    Taiki Hiyama

    Full Text Available We previously reported that matrix metalloproteinase (MMP-3 accelerates wound healing following dental pulp injury. In addition, we reported that a proinflammatory cytokine mixture (tumor necrosis factor-α, interleukin (IL-1β and interferon-γ induced MMP-3 activity in odontoblast-like cells derived from mouse embryonic stem (ES cells, suggesting that MMP-3 plays a potential unique physiological role in wound healing and regeneration of dental pulp in odontoblast-like cells. In this study, we tested the hypothesis that upregulation of MMP-3 activity by IL-1β promotes proliferation and apoptosis of purified odontoblast-like cells derived from induced pluripotent stem (iPS and ES cells. Each odontoblast-like cell was isolated and incubated with different concentrations of IL-1β. MMP-3 mRNA and protein expression were assessed using RT-PCR and western blotting, respectively. MMP-3 activity was measured using immunoprecipitation and a fluorescence substrate. Cell proliferation and apoptosis were determined using ELISA for BrdU and DNA fragmentation, respectively. siRNA was used to reduce MMP-3 transcripts in these cells. Treatment with IL-1β increased MMP-3 mRNA and protein levels, and MMP-3 activity in odontoblast-like cells. Cell proliferation was found to markedly increase with no changes in apoptosis. Endogenous tissue inhibitor of metalloproteinase (TIMP-1 and TIMP-2 were constitutively expressed during all experiments. The exocytosis inhibitor, Exo1, potently suppressed the appearance of MMP-3 in the conditioned medium. Treatment with siRNA against MMP-3 suppressed an IL-1β-induced increase in MMP-3 expression and activity, and also suppressed cell proliferation, but unexpectedly increased apoptosis in these cells (P<0.05. Exogenous MMP-3 was found to induce cell proliferation in odontoblast-like cells derived from iPS cells and ES cells. This siRNA-mediated increase in apoptosis could be reversed with exogenous MMP-3 stimulation (P<0

  9. miR-965 controls cell proliferation and migration during tissue morphogenesis in the Drosophila abdomen

    DEFF Research Database (Denmark)

    Verma, Pushpa; Cohen, Stephen M

    2015-01-01

    , they remain quiescent during larval development. During pupal development, the abdominal histoblast cells proliferate and migrate to replace the larval epidermis. Here, we provide evidence that the microRNA, miR-965, acts via string and wingless to control histoblast proliferation and migration. Ecdysone...... signaling downregulates miR-965 at the onset of pupariation, linking activation of the histoblast nests to the hormonal control of metamorphosis. Replacement of the larval epidermis by adult epidermal progenitors involves regulation of both cell-intrinsic events and cell communication. By regulating both...... cell proliferation and cell migration, miR-965 contributes to the robustness of this morphogenetic system....

  10. Cell proliferation in the presence of telomerase.

    Directory of Open Access Journals (Sweden)

    Krastan B Blagoev

    Full Text Available BACKGROUND: Telomerase, which is active early in development and later in stem and germline cells, is also active in the majority of human cancers. One of the known functions of telomerase is to extend the ends of linear chromosomes, countering their gradual shortening at each cell division due to the end replication problem and postreplication processing. Telomerase concentration levels vary between different cell types as well as between different tumors. In addition variable telomerase concentrations will exist in different cells in the same tumor when telomerase inhibitors are used, because of limitations of drug delivery in tissue. Telomerase extends short telomeres more frequently than long telomeres and the relation between the extension frequency and the telomere length is nonlinear. METHODOLOGY/PRINCIPAL FINDINGS: Here, the biological data of the nonlinear telomerase-telomere dynamics is incorporated in a mathematical theory to relate the proliferative potential of a cell to the telomerase concentration in that cell. The main result of the paper is that the proliferative capacity of a cell grows exponentially with the telomerase concentration. CONCLUSIONS/SIGNIFICANCE: The theory presented here suggests that long term telomerase inhibition in every cancer progenitor or cancer stem cell is needed for successful telomere targeted cancer treatment. This theory also can be used to plan and assess the results of clinical trials targeting telomerase.

  11. Adenovirus-mediated Transfer of p53 and p16 Inhibiting Proliferating Activity of Human Bladder Cancer Cell EJ in vitro and in vivo

    Institute of Scientific and Technical Information of China (English)

    朱朝辉; 邢诗安; 林晨; 曾甫清; 鲁功成; 付明; 张雪艳; 梁萧; 吴旻

    2002-01-01

    Summary: To evaluate the effects of adenovirus (Ad)-mediated transfer of p53 and p16 on humanbladder cancer cells EJ, EJ were transfected with Ad-p53 and Ad-p16. Cell growth, morphologi-cal change, cell cycle, apoptosis were measured using MTT assay, flow gytometry, cloning forma-tion, immunocytochemical assays. Ad-p16 or Ad-p53 alone could inhibit the proliferating activityof EJ cells in vitro. Ad-p53 could induce apoptosis of partial EJ cells. G1 arrest was observed 72 hafter infection with Ad-p16, but apoptosis was not obvious. The transfer of Ad-p16 and Ad-p53could significantly inhibit the growth of EJ cells, decrease the cloning formation rate and induceapoptosis of large number of EJ cells. The occurrence time of subcutaneous tumor was delayed andthe tumor volume in 4 weeks was diminished by using Ad-p53 combined with Ad-p16 and the dif-ference was significant compared with using Ad-p53 or Ad-p16 alone. It was suggested that thetransfer of wild-type p53 and p16 could significantly inhibit the growth of human bladder cancer invitro and in vivo.

  12. Vasoactive intestinal peptide (VIP) inhibits human renal cell carcinoma proliferation.

    Science.gov (United States)

    Vacas, Eva; Fernández-Martínez, Ana B; Bajo, Ana M; Sánchez-Chapado, Manuel; Schally, Andrew V; Prieto, Juan C; Carmena, María J

    2012-10-01

    Clear renal cell carcinoma (cRCC) is an aggressive and fatal neoplasm. The present work was undertaken to investigate the antiproliferative potential of vasoactive intestinal peptide (VIP) exposure on non-tumoral (HK2) and tumoral (A498, cRCC) human proximal tubular epithelial cell lines. Reverse transcription and semiquantitative PCR was used at the VIP mRNA level whereas enzyme immunoanalysis was performed at the protein level. Both renal cell lines expressed VIP as well as VIP/pituitary adenylate cyclase-activating peptide (VPAC) receptors whereas only HK2 cells expressed formyl peptide receptor-like 1 (FPRL-1). Receptors were functional, as shown by VIP stimulation of adenylyl cyclase activity. Treatment with 0.1μM VIP (24h) inhibited proliferation of A498 but not HK2 cells as based on a reduction in the incorporation of [(3)H]-thymidine and BrdU (5'-Br-2'-deoxyuridine), PCNA (proliferating-cell nuclear antigen) expression and STAT3 (signal transducer and activator of transcription 3) expression and activation. VPAC(1)-receptor participation was established using JV-1-53 antagonist and siRNA transfection. Growth-inhibitory response to VIP was related to the cyclic adenosine monophosphate (cAMP)/exchange protein directly activated by cAMP (EPAC)/phosphoinositide 3-kinase (PI3-K) signaling systems as shown by studies on adenylate cyclase stimulation, and using the EPAC-specific compound 8CPT-2Me-cAMP and specific kinase inhibitors such as H89, wortmannin and PD98059. The efficacy of VIP on the prevention of tumor progression was confirmed in vivo using xenografted athymic mouse. These actions support a potential role of this peptide and its agonists in new therapies for cRCC.

  13. Stimulation of neoplastic mouse lung cell proliferation by alveolar macrophage-derived, insulin-like growth factor-1 can be blocked by inhibiting MEK and PI3K activation

    Directory of Open Access Journals (Sweden)

    Malkinson Alvin M

    2011-06-01

    Full Text Available Abstract Background Worldwide, lung cancer kills more people than breast, colon and prostate cancer combined. Alterations in macrophage number and function during lung tumorigenesis suggest that these immune effector cells stimulate lung cancer growth. Evidence from cancer models in other tissues suggests that cancer cells actively recruit growth factor-producing macrophages through a reciprocal signaling pathway. While the levels of lung macrophages increase during tumor progression in mouse models of lung cancer, and high pulmonary macrophage content correlates with a poor prognosis in human non-small cell lung cancer, the specific role of alveolar macrophages in lung tumorigenesis is not clear. Methods After culturing either an immortalized lung macrophage cell line or primary murine alveolar macrophages from naïve and lung-tumor bearing mice with primary tumor isolates and immortalized cell lines, the effects on epithelial proliferation and cellular kinase activation were determined. Insulin-like growth factor-1 (IGF-1 was quantified by ELISA, and macrophage conditioned media IGF-1 levels manipulated by IL-4 treatment, immuno-depletion and siRNA transfection. Results Primary macrophages from both naïve and lung-tumor bearing mice stimulated epithelial cell proliferation. The lungs of tumor-bearing mice contained 3.5-times more IGF-1 than naïve littermates, and media conditioned by freshly isolated tumor-educated macrophages contained more IGF-1 than media conditioned by naïve macrophages; IL-4 stimulated IGF-1 production by both macrophage subsets. The ability of macrophage conditioned media to stimulate neoplastic proliferation correlated with media IGF-1 levels, and recombinant IGF-1 alone was sufficient to induce epithelial proliferation in all cell lines evaluated. Macrophage-conditioned media and IGF-1 stimulated lung tumor cell growth in an additive manner, while EGF had no effect. Macrophage-derived factors increased p-Erk1/2, p

  14. ETOH inhibits embryonic neural stem/precursor cell proliferation via PLD signaling

    International Nuclear Information System (INIS)

    While a mother's excessive alcohol consumption during pregnancy is known to have adverse effects on fetal neural development, little is known about the underlying mechanism of these effects. In order to investigate these mechanisms, we investigated the toxic effect of ethanol (ETOH) on neural stem/precursor cell (NSC) proliferation. In cultures of NSCs, phospholipase D (PLD) is activated following stimulation with epidermal growth factor (EGF) and fibroblast growth factor 2 (FGF2). Exposure of NSCs to ETOH suppresses cell proliferation, while it has no effect on cell death. Phosphatidic acid (PA), which is a signaling messenger produced by PLD, reverses ETOH inhibition of NSC proliferation. Blocking the PLD signal by 1-butanol suppresses the proliferation. ETOH-induced suppression of NSC proliferation and the protective effect of PA for ETOH-induced suppression are mediated through extracellular signal-regulated kinase signaling. These results indicate that exposure to ETOH impairs NSC proliferation by altering the PLD signaling pathway

  15. Inhibition of fatty acid metabolism reduces human myeloma cells proliferation.

    Directory of Open Access Journals (Sweden)

    José Manuel Tirado-Vélez

    Full Text Available Multiple myeloma is a haematological malignancy characterized by the clonal proliferation of plasma cells. It has been proposed that targeting cancer cell metabolism would provide a new selective anticancer therapeutic strategy. In this work, we tested the hypothesis that inhibition of β-oxidation and de novo fatty acid synthesis would reduce cell proliferation in human myeloma cells. We evaluated the effect of etomoxir and orlistat on fatty acid metabolism, glucose metabolism, cell cycle distribution, proliferation, cell death and expression of G1/S phase regulatory proteins in myeloma cells. Etomoxir and orlistat inhibited β-oxidation and de novo fatty acid synthesis respectively in myeloma cells, without altering significantly glucose metabolism. These effects were associated with reduced cell viability and cell cycle arrest in G0/G1. Specifically, etomoxir and orlistat reduced by 40-70% myeloma cells proliferation. The combination of etomoxir and orlistat resulted in an additive inhibitory effect on cell proliferation. Orlistat induced apoptosis and sensitized RPMI-8226 cells to apoptosis induction by bortezomib, whereas apoptosis was not altered by etomoxir. Finally, the inhibitory effect of both drugs on cell proliferation was associated with reduced p21 protein levels and phosphorylation levels of retinoblastoma protein. In conclusion, inhibition of fatty acid metabolism represents a potential therapeutic approach to treat human multiple myeloma.

  16. Stimulation of TM3 Leydig cell proliferation via GABAA receptors: A new role for testicular GABA

    Science.gov (United States)

    Geigerseder, Christof; Doepner, Richard FG; Thalhammer, Andrea; Krieger, Annette; Mayerhofer, Artur

    2004-01-01

    The neurotransmitter gamma-aminobutyric acid (GABA) and subtypes of GABA receptors were recently identified in adult testes. Since adult Leydig cells possess both the GABA biosynthetic enzyme glutamate decarboxylase (GAD), as well as GABAA and GABAB receptors, it is possible that GABA may act as auto-/paracrine molecule to regulate Leydig cell function. The present study was aimed to examine effects of GABA, which may include trophic action. This assumption is based on reports pinpointing GABA as regulator of proliferation and differentiation of developing neurons via GABAA receptors. Assuming such a role for the developing testis, we studied whether GABA synthesis and GABA receptors are already present in the postnatal testis, where fetal Leydig cells and, to a much greater extend, cells of the adult Leydig cell lineage proliferate. Immunohistochemistry, RT-PCR, Western blotting and a radioactive enzymatic GAD assay evidenced that fetal Leydig cells of five-six days old rats possess active GAD protein, and that both fetal Leydig cells and cells of the adult Leydig cell lineage possess GABAA receptor subunits. TM3 cells, a proliferating mouse Leydig cell line, which we showed to possess GABAA receptor subunits by RT-PCR, served to study effects of GABA on proliferation. Using a colorimetric proliferation assay and Western Blotting for proliferating cell nuclear antigen (PCNA) we demonstrated that GABA or the GABAA agonist isoguvacine significantly increased TM3 cell number and PCNA content in TM3 cells. These effects were blocked by the GABAA antagonist bicuculline, implying a role for GABAA receptors. In conclusion, GABA increases proliferation of TM3 Leydig cells via GABAA receptor activation and proliferating Leydig cells in the postnatal rodent testis bear a GABAergic system. Thus testicular GABA may play an as yet unrecognized role in the development of Leydig cells during the differentiation of the testicular interstitial compartment. PMID:15040802

  17. Stimulation of TM3 Leydig cell proliferation via GABAA receptors: A new role for testicular GABA

    Directory of Open Access Journals (Sweden)

    Krieger Annette

    2004-03-01

    Full Text Available Abstract The neurotransmitter gamma-aminobutyric acid (GABA and subtypes of GABA receptors were recently identified in adult testes. Since adult Leydig cells possess both the GABA biosynthetic enzyme glutamate decarboxylase (GAD, as well as GABAA and GABAB receptors, it is possible that GABA may act as auto-/paracrine molecule to regulate Leydig cell function. The present study was aimed to examine effects of GABA, which may include trophic action. This assumption is based on reports pinpointing GABA as regulator of proliferation and differentiation of developing neurons via GABAA receptors. Assuming such a role for the developing testis, we studied whether GABA synthesis and GABA receptors are already present in the postnatal testis, where fetal Leydig cells and, to a much greater extend, cells of the adult Leydig cell lineage proliferate. Immunohistochemistry, RT-PCR, Western blotting and a radioactive enzymatic GAD assay evidenced that fetal Leydig cells of five-six days old rats possess active GAD protein, and that both fetal Leydig cells and cells of the adult Leydig cell lineage possess GABAA receptor subunits. TM3 cells, a proliferating mouse Leydig cell line, which we showed to possess GABAA receptor subunits by RT-PCR, served to study effects of GABA on proliferation. Using a colorimetric proliferation assay and Western Blotting for proliferating cell nuclear antigen (PCNA we demonstrated that GABA or the GABAA agonist isoguvacine significantly increased TM3 cell number and PCNA content in TM3 cells. These effects were blocked by the GABAA antagonist bicuculline, implying a role for GABAA receptors. In conclusion, GABA increases proliferation of TM3 Leydig cells via GABAA receptor activation and proliferating Leydig cells in the postnatal rodent testis bear a GABAergic system. Thus testicular GABA may play an as yet unrecognized role in the development of Leydig cells during the differentiation of the testicular interstitial compartment.

  18. Cell death and cell proliferation in mouse submandibular gland during early post-irradiation phase.

    Directory of Open Access Journals (Sweden)

    Bralic,Marina

    2005-08-01

    Full Text Available

    The effects of irradiation on different cell compartments in the submandibular gland were analyzed in adult C57BL/6 mice exposed to X-ray irradiation and followed up for 10 days. Apoptosis was quantified using the terminal deoxynucleotidyl transferase (TdT-mediated dUTP-digoxigenin nick end labeling method (TUNEL. Cell proliferation was detected using immunohistochemistry for proliferating cell nuclear antigen (PCNA. Radiation-induced apoptosis occurred rapidly, reaching a maximum 3 days post-irradiation. The percentage of apoptotic cells increased with the irradiation dose. At day 1 post-irradiation, cell proliferation was significantly reduced in comparison to sham-irradiated controls. After post-irradiation arrest of the cell cycle, proliferation increased in all gland compartments, reaching a maximum at day 6 post-irradiation. The proliferation response corresponded to the dose of irradiation. We suggest that the reason for gland dysfunction could be the coexistence of high apoptotic and proliferative activity in the irradiated gland.

  19. The Relationship of Expression of bcl-2, p53, and Proliferating Cell Nuclear Antigen (PCNA) to Cell Proliferation and Apoptosis in Renal Cell Carcinoma

    Institute of Scientific and Technical Information of China (English)

    朱朝辉; 邢诗安; 程平; 李国胜; 杨郁; 曾甫清; 鲁功成

    2004-01-01

    To investigate the relationship of bcl-2, p53, proliferating cell nuclear antigen (PCNA) to cell proliferation, apoptosis and pathological parameters, the patterns of cell growth and turnover in renal cell carcinoma (RCC), formalin-fixed and paraffin-embedded tissue blocks from 34 patients with RCC were examined. Cell proliferation activity was detected by PCNA immunostaining and the proliferation index (PI) was expressed as a percentage of the PCNA-positive cells in the tumor cells. Apoptosis was detected by terminal deoxy- nucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL), and the apoptotic index (AI) was expressed as a percentage of the TUNEL-positive cells in the tumor cells. Expressions of bcl-2 and p53 were assessed immunohistochemically. Our results showed that the PI ranged from 6.0 % to 24.0 % (median 12.3 %) and theAI from 2.0 % to 8.0 % (median 5.4 %) in RCC. The expression of the bcl-2 protein was demonstrated in 15 cases (44.1 %); the expression of the p53 protein, however, was seen in only 3 case. bcl-2 positivity was not associated with PI or AI or any pathological parameters. There were close associations between PI and tumor grade and stage, and a significant relationship between AI and the tumor grade of RCC. Our study suggests that bcl-2 positivity was not associated with PI or AI or any pathological parameters. There are close associations between PI and AI and tumor grade and stage of RCC. Active cell proliferation may be accompanied by frequent apoptosis in RCC.

  20. The role of glutathione in lymphocyte activation and proliferation

    International Nuclear Information System (INIS)

    The object of this work was to establish the requirement for GSH and cystine during the activation and proliferation of human peripheral blood mononuclear cells (PBMC). In the author's initial experiments the intracellular GSH content of PBMC was altered by continuous culture or pretreatment with BSO, a specific inhibitor of GSH synthesis. His results demonstrate that, continuous culture of mitogen stimulated PBMC in the presence of BSO inhibited entry into S-phase of the cell cycle and produced a simultaneous decrease in intracellular GSH. The influence of BSO on early activation events were determined by BSO pretreatment. Extensive depletion (>90%) of the intracellular GSH level prior to mitogenic stimulation did not impair the ability of these cells to produce IL-2 and express IL-2R, indicating that GSH may not be involved in the generation and response to early activation signals. Furthermore, the removal of BSO from these cultures rapidly reversed its inhibitory effects on DNA and GSH synthesis. Cystine transport activities and metabolism by PBMC were characterized in order to examine its contributions to intracellular GSH and early activation proteins. In spite of the ability of cystine to sustain the proliferative response of PBMC, differences in the kinetics of cystine and cysteine uptake indicated that separate transport systems may be operational. Treatment with 2ME enhanced cystine uptake, but lowered the proliferative responses of these cells. Metabolic studies with [35S] cystine demonstrated that mitogen stimulation of PBMC enhance cystine uptake

  1. Rac1 drives intestinal stem cell proliferation and regeneration

    OpenAIRE

    Myant, K.B.; Scopelliti, A.; Haque, S; Vidal, M; Sansom, O J; Cordero, J.B.

    2013-01-01

    Adult stem cells are responsible for maintaining the balance between cell proliferation and differentiation within self-renewing tissues. The molecular and cellular mechanisms mediating such balance are poorly understood. The production of reactive oxygen species (ROS) has emerged as an important mediator of stem cell homeostasis in various systems. Our recent work demonstrates that Rac1-dependent ROS production mediates intestinal stem cell (ISC) proliferation in mouse models of colorectal c...

  2. In vitro proliferation of adult human beta-cells.