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Sample records for cell signalling inhibition

  1. Andrographolide inhibits multiple myeloma cells by inhibiting the TLR4/NF-κB signaling pathway.

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    Gao, Hui; Wang, Jianrong

    2016-02-01

    Andrographolide is an active component from the extract of Andrographis paniculata [(Burm.f) Nees], a medicinal plant from the Acanthaceae family. Pharmacological studies have revealed that andrographolide possesses anti-bacterial, anti-inflammatory, anti-viral, immune regulatory and hepatoprotective properties, and is efficacious in the treatment of cardiovascular diseases, while exhibiting low toxicity and low cost. The present study aimed to determine the inhibitory effects of andrographolide on the growth of multiple myeloma (MM) cells and its possible impact on the Toll-like receptor (TLR)4/nuclear factor (NF)-κB signaling pathway. Cell proliferation was detected using an MTT assay, cellular apoptosis was measured using flow cytometry, and caspase-9/3 activation were assessed using colorimetric assay kits. Furthermore, TLR4 and NF-κB protein expression was determined by western blot analysis. The results revealed that andrographolide reduced the proliferation, while increasing cellular apoptosis and caspase-9/3 activation of MM cells, in addition to downregulating the expression of TLR4 and NF-κB protein. Of note, TLR4- or NF-κB-targeting small-interfering (si)RNA enhanced the andrographolide-induced inhibition of cell proliferation and induction of apoptosis of MM cells. The results of the present study therefore suggested that andrographolide inhibited multiple myeloma cells via the TLR4/NF-κB signaling pathway. PMID:26707811

  2. Mouse bone marrow stromal cells differentiate to neuron-like cells upon inhibition of BMP signaling.

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    Saxena, Monika; Prashar, Paritosh; Yadav, Prem Swaroop; Sen, Jonaki

    2016-01-01

    Bone marrow stromal cells (BMSCs) are a source of autologous stem cells that have the potential for undergoing differentiation into multiple cell types including neurons. Although the neuronal differentiation of mesenchymal stem cells has been studied for a long time, the molecular players involved are still not defined. Here we report that the genetic deletion of two members of the bone morphogenetic protein (Bmp) family, Bmp2 and Bmp4 in mouse BMSCs causes their differentiation into cells with neuron-like morphology. Surprisingly these cells expressed certain markers characteristic of both neuronal and glial cells. Based on this observation, we inhibited BMP signaling in mouse BMSCs through a brief exposure to Noggin protein which also led to their differentiation into cells expressing both neuronal and glial markers. Such cells seem to have the potential for further differentiation into subtypes of neuronal and glial cells and thus could be utilized for cell-based therapeutic applications.

  3. Arsenic inhibits hedgehog signaling during P19 cell differentiation

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    Liu, Jui Tung [Environmental Toxicology Program, Clemson University, 132 Long Hall, Clemson, SC 29634 (United States); Bain, Lisa J., E-mail: lbain@clemson.edu [Environmental Toxicology Program, Clemson University, 132 Long Hall, Clemson, SC 29634 (United States); Department of Biological Sciences, Clemson University, 132 Long Hall, Clemson, SC 29634 (United States)

    2014-12-15

    Arsenic is a toxicant found in ground water around the world, and human exposure mainly comes from drinking water or from crops grown in areas containing arsenic in soils or water. Epidemiological studies have shown that arsenic exposure during development decreased intellectual function, reduced birth weight, and altered locomotor activity, while in vitro studies have shown that arsenite decreased muscle and neuronal cell differentiation. The sonic hedgehog (Shh) signaling pathway plays an important role during the differentiation of both neurons and skeletal muscle. The purpose of this study was to investigate whether arsenic can disrupt Shh signaling in P19 mouse embryonic stem cells, leading to changes muscle and neuronal cell differentiation. P19 embryonic stem cells were exposed to 0, 0.25, or 0.5 μM of sodium arsenite for up to 9 days during cell differentiation. We found that arsenite exposure significantly reduced transcript levels of genes in the Shh pathway in both a time and dose-dependent manner. This included the Shh ligand, which was decreased 2- to 3-fold, the Gli2 transcription factor, which was decreased 2- to 3-fold, and its downstream target gene Ascl1, which was decreased 5-fold. GLI2 protein levels and transcriptional activity were also reduced. However, arsenic did not alter GLI2 primary cilium accumulation or nuclear translocation. Moreover, additional extracellular SHH rescued the inhibitory effects of arsenic on cellular differentiation due to an increase in GLI binding activity. Taken together, we conclude that arsenic exposure affected Shh signaling, ultimately decreasing the expression of the Gli2 transcription factor. These results suggest a mechanism by which arsenic disrupts cell differentiation. - Highlights: • Arsenic exposure decreases sonic hedgehog pathway-related gene expression. • Arsenic decreases GLI2 protein levels and transcriptional activity in P19 cells. • Arsenic exposure does not alter the levels of SHH

  4. Simvastatin induces cell cycle arrest and inhibits proliferation of bladder cancer cells via PPARγ signalling pathway

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    Wang, Gang; Cao, Rui; Wang, Yongzhi; Qian, Guofeng; Dan, Han C.; Jiang, Wei; Ju, Lingao; Wu, Min; Xiao, Yu; Wang, Xinghuan

    2016-01-01

    Simvastatin is currently one of the most common drugs for old patients with hyperlipidemia, hypercholesterolemia and atherosclerotic diseases by reducing cholesterol level and anti-lipid properties. Importantly, simvastatin has also been reported to have anti-tumor effect, but the underlying mechanism is largely unknown. We collected several human bladder samples and performed microarray. Data analysis suggested bladder cancer (BCa) was significantly associated with fatty acid/lipid metabolism via PPAR signalling pathway. We observed simvastatin did not trigger BCa cell apoptosis, but reduced cell proliferation in a dose- and time-dependent manner, accompanied by PPARγ-activation. Moreover, flow cytometry analysis indicated that simvastatin induced cell cycle arrest at G0/G1 phase, suggested by downregulation of CDK4/6 and Cyclin D1. Furthermore, simvastatin suppressed BCa cell metastasis by inhibiting EMT and affecting AKT/GSK3β. More importantly, we found that the cell cycle arrest at G0/G1 phase and the alterations of CDK4/6 and Cyclin D1 triggered by simvastatin could be recovered by PPARγ-antagonist (GW9662), whereas the treatment of PPARα-antagonist (GW6471) shown no significant effects on the BCa cells. Taken together, our study for the first time revealed that simvastatin inhibited bladder cancer cell proliferation and induced cell cycle arrest at G1/G0 phase via PPARγ signalling pathway. PMID:27779188

  5. SLIT/ROBO2 Signaling Promotes Mammary Stem Cell Senescence by Inhibiting Wnt Signaling

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    Gwyndolen Harburg

    2014-09-01

    Full Text Available WNT signaling stimulates the self-renewal of many types of adult stem cells, including mammary stem cells (MaSCs, but mechanisms that limit this activity are poorly understood. Here, we demonstrate that SLIT2 restricts stem cell renewal by signaling through ROBO2 in a subset of basal cells to negatively regulate WNT signaling. The absence of SLIT/ROBO2 signaling leads to increased levels of nuclear β-catenin. Robo2 loss does not increase the number of stem cells; instead, stem cell renewal is enhanced in the absence of SLIT/ROBO2 signaling. This is due to repressed expression of p16 INK4a, which, in turn, delays MaSC senescence. Together, our studies support a model in which SLITs restrict the expansion of MaSCs by countering the activity of WNTs and limiting self-renewal.

  6. Inhibition of Gli/hedgehog signaling in prostate cancer cells by "cancer bush" Sutherlandia frutescens extract.

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    Lin, Hui; Jackson, Glenn A; Lu, Yuan; Drenkhahn, Sara K; Brownstein, Korey J; Starkey, Nicholas J; Lamberson, William R; Fritsche, Kevin L; Mossine, Valeri V; Besch-Williford, Cynthia L; Folk, William R; Zhang, Yong; Lubahn, Dennis B

    2016-02-01

    Sutherlandia frutescens is a medicinal plant, traditionally used to treat various types of human diseases, including cancer. Previous studies of several botanicals link suppression of prostate cancer growth with inhibition of the Gli/hedgehog (Gli/Hh) signaling pathway. Here we hypothesized the anti-cancer effect of S. frutescens was linked to its inhibition of the Gli/Hh signaling in prostate cancer. We found a dose- and time-dependent growth inhibition in human prostate cancer cells, PC3 and LNCaP, and mouse prostate cancer cell, TRAMP-C2, treated with S. frutescens methanol extract (SLE). We also observed a dose-dependent inhibition of the Gli-reporter activity in Shh Light II and TRAMP-C2QGli cells treated with SLE. In addition, SLE can inhibit Gli/Hh signaling by blocking Gli1 and Ptched1 gene expression in the presence of a Gli/Hh signaling agonist (SAG). A diet supplemented with S. frutescens suppressed the formation of poorly differentiated carcinoma in prostates of TRAMP mice. Finally, we found Sutherlandioside D was the most potent compound in the crude extract that could suppress Gli-reporter in Shh Light II cells. Together, this suggests that the S. frutescens extract may exert anti-cancer effect by targeting Gli/Hh signaling, and Sutherlandioside D is one of the active compounds. PMID:26377232

  7. Inhibition of tankyrases induces Axin stabilization and blocks Wnt signalling in breast cancer cells.

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    Renyue Bao

    Full Text Available Constitutive Wnt signalling is characterized by excessive levels of β-catenin protein and is a frequent occurrence in cancer. APC and Axin are key components of the β-catenin destruction complex that acts to promote β-catenin degradation. The levels of Axin are in turn controlled by tankyrases, members of the PARP-family of poly-ADP-ribosylation enzymes. In colorectal cancer cells, which typically harbor APC mutations, inhibition of tankyrase activity promotes Axin stabilization and attenuates Wnt signalling. Here, we examined the effect of inhibiting tankyrases in breast cancer cells with normal APC. We show that application of the small molecule tankyrase inhibitor, XAV939 or siRNA-mediated abrogation of tankyrase expression increases Axin1 and Axin2 protein levels and attenuates Wnt-induced transcriptional responses in several breast cancer lines. In MDA-MB-231 cells, inhibiton of tankyrase activity also attenuate Wnt3a induced cell migration. Moreover, in both MDA-MB-231 and colorectal cancer cells, XAV939 inhibits cell growth under conditions of serum-deprivation. However, the presence of serum prevents this growth inhibitory effect, although inhibition of Wnt-induced transcriptional and migratory responses was maintained. These results indicate that stabilization of Axin by inhibition of tankyrases alone, may not be an effective means to block tumor cell growth and that combinatorial therapeutic approaches should be considered.

  8. Targeting Stem Cell Behavior in Desmoid Tumors (Aggressive Fibromatosis by Inhibiting Hedgehog Signaling

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    Ronak Ghanbari-Azarnier

    2013-07-01

    Full Text Available Desmoid tumor (also called aggressive fibromatosis is a lesion of mesenchymal origin that can occur as a sporadic tumor or a manifestation of the preneoplastic syndrome, familial adenomatous polyposis caused by a mutation in adenomatous polyposis coli (APC. This tumor type is characterized by the stabilization of β-catenin and activation of Tcf-mediated transcription. Cell transplantation data suggest that desmoid tumors are derived from mesenchymal progenitor cells (MSCs. As such, modulating cell signaling pathways that regulate MSC differentiation or proliferation, such as hedgehog (Hh signaling, could alter the tumor phenotype. Here, we found that Hh signaling is activated in human and murine desmoid tumors. Inhibiting Hh signaling in human cell cultures decreased cell proliferation and β-catenin protein levels. Apc+/Apc1638N mice, which develop desmoid tumors, develop smaller and fewer tumors when Hh signaling was inhibited either genetically (by crossing Apc+/Apc1638N mice with mice lacking one copy of a Hh-activated transcription factor, Gli2+/-mice or using a pharmacologic inhibitor. Both in mice and in human tumor cell cultures, β-catenin and Hh-mediated signaling positively regulate each other's activity. These data show that targeting a pathway that regulates MSC differentiation influences desmoid tumor behavior, providing functional evidence supporting the notion that these tumors are derived from mesenchymal progenitors. It also suggests Hh blockade as a therapeutic approach for this tumor type.

  9. 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

  10. Peptide p277 of HSP60 signals T cells: inhibition of inflammatory chemotaxis.

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    Nussbaum, Gabriel; Zanin-Zhorov, Alexandra; Quintana, Francisco; Lider, Ofer; Cohen, Irun R

    2006-10-01

    Peptide p277 is a 24-amino acid fragment of the heat shock protein 60 molecule, first discovered to be an antigen for diabetogenic T-cell clones in non-obese diabetic (NOD) mice. Therapeutic vaccination with p277 can arrest the spontaneous diabetogenic process both in NOD mice and in humans associated with a T(h)1 to T(h)2 cytokine shift specific for the autoimmune T cells. We now report that p277 can directly signal human T cells via innate toll-like receptor (TLR)-2, leading to up-regulation of integrin-mediated adhesion to fibronectin, and inhibition of chemotaxis to the chemokine SDF-1alpha in vitro. Resting CD45RA(+) T cells responded to lower concentrations of p277 than resting CD45RO(+) T cells, but activation of CD45RO(+) T cells greatly increased their sensitivity to p277. Mouse T cells, but not macrophages, were also sensitive to the innate effects of peptide p277, and adoptive transfer of diabetes by splenic T cells from NOD mice could be inhibited by p277 treatment before transfer. Thus, T cells do respond innately to p277, and signaling by soluble p277 through TLR2 could contribute to the treatment of type 1 diabetes; p277 may stop the destruction of beta cells by signaling in concert both innate and adaptive receptors on T cells. PMID:16893923

  11. Saw Palmetto Extract Inhibits Metastasis and Antiangiogenesis through STAT3 Signal Pathway in Glioma Cell

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    Hong Ding

    2015-01-01

    Full Text Available Signal transducer and activator of transcription factor 3 (STAT3 plays an important role in the proliferation and angiogenesis in human glioma. Previous research indicated that saw palmetto extract markedly inhibited the proliferation of human glioma cells through STAT3 signal pathway. But its effect on tumor metastasis and antiangiogenesis is not clear. This study is to further clear the impact of saw palmetto extract on glioma cell metastasis, antiangiogenesis, and its mechanism. TUNEL assay indicated that the apoptotic cells in the saw palmetto treated group are higher than that in the control group (p<0.05. The apoptosis related protein is detected and the results revealed that saw palmetto extract inhibits the proliferation of human glioma. Meanwhile pSTAT3 is lower in the experimental group and CD34 is also inhibited in the saw palmetto treated group. This means that saw palmetto extract could inhibit the angiogenesis in glioma. We found that saw palmetto extract was an important phytotherapeutic drug against the human glioma through STAT3 signal pathway. Saw palmetto extract may be useful as an adjunctive therapeutic agent for treatment of individuals with glioma and other types of cancer in which STAT3 signaling is activated.

  12. Lithium inhibits tumorigenic potential of PDA cells through targeting hedgehog-GLI signaling pathway.

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    Zhonglu Peng

    Full Text Available Hedgehog signaling pathway plays a critical role in the initiation and development of pancreatic ductal adenocarcinoma (PDA and represents an attractive target for PDA treatment. Lithium, a clinical mood stabilizer for mental disorders, potently inhibits the activity of glycogen synthase kinase 3β (GSK3β that promotes the ubiquitin-dependent proteasome degradation of GLI1, an important downstream component of hedgehog signaling. Herein, we report that lithium inhibits cell proliferation, blocks G1/S cell-cycle progression, induces cell apoptosis and suppresses tumorigenic potential of PDA cells through down-regulation of the expression and activity of GLI1. Moreover, lithium synergistically enhances the anti-cancer effect of gemcitabine. These findings further our knowledge of mechanisms of action for lithium and provide a potentially new therapeutic strategy for PDA through targeting GLI1.

  13. Dendritic cell derived IL-2 inhibits survival of terminally mature cells via an autocrine signaling pathway.

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    Balachander, Akhila; Nabti, Sabrina; Sobota, Radoslaw M; Foo, Shihui; Zolezzi, Francesca; Lee, Bernett T K; Poidinger, Michael; Ricciardi-Castagnoli, Paola

    2015-05-01

    DCs are crucial for sensing pathogens and triggering immune response. Upon activation by pathogen-associated molecular pattern (PAMP) ligands, GM-CSF myeloid DCs (GM-DCs) secrete several cytokines, including IL-2. DC IL-2 has been shown to be important for innate and adaptive immune responses; however, IL-2 importance in DC physiology has never been demonstrated. Here, we show that autocrine IL-2 signaling is functional in murine GM-DCs in an early time window after PAMPs stimulation. IL-2 signaling selectively activates the JAK/STAT5 pathway by assembling holo-receptor complexes at the cell surface. Using the sensitivity of targeted mass spectrometry, we show conclusively that GM-DCs express CD122, the IL-2 receptor β-chain, at steady state. In myeloid DCs, this cytokine pathway inhibits survival of PAMP-matured GM-DCs which is crucial for maintaining immune tolerance and preventing autoimmunity. Our findings suggest that immune regulation by this novel autocrine signaling pathway can potentially be used in DC immunotherapy. PMID:25652593

  14. FK866-induced NAMPT inhibition activates AMPK and downregulates mTOR signaling in hepatocarcinoma cells

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    Schuster, Susanne, E-mail: Susanne.Schuster@medizin.uni-leipzig.de [Center for Pediatric Research Leipzig, University Hospital for Children and Adolescents, Faculty of Medicine, University of Leipzig, Liebigstr. 21, 04103 Leipzig (Germany); Penke, Melanie; Gorski, Theresa [Center for Pediatric Research Leipzig, University Hospital for Children and Adolescents, Faculty of Medicine, University of Leipzig, Liebigstr. 21, 04103 Leipzig (Germany); Gebhardt, Rolf [Institute of Biochemistry, Faculty of Medicine, University of Leipzig, Johannisallee 30, 04103 Leipzig (Germany); Weiss, Thomas S. [Children' s University Hospital, University of Regensburg, Franz-Josef-Strauss-Allee 11, 93053 Regensburg (Germany); Kiess, Wieland; Garten, Antje [Center for Pediatric Research Leipzig, University Hospital for Children and Adolescents, Faculty of Medicine, University of Leipzig, Liebigstr. 21, 04103 Leipzig (Germany)

    2015-03-06

    Background: Nicotinamide phosphoribosyltransferase (NAMPT) is the key enzyme of the NAD salvage pathway starting from nicotinamide. Cancer cells have an increased demand for NAD due to their high proliferation and DNA repair rate. Consequently, NAMPT is considered as a putative target for anti-cancer therapies. There is evidence that AMP-activated protein kinase (AMPK) and mammalian target of rapamycin (mTOR) become dysregulated during the development of hepatocellular carcinoma (HCC). Here, we investigated the effects of NAMPT inhibition by its specific inhibitor FK866 on the viability of hepatocarcinoma cells and analyzed the effects of FK866 on the nutrient sensor AMPK and mTOR complex1 (mTORC1) signaling. Results: FK866 markedly decreased NAMPT activity and NAD content in hepatocarcinoma cells (Huh7 cells, Hep3B cells) and led to delayed ATP reduction which was associated with increased cell death. These effects could be abrogated by administration of nicotinamide mononucleotide (NMN), the enzyme product of NAMPT. Our results demonstrated a dysregulation of the AMPK/mTOR pathway in hepatocarcinoma cells compared to non-cancerous hepatocytes with a higher expression of mTOR and a lower AMPKα activation in hepatocarcinoma cells. We found that NAMPT inhibition by FK866 significantly activated AMPKα and inhibited the activation of mTOR and its downstream targets p70S6 kinase and 4E-BP1 in hepatocarcinoma cells. Non-cancerous hepatocytes were less sensitive to FK866 and did not show changes in AMPK/mTOR signaling after FK866 treatment. Conclusion: Taken together, these findings reveal an important role of the NAMPT-mediated NAD salvage pathway in the energy homeostasis of hepatocarcinoma cells and suggest NAMPT inhibition as a potential treatment option for HCC. - Highlights: • FK866 increases cell death in p53-deficient hepatocarcinoma cells. • AMPK/mTOR signaling is dysregulated in hepatocarcinoma cells. • FK866-induced NAMPT inhibition activates AMPK

  15. Epigallocatechin gallate inhibits the proliferation of colorectal cancer cells by regulating Notch signaling

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    Jin H

    2013-03-01

    Full Text Available Heiying Jin,1,* Wei Gong,2,* Chunxia Zhang,1,* Shuiming Wang1 1National Center of Colorectal Surgery, the Third Affiliated Hospital of Nanjing University of Traditional Chinese Medicine, Nanjing, People’s Republic of China; 2Department of Surgery, Jiangyin Hospital of Traditional Chinese Medicine, Jiangsu, People's Republic of China*These authors contributed equally to this workAims: To explore the inhibitory effects of epigallocatechin gallate (EGCG on the proliferation of colorectal cancer cells and on the gene expression of Notch signaling.Methods: The colorectal cancer cells and orthotopic colorectal cancer transplant model were treated with EGCG, and MTT assay was used to test the inhibitory role of EGCG in the proliferation of colorectal cancer cells. Results: MTT assay indicated that EGCG inhibited the proliferation of these four cell lines when the time and concentration increased, and EGCG enhanced the apoptotic rate of these four cell lines. The dosage was positively correlated to the apoptotic rate, and EGCG inhibited the proliferation of colorectal cancer cells by influencing cell cycle. In-vivo study suggested that on the seventh day, the volume of tumors reduced after administrating with 5, 10 and 20 mg/kg of EGCG. At the twenty-eighth day, the volume of tumors was significantly different in three EGCG treatment groups as compared to the control group (P < 0.05, and TUNEL assay indicated that the apoptosis of cancer cells in EGCG treated groups was markedly higher than that in the control group (P < 0.05. In these cell lines, the expressions of HES1 and Notch2 in EGCG treated groups were remarkably lower than that in the control group (P < 0.05. The expression of JAG1 decreased in SW480 cells (P = 0.019, HT-29 cells and HCT-8 cells, but increased in LoVo cells at mRNA level. The expression of Notch1 was upregulated in these four cell lines, but its expression was significantly upregulated only in LoVo and SW480 cells (P < 0

  16. Fully human antagonistic antibodies against CCR4 potently inhibit cell signaling and chemotaxis.

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    Urs B Hagemann

    Full Text Available CC chemokine receptor 4 (CCR4 represents a potentially important target for cancer immunotherapy due to its expression on tumor infiltrating immune cells including regulatory T cells (Tregs and on tumor cells in several cancer types and its role in metastasis.Using phage display, human antibody library, affinity maturation and a cell-based antibody selection strategy, the antibody variants against human CCR4 were generated. These antibodies effectively competed with ligand binding, were able to block ligand-induced signaling and cell migration, and demonstrated efficient killing of CCR4-positive tumor cells via ADCC and phagocytosis. In a mouse model of human T-cell lymphoma, significant survival benefit was demonstrated for animals treated with the newly selected anti-CCR4 antibodies.For the first time, successful generation of anti- G-protein coupled chemokine receptor (GPCR antibodies using human non-immune library and phage display on GPCR-expressing cells was demonstrated. The generated anti-CCR4 antibodies possess a dual mode of action (inhibition of ligand-induced signaling and antibody-directed tumor cell killing. The data demonstrate that the anti-tumor activity in vivo is mediated, at least in part, through Fc-receptor dependent effector mechanisms, such as ADCC and phagocytosis. Anti-CC chemokine receptor 4 antibodies inhibiting receptor signaling have potential as immunomodulatory antibodies for cancer.

  17. Triptolide inhibits TGF-β1-induced cell proliferation in rat airway smooth muscle cells by suppressing Smad signaling

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    Chen, Ming; Lv, Zhiqiang; Huang, Linjie [Department of Respiratory Medicine, Sun Yat-Sen Memorial Hospital, Institute for Respiratory disease of Sun Yat-sen University, Sun Yat-sen University, Guangzhou, Guangdong Province 510120 (China); Zhang, Wei [Department of Geratology, the Second People' s Hospital of Shenzhen, Shenzhen 518000 (China); Lin, Xiaoling; Shi, Jianting; Zhang, Wei; Liang, Ruiyun [Department of Respiratory Medicine, Sun Yat-Sen Memorial Hospital, Institute for Respiratory disease of Sun Yat-sen University, Sun Yat-sen University, Guangzhou, Guangdong Province 510120 (China); Jiang, Shanping, E-mail: shanpingjiang@126.com [Department of Respiratory Medicine, Sun Yat-Sen Memorial Hospital, Institute for Respiratory disease of Sun Yat-sen University, Sun Yat-sen University, Guangzhou, Guangdong Province 510120 (China)

    2015-02-15

    Background: We have reported that triptolide can inhibit airway remodeling in a murine model of asthma via TGF-β1/Smad signaling. In the present study, we aimed to investigate the effect of triptolide on airway smooth muscle cells (ASMCs) proliferation and the possible mechanism. Methods: Rat airway smooth muscle cells were cultured and made synchronized, then pretreated with different concentration of triptolide before stimulated by TGF-β1. Cell proliferation was evaluated by MTT assay. Flow cytometry was used to study the influence of triptolide on cell cycle and apoptosis. Signal proteins (Smad2, Smad3 and Smad7) were detected by western blotting analysis. Results: Triptolide significantly inhibited TGF-β1-induced ASMC proliferation (P<0.05). The cell cycle was blocked at G1/S-interphase by triptolide dose dependently. No pro-apoptotic effects were detected under the concentration of triptolide we used. Western blotting analysis showed TGF-β1 induced Smad2 and Smad3 phosphorylation was inhibited by triptolide pretreatment, and the level of Smad7 was increased by triptolide pretreatment. Conclusions: Triptolide may function as an inhibitor of asthma airway remodeling by suppressing ASMCs proliferation via negative regulation of Smad signaling pathway. - Highlights: • In this study, rat airway smooth muscle cells were cultured and made synchronized. • Triptolide inhibited TGF-β1-induced airway smooth muscle cells proliferation. • Triptolide inhibited ASMCs proliferation via negative regulation of Smad signaling pathway.

  18. Inhibition of NF-κB promotes autophagy via JNK signaling pathway in porcine granulosa cells.

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    Gao, Hui; Lin, Lu; Haq, Ihtesham Ul; Zeng, Shen-Ming

    2016-04-22

    The transcription factor nuclear factor-κB (NF-κB) plays an important role in diverse processes, including cell proliferation and differentiation, apoptosis and inflammation. However, the role of NF-κB in porcine follicle development is not clearly elucidated. In this study, we demonstrated that follicle stimulating hormone (FSH) increased the level of inhibitor of NF-κB (IκB) protein and promoted the cytoplasmic localization of p65, indicating that FSH inhibits the activation of NF-κB in porcine granulosa cells. Moreover, inhibition of NF-κB by FSH or another specific inhibitor of NF-κB, pyrrolidine dithiocarbamate (PDTC), could activate JNK signaling and enhance autophagic activity in porcine granulosa cells. Knockdown of RelA (p65) Subunit of NF-κB by RNA interference abrogated the activation of JNK signaling pathway and the increase of autophagic protein expression by FSH. Meanwhile, the functional significance of FSH or PDTC-mediated autophagy were further investigated. Our results demonstrated that the increased autophagy promoted progesterone secretion in porcine granulosa cells. Blockage of autophagy by chloroquine obviated the FSH or PDTC-induced progesterone production. Taken together, these results indicate that inhibition of NF-κB increased autophagy via JNK signaling, and promote steroidogenesis in porcine granulosa cells. Our results provide new insights into the regulation and function of autophagy in mammalian follicle development. PMID:27016483

  19. Thyroid hormone inhibits the proliferation of piglet Sertoli cell via PI3K signaling pathway.

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    Sun, Yan; Yang, WeiRong; Luo, HongLin; Wang, XianZhong; Chen, ZhongQiong; Zhang, JiaoJiao; Wang, Yi; Li, XiaoMin

    2015-01-01

    Accumulating researches show that thyroid hormone (TH) inhibits Sertoli cells (SCs) proliferation and stimulates their functional maturation in prepubertal rat testis, confirming that TH plays a key role in testicular development. However, the mechanism under the T3 regulation of piglet SC proliferation remains unclear. In the present study, in order to investigate the possible mechanism of T3 on the suppression of SC proliferation, the expression pattern of TRα1 and cell cycle-related molecules, effect of T3 on SC proliferation, and the role of phosphoinositide 3-kinase (PI3K)/Akt signaling pathway on the T3-mediated SC proliferation in piglet testis were explored. Our results demonstrated that TRα1 was expressed in all tested stages of SCs and decreased along with the ages. T3 inhibited the proliferation of SCs in a time- and dose-dependent manner, and T3 treatment downregulated the expressions of cell cycling molecules, such as cyclinA2, cyclinD1, cyclinE1, PCNA, and Skp2, but upregulated the p27 expression in SCs. Most importantly, the suppressive effects of T3 on SC proliferation seemed dependent on the inhibition of PI3K/Akt signaling pathway, and pre-stimulation of PI3K could enhance such suppressive effects. Together, our findings demonstrate that TH inhibits the proliferation of piglet SCs via the suppression of PI3K/Akt signaling pathway.

  20. Inhibition of TGF-β Signaling Promotes Human Pancreatic β-Cell Replication.

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    Dhawan, Sangeeta; Dirice, Ercument; Kulkarni, Rohit N; Bhushan, Anil

    2016-05-01

    Diabetes is associated with loss of functional pancreatic β-cells, and restoration of β-cells is a major goal for regenerative therapies. Endogenous regeneration of β-cells via β-cell replication has the potential to restore cellular mass; however, pharmacological agents that promote regeneration or expansion of endogenous β-cells have been elusive. The regenerative capacity of β-cells declines rapidly with age, due to accumulation of p16(INK4a), resulting in limited capacity for adult endocrine pancreas regeneration. Here, we show that transforming growth factor-β (TGF-β) signaling via Smad3 integrates with the trithorax complex to activate and maintain Ink4a expression to prevent β-cell replication. Importantly, inhibition of TGF-β signaling can result in repression of the Ink4a/Arf locus, resulting in increased β-cell replication in adult mice. Furthermore, small molecule inhibitors of the TGF-β pathway promote β-cell replication in human islets transplanted into NOD-scid IL-2Rg(null) mice. These data reveal a novel role for TGF-β signaling in the regulation of the Ink4a/Arf locus and highlight the potential of using small molecule inhibitors of TGF-β signaling to promote human β-cell replication. PMID:26936960

  1. Inhibition of TGF-β signaling in normal lung epithelial cells confers resistance to ionizing radiation

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    Reeves, Anna; Zagurovskaya, Marianna; Gupta, Seema; Shareef, Mohammed M.; Mohiuddin, Mohammed; Ahmed, Mansoor M.

    2007-01-01

    Purpose To address the functional role of radiation-induced TGF-β signaling in normal epithelial background, we selected spontaneously immortalized lung epithelial cell line derived from the normal lung tissue of dominant-negative mutant of TGF-β RII (ΔRII) transgenic mouse that expressed conditionally ΔRII under the control of metallothionein promoter (MT-1) and assessed it's impact on radio-sensitivity. Method and Materials Spontaneously immortalized lung epithelial cell culture (SILECC) was established and all analyses were performed within 50 passages. Colony-forming and TUNEL assays were used to assess the clonogenic inhibition and apoptosis respectively. Western blot analysis was performed to assess the kinetics of p21, bax and RII proteins. TGF-β responsive promoter activity was measured using dual-luciferase reporter assay. Results Exposure to ZnSO4 inhibited TGF-β signaling induced either by recombinant TGF-β1 or ionizing radiation. SILECC treated either with ZnSO4 or neutralizing antibody against TGF-β showed a significant increase in radio-resistance when compared to untreated cells. Furthermore, the expression of the ΔRII inhibited the radiation-induced up-regulation of the TGF-β effector gene p21waf1/cip1.. Conclusions Our findings imply that inhibition of radiation-induced TGF-β signaling via abrogation of RII function enhances radio-resistance of the normal lung epithelial cells, and this can be directly attributed to the loss of TGF-β signaling function. PMID:17448872

  2. Propentofylline inhibits glioblastoma cell invasion and survival by targeting the TROY signaling pathway.

    Science.gov (United States)

    Dhruv, Harshil D; Roos, Alison; Tomboc, Patrick J; Tuncali, Serdar; Chavez, Ashley; Mathews, Ian; Berens, Michael E; Loftus, Joseph C; Tran, Nhan L

    2016-02-01

    Glioblastoma (GBM) is the most common primary tumor of the CNS and carries a dismal prognosis. The aggressive invasion of GBM cells into the surrounding normal brain makes complete resection impossible, significantly increases resistance to the standard therapy regimen, and virtually assures tumor recurrence. Median survival for newly diagnosed GBM is 14.6 months and declines to 8 months for patients with recurrent GBM. New therapeutic strategies that target the molecular drivers of invasion are required for improved clinical outcome. We have demonstrated that TROY (TNFRSF19), a member of the TNFR super-family, plays an important role in GBM invasion and resistance. Knockdown of TROY expression inhibits GBM cell invasion, increases sensitivity to temozolomide, and prolongs survival in an intracranial xenograft model. Propentofylline (PPF), an atypical synthetic methylxanthine compound, has been extensively studied in Phase II and Phase III clinical trials for Alzheimer's disease and vascular dementia where it has demonstrated blood-brain permeability and minimal adverse side effects. Here we showed that PPF decreased GBM cell expression of TROY, inhibited glioma cell invasion, and sensitized GBM cells to TMZ. Mechanistically, PPF decreased glioma cell invasion by modulating TROY expression and downstream signaling, including AKT, NF-κB, and Rac1 activation. Thus, PPF may provide a pharmacologic approach to target TROY, inhibit cell invasion, and reduce therapeutic resistance in GBM. PMID:26559543

  3. Kalkitoxin Inhibits Angiogenesis, Disrupts Cellular Hypoxic Signaling, and Blocks Mitochondrial Electron Transport in Tumor Cells

    Directory of Open Access Journals (Sweden)

    J. Brian Morgan

    2015-03-01

    Full Text Available The biologically active lipopeptide kalkitoxin was previously isolated from the marine cyanobacterium Moorea producens (Lyngbya majuscula. Kalkitoxin exhibited N-methyl-d-aspartate (NMDA-mediated neurotoxicity and acted as an inhibitory ligand for voltage-sensitive sodium channels in cultured rat cerebellar granule neurons. Subsequent studies revealed that kalkitoxin generated a delayed form of colon tumor cell cytotoxicity in 7-day clonogenic cell survival assays. Cell line- and exposure time-dependent cytostatic/cytotoxic effects were previously observed with mitochondria-targeted inhibitors of hypoxia-inducible factor-1 (HIF-1. The transcription factor HIF-1 functions as a key regulator of oxygen homeostasis. Therefore, we investigated the ability of kalkitoxin to inhibit hypoxic signaling in human tumor cell lines. Kalkitoxin potently and selectively inhibited hypoxia-induced activation of HIF-1 in T47D breast tumor cells (IC50 5.6 nM. Mechanistic studies revealed that kalkitoxin inhibits HIF-1 activation by suppressing mitochondrial oxygen consumption at electron transport chain (ETC complex I (NADH-ubiquinone oxidoreductase. Further studies indicate that kalkitoxin targets tumor angiogenesis by blocking the induction of angiogenic factors (i.e., VEGF in tumor cells.

  4. Delphinidin Inhibits Tumor Growth by Acting on VEGF Signalling in Endothelial Cells.

    Directory of Open Access Journals (Sweden)

    Thérèse Keravis

    Full Text Available The vasculoprotective properties of delphinidin are driven mainly by its action on endothelial cells. Moreover, delphinidin displays anti-angiogenic properties in both in vitro and in vivo angiogenesis models and thereby might prevent the development of tumors associated with excessive vascularization. This study was aimed to test the effect of delphinidin on melanoma-induced tumor growth with emphasis on its molecular mechanism on endothelial cells. Delphinidin treatment significantly decreased in vivo tumor growth induced by B16-F10 melanoma cell xenograft in mice. In vitro, delphinidin was not able to inhibit VEGFR2-mediated B16-F10 melanoma cell proliferation but it specifically reduced basal and VEGFR2-mediated endothelial cell proliferation. The anti-proliferative effect of delphinidin was reversed either by the MEK1/2 MAP kinase inhibitor, U-0126, or the PI3K inhibitor, LY-294002. VEGF-induced proliferation was reduced either by U-0126 or LY-294002. Under these conditions, delphinidin failed to decrease further endothelial cell proliferation. Delphinidin prevented VEGF-induced phosphorylation of ERK1/2 and p38 MAPK and decreased the expression of the transcription factors, CREB and ATF1. Finally, delphinidin was more potent in inhibiting in vitro cyclic nucleotide phosphodiesterases (PDEs, PDE1 and PDE2, compared to PDE3-PDE5. Altogether delphinidin reduced tumor growth of melanoma cell in vivo by acting specifically on endothelial cell proliferation. The mechanism implies an association between inhibition of VEGF-induced proliferation via VEGFR2 signalling, MAPK, PI3K and at transcription level on CREB/ATF1 factors, and the inhibition of PDE2. In conjunction with our previous studies, we demonstrate that delphinidin is a promising compound to prevent pathologies associated with generation of vascular network in tumorigenesis.

  5. BDNF/TrkB signaling protects HT-29 human colon cancer cells from EGFR inhibition

    International Nuclear Information System (INIS)

    Highlights: ► BDNF protected HT-29 colorectal cancer cells from the antitumor effect of cetuximab. ► TrkB inhibition potentiated the antitumor effect of cetuximab. ► BDNF/TrkB signaling might be involved in resistance to anti-EGFR therapy. -- Abstract: The clinical success of targeted treatment of colorectal cancer (CRC) is often limited by resistance to anti-epidermal growth factor receptor (EGFR) therapy. The neurotrophin brain-derived neurotrophic factor (BDNF) and its receptor TrkB have recently emerged as anticancer targets, and we have previously shown increased BDNF levels in CRC tumor samples. Here we report the findings from in vitro experiments suggesting that BDNF/TrkB signaling can protect CRC cells from the antitumor effects of EGFR blockade. The anti-EGFR monoclonal antibody cetuximab reduced both cell proliferation and the mRNA expression of BDNF and TrkB in human HT-29 CRC cells. The inhibitory effect of cetuximab on cell proliferation and survival was counteracted by the addition of human recombinant BDNF. Finally, the Trk inhibitor K252a synergistically enhanced the effect of cetuximab on cell proliferation, and this effect was blocked by BDNF. These results provide the first evidence that increased BDNF/TrkB signaling might play a role in resistance to EGFR blockade. Moreover, it is possible that targeting TrkB could potentiate the anticancer effects of anti-EGFR therapy.

  6. BDNF/TrkB signaling protects HT-29 human colon cancer cells from EGFR inhibition

    Energy Technology Data Exchange (ETDEWEB)

    Brunetto de Farias, Caroline [Cancer Research Laboratory, University Hospital Research Center (CPE-HCPA), Federal University of Rio Grande do Sul, 90035-003 Porto Alegre, RS (Brazil); Children' s Cancer Institute, 90420-140 Porto Alegre, RS (Brazil); Laboratory of Neuropharmacology and Neural Tumor Biology, Department of Pharmacology, Institute for Basic Health Sciences, Federal University of Rio Grande do Sul, 90050-170 Porto Alegre, RS (Brazil); National Institute for Translational Medicine (INCT-TM), 90035-003 Porto Alegre, RS (Brazil); Heinen, Tiago Elias; Pereira dos Santos, Rafael [Cancer Research Laboratory, University Hospital Research Center (CPE-HCPA), Federal University of Rio Grande do Sul, 90035-003 Porto Alegre, RS (Brazil); Laboratory of Neuropharmacology and Neural Tumor Biology, Department of Pharmacology, Institute for Basic Health Sciences, Federal University of Rio Grande do Sul, 90050-170 Porto Alegre, RS (Brazil); National Institute for Translational Medicine (INCT-TM), 90035-003 Porto Alegre, RS (Brazil); Abujamra, Ana Lucia [Cancer Research Laboratory, University Hospital Research Center (CPE-HCPA), Federal University of Rio Grande do Sul, 90035-003 Porto Alegre, RS (Brazil); Children' s Cancer Institute, 90420-140 Porto Alegre, RS (Brazil); National Institute for Translational Medicine (INCT-TM), 90035-003 Porto Alegre, RS (Brazil); Schwartsmann, Gilberto [Cancer Research Laboratory, University Hospital Research Center (CPE-HCPA), Federal University of Rio Grande do Sul, 90035-003 Porto Alegre, RS (Brazil); National Institute for Translational Medicine (INCT-TM), 90035-003 Porto Alegre, RS (Brazil); Department of Internal Medicine, School of Medicine, Federal University of Rio Grande do Sul, 90035-003 Porto Alegre, RS (Brazil); and others

    2012-08-24

    Highlights: Black-Right-Pointing-Pointer BDNF protected HT-29 colorectal cancer cells from the antitumor effect of cetuximab. Black-Right-Pointing-Pointer TrkB inhibition potentiated the antitumor effect of cetuximab. Black-Right-Pointing-Pointer BDNF/TrkB signaling might be involved in resistance to anti-EGFR therapy. -- Abstract: The clinical success of targeted treatment of colorectal cancer (CRC) is often limited by resistance to anti-epidermal growth factor receptor (EGFR) therapy. The neurotrophin brain-derived neurotrophic factor (BDNF) and its receptor TrkB have recently emerged as anticancer targets, and we have previously shown increased BDNF levels in CRC tumor samples. Here we report the findings from in vitro experiments suggesting that BDNF/TrkB signaling can protect CRC cells from the antitumor effects of EGFR blockade. The anti-EGFR monoclonal antibody cetuximab reduced both cell proliferation and the mRNA expression of BDNF and TrkB in human HT-29 CRC cells. The inhibitory effect of cetuximab on cell proliferation and survival was counteracted by the addition of human recombinant BDNF. Finally, the Trk inhibitor K252a synergistically enhanced the effect of cetuximab on cell proliferation, and this effect was blocked by BDNF. These results provide the first evidence that increased BDNF/TrkB signaling might play a role in resistance to EGFR blockade. Moreover, it is possible that targeting TrkB could potentiate the anticancer effects of anti-EGFR therapy.

  7. Hedgehog signaling antagonist GDC-0449 (Vismodegib inhibits pancreatic cancer stem cell characteristics: molecular mechanisms.

    Directory of Open Access Journals (Sweden)

    Brahma N Singh

    Full Text Available BACKGROUND: Recent evidence from in vitro and in vivo studies has demonstrated that aberrant reactivation of the Sonic Hedgehog (SHH signaling pathway regulates genes that promote cellular proliferation in various human cancer stem cells (CSCs. Therefore, the chemotherapeutic agents that inhibit activation of Gli transcription factors have emerged as promising novel therapeutic drugs for pancreatic cancer. GDC-0449 (Vismodegib, orally administrable molecule belonging to the 2-arylpyridine class, inhibits SHH signaling pathway by blocking the activities of Smoothened. The objectives of this study were to examine the molecular mechanisms by which GDC-0449 regulates human pancreatic CSC characteristics in vitro. METHODOLOGY/PRINCIPAL FINDINGS: GDC-0499 inhibited cell viability and induced apoptosis in three pancreatic cancer cell lines and pancreatic CSCs. This inhibitor also suppressed cell viability, Gli-DNA binding and transcriptional activities, and induced apoptosis through caspase-3 activation and PARP cleavage in pancreatic CSCs. GDC-0449-induced apoptosis in CSCs showed increased Fas expression and decreased expression of PDGFRα. Furthermore, Bcl-2 was down-regulated whereas TRAIL-R1/DR4 and TRAIL-R2/DR5 expression was increased following the treatment of CSCs with GDC-0449. Suppression of both Gli1 plus Gli2 by shRNA mimicked the changes in cell viability, spheroid formation, apoptosis and gene expression observed in GDC-0449-treated pancreatic CSCs. Thus, activated Gli genes repress DRs and Fas expressions, up-regulate the expressions of Bcl-2 and PDGFRα and facilitate cell survival. CONCLUSIONS/SIGNIFICANCE: These data suggest that GDC-0499 can be used for the management of pancreatic cancer by targeting pancreatic CSCs.

  8. K-channels inhibited by hydrogen peroxide mediate abscisic acid signaling in Vicia guard cells

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    A number of studies show that environmental stress conditions increase abscisic acid (ABA) and hydrogen peroxide (H2O2) levels in plant cells. Despite this central role of ABA in altering stomatal aperture by regulating guard cell ion transport, little is known concerning the relationship between ABA and H2O2 in signal transduction leading to stomatal movement. Epidermal strip bioassay illustrated that ABA-inhibited stomatal opening and ABA-induced stomatal closure were abolished partly by externally added catalase (CAT) or diphenylene iodonium (DPI), which are a H2O2 scavenger and a NADPH oxidase inhibitor respectively. In contrast, internally added CAT or DPI nearly completely or partly reversed ABA-induced closure in half-stoma. Consistent with these results, whole-cell patch-clamp analysis showed that intracellular application of CAT or DPI partly abolished ABA-inhibited inward K+ current across the plasma membrane of guard cells. H2O2 mimicked ABA to inhibit inward K+ current, an effect which was reversed by the addition of ascorbic acid (Vc) in patch clamping micropipettes. These results suggested that H2O2 mediated ABA-induced stomatal movement by targeting inward K+ channels at plasma membrane.

  9. Intracellular autocrine VEGF signaling promotes EBDC cell proliferation, which can be inhibited by Apatinib.

    Science.gov (United States)

    Peng, Sui; Zhang, Yanyan; Peng, Hong; Ke, Zunfu; Xu, Lixia; Su, Tianhong; Tsung, Allan; Tohme, Samer; Huang, Hai; Zhang, Qiuyang; Lencioni, Riccardo; Zeng, Zhirong; Peng, Baogang; Chen, Minhu; Kuang, Ming

    2016-04-10

    Tumor cells produce vascular endothelial growth factor (VEGF) which can interact with membrane or cytoplasmic VEGF receptors (VEGFRs) to promote cell growth. We aimed to investigate the role of extracellular/intracellular autocrine VEGF signaling and Apatinib, a highly selective VEGFR2 inhibitor, in extrahepatic bile duct cancer (EBDC). We found conditioned medium or recombinant human VEGF treatment promoted EBDC cell proliferation through a phospholipase C-γ1-dependent pathway. This pro-proliferative effect was diminished by VEGF, VEGFR1 or VEGFR2 neutralizing antibodies, but more significantly suppressed by intracellular VEGFR inhibitor. The rhVEGF induced intracellular VEGF signaling by promoting nuclear accumulation of pVEGFR1/2 and enhancing VEGF promoter activity, mRNA and protein expression. Internal VEGFR2 inhibitor Apatinib significantly inhibited intracellular VEGF signaling, suppressed cell proliferation in vitro and delayed xenograft tumor growth in vivo, while anti-VEGF antibody Bevacizumab showed no effect. Clinically, overexpression of pVEGFR1 and pVEGFR2 was significantly correlated with poorer overall survival (P = .007 and P = .020, respectively). In conclusion, the intracellular autocrine VEGF loop plays a predominant role in VEGF-induced cell proliferation. Apatinib is an effective intracellular VEGF pathway blocker that presents a great therapeutic potential in EBDC. PMID:26805764

  10. Silybin-mediated inhibition of Notch signaling exerts antitumor activity in human hepatocellular carcinoma cells.

    Directory of Open Access Journals (Sweden)

    Song Zhang

    Full Text Available Hepatocellular carcinoma (HCC is a global health burden that is associated with limited treatment options and poor patient prognoses. Silybin (SIL, an antioxidant derived from the milk thistle plant (Silybum marianum, has been reported to exert hepatoprotective and antitumorigenic effects both in vitro and in vivo. While SIL has been shown to have potent antitumor activity against various types of cancer, including HCC, the molecular mechanisms underlying the effects of SIL remain largely unknown. The Notch signaling pathway plays crucial roles in tumorigenesis and immune development. In the present study, we assessed the antitumor activity of SIL in human HCC HepG2 cells in vitro and in vivo and explored the roles of the Notch pathway and of the apoptosis-related signaling pathway on the activity of SIL. SIL treatment resulted in a dose- and time-dependent inhibition of HCC cell viability. Additionally, SIL exhibited strong antitumor activity, as evidenced not only by reductions in tumor cell adhesion, migration, intracellular glutathione (GSH levels and total antioxidant capability (T-AOC but also by increases in the apoptotic index, caspase3 activity, and reactive oxygen species (ROS. Furthermore, SIL treatment decreased the expression of the Notch1 intracellular domain (NICD, RBP-Jκ, and Hes1 proteins, upregulated the apoptosis pathway-related protein Bax, and downregulated Bcl2, survivin, and cyclin D1. Notch1 siRNA (in vitro or DAPT (a known Notch1 inhibitor, in vivo further enhanced the antitumor activity of SIL, and recombinant Jagged1 protein (a known Notch ligand in vitro attenuated the antitumor activity of SIL. Taken together, these data indicate that SIL is a potent inhibitor of HCC cell growth that targets the Notch signaling pathway and suggest that the inhibition of Notch signaling may be a novel therapeutic intervention for HCC.

  11. Sulforaphene Interferes with Human Breast Cancer Cell Migration and Invasion through Inhibition of Hedgehog Signaling.

    Science.gov (United States)

    Bao, Cheng; Kim, Min Chae; Chen, Jing; Song, Jieun; Ko, Hyuk Wan; Lee, Hong Jin

    2016-07-13

    Although inhibition of mammary tumorigenesis by isothiocyanates has been widely studied, little is known about the effects of sulforaphene on invasiveness of breast cancer. Here, sulforaphene significantly inhibited the migration and invasion of triple-negative SUM159 human breast cancer cells and suppressed the expression and activity of matrix metalloproteinases 2 and 9 (MMP-2 and MMP-9). The Hedgehog (Hh) pathway, as an upstream signaling modulator, was significantly suppressed by sulforaphene. In particular, ciliary localization of Gli1 and its nuclear translocation were blocked by sulforaphene in a time-dependent manner. Consistently, downregulation of Hh signaling by vismodegib and Gli1 knockdown reduced the cellular migration and invasion as well as the expression of MMP-2 and MMP-9. These results indicate that the suppression of Hh/Gli1 signaling by sulforaphene may reduce the MMP-2 and MMP-9 activities and cellular invasiveness of human breast cancer cells, suggesting the potential efficacy of sulforaphene against breast cancer invasion and metastasis. PMID:27327035

  12. Andrographolide suppresses epithelial mesenchymal transition by inhibition of MAPK signalling pathway in lens epithelial cells

    Indian Academy of Sciences (India)

    Forum Kayastha; Kaid Johar; Devarshi Gajjar; Anshul Arora; Hardik Madhu; Darshini Ganatra; Abhay Vasavada

    2015-06-01

    Epithelial mesenchymal transition (EMT) of lens epithelial cells (LECs) may contribute to the development of posterior capsular opacification (PCO), which leads to visual impairment. Andrographolide has been shown to have therapeutic potential against various cancers. However, its effect on human LECs is still unknown. The purpose of this study is to evaluate the effect of andrographolide on EMT induced by growth factors in the fetal human lens epithelial cell line (FHL 124). Initially the LECs were treated with growth factors (TGF-2 and bFGF) to induce EMT. Subsequently these EMT-induced cells were treated with andrographolide at 100 and 500 nM concentrations for 24 h. Our results showed that FHL 124 cells treated with growth factors had a significant decrease in protein and m-RNA levels of epithelial markers pax6 and E-Cadherin. After administering andrographolide, these levels significantly increased. It was noticed that EMT markers -SMA, fibronectin and collagen IV significantly decreased after treatment with andrographolide when compared to the other group. Treatment with andrographolide significantly inhibited phosphorylation of ERK and JNK. Cell cycle analysis showed that andrographolide did not arrest cells at G0/G1 or G2/M at tested concentrations. Our findings suggest that andrographolide helps sustain epithelial characteristics by modulating EMT markers and inhibiting the mitogen-activated protein kinase (MAPK) signalling pathway in LECs. Hence it can prove to be useful in curbing EMT-mediated PCO.

  13. Andrographolide suppresses epithelial mesenchymal transition by inhibition of MAPK signalling pathway in lens epithelial cells.

    Science.gov (United States)

    Kayastha, Forum; Johar, Kaid; Gajjar, Devarshi; Arora, Anshul; Madhu, Hardik; Ganatra, Darshini; Vasavada, Abhay

    2015-06-01

    Epithelial mesenchymal transition (EMT) of lens epithelial cells (LECs) may contribute to the development of posterior capsular opacification (PCO), which leads to visual impairment. Andrographolide has been shown to have therapeutic potential against various cancers. However, its effect on human LECs is still unknown. The purpose of this study is to evaluate the effect of andrographolide on EMT induced by growth factors in the fetal human lens epithelial cell line (FHL 124). Initially the LECs were treated with growth factors (TGF-beta 2 and bFGF) to induce EMT. Subsequently these EMT-induced cells were treated with andrographolide at 100 and 500 nM concentrations for 24 h. Our results showed that FHL 124 cells treated with growth factors had a significant decrease in protein and m-RNA levels of epithelial markers pax6 and E-Cadherin. After administering andrographolide, these levels significantly increased. It was noticed that EMT markers alpha-SMA, fibronectin and collagen IV significantly decreased after treatment with andrographolide when compared to the other group. Treatment with andrographolide significantly inhibited phosphorylation of ERK and JNK. Cell cycle analysis showed that andrographolide did not arrest cells at G0/G1 or G2/M at tested concentrations. Our findings suggest that andrographolide helps sustain epithelial characteristics by modulating EMT markers and inhibiting the mitogen-activated protein kinase (MAPK) signalling pathway in LECs. Hence it can prove to be useful in curbing EMT-mediated PCO. PMID:25963259

  14. Indole-3-carbinol, a vegetable phytochemical, inhibits adipogenesis by regulating cell cycle and AMPKα signaling.

    Science.gov (United States)

    Choi, Hyeon-Son; Jeon, Hui-Jeon; Lee, Ok-Hwan; Lee, Boo-Yong

    2014-09-01

    Indole-3-carbinol (I3C) is a phytochemical present mainly in cruciferous vegetables. In this study, we investigated the mechanism by which I3C blocks adipogenesis in 3T3-L1 cells, and evaluated the anti-adipogenic effect of I3C in zebrafish. Our data showed that I3C mainly inhibits early differentiation of adipocyte through cell cycle arrest. Inhibition of early differentiation was reflected by down-regulation of early adipogenic factors such as CCAAT-enhancer binding proteins β and δ (C/EBPβ and C/EBPδ), followed by down-regulation of late adipogenic factors such as peroxisome proliferator-activated receptor γ (PPARγ) and C/EBPα, and regulation of signaling molecules. This result was supported by a reduction in triglyceride (TG) levels and TG synthetic enzymes. I3C activated AMP-activated protein kinase α (AMPKα) to inhibit fatty acid synthesis. In addition, an anti-adipogenic effect of I3C was found in zebrafish study. Our data suggest that vegetables-derived I3C could reduce lipid accumulation via various molecular mechanisms in cell.

  15. Desipramine inhibits histamine H1 receptor-induced Ca2+ signaling in rat hypothalamic cells.

    Directory of Open Access Journals (Sweden)

    Ji-Ah Kang

    Full Text Available The hypothalamus in the brain is the main center for appetite control and integrates signals from adipose tissue and the gastrointestinal tract. Antidepressants are known to modulate the activities of hypothalamic neurons and affect food intake, but the cellular and molecular mechanisms by which antidepressants modulate hypothalamic function remain unclear. Here we have investigated how hypothalamic neurons respond to treatment with antidepressants, including desipramine and sibutramine. In primary cultured rat hypothalamic cells, desipramine markedly suppressed the elevation of intracellular Ca(2+ evoked by histamine H1 receptor activation. Desipramine also inhibited the histamine-induced Ca(2+ increase and the expression of corticotrophin-releasing hormone in hypothalamic GT1-1 cells. The effect of desipramine was not affected by pretreatment with prazosin or propranolol, excluding catecholamine reuptake activity of desipramine as an underlying mechanism. Sibutramine which is also an antidepressant but decreases food intake, had little effect on the histamine-induced Ca(2+ increase or AMP-activated protein kinase activity. Our results reveal that desipramine and sibutramine have different effects on histamine H1 receptor signaling in hypothalamic cells and suggest that distinct regulation of hypothalamic histamine signaling might underlie the differential regulation of food intake between antidepressants.

  16. Piperlongumine inhibits atherosclerotic plaque formation and vascular smooth muscle cell proliferation by suppressing PDGF receptor signaling

    Energy Technology Data Exchange (ETDEWEB)

    Son, Dong Ju [Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA (United States); Division of Cardiology, Department of Medicine, Emory University, Atlanta, GA (United States); Kim, Soo Yeon [Division of Life Science, Korea Basic Science Institute, Daejeon (Korea, Republic of); Han, Seong Su [University of Iowa Carver College of Medicine, Department of Pathology, Iowa City, IA (United States); Kim, Chan Woo [Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA (United States); Division of Cardiology, Department of Medicine, Emory University, Atlanta, GA (United States); Department of Bioinspired Science, Ehwa Womans University, Seoul (Korea, Republic of); Kumar, Sandeep [Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA (United States); Division of Cardiology, Department of Medicine, Emory University, Atlanta, GA (United States); Park, Byeoung Soo [Nanotoxtech Co., Ansan (Korea, Republic of); Lee, Sung Eun [Division of Applied Biology and Chemistry, Kyungpook National University, Daegu (Korea, Republic of); Yun, Yeo Pyo [College of Pharmacy, Chungbuk National University, Cheongju (Korea, Republic of); Jo, Hanjoong, E-mail: hjo@emory.edu [Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA (United States); Division of Cardiology, Department of Medicine, Emory University, Atlanta, GA (United States); Department of Bioinspired Science, Ehwa Womans University, Seoul (Korea, Republic of); Park, Young Hyun, E-mail: pyh012@sch.ac.kr [Department of Food Science and Nutrition, College of Natural Sciences, Soonchunhyang University, Asan (Korea, Republic of)

    2012-10-19

    Highlights: Black-Right-Pointing-Pointer Anti-atherogenic effect of PL was examined using partial carotid ligation model in ApoE KO mice. Black-Right-Pointing-Pointer PL prevented atherosclerotic plaque development, VSMCs proliferation, and NF-{kappa}B activation. Black-Right-Pointing-Pointer Piperlongumine reduced vascular smooth muscle cell activation through PDGF-R{beta} and NF-{kappa}B-signaling. Black-Right-Pointing-Pointer PL may serve as a new therapeutic molecule for atherosclerosis treatment. -- Abstract: Piperlongumine (piplartine, PL) is an alkaloid found in the long pepper (Piper longum L.) and has well-documented anti-platelet aggregation, anti-inflammatory, and anti-cancer properties; however, the role of PL in prevention of atherosclerosis is unknown. We evaluated the anti-atherosclerotic potential of PL in an in vivo murine model of accelerated atherosclerosis and defined its mechanism of action in aortic vascular smooth muscle cells (VSMCs) in vitro. Local treatment with PL significantly reduced atherosclerotic plaque formation as well as proliferation and nuclear factor-kappa B (NF-{kappa}B) activation in an in vivo setting. PL treatment in VSMCs in vitro showed inhibition of migration and platelet-derived growth factor BB (PDGF-BB)-induced proliferation to the in vivo findings. We further identified that PL inhibited PDGF-BB-induced PDGF receptor beta activation and suppressed downstream signaling molecules such as phospholipase C{gamma}1, extracellular signal-regulated kinases 1 and 2 and Akt. Lastly, PL significantly attenuated activation of NF-{kappa}B-a downstream transcriptional regulator in PDGF receptor signaling, in response to PDGF-BB stimulation. In conclusion, our findings demonstrate a novel, therapeutic mechanism by which PL suppresses atherosclerosis plaque formation in vivo.

  17. Tetramethylpyrazine Inhibits Activation of Hepatic Stellate Cells through Hedgehog Signaling Pathways In Vitro

    Directory of Open Access Journals (Sweden)

    Jue Hu

    2015-01-01

    Full Text Available Background and Aim. Tetramethylpyrazine (TMP, a major alkaloid isolated from Ligusticum chuanxiong, has been reported in hepatic fibrosis models. However, the action mechanism remains unclear. In the present study, effects of tetramethylpyrazine (TMP against hepatic stellate cell (HSC activation as well as the possible mechanisms were evaluated. Methods. Western blot assay was used to detect TMP effects on protein expression of Smo, Patched, Hhip, and Gli and to investigate the effects of TMP on Cyclin D1, Cyclin E1, CDK2, Bcl-2, Bax, and caspase expression with cyclopamine supplementation. Results. Our results showed that TMP significantly inhibits the expression of Cyclin D1, Cyclin E1, and Cyclin-dependent kinase CDK2 and changes the HSC cycle by inhibiting the proliferation of HSC. Moreover, TMP has also been shown to decrease the expression of Bcl-2 and increase the expression of Bax in HSC-T6 cells. Furthermore, TMP can inhibit the expression of connective tissue growth factor (CTGF, and the inhibitory effect was intensified after the application of joint treatment with TMP and cyclopamine. Conclusion. TMP may be an effective Hh signaling pathway inhibitor for hepatic fibrosis treatment.

  18. LRP-1 promotes cancer cell invasion by supporting ERK and inhibiting JNK signaling pathways.

    Directory of Open Access Journals (Sweden)

    Benoit Langlois

    Full Text Available BACKGROUND: The low-density lipoprotein receptor-related protein-1 (LRP-1 is an endocytic receptor mediating the clearance of various extracellular molecules involved in the dissemination of cancer cells. LRP-1 thus appeared as an attractive receptor for targeting the invasive behavior of malignant cells. However, recent results suggest that LRP-1 may facilitate the development and growth of cancer metastases in vivo, but the precise contribution of the receptor during cancer progression remains to be elucidated. The lack of mechanistic insights into the intracellular signaling networks downstream of LRP-1 has prevented the understanding of its contribution towards cancer. METHODOLOGY/PRINCIPAL FINDINGS: Through a short-hairpin RNA-mediated silencing approach, we identified LRP-1 as a main regulator of ERK and JNK signaling in a tumor cell context. Co-immunoprecipitation experiments revealed that LRP-1 constitutes an intracellular docking site for MAPK containing complexes. By using pharmacological agents, constitutively active and dominant-negative kinases, we demonstrated that LRP-1 maintains malignant cells in an adhesive state that is favorable for invasion by activating ERK and inhibiting JNK. We further demonstrated that the LRP-1-dependent regulation of MAPK signaling organizes the cytoskeletal architecture and mediates adhesive complex turnover in cancer cells. Moreover, we found that LRP-1 is tethered to the actin network and to focal adhesion sites and controls ERK and JNK targeting to talin-rich structures. CONCLUSIONS: We identified ERK and JNK as the main molecular relays by which LRP-1 regulates focal adhesion disassembly of malignant cells to support invasion.

  19. Targeting IL-8 signalling to inhibit breast cancer stem cell activity.

    Science.gov (United States)

    Singh, Jagdeep K; Simões, Bruno M; Clarke, Robert B; Bundred, Nigel J

    2013-11-01

    Although survival from breast cancer has improved significantly over the past 20 years, disease recurrence remains a significant clinical problem. The concept of stem-like cells in cancer has been gaining currency over the last decade or so, since evidence for stem cell activity in human leukaemia and solid tumours, including breast cancer, was first published. Evidence indicates that this sub-population of cells, known as cancer stem-like cells (CSCs), is responsible for driving tumour formation and disease progression. In breast cancer, there is good evidence that CSCs are intrinsically resistant to conventional chemo-, radio- and endocrine therapies. By evading the effects of these treatments, CSCs are held culpable for disease recurrence. Hence, in order to improve treatment there is a need to develop CSC-targeted therapies. Interleukin-8 (IL-8), an inflammatory cytokine, is upregulated in breast cancer and associated with poor prognostic factors. Accumulating evidence demonstrates that IL-8, through its receptors CXCR1/2, is an important regulator of breast CSC activity. Inhibiting CXCR1/2 signalling has proved efficacious in pre-clinical models of breast cancer providing a good rationale for targeting CXCR1/2 clinically. Here, we discuss the role of IL-8 in breast CSC regulation and development of novel therapies to target CXCR1/2 signalling in breast cancer.

  20. 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

  1. 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.

  2. Effect of soluble Jagged1-mediated inhibition of Notch signaling on proliferation and differentiation of an adipocyte progenitor cell model

    OpenAIRE

    Urs, Sumithra; Turner, Bryce; Tang, Yuefeng; Rostama, Bahman; Small, Deena; Liaw, Lucy

    2012-01-01

    Adipose tissue development is dependent on multiple signaling mechanisms and cell-cell interactions that regulate adipogenesis, angiogenesis and extracellular remodeling. The Notch signaling pathway is an important cell-fate determinant whose role in adipogenesis is not clearly defined. To address this issue, we examined the effect of inhibition of Notch signaling by soluble-Jagged1 in the 3T3-L1 preadipocyte line. In vitro, soluble-Jagged1 expression in 3T3-L1 cells altered cell morphology, ...

  3. Heparin-disaccharide affects T cells: inhibition of NF-kappaB activation, cell migration, and modulation of intracellular signaling.

    Science.gov (United States)

    Hecht, Iris; Hershkoviz, Rami; Shivtiel, Shoham; Lapidot, Tzvi; Cohen, Irun R; Lider, Ofer; Cahalon, Liora

    2004-06-01

    We previously reported that disaccharides (DS), generated by enzymatic degradation of heparin or heparan sulfate, inhibit T cell-mediated immune reactions in rodents and regulate cytokine [tumor necrosis factor alpha (TNF-alpha), interleukin (IL)-8, and IL-1beta] secretion by T cells, macrophages, or intestinal epithelial cells. Here, we investigated the effects of a trisulfated heparin DS (3S-DS) on two aspects of T cell function: secretion of proinflammatory cytokines and migration to an inflamed site. 3S-DS down-regulated nuclear factor-kappaB activity and reduced the secretion of TNF-alpha and interferon-gamma (IFN-gamma) by anti-CD3-activated T cells. In addition, 3S-DS inhibited CXC chemokine ligand 12 (CXCL12; stromal cell-derived factor-1alpha)-dependent migration in vitro and in vivo and decreased CXCL12-induced T cell adhesion to the extracellular matrix glycoprotein, fibronectin (FN). This inhibition was accompanied by attenuation of CXCL12-induced Pyk2 phosphorylation but did not involve internalization of the CXCL12 receptor, CXCR4, or phosphorylation of extracellular-regulated kinase. Despite inhibiting CXCL12-induced adhesion, 3S-DS, on its own, induced T cell adhesion to FN, which was accompanied by phosphorylation of Pyk2. A monosulfated DS showed no effect. Taken together, these data provide evidence that 3S-DS can regulate inflammation by inducing and modulating T cell-signaling events, desensitizing CXCR4, and modulating T cell receptor-induced responses. PMID:15020655

  4. Pentoxifylline Inhibits WNT Signalling in β-Cateninhigh Patient-Derived Melanoma Cell Populations

    Science.gov (United States)

    Talar, Beata; Gajos-Michniewicz, Anna; Talar, Marcin; Chouaib, Salem; Czyz, Malgorzata

    2016-01-01

    Background The heterogeneity of melanoma needs to be addressed and combination therapies seem to be necessary to overcome intrinsic and acquired resistance to newly developed immunotherapies and targeted therapies. Although the role of WNT/β-catenin pathway in melanoma was early demonstrated, its contribution to the lack of the melanoma patient response to treatment was only recently recognized. Using patient-derived melanoma cell populations, we investigated the influence of pentoxifylline on melanoma cells with either high or low expression of β-catenin. Findings Our results indicate that pentoxifylline inhibits the activity of the canonical WNT pathway in melanoma cell populations with high basal activity of this signalling. This is supported by lowered overall activity of transcription factors TCF/LEF and reduced nuclear localisation of active β-catenin. Moreover, treatment of β-cateninhigh melanoma cell populations with pentoxifylline induces downregulation of genes that are targets of the WNT/β-catenin pathway including connective tissue growth factor (CTGF) and microphthalmia-associated transcription factor (MITF-M), a melanocyte- and melanoma cell-specific regulator. Conclusions These results suggest that pentoxifylline, a drug approved by the FDA in the treatment of peripheral arterial disease, might be tested in a subset of melanoma patients with elevated activity of β-catenin. This pharmaceutical might be tested as an adjuvant drug in combination therapies when the response to immunotherapy is prevented by high activity of the WNT/β-catenin pathway. PMID:27351373

  5. Pentoxifylline Inhibits WNT Signalling in β-Cateninhigh Patient-Derived Melanoma Cell Populations.

    Directory of Open Access Journals (Sweden)

    Beata Talar

    Full Text Available The heterogeneity of melanoma needs to be addressed and combination therapies seem to be necessary to overcome intrinsic and acquired resistance to newly developed immunotherapies and targeted therapies. Although the role of WNT/β-catenin pathway in melanoma was early demonstrated, its contribution to the lack of the melanoma patient response to treatment was only recently recognized. Using patient-derived melanoma cell populations, we investigated the influence of pentoxifylline on melanoma cells with either high or low expression of β-catenin.Our results indicate that pentoxifylline inhibits the activity of the canonical WNT pathway in melanoma cell populations with high basal activity of this signalling. This is supported by lowered overall activity of transcription factors TCF/LEF and reduced nuclear localisation of active β-catenin. Moreover, treatment of β-cateninhigh melanoma cell populations with pentoxifylline induces downregulation of genes that are targets of the WNT/β-catenin pathway including connective tissue growth factor (CTGF and microphthalmia-associated transcription factor (MITF-M, a melanocyte- and melanoma cell-specific regulator.These results suggest that pentoxifylline, a drug approved by the FDA in the treatment of peripheral arterial disease, might be tested in a subset of melanoma patients with elevated activity of β-catenin. This pharmaceutical might be tested as an adjuvant drug in combination therapies when the response to immunotherapy is prevented by high activity of the WNT/β-catenin pathway.

  6. Role of satellite cells versus myofibers in muscle hypertrophy induced by inhibition of the myostatin/activin signaling pathway

    OpenAIRE

    Lee, Se-Jin; Huynh, Thanh V.; Lee, Yun-Sil; Sebald, Suzanne M.; Wilcox-Adelman, Sarah A.; Iwamori, Naoki; Lepper, Christoph; Matzuk, Martin M.; Fan, Chen-Ming

    2012-01-01

    Myostatin and activin A are structurally related secreted proteins that act to limit skeletal muscle growth. The cellular targets for myostatin and activin A in muscle and the role of satellite cells in mediating muscle hypertrophy induced by inhibition of this signaling pathway have not been fully elucidated. Here we show that myostatin/activin A inhibition can cause muscle hypertrophy in mice lacking either syndecan4 or Pax7, both of which are important for satellite cell function and devel...

  7. Neural Inhibition of Dopaminergic Signaling Enhances Immunity in a Cell-Non-autonomous Manner.

    Science.gov (United States)

    Cao, Xiou; Aballay, Alejandro

    2016-09-12

    The innate immune system is the front line of host defense against microbial infections, but its rapid and uncontrolled activation elicits microbicidal mechanisms that have deleterious effects [1, 2]. Increasing evidence indicates that the metazoan nervous system, which responds to stimuli originating from both the internal and the external environment, functions as a modulatory apparatus that controls not only microbial killing pathways but also cellular homeostatic mechanisms [3-5]. Here we report that dopamine signaling controls innate immune responses through a D1-like dopamine receptor, DOP-4, in Caenorhabditis elegans. Chlorpromazine inhibition of DOP-4 in the nervous system activates a microbicidal PMK-1/p38 mitogen-activated protein kinase signaling pathway that enhances host resistance against bacterial infections. The immune inhibitory function of dopamine originates in CEP neurons and requires active DOP-4 in downstream ASG neurons. Our findings indicate that dopamine signaling from the nervous system controls immunity in a cell-non-autonomous manner and identifies the dopaminergic system as a potential therapeutic target for not only infectious diseases but also a range of conditions that arise as a consequence of malfunctioning immune responses.

  8. Glycerol Monolaurate (GML) inhibits human T cell signaling and function by disrupting lipid dynamics.

    Science.gov (United States)

    Zhang, Michael S; Sandouk, Aline; Houtman, Jon C D

    2016-01-01

    Glycerol Monolaurate (GML) is a naturally occurring fatty acid widely utilized in food, cosmetics, and homeopathic supplements. GML is a potent antimicrobial agent that targets a range of bacteria, fungi, and enveloped viruses but select findings suggest that GML also has immunomodulatory functions. In this study, we have mechanistically examined if GML affects the signaling and functional output of human primary T cells. We found that GML potently altered order and disorder dynamics in the plasma membrane that resulted in reduced formation of LAT, PLC-γ, and AKT microclusters. Altered membrane events induced selective inhibition of TCR-induced phosphorylation of regulatory P85 subunit of PI3K and AKT as well as abrogated calcium influx. Ultimately, GML treatment potently reduced TCR-induced production of IL-2, IFN-γ, TNF-α, and IL-10. Our data reveal that the widely used anti-microbial agent GML also alters the lipid dynamics of human T cells, leading to their defective signaling and function. PMID:27456316

  9. Glycerol Monolaurate (GML) inhibits human T cell signaling and function by disrupting lipid dynamics

    Science.gov (United States)

    Zhang, Michael S.; Sandouk, Aline; Houtman, Jon C. D.

    2016-01-01

    Glycerol Monolaurate (GML) is a naturally occurring fatty acid widely utilized in food, cosmetics, and homeopathic supplements. GML is a potent antimicrobial agent that targets a range of bacteria, fungi, and enveloped viruses but select findings suggest that GML also has immunomodulatory functions. In this study, we have mechanistically examined if GML affects the signaling and functional output of human primary T cells. We found that GML potently altered order and disorder dynamics in the plasma membrane that resulted in reduced formation of LAT, PLC-γ, and AKT microclusters. Altered membrane events induced selective inhibition of TCR-induced phosphorylation of regulatory P85 subunit of PI3K and AKT as well as abrogated calcium influx. Ultimately, GML treatment potently reduced TCR-induced production of IL-2, IFN-γ, TNF-α, and IL-10. Our data reveal that the widely used anti-microbial agent GML also alters the lipid dynamics of human T cells, leading to their defective signaling and function. PMID:27456316

  10. Notch signalling inhibits CD4 expression during initiation and differentiation of human T cell lineage.

    Directory of Open Access Journals (Sweden)

    Stephen M Carlin

    Full Text Available The Delta/Notch signal transduction pathway is central to T cell differentiation from haemopoietic stem cells (HSCs. Although T cell development is well characterized using expression of cell surface markers, the detailed mechanisms driving differentiation have not been established. This issue becomes central with observations that adult HSCs exhibit poor differentiation towards the T cell lineage relative to neonatal or embryonic precursors. This study investigates the contribution of Notch signalling and stromal support cells to differentiation of adult and Cord Blood (CB human HSCs, using the Notch signalling OP9Delta co-culture system. Co-cultured cells were assayed at weekly intervals during development for phenotype markers using flow cytometry. Cells were also assayed for mRNA expression at critical developmental stages. Expression of the central thymocyte marker CD4 was initiated independently of Notch signalling, while cells grown with Notch signalling had reduced expression of CD4 mRNA and protein. Interruption of Notch signalling in partially differentiated cells increased CD4 mRNA and protein expression, and promoted differentiation to CD4(+ CD8(+ T cells. We identified a set of genes related to T cell development that were initiated by Notch signalling, and also a set of genes subsequently altered by Notch signal interruption. These results demonstrate that while Notch signalling is essential for establishment of the T cell lineage, at later stages of differentiation, its removal late in differentiation promotes more efficient DP cell generation. Notch signalling adds to signals provided by stromal cells to allow HSCs to differentiate to T cells via initiation of transcription factors such as HES1, GATA3 and TCF7. We also identify gene expression profile differences that may account for low generation of T cells from adult HSCs.

  11. Quercetin suppresses insulin receptor signaling through inhibition of the insulin ligand–receptor binding and therefore impairs cancer cell proliferation

    International Nuclear Information System (INIS)

    Graphical abstract: - Highlights: • Quercetin inhibits insulin ligand–receptor interactions. • Quercetin reduces downstream insulin receptor signaling. • Quercetin blocks insulin induced glucose uptake. • Quercetin suppresses insulin stimulated cancer cell proliferation and tumor growth. - Abstract: Although the flavonoid quercetin is known to inhibit activation of insulin receptor signaling, the inhibitory mechanism is largely unknown. In this study, we demonstrate that quercetin suppresses insulin induced dimerization of the insulin receptor (IR) through interfering with ligand–receptor interactions, which reduces the phosphorylation of IR and Akt. This inhibitory effect further inhibits insulin stimulated glucose uptake due to decreased cell membrane translocation of glucose transporter 4 (GLUT4), resulting in impaired cancer cell proliferation. The effect of quercetin in inhibiting tumor growth was also evident in an in vivo model, indicating a potential future application for quercetin in the treatment of cancers

  12. Quercetin suppresses insulin receptor signaling through inhibition of the insulin ligand–receptor binding and therefore impairs cancer cell proliferation

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Feng [Department of Gastroenterology, The Tenth People’s Hospital of Shanghai, Tongji University, Shanghai 200072 (China); Department of Nanomedicine, Houston Methodist Research Institute, Houston, TX 77030 (United States); Yang, Yong, E-mail: yyang@houstonmethodist.org [Department of Nanomedicine, Houston Methodist Research Institute, Houston, TX 77030 (United States); Department of Medicine, Weill Cornell Medical College, New York, NY 10065 (United States)

    2014-10-03

    Graphical abstract: - Highlights: • Quercetin inhibits insulin ligand–receptor interactions. • Quercetin reduces downstream insulin receptor signaling. • Quercetin blocks insulin induced glucose uptake. • Quercetin suppresses insulin stimulated cancer cell proliferation and tumor growth. - Abstract: Although the flavonoid quercetin is known to inhibit activation of insulin receptor signaling, the inhibitory mechanism is largely unknown. In this study, we demonstrate that quercetin suppresses insulin induced dimerization of the insulin receptor (IR) through interfering with ligand–receptor interactions, which reduces the phosphorylation of IR and Akt. This inhibitory effect further inhibits insulin stimulated glucose uptake due to decreased cell membrane translocation of glucose transporter 4 (GLUT4), resulting in impaired cancer cell proliferation. The effect of quercetin in inhibiting tumor growth was also evident in an in vivo model, indicating a potential future application for quercetin in the treatment of cancers.

  13. Dibenzocyclooctadiene lignans, gomisins J and N inhibit the Wnt/{beta}-catenin signaling pathway in HCT116 cells

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Kyungsu; Lee, Kyung-Mi; Yoo, Ji-Hye; Lee, Hee Ju [Functional Food Center, Korea Institute of Science and Technology, Gangneung 210-340 (Korea, Republic of); Kim, Chul Young [Functional Food Center, Korea Institute of Science and Technology, Gangneung 210-340 (Korea, Republic of); College of Pharmacy, Hanyang University, Ansan 426-791 (Korea, Republic of); Nho, Chu Won, E-mail: cwnho@kist.re.kr [Functional Food Center, Korea Institute of Science and Technology, Gangneung 210-340 (Korea, Republic of)

    2012-11-16

    Graphical abstract: Schematic diagram of the possible molecular mechanism underlying the inhibition of the Wnt/{beta}-catenin signaling pathway and the induction of G0/G1-phase arrest by gomisins J and N, derived from the fruits of S. chinensis, in HCT116 human colon cancer cells. Highlights: Black-Right-Pointing-Pointer Gomisins J and N inhibited Wnt/{beta}-catenin signaling pathway in HCT116 cells. Black-Right-Pointing-Pointer Gomisins J and N disrupted the binding of {beta}-catenin to specific DNA sequences, TBE. Black-Right-Pointing-Pointer Gomisins J and N inhibited the HCT116 cell proliferation through G0/G1 phase arrest. Black-Right-Pointing-Pointer Gomisins J and N inhibited the expression of Cyc D1, a Wnt/{beta}-catenin target gene. -- Abstract: Here, we report that gomisin J and gomisin N, dibenzocyclooctadiene type lignans isolated from Schisandra chinensis, inhibit Wnt/{beta}-catenin signaling in HCT116 cells. Gomisins J and N appear to inhibit Wnt/{beta}-catenin signaling by disrupting the interaction between {beta}-catenin and its specific target DNA sequences (TCF binding elements, TBE) rather than by altering the expression of the {beta}-catenin protein. Gomisins J and N inhibit HCT116 cell proliferation by arresting the cell cycle at the G0/G1 phase. The G0/G1 phase arrest induced by gomisins J and N appears to be caused by a decrease in the expression of Cyclin D1, a representative target gene of the Wnt/{beta}-catenin signaling pathway, as well as Cdk2, Cdk4, and E2F-1. Therefore, gomisins J and N, the novel Wnt/{beta}-catenin inhibitors discovered in this study, may serve as potential agents for the prevention and treatment of human colorectal cancers.

  14. Coordinated control of Notch/Delta signalling and cell cycle progression drives lateral inhibition-mediated tissue patterning

    Science.gov (United States)

    Hadjivasiliou, Zena; Bonin, Hope; He, Li; Perrimon, Norbert; Charras, Guillaume; Baum, Buzz

    2016-01-01

    Coordinating cell differentiation with cell growth and division is crucial for the successful development, homeostasis and regeneration of multicellular tissues. Here, we use bristle patterning in the fly notum as a model system to explore the regulatory and functional coupling of cell cycle progression and cell fate decision-making. The pattern of bristles and intervening epithelial cells (ECs) becomes established through Notch-mediated lateral inhibition during G2 phase of the cell cycle, as neighbouring cells physically interact with each other via lateral contacts and/or basal protrusions. Since Notch signalling controls cell division timing downstream of Cdc25, ECs in lateral contact with a Delta-expressing cell experience higher levels of Notch signalling and divide first, followed by more distant neighbours, and lastly Delta-expressing cells. Conversely, mitotic entry and cell division makes ECs refractory to lateral inhibition signalling, fixing their fate. Using a combination of experiments and computational modelling, we show that this reciprocal relationship between Notch signalling and cell cycle progression acts like a developmental clock, providing a delimited window of time during which cells decide their fate, ensuring efficient and orderly bristle patterning. PMID:27226324

  15. Coordinated control of Notch/Delta signalling and cell cycle progression drives lateral inhibition-mediated tissue patterning.

    Science.gov (United States)

    Hunter, Ginger L; Hadjivasiliou, Zena; Bonin, Hope; He, Li; Perrimon, Norbert; Charras, Guillaume; Baum, Buzz

    2016-07-01

    Coordinating cell differentiation with cell growth and division is crucial for the successful development, homeostasis and regeneration of multicellular tissues. Here, we use bristle patterning in the fly notum as a model system to explore the regulatory and functional coupling of cell cycle progression and cell fate decision-making. The pattern of bristles and intervening epithelial cells (ECs) becomes established through Notch-mediated lateral inhibition during G2 phase of the cell cycle, as neighbouring cells physically interact with each other via lateral contacts and/or basal protrusions. Since Notch signalling controls cell division timing downstream of Cdc25, ECs in lateral contact with a Delta-expressing cell experience higher levels of Notch signalling and divide first, followed by more distant neighbours, and lastly Delta-expressing cells. Conversely, mitotic entry and cell division makes ECs refractory to lateral inhibition signalling, fixing their fate. Using a combination of experiments and computational modelling, we show that this reciprocal relationship between Notch signalling and cell cycle progression acts like a developmental clock, providing a delimited window of time during which cells decide their fate, ensuring efficient and orderly bristle patterning. PMID:27226324

  16. Brevilin A, a novel natural product, inhibits janus kinase activity and blocks STAT3 signaling in cancer cells.

    Directory of Open Access Journals (Sweden)

    Xing Chen

    Full Text Available Signal abnormalities in human cells usually cause unexpected consequences for individual health. We focus on these kinds of events involved in JAK-STAT signal pathways, especially the ones triggered by aberrant activated STAT3, an oncoprotein which participates in essential processes of cell survival, growth and proliferation in many types of tumors, as well as immune diseases. By establishing a STAT3 signal based high-throughput drug screening system in human lung cancer A549 cells, we have screened a library from natural products which contained purified compounds from medicinal herbs. One compound, named Brevilin A, exhibited both strong STAT3 signal inhibition and STAT3 signal dependent cell growth inhibition. Further investigations revealed that Brevilin A not only inhibits STAT3 signaling but also STAT1 signaling for cytokines induced phosphorylation of STAT3 and STAT1 as well as the expression of their target genes. In addition, we found Brevilin A could attenuate the JAKs activity by blocking the JAKs tyrosine kinase domain JH1. The levels of cytokine induced phosphorylation of STATs and other substrates were dramatically reduced by treatment of Brevilin A. The roles of Brevilin A targeting on JAKs activity indicate that Brevilin A may not only be used as a STAT3 inhibitor but also a compound blocking other JAK-STAT hyperactivation. Thus, these findings provided a strong impetus for the development of selective JAK-STAT inhibitors and therapeutic drugs in order to improve survival of patients with hyperactivated JAKs and STATs.

  17. MEK/ERK signaling pathway in apoptosis of SW620 cell line and inhibition effect of resveratrol

    Institute of Scientific and Technical Information of China (English)

    Hao Chen; Zhi-Liang Jin; Hai Xu

    2016-01-01

    Objective: To study the involvement of MAPK MEK/ERK signaling transduction pathway in the apoptosis process of SW620 tumor cell line and the inhibition effect of resveratrol. Methods: SW620 cell lines were divided into 5 groups, namely, control group, PD98059 group, low-dose resveratrol group, mid-dose resveratrol group and high-dose resveratrol group. The inhibition rate of cell proliferation was detected by MTT method. The expression of apoptotic molecules and MEK/ERK signaling pathway related proteins were assayed by real-time PCR and Western blotting. Results: Compared with control group, the proliferation of cells treated with resveratrol was significantly inhibited. In the case of apoptotic molecules, the expression of Bax, Caspase 3 and Caspase 9 was increased significantly while the expression of anti-apoptotic molecule Bcl2 was decreased significantly in resveratrol groups with a dose-dependent manner. In the case of molecules in MEK/ERK signaling pathway, the expression of Ras, Raf, MEK and ERK1/2 was decreased significantly in resveratrol groups with a dose-dependent manner. Conclusions: PD98059 and resveratrol can effectively inhibit the proliferation of SW620 through inhibiting the MEK/ERK signaling pathway.

  18. Targeting Notch1 inhibits invasion and angiogenesis of human breast cancer cells via inhibition Nuclear Factor-κB signaling.

    Science.gov (United States)

    Liu, Yuan; Su, Chuanfu; Shan, Yuqing; Yang, Shouxiang; Ma, Guifeng

    2016-01-01

    Notch-1, a type-1 transmembrane protein, plays critical roles in the pathogenesis and progression of human malignancies, including breast cancer; however, the precise mechanism by which Notch-1 causes tumor cell invasion and angiogenesis remain unclear. Nuclear factor-κB (NF-κB), interleukin-8 (IL-8), vascular endothelial growth factor (VEGF), and matrix metalloproteinases (MMP) are critically involved in the processes of tumor cell invasion and metastasis, we investigated whether targeting Notch-1 could be mechanistically associated with the down-regulation of NF-κB, IL-8, VEGF, and MMP-9, resulting in the inhibition of invasion and angiogenesis of breast cancer cells. Our data showed that down-regulation of Notch-1 leads to the inactivation of NF-κB activity and inhibits the expression of its target genes, such as IL-8, VEGF and MMP-9. We also found that down-regulation of Notch-1 decreased cell invasion, and vice versa Consistent with these results, we also found that the down-regulation of Notch-1 not only decreased MMP-9 mRNA and its protein expression but also inhibited MMP-9 active form. Moreover, conditioned medium from Notch-1 siRNA-transfected breast cancer cells showed reduced levels of IL-8 and VEGF and, in turn, inhibited the tube formation of HUVECs, suggesting that down-regulation of Notch-1 leads to the inhibition of angiogenesis. Furthermore, conditioned medium from Notch-1 cDNA-transfected breast cancer cells showed increased levels of IL-8 and VEGF and, in turn, promoted the tube formation of HUVECs, suggesting that Notch-1 overexpression leads to the promotion of angiogenesis.We therefore concluded that down-regulation of Notch-1 leads to the inactivation NF-κB and its target genes (IL-8, MMP-9 and VEGF), resulting in the inhibition of invasion and angiogenesis.

  19. Withaferin A inhibits activation of signal transducer and activator of transcription 3 in human breast cancer cells

    OpenAIRE

    Lee, Joomin; Hahm, Eun-Ryeong; Singh, Shivendra V

    2010-01-01

    We have shown previously that withaferin A (WA), a promising anticancer constituent of Ayurvedic medicine plant Withania somnifera, inhibits growth of human breast cancer cells in culture and in vivo in association with apoptosis induction. The present study builds on these observations and demonstrates that WA inhibits constitutive as well as interleukin-6 (IL-6)-inducible activation of signal transducer and activator of transcription 3 (STAT3), which is an oncogenic transcription factor act...

  20. Inhibition of Histone Deacetylases Potentiates BMP9-Induced Osteogenic Signaling in Mouse Mesenchymal Stem Cells

    Directory of Open Access Journals (Sweden)

    Ning Hu

    2013-08-01

    Full Text Available Background/Aims: We have demonstrated that bone morphogenetic protein 9 (BMP9 is one of the most potent BMPs in regulating osteoblast differentiation of mesenchymal stem cells (MSCs although the molecular mechanism underlying BMP9-induced osteogenesis remains to be fully elucidated. It is known that epigenetic regulations play an important role in regulating the stem cell potency and lineage commitment. Here, we investigate if the inhibition of histone deacetylases (Hdacs affects BMP9-induced osteogenic differentiation of MSCs. Methods: Using the Hdac inhibitor trichostatin A (TSA, we assess that TSA enhances BMP9-mediated osteogenic markers and matrix mineralization in MSCs, and bone formation in mouse embryonic limb explants. Results: We find that the endogenous expression of most of the 11 Hdacs is readily detectable in MSCs. BMP9 is shown to induce most Hdacs in MSCs. We demonstrate that TSA potentiates BMP9-induced early osteogenic marker alkaline phosphatase (ALP activity in MSCs, as well as late osteogenic markers osteopontin (OPN and osteocalcin (OCN and matrix mineralization. Fetal limb explant culture studies reveal that TSA potentiates BMP9-induced endochondral bone formation, possibly by expanding hypertrophic chondrocyte zone of growth plate. Conclusion: Our findings strongly suggest histone deacetylases may play an important role in fine-tuning BMP9-mediated osteogenic signaling through a negative feedback network in MSCs. Thus, Hdac inhibitors may be used as novel therapeutics for bone fracture healing.

  1. Inhibition of host extracellular signal-regulated kinase (ERK) activation decreases new world alphavirus multiplication in infected cells

    Energy Technology Data Exchange (ETDEWEB)

    Voss, Kelsey; Amaya, Moushimi [National Center for Biodefense and Infectious Diseases, School of Systems Biology, George Mason University, 10650 Pyramid Place, Manassas, VA (United States); Mueller, Claudius [Center for Applied Proteomics and Personalized Medicine, George Mason University, 10900 University Boulevard, Manassas, VA (United States); Roberts, Brian [Leidos Health Life Sciences, 5202 Presidents Court, Suite 110, Frederick, MD (United States); Kehn-Hall, Kylene; Bailey, Charles [National Center for Biodefense and Infectious Diseases, School of Systems Biology, George Mason University, 10650 Pyramid Place, Manassas, VA (United States); Petricoin, Emanuel [Center for Applied Proteomics and Personalized Medicine, George Mason University, 10900 University Boulevard, Manassas, VA (United States); Narayanan, Aarthi, E-mail: anaraya1@gmu.edu [National Center for Biodefense and Infectious Diseases, School of Systems Biology, George Mason University, 10650 Pyramid Place, Manassas, VA (United States)

    2014-11-15

    New World alphaviruses belonging to the family Togaviridae are classified as emerging infectious agents and Category B select agents. Our study is focused on the role of the host extracellular signal-regulated kinase (ERK) in the infectious process of New World alphaviruses. Infection of human cells by Venezuelan equine encephalitis virus (VEEV) results in the activation of the ERK-signaling cascade. Inhibition of ERK1/2 by the small molecule inhibitor Ag-126 results in inhibition of viral multiplication. Ag-126-mediated inhibition of VEEV was due to potential effects on early and late stages of the infectious process. While expression of viral proteins was down-regulated in Ag-126 treated cells, we did not observe any influence of Ag-126 on the nuclear distribution of capsid. Finally, Ag-126 exerted a broad-spectrum inhibitory effect on New World alphavirus multiplication, thus indicating that the host kinase, ERK, is a broad-spectrum candidate for development of novel therapeutics against New World alphaviruses. - Highlights: • VEEV infection activated multiple components of the ERK signaling cascade. • Inhibition of ERK activation using Ag-126 inhibited VEEV multiplication. • Activation of ERK by Ceramide C6 increased infectious titers of TC-83. • Ag-126 inhibited virulent strains of all New World alphaviruses. • Ag-126 treatment increased percent survival of infected cells.

  2. Derivation of mesenchymal stromal cells from canine induced pluripotent stem cells by inhibition of the TGFβ/activin signaling pathway.

    Science.gov (United States)

    Whitworth, Deanne J; Frith, Jessica E; Frith, Thomas J R; Ovchinnikov, Dmitry A; Cooper-White, Justin J; Wolvetang, Ernst J

    2014-12-15

    In this study we have generated canine mesenchymal stromal cells (MSCs), also known as mesenchymal stem cells, from canine induced pluripotent stem cells (ciPSCs) by small-molecule inhibition of the transforming growth factor beta (TGFβ)/activin signaling pathway. These ciPSC-derived MSCs (ciPSC-MSCs) express the MSC markers CD73, CD90, CD105, STRO1, cPDGFRβ and cKDR, in addition to the pluripotency factors OCT4, NANOG and REX1. ciPSC-MSCs lack immunostaining for H3K27me3, suggesting that they possess two active X chromosomes. ciPSC-MSCs are highly proliferative and undergo robust differentiation along the osteo-, chondro- and adipogenic pathways, but do not form teratoma-like tissues in vitro. Of further significance for the translational potential of ciPSC-MSCs, we show that these cells can be encapsulated and maintained within injectable hydrogel matrices that, when functionalized with bound pentosan polysulfate, dramatically enhance chondrogenesis and inhibit osteogenesis. The ability to efficiently derive large numbers of highly proliferative canine MSCs from ciPSCs that can be incorporated into injectable, functionalized hydrogels that enhance their differentiation along a desired lineage constitutes an important milestone towards developing an effective MSC-based therapy for osteoarthritis in dogs, but equally provides a model system for assessing the efficacy and safety of analogous approaches for treating human degenerative joint diseases. PMID:25055193

  3. Norcantharidin inhibits Wnt signal pathway via promoter demethylation of WIF-1 in human non-small cell lung cancer.

    Science.gov (United States)

    Xie, Junran; Zhang, Yaping; Hu, Xuming; Lv, Ran; Xiao, Dongju; Jiang, Li; Bao, Qi

    2015-05-01

    Wingless-type (Wnt) family of secreted glycoproteins is a group of signal molecules implicated in oncogenesis. Abnormal activation of Wnt signal pathway is associated with a variety of human cancers, including non-small cell lung cancer (NSCLC). Wnt antagonists, such as the secreted frizzled-related protein (SFRP) family, Wnt inhibitory factor-1 (WIF-1) and cerberus, inhibit Wnt signal pathway by directly binding to Wnt molecules. Norcantharidin (NCTD) is known to possess anticancer activity but less nephrotoxicity than cantharidin. In this study, we found that NCTD inhibited cell proliferation, induced apoptosis, arrested cell cycle and suppressed cell invasion/migration in vitro. Additionally, Wnt signal pathway transcription was also suppressed. NCTD treatment blocked cytoplasmic translocation of beta-catenin into the nucleus. Alterations of apoptosis-related proteins, such as Bax, cleaved caspase-3 (pro-apoptotic) and Bcl-2 (anti-apoptotic), had been detected. Furthermore, the expression levels of WIF-1 and SFRP1 were significantly increased in NCTD-treated groups compared with negative control (NC) groups. Abnormal methylation was observed in NC groups, while NCTD treatment promoted WIF-1 demethylation. The present study revealed that NCTD activated WIF-1 via promoter demethylation, inhibiting the canonical Wnt signal pathway in NSCLC, which may present a new therapeutic target in vivo. PMID:25814287

  4. Growth inhibition and apoptosis in cancer cells induced by polyphenolic compounds of Acacia hydaspica: Involvement of multiple signal transduction pathways

    Science.gov (United States)

    Afsar, Tayyaba; Trembley, Janeen H.; Salomon, Christine E.; Razak, Suhail; Khan, Muhammad Rashid; Ahmed, Khalil

    2016-01-01

    Acacia hydaspica R. Parker is known for its medicinal uses in multiple ailments. In this study, we performed bioassay-guided fractionation of cytotoxic compounds from A. hydaspica and investigated their effects on growth and signaling activity in prostate and breast cancer cell lines. Four active polyphenolic compounds were identified as 7-O-galloyl catechin (GC), catechin (C), methyl gallate (MG), and catechin-3-O-gallate (CG). The four compounds inhibited prostate cancer PC-3 cell growth in a dose-dependent manner, whereas CG and MG inhibited breast cancer MDA-MB-231 cell growth. All tested compounds inhibited cell survival and colony growth in both cell lines, and there was evidence of chromatin condensation, cell shrinkage and apoptotic bodies. Further, acridine orange, ethidium bromide, propidium iodide and DAPI staining demonstrated that cell death occurred partly via apoptosis in both PC-3 and MDA-MB-231 cells. In PC-3 cells treatment repressed the expression of anti-apoptotic molecules Bcl-2, Bcl-xL and survivin, coupled with down-regulation of signaling pathways AKT, NFκB, ERK1/2 and JAK/STAT. In MDA-MB-231 cells, treatment induced reduction of CK2α, Bcl-xL, survivin and xIAP protein expression along with suppression of NFκB, JAK/STAT and PI3K pathways. Our findings suggest that certain polyphenolic compounds derived from A. hydaspica may be promising chemopreventive/therapeutic candidates against cancer. PMID:26975752

  5. 1-o-acetylbritannilactone (ABL) inhibits angiogenesis and lung cancer cell growth through regulating VEGF-Src-FAK signaling

    Energy Technology Data Exchange (ETDEWEB)

    Zhengfu, He; Hu, Zhang; Huiwen, Miao; Zhijun, Li [Department of Thoracic Surgery, Sir Run Run Shaw Hospital of Zhejiang University School of Medicine, Hangzhou (China); Jiaojie, Zhou [Zhejiang University School of Medicine, Hangzhou (China); Xiaoyi, Yan, E-mail: xiaoyiyan163@163.com [Zhejiang University School of Medicine, Hangzhou (China); Xiujun, Cai, E-mail: xiujuncaomaj@163.com [Sir Run Run Shaw Hospital of Zhejiang University School of Medicine, Hangzhou (China)

    2015-08-21

    The search for safe, effective and affordable therapeutics against non-small cell lung cancer (NSCLC) and other lung cancers is important. Here we explored the potential effect of 1-o-acetylbritannilactone (ABL), a novel extract from Inula britannica-F, on angiogenesis and lung cancer cell growth. We demonstrated that ABL dose-dependently inhibited vascular endothelial growth factor (VEGF)-induced proliferation, migration, and capillary structure formation of cultured human umbilical vascular endothelial cells (HUVECs). In vivo, ABL administration suppressed VEGF-induced new vasculature formation in Matrigel plugs. For the mechanism investigations, we found that ABL largely inhibited VEGF-mediated activation of Src kinase and focal adhesion kinase (FAK) in HUVECs. Furthermore, treatment of A549 NSCLC cells with ABL resulted in cell growth inhibition and Src-FAK in-activation. Significantly, administration of a single dose of ABL (12 mg/kg/day) remarkably suppressed growth of A549 xenografts in nude mice. In vivo microvessels formation and Src activation were also significantly inhibited in ABL-treated xenograft tumors. Taken together, our findings suggest that ABL suppresses angiogenesis and lung cancer cell growth possibly via regulating the VEGFR-Src-FAK signaling. - Highlights: • 1-o-acetylbritannilactone (ABL) inhibits VEGF-induced angiogenesis in vivo. • ABL inhibits VEGF-induced HUVEC migration, proliferation, capillary tube formation. • ABL inhibits VEGF-mediated activation of Src and FAK in HUVECs. • ABL inhibits growth and Src-FAK activation in A549 cells. • ABL administration inhibits A549 tumor angiogenesis and growth in nude mice.

  6. 1-o-acetylbritannilactone (ABL) inhibits angiogenesis and lung cancer cell growth through regulating VEGF-Src-FAK signaling

    International Nuclear Information System (INIS)

    The search for safe, effective and affordable therapeutics against non-small cell lung cancer (NSCLC) and other lung cancers is important. Here we explored the potential effect of 1-o-acetylbritannilactone (ABL), a novel extract from Inula britannica-F, on angiogenesis and lung cancer cell growth. We demonstrated that ABL dose-dependently inhibited vascular endothelial growth factor (VEGF)-induced proliferation, migration, and capillary structure formation of cultured human umbilical vascular endothelial cells (HUVECs). In vivo, ABL administration suppressed VEGF-induced new vasculature formation in Matrigel plugs. For the mechanism investigations, we found that ABL largely inhibited VEGF-mediated activation of Src kinase and focal adhesion kinase (FAK) in HUVECs. Furthermore, treatment of A549 NSCLC cells with ABL resulted in cell growth inhibition and Src-FAK in-activation. Significantly, administration of a single dose of ABL (12 mg/kg/day) remarkably suppressed growth of A549 xenografts in nude mice. In vivo microvessels formation and Src activation were also significantly inhibited in ABL-treated xenograft tumors. Taken together, our findings suggest that ABL suppresses angiogenesis and lung cancer cell growth possibly via regulating the VEGFR-Src-FAK signaling. - Highlights: • 1-o-acetylbritannilactone (ABL) inhibits VEGF-induced angiogenesis in vivo. • ABL inhibits VEGF-induced HUVEC migration, proliferation, capillary tube formation. • ABL inhibits VEGF-mediated activation of Src and FAK in HUVECs. • ABL inhibits growth and Src-FAK activation in A549 cells. • ABL administration inhibits A549 tumor angiogenesis and growth in nude mice

  7. Piperlongumine promotes autophagy via inhibition of Akt/mTOR signalling and mediates cancer cell death

    OpenAIRE

    Makhov, P; Golovine, K.; Teper, E.; Kutikov, A.; Mehrazin, R.; Corcoran, A; A. Tulin; Uzzo, R G; Kolenko, V M

    2014-01-01

    Background: The Akt/mammalian target of rapamycin (mTOR) signalling pathway serves as a critical regulator of cellular growth, proliferation and survival. Akt aberrant activation has been implicated in carcinogenesis and anticancer therapy resistance. Piperlongumine (PL), a natural alkaloid present in the fruit of the Long pepper, is known to exhibit notable anticancer effects. Here we investigate the impact of PL on Akt/mTOR signalling. Methods: We examined Akt/mTOR signalling in cancer cell...

  8. AM404 inhibits NFAT and NF-κB signaling pathways and impairs migration and invasiveness of neuroblastoma cells.

    Science.gov (United States)

    Caballero, Francisco J; Soler-Torronteras, Rafael; Lara-Chica, Maribel; García, Victor; Fiebich, Bernd L; Muñoz, Eduardo; Calzado, Marco A

    2015-01-01

    N-Arachidonoylphenolamine (AM404), a paracetamol lipid metabolite, is a modulator of the endocannabinoid system endowed with pleiotropic activities. AM404 is a dual agonist of the Transient Receptor Potential Vanilloid type 1 (TRPV1) and the Cannabinoid Receptor type 1 (CB₁) and inhibits anandamide (AEA) transport and degradation. In addition, it has been shown that AM404 also exerts biological activities through TRPV1- and CB₁ -independent pathways. In the present study we have investigated the effect of AM404 in the NFAT and NF-κB signaling pathways in SK-N-SH neuroblastoma cells. AM404 inhibited NFAT transcriptional activity through a CB₁- and TRPV1-independent mechanism. Moreover, AM404 inhibited both the expression of COX-2 at transcriptional and post-transcriptional levels and the synthesis of PGE₂. AM404 also inhibited NF-κB activation induced by PMA/Ionomycin in SK-N-SH cells by targeting IKKβ phosphorylation and activation. We found that Cot/Tlp-2 induced NFAT and COX-2 transcriptional activities were inhibited by AM404. NFAT inhibition paralleled with the ability of AM404 to inhibit MMP-1, -3 and -7 expression, cell migration and invasion in a cell-type specific dependent manner. Taken together, these data reveal that paracetamol, the precursor of AM404, can be explored not only as an antipyretic and painkiller drug but also as a co-adjuvant therapy in inflammatory and cancer diseases.

  9. Salt stress response triggers activation of the jasmonate signaling pathway leading to inhibition of cell elongation in Arabidopsis primary root.

    Science.gov (United States)

    Valenzuela, Camilo E; Acevedo-Acevedo, Orlando; Miranda, Giovanna S; Vergara-Barros, Pablo; Holuigue, Loreto; Figueroa, Carlos R; Figueroa, Pablo M

    2016-07-01

    Salinity is a severe abiotic stress that affects irrigated croplands. Jasmonate (JA) is an essential hormone involved in plant defense against herbivory and in responses to abiotic stress. However, the relationship between the salt stress response and the JA pathway in Arabidopsis thaliana is not well understood at molecular and cellular levels. In this work we investigated the activation of JA signaling by NaCl and its effect on primary root growth. We found that JA-responsive JAZ genes were up-regulated by salt stress in a COI1-dependent manner in the roots. Using a JA-Ile sensor we demonstrated that activation of JA signaling by salt stress occurs in the meristematic zone and stele of the differentiation zone and that this activation was dependent on JAR1 and proteasome functions. Another finding is that the elongation zone (EZ) and its cortical cells were significantly longer in JA-related mutants (AOS, COI1, JAZ3 and MYC2/3/4 genes) compared with wild-type plants under salt stress, revealing the participation of the canonical JA signaling pathway. Noteworthy, osmotic stress - a component of salt stress - inhibited cell elongation in the EZ in a COI1-dependent manner. We propose that salt stress triggers activation of the JA signaling pathway followed by inhibition of cell elongation in the EZ. We have shown that salt-inhibited root growth partially involves the jasmonate signaling pathway in Arabidopsis. PMID:27217545

  10. Cross talk Initiated by Endothelial Cells Enhances Migration and Inhibits Anoikis of Squamous Cell Carcinoma Cells through STAT3/Akt/ERK Signaling

    Directory of Open Access Journals (Sweden)

    Kathleen G. Neiva

    2009-06-01

    Full Text Available It is well known that cancer cells secrete angiogenic factors to recruit and sustain tumor vascular networks. However, little is known about the effect of endothelial cell-secreted factors on the phenotype and behavior of tumor cells. The hypothesis underlying this study is that endothelial cells initiate signaling pathways that enhance tumor cell survival and migration. Here, we observed that soluble mediators from primary human dermal microvascular endothelial cells induce phosphorylation of signal transducer and activator of transcription 3 (STAT3, Akt, and extracellular signal-regulated kinase (ERK in a panel of head and neck squamous cell carcinoma (HNSCC cells (OSCC-3, UM-SCC-1, UM-SCC-17B, UM-SCC-74A. Gene expression analysis demonstrated that interleukin-6 (IL- 6, interleukin-8 (CXCL8, and epidermal growth factor (EGF are upregulated in endothelial cells cocultured with HNSCC. Blockade of endothelial cell-derived IL-6, CXCL8, or EGF by gene silencing or neutralizing antibodies inhibited phosphorylation of STAT3, Akt, and ERK in tumor cells, respectively. Notably, activation of STAT3, Akt, and ERK by endothelial cells enhanced migration and inhibited anoikis of tumor cells. We have previously demonstrated that Bcl-2 is upregulated in tumor microvessels in patients with HNSCC. Here, we observed that Bcl-2 signaling induces expression of IL-6, CXCL8, and EGF, providing a mechanism for the upregulation of these cytokines in tumor-associated endothelial cells. This study expands the contribution of endothelial cells to the pathobiology of tumor cells. It unveils a new mechanism in which endothelial cells function as initiators of molecular crosstalks that enhance survival and migration of tumor cells.

  11. Sevoflurane inhibits the self-renewal of mouse embryonic stem cells via the GABAAR-ERK signaling pathway.

    Science.gov (United States)

    Yang, Liuqing; Ge, Yali; Lin, Shunyan; Fang, Xiangzhi; Zhou, Loujing; Gao, Ju

    2016-09-01

    A large number of pregnant women are exposed to inhalation anesthetics for non‑obstetric surgery. Previous studies have demonstrated the toxicity to the developing fetus caused by the inhalation anesthetic sevoflurane, which can permeate rapidly through the placental barrier. However, the mechanism of embryotoxicity remains largely unknown. The present study used mouse embryonic stem cells (mES cells) as an early development model, in order to investigate the mechanism underlying the embryo toxicity of sevoflurane and found that sevoflurane inhibited the self‑renewal of mES cells. Sevoflurane was shown to upregulate the level of phosphorylated extracellular signal‑regulated kinase (p‑ERK) but it did not affect the total expression of ERK by γ-aminobutyric acid A receptor (GABAAR). Knockdown of the GABAAR rescued the upregulation of p‑ERK and inhibition of self‑renewal induced by sevoflurane in mES cells. Additionally, inhibition of the activity of ERK signaling can rescue the influence of sevoflurane on mES cells. In conclusion, sevoflurane inhibited the self‑renewal of mES cells by GABAAR/ERK signaling, which may be a potential therapeutic target to prevent the embryotoxicity of sevoflurane. PMID:27431564

  12. UVB-induced cell death signaling is associated with G1-S progression and transcription inhibition in primary human fibroblasts.

    Directory of Open Access Journals (Sweden)

    Tatiana Grohmann Ortolan

    Full Text Available DNA damage induced by ultraviolet (UV radiation can be removed by nucleotide excision repair through two sub-pathways, one general (GGR and the other specific for transcribed DNA (TCR, and the processing of unrepaired lesions trigger signals that may lead to cell death. These signals involve the tumor suppressor p53 protein, a central regulator of cell responses to DNA damage, and the E3 ubiquitin ligase Mdm2, that forms a feedback regulatory loop with p53. The involvement of cell cycle and transcription on the signaling to apoptosis was investigated in UVB-irradiated synchronized, DNA repair proficient, CS-B (TCR-deficient and XP-C (GGR-deficient primary human fibroblasts. Cells were irradiated in the G1 phase of the cell cycle, with two doses with equivalent levels of apoptosis (low and high, defined for each cell line. In the three cell lines, the low doses of UVB caused only a transient delay in progression to the S phase, whereas the high doses induced permanent cell cycle arrest. However, while accumulation of Mdm2 correlated well with the recovery from transcription inhibition at the low doses for normal and CS-B fibroblasts, for XP-C cells this protein was shown to be accumulated even at UVB doses that induced high levels of apoptosis. Thus, UVB-induced accumulation of Mdm2 is critical for counteracting p53 activation and apoptosis avoidance, but its effect is limited due to transcription inhibition. However, in the case of XP-C cells, an excess of unrepaired DNA damage would be sufficient to block S phase progression, which would signal to apoptosis, independent of Mdm2 accumulation. The data clearly discriminate DNA damage signals that lead to cell death, depending on the presence of UVB-induced DNA damage in replicating or transcribing regions.

  13. Decreased autocrine EGFR signaling in metastatic breast cancer cells inhibits tumor growth in bone and mammary fat pad.

    Science.gov (United States)

    Nickerson, Nicole K; Mohammad, Khalid S; Gilmore, Jennifer L; Crismore, Erin; Bruzzaniti, Angela; Guise, Theresa A; Foley, John

    2012-01-01

    Breast cancer metastasis to bone triggers a vicious cycle of tumor growth linked to osteolysis. Breast cancer cells and osteoblasts express the epidermal growth factor receptor (EGFR) and produce ErbB family ligands, suggesting participation of these growth factors in autocrine and paracrine signaling within the bone microenvironment. EGFR ligand expression was profiled in the bone metastatic MDA-MB-231 cells (MDA-231), and agonist-induced signaling was examined in both breast cancer and osteoblast-like cells. Both paracrine and autocrine EGFR signaling were inhibited with a neutralizing amphiregulin antibody, PAR34, whereas shRNA to the EGFR was used to specifically block autocrine signaling in MDA-231 cells. The impact of these was evaluated with proliferation, migration and gene expression assays. Breast cancer metastasis to bone was modeled in female athymic nude mice with intratibial inoculation of MDA-231 cells, and cancer cell-bone marrow co-cultures. EGFR knockdown, but not PAR34 treatment, decreased osteoclasts formed in vitro (p<0.01), reduced osteolytic lesion tumor volume (p<0.01), increased survivorship in vivo (p<0.001), and resulted in decreased MDA-231 growth in the fat pad (p<0.01). Fat pad shEGFR-MDA-231 tumors produced in nude mice had increased necrotic areas and decreased CD31-positive vasculature. shEGFR-MDA-231 cells also produced decreased levels of the proangiogenic molecules macrophage colony stimulating factor-1 (MCSF-1) and matrix metalloproteinase 9 (MMP9), both of which were decreased by EGFR inhibitors in a panel of EGFR-positive breast cancer cells. Thus, inhibiting autocrine EGFR signaling in breast cancer cells may provide a means for reducing paracrine factor production that facilitates microenvironment support in the bone and mammary gland. PMID:22276166

  14. Decreased autocrine EGFR signaling in metastatic breast cancer cells inhibits tumor growth in bone and mammary fat pad.

    Directory of Open Access Journals (Sweden)

    Nicole K Nickerson

    Full Text Available Breast cancer metastasis to bone triggers a vicious cycle of tumor growth linked to osteolysis. Breast cancer cells and osteoblasts express the epidermal growth factor receptor (EGFR and produce ErbB family ligands, suggesting participation of these growth factors in autocrine and paracrine signaling within the bone microenvironment. EGFR ligand expression was profiled in the bone metastatic MDA-MB-231 cells (MDA-231, and agonist-induced signaling was examined in both breast cancer and osteoblast-like cells. Both paracrine and autocrine EGFR signaling were inhibited with a neutralizing amphiregulin antibody, PAR34, whereas shRNA to the EGFR was used to specifically block autocrine signaling in MDA-231 cells. The impact of these was evaluated with proliferation, migration and gene expression assays. Breast cancer metastasis to bone was modeled in female athymic nude mice with intratibial inoculation of MDA-231 cells, and cancer cell-bone marrow co-cultures. EGFR knockdown, but not PAR34 treatment, decreased osteoclasts formed in vitro (p<0.01, reduced osteolytic lesion tumor volume (p<0.01, increased survivorship in vivo (p<0.001, and resulted in decreased MDA-231 growth in the fat pad (p<0.01. Fat pad shEGFR-MDA-231 tumors produced in nude mice had increased necrotic areas and decreased CD31-positive vasculature. shEGFR-MDA-231 cells also produced decreased levels of the proangiogenic molecules macrophage colony stimulating factor-1 (MCSF-1 and matrix metalloproteinase 9 (MMP9, both of which were decreased by EGFR inhibitors in a panel of EGFR-positive breast cancer cells. Thus, inhibiting autocrine EGFR signaling in breast cancer cells may provide a means for reducing paracrine factor production that facilitates microenvironment support in the bone and mammary gland.

  15. Keratinocyte Growth Inhibition through the Modification of Wnt Signaling by Androgen in Balding Dermal Papilla Cells

    OpenAIRE

    Kitagawa, Tomoko; Matsuda, Ken-ichi; Inui, Shigeki; Takenaka, Hideya; Katoh, Norito; Itami, Satoshi; Kishimoto, Saburo; Kawata, Mitsuhiro

    2009-01-01

    Context/Objective: Androgen induces androgenetic alopecia (AGA), which has a regressive effect on hair growth from the frontal region of the scalp. Conversely, Wnt proteins are known to positively affect mammalian hair growth. We hypothesized that androgen reduces hair growth via an interaction with the Wnt signaling system. The objective of this study was to investigate the effect of androgen on Wnt signaling in dermal papilla (DP) cells.

  16. Sonic hedgehog signaling inhibition provides opportunities for targeted therapy by sulforaphane in regulating pancreatic cancer stem cell self-renewal.

    Directory of Open Access Journals (Sweden)

    Mariana Rodova

    Full Text Available Dysregulation of the sonic hedgehog (Shh signaling pathway has been associated with cancer stem cells (CSC and implicated in the initiation of pancreatic cancer. Pancreatic CSCs are rare tumor cells characterized by their ability to self-renew, and are responsible for tumor recurrence accompanied by resistance to current therapies. The lethality of these incurable, aggressive and invasive pancreatic tumors remains a daunting clinical challenge. Thus, the objective of this study was to investigate the role of Shh pathway in pancreatic cancer and to examine the molecular mechanisms by which sulforaphane (SFN, an active compound in cruciferous vegetables, inhibits self-renewal capacity of human pancreatic CSCs. Interestingly, we demonstrate here that Shh pathway is highly activated in pancreatic CSCs and plays important role in maintaining stemness by regulating the expression of stemness genes. Given the requirement for Hedgehog in pancreatic cancer, we investigated whether hedgehog blockade by SFN could target the stem cell population in pancreatic cancer. In an in vitro model, human pancreatic CSCs derived spheres were significantly inhibited on treatment with SFN, suggesting the clonogenic depletion of the CSCs. Interestingly, SFN inhibited the components of Shh pathway and Gli transcriptional activity. Interference of Shh-Gli signaling significantly blocked SFN-induced inhibitory effects demonstrating the requirement of an active pathway for the growth of pancreatic CSCs. SFN also inhibited downstream targets of Gli transcription by suppressing the expression of pluripotency maintaining factors (Nanog and Oct-4 as well as PDGFRα and Cyclin D1. Furthermore, SFN induced apoptosis by inhibition of BCL-2 and activation of caspases. Our data reveal the essential role of Shh-Gli signaling in controlling the characteristics of pancreatic CSCs. We propose that pancreatic cancer preventative effects of SFN may result from inhibition of the Shh pathway

  17. Inhibition of de novo Palmitate Synthesis by Fatty Acid Synthase Induces Apoptosis in Tumor Cells by Remodeling Cell Membranes, Inhibiting Signaling Pathways, and Reprogramming Gene Expression

    Directory of Open Access Journals (Sweden)

    Richard Ventura

    2015-08-01

    Research in context: Fatty acid synthase (FASN is a vital enzyme in tumor cell biology; the over-expression of FASN is associated with diminished patient prognosis and resistance to many cancer therapies. Our data demonstrate that selective and potent FASN inhibition with TVB-3166 leads to selective death of tumor cells, without significant effect on normal cells, and inhibits in vivo xenograft tumor growth at well-tolerated doses. Candidate biomarkers for selecting tumors highly sensitive to FASN inhibition are identified. These preclinical data provide mechanistic and pharmacologic evidence that FASN inhibition presents a promising therapeutic strategy for treating a variety of cancers.

  18. A novel taspine derivative, HMQ1611, inhibits breast cancer cell growth via estrogen receptor α and EGF receptor signaling pathways.

    Science.gov (United States)

    Zhan, Yingzhuan; Zhang, Yanmin; Liu, Cuicui; Zhang, Jie; Smith, Wanli W; Wang, Nan; Chen, Yinnan; Zheng, Lei; He, Langchong

    2012-06-01

    Breast cancer is a common cancer with a leading cause of cancer mortality in women. Currently, the chemotherapy for breast cancer is underdeveloped. Here, we report a novel taspine derivative, HMQ1611, which has anticancer effects using in vitro and in vivo breast cancer models. HMQ1611 reduced cancer cell proliferation in four human breast cancer cell lines including MDA-MB-231, SK-BR-3, ZR-75-30, and MCF-7. HMQ1611 more potently reduced growth of estrogen receptor α (ERα)-positive breast cancer cells (ZR-75-30 and MCF-7) than ERα-negative cells (MDA-MB-231 and SK-BR-3). Moreover, HMQ1611 arrested breast cancer cell cycle at S-phase. In vivo tumor xenograft model, treatment of HMQ1611 significantly reduced tumor size and weight compared with vehicles. We also found that HMQ1611 reduced ERα expression and inhibited membrane ERα-mediated mitogen-activated protein kinase (MAPK) signaling following the stimulation of cells with estrogen. Knockdown of ERα by siRNA transfection in ZR-75-30 cells attenuated HMQ1611 effects. In contrast, overexpression of ERα in MDA-MB-231 cells enhanced HMQ1611 effects, suggesting that ERα pathway mediated HMQ1611's inhibition of breast cancer cell growth in ERα-positive breast cancer. HMQ1611 also reduced phosphorylation of EGF receptor (EGFR) and its downstream signaling players extracellular signal-regulated kinase (ERK)1/2 and AKT activation both in ZR-75-30 and MDA-MB-231 cells. These results showed that the novel compound HMQ1611 had anticancer effects, and partially via ERα and/or EGFR signaling pathways, suggesting that HMQ1611 may be a potential novel candidate for human breast cancer intervention.

  19. Inhibition of the integrin signal constitutes a mouse iPS cell niche.

    Science.gov (United States)

    Higuchi, Sayaka; Yoshina, Sawako; Mitani, Shohei

    2016-09-01

    Stem cells are regulated by their surrounding microenvironments, called niche, such as cell-cell interaction and extracellular matrix. Classically, feeder cells as a niche have been used in the culture of iPS cells from both the mouse and the human. However, the regulation mechanism of stem cells by feeder cells as a niche still have been partially unclear. In this study, we used three murine iPS cell lines, iPS-MEF-Ng-20D-17, iPS-MEF-Ng-178B-5 and iPS-MEF-Fb/Ng-440A-3, which were generated by different reprogramming methods. In general, these cell lines commonly need the feeder cells as a niche to culture. Recently, the effect of substrate stiffness is known in stem cell study. First, we focused on the mechanical properties of feeder cells, and then we speculated that feeder-less culture might be made possible by using molecules in place of the mechanical properties of the niche. Finally, we found that the combination of disintegrin (echistatin) and 2i (GSK3 inhibitor and MEK inhibitor) is a sufficient condition for three murine iPS culture. This novel method of mimicking the murine iPS cell niche may be useful to understand signaling pathways to maintain the pluripotency of stem cells. PMID:27633818

  20. IL-24 Inhibits Lung Cancer Cell Migration and Invasion by Disrupting The SDF-1/CXCR4 Signaling Axis

    OpenAIRE

    Panneerselvam, Janani; Jin, Jiankang; Shanker, Manish; Lauderdale, Jason; Bates, Jonathan; Wang, Qi; Zhao, Yan D.; Stephen J Archibald; Timothy J. Hubin; Ramesh, Rajagopal

    2015-01-01

    Background The stromal cell derived factor (SDF)-1/chemokine receptor (CXCR)-4 signaling pathway plays a key role in lung cancer metastasis and is molecular target for therapy. In the present study we investigated whether interleukin (IL)-24 can inhibit the SDF-1/CXCR4 axis and suppress lung cancer cell migration and invasion in vitro. Further, the efficacy of IL-24 in combination with CXCR4 antagonists was investigated. Methods Human H1299, A549, H460 and HCC827 lung cancer cell lines were u...

  1. Inhibition of Hedgehog-Signaling Driven Genes in Prostate Cancer Cells by Sutherlandia frutescens Extract

    OpenAIRE

    Yuan Lu; Nicholas Starkey; Wei Lei; Jilong Li; Jianlin Cheng; Folk, William R.; Lubahn, Dennis B.

    2015-01-01

    Sutherlandia frutescens (L) R. Br. (Sutherlandia) is a South African botanical that is traditionally used to treat a variety of health conditions, infections and diseases, including cancer. We hypothesized Sutherlandia might act through Gli/ Hedgehog (Hh)-signaling in prostate cancer cells and used RNA-Seq transcription profiling to profile gene expression in TRAMPC2 murine prostate cancer cells with or without Sutherlandia extracts. We found 50% of Hh-responsive genes can be repressed by Sut...

  2. Hinokitiol Inhibits Melanogenesis via AKT/mTOR Signaling in B16F10 Mouse Melanoma Cells.

    Science.gov (United States)

    Tsao, Yu-Tzu; Huang, Yu-Fen; Kuo, Chun-Yu; Lin, Yu-Chiang; Chiang, Wei-Cheng; Wang, Wei-Kuang; Hsu, Chia-Wei; Lee, Che-Hsin

    2016-01-01

    H inokitiol purified from the heartwood of cupressaceous plants has had various biological functions of cell differentiation and growth. Hinokitiol has been demonstrated as having an important role in anti-inflammation and anti-bacteria effect, suggesting that it is potentially useful in therapies for hyperpigmentation. Previously, hinokitiol inhibited the production of melanin by inhibiting tyrosinase activity. The autophagic signaling pathway can induce hypopigmentation. This study is warranted to investigate the mechanism of hinokitiol-induced hypopigmentation through autophagy in B16F10 melanoma cells. The melanin contents and expression of microthphalmia associated transcription factor (MITF) and tyrosinase were inhibited by treatment with hinokitiol. Moreover, the phosphorylation of the protein express levels of phospho-protein kinase B (P-AKT) and phospho-mammalian targets of rapamycin (P-mTOR) were reduced after hinokitiol treatment. In addition, the microtubule associated protein 1 light chain 3 (LC3) -II and beclin 1 (autophagic markers) were increased after the B16F10 cell was treated with hinokitiol. Meanwhile, hinokitiol decreased cellular melanin contents in a dose-dependent manner. These findings establish that hinokitiol inhibited melanogenesis through the AKT/mTOR signaling pathway. PMID:26901194

  3. Belinostat-induced apoptosis and growth inhibition in pancreatic cancer cells involve activation of TAK1-AMPK signaling axis

    International Nuclear Information System (INIS)

    Highlights: •Belinostat activates AMPK in cultured pancreatic cancer cells. •Activation of AMPK is important for belinostat-induced cytotoxic effects. •ROS and TAK1 are involved in belinostat-induced AMPK activation. •AMPK activation mediates mTOR inhibition by belinostat. -- Abstract: Pancreatic cancer accounts for more than 250,000 deaths worldwide each year. Recent studies have shown that belinostat, a novel pan histone deacetylases inhibitor (HDACi) induces apoptosis and growth inhibition in pancreatic cancer cells. However, the underlying mechanisms are not fully understood. In the current study, we found that AMP-activated protein kinase (AMPK) activation was required for belinostat-induced apoptosis and anti-proliferation in PANC-1 pancreatic cancer cells. A significant AMPK activation was induced by belinostat in PANC-1 cells. Inhibition of AMPK by RNAi knockdown or dominant negative (DN) mutation significantly inhibited belinostat-induced apoptosis in PANC-1 cells. Reversely, AMPK activator AICAR and A-769662 exerted strong cytotoxicity in PANC-1 cells. Belinostat promoted reactive oxygen species (ROS) production in PANC-1 cells, increased ROS induced transforming growth factor-β-activating kinase 1 (TAK1)/AMPK association to activate AMPK. Meanwhile, anti-oxidants N-Acetyl-Cysteine (NAC) and MnTBAP as well as TAK1 shRNA knockdown suppressed belinostat-induced AMPK activation and PANC-1 cell apoptosis. In conclusion, we propose that belinostat-induced apoptosis and growth inhibition require the activation of ROS-TAK1-AMPK signaling axis in cultured pancreatic cancer cells

  4. Cell-autonomous activation of Hedgehog signaling inhibits brown adipose tissue development

    Science.gov (United States)

    Although recent studies have shown that brown adipose tissue (BAT) arises from progenitor cells that also give rise to skeletal muscle, the developmental signals that control the formation of BAT remain largely unknown. Here, we show that brown preadipocytes possess primary cilia and can respond to ...

  5. Sunitinib induces PTEN expression and inhibits PDGFR signaling and migration of medulloblastoma cells

    OpenAIRE

    Abouantoun, Thamara J.; Castellino, Robert C.; MacDonald, Tobey J.

    2010-01-01

    We previously showed that inhibition of the platelet-derived growth factor receptor (PDGFR) blocks the survival and migration of medulloblastoma cells. Identification of in vitro PDGFR-targeting pharmacologic agents that are suitable for preclinical testing in medulloblastoma models in vivo will be critical for efficiently translating these agents to clinical investigation in children with medulloblastoma. In this study, we investigated whether the multi-tyrosine kinase inhibitor sunitinib, e...

  6. Inhibition of Notch signaling reduces the number of surviving Dclk1+ reserve crypt epithelial stem cells following radiation injury.

    Science.gov (United States)

    Qu, Dongfeng; May, Randal; Sureban, Sripathi M; Weygant, Nathaniel; Chandrakesan, Parthasarathy; Ali, Naushad; Li, Linheng; Barrett, Terrence; Houchen, Courtney W

    2014-03-01

    We have previously reported that doublecortin-like kinase 1 (Dclk1) is a putative intestinal stem cell (ISC) marker. In this report, we evaluated the use of Dclk1 as a marker of surviving ISCs in response to treatment with high-dose total body irradiation (TBI). Both apoptotic and mitotic Dclk1(+) cells were observed 24 h post-TBI associated with a corresponding loss of intestinal crypts observed at 84 h post-TBI. Although the Notch signaling pathway plays an important role in regulating proliferation and lineage commitment within the intestine, its role in ISC function in response to severe genotoxic injury is not yet fully understood. We employed the microcolony assay to functionally assess the effects of Notch inhibition with difluorophenacetyl-l-alanyl-S-phenylglycine t-butyl ester (DAPT) on intestinal crypt stem cell survival following severe (>8 Gy) radiation injury. Following treatment with DAPT, we observed a nearly 50% reduction in the number of surviving Dclk1(+) crypt epithelial cells at 24 h after TBI and similar reduction in the number of surviving small intestinal crypts at 84 h. These data indicate that inhibition of Notch signaling decreases ISC survival following radiation injury, suggesting that the Notch signaling pathway plays an important role in ISC-mediated crypt regeneration. These results also suggest that crypt epithelial cell Dclk1 expression can be used as one potential marker to evaluate the early survival of ISCs following severe radiation injury.

  7. VEGF Silencing Inhibits Human Osteosarcoma Angiogenesis and Promotes Cell Apoptosis via PI3K/AKT Signaling Pathway.

    Science.gov (United States)

    Zhao, Jian; Zhang, Zi-Ru; Zhao, Na; Ma, Bao-An; Fan, Qing-Yu

    2015-11-01

    Vascular endothelial growth factor (VEGF) is one of the most effective angiogenic factors that promote generation of tumor vasculature. VEGF is usually up-regulated in multiple cancers including osteosarcoma and glioma. To further explore the potential molecular mechanism that inhibits tumor growth induced by interference of VEGF expression, we constructed a Lv-shVEGF vector and assessed the efficiency of VEGF silencing and its influence in U2OS cells. The data demonstrate that Lv-shVEGF has high inhibition efficiency on VEGF expression, which inhibits proliferation and promotes apoptosis of U2OS cells in vitro. Our results also indicate that inhibition of VEGF expression suppresses osteosarcoma tumor growth in vivo and reduces osteosarcoma angiogenesis. We also found that the activations of phosphoinositide 3-kinase (PI3K) and protein kinase B (AKT) were considerably reduced after osteosarcoma cells were treated with Lv-shVEGF. Taken together, our data demonstrate that VEGF silencing suppresses cell proliferation, promotes cell apoptosis, and reduces osteosarcoma angiogenesis through inactivation of PI3K/AKT signaling pathway. PMID:27352347

  8. Valproate inhibits MAP kinase signalling and cell cycle progression in S. cerevisiae

    Science.gov (United States)

    Desfossés-Baron, Kristelle; Hammond-Martel, Ian; Simoneau, Antoine; Sellam, Adnane; Roberts, Stephen; Wurtele, Hugo

    2016-01-01

    The mechanism of action of valproate (VPA), a widely prescribed short chain fatty acid with anticonvulsant and anticancer properties, remains poorly understood. Here, the yeast Saccharomyces cerevisiae was used as model to investigate the biological consequences of VPA exposure. We found that low pH strongly potentiates VPA-induced growth inhibition. Transcriptional profiling revealed that under these conditions, VPA modulates the expression of genes involved in diverse cellular processes including protein folding, cell wall organisation, sexual reproduction, and cell cycle progression. We further investigated the impact of VPA on selected processes and found that this drug: i) activates markers of the unfolded protein stress response such as Hac1 mRNA splicing; ii) modulates the cell wall integrity pathway by inhibiting the activation of the Slt2 MAP kinase, and synergizes with cell wall stressors such as micafungin and calcofluor white in preventing yeast growth; iii) prevents activation of the Kss1 and Fus3 MAP kinases of the mating pheromone pathway, which in turn abolishes cellular responses to alpha factor; and iv) blocks cell cycle progression and DNA replication. Overall, our data identify heretofore unknown biological responses to VPA in budding yeast, and highlight the broad spectrum of cellular pathways influenced by this chemical in eukaryotes. PMID:27782169

  9. PI3K/Akt signaling mediated Hexokinase-2 expression inhibits cell apoptosis and promotes tumor growth in pediatric osteosarcoma

    Energy Technology Data Exchange (ETDEWEB)

    Zhuo, Baobiao; Li, Yuan; Li, Zhengwei; Qin, Haihui; Sun, Qingzeng; Zhang, Fengfei; Shen, Yang; Shi, Yingchun [Department of Surgery, The Children' s Hospital of Xuzhou, Xuzhou, Jiangsu Province 221006 (China); Wang, Rong, E-mail: wangrong2008163@163.com [Department of Ultrasonography, Affiliated Hospital of Xuzhou Medical College, Xuzhou, Jiangsu Province 221006 (China)

    2015-08-21

    Accumulating evidence has shown that PI3K/Akt pathway is frequently hyperactivated in osteosarcoma (OS) and contributes to tumor initiation and progression. Altered phenotype of glucose metabolism is a key hallmark of cancer cells including OS. However, the relationship between PI3K/Akt pathway and glucose metabolism in OS remains largely unexplored. In this study, we showed that elevated Hexokinase-2 (HK2) expression, which catalyzes the first essential step of glucose metabolism by conversion of glucose into glucose-6-phosphate, was induced by activated PI3K/Akt signaling. Immunohistochemical analysis showed that HK2 was overexpressed in 83.3% (25/30) specimens detected and was closely correlated with Ki67, a cell proliferation index. Silencing of endogenous HK2 resulted in decreased aerobic glycolysis as demonstrated by reduced glucose consumption and lactate production. Inhibition of PI3K/Akt signaling also suppressed aerobic glycolysis and this effect can be reversed by reintroduction of HK2. Furthermore, knockdown of HK2 led to increased cell apoptosis and reduced ability of colony formation; meanwhile, these effects were blocked by 2-Deoxy-D-glucose (2-DG), a glycolysis inhibitor through its actions on hexokinase, indicating that HK2 functions in cell apoptosis and growth were mediated by altered aerobic glycolysis. Taken together, our study reveals a novel relationship between PI3K/Akt signaling and aerobic glycolysis and indicates that PI3K/Akt/HK2 might be potential therapeutic approaches for OS. - Highlights: • PI3K/Akt signaling contributes to elevated expression of HK2 in osteosarcoma. • HK2 inhibits cell apoptosis and promotes tumor growth through enhanced Warburg effect. • Inhibition of glycolysis blocks the oncogenic activity of HK2.

  10. Silibinin inhibits fibronectin induced motility, invasiveness and survival in human prostate carcinoma PC3 cells via targeting integrin signaling

    Energy Technology Data Exchange (ETDEWEB)

    Deep, Gagan [Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado Denver, Aurora, CO (United States); University of Colorado Cancer Center, University of Colorado Denver, Aurora, CO (United States); Kumar, Rahul; Jain, Anil K. [Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado Denver, Aurora, CO (United States); Agarwal, Chapla [Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado Denver, Aurora, CO (United States); University of Colorado Cancer Center, University of Colorado Denver, Aurora, CO (United States); Agarwal, Rajesh, E-mail: Rajesh.agarwal@ucdenver.edu [Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado Denver, Aurora, CO (United States); University of Colorado Cancer Center, University of Colorado Denver, Aurora, CO (United States)

    2014-10-15

    Highlights: • Silibinin inhibits fibronectin-induce motile morphology in PC3 cells. • Silibinin inhibits fibronectin-induced migration and invasion in PC3 cells. • Silibinin targets fibronectin-induced integrins and downstream signaling molecule. - Abstract: Prostate cancer (PCA) is the 2nd leading cause of cancer-related deaths among men in the United States. Preventing or inhibiting metastasis-related events through non-toxic agents could be a useful approach for lowering high mortality among PCA patients. We have earlier reported that natural flavonoid silibinin possesses strong anti-metastatic efficacy against PCA however, mechanism/s of its action still remains largely unknown. One of the major events during metastasis is the replacement of cell–cell interaction with integrins-based cell–matrix interaction that controls motility, invasiveness and survival of cancer cells. Accordingly, here we examined silibinin effect on advanced human PCA PC3 cells’ interaction with extracellular matrix component fibronectin. Silibinin (50–200 μM) treatment significantly decreased the fibronectin (5 μg/ml)-induced motile morphology via targeting actin cytoskeleton organization in PC3 cells. Silibinin also decreased the fibronectin-induced cell proliferation and motility but significantly increased cell death in PC3 cells. Silibinin also inhibited the PC3 cells invasiveness in Transwell invasion assays with fibronectin or cancer associated fibroblasts (CAFs) serving as chemoattractant. Importantly, PC3-luc cells cultured on fibronectin showed rapid dissemination and localized in lungs following tail vein injection in athymic male nude mice; however, in silibinin-treated PC3-luc cells, dissemination and lung localization was largely compromised. Molecular analyses revealed that silibinin treatment modulated the fibronectin-induced expression of integrins (α5, αV, β1 and β3), actin-remodeling (FAK, Src, GTPases, ARP2 and cortactin), apoptosis (cPARP and

  11. Pharmacological inhibition of EGFR signaling enhances G-CSF-induced hematopoietic stem cell mobilization.

    Science.gov (United States)

    Ryan, Marnie A; Nattamai, Kalpana J; Xing, Ellen; Schleimer, David; Daria, Deidre; Sengupta, Amitava; Köhler, Anja; Liu, Wei; Gunzer, Matthias; Jansen, Michael; Ratner, Nancy; Le Cras, Timothy D; Waterstrat, Amanda; Van Zant, Gary; Cancelas, Jose A; Zheng, Yi; Geiger, Hartmut

    2010-10-01

    Mobilization of hematopoietic stem and progenitor cells (HSPCs) from bone marrow into peripheral blood by the cytokine granulocyte colony-stimulating factor (G-CSF) has become the preferred source of HSPCs for stem cell transplants. However, G-CSF fails to mobilize sufficient numbers of stem cells in up to 10% of donors, precluding autologous transplantation in those donors or substantially delaying transplant recovery time. Consequently, new regimens are needed to increase the number of stem cells in peripheral blood upon mobilization. Using a forward genetic approach in mice, we mapped the gene encoding the epidermal growth factor receptor (Egfr) to a genetic region modifying G-CSF-mediated HSPC mobilization. Amounts of EGFR in HSPCs inversely correlated with the cells' ability to be mobilized by G-CSF, implying a negative role for EGFR signaling in mobilization. In combination with G-CSF treatment, genetic reduction of EGFR activity in HSPCs (in waved-2 mutant mice) or treatment with the EGFR inhibitor erlotinib increased mobilization. Increased mobilization due to suppression of EGFR activity correlated with reduced activity of cell division control protein-42 (Cdc42), and genetic Cdc42 deficiency in vivo also enhanced G-CSF-induced mobilization. Our findings reveal a previously unknown signaling pathway regulating stem cell mobilization and provide a new pharmacological approach for improving HSPC mobilization and thereby transplantation outcomes. PMID:20871610

  12. Camptothecin inhibits platelet-derived growth factor-BB-induced proliferation of rat aortic vascular smooth muscle cells through inhibition of PI3K/Akt signaling pathway

    Energy Technology Data Exchange (ETDEWEB)

    Park, Eun-Seok [Department of Applied Biochemistry, Division of Life Science, College of Health and Biomedical Science, Konkuk University, Chungju, Chungbuk (Korea, Republic of); Kang, Shin-il [College of Pharmacy Medical Research Center, Chungbuk National University, Cheongju (Korea, Republic of); Yoo, Kyu-dong [Hazardous Substances Analysis Division, Gwangju Regional Food and Drug Administration, Gwangju (Korea, Republic of); Lee, Mi-Yea [Department of Nursing Kyungbok University, Pocheon (Korea, Republic of); Yoo, Hwan-Soo; Hong, Jin-Tae [College of Pharmacy Medical Research Center, Chungbuk National University, Cheongju (Korea, Republic of); Shin, Hwa-Sup [Department of Applied Biochemistry, Division of Life Science, College of Health and Biomedical Science, Konkuk University, Chungju, Chungbuk (Korea, Republic of); Kim, Bokyung [Department of Physiology, Konkuk Medical School, Konkuk University, Chungju, Chungbuk (Korea, Republic of); Yun, Yeo-Pyo, E-mail: ypyun@chungbuk.ac.kr [College of Pharmacy Medical Research Center, Chungbuk National University, Cheongju (Korea, Republic of)

    2013-04-15

    The abnormal proliferation of vascular smooth muscle cells (VSMCs) in arterial wall is a major cause of vascular disorders such as atherosclerosis and restenosis after angioplasty. In this study, we investigated not only the inhibitory effects of camptothecin (CPT) on PDGF-BB-induced VSMC proliferation, but also its molecular mechanism of this inhibition. CPT significantly inhibited proliferation with IC50 value of 0.58 μM and the DNA synthesis of PDGF-BB-stimulated VSMCs in a dose-dependent manner (0.5–2 μM ) without any cytotoxicity. CPT induced the cell cycle arrest at G0/G1 phase. Also, CPT decreased the expressions of G0/G1-specific regulatory proteins including cyclin-dependent kinase (CDK)2, cyclin D1 and PCNA in PDGF-BB-stimulated VSMCs. Pre-incubation of VSMCs with CPT significantly inhibited PDGF-BB-induced Akt activation, whereas CPT did not affect PDGF-receptor beta phosphorylation, extracellular signal-regulated kinase (ERK) 1/2 phosphorylation and phospholipase C (PLC)-γ1 phosphorylation in PDGF-BB signaling pathway. Our data showed that CPT pre-treatment inhibited VSMC proliferation, and that the inhibitory effect of CPT was enhanced by LY294002, a PI3K inhibitor, on PDGF-BB-induced VSMC proliferation. In addition, inhibiting the PI3K/Akt pathway by LY294002 significantly enhanced the suppression of PCNA expression and Akt activation by CPT. These results suggest that the anti-proliferative activity of CPT is mediated in part by downregulating the PI3K/Akt signaling pathway. - Highlights: ► CPT inhibits proliferation of PDGF-BB-induced VSMC without cytotoxicity. ► CPT arrests the cell cycle in G0/G1 phase by downregulation of cyclin D1 and CDK2. ► CPT significantly attenuates Akt phosphorylation in PDGF-BB signaling pathway. ► LY294002 enhanced the inhibitory effect of CPT on VSMC proliferation. ► Thus, CPT is mediated by downregulating the PI3K/Akt signaling pathway.

  13. Resveratrol inhibits lipogenesis of 3T3-L1 and SGBS cells by inhibition of insulin signaling and mitochondrial mass increase.

    Science.gov (United States)

    Li, Shuijie; Bouzar, Célia; Cottet-Rousselle, Cécile; Zagotta, Ivana; Lamarche, Frédéric; Wabitsch, Martin; Tokarska-Schlattner, Malgorzata; Fischer-Posovszky, Pamela; Schlattner, Uwe; Rousseau, Denis

    2016-06-01

    Resveratrol is attracting much interest because of its potential to decrease body weight and increase life span, influencing liver and muscle function by increasing mitochondrial mass and energy expenditure. Even though resveratrol was already shown to reduce the adipose tissue mass in animal models, its effects on mitochondrial mass and network structure in adipocytes have not yet been studied. For this purpose, we investigated the effect of resveratrol on mitochondrial mass increase and remodeling during adipogenic differentiation of two in vitro models of adipocyte biology, the murine 3T3-L1 cell line and the human SGBS cell strain. We confirm that resveratrol inhibits lipogenesis in differentiating adipocytes, both mouse and human. We further show that this is linked to inhibition of the normally observed mitochondrial mass increase and mitochondrial remodeling. At the molecular level, the anti-lipogenic effect of resveratrol seems to be mediated by a blunted expression increase and an inhibition of acetyl-CoA carboxylase (ACC). This is one of the consequences of an inhibited insulin-induced signaling via Akt, and maintained signaling via AMP-activated protein kinase. The anti-lipogenic effect of resveratrol is further modulated by expression levels of mitochondrial ATAD3, consistent with the emerging role of this protein as an important regulator of mitochondrial biogenesis and lipogenesis. Our data suggest that resveratrol acts on differentiating preadipocytes by inhibiting insulin signaling, mitochondrial biogenesis, and lipogenesis, and that resveratrol-induced reduction of mitochondrial biogenesis and lipid storage contribute to adipose tissue weight loss in animals and humans.

  14. All-Trans Retinoic Acid Inhibits Human Colorectal Cancer Cells RKO Migration via Downregulating Myosin Light Chain Kinase Expression through MAPK Signaling Pathway.

    Science.gov (United States)

    Zuo, Li; Yang, Xiaoping; Lu, Man; Hu, Ruolei; Zhu, Huaqing; Zhang, Sumei; Zhou, Qing; Chen, Feihu; Gui, Shuyu; Wang, Yuan

    2016-10-01

    All-trans-retinoic acid (ATRA) inhibits the invasive and metastatic potentials of various cancer cells. However, the underlying mechanism is unclear. Here, we demonstrate that ATRA inhibited colorectal cancer cells RKO (human colon adenocarcinoma cell) migration by downregulating cell movement and increasing cell adhesion. ATRA inhibited the expression and activation of myosin light chain kinase (MLCK) in RKO cells, while the expression level of MLC phosphatase (MLCP) had no change in RKO cells treated with or without ATRA. The expression and activity of MLC was also inhibited in RKO cells exposed to ATRA. Intriguingly, ATRA increased the expression of occludin messenger RNA (mRNA) and protein and its localization on cell membrane. However, ATRA did not change the expression of zonula occludens 1 (ZO-1), but increased the accumulation of ZO-1 on RKO cells membrane. ML-7, an inhibitor of MLCK, significantly inhibited RKO cell migration. Furthermore, knockdown of endogenous MLCK expression inhibited RKO migration. Mechanistically, we showed that MAPK-specific inhibitor PD98059 enhanced the inhibitory effect of ATRA on RKO migration. In contrast, phorbol 12-myristate 13-acetate (PMA) attenuated the effects of ATRA in RKO cells. Moreover, knocking down endogenous extracellular signal-regulated kinase (ERK) expression inhibited MLCK expression in the RKO cells. In conclusion, ATRA inhibits RKO migration by reducing MLCK expression via extracellular signal-regulated kinase 1/Mitogen-activated protein kinase (ERK1/MAPK) signaling pathway. PMID:27564600

  15. Inhibition of Notch signaling affects hepatic oval cell response in rat model of 2AAF-PH

    Directory of Open Access Journals (Sweden)

    Darwiche H

    2011-09-01

    Full Text Available Houda Darwiche, Seh-Hoon Oh, Nicole C Steiger-Luther, Jennifer M Williams, Dana G Pintilie, Thomas D Shupe, Bryon E PetersenDepartment of Pathology, Immunology, and Laboratory Medicine, Program in Stem Cell Biology and Regenerative Medicine, College of Medicine, University of Florida, Gainesville, FL, USABackground and aims: Activation of the oval cell compartment occurs in the liver when hepatocytes are functionally compromised and/or unable to divide. Our goal was to investigate the systemic signals responsible for determining the efficiency of oval cell-mediated liver regeneration, focusing on the Notch signaling cascade.Methods: The established oval cell induction protocol of 2-acetylaminofluorine (2-AAF implantation followed by 70% surgical resection of the liver (partial hepatectomy, PH was employed in a rat model. This oval cell induction model was further combined with injections of a γ-secretase inhibitor (GSI XX to examine the effects of Notch inhibition on oval cell-aided regeneration of the liver.Results: Notch signaling was found to be upregulated at the peak of oval cell induction during 2AAF-PH alone. Treatment with GSI XX led to interruption of the Notch signal, as shown by a decrease in expression of Hes1. While there was a robust oval cell response seen at day 11 post-PH, there was a measurable delay in differentiation when Notch was inhibited. This was confirmed morphologically as well as by immunohistochemistry for the oval cell markers, α-fetoprotein, OV-6, and CK19. The hepatocytes seen at day 22 demonstrated an enhanced hepatocellular mitoinhibition index (p21Waf1/Ki67, suggestive of dysregulated proliferation and cell cycle progression. Moreover, these hepatocytes exhibited decreased expression of hepatocyte functional markers, such as cytochrome P450 and glucose-6-phosphatase-α.Conclusion: Taken together, these results identify the Notch signaling pathway as a potent regulator of differentiation and proliferation in

  16. Gefitinib Radiosensitizes Stem-Like Glioma Cells: Inhibition of Epidermal Growth Factor Receptor-Akt-DNA-PK Signaling, Accompanied by Inhibition of DNA Double-Strand Break Repair

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Khong Bee, E-mail: dmskkb@nccs.com.sg [Brain Tumour Research Laboratory, Division of Medical Sciences, National Cancer Centre Singapore (Singapore); Zhu Congju; Wong Yinling; Gao Qiuhan; Ty, Albert; Wong, Meng Cheong [Brain Tumour Research Laboratory, Division of Medical Sciences, National Cancer Centre Singapore (Singapore)

    2012-05-01

    Purpose: We compared radiosensitivity of brain tumor stem cells (BTSCs) with matched nonstem glioma cells, and determined whether gefitinib enhanced BTSC radiosensitivity by inhibiting epidermal growth factor receptor (EGFR)-Akt-DNA-dependent protein kinase (DNA-PK) signaling, followed by enhanced DNA double-stand breaks (DSBs) and inhibition of DSB repair. Methods and Materials: Radiosensitivity of stem-like gliomaspheres and nonstem glioma cells (obtained at patient neurosurgical resection) were evaluated by clonogenic assays, {gamma}-H{sub 2}AX immunostaining and cell cycle distribution. Survival of irradiated and nonirradiated NOD-SCID mice intracranially implanted with stem-like gliomaspheres were monitored. Glioma cells treated with gefitinib, irradiation, or both were assayed for clonogenic survival, {gamma}-H{sub 2}AX immunostaining, DNA-PKcs expression, and phosphorylation of EGFR and Akt. Results: Stem-like gliomaspheres displayed BTSC characteristics of self-renewal; differentiation into lineages of neurons, oligodendrocytes, and astrocytes; and initiation of glioma growth in NOD-SCID mice. Irradiation dose-dependently reduced clonogenic survival, induced G{sub 2}/M arrest and increased {gamma}-H{sub 2}AX immunostaining of nonstem glioma cells, but not stem-like gliomaspheres. There was no difference in survival of irradiated and nonirradiated mice implanted with stem-like gliomaspheres. The addition of gefitinib significantly inhibited clonogenic survival, increased {gamma}-H{sub 2}AX immunostaining, and reduced DNA-PKcs expression of irradiated stem-like gliomaspheres, without affecting irradiated-nonstem glioma cells. Gefitinib alone, and when combined with irradiation, inhibited phosphorylation of EGFR (Y1068 and Y1045) and Akt (S473) in stem-like gliomaspheres. In nonstem glioma cells, gefitinib alone inhibited EGFR Y1068 phosphorylation, with further inhibition by combined gefitinib and irradiation. Conclusions: Stem-like gliomaspheres are

  17. Gefitinib Radiosensitizes Stem-Like Glioma Cells: Inhibition of Epidermal Growth Factor Receptor-Akt-DNA-PK Signaling, Accompanied by Inhibition of DNA Double-Strand Break Repair

    International Nuclear Information System (INIS)

    Purpose: We compared radiosensitivity of brain tumor stem cells (BTSCs) with matched nonstem glioma cells, and determined whether gefitinib enhanced BTSC radiosensitivity by inhibiting epidermal growth factor receptor (EGFR)–Akt-DNA–dependent protein kinase (DNA-PK) signaling, followed by enhanced DNA double-stand breaks (DSBs) and inhibition of DSB repair. Methods and Materials: Radiosensitivity of stem-like gliomaspheres and nonstem glioma cells (obtained at patient neurosurgical resection) were evaluated by clonogenic assays, γ-H2AX immunostaining and cell cycle distribution. Survival of irradiated and nonirradiated NOD-SCID mice intracranially implanted with stem-like gliomaspheres were monitored. Glioma cells treated with gefitinib, irradiation, or both were assayed for clonogenic survival, γ-H2AX immunostaining, DNA-PKcs expression, and phosphorylation of EGFR and Akt. Results: Stem-like gliomaspheres displayed BTSC characteristics of self-renewal; differentiation into lineages of neurons, oligodendrocytes, and astrocytes; and initiation of glioma growth in NOD-SCID mice. Irradiation dose-dependently reduced clonogenic survival, induced G2/M arrest and increased γ-H2AX immunostaining of nonstem glioma cells, but not stem-like gliomaspheres. There was no difference in survival of irradiated and nonirradiated mice implanted with stem-like gliomaspheres. The addition of gefitinib significantly inhibited clonogenic survival, increased γ-H2AX immunostaining, and reduced DNA-PKcs expression of irradiated stem-like gliomaspheres, without affecting irradiated-nonstem glioma cells. Gefitinib alone, and when combined with irradiation, inhibited phosphorylation of EGFR (Y1068 and Y1045) and Akt (S473) in stem-like gliomaspheres. In nonstem glioma cells, gefitinib alone inhibited EGFR Y1068 phosphorylation, with further inhibition by combined gefitinib and irradiation. Conclusions: Stem-like gliomaspheres are resistant to irradiation-induced cytotoxicity, G2/M

  18. Quercetin induces caspase-dependent extrinsic apoptosis through inhibition of signal transducer and activator of transcription 3 signaling in HER2-overexpressing BT-474 breast cancer cells.

    Science.gov (United States)

    Seo, Hye-Sook; Ku, Jin Mo; Choi, Han-Seok; Choi, Youn Kyung; Woo, Jong-Kyu; Kim, Minsoo; Kim, Ilhwan; Na, Chang Hyeok; Hur, Hansol; Jang, Bo-Hyoung; Shin, Yong Cheol; Ko, Seong-Gyu

    2016-07-01

    Flavonoids are assumed to exert beneficial effects in different types of cancers at high concentrations. Yet, their molecular mechanisms of action remain unknown. The present study aimed to examine the effect of quercetin on proliferation and apoptosis in HER2-expressing breast cancer cells. The anti-proliferative effects of quercetin were examined by proliferation, MTT and clonogenic survival assays. The effect of quercetin on expression of apoptotic molecules was determined by western blotting. Luciferase reporter assay was performed to measure signal transducer and activator of transcription 3 (STAT3) transcriptional activity. ELISA assay was performed to measure intracellular MMP-9 levels. Immunocytochemistry was performed to evaluate the nuclear STAT3 level. The results revealed that quercetin inhibited the proliferation of BT-474 cells in a dose- and time-dependent manner. Quercetin also inhibited clonogenic survival (anchorage-dependent and -independent) of BT-474 cells in a dose-dependent manner. These growth inhibitions were accompanied with an increase in sub-G0/G1 apoptotic populations. Quercetin induced caspase-dependent extrinsic apoptosis upregulating the levels of cleaved caspase-8 and cleaved caspase-3, and inducing the cleavage of poly(ADP‑ribose) polymerase (PARP). In contrast, quercetin did not induce apoptosis via intrinsic mitochondrial apoptosis pathway since this compound did not decrease the mitochondrial membrane potential and did not affect the levels of B-cell lymphoma 2 (Bcl-2) and Bcl-2-associated X protein (BAX). Quercetin reduced the expression of phospho-JAK1 and phospho-STAT3 and decreased STAT3-dependent luciferase reporter gene activity in the BT-474 cells. Quercetin inhibited MMP-9 secretion and decreased the nuclear translocation of STAT3. Our study indicates that quercetin induces apoptosis at concentrations >20 µM through inhibition of STAT3 signaling and could serve as a useful compound to prevent or treat HER2

  19. Sensitivity of human lung adenocarcinoma cell lines to targeted inhibition of BET epigenetic signaling proteins

    OpenAIRE

    Lockwood, William W; Zejnullahu, Kreshnik; James E Bradner; Varmus, Harold

    2012-01-01

    Bromodomain and extra terminal domain (BET) proteins function as epigenetic signaling factors that associate with acetylated histones and facilitate transcription of target genes. Inhibitors targeting the activity of BET proteins have shown potent antiproliferative effects in hematological cancers through the suppression of c-MYC and downstream target genes. However, as the epigenetic landscape of a cell varies drastically depending on lineage, transcriptional coactivators such as BETs would ...

  20. Inhibition of Hedgehog-Signaling Driven Genes in Prostate Cancer Cells by Sutherlandia frutescens Extract.

    Directory of Open Access Journals (Sweden)

    Yuan Lu

    Full Text Available Sutherlandia frutescens (L R. Br. (Sutherlandia is a South African botanical that is traditionally used to treat a variety of health conditions, infections and diseases, including cancer. We hypothesized Sutherlandia might act through Gli/ Hedgehog (Hh-signaling in prostate cancer cells and used RNA-Seq transcription profiling to profile gene expression in TRAMPC2 murine prostate cancer cells with or without Sutherlandia extracts. We found 50% of Hh-responsive genes can be repressed by Sutherlandia ethanol extract, including the canonical Hh-responsive genes Gli1 and Ptch1 as well as newly distinguished Hh-responsive genes Hsd11b1 and Penk.

  1. Heterologous desensitization of T cell functions by CCR5 and CXCR4 ligands: inhibition of cellular signaling, adhesion and chemotaxis.

    Science.gov (United States)

    Hecht, Iris; Cahalon, Liora; Hershkoviz, Rami; Lahat, Adi; Franitza, Suzanne; Lider, Ofer

    2003-01-01

    T cells migrate into inflamed sites through the extracellular matrix (ECM) in response to chemotactic areas and are then simultaneously or sequentially exposed to multiple chemotactic ligands. We examined the responses of human peripheral blood T cells, present in an ECM-like context, to combinatorial signaling transduced by SDF-1alpha (CXCL12), and two CCR5 ligands, RANTES (CCL5) and MIP-1beta (CCL4). Separately, these chemokines, at G protein-coupled receptor (GPCR)-stimulating concentrations, induced T cell adhesion to fibronectin (FN) and T cell chemotaxis. However, the pro-adhesive and pro-migratory capacities of SDF-1alpha and RANTES or MIP-1beta were mutually suppressed by the simultaneous or sequential exposure of the cells to these CCR5 or CXCR4 ligands. This cross-talk did not involve the internalization of the SDF-1alpha receptor, CXCR4, but rather, a decrease in phosphorylation of ERK and Pyk-2, as well as inhibition of Ca(2+) mobilization. Strikingly, early CXCR4 signaling of phosphatidylinositol-3-kinase, detected by SDF-1alpha-induced AKT phosphorylation, was insensitive to RANTES-CCR5 signals. Accordingly, early chemotaxis to SDF-1alpha was not susceptible to CCR5 occupancy, whereas late stages of T cell chemotaxis were markedly down-regulated. This is an example of a specialized functional desensitization of heterologous chemokine receptors that induces GPCR interference with T cell adhesion to ECM ligands and chemotaxis within chemokine-rich extravascular contexts. PMID:12502723

  2. Pseudoephedrine inhibits T-cell activation by targeting NF-κB, NFAT and AP-1 signaling pathways.

    Science.gov (United States)

    Fiebich, Bernd L; Collado, Juan A; Stratz, Cristian; Valina, Christian; Hochholzer, Willibald; Muñoz, Eduardo; Bellido, Luz M

    2012-02-01

    Pseudoephedrine (PSE) is a stereoisomer of ephedrine that is commonly used as a nasal decongestant in combination with other anti-inflammatory drugs for the symptomatic treatment of some common pathologies such as common cold. Herein, we describe for the first time the effects of PSE on T-cell activation events. We found that PSE inhibits interleukin-2 (IL-2) and tumor necrosis factor (TNF) alpha-gene transcription in stimulated Jurkat cells, a human T-cell leukemia cell line. To further characterize the inhibitory mechanisms of PSE at the transcriptional level, we examined the transcriptional activities of nuclear factor kappa B (NF-κB), nuclear factor of activated T cells (NFAT), and activator protein-1 (AP-1) transcription factors and found that PSE inhibited NF-κB-dependent transcriptional activity without affecting either the phosphorylation, the degradation of the cytoplasmic NF-κB inhibitory protein, IκBα or the DNA-binding activity. However, phosphorylation of the p65/RelA subunit was clearly inhibited by PSE in stimulated cells. In addition, PSE inhibited the transcriptional activity of NFAT without interfering with the calcium-induced NFAT dephosphorylation event, which represents the major signaling pathway for its activation. NFAT cooperates with c-Jun, a compound of the AP-1 complex, to activate target genes, and we also found that PSE inhibited both JNK activation and AP-1 transcriptional activity. These findings provide new mechanistic insights into the potential immunomodulatory activities of PSE and highlight their potential in designing novel therapeutic strategies to manage inflammatory diseases.

  3. Trichosanthin suppresses the proliferation of glioma cells by inhibiting LGR5 expression and the Wnt/β-catenin signaling pathway.

    Science.gov (United States)

    Miao, Junjie; Jiang, Yilin; Wang, Dongliang; Zhou, Jingru; Fan, Cungang; Jiao, Feng; Liu, Bo; Zhang, Jun; Wang, Yangshuo; Zhang, Qingjun

    2015-12-01

    Studies have indicated that trichosanthin (TCS), a bioactive protein extracted and purified from the tuberous root of Trichosanthes kirilowii (a well‑known traditional Chinese medicinal plant), produces antitumor effects on various types of cancer cells. However, the effects of TCS on glioma cells are poorly understood. The objective of this study was to investigate the antitumor effects of TCS on the U87 and U251 cell lines. The in vitro effects of TCS on these two cell lines were determined using a Cell Counting Kit‑8 (CCK‑8) assay, Annexin V‑FITC staining, DAPI staining, Transwell assays, terminal deoxynucleotidyl transferase‑mediated dUTP nick end‑labeling (TUNEL) assays, 5,5',6,6'‑tetrachloro‑1,1',3,3'‑tetraethyl‑imidacarbocyanine iodide (JC‑1) staining and western blotting, which was utilized to assess the expression of leucine‑rich repeat‑containing G protein‑coupled receptor 5 (LGR5) and key proteins in the Wnt/β‑catenin signaling pathway. Our data indicated that TCS inhibited the proliferation of glioma cells in a dose‑ and time‑dependent manner and played a role in inhibiting glioma cell invasion and migration. Additional investigation revealed that the expression levels of LGR5 and of key proteins in the Wnt/β‑catenin signaling pathway were markedly decreased after TCS treatment. The results suggest that TCS may induce apoptosis in glioma cells by targeting LGR5 and repressing the Wnt/β‑catenin signaling pathway. In the future, in vivo experiments should be conducted to examine the potential use of this compound as a novel therapeutic agent for gliomas.

  4. Inhibition of IL-1R1/MyD88 signalling promotes mesenchymal stem cell-driven tissue regeneration.

    Science.gov (United States)

    Martino, Mikaël M; Maruyama, Kenta; Kuhn, Gisela A; Satoh, Takashi; Takeuchi, Osamu; Müller, Ralph; Akira, Shizuo

    2016-03-22

    Tissue injury and the healing response lead to the release of endogenous danger signals including Toll-like receptor (TLR) and interleukin-1 receptor, type 1 (IL-1R1) ligands, which modulate the immune microenvironment. Because TLRs and IL-1R1 have been shown to influence the repair process of various tissues, we explored their role during bone regeneration, seeking to design regenerative strategies integrating a control of their signalling. Here we show that IL-1R1/MyD88 signalling negatively regulates bone regeneration, in the mouse. Furthermore, IL-1β which is released at the bone injury site, inhibits the regenerative capacities of mesenchymal stem cells (MSCs). Mechanistically, IL-1R1/MyD88 signalling impairs MSC proliferation, migration and differentiation by inhibiting the Akt/GSK-3β/β-catenin pathway. Lastly, as a proof of concept, we engineer a MSC delivery system integrating inhibitors of IL-1R1/MyD88 signalling. Using this strategy, we considerably improve MSC-based bone regeneration in the mouse, demonstrating that this approach may be useful in regenerative medicine applications.

  5. Inhibition of p300 histone acetyltransferase activity in palate mesenchyme cells attenuates Wnt signaling via aberrant E-cadherin expression.

    Science.gov (United States)

    Warner, Dennis R; Smith, Scott C; Smolenkova, Irina A; Pisano, M Michele; Greene, Robert M

    2016-03-01

    p300 is a multifunctional transcriptional coactivator that interacts with numerous transcription factors and exhibits protein/histone acetyltransferase activity. Loss of p300 function in humans and in mice leads to craniofacial defects. In this study, we demonstrated that inhibition of p300 histone acetyltransferase activity with the compound, C646, altered the expression of several genes, including Cdh1 (E-cadherin) in mouse maxillary mesenchyme cells, which are the cells that give rise to the secondary palate. The increased expression of plasma membrane-bound E-cadherin was associated with reduced cytosolic β-catenin, that led to attenuated signaling through the canonical Wnt pathway. Furthermore, C646 reduced both cell proliferation and the migratory ability of these cells. These results suggest that p300 histone acetyltransferase activity is critical for Wnt-dependent palate mesenchymal cell proliferation and migration, both processes that play a significant role in morphogenesis of the palate.

  6. Quercetin inhibits migration and invasion of SAS human oral cancer cells through inhibition of NF-κB and matrix metalloproteinase-2/-9 signaling pathways.

    Science.gov (United States)

    Lai, Wan-Wen; Hsu, Shu-Chun; Chueh, Fu-Shih; Chen, Ya-Yin; Yang, Jai-Sing; Lin, Jing-Pin; Lien, Jin-Cherng; Tsai, Chung-Hung; Chung, Jing-Gung

    2013-05-01

    Quercetin, a principal flavanoid compound in onions, has been shown to possess a wide spectrum of pharmacological properties, including anticancer activities. Our earlier study showed that quercetin induced cytotoxic effects on SAS human oral cancer cells. In this study, we found that quercetin significantly reduced wound closure of SAS cells in culture plates after 12- and 24-h treatments. Results indicated that quercetin inhibited the expression and activity of matrix metalloproteinase (MMP)-2 and MMP-9, as measured by western blotting and gelatin zymography. The results from western blotting also showed that quercetin reduced the protein levels of MMP-2, -7, -9 and -10, vascular endothelial growth factor (VEGF), nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) p65, inductible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), urokinase-type plasminogen activator (uPA), phosphatidylinositide-3 kinases (PI3K), nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor, alpha (IKBα), IKB-α/β, phosphorylated nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor kinase, alpha/beta (p-IKKα/β), focal adhesion kinase (FAK), son of sevenless homolog-1 (SOS1), growth factor receptor-bound protein-2 (GRB2), mitogen-activated protein kinase kinase kinase-3 (MEKK3), MEKK7, extracellular-signal-regulated kinase 1/2 (ERK1/2), p-ERK1/2, c-Jun N-terminal kinase 1/2 (JNK1/2), p38, p-p38, Jun proto-oncogene (c-JUN) and p-c-JUN but it did not affect Ras homolog gene family, member A (RhoA), Protein kinase C (PKC) and rat sarcoma viral oncogene homolog (RAS) in SAS cells. Confocal laser microscopy also showed that quercetin promoted the expressions of RhoA and Rho-associated, coiled-coil containing protein kinase-1 (ROCK1), but inhibited the expression of NF-κB p65 in SAS cells. It is concluded from these data that inhibition of migration and invasion of SAS cells by quercetin is associated with the down

  7. IL-24 inhibits lung cancer cell migration and invasion by disrupting the SDF-1/CXCR4 signaling axis.

    Directory of Open Access Journals (Sweden)

    Janani Panneerselvam

    Full Text Available BACKGROUND: The stromal cell derived factor (SDF-1/chemokine receptor (CXCR-4 signaling pathway plays a key role in lung cancer metastasis and is molecular target for therapy. In the present study we investigated whether interleukin (IL-24 can inhibit the SDF-1/CXCR4 axis and suppress lung cancer cell migration and invasion in vitro. Further, the efficacy of IL-24 in combination with CXCR4 antagonists was investigated. METHODS: Human H1299, A549, H460 and HCC827 lung cancer cell lines were used in the present study. The H1299 lung cancer cell line was stably transfected with doxycycline-inducible plasmid expression vector carrying the human IL-24 cDNA and used in the present study to determine the inhibitory effects of IL-24 on SDF-1/CXCR4 axis. H1299 and A549 cell lines were used in transient transfection studies. The inhibitory effects of IL-24 on SDF1/CXCR4 and its downstream targets were analyzed by quantitative RT-PCR, western blot, luciferase reporter assay, flow cytometry and immunocytochemistry. Functional studies included cell migration and invasion assays. PRINCIPAL FINDINGS: Endogenous CXCR4 protein expression levels varied among the four human lung cancer cell lines. Doxycycline-induced IL-24 expression in the H1299-IL24 cell line resulted in reduced CXCR4 mRNA and protein expression. IL-24 post-transcriptionally regulated CXCR4 mRNA expression by decreasing the half-life of CXCR4 mRNA (>40%. Functional studies showed IL-24 inhibited tumor cell migration and invasion concomitant with reduction in CXCR4 and its downstream targets (pAKTS473, pmTORS2448, pPRAS40T246 and HIF-1α. Additionally, IL-24 inhibited tumor cell migration both in the presence and absence of the CXCR4 agonist, SDF-1. Finally, IL-24 when combined with CXCR4 inhibitors (AMD3100, SJA5 or with CXCR4 siRNA demonstrated enhanced inhibitory activity on tumor cell migration. CONCLUSIONS: IL-24 disrupts the SDF-1/CXCR4 signaling pathway and inhibits lung tumor cell

  8. Escin Chemosensitizes Human Pancreatic Cancer Cells and Inhibits the Nuclear Factor-kappaB Signaling Pathway.

    Science.gov (United States)

    Rimmon, A; Vexler, A; Berkovich, L; Earon, G; Ron, I; Lev-Ari, S

    2013-01-01

    Background. There is an urgent need to develop new treatment strategies and drugs for pancreatic cancer that is highly resistant to radio-chemotherapy. Aesculus hippocastanum (the horse chestnut) known in Chinese medicine as a plant with anti-inflammatory, antiedema, antianalgesic, and antipyretic activities. The main active compound of this plant is Escin (C54H84O23). Objective. To evaluate the effect of Escin alone and combined with chemotherapy on pancreatic cancer cell survival and to unravel mechanism(s) of Escin anticancer activity. Methods. Cell survival was measured by XTT colorimetric assay. Synergistic effect of combined therapy was determined by CalcuSyn software. Cell cycle and induction of apoptosis were evaluated by FACS analysis. Expression of NF- κ B-related proteins (p65, I κ Bα, and p-I κ Bα) and cyclin D was evaluated by western blot analysis. Results. Escin decreased the survival of pancreatic cancer cells with IC50 = 10-20 M. Escin combined with gemcitabine showed only additive effect, while its combination with cisplatin resulted in a significant synergistic cytotoxic effect in Panc-1 cells. High concentrations of Escin induced apoptosis and decreased NF- κ B-related proteins and cyclin D expression. Conclusions. Escin decreased pancreatic cancer cell survival, induced apoptosis, and downregulated NF- κ B signaling pathway. Moreover, Escin sensitized pancreatic cancer cells to chemotherapy. Further translational research is required. PMID:24282639

  9. Escin Chemosensitizes Human Pancreatic Cancer Cells and Inhibits the Nuclear Factor-kappaB Signaling Pathway

    Directory of Open Access Journals (Sweden)

    A. Rimmon

    2013-01-01

    Full Text Available Background. There is an urgent need to develop new treatment strategies and drugs for pancreatic cancer that is highly resistant to radio-chemotherapy. Aesculus hippocastanum (the horse chestnut known in Chinese medicine as a plant with anti-inflammatory, antiedema, antianalgesic, and antipyretic activities. The main active compound of this plant is Escin (C54H84O23. Objective. To evaluate the effect of Escin alone and combined with chemotherapy on pancreatic cancer cell survival and to unravel mechanism(s of Escin anticancer activity. Methods. Cell survival was measured by XTT colorimetric assay. Synergistic effect of combined therapy was determined by CalcuSyn software. Cell cycle and induction of apoptosis were evaluated by FACS analysis. Expression of NF-κB-related proteins (p65, IκBα, and p-IκBα and cyclin D was evaluated by western blot analysis. Results. Escin decreased the survival of pancreatic cancer cells with IC50 = 10–20 M. Escin combined with gemcitabine showed only additive effect, while its combination with cisplatin resulted in a significant synergistic cytotoxic effect in Panc-1 cells. High concentrations of Escin induced apoptosis and decreased NF-κB-related proteins and cyclin D expression. Conclusions. Escin decreased pancreatic cancer cell survival, induced apoptosis, and downregulated NF-κB signaling pathway. Moreover, Escin sensitized pancreatic cancer cells to chemotherapy. Further translational research is required.

  10. SENP1 inhibition induces apoptosis and growth arrest of multiple myeloma cells through modulation of NF-κB signaling

    International Nuclear Information System (INIS)

    SUMO/sentrin specific protease 1 (Senp1) is an important regulation protease in the protein sumoylation, which affects the cell cycle, proliferation and differentiation. The role of Senp1 mediated protein desumoylation in pathophysiological progression of multiple myeloma is unknown. In this study, we demonstrated that Senp1 is overexpressed and induced by IL-6 in multiple myeloma cells. Lentivirus-mediated Senp1 knockdown triggers apoptosis and reduces viability, proliferation and colony forming ability of MM cells. The NF-κB family members including P65 and inhibitor protein IkBα play important roles in regulation of MM cell survival and proliferation. We further demonstrated that Senp1 inhibition decreased IL-6-induced P65 and IkBα phosphorylation, leading to inactivation of NF-kB signaling in MM cells. These results delineate a key role for Senp1in IL-6 induced proliferation and survival of MM cells, suggesting it may be a potential new therapeutic target in MM. - Highlights: • Senp1 is overexpressed and induced by IL-6 in multiple myeloma cells. • Senp1 knockdown triggers apoptosis and reduces proliferation of MM cells. • Senp1 inhibition decreased IL-6-induced P65 and IkBα phosphorylation

  11. SENP1 inhibition induces apoptosis and growth arrest of multiple myeloma cells through modulation of NF-κB signaling

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Jun [Graduate School of Anhui Medical University, Hefei (China); Department of Experimental Hematology, Beijing Institute of Radiation Medicine, Beijing 100850 (China); Sun, Hui-Yan; Xiao, Feng-Jun; Wang, Hua [Department of Experimental Hematology, Beijing Institute of Radiation Medicine, Beijing 100850 (China); Yang, Yang [Department of Hematology, General Hospital of Air Force, Beijing (China); Wang, Lu; Gao, Chun-Ji [Department of Hematology, PLA General Hospital, Beijing (China); Guo, Zi-Kuan [Department of Experimental Hematology, Beijing Institute of Radiation Medicine, Beijing 100850 (China); Wu, Chu-Tse [Department of Experimental Hematology, Beijing Institute of Radiation Medicine, Beijing 100850 (China); Collaborative Innovation Center for Biotherapy, West China Hospital, Sichuan University, Chengdu (China); Wang, Li-Sheng, E-mail: Wangls@bmi.ac.cn [Department of Experimental Hematology, Beijing Institute of Radiation Medicine, Beijing 100850 (China); Collaborative Innovation Center for Biotherapy, West China Hospital, Sichuan University, Chengdu (China)

    2015-05-01

    SUMO/sentrin specific protease 1 (Senp1) is an important regulation protease in the protein sumoylation, which affects the cell cycle, proliferation and differentiation. The role of Senp1 mediated protein desumoylation in pathophysiological progression of multiple myeloma is unknown. In this study, we demonstrated that Senp1 is overexpressed and induced by IL-6 in multiple myeloma cells. Lentivirus-mediated Senp1 knockdown triggers apoptosis and reduces viability, proliferation and colony forming ability of MM cells. The NF-κB family members including P65 and inhibitor protein IkBα play important roles in regulation of MM cell survival and proliferation. We further demonstrated that Senp1 inhibition decreased IL-6-induced P65 and IkBα phosphorylation, leading to inactivation of NF-kB signaling in MM cells. These results delineate a key role for Senp1in IL-6 induced proliferation and survival of MM cells, suggesting it may be a potential new therapeutic target in MM. - Highlights: • Senp1 is overexpressed and induced by IL-6 in multiple myeloma cells. • Senp1 knockdown triggers apoptosis and reduces proliferation of MM cells. • Senp1 inhibition decreased IL-6-induced P65 and IkBα phosphorylation.

  12. AB109. Downregulation of tNASP inhibits proliferation through regulating cell cycle-related proteins and inactive ERK/MAPK signal pathway in renal cell carcinoma cells

    Science.gov (United States)

    Fang, Jianzheng; Wang, Hainan; Cheng, Gong; Wang, Shangqian; Deng, Yunfei; Song, Zhen; Xu, Aiming; Liu, Bianjiang; Wang, Zengjun

    2016-01-01

    Objective Nuclear auto-antigenic sperm protein (NASP), initially described as a highly auto-immunogenic testis and sperm-specific protein, is a histone chaperone that is proved to present in all dividing cells. NASP has two splice variants: testicular NASP (tNASP) and somatic form of NASP (sNASP). Only cancer, germ, transformed, and embryonic cells have a high level of expression of the tNASP. Up to now, little has been known about tNASP in renal cell carcinoma (RCC). In the present study, the molecular mechanism of tNASP in RCC was explored. Methods The expression level of tNASP in 16 paired human RCC specimens was determined. Downregulation of tNASP by small interfering RNA (siRNA) was transfected in RCC cell lines. The effect of downregulation of tNASP by siRNA on cell colony formation and proliferation was examined by colony formation assay and CCK-8 assay, cell cycle was analyzed by flow cytometry, and the expression of cyclin D1 and P21 were detected by Western blotting. ERK/MAPK signaling was also analyzed. Results tNASP has a relative high expression level in human RCC tissues. Via upregulation of P21 and downregulation of cyclinD1, silence of tNASP can inhibit cell proliferation, which induces cell cycle arrest. Furthermore, ERK signaling pathway is confirmed to mediate the regulation of cell cycle-related proteins caused by silence of tNASP. Conclusions Our research demonstrates that knockdown of tNASP effectively inhibits the proliferation and causes G1 phase arrest through ERK/MAPK signal pathway.

  13. Luteolin inhibits Cr(VI)-induced malignant cell transformation of human lung epithelial cells by targeting ROS mediated multiple cell signaling pathways

    Energy Technology Data Exchange (ETDEWEB)

    Pratheeshkumar, Poyil; Son, Young-Ok; Divya, Sasidharan Padmaja; Roy, Ram Vinod; Hitron, John Andrew; Wang, Lei [Center for Research on Environmental Disease, University of Kentucky, 1095 VA Drive, Lexington, KY 40536 (United States); Graduate Center for Toxicology, University of Kentucky, 1095 VA Drive, Lexington, KY 40536 (United States); Kim, Donghern; Dai, Jin [Graduate Center for Toxicology, University of Kentucky, 1095 VA Drive, Lexington, KY 40536 (United States); Asha, Padmaja [National Centre for Aquatic Animal Health, Cochin University of Science and Technology, Cochin (India); Zhang, Zhuo [Graduate Center for Toxicology, University of Kentucky, 1095 VA Drive, Lexington, KY 40536 (United States); Wang, Yitao [State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macau (China); Shi, Xianglin, E-mail: xshi5@email.uky.edu [Center for Research on Environmental Disease, University of Kentucky, 1095 VA Drive, Lexington, KY 40536 (United States); Graduate Center for Toxicology, University of Kentucky, 1095 VA Drive, Lexington, KY 40536 (United States)

    2014-12-01

    Hexavalent chromium [Cr(VI)] is a well-known human carcinogen associated with the incidence of lung cancer. Inhibition of metal induced carcinogenesis by a dietary antioxidant is a novel approach. Luteolin, a natural dietary flavonoid found in fruits and vegetables, possesses potent antioxidant and anti-inflammatory activity. We found that short term exposure of human bronchial epithelial cells (BEAS-2B) to Cr(VI) (5 μM) showed a drastic increase in ROS generation, NADPH oxidase (NOX) activation, lipid peroxidation, and glutathione depletion, which were significantly inhibited by the treatment with luteolin in a dose dependent manner. Treatment with luteolin decreased AP-1, HIF-1α, COX-2, and iNOS promoter activity induced by Cr(VI) in BEAS-2B cells. In addition, luteolin protected BEAS-2B cells from malignant transformation induced by chronic Cr(VI) exposure. Moreover, luteolin also inhibited the production of pro-inflammatory cytokines (IL-1β, IL-6, IL-8, TNF-α) and VEGF in chronic Cr(VI) exposed BEAS-2B cells. Western blot analysis showed that luteolin inhibited multiple gene products linked to survival (Akt, Fak, Bcl-2, Bcl-xL), inflammation (MAPK, NF-κB, COX-2, STAT-3, iNOS, TNF-α) and angiogenesis (HIF-1α, VEGF, MMP-9) in chronic Cr(VI) exposed BEAS-2B cells. Nude mice injected with BEAS-2B cells chronically exposed to Cr(VI) in the presence of luteolin showed reduced tumor incidence compared to Cr(VI) alone treated group. Overexpression of catalase (CAT) or SOD2, eliminated Cr(VI)-induced malignant transformation. Overall, our results indicate that luteolin protects BEAS-2B cells from Cr(VI)-induced carcinogenesis by scavenging ROS and modulating multiple cell signaling mechanisms that are linked to ROS. Luteolin, therefore, serves as a potential chemopreventive agent against Cr(VI)-induced carcinogenesis. - Highlights: • Luteolin inhibited Cr(VI)-induced oxidative stress. • Luteolin inhibited chronic Cr(VI)-induced malignant transformation.

  14. Inhibition of N-linked glycosylation impairs ALK phosphorylation and disrupts pro-survival signaling in neuroblastoma cell lines

    Directory of Open Access Journals (Sweden)

    Del Grosso Federica

    2011-12-01

    involved in cell death. Conclusions In this study we showed that inhibition of N-linked glycosylation affects ALK phosphorylation and disrupts downstream pro-survival signaling, indicating that inhibition of this post-translational modification may be a promising therapeutic approach. However, as tunicamycin is not a likely candidate for clinical use other approaches to alter N-linked glycosylation need to be explored. Future studies will assess whether the efficacy in inhibiting ALK activity might be enhanced by the combination of ALK specific small molecule and N-linked glycosylation inhibitors.

  15. Honokiol inhibits non-small cell lung cancer cell migration by targeting PGE₂-mediated activation of β-catenin signaling.

    Science.gov (United States)

    Singh, Tripti; Katiyar, Santosh K

    2013-01-01

    Lung cancer remains a leading cause of death due to its metastasis to distant organs. We have examined the effect of honokiol, a bioactive constituent from the Magnolia plant, on human non-small cell lung cancer (NSCLC) cell migration and the molecular mechanisms underlying this effect. Using an in vitro cell migration assay, we found that treatment of A549, H1299, H460 and H226 NSCLC cells with honokiol resulted in inhibition of migration of these cells in a dose-dependent manner, which was associated with a reduction in the levels of cyclooxygenase-2 (COX-2) and prostaglandin E2 (PGE2). Celecoxib, a COX-2 inhibitor, also inhibited cell migration. Honokiol inhibited PGE2-enhanced migration of NSCLC cells, inhibited the activation of NF-κB/p65, an upstream regulator of COX-2, in A549 and H1299 cells, and treatment of cells with caffeic acid phenethyl ester, an inhibitor of NF-κB, also inhibited migration of NSCLC cells. PGE2 has been shown to activate β-catenin signaling, which contributes to cancer cell migration. Therefore, we checked the effect of honokiol on β-catenin signaling. It was observed that treatment of NSCLC cells with honokiol degraded cytosolic β-catenin, reduced nuclear accumulation of β-catenin and down-regulated matrix metalloproteinase (MMP)-2 and MMP-9, which are the down-stream targets of β-catenin and play a crucial role in cancer cell metastasis. Honokiol enhanced: (i) the levels of casein kinase-1α, glycogen synthase kinase-3β, and (ii) phosphorylation of β-catenin on critical residues Ser(45), Ser(33/37) and Thr(41). These events play important roles in degradation or inactivation of β-catenin. Treatment of celecoxib also reduced nuclear accumulation of β-catenin in NSCLC cells. FH535, an inhibitor of Wnt/β-catenin pathway, inhibited PGE2-enhanced cell migration of A549 and H1299 cells. These results indicate that honokiol inhibits non-small cell lung cancer cells migration by targeting PGE2-mediated activation of

  16. Honokiol inhibits non-small cell lung cancer cell migration by targeting PGE₂-mediated activation of β-catenin signaling.

    Directory of Open Access Journals (Sweden)

    Tripti Singh

    Full Text Available Lung cancer remains a leading cause of death due to its metastasis to distant organs. We have examined the effect of honokiol, a bioactive constituent from the Magnolia plant, on human non-small cell lung cancer (NSCLC cell migration and the molecular mechanisms underlying this effect. Using an in vitro cell migration assay, we found that treatment of A549, H1299, H460 and H226 NSCLC cells with honokiol resulted in inhibition of migration of these cells in a dose-dependent manner, which was associated with a reduction in the levels of cyclooxygenase-2 (COX-2 and prostaglandin E2 (PGE2. Celecoxib, a COX-2 inhibitor, also inhibited cell migration. Honokiol inhibited PGE2-enhanced migration of NSCLC cells, inhibited the activation of NF-κB/p65, an upstream regulator of COX-2, in A549 and H1299 cells, and treatment of cells with caffeic acid phenethyl ester, an inhibitor of NF-κB, also inhibited migration of NSCLC cells. PGE2 has been shown to activate β-catenin signaling, which contributes to cancer cell migration. Therefore, we checked the effect of honokiol on β-catenin signaling. It was observed that treatment of NSCLC cells with honokiol degraded cytosolic β-catenin, reduced nuclear accumulation of β-catenin and down-regulated matrix metalloproteinase (MMP-2 and MMP-9, which are the down-stream targets of β-catenin and play a crucial role in cancer cell metastasis. Honokiol enhanced: (i the levels of casein kinase-1α, glycogen synthase kinase-3β, and (ii phosphorylation of β-catenin on critical residues Ser(45, Ser(33/37 and Thr(41. These events play important roles in degradation or inactivation of β-catenin. Treatment of celecoxib also reduced nuclear accumulation of β-catenin in NSCLC cells. FH535, an inhibitor of Wnt/β-catenin pathway, inhibited PGE2-enhanced cell migration of A549 and H1299 cells. These results indicate that honokiol inhibits non-small cell lung cancer cells migration by targeting PGE2-mediated activation of

  17. Inhibition of receptor tyrosine kinase signalling by small molecule agonist of T-cell protein tyrosine phosphatase

    Directory of Open Access Journals (Sweden)

    Tähtinen Siri

    2010-01-01

    Full Text Available Abstract Background T-cell protein tyrosine phosphatase (TCPTP/TC45 is a ubiquitously expressed intra-cellular non-receptor protein tyrosine phosphatase involved in the negative regulation of several cancer relevant cellular signalling pathways. We have previously shown that interaction between the α-cytoplasmic tail of α1β1 integrin and TCPTP activates TCPTP by disrupting an inhibitory intra-molecular bond in TCPTP. Thus, inhibition of the regulatory interaction in TCPTP is a desirable strategy for TCPTP activation and attenuation of oncogenic RTK signalling. However, this is challenging with low molecular weight compounds. Methods We developed a high-throughput compatible assay to analyse activity of recombinant TCPTP in vitro. Using this assay we have screened 64280 small molecules to identify novel agonists for TCPTP. Dose-dependent response to TCPTP agonist was performed using the in vitro assay. Inhibition effects and specificity of TCPTP agonists were evaluated using TCPTP expressing and null mouse embryonic fibroblasts. Western blot analysis was used to evaluate attenuation of PDGFRβ and EGFR phosphorylation. Inhibition of VEGF signalling was analysed with VEGF-induced endothelial cell sprouting assays. Results From the screen we identified six TCPTP agonists. Two compounds competed with α1-cytoplasmic domain for binding to TCPTP, suggesting that they activate TCPTP similar to α1-cyt by disrupting the intra-molecular bond in TCPTP. Importantly, one of the compounds (spermidine displayed specificity towards TCPTP in cells, since TCPTP -/- cells were 43-fold more resistant to the compound than TCPTP expressing cells. This compound attenuates PDGFRβ and VEGFR2 signalling in cells in a TCPTP-dependent manner and functions as a negative regulator of EGFR phosphorylation in cancer cells. Conclusions In this study we showed that small molecules mimicking TCPTP-α1 interaction can be used as TCPTP agonists. These data provide the first

  18. Electroacupuncture in the repair of spinal cord injury: inhibiting the Notch signaling pathway and promoting neural stem cell proliferation

    Directory of Open Access Journals (Sweden)

    Xin Geng

    2015-01-01

    Full Text Available Electroacupuncture for the treatment of spinal cord injury has a good clinical curative effect, but the underlying mechanism is unclear. In our experiments, the spinal cord of adult Sprague-Dawley rats was clamped for 60 seconds. Dazhui (GV14 and Mingmen (GV4 acupoints of rats were subjected to electroacupuncture. Enzyme-linked immunosorbent assay revealed that the expression of serum inflammatory factors was apparently downregulated in rat models of spinal cord injury after electroacupuncture. Hematoxylin-eosin staining and immunohistochemistry results demonstrated that electroacupuncture contributed to the proliferation of neural stem cells in rat injured spinal cord, and suppressed their differentiation into astrocytes. Real-time quantitative PCR and western blot assays showed that electroacupuncture inhibited activation of the Notch signaling pathway induced by spinal cord injury. These findings indicate that electroacupuncture repaired the injured spinal cord by suppressing the Notch signaling pathway and promoting the proliferation of endogenous neural stem cells.

  19. Electroacupuncture in the repair of spinal cord injury:inhibiting the Notch signaling pathway and promoting neural stem cell proliferation

    Institute of Scientific and Technical Information of China (English)

    Xin Geng; Tao Sun; Jing-hui Li; Ning Zhao; Yong Wang; Hua-lin Yu

    2015-01-01

    Electroacupuncture for the treatment of spinal cord injury has a good clinical curative effect, but the underlying mechanism is unclear. In our experiments, the spinal cord of adult Sprague-Daw-ley rats was clamped for 60 seconds.Dazhui (GV14) andMingmen (GV4) acupoints of rats were subjected to electroacupuncture. Enzyme-linked immunosorbent assay revealed that the expres-sion of serum inlfammatory factors was apparently downregulated in rat models of spinal cord injury after electroacupuncture. Hematoxylin-eosin staining and immunohistochemistry results demonstrated that electroacupuncture contributed to the proliferation of neural stem cells in rat injured spinal cord, and suppressed their differentiation into astrocytes. Real-time quantitative PCR and western blot assays showed that electroacupuncture inhibited activation of the Notch signaling pathway induced by spinal cord injury. These ifndings indicate that electroacupuncture repaired the injured spinal cord by suppressing the Notch signaling pathway and promoting the proliferation of endogenous neural stem cells.

  20. Curcumin Promotes Cell Cycle Arrest and Inhibits Survival of Human Renal Cancer Cells by Negative Modulation of the PI3K/AKT Signaling Pathway.

    Science.gov (United States)

    Zhang, Hao; Xu, Weili; Li, Baolin; Zhang, Kai; Wu, Yudong; Xu, Haidong; Wang, Junyong; Zhang, Jun; Fan, Rui; Wei, Jinxing

    2015-12-01

    Curcumin possesses anti-cancer effects. In the current study, we tested the effect of curcumin on cell proliferation, viability, apoptosis, cell cycle phases, and activation of the PI3K/Akt pathway in the renal cell carcinoma (RCC) cell line RCC-949. We observed that cell proliferation and viability were markedly inhibited by curcumin, while cell apoptosis was promoted. The latter effect was associated with increased expression of Bcl-2 and diminished expression of Bax (both: mRNA and protein). The cells treated with curcumin increasingly went into cell cycle arrest, which was likely mediated by diminished expression of cyclin B1, as seen in curcumin-treated cells. In addition, curcumin decreased activation of the PI3K/AKT signaling pathway. In conclusion, our results demonstrate that curcumin exerts anti-cancer effects by negative modulation of the PI3K/AKT signaling pathway and may represent a promising new drug to treat RCC. PMID:27259310

  1. Ibrutinib inhibits BCR and NF-κB signaling and reduces tumor proliferation in tissue-resident cells of patients with CLL

    OpenAIRE

    Herman, Sarah E. M.; Mustafa, Rashida Z.; Gyamfi, Jennifer A.; Pittaluga, Stefania; Chang, Stella; Chang, Betty; Farooqui, Mohammed; Wiestner, Adrian

    2014-01-01

    Ibrutinib inhibits both BCR and NF-κB signaling in lymph node and bone marrow resident CLL cells.Rapid and sustained reduction of cellular activation and tumor proliferation was achieved in all anatomic compartments.

  2. MEK5/ERK5 signaling inhibition increases colon cancer cell sensitivity to 5-fluorouracil through a p53-dependent mechanism

    Science.gov (United States)

    Pereira, Diane M.; Simões, André E. S.; Gomes, Sofia E.; Castro, Rui E.; Carvalho, Tânia; Rodrigues, Cecília M. P.; Borralho, Pedro M.

    2016-01-01

    The MEK5/ERK5 signaling pathway is emerging as an important contributor to colon cancer onset, progression and metastasis; however, its relevance to chemotherapy resistance remains unknown. Here, we evaluated the impact of the MEK5/ERK5 cascade in colon cancer cell sensitivity to 5-fluorouracil (5-FU). Increased ERK5 expression was correlated with poor overall survival in colon cancer patients. In colon cancer cells, 5-FU exposure impaired endogenous KRAS/MEK5/ERK5 expression and/or activation. In turn, MEK5 constitutive activation reduced 5-FU-induced cytotoxicity. Using genetic and pharmacological approaches, we showed that ERK5 inhibition increased caspase-3/7 activity and apoptosis following 5-FU exposure. Mechanistically, this was further associated with increased p53 transcriptional activation of p21 and PUMA. In addition, ERK5 inhibition increased the response of HCT116 p53+/+ cells to 5-FU, but failed to sensitize HCT116 p53−/− cells to the cytotoxic effects of this chemotherapeutic agent, suggesting a p53-dependent axis mediating 5-FU sensitization. Finally, ERK5 inhibition using XMD8-92 was shown to increase the antitumor effects of 5-FU in a murine subcutaneous xenograft model, enhancing apoptosis while markedly reducing tumor growth. Collectively, our results suggest that ERK5-targeted in hibition provides a promising therapeutic approach to overcome resistance to 5-FU-based chemotherapy and improve colon cancer treatment. PMID:27144434

  3. Biphasic role of chondroitin sulfate in cardiac differentiation of embryonic stem cells through inhibition of Wnt/β-catenin signaling.

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    Robert D Prinz

    Full Text Available The glycosaminoglycan chondroitin sulfate is a critical component of proteoglycans on the cell surface and in the extracellular matrix. As such, chondroitin sulfate side chains and the sulfation balance of chondroitin play important roles in the control of signaling pathways, and have a functional importance in human disease. In contrast, very little is known about the roles of chondroitin sulfate molecules and sulfation patterns during mammalian development and cell lineage specification. Here, we report a novel biphasic role of chondroitin sulfate in the specification of the cardiac cell lineage during embryonic stem cell differentiation through modulation of Wnt/beta-catenin signaling. Lineage marker analysis demonstrates that enzymatic elimination of endogenous chondroitin sulfates leads to defects specifically in cardiac differentiation. This is accompanied by a reduction in the number of beating cardiac foci. Mechanistically, we show that endogenous chondroitin sulfate controls cardiac differentiation in a temporal biphasic manner through inhibition of the Wnt/beta-catenin pathway, a known regulatory pathway for the cardiac lineage. Treatment with a specific exogenous chondroitin sulfate, CS-E, could mimic these biphasic effects on cardiac differentiation and Wnt/beta-catenin signaling. These results establish chondroitin sulfate and its sulfation balance as important regulators of cardiac cell lineage decisions through control of the Wnt/beta-catenin pathway. Our work suggests that targeting the chondroitin biosynthesis and sulfation machinery is a novel promising avenue in regenerative strategies after heart injury.

  4. CRM1 Inhibition Promotes Cytotoxicity in Ewing Sarcoma Cells by Repressing EWS-FLI1-Dependent IGF-1 Signaling.

    Science.gov (United States)

    Sun, Haibo; Lin, De-Chen; Cao, Qi; Guo, Xiao; Marijon, Helene; Zhao, Zhiqiang; Gery, Sigal; Xu, Liang; Yang, Henry; Pang, Brendan; Lee, Victor Kwan Min; Lim, Huey Jin; Doan, Ngan; Said, Jonathan W; Chu, Peiguo; Mayakonda, Anand; Thomas, Tom; Forscher, Charles; Baloglu, Erkan; Shacham, Sharon; Rajalingam, Raja; Koeffler, H Phillip

    2016-05-01

    Ewing sarcoma (EWS) is an aggressive bone malignancy that mainly affects children and young adults. The mechanisms by which EWS (EWSR1) fusion genes drive the disease are not fully understood. CRM1 (XPO1) traffics proteins from the nucleus, including tumor suppressors and growth factors, and is overexpressed in many cancers. A small-molecule inhibitor of CRM1, KPT-330, has shown therapeutic promise, but has yet to be investigated in the context of EWS. In this study, we demonstrate that CRM1 is also highly expressed in EWS. shRNA-mediated or pharmacologic inhibition of CRM1 in EWS cells dramatically decreased cell growth while inducing apoptosis, cell-cycle arrest, and protein expression alterations to several cancer-related factors. Interestingly, silencing of CRM1 markedly reduced EWS-FLI1 fusion protein expression at the posttranscriptional level and upregulated the expression of the well-established EWS-FLI1 target gene, insulin-like growth factor binding protein 3 (IGFBP3), which inhibits IGF-1. Accordingly, KPT-330 treatment attenuated IGF-1-induced activation of the IGF-1R/AKT pathway. Furthermore, knockdown of IGFBP3 increased cell growth and rescued the inhibitory effects on IGF-1 signaling triggered by CRM1 inhibition. Finally, treatment of EWS cells with a combination of KPT-330 and the IGF-1R inhibitor, linsitinib, synergistically decreased cell proliferation both in vitro and in vivo Taken together, these findings provide a strong rationale for investigating the efficacy of combinatorial inhibition of CRM1 and IGF-1R for the treatment of EWS. Cancer Res; 76(9); 2687-97. ©2016 AACR. PMID:26956669

  5. Targeting Tumor Initiating Cells through Inhibition of Cancer Testis Antigens and Notch Signaling: A Hypothesis.

    Science.gov (United States)

    Colombo, Michela; Mirandola, Leonardo; Reidy, Adair; Suvorava, Natallia; Konala, Venu; Chiaramonte, Raffaella; Grizzi, Fabio; Rahman, Rakhshanda Layeequr; Jenkins, Marjorie R; Nugyen, Diane D; Dalhbeck, Scott; Cobos, Everardo; Figueroa, Jose A; Chiriva-Internati, Maurizio

    2015-03-01

    Tumor initiating cells (TICs) differ from normal stem cells (SCs) in their ability to initiate tumorigenesis, invasive growth, metastasis and the acquisition of chemo and/or radio-resistance. Over the past years, several studies have indicated the potential role of the Notch system as a key regulator of cellular stemness and tumor development. Furthermore, the expression of cancer testis antigens (CTA) in TICs, and their role in SC differentiation and biology, has become an important area of investigation. Here, we propose a model in which CTA expression and Notch signaling interacts to maintain the sustainability of self-replicating tumor populations, ultimately leading to the development of metastasis, drug resistance and cancer progression. We hypothesize that Notch-CTA interactions in TICs offer a novel opportunity for meaningful therapeutic interventions in cancer. PMID:25901861

  6. RAG-mediated DNA double-strand breaks activate a cell type-specific checkpoint to inhibit pre-B cell receptor signals.

    Science.gov (United States)

    Bednarski, Jeffrey J; Pandey, Ruchi; Schulte, Emily; White, Lynn S; Chen, Bo-Ruei; Sandoval, Gabriel J; Kohyama, Masako; Haldar, Malay; Nickless, Andrew; Trott, Amanda; Cheng, Genhong; Murphy, Kenneth M; Bassing, Craig H; Payton, Jacqueline E; Sleckman, Barry P

    2016-02-01

    DNA double-strand breaks (DSBs) activate a canonical DNA damage response, including highly conserved cell cycle checkpoint pathways that prevent cells with DSBs from progressing through the cell cycle. In developing B cells, pre-B cell receptor (pre-BCR) signals initiate immunoglobulin light (Igl) chain gene assembly, leading to RAG-mediated DNA DSBs. The pre-BCR also promotes cell cycle entry, which could cause aberrant DSB repair and genome instability in pre-B cells. Here, we show that RAG DSBs inhibit pre-BCR signals through the ATM- and NF-κB2-dependent induction of SPIC, a hematopoietic-specific transcriptional repressor. SPIC inhibits expression of the SYK tyrosine kinase and BLNK adaptor, resulting in suppression of pre-BCR signaling. This regulatory circuit prevents the pre-BCR from inducing additional Igl chain gene rearrangements and driving pre-B cells with RAG DSBs into cycle. We propose that pre-B cells toggle between pre-BCR signals and a RAG DSB-dependent checkpoint to maintain genome stability while iteratively assembling Igl chain genes. PMID:26834154

  7. miR-20a inhibits TCR-mediated signaling and cytokine production in human naive CD4+ T cells.

    Directory of Open Access Journals (Sweden)

    Amarendra V Reddycherla

    Full Text Available Upon TCR stimulation by peptide-MHC complexes, CD4+ T cells undergo activation and proliferation. This process will ultimately culminate in T-cell differentiation and the acquisition of effector functions. The production of specific cytokines by differentiated CD4+ T cells is crucial for the generation of the appropriate immune response. Altered CD4+ T-cell activation and cytokine production result in chronic inflammatory conditions and autoimmune disorders. miRNAs have been shown to be important regulators of T-cell biology. In this study, we have focused our investigation on miR-20a, a member of the miR-17-92 cluster, whose expression is decreased in patients suffering from multiple sclerosis. We have found that miR-20a is rapidly induced upon TCR-triggering in primary human naïve CD4+ T cells and that its transcription is regulated in a Erk-, NF-κB-, and Ca++-dependent manner. We have further shown that overexpression of miR-20a inhibits TCR-mediated signaling but not the proliferation of primary human naïve CD4+ T cells. However, miR-20a overexpression strongly suppresses IL-10 secretion and moderately decreases IL-2, IL-6 and IL8 production, which are crucial regulators of inflammatory responses. Our study suggests that miR-20a is a new player in the regulation of TCR signaling strength and cytokine production.

  8. Resveratrol inhibits breast cancer stem-like cells and induces autophagy via suppressing Wnt/β-catenin signaling pathway.

    Directory of Open Access Journals (Sweden)

    Yujie Fu

    Full Text Available Resveratrol, a natural polyphenolic compound, is abundantly found in plant foods and has been extensively studied for its anti-cancer properties. Given the important role of CSCs (Cancer Stem Cells in breast tumorigenesis and progression, it is worth investigating the effects of resveratrol on CSCs. The article is an attempt to investigate the effects of resveratrol on breast CSCs. Resveratrol significantly inhibits the proliferation of BCSCs (breast cancer stem-like cells isolated from MCF-7 and SUM159, and decreased the percentage of BCSCs population, consequently reduced the size and number of mammospheres in non-adherent spherical clusters. Accordingly, the injection of resveratrol (100 mg/kg/d in NOD/SCID (nonobese diabetic/severe combined immunodeficient mice effectively inhibited the growth of xenograft tumors and reduced BCSC population in tumor cells. After the reimplantation of primary tumor cells into the secondary mice for 30 d, all 6 control inoculations produced tumors, while tumor cells derived from resveratrol-treated mice only caused 1 tumor of 6 inoculations. Further studies by TEM (Transmission electron microscopy analysis, GFP-LC3-II puncta formation assay and western blot for LC3-II, Beclin1 and Atg 7, showed that resveratrol induces autophagy in BCSCs. Moreover, resveratrol suppresses Wnt/β-catenin signaling pathway in BCSCs; over-expression of β-catenin by transfecting the plasmid markedly reduced resveratrol-induced cytotoxicity and autophagy in BCSCs. Our findings indicated that resveratrol inhibits BCSCs and induces autophagy via suppressing Wnt/β-catenin signaling pathway.

  9. Leptin interferes with 3',5'-Cyclic Adenosine Monophosphate (cAMP signaling to inhibit steroidogenesis in human granulosa cells

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    HoYuen Basil

    2009-10-01

    Full Text Available Abstract Background Obesity has been linked to an increased risk of female infertility. Leptin, an adipocytokine which is elevated during obesity, may influence gonadal function through modulating steroidogenesis in granulosa cells. Methods The effect of leptin on progesterone production in simian virus 40 immortalized granulosa (SVOG cells was examined by Enzyme linked immunosorbent assay (ELISA. The effect of leptin on the expression of the steroidogenic enzymes (StAR, P450scc, 3betaHSD in SVOG cells was examined by real-time PCR and Western blotting. The mRNA expression of leptin receptor isoforms in SVOG cells were examined by using PCR. SVOG cells were co-treated with leptin and specific pharmacological inhibitors to identify the signaling pathways involved in leptin-reduced progesterone production. Silencing RNA against leptin receptor was used to determine that the inhibition of leptin on cAMP-induced steroidogenesis acts in a leptin receptor-dependent manner. Results and Conclusion In the present study, we investigated the cellular mechanisms underlying leptin-regulated steroidogenesis in human granulosa cells. We show that leptin inhibits 8-bromo cAMP-stimulated progesterone production in a concentration-dependent manner. Furthermore, we show that leptin inhibits expression of the cAMP-stimulated steroidogenic acute regulatory (StAR protein, the rate limiting de novo protein in progesterone synthesis. Leptin induces the activation of ERK1/2, p38 and JNK but only the ERK1/2 (PD98059 and p38 (SB203580 inhibitors attenuate the leptin-induced inhibition of cAMP-stimulated StAR protein expression and progesterone production. These data suggest that the leptin-induced MAPK signal transduction pathway interferes with cAMP/PKA-stimulated steroidogenesis in human granulosa cells. Moreover, siRNA mediated knock-down of the endogenous leptin receptor attenuates the effect of leptin on cAMP-induced StAR protein expression and progesterone

  10. Thioridazine inhibits gene expression control of the cell wall signaling pathway (CWI) in the human pathogenic fungus Paracoccidioides brasiliensis.

    Science.gov (United States)

    Jabes, Daniela Leite; de Freitas Oliveira, Ana Claudia; Alencar, Valquíria Campos; Menegidio, Fabiano Bezerra; Reno, Débora Liliane Souza; Santos, Daiene Souza; Barbosa, David Aciole; Vilas Boas, Renata Ozelami; de Oliveira Rodrigues Cunha, Rodrigo Luiz; Rodrigues, Tiago; Costa de Oliveira, Regina; Nunes, Luiz R

    2016-06-01

    Paracoccidioides brasiliensis is a thermodimorphic fungus associated with paracoccidioidomycosis (PCM), the most common systemic mycosis in Latin America. PCM treatment involves a long-term chemotherapeutic approach and relapses occur at an alarming frequency. Moreover, the emergence of strains with increased drug-resistance phenotypes puts constant pressure on the necessity to develop new alternatives to treat systemic mycoses. In this work, we show that the phenothiazine (PTZ) derivative thioridazine (TR) inhibits in vitro growth of P. brasiliensis yeasts at micromolar concentrations. We employed microarray hybridization to examine how TR affects gene expression in this fungus, identifying ~1800 genes that were modulated in response to this drug. Dataset evaluation showed that TR inhibits the expression of genes that control the onset of the cell wall integrity (CWI) response, hampering production of all major structural polysaccharides of the fungal cell wall (chitin, α-glucan and β-glucan). Although TR and other PTZs have been shown to display antimicrobial activity by various mechanisms, inhibition of CWI signaling has not yet been reported for these drugs. Thus, TR may provide a novel approach to treat fungal infections by targeting cell wall biogenesis. PMID:26956010

  11. Basal-subtype and MEK-Pl3K feedback signaling determine susceptibility of breast cancer cells to MEK inhibition

    Energy Technology Data Exchange (ETDEWEB)

    Mirzoeva, Olga K.; Das, Debopriya; Heiser, Laura M.; Bhattacharya, Sanchita; Siwak, Doris; Gendelman, Rina; Bayani, Nora; Wang, Nicholas J.; Neve, Richard M.; Knight, Zachary; Feiler, Heidi S.; Gascard, Philippe; Parvin, Bahram; Spellman, Paul T.; Shokat, Kevan M.; Wyrobek, Andrew J.; Bissell, Mina J.; McCormick, Frank; Kuo, Wen-Lin; Mills, Gordon B.; Gray, Joe W.; Korn, W. Michael

    2009-01-23

    Specific inhibitors of MEK have been developed that efficiently inhibit the oncogenic RAF-MEK-ERK pathway. We employed a systems-based approach to identify breast cancer subtypes particularly susceptible to MEK inhibitors and to understand molecular mechanisms conferring resistance to such compounds. Basal-type breast cancer cells were found to be particularly susceptible to growth-inhibition by small-molecule MEK inhibitors. Activation of the PI3 kinase pathway in response to MEK inhibition through a negative MEK-EGFR-PI3 kinase feedback loop was found to limit efficacy. Interruption of this feedback mechanism by targeting MEK and PI3 kinase produced synergistic effects, including induction of apoptosis and, in some cell lines, cell cycle arrest and protection from apoptosis induced by proapoptotic agents. These findings enhance our understanding of the interconnectivity of oncogenic signal transduction circuits and have implications for the design of future clinical trials of MEK inhibitors in breast cancer by guiding patient selection and suggesting rational combination therapies.

  12. 5-Azacytidine suppresses the proliferation of pancreatic cancer cells by inhibiting the Wnt/β-catenin signaling pathway.

    Science.gov (United States)

    Zhang, H; Zhou, W C; Li, X; Meng, W B; Zhang, L; Zhu, X L; Zhu, K X; Bai, Z T; Yan, J; Liu, T; Xu, X C; Li, Y M

    2014-01-01

    5-Azacytidine has been shown to be an effective anti-pancreatic cancer drug, but the mechanism remains unknown. In the current study, we explored the effect of 5-azacytidine on abnormal activation of the Wnt-β-catenin signaling pathway in pancreatic cancer cells. The human pancreatic cancer cell line Bxpc-3 was treated with different concentrations of 5-azacytidine for various times. The proliferation and early apoptosis of the cells were evaluated using the CCK8 method and flow cytometry, respectively. mRNA and protein expression of β-catenin, c-myc, and cyclinD1 were detected using real-time fluorescent quantitative polymerase chain reaction and Western blot analysis, respectively. The proliferation of Bxpc-3 cells was suppressed by 5-azacytidine. The early apoptosis of the cells was significantly enhanced over time and with increasing drug concentrations. The expression of β-catenin, c-myc, and cyclinD1 were down-regulated, showing significant differences between different concentrations and treatment times (P < 0.05). 5-Azacytidine suppressed the proliferation of pancreatic cancer cells by inhibiting the Wnt/β-catenin signaling pathway, particularly the expression of β-catenin, c-myc, and cyclinD1. This study may provide a new potential strategy for diagnosing and treating pancreatic cancer. PMID:25061731

  13. Cardiotoxin III suppresses MDA-MB-231 cell metastasis through the inhibition of EGF/EGFR-mediated signaling pathway.

    Science.gov (United States)

    Tsai, Pei-Chien; Hsieh, Chi-Ying; Chiu, Chien-Chih; Wang, Chih-Kuang; Chang, Long-Sen; Lin, Shinne-Ren

    2012-10-01

    Cardiotoxin III (CTX III), a basic polypeptide isolated from Naja naja atra venom, has been shown to exhibit anticancer activity. Epidermal growth factor (EGF) and its receptor, EGFR, play roles in cancer metastasis in various tumors. We use EGF as a metastatic inducer of MDA-MB-231 cells to investigate the effect of CTX III on cell migration. CTX III inhibited the EGF-induced activation of matrix metalloproteinase-9 (MMP-9), and further suppressed cell invasion and migration without obvious cellular cytotoxicity. CTX III suppressed EGF-induced nuclear factor-kappaB (NF-κB) nuclear translocation and also abrogated the EGF-induced phosphorylation of EGFR, phosphatidylinositol 3-kinase (PI3K)/Akt, and extracellular regulated kinase (ERK)1/2. In addition, CTX III similar to wortmannin (a PI3K inhibitor) and U0126 (an up-stream kinase regulating ERK1/2 inhibitor) attenuated cell migration and invasion induced by EGF. Furthermore, the EGFR inhibitor AG1478 inhibited EGF-induced MMP-9 expression, cell migration and invasion, as well as the activation of ERK1/2 and PI3K/Akt, suggesting that ERK1/2 and PI3K/Akt activation occur downstream of EGFR activation. These findings suggest that CTX III inhibited the EGF-induced invasion and migration of MDA-MB-231 cells via EGFR-dependent PI3K/Akt, ERK1/2, and NF-κB signaling, leading to the down-regulation of MMP-9 expression. These results provide a novel mechanism to explain the role of CTX III as a potent anti-metastatic agent in MDA-MB-231 cells.

  14. Silibinin inhibits fibronectin induced motility, invasiveness and survival in human prostate carcinoma PC3 cells via targeting integrin signaling.

    Science.gov (United States)

    Deep, Gagan; Kumar, Rahul; Jain, Anil K; Agarwal, Chapla; Agarwal, Rajesh

    2014-10-01

    Prostate cancer (PCA) is the 2nd leading cause of cancer-related deaths among men in the United States. Preventing or inhibiting metastasis-related events through non-toxic agents could be a useful approach for lowering high mortality among PCA patients. We have earlier reported that natural flavonoid silibinin possesses strong anti-metastatic efficacy against PCA however, mechanism/s of its action still remains largely unknown. One of the major events during metastasis is the replacement of cell-cell interaction with integrins-based cell-matrix interaction that controls motility, invasiveness and survival of cancer cells. Accordingly, here we examined silibinin effect on advanced human PCA PC3 cells' interaction with extracellular matrix component fibronectin. Silibinin (50-200 μM) treatment significantly decreased the fibronectin (5 μg/ml)-induced motile morphology via targeting actin cytoskeleton organization in PC3 cells. Silibinin also decreased the fibronectin-induced cell proliferation and motility but significantly increased cell death in PC3 cells. Silibinin also inhibited the PC3 cells invasiveness in Transwell invasion assays with fibronectin or cancer associated fibroblasts (CAFs) serving as chemoattractant. Importantly, PC3-luc cells cultured on fibronectin showed rapid dissemination and localized in lungs following tail vein injection in athymic male nude mice; however, in silibinin-treated PC3-luc cells, dissemination and lung localization was largely compromised. Molecular analyses revealed that silibinin treatment modulated the fibronectin-induced expression of integrins (α5, αV, β1 and β3), actin-remodeling (FAK, Src, GTPases, ARP2 and cortactin), apoptosis (cPARP and cleaved caspase 3), EMT (E-cadherin and β-catenin), and cell survival (survivin and Akt) related signaling molecules in PC3 cells. Furthermore, PC3-xenograft tissue analyses confirmed the inhibitory effect of silibinin on fibronectin and integrins expression. Together, these

  15. 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.

  16. 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

  17. Butein Inhibits Angiogenesis of Human Endothelial Progenitor Cells via the Translation Dependent Signaling Pathway

    Directory of Open Access Journals (Sweden)

    Ching-Hu Chung

    2013-01-01

    Full Text Available Compelling evidence indicates that bone marrow-derived endothelial progenitor cells (EPCs can contribute to postnatal neovascularization and tumor angiogenesis. EPCs have been shown to play a “catalytic” role in metastatic progression by mediating the angiogenic switch. Understanding the pharmacological functions and molecular targets of natural products is critical for drug development. Butein, a natural chalcone derivative, has been reported to exert potent anticancer activity. However, the antiangiogenic activity of butein has not been addressed. In this study, we found that butein inhibited serum- and vascular endothelial growth factor- (VEGF- induced cell proliferation, migration, and tube formation of human EPCs in a concentration dependent manner without cytotoxic effect. Furthermore, butein markedly abrogated VEGF-induced vessels sprouting from aortic rings and suppressed microvessel formation in the Matrigel implant assay in vivo. In addition, butein concentration-dependently repressed the phosphorylation of Akt, mTOR, and the major downstream effectors, p70S6K, 4E-BP1, and eIF4E in EPCs. Taken together, our results demonstrate for the first time that butein exhibits the antiangiogenic effect both in vitro and in vivo by targeting the translational machinery. Butein is a promising angiogenesis inhibitor with the potential for treatment of cancer and other angiogenesis-related diseases.

  18. Resveratrol inhibits invasion and metastasis of colorectal cancer cells via MALAT1 mediated Wnt/β-catenin signal pathway.

    Directory of Open Access Journals (Sweden)

    Qing Ji

    Full Text Available Resveratrol, extracted from Chinese herbal medicine Polygonum cuspidatum, is known to inhibit invasion and metastasis of human colorectal cancer (CRC, in which long non-coding Metastasis Associated Lung Adenocarcinoma Transcript 1 (RNA-MALAT1 also plays an important role. Using MALAT1 lentiviral shRNA and over-expression constructs in CRC derived cell lines, LoVo and HCT116, we demonstrated that the anti-tumor effects of resveratrol on CRC are through inhibiting Wnt/β-catenin signaling, thus the expression of its target genes such as c-Myc, MMP-7, as well as the expression of MALAT1. In detail, resveratrol down-regulates MALAT1, resulting in decreased nuclear localization of β-catenin thus attenuated Wnt/β-catenin signaling, which leads to the inhibition of CRC invasion and metastasis. This finding of ours surely provides important pre-clinical evidence supporting future use of resveratrol in prevention and treatment of CRC.

  19. Neuropeptide Y1 receptor inhibits cell growth through inactivating mitogen-activated protein kinase signal pathway in human hepatocellular carcinoma.

    Science.gov (United States)

    Lv, Xiufang; Zhao, Fengbo; Huo, Xisong; Tang, Weidong; Hu, Baoying; Gong, Xiu; Yang, Juan; Shen, Qiujin; Qin, Wenxin

    2016-07-01

    Hepatocellular carcinoma (HCC) is one of the most common cancers, and its incidence is increasing worldwide. Neuropeptide Y (NPY) broadly expressed in the central and peripheral nervous system. It participates in multiple physiological and pathological processes through specific receptors. Evidences are accumulating that NPY is involved in development and progression in neuro- or endocrine-related cancers. However, little is known about the potential roles and underlying mechanisms of NPY receptors in HCC. In this study, we analyzed the expression of NPY receptors by real-time polymerase chain reaction, Western blot, and immunohistochemical staining. Correlation between NPY1R levels and clinicopathological characteristics, and survival of HCC patients were explored, respectively. Cell proliferation was researched by CCK-8 in vitro, and tumor growth was studied by nude mice xenografts in vivo. We found that mRNA and protein level of NPY receptor Y1 subtype (NPY1R) significantly decreased in HCC tissues. Low expression of NPY1R closely correlated with poor prognosis in HCC patients. Proliferation of HCC cells was significantly inhibited by recombinant NPY protein in vitro. This inhibitory effect could be blocked by selected NPY1R antagonist BIBP3226. Furthermore, overexpression of NPY1R could significantly inhibit HCC cell proliferation. Knockdown of NPY1R promoted cell multiplication in vitro and increased tumorigenicity and tumor growth in vivo. NPY1R was found to participate in the inhibition of cell proliferation via inactivating mitogen-activated protein kinase signal pathway in HCC cells. Collectively, NPY1R plays an inhibitory role in tumor growth and may be a promising therapeutic target for HCC. PMID:27262566

  20. Concurrent MEK and autophagy inhibition is required to restore cell death associated danger-signalling in Vemurafenib-resistant melanoma cells.

    Science.gov (United States)

    Martin, S; Dudek-Perić, A M; Maes, H; Garg, A D; Gabrysiak, M; Demirsoy, S; Swinnen, J V; Agostinis, P

    2015-02-01

    Vemurafenib (PLX4032), an inhibitor of BRAF(V600E), has demonstrated significant clinical anti-melanoma effects. However, the majority of treated patients develop resistance, due to a variety of molecular mechanisms including MAPK reactivation through MEK. The induction of a cancer cell death modality associated with danger-signalling resulting in surface mobilization of crucial damage-associated-molecular-patterns (DAMPs), e.g. calreticulin (CRT) and heat shock protein-90 (HSP90), from dying cells, is emerging to be crucial for therapeutic success. Both cell death and danger-signalling are modulated by autophagy, a key adaptation mechanism stimulated during melanoma progression. However, whether melanoma cell death induced by MAPK inhibition is associated with danger-signalling, and the reliance of these mechanisms on autophagy, has not yet been scrutinized. Using a panel of isogenic PLX4032-sensitive and resistant melanoma cell lines we show that PLX4032-induced caspase-dependent cell death and DAMPs exposure in the drug-sensitive cells, but failed to do so in the drug-resistant cells, displaying heightened MEK activation. MEK inhibitor, U0126, treatment sensitized PLX4032-resistant cells to death and re-established their danger-signalling capacity. Only melanoma cells exposing death-induced danger-signals were phagocytosed and induced DC maturation. Although the PLX4032-resistant melanoma cells displayed higher basal and drug-induced autophagy, compromising autophagy, pharmacologically or by ATG5 knockdown, was insufficient to re-establish their PLX4032 sensitivity. Interestingly, autophagy abrogation was particularly efficacious in boosting cell death and ecto-CRT/ecto-HSP90 in PLX4032-resistant cells upon blockage of MEK hyper-activation by U0126. Thus combination of MEK inhibitors with autophagy blockers may represent a novel treatment regime to increase both cell death and danger-signalling in Vemurafenib-resistant metastatic melanoma.

  1. Turmeric and Chinese goldthread synergistically inhibit prostate cancer cell proliferation and NF-kB signaling

    Directory of Open Access Journals (Sweden)

    Yi Zhao

    2014-07-01

    Full Text Available Background: Pre-clinical studies using bioactive compounds from botanicals appear to offer some protection against cancer. Research using single bioactives contributes greatly to our understanding of their mechanism of action, but in vitro studies demand concentrations that are higher than achievable in humans (µM. However, maintaining these bioactives in the presence of other compounds originally derived from the food or extract of origin may synergistically lower the bioactive dose so translatability becomes feasible. The objective of this study was to determine if bio-efficacy of phytonutrients can be enhanced when used in combination even at doses that are ineffective for any compound when used in isolation. Methods: The anti-proliferative and molecular effects of herbs (turmeric and Chinese goldthread and their bioactives (curcumin and ar-turmerone, berberine and coptisine, respectively were determined in isolation and in combination. Using CWR22Rv1 and HEK293 cells, cell proliferation (as assessed by the MTT assay and NF-κB promoter activity (using a luciferase reporter construct were evaluated and synergy of action was assessed by the ChouTalalay method utilizing CompuSyn® software. Results: Turmeric and Chinese goldthread act synergistically (combination index<1 when inhibiting cell proliferation with all cell lines tested. The synergy of action of combinations of companion bioactives from the same herb (i.e., curcumin/ar-turmerone and berberine/coptisine and bioactives from different herbs (i.e., curcumin/berberine help to explain why turmeric and Chinese goldthread are more effective than their major bioactives in isolation. At the molecule level, curcumin+ar-turmerone and curcumin+coptisine synergistically attenuated TNFα- stimulated NF-κB promoter activity. Even compounds with poor efficacy become more biologically active in the presence of companion compounds. Importantly, the effects of combining any two bioactives or herbal

  2. Fasudil inhibits LPS-induced migration of retinal microglial cells via regulating p38-MAPK signaling pathway

    Science.gov (United States)

    Xu, Fan; Xu, Yue; Zhu, Liqiong; Rao, Pinhong; Wen, Jiamin; Sang, Yunyun; Shang, Fu

    2016-01-01

    Purpose To investigate the effect and possible molecular mechanisms of fasudil on retinal microglial (RMG) cell migration. Methods Primary cultured RMG cells were incubated with lipopolysaccharide (LPS), fasudil, and/or SB203580 (a p38 inhibitor). RMG cell motility was determined with the scratch wound assay and the Transwell migration assay. The phosphorylation of p38 and levels of matrix metalloproteinase 2 (MMP-2) and MMP-9 were measured with western blot. Results In the scratch-induced migration assay, as well as in the Transwell migration assay, the results indicated that LPS stimulated the migratory potential of RMG cells and fasudil significantly reduced LPS-stimulated RMG cell migration in a concentration-dependent manner. However, fasudil had no effect on RMG cell migration in the absence of LPS stimulation. Moreover, fasudil reduced the level of phosphor-p38 mitogen-activated protein kinase (p-p38-MAPK) in a concentration-dependent manner, without effects on the levels of phospho-p44/42 (p-ERK1/2) and phospho-c-Jun N-terminal kinase (p-JNK). Cotreatment with SB203580 (a p38 inhibitor) and fasudil resulted in the synergistic reduction of MMP-2, MMP-9, and p-p38-MAPK, as well as a reduction in the LPS-stimulated migration capabilities of the RMG cells, suggesting fasudil suppresses the LPS-stimulated migration of RMG cells via directly downregulating the p38-MAPK signaling pathway. Conclusions Our studies indicated that fasudil inhibited LPS-stimulated RMG cell migration via suppression of the p38-MAPK signaling pathway. PMID:27441000

  3. TRAF6 inhibits proangiogenic signals in endothelial cells and regulates the expression of vascular endothelial growth factor

    Energy Technology Data Exchange (ETDEWEB)

    Bruneau, Sarah; Datta, Dipak; Flaxenburg, Jesse A.; Pal, Soumitro [Transplantation Research Center, Division of Nephrology, Department of Medicine, Children' s Hospital Boston, Boston, MA (United States); Department of Pediatrics, Harvard Medical School, Boston, MA (United States); Briscoe, David M., E-mail: david.briscoe@childrens.harvard.edu [Transplantation Research Center, Division of Nephrology, Department of Medicine, Children' s Hospital Boston, Boston, MA (United States); Department of Pediatrics, Harvard Medical School, Boston, MA (United States)

    2012-03-02

    Highlights: Black-Right-Pointing-Pointer TNF-receptor associated factors (TRAFs) function in the angiogenesis response. Black-Right-Pointing-Pointer TRAF6 regulates basal and inducible expression of VEGF in endothelial cells (EC). Black-Right-Pointing-Pointer TRAF6 is an endogenous inhibitor of EC proliferation and migration in EC. Black-Right-Pointing-Pointer TRAF6 inhibits VEGF expression in part via its ability to regulate Src signaling. -- Abstract: TNF-family molecules induce the expression Vascular Endothelial Growth Factor (VEGF) in endothelial cells (EC) and elicit signaling responses that result in angiogenesis. However, the role of TNF-receptor associated factors (TRAFs) as upstream regulators of VEGF expression or as mediators of angiogenesis is not known. In this study, HUVEC were cotransfected with a full-length VEGF promoter-luciferase construct and siRNAs to TRAF 1, -2, -3, -5, -6, and promoter activity was measured. Paradoxically, rather than inhibiting VEGF expression, we found that knockdown of TRAF6 resulted in a 4-6-fold increase in basal VEGF promoter activity compared to control siRNA-transfected EC (P < 0.0001). In addition, knockdown of TRAF 1, -2, -3 or -5 resulted in a slight increase or no change in VEGF promoter activation. Using [{sup 3}H]thymidine incorporation assays as well as the in vitro wound healing assay, we also found that basal rates of EC proliferation and migration were increased following TRAF6 knockdown; and this response was inhibited by the addition of a blocking anti-VEGF antibody into cell cultures. Using a limited protein array to gain insight into TRAF6-dependent intermediary signaling responses, we observed that TRAF6 knockdown resulted in an increase in the activity of Src family kinases. In addition, we found that treatment with AZD-0530, a pharmacological Src inhibitor, reduced the regulatory effect of TRAF6 knockdown on VEGF promoter activity. Collectively, these findings define a novel pro-angiogenic signaling

  4. Inhibition of STAT3, FAK and Src mediated signaling reduces cancer stem cell load, tumorigenic potential and metastasis in breast cancer.

    Science.gov (United States)

    Thakur, Ravi; Trivedi, Rachana; Rastogi, Namrata; Singh, Manisha; Mishra, Durga Prasad

    2015-01-01

    Cancer stem cells (CSCs) are responsible for aggressive tumor growth, metastasis and therapy resistance. In this study, we evaluated the effects of Shikonin (Shk) on breast cancer and found its anti-CSC potential. Shk treatment decreased the expression of various epithelial to mesenchymal transition (EMT) and CSC associated markers. Kinase profiling array and western blot analysis indicated that Shk inhibits STAT3, FAK and Src activation. Inhibition of these signaling proteins using standard inhibitors revealed that STAT3 inhibition affected CSCs properties more significantly than FAK or Src inhibition. We observed a significant decrease in cell migration upon FAK and Src inhibition and decrease in invasion upon inhibition of STAT3, FAK and Src. Combined inhibition of STAT3 with Src or FAK reduced the mammosphere formation, migration and invasion more significantly than the individual inhibitions. These observations indicated that the anti-breast cancer properties of Shk are due to its potential to inhibit multiple signaling proteins. Shk also reduced the activation and expression of STAT3, FAK and Src in vivo and reduced tumorigenicity, growth and metastasis of 4T1 cells. Collectively, this study underscores the translational relevance of using a single inhibitor (Shk) for compromising multiple tumor-associated signaling pathways to check cancer metastasis and stem cell load. PMID:25973915

  5. Metformin-mediated growth inhibition involves suppression of the IGF-I receptor signalling pathway in human pancreatic cancer cells

    International Nuclear Information System (INIS)

    Epidemiological studies have shown direct associations between type 2 diabetes and obesity, both conditions associated with hyperglycaemia and hyperinsulinemia, and the risk of pancreatic cancer. Up to 80% of pancreatic cancer patients present with either new-onset type 2 diabetes or impaired glucose tolerance at the time of diagnosis. Recent population studies indicate that the incidence of pancreatic cancer is reduced among diabetics taking metformin. In this study, the effects of exposure of pancreatic cancer cells to high glucose levels on their growth and response to metformin were investigated. The human pancreatic cancer cell lines AsPC-1, BxPC-3, PANC-1 and MIAPaCa-2 were grown in normal (5 mM) or high (25 mM) glucose conditions, with or without metformin. The influence by metformin on proliferation, apoptosis and the AMPK and IGF-IR signalling pathways were evaluated in vitro. Metformin significantly reduced the proliferation of pancreatic cancer cells under normal glucose conditions. Hyperglycaemia however, protected against the metformin-induced growth inhibition. The anti-proliferative actions of metformin were associated with an activation of AMP-activated protein kinase AMPKThr172 together with an inhibition of the insulin/insulin-like growth factor-I (IGF-I) receptor activation and downstream signalling mediators IRS-1 and phosphorylated Akt. Furthermore, exposure to metformin during normal glucose conditions led to increased apoptosis as measured by poly(ADP-ribose) polymerase (PARP) cleavage. In contrast, exposure to high glucose levels promoted a more robust IGF-I response and Akt activation which correlated to stimulated AMPKSer485 phosphorylation and impaired AMPKThr172 phosphorylation, resulting in reduced anti-proliferative and apoptotic effects by metformin. Our results indicate that metformin has direct anti-tumour activities in pancreatic cancer cells involving AMPKThr172 activation and suppression of the insulin/IGF signalling pathways

  6. A therapeutic anti-CD4 monoclonal antibody inhibits T cell receptor signal transduction in mouse autoimmune cardiomyopathy

    Institute of Scientific and Technical Information of China (English)

    WANG Zhao-hui; LIAO Yu-hua; YUAN Jing; ZHANG Li; WANG Min; ZHANG Jing-hui; LIU Zhong-ping; DONG Ji-hua

    2007-01-01

    Background T cell immune abnormalities in patients with dilated cardiomyopathy (DCM) has been intensively studied over the past 10 years. Our previous study has suggested that immunization of mice with the peptides derived from human adenine nucleotide translocator (ANT) result in the production of autoantibodies against the ANT and histopathological changes similar to those in human DCM. The ANT peptides can induce autoimmune cardiomyopathy like DCM in Balb/c mice. In this study we aimed to focus on the molecular mechanism of T cells in the autoimmune cardiomyopathy mouse model by detecting the expression of the two T cell signaling molecules.Methods The ANT peptides were used to cause autoimmune cardiomyopathy in Balb/c mice. Anti-L3T4 or rat anti-mouse IgG was administered to the mice (n=6 in each group) simultaneously immunized with ANT. ELISA analysis was used to detect autoantibodies against the ANT peptides and the percentages of interferon-Y and interleukin-4 producing cells among splenic CD4+ lymphocytes was determined by using flow cytometry analysis. The expression of CD45 in spleen T cells was determined by immunohistochemistry and the mRNAs of T cell signaling molecules were detected by real-time PCR.Results Treatment of ANT immunized Balb/c mice with anti-CD4 mAb caused a reduction in the gene expression of P56lck and Zap-70 and a lower level of CD45 expression by spleen T cells. Aiso, a reverse of the Th1/Th2 ratio that results in the reduced production of antibodies against ANT was found in the anti-CD4 monoclonal antibodies (mAb)group. Whereas irrelevant antibody (rat anti-mouse IgG) did not suppress T cell signaling molecules nor inhibit CD45 expression, and control-antibody mice did not show any significant differences compared with the DCM group.Conclusion The results show that anti-CD4 mAb is a powerful inhibitor of the early initiating events of T cell receptor(TCR) signal transduction in mouse autoimmune dilated cardiomyopathy.

  7. Inhibition of Wnt/β-catenin signaling by dexamethasone promotes adipocyte differentiation in mesenchymal progenitor cells, ROB-C26.

    Science.gov (United States)

    Naito, Masako; Omoteyama, Kazuki; Mikami, Yoshikazu; Takahashi, Tomihisa; Takagi, Minoru

    2012-12-01

    Dexamethasone (Dex) stimulates the differentiation of mesenchymal progenitor cells into adipocytes and osteoblasts. However, the mechanisms underlying Dex-induced differentiation have not been clearly elucidated. We examined the effect of Dex on the expression and activity of Wnt/β-catenin signal-related molecules in a clonal mesenchymal progenitor cell line, ROB-C26 (C26). Dex induced the mRNA expression of Wnt antagonists, dickkopf-1 (Dkk-1), and Wnt inhibitory factor (WIF)-1. Immunocytochemical analysis showed that the downregulation of β-catenin protein expression by Dex occured concomitantly with the increased expression of the PPARγ protein. Dex decreased phosphorylation of Ser9-GSK3β and expression of active β-catenin protein. To examine the effects of Dex on Wnt/β-catenin activity, we used immunocytochemistry to analyze TCF/LEF-mediated transcription during Dex-induced adipogenesis in Wnt indicator (TOPEGFP) C26 cells. Our results demonstrated that Dex repressed TCF/LEF-mediated transcription, but induced adipocyte differentiation. Treatment with a GSK3β inhibitor attenuated Dex-induced inhibition of TCF/LEF-mediated transcriptional activity, but suppressed Dex-induced adipocyte differentiation, indicating that adipocyte differentiation and inhibition of Wnt/β-catenin activity by Dex are mediated by GSK3β activity. Furthermore, β-catenin knockdown not only suppressed Dex-induced ALP-positive osteoblasts differentiation but also promoted Dex-induced adipocytes differentiation. These results suggest that inhibition of β-catenin expression by Dex promotes the differentiation of mesenchymal progenitor cells into adipocytes. PMID:22886144

  8. Inhibition of astroglial cell proliferation by alcohols: interference with the protein kinase C-phospholipase D signaling pathway.

    Science.gov (United States)

    Kötter, K; Jin, S; Klein, J

    2000-12-01

    Ethanol inhibits astroglial cell proliferation, an effect that may contribute to the development of alcoholic embryopathy in humans. In the present study, we investigated inhibitory effects of ethanol and butanol isomers (1-, 2- and t-butanol) on astroglial cell proliferation induced by the strongly mitogenic phorbol ester, 4beta-phorbol-12alpha,13beta-dibutyrate (PDB). 4beta-Phorbol-12alpha,13beta-dibutyrate (PDB) induced a 10-fold increase of [3H] thymidine incorporation in cortical astrocytes prepared from newborn rats (EC50: 70 nM) which was blocked by Ro 31-8220, a cell-permeable protein kinase C (PKC) inhibitor. Ethanol blocked PDB-induced astroglial proliferation in a concentration-dependent manner; significant effects were already seen at 0.1% (v/v). Concomitantly, ethanol caused the formation of phosphatidylethanol (PEth) by phospholipase D (PLD) and reduced PLD-mediated formation of phosphatidic acid (PA). The butanols also inhibited the mitogenic action of phorbol ester; the inhibitory potency of the butanols was 1-butanol > 2-butanol > t-butanol. The same range of potencies was observed for the inhibitory activity of the butanols towards protein kinase C activity measured in vitro. At 0.3% concentration, 1-butanol potently suppressed the PDB-induced formation of phosphatidic acid while 2- and t-butanol were less active. Taken together, our results suggest that ethanol and 1-butanol exert a specific inhibitory effect on PKC-dependent astroglial cell proliferation by synergistically inhibiting PKC activity and the PLD signaling pathway.

  9. MiR-21 inhibits c-Ski signaling to promote the proliferation of rat vascular smooth muscle cells.

    Science.gov (United States)

    Li, Jun; Zhao, Li; He, Xie; Yang, Ting; Yang, Kang

    2014-04-01

    Previously, we reported that the decrease of endogenous c-Ski expression is implicated in the progression of vascular smooth muscle cell (VSMC) proliferation after arterial injury. However, the molecular mechanism of the down-regulation of c-Ski is not clear. In this study, a potential miR-21 recognition element was identified in the 3'-untranslated region (UTR) of rat c-Ski mRNA. A reporter assay revealed that miR-21 could recognize the miR-21 recognition element of c-Ski mRNA. In A10 rat aortic smooth muscle cells, overexpression of miR-21 significantly inhibited the expression of c-Ski protein and promoted cell proliferation, which could be blocked by inhibition of miR-21 or overexpression of c-Ski. Further investigation demonstrated that the effect of miR-21 on VSMC proliferation resulted from negative regulation of c-Ski to suppress p38-p21/p27 signaling, the downstream pathway of c-Ski in VSMCs. These results indicate that c-Ski is a target gene of miR-21. miR-21 specifically binds to the 3'-untranslated region of c-Ski and negatively regulates c-Ski expression to diminish the protective effects of c-Ski and stimulate VSMC proliferation in the progression of arterial injury.

  10. Dexamethasone suppresses DU145 cell proliferation and cell cycle through inhibition of the extracellular signal-regulated kinase 1/2 pathway and cyclin D1 expression

    Institute of Scientific and Technical Information of China (English)

    Qing-Zhen Gao; Jia-Ju Lu; Zi-Dong Liu; Hui Zhang; Shao-Mei Wang; He Xu

    2008-01-01

    Aim: To determine the mechanisms of glucocorticoids in inhibiting advanced prostate cancer growth. Methods: The cell proliferation and cell cycle of prostate cancer DU145 cells following dexamethasone treatment were determined by proliferation assay and fluorescence-activated cell sorter. Western blot analysis was carried out to evaluate the effects of dexamethasone on phosphorylation of extracellular signal-regulated kinase (ERK)1/2 and expression of cyclin D1 in DU145 cells with or without glucocorticoid receptor (GR) antagonist RU486. Reverse transcription- polymerase chain reaction verified the expression of GR mRNA in DU145 cells. Results: Dexamethasone signifi- cantly inhibited DU145 cell proliferation at the G0/G1 phase. Western blot analysis showed a dramatic reduction of ERK1/2 activity and cyclin D1 expression in dexamethasone-treated cells. The decreased phosphorylation of ERK1/2 in dexamethasone-treated cells was attenuated by GR blockade. Additionally, the effects of dexamethasone in inhibiting cyclin D1 expression were altered by GR blockade. Conclusion: Dexamethasone suppresses DU 145 cell prolifera- tion and cell cycle, and the underlying mechanisms are through the inhibition of phosphorylation of ERK1/2 and cyclin D1 expression. The inhibition of ERK1/2 phosphorylation and cyclin D1 expression is attenuated by GR blockade, suggesting that GR regulates ERK1/2 and cyclin D 1 pathways. These observations suggest that dexamethasone has a potential clinical application in prostate cancer therapy. (Asian JAndrol 2008 Jul; 10: 635-641)

  11. Bone morphogenetic protein-9 suppresses growth of myeloma cells by signaling through ALK2 but is inhibited by endoglin

    International Nuclear Information System (INIS)

    Multiple myeloma is a malignancy of plasma cells predominantly located in the bone marrow. A number of bone morphogenetic proteins (BMPs) induce apoptosis in myeloma cells in vitro, and with this study we add BMP-9 to the list. BMP-9 has been found in human serum at concentrations that inhibit cancer cell growth in vitro. We here show that the level of BMP-9 in serum was elevated in myeloma patients (median 176 pg/ml, range 8–809) compared with healthy controls (median 110 pg/ml, range 8–359). BMP-9 was also present in the bone marrow and was able to induce apoptosis in 4 out of 11 primary myeloma cell samples by signaling through ALK2. BMP-9-induced apoptosis in myeloma cells was associated with c-MYC downregulation. The effects of BMP-9 were counteracted by membrane-bound (CD105) or soluble endoglin present in the bone marrow microenvironment, suggesting a mechanism for how myeloma cells can evade the tumor suppressing activity of BMP-9 in multiple myeloma

  12. Butylphthalide Suppresses Neuronal Cells Apoptosis and Inhibits JNK-Caspase3 Signaling Pathway After Brain Ischemia /Reperfusion in Rats.

    Science.gov (United States)

    Wen, Xiang-Ru; Tang, Man; Qi, Da-Shi; Huang, Xiao-Jing; Liu, Hong-Zhi; Zhang, Fang; Wu, Jian; Wang, Yi-Wen; Zhang, Xun-Bao; Guo, Ji-Qiang; Wang, Shu-Ling; Liu, Yong; Wang, Yu-Lan; Song, Yuan-Jian

    2016-10-01

    Although Butylphthalide (BP) has protective effects that reduce ischemia-induced brain damage and neuronal cell death, little is known about the precise mechanisms occurring during cerebral ischemia/reperfusion (I/R). Therefore, the aim of this study was to investigate the neuroprotective mechanisms of BP against ischemic brain injury induced by cerebral I/R through inhibition of the c-Jun N-terminal kinase (JNK)-Caspase3 signaling pathway. BP in distilled non-genetically modified Soybean oil was administered intragastrically three times a day at a dosage of 15 mg/(kg day) beginning at 20 min after I/R in Sprague-Dawley rats. Immunohistochemical staining and Western blotting were performed to examine the expression of related proteins, and TUNEL-staining was used to detect the percentage of neuronal apoptosis in the hippocampal CA1 region. The results showed that BP could significantly protect neurons against cerebral I/R-induced damage. Furthermore, the expression of p-JNK, p-Bcl2, p-c-Jun, FasL, and cleaved-caspase3 was also decreased in the rats treated with BP. In summary, our results imply that BP could remarkably improve the survival of CA1 pyramidal neurons in I/R-induced brain injury and inhibit the JNK-Caspase3 signaling pathway. PMID:27015680

  13. Piperlongumine inhibits gastric cancer cells via suppression of the JAK1,2/STAT3 signaling pathway.

    Science.gov (United States)

    Song, Baoji; Zhan, Hongjie; Bian, Quan; Gu, Junping

    2016-05-01

    Piperlongumine (PL), a major active component of long peppers, has been reported to possess anti‑cancer properties; however, its effect on gastric cancer (GC) has remained to be demonstrated. The present study assessed the effects of PL on the MKN45 and AGS GC cell lines and explored the underlying mechanisms. An MTT assay revealed that PL suppressed the proliferation of GC cells, while flow cytometric analysis showed that PL inhibited cell cycle progression. Furthermore, Transwell assays revealed the inhibitory effects of PL on the invasion and migration of GC cells. In addition, PL reduced the phosphorylation of Janus kinase (JAK)1, JAK2 and signal transducer and activator of transcription (STAT)3 in a concentration‑dependent manner, as indicated by western blot analysis, and decreased the expression of STAT3‑dependent tumor‑associated genes in GC cells, as revealed by PCR analysis. In conclusion, the present study was the first, to the best of our knowledge, to reveal the efficacy of PL against GC. The consumption of long peppers is therefore recommended for the prevention and treatment of GC, and PL may be a promising candidate drug for treating GC. PMID:27053336

  14. MiR-122 directly inhibits human papillomavirus E6 gene and enhances interferon signaling through blocking suppressor of cytokine signaling 1 in SiHa cells.

    Directory of Open Access Journals (Sweden)

    Junming He

    Full Text Available Human Papillomavirus (HPV 16 infection is considered as one of the significant causes of human cervical cancer. The expression of the viral oncogenes like E6 and E7 play an important role in the development of the cancer. MiR-122 has been reported to exhibit a strong relationship with hepatitis viruses and take part in several tumor development, while the effects of miR-122 on HPV infection and the HPV viral oncogenes expression still remain unexplored. In this study, using RNAhybrid software, the potential binding sites between miR-122 and HPV16 E6 and E7 mRNAs were identified. Over and loss of miR-122 function showed that miR-122 could directly bind with HPV16 E6 mRNA and significantly inhibit its expression in SiHa cells, which was further confirmed by constructing the miR-122-E6-mu to eliminate the miR-122 binding effects with E6. The increase of the expression of type I interferon (IFN and its classical effective molecules and the phosphorylation of signal transducers and activators of transcription (STAT1 protein indicated that miR-122 might enhance type I interferon in cervical carcinoma cells, which explained the significant reduction of HPV16 E7 and E6*I mRNA expression. This might be due to the binding between miR-122 and suppressor of cytokine signaling 1 (SOCS1 mRNA, which is the suppressor of interferon signaling pathway. Moreover, it was identified that the miR-122 binding position was nt359-nt375 in SOCS1 mRNA. Taken together, this study indicated that HPV16 could be effectively inhibited by miR-122 through both direct binding with E6 mRNA and promoting SOCS1-dependent IFN signaling pathway. Thus, miR-122 may serve as a new therapeutic option for inhibiting HPV infection.

  15. Concurrent inhibition of kit- and FcepsilonRI-mediated signaling: coordinated suppression of mast cell activation

    DEFF Research Database (Denmark)

    Jensen, Bettina M; Beaven, Michael A; Iwaki, Shoko;

    2008-01-01

    characterized Kit inhibitor imatinib mesylate (imatinib). In contrast to imatinib, however, hypothemycin also effectively inhibited FcepsilonRI-mediated degranulation and cytokine production in addition to the potentiation of these responses via Kit. The effect of hypothemycin on Kit-mediated responses could...

  16. A TLR4/MD2 fusion protein inhibits LPS-induced pro-inflammatory signaling in hepatic stellate cells

    International Nuclear Information System (INIS)

    Activated hepatic stellate cells (HSCs) play a key role in hepatic fibrogenesis. In injured liver they are the main extracellular matrix protein producing cell type and further perpetuate hepatic injury by secretion of pro-inflammatory mediators. Since LPS-mediated signaling through toll-like receptor 4 (TLR4) has been identified as key fibrogenic signal in HSCs we aimed to test TLR4 as potential target of therapy via ligand-binding soluble receptors. Incubation of human HSCs with a fusion protein between the extracellular domain of TLR4 and MD2 which binds LPS inhibited LPS-induced NFκB and JNK activation. TLR4/MD2 abolished LPS-induced secretion of IL-6, IL-8, MCP1, and RANTES in HSCs. In addition, TLR4/MD2 fused to human IgG-Fc neutralized LPS activity. Since TLR4 mutant mice are resistant to liver fibrosis, the TLR4/MD2 soluble receptor might represent a new therapeutic molecule for liver fibrogenesis in vivo

  17. Induction of apoptosis by genipin inhibits cell proliferation in AGS human gastric cancer cells via Egr1/p21 signaling pathway.

    Science.gov (United States)

    Ko, Hyeonseok; Kim, Jee Min; Kim, Sun-Joong; Shim, So Hee; Ha, Chang Hoon; Chang, Hyo Ihl

    2015-10-01

    Natural compounds are becoming important candidates in cancer therapy due to their cytotoxic effects on cancer cells by inducing various types of programmed cell deaths. In this study, we investigated whether genipin induces programmed cell deaths and mediates in Egr1/p21 signaling pathways in gastric cancer cells. Effects of genipin in AGS cancer cell lines were observed via evaluation of cell viability, ROS generation, cell cycle arrest, and protein and RNA levels of p21, Egr1, as well as apoptotic marker genes. The cell viability of AGS cells reduced by genipin treatment via induction of the caspase 3-dependent apoptosis. Cell cycle arrest was observed at the G2/M phase along with induction of p21 and p21-dependent cyclins. As an upstream mediator of p21, the transcription factor early growth response-1 (Egr1) upregulated p21 through nuclear translocation and binding to the p21 promoter site. Silencing Egr1 expression inhibited the expression of p21 and downstream molecules involved in apoptosis. We demonstrated that genipin treatment in AGS human gastric cancer cell line induces apoptosis via p53-independent Egr1/p21 signaling pathway in a dose-dependent manner.

  18. Calcineurin/NFAT signalling inhibits myeloid haematopoiesis.

    Science.gov (United States)

    Fric, Jan; Lim, Clarice X F; Koh, Esther G L; Hofmann, Benjamin; Chen, Jinmiao; Tay, Hock Soon; Mohammad Isa, Siti Aminah Bte; Mortellaro, Alessandra; Ruedl, Christiane; Ricciardi-Castagnoli, Paola

    2012-04-01

    Nuclear factor of activated T cells (NFAT) comprises a family of transcription factors that regulate T cell development, activation and differentiation. NFAT signalling can also mediate granulocyte and dendritic cell (DC) activation, but it is unknown whether NFAT influences their development from progenitors. Here, we report a novel role for calcineurin/NFAT signalling as a negative regulator of myeloid haematopoiesis. Reconstituting lethally irradiated mice with haematopoietic stem cells expressing an NFAT-inhibitory peptide resulted in enhanced development of the myeloid compartment. Culturing bone marrow cells in media supplemented with Flt3-L in the presence of the calcineurin/NFAT inhibitor Cyclosporin A increased numbers of differentiated DC. Global gene expression analysis of untreated DC and NFAT-inhibited DC revealed differential expression of transcripts that regulate cell cycle and apoptosis. In conclusion, these results provide evidence that calcineurin/NFAT signalling negatively regulates myeloid lineage development. The finding that inhibition of NFAT enhances myeloid development provides a novel insight into understanding how the treatment with drugs targeting calcineurin/NFAT signalling influence the homeostasis of the innate immune system.

  19. Ghrelin inhibits the apoptosis of MC3T3-E1 cells through ERK and AKT signaling pathway

    Energy Technology Data Exchange (ETDEWEB)

    Liang, Qiu-Hua; Liu, Yuan; Wu, Shan-Shan; Cui, Rong-Rong; Yuan, Ling-Qing, E-mail: allenylq@hotmail.com; Liao, Er-Yuan, E-mail: eyliao@21cn.com

    2013-11-01

    Ghrelin is a 28-amino-acid peptide that acts as a natural endogenous ligand of the growth hormone secretagogue receptor (GHSR) and strongly stimulates the release of growth hormone from the hypothalamus–pituitary axis. Previous studies have identified the important physiological effects of ghrelin on bone metabolism, such as regulating proliferation and differentiation of osteoblasts, independent of GH/IGF-1 axis. However, research on effects and mechanisms of ghrelin on osteoblast apoptosis is still rare. In this study, we identified expression of GHSR in MC3T3-E1 cells and determined the effects of ghrelin on the apoptosis of osteoblastic MC3T3-E1 cells and the mechanism involved. Our data demonstrated that ghrelin inhibited the apoptosis of osteoblastic MC3T3-E1 cells induced by serum deprivation, as determined by terminal deoxynucleotidyl transferase-mediated deoxyribonucleotide triphosphate nick end-labeling (TUNEL) and ELISA assays. Moreover, ghrelin upregulated Bcl-2 expression and downregulated Bax expression in a dose-dependent manner. Our study also showed decreased activated caspase-3 activity under the treatment of ghrelin. Further study suggested that ghrelin stimulated the phosphorylation of ERK and AKT. Pretreatment of cells with the ERK inhibitor PD98059, PI3K inhibitor LY294002, and GHSR-siRNA blocked the ghrelin-induced activation of ERK and AKT, respectively; however, ghrelin did not stimulate the phosphorylation of p38 or JNK. PD90859, LY294002 and GHSR-siRNA attenuated the anti-apoptosis effect of ghrelin in MC3T3-E1 cells. In conclusion, ghrelin inhibits the apoptosis of osteoblastic MC3T3-E1 cells induced by serum deprivation, which may be mediated by activating the GHSR/ERK and GHSR/PI3K/AKT signaling pathways. - Highlights: • We explored the effects of ghrelin on serum deprivation-induced MC3T3-E1 cells apoptosis. • Both ELISA and TUNEL were used to detect the apoptosis. • The receptor of ghrelin, GHSR, was expressed in MC3T3-E1

  20. Cetuximab insufficiently inhibits glioma cell growth due to persistent EGFR downstream signaling

    DEFF Research Database (Denmark)

    Hasselbalch, Benedikte; Lassen, Ulrik; Poulsen, Hans S;

    2010-01-01

    Overexpression and/or amplification of the epidermal growth factor receptor (EGFR) is present in 35-45% of primary glioblastoma multiforme tumors and has been correlated with a poor prognosis. In this study, we investigated the effect of cetuximab and intracellular signaling pathways downstream o...

  1. 6-Shogaol from dried ginger inhibits growth of prostate cancer cells both in vitro and in vivo through inhibition of STAT3 and NF-κB signaling.

    Science.gov (United States)

    Saha, Achinto; Blando, Jorge; Silver, Eric; Beltran, Linda; Sessler, Jonathan; DiGiovanni, John

    2014-06-01

    Despite much recent progress, prostate cancer continues to represent a major cause of cancer-related mortality and morbidity in men. Prostate cancer is the most common nonskin neoplasm and second leading cause of death in men. 6-Shogaol (6-SHO), a potent bioactive compound in ginger (Zingiber officinale Roscoe), has been shown to possess anti-inflammatory and anticancer activity. In the present study, the effect of 6-SHO on the growth of prostate cancer cells was investigated. 6-SHO effectively reduced survival and induced apoptosis of cultured human (LNCaP, DU145, and PC3) and mouse (HMVP2) prostate cancer cells. Mechanistic studies revealed that 6-SHO reduced constitutive and interleukin (IL)-6-induced STAT3 activation and inhibited both constitutive and TNF-α-induced NF-κB activity in these cells. In addition, 6-SHO decreased the level of several STAT3 and NF-κB-regulated target genes at the protein level, including cyclin D1, survivin, and cMyc and modulated mRNA levels of chemokine, cytokine, cell cycle, and apoptosis regulatory genes (IL-7, CCL5, BAX, BCL2, p21, and p27). 6-SHO was more effective than two other compounds found in ginger, 6-gingerol, and 6-paradol at reducing survival of prostate cancer cells and reducing STAT3 and NF-κB signaling. 6-SHO also showed significant tumor growth inhibitory activity in an allograft model using HMVP2 cells. Overall, the current results suggest that 6-SHO may have potential as a chemopreventive and/or therapeutic agent for prostate cancer and that further study of this compound is warranted. PMID:24691500

  2. Platelet endothelial cell adhesion molecule-1 signaling inhibits the activation of human platelets

    OpenAIRE

    Cicmil, Milenko; Stevens, Jo; Leduc, Mireille; Bon, Cassian; Gibbins, Jonathan M.

    2002-01-01

    Platelet endothelial cell adhesion molecule-1 (PECAM-1/CD31) is a 130-kd transmembrane glycoprotein and a member of the growing family of receptors with immunoreceptor tyrosine-based inhibitory motifs (ITIMs). PECAM-1 is expressed on platelets, certain T cells, monocytes, neutrophils, and vascular endothelial cells and is involved in a range of cellular processes, though the role of PECAM-1 in platelets is unclear. Cross-linking of PECAM-1 results in phosphorylation of the ITIM allowing the r...

  3. Rapamycin reverses NPM-ALK-induced glucocorticoid resistance in lymphoid tumor cells by inhibiting mTOR signaling pathway, enhancing G1 cell cycle arrest and apoptosis.

    Science.gov (United States)

    Gu, L; Gao, J; Li, Q; Zhu, Y P; Jia, C S; Fu, R Y; Chen, Y; Liao, Q K; Ma, Z

    2008-11-01

    The anaplastic lymphoma kinase (ALK) is an oncogene product involved in hematopoietic and non-hematopoietic malignancies. Recent studies have demonstrated that nucleophosmin (NPM)-ALK, originated from the fusion of NPM and ALK genes, causes cell transformation through diverse mechanisms. Here, we show a novel mechanism by which NPM-ALK transforms lymphoid tumor cells to become resistant to glucocorticoid (GC) or dexamethasone (Dex) treatment. Transformed BaF3 cells by NPM-ALK were much more resistant to Dex compared with their parental cells, and concurrently had a constitutive activation of mammalian target of rapamycin (mTOR) signaling, as evidenced by hyperphosphorylation of its downstream effectors, p70 S6 kinase (p70S6K) and eukaryotic initiation factor 4E-binding protein 1 (4E-BP1). The mTOR inhibitor rapamycin suppressed activation of p70S6K in BaF3/NPM-ALK cells and reversed GC resistance by synergistically inhibiting mTOR signaling pathway, enhancing cell cycle arrest at G(1) phase and promoting apoptotic cell death. In conclusion, our data indicate that the ALK fusion kinase, NPM-ALK, induces GC resistance by activating mTOR signaling, and addition of mTOR inhibitors to the chemotherapeutic regimen of ALK+ lymphomas may improve the prognosis.

  4. LKB1/AMPK inhibits TGF-β1 production and the TGF-β signaling pathway in breast cancer cells.

    Science.gov (United States)

    Li, Nian-Shuang; Zou, Jun-Rong; Lin, Hui; Ke, Rong; He, Xiao-Ling; Xiao, Lu; Huang, Deqiang; Luo, Lingyu; Lv, Nonghua; Luo, Zhijun

    2016-06-01

    Adenosine monophosphate-activated protein kinase (AMPK) acts as a fuel gauge that maintains energy homeostasis in both normal and cancerous cells, and has emerged as a tumor suppressor. The present study aims to delineate the functional relationship between AMPK and transforming growth factor beta (TGF-β). Our results showed that expression of liver kinase B1 (LKB1), an upstream kinase of AMPK, impeded TGF-β-induced Smad phosphorylation and their transcriptional activity in breast cancer cells, whereas knockdown of LKB1 or AMPKα1 subunit by short hairpin RNA (shRNA) enhanced the effect of TGF-β. Furthermore, AMPK activation reduced the promoter activity of TGF-β1. In accordance, type 2 diabetic patients taking metformin displayed a trend of reduction of serum TGF-β1, as compared with those without metformin. A significant reduction of serum TGF-β1 was found in mice after treatment with metformin. These results suggest that AMPK inhibits the transcription of TGF-β1, leading to reduction of its concentration in serum. Finally, metformin suppressed epithelial-to-mesenchymal transition of mammary epithelial cells. Taken together, our study demonstrates that AMPK exerts multiple actions on TGF-β signaling and supports that AMPK can serve as a therapeutic drug target for breast cancer. PMID:26718214

  5. AHP6 inhibits cytokinin signaling to regulate the orientation of pericycle cell division during lateral root initiation.

    Directory of Open Access Journals (Sweden)

    Sofia Moreira

    Full Text Available In Arabidopsis thaliana, lateral roots (LRs initiate from anticlinal cell divisions of pericycle founder cells. The formation of LR primordia is regulated antagonistically by the phytohormones cytokinin and auxin. It has previously been shown that cytokinin has an inhibitory effect on the patterning events occurring during LR formation. However, the molecular players involved in cytokinin repression are still unknown. In a similar manner to protoxylem formation in Arabidopsis roots, in which AHP6 (ARABIDOPSIS HISTIDINE PHOSPHOTRANSFER PROTEIN 6 acts as a cytokinin inhibitor, we reveal that AHP6 also functions as a cytokinin repressor during early stages of LR development. We show that AHP6 is expressed at different developmental stages during LR formation and is required for the correct orientation of cell divisions at the onset of LR development. Moreover, we demonstrate that AHP6 influences the localization of the auxin efflux carrier PIN1, which is necessary for patterning the LR primordia. In summary, we show that the inhibition of cytokinin signaling through AHP6 is required to establish the correct pattern during LR initiation.

  6. LKB1/AMPK inhibits TGF-β1 production and the TGF-β signaling pathway in breast cancer cells.

    Science.gov (United States)

    Li, Nian-Shuang; Zou, Jun-Rong; Lin, Hui; Ke, Rong; He, Xiao-Ling; Xiao, Lu; Huang, Deqiang; Luo, Lingyu; Lv, Nonghua; Luo, Zhijun

    2016-06-01

    Adenosine monophosphate-activated protein kinase (AMPK) acts as a fuel gauge that maintains energy homeostasis in both normal and cancerous cells, and has emerged as a tumor suppressor. The present study aims to delineate the functional relationship between AMPK and transforming growth factor beta (TGF-β). Our results showed that expression of liver kinase B1 (LKB1), an upstream kinase of AMPK, impeded TGF-β-induced Smad phosphorylation and their transcriptional activity in breast cancer cells, whereas knockdown of LKB1 or AMPKα1 subunit by short hairpin RNA (shRNA) enhanced the effect of TGF-β. Furthermore, AMPK activation reduced the promoter activity of TGF-β1. In accordance, type 2 diabetic patients taking metformin displayed a trend of reduction of serum TGF-β1, as compared with those without metformin. A significant reduction of serum TGF-β1 was found in mice after treatment with metformin. These results suggest that AMPK inhibits the transcription of TGF-β1, leading to reduction of its concentration in serum. Finally, metformin suppressed epithelial-to-mesenchymal transition of mammary epithelial cells. Taken together, our study demonstrates that AMPK exerts multiple actions on TGF-β signaling and supports that AMPK can serve as a therapeutic drug target for breast cancer.

  7. Nuclear Factor-κB Signaling Pathway Constitutively Activated in Esophageal Squamous Cell Carcinoma Cell Lines and Inhibition of Growth of Cells by Small Interfering RNA

    Institute of Scientific and Technical Information of China (English)

    Fang TIAN; Wei-Dong ZANG; Wei-Hong HOU; Hong-Tao LIU; Le-Xun XUE

    2006-01-01

    Although constitutive nuclear factor (NF)-κB activation has been reported in many human tumors, the role of the NF-κB pathway in esophageal squamous cell carcinoma (ESCC) has not been known.In this study, NF-κB pathway in two ESCC cell lines was investigated using immunocytochemistry, Western blot and reverse transcription-polymerase chain reaction. The activation of NF-κB DNA binding was determined by electrophoretic mobility-shift assay. RNA interference was used to specifically inhibit the expression of p65. Growth of cells was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay.The results showed that p50, p65, Iκ Bα, p-Iκ Bα and Iκ B kinase β were expressed and mainly localized in the cytoplasm. Reverse transcription-polymerase chain reaction results showed the constitutive expressions of p50, p65 and Iκ Bα mRNA in the two ESCC cell lines. Furthermore, the nuclear extracts revealed that p50 and p65 translocated to the nucleus had DNA-binding activity. Finally, small interfering RNA of p65 decreased the expression of p65, and the viability of cells transfected with p65 small interfering RNA was significantly suppressed at the same concentration of 5-fluorouracil (P<0.05) compared to untransfected cells. The results of this study showed that there was the constitutively activated NF-κB signaling pathway in the ESCC cell lines. RNA interference targeting at p65 increased the sensitivity of the ESCC cell lines to 5-fluorouracil,suggesting that NF-κB might be a good target for cancer treatment.

  8. Nobiletin inhibits epithelial-mesenchymal transition of human non-small cell lung cancer cells by antagonizing the TGF-β1/Smad3 signaling pathway.

    Science.gov (United States)

    Da, Chunli; Liu, Yuting; Zhan, Yiyi; Liu, Kai; Wang, Ruozheng

    2016-05-01

    Epithelial-mesenchymal transition (EMT) is a critical cellular process in cancer metastasis, during which epithelial polarized cells become motile mesenchymal cells. Since transforming growth factor-β (TGF-β) is a potent inducer of EMT, blocking of TGF-β/Smad signaling has become a promising cancer therapy. Nobiletin, a polymethoxy flavonoid from Citrus depressa, has been shown to be valuable for cancer treatment, yet the mechanism remains unclear. In the present study, lung adenocarcinoma A549 and H1299 cells were used to evaluate the effect of nobiletin on EMT induced by TGF-β1. Nobiletin successfully inhibited TGF-β1-induced EMT, migration, invasion and adhesion in vitro, accompanied by attenuation of MMP-2, MMP-9, p-Src, p-FAK, p-paxillin, Snail, Slug, Twist and ZEB1 expression. Nobiletin inhibited the transcriptional activity of Smads without changing the phosphorylation status or translocation of Smads induced by TGF-β1. Moreover, Smad3 is requisite in TGF-β1-stimulated EMT. Smad3 overexpression meaningfully impaired the ability of nobiletin to reverse TGF-β1-induced EMT. In vivo, nobiletin prohibited the growth of metastatic nodules in the lungs of nude mice. Moreover, nobiletin inhibited tumor growth and reversed EMT in mice bearing A549-Luc xenografts, as revealed by IVIS imaging and immunohistochemical analysis. Collectively, the data suggest that nobiletin prevents EMT by inactivating TGF-β1/Smad3 signaling. PMID:26986176

  9. Targeting Stem Cell Behavior in Desmoid Tumors (Aggressive Fibromatosis) by Inhibiting Hedgehog Signaling1

    OpenAIRE

    Ghanbari-Azarnier, Ronak; Sato, Shingo; Wei, Qingxia; Al-Jazrawe, Mushriq; Alman, Benjamin A.

    2013-01-01

    Desmoid tumor (also called aggressive fibromatosis) is a lesion of mesenchymal origin that can occur as a sporadic tumor or a manifestation of the preneoplastic syndrome, familial adenomatous polyposis caused by a mutation in adenomatous polyposis coli (APC). This tumor type is characterized by the stabilization of β-catenin and activation of Tcf-mediated transcription. Cell transplantation data suggest that desmoid tumors are derived from mesenchymal progenitor cells (MSCs). As such, modulat...

  10. Cardiotoxin III Inhibits Proliferation and Migration of Oral Cancer Cells through MAPK and MMP Signaling

    Directory of Open Access Journals (Sweden)

    Ching-Yu Yen

    2013-01-01

    Full Text Available Cardiotoxin III (CTXIII, isolated from the snake venom of Formosan cobra Naja naja atra, has previously been found to induce apoptosis in many types of cancer. Early metastasis is typical for the progression of oral cancer. To modulate the cell migration behavior of oral cancer is one of the oral cancer therapies. In this study, the possible modulating effect of CTXIII on oral cancer migration is addressed. In the example of oral squamous carcinoma Ca9-22 cells, the cell viability was decreased by CTXIII treatment in a dose-responsive manner. In wound-healing assay, the cell migration of Ca9-22 cells was attenuated by CTXIII in a dose- and time-responsive manner. After CTXIII treatment, the MMP-2 and MMP-9 protein expressions were downregulated, and the phosphorylation of JNK and p38-MAPK was increased independent of ERK phosphorylation. In conclusion, CTXIII has antiproliferative and -migrating effects on oral cancer cells involving the p38-MAPK and MMP-2/-9 pathways.

  11. FGFR1 signaling stimulates proliferation of human mesenchymal stem cells by inhibiting the cyclin-dependent kinase inhibitors p21(Waf1) and p27(Kip1).

    Science.gov (United States)

    Dombrowski, Christian; Helledie, Torben; Ling, Ling; Grünert, Martin; Canning, Claire A; Jones, C Michael; Hui, James H; Nurcombe, Victor; van Wijnen, Andre J; Cool, Simon M

    2013-12-01

    Signaling through fibroblast growth factor receptor one (FGFR1) is a known inducer of proliferation in both embryonic and human adult mesenchymal stem cells (hMSCs) and positively regulates maintenance of stem cell viability. Leveraging the mitogenic potential of FGF2/FGFR1 signaling in stem cells for therapeutic applications necessitates a mechanistic understanding of how this receptor stimulates cell cycle progression. Using small interfering RNA (siRNA) depletion, antibody-inhibition, and small molecule inhibition, we establish that FGFR1 activity is rate limiting for self-renewal of hMSCs. We show that FGFR1 promotes stem cell proliferation through multiple mechanisms that unite to antagonize cyclin-dependent kinase (CDK) inhibitors. FGFR1 not only stimulates c-Myc to suppress transcription of the CDK inhibitors p21(Waf1) and p27(Kip1), thus promoting cell cycle progression but also increases the activity of protein kinase B (AKT) and the level of S-phase kinase-associated protein 2 (Skp2), resulting in the nuclear exclusion and reduction of p21(Waf1). The in vivo importance of FGFR1 signaling for the control of proliferation in mesenchymal progenitor populations is underscored by defects in ventral mesoderm formation during development upon inhibition of its signaling. Collectively, these studies demonstrate that FGFR1 signaling mediates the continuation of MSC growth and establishes a receptor target for enhancing the expansion of mesenchymal progenitors while maintaining their multilineage potential.

  12. Chloroquine targets pancreatic cancer stem cells via inhibition of CXCR4 and hedgehog signaling

    DEFF Research Database (Denmark)

    Balic, Anamaria; Sørensen, Morten Dræby; Trabulo, Sara Maria;

    2014-01-01

    Pancreatic ductal adenocarcinoma is one of the deadliest carcinomas and is characterized by highly tumorigenic and metastatic cancer stem cells (CSC). CSCs evade available therapies, which preferentially target highly proliferative and more differentiated progenies, leaving behind CSCs...... as a putative source for disease relapse. Thus, to identify potentially more effective treatment regimens, we screened established and new compounds for their ability to eliminate CSCs in primary pancreatic cancer (stem) cells in vitro and corresponding patient-derived pancreatic cancer tissue xenografts...... in vivo. Intriguingly, we found that in vitro treatment with the antimalarial agent chloroquine significantly decreased CSCs, translating into diminished in vivo tumorigenicity and invasiveness in a large panel of pancreatic cancers. In vivo treatment in combination with gemcitabine was capable of more...

  13. Inhibition of STAT3, FAK and Src mediated signaling reduces cancer stem cell load, tumorigenic potential and metastasis in breast cancer

    OpenAIRE

    Thakur, Ravi; Trivedi, Rachana; Rastogi, Namrata; Singh, Manisha; Mishra, Durga Prasad

    2015-01-01

    Cancer stem cells (CSCs) are responsible for aggressive tumor growth, metastasis and therapy resistance. In this study, we evaluated the effects of Shikonin (Shk) on breast cancer and found its anti-CSC potential. Shk treatment decreased the expression of various epithelial to mesenchymal transition (EMT) and CSC associated markers. Kinase profiling array and western blot analysis indicated that Shk inhibits STAT3, FAK and Src activation. Inhibition of these signaling proteins using standard ...

  14. Piperlongumine inhibits atherosclerotic plaque formation and vascular smooth muscle cell proliferation by suppressing PDGF receptor signaling

    OpenAIRE

    Son, Dong Ju; Kim, Soo Yeon; Han, Seong Su; Kim, Chan Woo; Kumar, Sandeep; Park, Byeoung Soo; Lee, Sung Eun; Yun, Yeo Pyo; Jo, Hanjoong; Park, Young Hyun

    2012-01-01

    Piperlongumine (piplartine, PL) is an alkaloid found in the long pepper (Piper longum L.) and has well-documented anti-platelet aggregation, anti-inflammatory, and anti-cancer properties; however, the role of PL in prevention of atherosclerosis is unknown. We evaluated the anti-atherosclerotic potential of PL in an in vivo murine model of accelerated atherosclerosis and defined its mechanism of action in aortic vascular smooth muscle cells (VSMCs) in vitro. Local treatment with PL significant...

  15. Picropodophyllin inhibits the growth of Ewing's sarcoma cells through the insulin‑like growth factor‑1 receptor/Akt signaling pathway.

    Science.gov (United States)

    Wu, Yong-Tao; Wang, Bao-Jun; Miao, Sheng-Wu; Gao, Jian-Jun

    2015-11-01

    Ewing's sarcoma (ES) is the second most common type of pediatric bone tumor, and is associated with a poor prognosis. Picropodophyllin (PPP), a novel selective inhibitor of insulin‑like growth factor‑1 receptor (IGF‑1R), is able to strongly inhibit various types of cancers. However, the effect of IGF‑1R on ES remains unclear. Following treatment with various concentrations of PPP for various times, cell viability was determined using an MTT assay. In addition, cell proliferation and apoptosis was investigated separately by bromodeoxyuridine staining and flow cytometry, respectively. The PPP‑associated signaling pathway was also investigated. The results of the present study suggested that PPP inhibited cell proliferation and viability of A673 and SK‑ES‑1 human Ewing's sarcoma cells in a dose- and time‑dependent manner. In addition, cell apoptosis rates were increased following treatment with PPP. Further investigation of the underlying mechanism revealed that PPP inhibited Akt phosphorylation. Fumonisin B1, an Akt‑specific activator, reversed the inhibitory effects of PPP on cell growth. Furthermore, the results suggested that PPP decreased the expression levels of IGF‑1R, a common activator of Akt signaling. PPP inhibited the growth of human Ewing's sarcoma cells by targeting the IGF‑1R/Akt signaling pathway. Therefore, PPP may prove useful in the development of an effective strategy for the treatment of Ewing's sarcoma.

  16. Atoh7 promotes the differentiation of retinal stem cells derived from Müller cells into retinal ganglion cells by inhibiting Notch signaling

    OpenAIRE

    Song, Wei-tao; Zhang, Xue-yong; Xia, Xiao-Bo

    2013-01-01

    Introduction Retinal Müller cells exhibit the characteristics of retinal progenitor cells, and differentiate into ganglion cells under certain conditions. However, the number of ganglion cells differentiated from retinal Müller cells falls far short of therapeutic needs. This study aimed to develop a novel protocol to promote the differentiation of retinal Müller cells into ganglion cells and explore the underlying signaling mechanisms. Methods Müller cells were isolated and purified from rat...

  17. Mesenchymal stem cells attenuate inflammatory processes in the heart and lung via inhibition of TNF signaling.

    Science.gov (United States)

    Martire, Alessandra; Bedada, Fikru B; Uchida, Shizuka; Pöling, Jochen; Krüger, Marcus; Warnecke, Henning; Richter, Manfred; Kubin, Thomas; Herold, Susanne; Braun, Thomas

    2016-09-01

    Mesenchymal stem cells (MSC) have been used to treat different clinical conditions although the mechanisms by which pathogenetic processes are affected are still poorly understood. We have previously analyzed the homing of bone marrow-derived MSC to diseased tissues characterized by a high degree of mononuclear cell infiltration and postulated that MSC might modulate inflammatory responses. Here, we demonstrate that MSC mitigate adverse tissue remodeling, improve organ function, and extend lifespan in a mouse model of inflammatory dilative cardiomyopathy (DCM). Furthermore, MSC attenuate Lipopolysaccharide-induced acute lung injury indicating a general role in the suppression of inflammatory processes. We found that MSC released sTNF-RI, which suppressed activation of the NFκBp65 pathway in cardiomyocytes during DCM in vivo. Substitution of MSC by recombinant soluble TNF-R partially recapitulated the beneficial effects of MSC while knockdown of TNF-R prevented MSC-mediated suppression of the NFκBp65 pathway and improvement of tissue pathology. We conclude that sTNF-RI is a major part of the paracrine machinery by which MSC effect local inflammatory reactions. PMID:27435289

  18. Suppressor of cytokine signalling (SOCS)-3 protects beta cells against IL-1beta-mediated toxicity through inhibition of multiple nuclear factor-kappaB-regulated proapoptotic pathways

    DEFF Research Database (Denmark)

    Karlsen, Allan Ertman; Heding, P E; Frobøse, H;

    2004-01-01

    The proinflammatory cytokine IL-1beta induces apoptosis in pancreatic beta cells via pathways dependent on nuclear factor-kappaB (NF-kappaB), mitogen-activated protein kinase, and protein kinase C. We recently showed suppressor of cytokine signalling (SOCS)-3 to be a natural negative feedback...... regulator of IL-1beta- and IFN-gamma-mediated signalling in rat islets and beta cell lines, preventing their deleterious effects. However, the mechanisms underlying SOCS-3 inhibition of IL-1beta signalling and prevention against apoptosis remain unknown....

  19. 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

  20. The inhibition of cell proliferation and induction of apoptosis in pancreatic ductal adenocarcinoma cells by verrucarin A, a macrocyclic trichothecene, is associated with the inhibition of Akt/NF-кB/mTOR prosurvival signaling.

    Science.gov (United States)

    Deeb, Dorrah; Gao, Xiaohua; Liu, Yongbo; Zhang, Yiguan; Shaw, Jiajiu; Valeriote, Frederick A; Gautam, Subhash C

    2016-09-01

    Pancreatic ductal adenocarcinoma (PDA) remains one of the most difficult to treat of all malignancies. Multimodality regimens provide only short-term symptomatic improvement with minor impact on survival, underscoring the urgent need for novel therapeutics and treatment strategies for PDA. Trichothecenes are powerful mycotoxins that inhibit protein synthesis and induce ribotoxic stress response in mammalian cells. Verrucarin A (VC-A) is a Type D macrocyclic mycotoxin which inhibited cell proliferation and induced apoptosis in breast cancer cells. However, the antitumor activity of VC-A for PDA cells has not been investigated. Here we show potent antitumor activity and the mechanism of action of VC-A in PDA cell lines. VC-A strongly inhibited the proliferation and arrested cells in the S phase of the cell cycle. The blocking of cell cycle progression by VC-A was associated with the inhibition of cell cycle regulatory proteins cyclin D1, cyclin E, cyclin-dependent kinases (cdks) cdk2, cdk4 and cdk inhibitor WAF1/21. VC-A induced apoptosis in PDA cells as indicated by the increased Annexin V FITC-binding, cleavage of poly(ADP-ribose) polymerase‑1 (PARP-1) and procaspases-3, -8 and -9. VC-A also induced mitochondrial depolarization and release of cytochrome c and it inhibited Bcl-2 family proteins that regulate apoptosis (Bcl-2, Bcl-xL, Bax and Bad). In addition, VC-A reduced the levels of inhibitors of apoptosis survivin and c-IAP-2. Finally, VC-A downregulated the expression of prosurvival phospho-Akt (p-Akt), nuclear factor κB (NF-κB) (p65) and mammalian target of rapamycin (p-mTOR) signaling proteins and their downstream mediators. Together, these results demonstrated strong antiproliferative and apoptosis-inducing activity of verrucarin A for PDA cells through cell cycle arrest and inhibition of the prosurvival (antiapoptotic) AKT/NF-κB/mTOR signaling. PMID:27573873

  1. Gallic acid inhibits gastric cancer cells metastasis and invasive growth via increased expression of RhoB, downregulation of AKT/small GTPase signals and inhibition of NF-κB activity

    International Nuclear Information System (INIS)

    Our previous study demonstrated the therapeutic potential of gallic acid (GA) for controlling tumor metastasis through its inhibitory effect on the motility of AGS cells. A noteworthy finding in our previous experiment was increased RhoB expression in GA-treated cells. The aim of this study was to evaluate the role of RhoB expression on the inhibitory effects of GA on AGS cells. By applying the transfection of RhoB siRNA into AGS cells and an animal model, we tested the effect of GA on inhibition of tumor growth and RhoB expression. The results confirmed that RhoB-siRNA transfection induced GA to inhibit AGS cells’ invasive growth involving blocking the AKT/small GTPase signals pathway and inhibition of NF-κB activity. Finally, we evaluated the effect of GA on AGS cell metastasis by colonization of tumor cells in nude mice. It showed GA inhibited tumor cells growth via the expression of RhoB. These data support the inhibitory effect of GA which was shown to inhibit gastric cancer cell metastasis and invasive growth via increased expression of RhoB, downregulation of AKT/small GTPase signals and inhibition of NF-κB activity. Thus, GA might be a potential agent in treating gastric cancer. Highlights: ► GA could downregulate AKT signal via increased expression of RhoB. ► GA inhibits metastasis in vitro in gastric carcinoma. ► GA inhibits tumor growth in nude mice model.

  2. The Role of Matrine and Mitogen-Ativated Protein Kinase/Extracellular Signal-Regulated Kinase Signal Transduction in the Inhibition of the Proliferation and Migration of Human Umbilical Veins Endothelial Cells Induced by Lung Cancer cells

    Directory of Open Access Journals (Sweden)

    Ming BAI

    2009-07-01

    Full Text Available Background and objective Matrine, one of the major alkaloid components of the traditional Chinese medicine Sophora roots, has a wide range of pharmacological effects including anti-inflammatory activities, growth inhibition and induction of cell differentiation and apoptosis. Motigen-activated protein kinase (MAPK/extracellular signal-regulated kinase (ERK has found to be a crucial signaling pathway in endothelial cells. The aim of this study is to investigate the role of Matrine and MAPK/ERK signal transduction in the inhibition of the proliferation and migration of human umbilical veins endothelial cells (HUVECs induced by lung cancer cells. Methods HUVECs were cultured with A549CM. Mat or PD98059 (i.e PD, specific inhibitor of MAPK/ERK, was added into the A549CM. The proliferation of the HUVECs was measured by cell counting. The migration of the HUVECs was observed by wound healing assay. The expression levels of ERK and p-ERK protein were detected by Western Blot analysis. Results On 24 hours after intervention, the A549CM significantly stimulated the proliferation, migration and expression of p-ERK of HUVECs. Compared with the A549CM group, Mat significantly inhibited the proliferation, migration and p-ERK expression of HUVECs induced by A549CM. While PD only decreased the proliferation and p-ERK expression of HUVECs induced by A549CM. PD had no effect in the migration of HUVECs. Conclusion The results demonstrated that Mat and PD98059 can effectively decrease proliferation and expression of p-ERK of HUVECs induced by A549CM. Furthermore Mat can also inhibit migration of HUVECs induced by A549CM that did not changed by PD98059. These data implied that suppressing MAPK/ERK signal transduction may play the crucial role in resisting lung cacinoma angiogenesis with Mat.

  3. The ETS domain transcriptional repressor Anterior open inhibits MAP kinase and Wingless signaling to couple tracheal cell fate with branch identity.

    Science.gov (United States)

    Caviglia, Sara; Luschnig, Stefan

    2013-03-01

    Cells at the tips of budding branches in the Drosophila tracheal system generate two morphologically different types of seamless tubes. Terminal cells (TCs) form branched lumenized extensions that mediate gas exchange at target tissues, whereas fusion cells (FCs) form ring-like connections between adjacent tracheal metameres. Each tracheal branch contains a specific set of TCs, FCs, or both, but the mechanisms that select between the two tip cell types in a branch-specific fashion are not clear. Here, we show that the ETS domain transcriptional repressor anterior open (aop) is dispensable for directed tracheal cell migration, but plays a key role in tracheal tip cell fate specification. Whereas aop globally inhibits TC and FC specification, MAPK signaling overcomes this inhibition by triggering degradation of Aop in tip cells. Loss of aop function causes excessive FC and TC specification, indicating that without Aop-mediated inhibition, all tracheal cells are competent to adopt a specialized fate. We demonstrate that Aop plays a dual role by inhibiting both MAPK and Wingless signaling, which induce TC and FC fate, respectively. In addition, the branch-specific choice between the two seamless tube types depends on the tracheal branch identity gene spalt major, which is sufficient to inhibit TC specification. Thus, a single repressor, Aop, integrates two different signals to couple tip cell fate selection with branch identity. The switch from a branching towards an anastomosing tip cell type may have evolved with the acquisition of a main tube that connects separate tracheal primordia to generate a tubular network. PMID:23444354

  4. 1α,25-dihydroxyvitamin D3 inhibits cell growth and NFκB signaling in tamoxifen-resistant breast cancer cells.

    Science.gov (United States)

    Lundqvist, Johan; Yde, Christina W; Lykkesfeldt, Anne E

    2014-07-01

    Resistance to antiestrogens is a major clinical problem in current breast cancer treatment and development of new treatment strategies for these tumors is highly prioritized. In this study, we have investigated the effects of 1α,25-dihydroxyvitamin D3 on the proliferation of tamoxifen-resistant cells. Further, we have investigated on a molecular level the effects of vitamin D on NFkB signaling in tamoxifen-resistant breast cancer cells. Parental human breast cancer MCF-7 cells and four tamoxifen-resistant sublines have been used to investigate the effects of 1α,25-dihydroxyvitamin D3 on cell proliferation using a colorimetric method, gene expression using quantitative PCR, protein phosphorylation using Western blot analysis and cellular localization of proteins using immunofluorescence microscopy. We found that 1α,25-dihydroxyvitamin D3 is able to strongly decrease the growth of both tamoxifen-sensitive and -resistant breast cancer cells and that this antiproliferative effect of 1α,25-dihydroxyvitamin D3 might be mediated via inhibition of the NFκB pathway. We found that 1α,25-dihydroxyvitamin D3 stimulates the gene expression of IkB, an NFκB-inhibiting protein, and that cells pretreated with 1α,25-dihydroxyvitamin D3 have a decreased sensitivity to TNFα stimulation. Further, we show that 1α,25-dihydroxyvitamin D3 treatment strongly decreases the TNFα-induced translocation of p65 into the nucleus. This manuscript reports novel findings regarding the effects of 1α,25-dihydroxyvitamin D3 on NFκB signaling in tamoxifen-resistant breast cancer cells and suggests that vitamin D might be interesting for further evaluation as a new strategy to treat antiestrogen-resistant breast cancers.

  5. Parathyroid hormone inhibits TGF-β/Smad signaling and extracellular matrix proteins upregulation in rat mesangial cells.

    Science.gov (United States)

    Peng, Fang-Fang; Xiao, Ze-Ling; Chen, Hong-Min; Chen, Yan; Zhou, Jian; Yu, Hong; Zhang, Bai-Fang

    2016-09-23

    Accumulation of glomerular matrix is a hallmark of diabetic nephropathy. TGF-β1 is a major cytokine mediating the production of various extracellular matrix (ECM) proteins. The aim of this study is to elucidate the effect of parathyroid hormone (PTH) on TGF-β1 and high glucose-induced upregulation of ECM proteins in primary mesangial cells from Sprague-Dawley rat. The results showed that PTH pretreatment prevented TGF-β1 and high glucose-induced Smad2/3 phosphorylation and consequent upregulation of fibronectin and type IV collagen within 4 h. The inhibitory effect of PTH is due to PTH1R activation, because knocking down PTH 1 receptor (PTH1R) by RNA interference reversed the inhibitory effect of PTH on TGF-β1 and high glucose-induced Smad2/3 phosphorylation and ECM upregulation. Furthermore, it is found that PTH1R associated with TGF-β type II receptor (TβR II) and both receptors internalized into the cytoplasm when mesangial cells were stimulated with PTH alone. The internalization of TβR II might reduce the amount of membrane TβR II, attenuate the sensitivity of mesangial cells to TGF-β1, and therefore inhibit Smad activation and ECM upregulation induced by TGF-β1 and high glucose. Further studies are needed to know whether the endocytic receptors are to be degraded or recycled, and evaluate the role of PTH in TGF-β1 signaling more comprehensively.

  6. Morin ameliorates chemically induced liver fibrosis in vivo and inhibits stellate cell proliferation in vitro by suppressing Wnt/β-catenin signaling

    Energy Technology Data Exchange (ETDEWEB)

    MadanKumar, Perumal; NaveenKumar, Perumal; Manikandan, Samidurai [Department of Biochemistry, University of Madras, Guindy Campus, Chennai 600 025, Tamil Nadu (India); Devaraj, Halagowder [Department of Zoology, University of Madras, Guindy Campus, Chennai 600 025, Tamil Nadu (India); NiranjaliDevaraj, Sivasithamparam, E-mail: niranjali@yahoo.com [Department of Biochemistry, University of Madras, Guindy Campus, Chennai 600 025, Tamil Nadu (India)

    2014-06-01

    The anti-fibrotic effect of morin was examined in LX-2 cells (culture-activated human hepatic stellate cells) and in diethylnitrosamine induced rat model of liver fibrosis. The in vitro study was designed to determine whether morin affects the survival of cultured LX-2 cells, while the in vivo study was designed to evaluate the antioxidant and anti-fibrotic efficacy of morin on diethylnitrosamine induced liver fibrosis in male albino Wistar rat. The activities of liver function enzymes in serum, liver lipid peroxide levels, activities of serum antioxidant enzymes and liver architecture were monitored to cast light on the antioxidant and hepatoprotective nature of morin. To establish the anti-fibrotic effects of morin, the levels of key Wnt signaling molecules which are strongly associated with the signal transduction pathway of HSC activation were measured. Overall, from the in vitro results, it was observed that morin at 50 μM concentration inhibited the proliferation of cultured LX-2 cells, inhibited Wnt signaling and induced G1 cell cycle arrest. The in vivo results further confirmed that morin by downregulating the expressions of GSK-3β, β-catenin and cyclin D1 ameliorated DEN-induced liver fibrosis. Hence morin could be employed as a promising chemopreventive natural supplement for liver fibrosis. - Highlights: • In vivo and in vitro results revealed the active participation of Wnt signaling. • Morin at 50 μM inhibited LX-2 cell proliferation by suppressing Wnt signaling. • Morin exhibited hepatoprotective effects against DEN induced liver fibrosis. • Morin inhibited HSC activation in vivo by downregulating Wnt/β-catenin signaling.

  7. Effusanin E suppresses nasopharyngeal carcinoma cell growth by inhibiting NF-κB and COX-2 signaling.

    Directory of Open Access Journals (Sweden)

    Mingzhu Zhuang

    Full Text Available Rabdosia serra is well known for its antibacterial, anti-inflammatory and antitumor activities, but no information has been available for the active compounds derived from this plant in inhibiting human nasopharyngeal carcinoma (NPC cell growth. In this study, we isolated and purified a natural diterpenoid from Rabdosia serra and identified its chemical structure as effusanin E and elucidated its underlying mechanism of action in inhibiting NPC cell growth. Effusanin E significantly inhibited cell proliferation and induced apoptosis in NPC cells. Effusanin E also induced the cleavage of PARP, caspase-3 and -9 proteins and inhibited the nuclear translocation of p65 NF-κB proteins. Moreover, effusanin E abrogated the binding of NF-κB to the COX-2 promoter, thereby inhibiting the expression and promoter activity of COX-2. Pretreatment with a COX-2 or NF-κB-selective inhibitor (celecoxib or ammonium pyrrolidinedithiocarbamate had an additive effect on the effusanin E-mediated inhibition of proliferation, while pretreatment with an activator of NF-κB/COX-2 (lipopolysaccharides abrogated the effusanin E-mediated inhibition of proliferation. Effusanin E also significantly suppressed tumor growth in a xenograft mouse model without obvious toxicity, furthermore, the expression of p50 NF-κB and COX-2 were down-regulated in the tumors of nude mice. These data suggest that effusanin E suppresses p50/p65 proteins to down-regulate COX-2 expression, thereby inhibiting NPC cell growth. Our findings provide new insights into exploring effusanin E as a potential therapeutic compound for the treatment of human nasopharyngeal carcinoma.

  8. Chidamide, a novel histone deacetylase inhibitor, inhibits the viability of MDS and AML cells by suppressing JAK2/STAT3 signaling

    Science.gov (United States)

    Zhao, Sida; Guo, Juan; Zhao, Youshan; Fei, Chengming; Zheng, Qingqing; Li, Xiao; Chang, Chunkang

    2016-01-01

    Many studies have indicated that histone deacetylase (HDAC) activity is always increased in a lot of human tumors, and inhibition of HDAC activity is a promising new strategy in the treatment of cancers. Chidamide, a novel HDAC inhibitor of the benzamide class, is currently under clinical trials. In this study, we aimed to investigate the antitumor activity of Chidamide on myelodysplastic syndromes (MDS) and acute myeloid leukemia (AML) cell lines and explore the possible mechanism. Chidamide exhibited efficient anti-proliferative activity on MDS and AML cells in a time- and dose-dependent manner, accompanied by cell cycle arrest at G0/G1 phase and cell apoptosis. Importantly, Chidamide possessed potent HDAC inhibition property, as evaluated by HDAC activity analysis and acetylation of histone H3 and H4. Moreover, Chidamide significantly increased the expression of Suppressors of cytokine signaling 3 (SOCS3), reduced the expression of Janus activated kinases 2 (JAK2) and Signal transducer and activator of transcription 3 (STAT3), and inhibited STAT3 downstream genes, including c-Myc, Bcl-xL, and Mcl-1, which are involved in cell cycle progression and anti-apoptosis. Therefore, we demonstrate that Chidamide exhibits potent inhibitory effect on cell viability of MDS and AML cells, and the possible mechanism may lie in the downregulation of JAK2/STAT3 signaling through SOCS3 upregulation. Our data provide rationale for clinical investigations of Chidamide in MDS and AML. PMID:27508038

  9. The clerodane diterpene casearin J induces apoptosis of T-ALL cells through SERCA inhibition, oxidative stress, and interference with Notch1 signaling.

    Science.gov (United States)

    De Ford, C; Heidersdorf, B; Haun, F; Murillo, R; Friedrich, T; Borner, C; Merfort, I

    2016-01-28

    T-cell acute lymphoblastic leukemia (T-ALL) is an aggressive hematologic malignancy that preferentially affects children and adolescents. Over 50% of human T-ALLs possess activating mutations of Notch1. The clerodane diterpene casearin J (CJ) is a natural product that inhibits the sarcoendoplasmatic reticulum calcium ATPase (SERCA) pump and induces cell death in leukemia cells, but the molecular mechanism of cytotoxicity remains poorly understood. Here we show that owing to SERCA pump inhibition, CJ induces depletion of the endoplasmic reticulum calcium pools, oxidative stress, and apoptosis via the intrinsic signaling pathway. Moreover, Notch1 signaling is reduced in T-ALL cells with auto-activating mutations in the HD-domain of Notch1, but not in cells that do not depend on Notch1 signaling. CJ also provoked a slight activation of NF-κB, and consistent with this notion a combined treatment of CJ and the NF-κB inhibitor parthenolide (Pt) led to a remarkable synergistic cell death in T-ALL cells. Altogether, our data support the concept that inhibition of the SERCA pump may be a novel strategy for the treatment of T-ALL with HD-domain-mutant Notch1 receptors and that additional treatment with the NF-κB inhibitor parthenolide may have further therapeutic benefits.

  10. Inhibition of CK2α down-regulates Hedgehog/Gli signaling leading to a reduction of a stem-like side population in human lung cancer cells.

    Directory of Open Access Journals (Sweden)

    Shulin Zhang

    Full Text Available Protein kinase CK2 is frequently elevated in a variety of human cancers. The Hedgehog (Hh signaling pathway has been implicated in stem cell maintenance, and its aberrant activation has been indicated in several types of cancer, including lung cancer. In this study, we show that CK2 is positively involved in Hh/Gli signaling in lung cancer cell lines A549 and H1299. First, we found a correlation between CK2α and Gli1 mRNA levels in 100 primary lung cancer tissues. Down-regulation of Gli1 expression and transcriptional activity were demonstrated after the silencing of CK2α in lung cancer cells. In addition, CK2α siRNA down-regulated the expression of Hh target genes. Furthermore, two small-molecule CK2α inhibitors led to a dose-dependent inhibition of Gli1 expression and transcriptional activity in lung cancer cells. Reversely, forced over-expression of CK2α resulted in an increase both in Gli1 expression and transcriptional activity in A549 cells. Finally, the inhibition of Hh/Gli by CK2α siRNA led to a reduction of a cancer stem cell-like side population that shows higher ABCG2 expression level. Thus, we report that the inhibition of CK2α down-regulates Hh/Gli signaling and subsequently reduces stem-like side population in human lung cancer cells.

  11. Radiosensitization of Non-Small Cell Lung Cancer Cells by Inhibition of TGF-β1 Signaling With SB431542 Is Dependent on p53 Status.

    Science.gov (United States)

    Zhao, Yifan; Wang, Longxiao; Huang, Qianyi; Jiang, Youqin; Wang, Jingdong; Zhang, Liyuan; Tian, Ye; Yang, Hongying

    2016-01-01

    Although medically inoperable patients with stage I non-small cell lung cancer cells (NSCLC) are often treated with stereotactic body radiation therapy, its efficacy can be compromised due to poor radiosensitivity of cancer cells. Inhibition of transforming growth factor-β1 (TGF-β1) using LY364947 and LY2109761 has been demonstrated to radiosensitize cancer cells such as breast cancer, glioblastoma, and lung cancer. Our previous results have demonstrated that another potent and selective inhibitor of TGF-β1 receptor kinases, SB431542, could radiosensitize H460 cells both in vitro and in vivo. In the present study, we investigated whether SB431542 could radiosensitize other NSCLC cell lines, trying to explore the potential implication of this TGF-β1 inhibitor in radiotherapy for NSCLC patients. The results showed that A549 cells were significantly radiosensitized by SB431542, whereas no radiosensitizing effect was observed in H1299 cells. Interestingly, both H460 and A549 cells have wild-type p53, while H1299 cells have deficient p53. To study whether the radiosensitizing effect of SB431542 was associated with p53 status of cancer cells, the p53 of H460 cells was silenced using shRNA transfection. Then it was found that the radiosensitizing effect of SB431542 on H460 cells was not observed in H460 cells with silenced p53. Moreover, X-irradiation caused rapid Smad2 activation in H460 and A549 cells but not in H1299 and H460 cells with silenced p53. The Smad2 activation postirradiation could be abolished by SB431542. This may explain the lack of radiosensitizing effect of SB431542 in H1299 and H460 cells with silenced p53. Thus, we concluded that the radiosensitizing effect of inhibition of TGF-β1 signaling in NSCLC cells by SB431542 was p53 dependent, suggesting that using TGF-β1 inhibitor in radiotherapy may be more complicated than previously thought and may need further investigation. PMID:27178816

  12. Herbal Extract SH003 Suppresses Tumor Growth and Metastasis of MDA-MB-231 Breast Cancer Cells by Inhibiting STAT3-IL-6 Signaling

    Directory of Open Access Journals (Sweden)

    Youn Kyung Choi

    2014-01-01

    Full Text Available Cancer inflammation promotes cancer progression, resulting in a high risk of cancer. Here, we demonstrate that our new herbal extract, SH003, suppresses both tumor growth and metastasis of MDA-MB-231 breast cancer cells via inhibiting STAT3-IL-6 signaling path. Our new herbal formula, SH003, mixed extract from Astragalus membranaceus, Angelica gigas, and Trichosanthes kirilowii Maximowicz, suppressed MDA-MB-231 tumor growth and lung metastasis in vivo and reduced the viability and metastatic abilities of MDA-MB-231 cells in vitro. Furthermore, SH003 inhibited STAT3 activation, which resulted in a reduction of IL-6 production. Therefore, we conclude that SH003 suppresses highly metastatic breast cancer growth and metastasis by inhibiting STAT3-IL-6 signaling path.

  13. Piperlongumine Inhibits Migration of Glioblastoma Cells via Activation of ROS-Dependent p38 and JNK Signaling Pathways

    OpenAIRE

    Qian Rong Liu; Ju Mei Liu; Yong Chen; Xiao Qiang Xie; Xin Xin Xiong; Xin Yao Qiu; Feng Pan; Di Liu; Shang Bin Yu; Xiao Qian Chen

    2014-01-01

    Piperlongumine (PL) is recently found to kill cancer cells selectively and effectively via targeting reactive oxygen species (ROS) responses. To further explore the therapeutic effects of PL in cancers, we investigated the role and mechanisms of PL in cancer cell migration. PL effectively inhibited the migration of human glioma (LN229 or U87 MG) cells but not normal astrocytes in the scratch-wound culture model. PL did ...

  14. Decreased Autocrine EGFR Signaling in Metastatic Breast Cancer Cells Inhibits Tumor Growth in Bone and Mammary Fat Pad

    OpenAIRE

    Nickerson, Nicole K.; Mohammad, Khalid S.; Gilmore, Jennifer L.; Crismore, Erin; Bruzzaniti, Angela; Guise, Theresa A.; Foley, John

    2012-01-01

    Breast cancer metastasis to bone triggers a vicious cycle of tumor growth linked to osteolysis. Breast cancer cells and osteoblasts express the epidermal growth factor receptor (EGFR) and produce ErbB family ligands, suggesting participation of these growth factors in autocrine and paracrine signaling within the bone microenvironment. EGFR ligand expression was profiled in the bone metastatic MDA-MB-231 cells (MDA-231), and agonist-induced signaling was examined in both breast cancer and oste...

  15. Targeting Transforming Growth Factor-Beta1 (TGF-β1) Inhibits Tumorigenesis of Anaplastic Thyroid Carcinoma Cells Through ERK1/2-NFκkB-PUMA Signaling.

    Science.gov (United States)

    Yin, Qiang; Liu, Shan; Dong, Anbing; Mi, Xiufang; Hao, Fengyun; Zhang, Kejun

    2016-01-01

    BACKGROUND The transforming growth factor-beta (TGF-β) signaling pathway plays a critical role in promoting tumor growth. TGF-β1was found to be overexpressed in anaplastic thyroid cancer (ATC). We therefore tested our hypothesis that targeting TGF-β1 inhibits tumorigenesis of ATC cells. MATERIAL AND METHODS Effects of TGF-β1 stimulation or TGF-β1 inhibition by small interfering RNA (TGF-β1siRNA) on proliferation, colony formation, and apoptosis in 8505C cells in vitro was detected using siRNAs and inhibitors to examine the TGF-β1 signaling pathway. A subcutaneously implanted tumor model of 8505C cells in nude mice was used to assess the effects of TGF-β1 inhibition on tumorigenesis development. RESULTS TGF-β1siRNAs decreased proliferation and colony formation, and increased apoptosis in 8505C cells in vitro and inhibited tumor growth in vivo. TGF-β1siRNA inhibited phosphorylation ERK1/2 (pERK1/2) and increased p65-dependant PUMA mRNA and protein expression. Knockdown of p65 or PUMA by siRNA reduced TGF-β1siRNA-induced apoptosis, as well as caspase-3 and PARP activation. Upregulation of p65 or PUMA expression by TGF-β1siRNA requires pERK1/2 inhibition. TGF-β1 shRNA inhibited tumor growth in vivo. CONCLUSIONS Therapies targeting the TGF-β1 pathway may be more effective to prevent primary tumor formation. The ability of this therapy to decrease tumorigenesis may be related to ERK1/2/NF-κB/PUMA signaling. PMID:27356491

  16. Lasiodin inhibits proliferation of human nasopharyngeal carcinoma cells by simultaneous modulation of the Apaf-1/caspase, AKT/MAPK and COX-2/NF-κB signaling pathways.

    Directory of Open Access Journals (Sweden)

    Lianzhu Lin

    Full Text Available Rabdosia serra has been widely used for the treatment of the various human diseases. However, the antiproliferative effects and underlying mechanisms of the compounds in this herb remain largely unknown. In this study, an antiproliferative compound against human nasopharyngeal carcinoma (NPC cells from Rabdosia serra was purified and identified as lasiodin (a diterpenoid. The treatment with lasiodin inhibited cell viability and migration. Lasiodin also mediated the cell morphology change and induced apoptosis in NPC cells. The treatment with lasiodin induced the Apaf-1 expression, triggered the cytochrome-C release, and stimulated the PARP, caspase-3 and caspase-9 cleavages, thereby activating the apoptotic pathways. The treatment with lasiodin also significantly inhibited the phosphorylations of the AKT, ERK1/2, p38 and JNK proteins. The pretreatment with the AKT or MAPK-selective inhibitors considerably blocked the lasiodin-mediated inhibition of cell proliferation. Moreover, the treatment with lasiodin inhibited the COX-2 expression, abrogated NF-κB binding to the COX-2 promoter, and promoted the NF-κB translocation from cell nuclei to cytosol. The pretreatment with a COX-2-selective inhibitor abrogated the lasiodin-induced inhibition of cell proliferation. These results indicated that lasiodin simultaneously activated the Apaf-1/caspase-dependent apoptotic pathways and suppressed the AKT/MAPK and COX-2/NF-κB signaling pathways. This study also suggested that lasiodin could be a promising natural compound for the prevention and treatment of NPC.

  17. Inhibition of BRD4 attenuates tumor cell self-renewal and suppresses stem cell signaling in MYC driven medulloblastoma

    OpenAIRE

    Venkataraman, Sujatha; Alimova, Irina; Balakrishnan, Ilango; Harris, Peter; Birks, Diane K; Griesinger, Andrea; Amani, Vladimir; Cristiano, Brian; Remke, Marc; Taylor, Michael D.; Handler, Michael; Foreman, Nicholas K.; Vibhakar, Rajeev

    2014-01-01

    Medulloblastoma is a pediatric brain tumor with a variable prognosis due to clinical and genomic heterogeneity. Among the 4 major genomic sub-groups, patients with MYC amplified tumors have a particularly poor prognosis despite therapy with surgery, radiation and chemotherapy. Targeting the MYC oncogene has traditionally been problematic. Here we report that MYC driven medulloblastoma can be targeted by inhibition of the bromodomain protein BRD4. We show that bromodomain inhibition with JQ1 r...

  18. T11TS inhibits Angiopoietin-1/Tie-2 signaling, EGFR activation and Raf/MEK/ERK pathway in brain endothelial cells restraining angiogenesis in glioma model.

    Science.gov (United States)

    Bhattacharya, Debanjan; Chaudhuri, Suhnrita; Singh, Manoj Kumar; Chaudhuri, Swapna

    2015-06-01

    Malignant gliomas represent one of the most aggressive and hypervascular primary brain tumors. Angiopoietin-1, the peptide growth factor activates endothelial Tie-2 receptor promoting vessel maturation and vascular stabilization steps of angiogenesis in glioma. Epidermal growth factor receptor (EGFR) and Tie-2 receptor on endothelial cells once activated transmits signals through downstream Raf/MEK/ERK pathway promoting endothelial cell proliferation and migration which are essential for angiogenesis induction. The in vivo effect of sheep erythrocyte membrane glycopeptide T11-target structure (T11TS) on angiopoietin-1/Tie-2 axis, EGFR signaling and Raf/MEK/ERK pathway in glioma associated endothelial cells has not been investigated previously. The present study performed with rodent glioma model aims to investigate the effect of T11TS treatment on angiopoietin-1/Tie-2 signaling, EGFR activity and Raf/MEK/ERK pathway in glioma associated endothelial cells within glioma milieu. T11TS administration in rodent glioma model inhibited angiopoietin-1 expression and attenuated Tie-2 expression and activation in glioma associated brain endothelial cells. T11TS treatment also downregulated total and phosphorylated EGFR expression in glioma associated endothelial cells. Additionally T11TS treatment inhibited Raf-1 expression, MEK-1 and ERK-1/2 expression and phosphorylation in glioma associated brain endothelial cells. Thus T11TS therapy remarkably inhibits endothelial angiopoietin-1/Tie-2 signaling associated with vessel maturation and simultaneously antagonizes endothelial cell proliferation signaling by blocking EGFR activation and components of Raf/MEK/ERK pathway. Collectively, the findings demonstrate a multi-targeted anti-angiogenic activity of T11TS which augments the potential for clinical translation of T11TS as an effective angiogenesis inhibitor for glioma treatment.

  19. Selective activation of p120ctn-Kaiso signaling to unlock contact inhibition of ARPE-19 cells without epithelial-mesenchymal transition.

    Science.gov (United States)

    Chen, Hung-Chi; Zhu, Ying-Ting; Chen, Szu-Yu; Tseng, Scheffer C G

    2012-01-01

    Contact-inhibition ubiquitously exists in non-transformed cells and explains the poor regenerative capacity of in vivo human retinal pigment epithelial cells (RPE) during aging, injury and diseases. RPE injury or degeneration may unlock mitotic block mediated by contact inhibition but may also promote epithelial-mesenchymal transition (EMT) contributing to retinal blindness. Herein, we confirmed that EMT ensued in post-confluent ARPE-19 cells when contact inhibition was disrupted with EGTA followed by addition of EGF and FGF-2 because of activation of canonical Wnt and Smad/ZEB signaling. In contrast, knockdown of p120-catenin (p120) unlocked such mitotic block by activating p120/Kaiso, but not activating canonical Wnt and Smad/ZEB signaling, thus avoiding EMT. Nuclear BrdU labeling was correlated with nuclear release of Kaiso through p120 nuclear translocation, which was associated with activation of RhoA-ROCK signaling, destabilization of microtubules. Prolonged p120 siRNA knockdown followed by withdrawal further expanded RPE into more compact monolayers with a normal phenotype and a higher density. This new strategy based on selective activation of p120/Kaiso but not Wnt/β-catenin signaling obviates the need of using single cells and the risk of EMT, and may be deployed to engineer surgical grafts containing RPE and other tissues. PMID:22590627

  20. Selective activation of p120ctn-Kaiso signaling to unlock contact inhibition of ARPE-19 cells without epithelial-mesenchymal transition.

    Directory of Open Access Journals (Sweden)

    Hung-Chi Chen

    Full Text Available Contact-inhibition ubiquitously exists in non-transformed cells and explains the poor regenerative capacity of in vivo human retinal pigment epithelial cells (RPE during aging, injury and diseases. RPE injury or degeneration may unlock mitotic block mediated by contact inhibition but may also promote epithelial-mesenchymal transition (EMT contributing to retinal blindness. Herein, we confirmed that EMT ensued in post-confluent ARPE-19 cells when contact inhibition was disrupted with EGTA followed by addition of EGF and FGF-2 because of activation of canonical Wnt and Smad/ZEB signaling. In contrast, knockdown of p120-catenin (p120 unlocked such mitotic block by activating p120/Kaiso, but not activating canonical Wnt and Smad/ZEB signaling, thus avoiding EMT. Nuclear BrdU labeling was correlated with nuclear release of Kaiso through p120 nuclear translocation, which was associated with activation of RhoA-ROCK signaling, destabilization of microtubules. Prolonged p120 siRNA knockdown followed by withdrawal further expanded RPE into more compact monolayers with a normal phenotype and a higher density. This new strategy based on selective activation of p120/Kaiso but not Wnt/β-catenin signaling obviates the need of using single cells and the risk of EMT, and may be deployed to engineer surgical grafts containing RPE and other tissues.

  1. Differential regulation of mTOR signaling determines sensitivity to AKT inhibition in diffuse large B cell lymphoma

    OpenAIRE

    Ezell, Scott A.; Wang, Suping; Bihani, Teeru; Lai, Zhongwu; Grosskurth, Shaun E.; Tepsuporn, Suprawee; Davies, Barry R; Huszar, Dennis; Byth, Kate F.

    2016-01-01

    Agents that target components of the PI3K/AKT/mTOR pathway are under investigation for the treatment of diffuse large B cell lymphoma (DLBCL). Given the highly heterogeneous nature of DLBCL, it is not clear whether all subtypes of DLBCL will be susceptible to PI3K pathway inhibition, or which kinase within this pathway is the most favorable target. Pharmacological profiling of a panel of DLBCL cell lines revealed a subset of DLBCL that was resistant to AKT inhibition. Strikingly, sensitivity ...

  2. Functional microarray analysis suggests repressed cell-cell signaling and cell survival-related modules inhibit progression of head and neck squamous cell carcinoma

    Directory of Open Access Journals (Sweden)

    Soares Fernando A

    2011-04-01

    Full Text Available Abstract Background Cancer shows a great diversity in its clinical behavior which cannot be easily predicted using the currently available clinical or pathological markers. The identification of pathways associated with lymph node metastasis (N+ and recurrent head and neck squamous cell carcinoma (HNSCC may increase our understanding of the complex biology of this disease. Methods Tumor samples were obtained from untreated HNSCC patients undergoing surgery. Patients were classified according to pathologic lymph node status (positive or negative or tumor recurrence (recurrent or non-recurrent tumor after treatment (surgery with neck dissection followed by radiotherapy. Using microarray gene expression, we screened tumor samples according to modules comprised by genes in the same pathway or functional category. Results The most frequent alterations were the repression of modules in negative lymph node (N0 and in non-recurrent tumors rather than induction of modules in N+ or in recurrent tumors. N0 tumors showed repression of modules that contain cell survival genes and in non-recurrent tumors cell-cell signaling and extracellular region modules were repressed. Conclusions The repression of modules that contain cell survival genes in N0 tumors reinforces the important role that apoptosis plays in the regulation of metastasis. In addition, because tumor samples used here were not microdissected, tumor gene expression data are represented together with the stroma, which may reveal signaling between the microenvironment and tumor cells. For instance, in non-recurrent tumors, extracellular region module was repressed, indicating that the stroma and tumor cells may have fewer interactions, which disable metastasis development. Finally, the genes highlighted in our analysis can be implicated in more than one pathway or characteristic, suggesting that therapeutic approaches to prevent tumor progression should target more than one gene or pathway

  3. Tetrandrine inhibits activation of rat hepatic stellate cells in vitro via transforming growth factor-β signaling

    Institute of Scientific and Technical Information of China (English)

    Yuan-Wen Chen; Jian-Xin Wu; Ying-Wei Chen; Ding-Guo Li; Han-Ming Lu

    2005-01-01

    AIM: To investigate the effect of various concentrations of tetrandrine on activation of quiescent rat hepatic stellate cells (HSCs) and transforming growth factor-β (TGF-β) signaling in vitro.METHODS: HSCs were isolated from rats by in situperfusion of liver and 18% Nycodenz gradient centrifugation, and primarily cultured on uncoated plastic plates for 24 hwith DMEM containing 20% fetal bovine serum (FBS/DMEM) before the culture medium was substituted with 2% FBS/DMEM for another 24 h. Then, the HSCs were cultured in 2% FBS/DMEM with tetrandrine (0.25, 0.5, 1,2 mg/L, respectively). Cell morphological features were observed under an inverted microscope, smooth muscleα-actin (α-SMA) was detected by immunocytochemistry and image analysis system, laminin (LN) and type Ⅲprocollagen (PCⅢ) in supernatants were determined byradioimmunoassay. TGF-β1 mRNA, Smad 7 mRNA and Smad 7 protein were analyzed with RT-PCR and Western blotting, respectively.RESULTS: Tetrandrine at the concentrations of 0.25-2 mg/L prevented morphological transformation of HSC from the quiescent state to the activated one, while α-SMA, LN and PCⅢ expressions were inhibited. As estimated by gray values, the expression of α-SMA in tetrandrine groups (0.25, 0.5, 1, 2 mg/L) was reduced from 21.3% to 42.2%(control: 0.67, tetrandrine groups: 0.82, 0.85, 0.96, or 0.96, respectively, which were statistically different from the control, P<0.01), and the difference was more significant in tetrandrine at 1 and 2 mg/L. The content of LN in supernatants was significantly decreased in tetrandrine groups to 58.5%, 69.1%, 65.8% or 60.0% that of the control respectively, and that of PCⅢ to 84.6%, 81.5%,75.7% or 80.7% respectively (P<0.05 vs control), with no significant difference among tetrandrine groups. RTPCR showed that TGF-β1 mRNA expression was reduced by tetrandrine treatments from 56.56% to 87.90% in comparison with the control, while Smad 7 mRNA was increased 1.4-4.8 times. The TGF-β1 m

  4. G protein-coupled receptor 30 ligand G-1 increases aryl hydrocarbon receptor signalling by inhibition of tubulin assembly and cell cycle arrest in human MCF-7 cells.

    Science.gov (United States)

    Tarnow, Patrick; Tralau, Tewes; Luch, Andreas

    2016-08-01

    Regulatory crosstalk between the aryl hydrocarbon receptor (AHR) and oestrogen receptor α (ERα) is well established. Apart from the nuclear receptors ERα and ERβ, oestrogen signalling further involves an unrelated G protein-coupled receptor termed GPR30. In order to investigate potential regulatory crosstalk, this study investigated the influence of G-1 as one of the few GPR30-specific ligands on the AHR regulon in MCF-7 cells. As a well-characterised model system, these human mammary carcinoma cells co-express all three receptors (AHR, ERα and GPR30) and are thus ideally suited to study corresponding regulatory pathway interactions on transcript level. Indeed, treatment with micromolar concentrations of the GPR30-specific agonist G-1 resulted in up-regulation of AHR as well as the transcripts for cytochromes P450 1A1 and 1B1, two well-known targets of the AHR regulon. While this was partly attributable to G-1-mediated inhibition of tubulin assembly and subsequent cell cycle arrest in the G2/M phase, the effects nevertheless required functional AHR. However, G-1-induced up-regulation of CYP 1A1 was not mediated by GPR30, as G15 antagonist treatment as well as a knockdown of GPR30 and AHR failed to inhibit this effect. PMID:26475489

  5. Nitric oxide from inflammatory origin impairs neural stem cell proliferation by inhibiting epidermal growth factor receptor signaling

    OpenAIRE

    Bruno Pereira Carreira; Maria Inês Morte; Ana Isabel Santos; Ana Sofia Lourenço; António Francisco Ambrósio; Carvalho, Caetana M.; Araújo, Inês M.

    2014-01-01

    Neuroinflammation is characterized by activation of microglial cells, followed by production of nitric oxide (NO), which may have different outcomes on neurogenesis, favoring or inhibiting this process. In the present study, we investigated how the inflammatory mediator NO can affect proliferation of neural stem cells (NSCs), and explored possible mechanisms underlying this effect. We investigated which mechanisms are involved in the regulation of NSC proliferation following treatment with an...

  6. A novel synthetic derivative of the natural product berbamine inhibits cell viability and induces apoptosis of human osteosarcoma cells, associated with activation of JNK/AP-1 signaling.

    Science.gov (United States)

    Yang, Fan; Nam, Sangkil; Zhao, Robin; Tian, Yan; Liu, Lucy; Horne, David A; Jove, Richard

    2013-11-01

    Osteosarcoma is the most common primary bone tumor in children and adolescents. There is a critical need to find more potent drugs for patients with metastatic or recurrent disease. Berbamine (BBM) is a natural compound derived from the Berberis amurensis plants. BBM and its derivatives have been shown to have antitumor effects in several cancers. Here, we report that a novel synthetic berbamine derivative, BBMD3, inhibits cell viability and induces apoptosis of G292, KHOS, and MG-63 human osteosarcoma cells. Induction of apoptosis in these tumor cells depends on activation of caspase-3 and cleavage of poly(ADP-ribose) polymerase (PARP). Since pan-caspase inhibitor (Z-VAD-FMK) and caspase-9 inhibitor (Z-LEHD-FMK) could block the cleavage of PARP, the apoptosis induced by BBMD3 is through intrinsic signaling pathway. BBMD3 increased phosphorylation of c-Jun N-terminal kinase (JNK)/stress-activated protein kinase (SAPK), resulting in increase of phosphorylated c-Jun and total c-Fos, the major components of transcriptional factor AP-1. JNK inhibitor could partially suppress antitumor effect of BBMD3 on osteosarcoma cells. BBMD3 increased the production of reactive oxygen species (ROS) and ROS scavenger, N-acetylcysteine (NAC), could block the phosphorylation of JNK and c-Jun induced by BBMD3. BBMD3 increased the expression of the pro-apototic gene Bad, associated with apoptosis induction. Finally, BBMD3 also decreased the expression of cyclin D1 and D2, the positive cell cycle regulators, which is correlated with growth inhibition in osteosarcoma cells. Collectively, these findings indicate that BBMD3 is a potentially promising drug for the treatment of human osteosarcoma. PMID:24025361

  7. Arsenic Trioxide Inhibits Cell Growth and Induces Apoptosis through Inactivation of Notch Signaling Pathway in Breast Cancer

    Directory of Open Access Journals (Sweden)

    Zhiwei Wang

    2012-08-01

    Full Text Available Arsenic trioxide has been reported to inhibit cell growth and induce apoptotic cell death in many human cancer cells including breast cancer. However, the precise molecular mechanisms underlying the anti-tumor activity of arsenic trioxide are still largely unknown. In the present study, we assessed the effects of arsenic trioxide on cell viability and apoptosis in breast cancer cells. For mechanistic studies, we used multiple cellular and molecular approaches such as MTT assay, apoptosis ELISA assay, gene transfection, RT-PCR, Western blotting, and invasion assays. For the first time, we found a significant reduction in cell viability in arsenic trioxide-treated cells in a dose-dependent manner, which was consistent with induction of apoptosis and also associated with down-regulation of Notch-1 and its target genes. Taken together, our findings provide evidence showing that the down-regulation of Notch-1 by arsenic trioxide could be an effective approach, to cause down-regulation of Bcl-2, and NF-κB, resulting in the inhibition of cell growth and invasion as well as induction of apoptosis. These results suggest that the anti-tumor activity of arsenic trioxide is in part mediated through a novel mechanism involving inactivation of Notch-1 and its target genes. We also suggest that arsenic trioxide could be further developed as a potential therapeutic agent for the treatment of breast cancer.

  8. Screening and identification of dietary oils and unsaturated fatty acids in inhibiting inflammatory prostaglandin E2 signaling in fat stromal cells

    Directory of Open Access Journals (Sweden)

    Ruan Diana

    2012-08-01

    Full Text Available Abstract Background The molecular mechanisms of dietary oils (such as fish oil and unsaturated fatty acids, which are widely used by the public for anti-inflammation and vascular protection, have not been settled yet. In this study, prostaglandin E2 (PGE2-mediated calcium signaling was used to screen dietary oils and eight unsaturated fatty acids for identification of their anti-inflammatory mechanisms. Isolated fat/stromal cells expressing endogenous PGE2 receptors and an HEK293 cell line specifically expressing the recombinant human PGE2 receptor subtype-1 (EP1 were cultured and used in live cell calcium signaling assays. The different dietary oils and unsaturated fatty acids were used to affect cell signaling under the specific stimulation of a pathological amount of inflammatory PGE2. Results It was identified that fish oil best inhibited the PGE2 signaling in the primary cultured stromal cells. Second, docosahexaenoic acid (DHA, found in abundance in fish oil, was identified as a key factor of inhibition of PGE2 signaling. Eicosapentaenoic acid (EPA, another major fatty acid found in fish oil and tested in this study was found to have small effect on EP1 signaling. The study suggested one of the four PGE2 subtype receptors, EP1 as the key target for the fish oil and DHA target. These findings were further confirmed by using the recombinant EP1 expressed in HEK293 cells as a target. Conclusion This study demonstrated the new mechanism behind the positive effects of dietary fish oils in inhibiting inflammation originates from the rich concentration of DHA, which can directly inhibit the inflammatory EP1-mediated PGE2 receptor signaling, and that the inflammatory response stimulated by PGE2 in the fat stromal cells, which directly related to metabolic diseases, could be down regulated by fish oil and DHA. These findings also provided direct evidence to support the use of dietary oils and unsaturated fatty acids for protection against heart

  9. A New Synthetic Ursolic Acid Derivative IUA with Anti-Tumor Efficacy Against Osteosarcoma Cells via Inhibition of JNK Signaling Pathway

    Directory of Open Access Journals (Sweden)

    Jian Chen

    2014-08-01

    Full Text Available Background: Osteosarcoma is the most common primary malignant bone tumor in children and adolescents and is characterized by frequent metastasis and resistance to chemotherapy. Because osteosarcoma cells are not highly susceptible to current chemotherapy drugs, new alternative strategies for the treatment of osteosarcoma are needed. This study was undertaken to investigate the inhibitory effects of a new synthetic ursolic acid derivative IUA on osteosarcoma cells and to explore its molecular mechanism. We also intended to identify new therapeutic candidates. Methods: We used MTT assay to assess the effect of IUA on the proliferation of osteosarcoma cells. Western-blot analysis was performed to examine downstream molecular events. The Annexin V method was used to evaluate the effect of IUA on apoptosis of osteosarcoma cells. The cell cycle of IUA-treated cells was examined by flow cytometry, and the in vivo effects of this new ursolic acid derivative were evaluated in a mouse osteosarcoma model. Results: The results showed that the new synthetic ursolic acid derivative IUA significantly decreased viability of osteosarcoma cells in vitro and in vivo. It could also induce apoptosis and G1 phase arrest of osteosarcoma cells. The JNK signaling pathway was significantly inhibited, and cleaved caspase-3 protein was increased. Conclusion: We concluded that the new synthetic ursolic acid derivative IUA induces proliferation inhibition and apoptosis of osteosarcoma cells in vitro and in vivo via the down-regulation of the JNK signaling pathway, making it a promising agent for the prevention and treatment of human osteosarcoma.

  10. Prolonged propagation of rat neural stem cells relies on inhibiting autocrine/paracrine bone morphogenetic protein and platelet derived growth factor signals

    Institute of Scientific and Technical Information of China (English)

    Yirui Sun; Liangfu Zhou; Xing Wu; Hua Liu; Qiang Yuan; Ying Mao; Jin Hu

    2011-01-01

    Continuous expansion of rat neural stem cell lines has not been achieved due to proliferation arrest and spontaneous differentiation in vitro. In the current study, neural precursor cells derived from the subventricular zone of adult rats spontaneously underwent astroglial and oligodendroglial differentiation after limited propagation. This differentiation was largely induced by autocrine or paracrine bone morphogenetic protein and platelet derived growth factor signals. The results showed that, by inhibiting bone morphogenetic protein and platelet derived growth factor signals, adult rat neural precursor cells could be extensively cultured in vitro as tripotent stem cell lines. In addition to adult rat neural stem cells, we found that bone morphogenetic protein antagonists can promote the proliferation of human neural stem cells. Therefore, the present findings illustrated the role of autocrine or paracrine bone morphogenetic protein and platelet derived growth factor signaling in determining neural stem cell self-renewal and differentiation. By antagonizing both signals, the long-term propagation of rat neural stem cell lines can be achieved.

  11. Kruppel-like factor 2 inhibit the angiogenesis of cultured human liver sinusoidal endothelial cells through the ERK1/2 signaling pathway

    International Nuclear Information System (INIS)

    Kruppel-like factor 2 (KLF2) is a crucial anti-angiogenic factor. However, its precise role in hepatic angiogenesis induced by liver sinusoidal endothelial cells (LSECs) remain unclear. This study was aimed to evaluate the effect of KLF2 on angiogenesis of LSECs and to explore the corresponding mechanism. Cultured human LSECs were infected with different lentiviruses to overexpress or suppress KLF2 expression. The CCK-8 assay, transwell migration assay and tube formation test, were used to investigate the roles of KLF2 in the proliferation, migration and vessel tube formation of LSECs, respectively. The expression and phosphorylation of ERK1/2 were detected by western blot. We discovered that the up-regulation of KLF2 expression dramatically inhibited proliferation, migration and tube formation in treated LSECs. Correspondingly, down-regulation of KLF2 expression significantly promoted proliferation, migration and tube formation in treated LSECs. Additionally, KLF2 inhibited the phosphorylation of ERK1/2 pathway, followed by the function of KLF2 in the angiogenesis of LSECs disrupted. In conclusion, KLF2 suppressed the angiogenesis of LSECs through inhibition of cell proliferation, migration, and vessel tube formation. These functions of KLF2 may be mediated through the ERK1/2 signaling pathway. - Highlights: • Overexpression of KLF2 inhibits the proliferation and migration of LSECs. • Overexpression of KLF2 inhibits the angiogenesis of LSECs. • ERK1/2 signaling pathway involved in the anti-angiogenic process of KLF2 on LSECs

  12. Kruppel-like factor 2 inhibit the angiogenesis of cultured human liver sinusoidal endothelial cells through the ERK1/2 signaling pathway

    Energy Technology Data Exchange (ETDEWEB)

    Zeng, Xiao-Qing, E-mail: zeng.xiaoqing@zs-hospital.sh.cn [Department of Gastroenterology of Zhongshan Hospital, Fudan University, Shanghai (China); Li, Na, E-mail: Linala.2009@163.com [Department of Gastroenterology of Zhongshan Hospital, Fudan University, Shanghai (China); Pan, Du-Yi, E-mail: lasikesmi@hotmail.com [Department of Gastroenterology of Zhongshan Hospital, Fudan University, Shanghai (China); Miao, Qing, E-mail: sadsadvenus@163.com [Department of Gastroenterology of Zhongshan Hospital, Fudan University, Shanghai (China); Ma, Gui-Fen, E-mail: ma.guifen@zs-hospital.sh.cn [Department of Gastroenterology of Zhongshan Hospital, Fudan University, Shanghai (China); Liu, Yi-Mei, E-mail: liuyimei1988@163.com [Department of Gastroenterology of Zhongshan Hospital, Fudan University, Shanghai (China); Tseng, Yu-Jen, E-mail: dianatseng14@gmail.com [Department of Gastroenterology of Zhongshan Hospital, Fudan University, Shanghai (China); Li, Feng, E-mail: li.feng2@zs-hospital.sh.cn [Department of Gastroenterology of Zhongshan Hospital, Fudan University, Shanghai (China); Xu, Li-Li, E-mail: xu.lili3@zs-hospital.sh.cn [Department of Gastroenterology of Zhongshan Hospital, Fudan University, Shanghai (China); Chen, Shi-Yao, E-mail: chen.shiyao@zs-hospital.sh.cn [Department of Gastroenterology of Zhongshan Hospital, Fudan University, Shanghai (China); Institute of Endoscopic Research of Zhongshan Hospital, Fudan University, Shanghai (China)

    2015-09-04

    Kruppel-like factor 2 (KLF2) is a crucial anti-angiogenic factor. However, its precise role in hepatic angiogenesis induced by liver sinusoidal endothelial cells (LSECs) remain unclear. This study was aimed to evaluate the effect of KLF2 on angiogenesis of LSECs and to explore the corresponding mechanism. Cultured human LSECs were infected with different lentiviruses to overexpress or suppress KLF2 expression. The CCK-8 assay, transwell migration assay and tube formation test, were used to investigate the roles of KLF2 in the proliferation, migration and vessel tube formation of LSECs, respectively. The expression and phosphorylation of ERK1/2 were detected by western blot. We discovered that the up-regulation of KLF2 expression dramatically inhibited proliferation, migration and tube formation in treated LSECs. Correspondingly, down-regulation of KLF2 expression significantly promoted proliferation, migration and tube formation in treated LSECs. Additionally, KLF2 inhibited the phosphorylation of ERK1/2 pathway, followed by the function of KLF2 in the angiogenesis of LSECs disrupted. In conclusion, KLF2 suppressed the angiogenesis of LSECs through inhibition of cell proliferation, migration, and vessel tube formation. These functions of KLF2 may be mediated through the ERK1/2 signaling pathway. - Highlights: • Overexpression of KLF2 inhibits the proliferation and migration of LSECs. • Overexpression of KLF2 inhibits the angiogenesis of LSECs. • ERK1/2 signaling pathway involved in the anti-angiogenic process of KLF2 on LSECs.

  13. Sargahydroquinoic acid inhibits TNFα-induced AP-1 and NF-κB signaling in HaCaT cells through PPARα activation

    Energy Technology Data Exchange (ETDEWEB)

    Jeon, Youngsic; Jung, Yujung; Kim, Min Cheol; Kwon, Hak Cheol [Natural Medicine Center, KIST Gangneung Institute, Gangneung 210-340 (Korea, Republic of); Kang, Ki Sung [College of Korean Medicine, Gachon University, Seongnam 461-701 (Korea, Republic of); Kim, Yong Kee, E-mail: yksnbk@sm.ac.kr [College of Pharmacy, Sookmyung Women’s University, Seoul 140-742 (Korea, Republic of); Kim, Su-Nam, E-mail: snkim@kist.re.kr [Natural Medicine Center, KIST Gangneung Institute, Gangneung 210-340 (Korea, Republic of)

    2014-08-08

    Highlights: • SHQA increases PPARα/γ transactivation and inhibits MMP-2/-9 expression. • SHQA inhibits TNFα-induced AP-1 and MAPK signaling. • SHQA inhibits TNFα-induced p65 translocation and IκBα phosphorylation. • SHQA inhibits TNFα-induced AP-1 and NF-κB signaling via PPARα. - Abstract: Peroxisome proliferator-activated receptors (PPARs) are members of the nuclear hormone receptor superfamily of ligand-activated transcription factors and expressed in various cell types in the skin, including keratinocytes, fibroblasts and infiltrating immune cells. Thus, their ligands are targets for the treatment of various skin disorders, such as photo-aging and chronological aging of skin. Intensive studies have revealed that PPARα/γ functions in photo-aging and age-related inflammation by regulating matrix metalloproteinases (MMPs) via activator protein-1 (AP-1) and nuclear factor kappa B (NF-κB). However, the detailed mechanism of PPARα/γ’s role in skin aging has not yet been elucidated. In this study, we confirmed that sargahydroquinoic acid (SHQA) as a PPARα/γ ligand significantly decreased Tumor Necrosis Factor-alpha (TNFα)-induced MMP-2/-9 expression by downregulating TNFα-induced transcription factors, subsequently reducing IκBα degradation and blocking NF-κB p65 nuclear translocation in HaCaT human epidermal keratinocyte cells. Treatment of cells with SHQA and GW6471 (PPARα antagonist) not bisphenol A diglycidyl ether (PPARγ antagonists), reversed the effect on TNFα-induced inflammatory signaling pathway activation. Taken together, our data suggest that SHQA inhibit TNFα-induced MMP-2/-9 expression and age-related inflammation by suppressing AP-1 and NF-κB pathway via PPARα.

  14. Oridonin inhibits gefitinib-resistant lung cancer cells by suppressing EGFR/ERK/MMP-12 and CIP2A/Akt signaling pathways.

    Science.gov (United States)

    Xiao, Xiangling; He, Zhongwei; Cao, Wei; Cai, Fen; Zhang, Liang; Huang, Qiuyue; Fan, Chunsheng; Duan, Chao; Wang, Xiaobo; Wang, Jiu; Liu, Ying

    2016-06-01

    Oridonin (Ori), a diterpenoid compound extracted from traditional medicinal herbs, elicits antitumor effects on many cancer types. However, whether Ori can be used in gefitinib-resistant non-small cell lung cancer (NSCLC) cells remains unclear. This study investigated the antitumor activity and underlying mechanisms of Ori. Results demonstrated that this compound dose-dependently inhibited the proliferation, invasion, and migration of the gefitinib-resistant NSCLC cells in vitro. Ori also significantly downregulated the phosphorylation of EGFR, ERK, Akt, expression levels of matrix metalloproteinase-12 (MMP-12), and the cancerous inhibitor of protein phosphatase 2A (CIP2A). In addition, Ori upregulated protein phosphatase 2A (PP2A) activity of gefitinib-resistant NSCLC cells. Ori combined with docetaxel synergistically inhibited these cells. Ori also inhibited tumor growth in murine models. Immunohistochemistry results further revealed that Ori downregulated phospho-EGFR, MMP-12, and CIP2A in vivo. These findings indicated that Ori can inhibit the proliferation, invasion, and migration of gefitinib-resistant NSCLC cells by suppressing EGFR/ERK/MMP-12 and CIP2A/PP2A/Akt signaling pathways. Thus, Ori may be a novel effective candidate to treat gefitinib-resistant NSCLC.

  15. Herbal Extract SH003 Suppresses Tumor Growth and Metastasis of MDA-MB-231 Breast Cancer Cells by Inhibiting STAT3-IL-6 Signaling

    OpenAIRE

    Youn Kyung Choi; Sung-Gook Cho; Sang-Mi Woo; Yee Jin Yun; Sunju Park; Yong Cheol Shin; Seong-Gyu Ko

    2014-01-01

    Cancer inflammation promotes cancer progression, resulting in a high risk of cancer. Here, we demonstrate that our new herbal extract, SH003, suppresses both tumor growth and metastasis of MDA-MB-231 breast cancer cells via inhibiting STAT3-IL-6 signaling path. Our new herbal formula, SH003, mixed extract from Astragalus membranaceus, Angelica gigas, and Trichosanthes kirilowii Maximowicz, suppressed MDA-MB-231 tumor growth and lung metastasis in vivo and reduced the viability and metastatic ...

  16. Metformin inhibits heme oxygenase-1 expression in cancer cells through inactivation of Raf-ERK-Nrf2 signaling and AMPK-independent pathways

    Energy Technology Data Exchange (ETDEWEB)

    Do, Minh Truong; Kim, Hyung Gyun; Khanal, Tilak; Choi, Jae Ho [Department of Toxicology, College of Pharmacy, Chungnam National University, Daejeon (Korea, Republic of); Kim, Dong Hee [Department of Pathology, College of Oriental Medicine, Daejeon University, Daejeon (Korea, Republic of); Jeong, Tae Cheon, E-mail: taecheon@ynu.ac.kr [College of Pharmacy, Yeungnam University, Gyeongsan (Korea, Republic of); Jeong, Hye Gwang, E-mail: hgjeong@cnu.ac.kr [Department of Toxicology, College of Pharmacy, Chungnam National University, Daejeon (Korea, Republic of)

    2013-09-01

    Resistance to therapy is the major obstacle to more effective cancer treatment. Heme oxygenase-1 (HO-1) is often highly up-regulated in tumor tissues, and its expression is further increased in response to therapies. It has been suggested that inhibition of HO-1 expression is a potential therapeutic approach to sensitize tumors to chemotherapy and radiotherapy. In this study, we tested the hypothesis that the anti-tumor effects of metformin are mediated by suppression of HO-1 expression in cancer cells. Our results indicate that metformin strongly suppresses HO-1 mRNA and protein expression in human hepatic carcinoma HepG2, cervical cancer HeLa, and non-small-cell lung cancer A549 cells. Metformin also markedly reduced Nrf2 mRNA and protein levels in whole cell lysates and suppressed tert-butylhydroquinone (tBHQ)-induced Nrf2 protein stability and antioxidant response element (ARE)-luciferase activity in HepG2 cells. We also found that metformin regulation of Nrf2 expression is mediated by a Keap1-independent mechanism and that metformin significantly attenuated Raf-ERK signaling to suppress Nrf2 expression in cancer cells. Inhibition of Raf-ERK signaling by PD98059 decreased Nrf2 mRNA expression in HepG2 cells, confirming that the inhibition of Nrf2 expression is mediated by an attenuation of Raf-ERK signaling in cancer cells. The inactivation of AMPK by siRNA, DN-AMPK or the pharmacological AMPK inhibitor compound C, revealed that metformin reduced HO-1 expression in an AMPK-independent manner. These results highlight the Raf-ERK-Nrf2 axis as a new molecular target in anticancer therapy in response to metformin treatment. - Highlights: • Metformin inhibits HO-1 expression in cancer cells. • Metformin attenuates Raf-ERK-Nrf2 signaling. • Suppression of HO-1 by metformin is independent of AMPK. • HO-1 inhibition contributes to anti-proliferative effects of metformin.

  17. Citrus aurantium flavonoids inhibit adipogenesis through the Akt signaling pathway in 3T3-L1 cells

    Directory of Open Access Journals (Sweden)

    Kim Gon-Sup

    2012-04-01

    Full Text Available Abstract Background Obesity is a health hazard that is associated with a number of diseases and metabolic abnormalities, such as type-2 diabetes, hypertension, dyslipidemia, and coronary heart disease. In the current study, we investigated the effects of Citrus aurantium flavonoids (CAF on the inhibition of adipogenesis and adipocyte differentiation in 3T3-L1 cells. Methods During adipocyte differentiation, 3T3-L1 cells were treated with 0, 10, and 50 μg/ml CAF, and then the mRNA and protein expression of adipogenesis-related genes was assayed. We examined the effect of CAF on level of phosphorylated Akt in 3T3-L1 cells treated with CAF at various concentrations during adipocyte differentiation. Results The insulin-induced expression of C/EBPβ and PPARγ mRNA and protein were significantly down-regulated in a dose-dependent manner following CAF treatment. CAF also dramatically decreased the expression of C/EBPα, which is essential for the acquisition of insulin sensitivity by adipocytes. Moreover, the expression of the aP2 and FAS genes, which are involved in lipid metabolism, decreased dramatically upon treatment with CAF. Interestingly, CAF diminished the insulin-stimulated serine phosphorylation of Akt (Ser473 and GSK3β (Ser9, which may reduce glucose uptake in response to insulin and lipid accumulation. Furthermore, CAF not only inhibited triglyceride accumulation during adipogenesis but also contributed to the lipolysis of adipocytes. Conclusions In the present study, we demonstrate that CAF suppressed adipogenesis in 3T3-L1 adipocytes. Our results indicated that CAF down-regulates the expression of C/EBPβ and subsequently inhibits the activation of PPARγ and C/EBPα. The anti-adipogenic activity of CAF was mediated by the inhibition of Akt activation and GSK3β phosphorylation, which induced the down-regulation of lipid accumulation and lipid metabolizing genes, ultimately inhibiting adipocyte differentiation.

  18. Radioactive 125I seeds inhibit cell growth and epithelial-mesenchymal transition in human glioblastoma multiforme via a ROS-mediated signaling pathway

    International Nuclear Information System (INIS)

    Glioblastoma multiforme (GBM) is the most common primary central nervous system neoplasm in adults. Radioactive 125I seed implantation has been widely applied in the treatment of cancers. Moreover, previous clinical trials have confirmed that 125I seeds treatment was an effective therapy in GBM. We sought to investigate the effect of 125I seed on GBM cell growth and Epithelial-mesenchymal transition (EMT). Cells were exposed to irradiation at different doses. Colony-formation assay, EdU assay, cell cycle analysis, and TUNEL assay were preformed to investigate the radiation sensitivity. The effects of 125I seeds irradiation on EMT were measured by transwell, Boyden and wound-healing assays. The levels of reactive oxygen species (ROS) were measured by DCF-DA assay. Moreover, the radiation sensitivity and EMT were investigated with or without pretreatment with glutathione. Additionally, nude mice with tumors were measured after treated with radiation. Radioactive 125I seeds are more effective than X-ray irradiation in inhibiting GBM cell growth. Moreover, EMT was effectively inhibited by 125I seed irradiation. A mechanism study indicated that GBM cell growth and EMT inhibition were induced by 125I seeds with the involvement of a ROS-mediated signaling pathway. Radioactive 125I seeds exhibit novel anticancer activity via a ROS-mediated signaling pathway. These findings have clinical implications for the treatment of patients with GBM by 125I seeds

  19. Dietary agent, benzyl isothiocyanate inhibits signal transducer and activator of transcription 3 phosphorylation and collaborates with sulforaphane in the growth suppression of PANC-1 cancer cells

    Directory of Open Access Journals (Sweden)

    Deangelis Stephanie

    2009-08-01

    Full Text Available Abstract The Signal Transducer and Activator of Transcription (STAT proteins comprise a family of latent transcription factors with diverse functions. STAT3 has well established roles in cell proliferation, growth and survival, and its persistent activation has been detected with high frequency in many human cancers. As constitutive activation of STAT3 appears to be vital for the continued survival of these cancerous cells, it has emerged as an attractive target for chemotherapeutics. We examined whether the inhibitory activities of bioactive compounds from cruciferous vegetables, such as Benzyl isothiocyanate (BITC and sulforaphane, extended to STAT3 activation in PANC-1 human pancreatic cancer cells. BITC and sulforaphane were both capable of inhibiting cell viability and inducing apoptosis in PANC-1. Sulforaphane had minimal effect on the direct inhibition of STAT3 tyrosine phosphorylation, however, suggesting its inhibitory activities are most likely STAT3-independent. Conversely, BITC was shown to inhibit the tyrosine phosphorylation of STAT3, but not the phosphorylation of ERK1/2, MAPK and p70S6 kinase. These results suggest that STAT3 may be one of the targets of BITC-mediated inhibition of cell viability in PANC-1 cancer cells. In addition, we show that BITC can prevent the induction of STAT3 activation by Interleukin-6 in MDA-MB-453 breast cancer cells. Furthermore, combinations of BITC and sulforaphane inhibited cell viability and STAT3 phosphorylation more dramatically than either agent alone. These findings suggest that the combination of the dietary agents BITC and sulforaphane has potent inhibitory activity in pancreatic cancer cells and that they may have translational potential as chemopreventative or therapeutic agents.

  20. Biphasic Role of Chondroitin Sulfate in Cardiac Differentiation of Embryonic Stem Cells through Inhibition of Wnt/beta-Catenin Signaling

    NARCIS (Netherlands)

    Prinz, R.D.; Willis, C.M.; Kuppevelt, T.H. van; Kluppel, M.

    2014-01-01

    The glycosaminoglycan chondroitin sulfate is a critical component of proteoglycans on the cell surface and in the extracellular matrix. As such, chondroitin sulfate side chains and the sulfation balance of chondroitin play important roles in the control of signaling pathways, and have a functional i

  1. OSU-A9 inhibits angiogenesis in human umbilical vein endothelial cells via disrupting Akt–NF-κB and MAPK signaling pathways

    Energy Technology Data Exchange (ETDEWEB)

    Omar, Hany A. [Division of Medicinal Chemistry, College of Pharmacy, The Ohio State University, Columbus, OH 43210 (United States); Department of Pharmacology, Faculty of Pharmacy, Beni-Suef University, Beni-Suef 62514 (Egypt); Arafa, El-Shaimaa A. [Department of Pharmacology, Faculty of Pharmacy, Beni-Suef University, Beni-Suef 62514 (Egypt); Salama, Samir A. [Department of Biochemistry, Faculty of Pharmacy, Al-Azhar University, Cairo 11511 (Egypt); Arab, Hany H. [Department of Biochemistry, Faculty of Pharmacy, Cairo University, Cairo 11562 (Egypt); Wu, Chieh-Hsi, E-mail: chhswu@mail.cmu.edu.tw [School of Pharmacy, China Medical University, Taichung 40402, Taiwan (China); Weng, Jing-Ru, E-mail: columnster@gmail.com [Department of Biological Science and Technology, China Medical University, Taichung 40402, Taiwan (China)

    2013-11-01

    Since the introduction of angiogenesis as a useful target for cancer therapy, few agents have been approved for clinical use due to the rapid development of resistance. This problem can be minimized by simultaneous targeting of multiple angiogenesis signaling pathways, a potential strategy in cancer management known as polypharmacology. The current study aimed at exploring the anti-angiogenic activity of OSU-A9, an indole-3-carbinol-derived pleotropic agent that targets mainly Akt–nuclear factor-kappa B (NF-κB) signaling which regulates many key players of angiogenesis such as vascular endothelial growth factor (VEGF) and matrix metalloproteinases (MMPs). Human umbilical vein endothelial cells (HUVECs) were used to study the in vitro anti-angiogenic effect of OSU-A9 on several key steps of angiogenesis. Results showed that OSU-A9 effectively inhibited cell proliferation and induced apoptosis and cell cycle arrest in HUVECs. Besides, OSU-A9 inhibited angiogenesis as evidenced by abrogation of migration/invasion and Matrigel tube formation in HUVECs and attenuation of the in vivo neovascularization in the chicken chorioallantoic membrane assay. Mechanistically, Western blot, RT-PCR and ELISA analyses showed the ability of OSU-A9 to inhibit MMP-2 production and VEGF expression induced by hypoxia or phorbol-12-myristyl-13-acetate. Furthermore, dual inhibition of Akt–NF-κB and mitogen-activated protein kinase (MAPK) signaling, the key regulators of angiogenesis, was observed. Together, the current study highlights evidences for the promising anti-angiogenic activity of OSU-A9, at least in part through the inhibition of Akt–NF-κB and MAPK signaling and their consequent inhibition of VEGF and MMP-2. These findings support OSU-A9's clinical promise as a component of anticancer therapy. - Highlights: • The antiangiogenic activity of OSU-A9 in HUVECs was explored. • OSU-A9 inhibited HUVECs proliferation, migration, invasion and tube formation. • OSU-A9

  2. Green tea polyphenol epigallocatechin-3-gallate inhibits TLR4 signaling through the 67-kDa laminin receptor on lipopolysaccharide-stimulated dendritic cells

    International Nuclear Information System (INIS)

    Highlights: ► Expressions of CD80, CD86, and MHC class I/II were inhibited by EGCG via 67LR. ► EGCG-treated DCs inhibited LPS-induced pro-inflammatory cytokines via 67LR. ► EGCG-treated DCs inhibited MAPKs activation and NF-κB p65 translocation via 67LR. ► EGCG elevated the expression of the Tollip protein through 67LR in DCs. -- Abstract: Epigallocatechin-3-gallate (EGCG), a major active polyphenol of green tea, has been shown to down-regulate inflammatory responses in dendritic cells (DCs); however, the underlying mechanism has not been understood. Recently, we identified the 67-kDa laminin receptor (67LR) as a cell-surface EGCG receptor. In this study, we showed the molecular basis for the down-regulation of toll-like receptor 4 (TLR4) signal transduction by EGCG in DCs. The expressions of CD80, CD86, and MHC class I and II, which are molecules essential for antigen presentation by DCs, were inhibited by EGCG via 67LR. In addition, EGCG-treated DCs inhibited lipopolysaccharide (LPS)-induced production of pro-inflammatory cytokines (tumor necrosis factor [TNF]-α, interleukin [IL]-1β, and IL-6) and activation of mitogen-activated protein kinases (MAPKs), e.g., extracellular signal-regulated kinase 1/2 (ERK1/2), p38, c-Jun N-terminal kinase (JNK), and nuclear factor κB (NF-κB) p65 translocation through 67LR. Interestingly, we also found that EGCG markedly elevated the expression of the Tollip protein, a negative regulator of TLR signaling, through 67LR. These novel findings provide new insight into the understanding of negative regulatory mechanisms of the TLR4 signaling pathway and consequent inflammatory responses that are implicated in the development and progression of many chronic diseases.

  3. Green tea polyphenol epigallocatechin-3-gallate inhibits TLR4 signaling through the 67-kDa laminin receptor on lipopolysaccharide-stimulated dendritic cells

    Energy Technology Data Exchange (ETDEWEB)

    Byun, Eui-Baek [Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup 580-185 (Korea, Republic of); Choi, Han-Gyu [Department of Microbiology and Research Institute for Medical Sciences, College of Medicine, Chungnam National University, Daejeon 301-747 (Korea, Republic of); Sung, Nak-Yun [Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup 580-185 (Korea, Republic of); Byun, Eui-Hong, E-mail: ehbyun80@gmail.com [Department of Microbiology and Research Institute for Medical Sciences, College of Medicine, Chungnam National University, Daejeon 301-747 (Korea, Republic of)

    2012-10-05

    Highlights: Black-Right-Pointing-Pointer Expressions of CD80, CD86, and MHC class I/II were inhibited by EGCG via 67LR. Black-Right-Pointing-Pointer EGCG-treated DCs inhibited LPS-induced pro-inflammatory cytokines via 67LR. Black-Right-Pointing-Pointer EGCG-treated DCs inhibited MAPKs activation and NF-{kappa}B p65 translocation via 67LR. Black-Right-Pointing-Pointer EGCG elevated the expression of the Tollip protein through 67LR in DCs. -- Abstract: Epigallocatechin-3-gallate (EGCG), a major active polyphenol of green tea, has been shown to down-regulate inflammatory responses in dendritic cells (DCs); however, the underlying mechanism has not been understood. Recently, we identified the 67-kDa laminin receptor (67LR) as a cell-surface EGCG receptor. In this study, we showed the molecular basis for the down-regulation of toll-like receptor 4 (TLR4) signal transduction by EGCG in DCs. The expressions of CD80, CD86, and MHC class I and II, which are molecules essential for antigen presentation by DCs, were inhibited by EGCG via 67LR. In addition, EGCG-treated DCs inhibited lipopolysaccharide (LPS)-induced production of pro-inflammatory cytokines (tumor necrosis factor [TNF]-{alpha}, interleukin [IL]-1{beta}, and IL-6) and activation of mitogen-activated protein kinases (MAPKs), e.g., extracellular signal-regulated kinase 1/2 (ERK1/2), p38, c-Jun N-terminal kinase (JNK), and nuclear factor {kappa}B (NF-{kappa}B) p65 translocation through 67LR. Interestingly, we also found that EGCG markedly elevated the expression of the Tollip protein, a negative regulator of TLR signaling, through 67LR. These novel findings provide new insight into the understanding of negative regulatory mechanisms of the TLR4 signaling pathway and consequent inflammatory responses that are implicated in the development and progression of many chronic diseases.

  4. An increase in galectin-3 causes cellular unresponsiveness to IFN-γ-induced signal transduction and growth inhibition in gastric cancer cells

    Science.gov (United States)

    Tseng, Po-Chun; Chen, Chia-Ling; Shan, Yan-Shen; Lin, Chiou-Feng

    2016-01-01

    Glycogen synthase kinase (GSK)-3β facilitates interferon (IFN)-γ signaling by inhibiting Src homology-2 domain-containing phosphatase (SHP) 2. Mutated phosphoinositide 3-kinase (PI3K) and phosphatase and tensin homolog (PTEN) cause AKT activation and GSK-3β inactivation to induce SHP2-activated cellular unresponsiveness to IFN-γ in human gastric cancer AGS cells. This study investigated the potential role of galectin-3, which acts upstream of AKT/GSK-3β/SHP2, in gastric cancer cells. Increasing or decreasing galectin-3 altered IFN-γ signaling. Following cisplatin-induced galectin-3 upregulation, surviving cells showed cellular unresponsiveness to IFN-γ. Galectin-3 induced IFN-γ resistance independent of its extracellular β-galactoside-binding activity. Galectin-3 expression was not regulated by PI3K activation or by a decrease in PTEN. Increased galectin-3 may cause GSK-3β inactivation and SHP2 activation by promoting PDK1-induced AKT phosphorylation at a threonine residue. Overexpression of AKT, inactive GSK-3βR96A, SHP2, or active SHP2D61A caused cellular unresponsiveness to IFN-γ in IFN-γ-sensitive MKN45 cells. IFN-γ-induced growth inhibition and apoptosis in AGS cells were observed until galectin-3 expression was downregulated. These results demonstrate that an increase in galectin-3 facilitates AKT/GSK-3β/SHP2 signaling, causing cellular unresponsiveness to IFN-γ. PMID:26934444

  5. N-3 poly-unsaturated fatty acids shift estrogen signaling to inhibit human breast cancer cell growth.

    Directory of Open Access Journals (Sweden)

    Wenqing Cao

    Full Text Available Although evidence has shown the regulating effect of n-3 poly-unsaturated fatty acid (n-3 PUFA on cell signaling transduction, it remains unknown whether n-3 PUFA treatment modulates estrogen signaling. The current study showed that docosahexaenoic acid (DHA, C22:6, eicosapentaenoic acid (EPA, C20:5 shifted the pro-survival and proliferative effect of estrogen to a pro-apoptotic effect in human breast cancer (BCa MCF-7 and T47D cells. 17 β-estradiol (E2 enhanced the inhibitory effect of n-3 PUFAs on BCa cell growth. The IC50 of DHA or EPA in MCF-7 cells decreased when combined with E2 (10 nM treatment (from 173 µM for DHA only to 113 µM for DHA+E2, and from 187 µm for EPA only to 130 µm for EPA+E2. E2 also augmented apoptosis in n-3 PUFA-treated BCa cells. In contrast, in cells treated with stearic acid (SA, C18:0 as well as cells not treated with fatty acid, E2 promoted breast cancer cell growth. Classical (nuclear estrogen receptors may not be involved in the pro-apoptotic effects of E2 on the n-3 PUFA-treated BCa cells because ERα agonist failed to elicit, and ERα knockdown failed to block E2 pro-apoptotic effects. Subsequent studies reveal that G protein coupled estrogen receptor 1 (GPER1 may mediate the pro-apoptotic effect of estrogen. N-3 PUFA treatment initiated the pro-apoptotic signaling of estrogen by increasing GPER1-cAMP-PKA signaling response, and blunting EGFR, Erk 1/2, and AKT activity. These findings may not only provide the evidence to link n-3 PUFAs biologic effects and the pro-apoptotic signaling of estrogen in breast cancer cells, but also shed new insight into the potential application of n-3 PUFAs in BCa treatment.

  6. Citrus aurantium flavonoids inhibit adipogenesis through the Akt signaling pathway in 3T3-L1 cells

    OpenAIRE

    Kim Gon-Sup; Park Hyoung Joon; Woo Jong-Hwa; Kim Mi-Kyeong; Koh Phil-Ok; Min Wongi; Ko Yeoung-Gyu; Kim Chung-Hei; Won Chung-Kil; Cho Jae-Hyeon

    2012-01-01

    Abstract Background Obesity is a health hazard that is associated with a number of diseases and metabolic abnormalities, such as type-2 diabetes, hypertension, dyslipidemia, and coronary heart disease. In the current study, we investigated the effects of Citrus aurantium flavonoids (CAF) on the inhibition of adipogenesis and adipocyte differentiation in 3T3-L1 cells. Methods During adipocyte differentiation, 3T3-L1 cells were treated with 0, 10, and 50 μg/ml CAF, and then the mRNA and protein...

  7. Ras-mutant cancer cells display B-Raf binding to Ras that activates extracellular signal-regulated kinase and is inhibited by protein kinase A phosphorylation.

    Science.gov (United States)

    Li, Yanping; Takahashi, Maho; Stork, Philip J S

    2013-09-20

    The small G protein Ras regulates proliferation through activation of the mitogen-activated protein (MAP) kinase (ERK) cascade. The first step of Ras-dependent activation of ERK signaling is Ras binding to members of the Raf family of MAP kinase kinase kinases, C-Raf and B-Raf. Recently, it has been reported that in melanoma cells harboring oncogenic Ras mutations, B-Raf does not bind to Ras and does not contribute to basal ERK activation. For other types of Ras-mutant tumors, the relative contributions of C-Raf and B-Raf are not known. We examined non-melanoma cancer cell lines containing oncogenic Ras mutations and express both C-Raf and B-Raf isoforms, including the lung cancer cell line H1299 cells. Both B-Raf and C-Raf were constitutively bound to oncogenic Ras and contributed to Ras-dependent ERK activation. Ras binding to B-Raf and C-Raf were both subject to inhibition by the cAMP-dependent protein kinase PKA. cAMP inhibited the growth of H1299 cells and Ras-dependent ERK activation via PKA. PKA inhibited the binding of Ras to both C-Raf and B-Raf through phosphorylations of C-Raf at Ser-259 and B-Raf at Ser-365, respectively. These studies demonstrate that in non-melanocytic Ras-mutant cancer cells, Ras signaling to B-Raf is a significant contributor to ERK activation and that the B-Raf pathway, like that of C-Raf, is a target for inhibition by PKA. We suggest that cAMP and hormones coupled to cAMP may prove useful in dampening the effects of oncogenic Ras in non-melanocytic cancer cells through PKA-dependent actions on B-Raf as well as C-Raf.

  8. Piperlongumine inhibits migration of glioblastoma cells via activation of ROS-dependent p38 and JNK signaling pathways.

    Science.gov (United States)

    Liu, Qian Rong; Liu, Ju Mei; Chen, Yong; Xie, Xiao Qiang; Xiong, Xin Xin; Qiu, Xin Yao; Pan, Feng; Liu, Di; Yu, Shang Bin; Chen, Xiao Qian

    2014-01-01

    Piperlongumine (PL) is recently found to kill cancer cells selectively and effectively via targeting reactive oxygen species (ROS) responses. To further explore the therapeutic effects of PL in cancers, we investigated the role and mechanisms of PL in cancer cell migration. PL effectively inhibited the migration of human glioma (LN229 or U87 MG) cells but not normal astrocytes in the scratch-wound culture model. PL did not alter EdU(+)-cells and cdc2, cdc25c, or cyclin D1 expression in our model. PL increased ROS (measured by DCFH-DA), reduced glutathione, activated p38 and JNK, increased IκBα, and suppressed NFκB in LN229 cells after scratching. All the biological effects of PL in scratched LN229 cells were completely abolished by the antioxidant N-acetyl-L-cysteine (NAC). Pharmacological administration of specific p38 (SB203580) or JNK (SP600125) inhibitors significantly reduced the inhibitory effects of PL on LN229 cell migration and NF κ B activity in scratch-wound and/or transwell models. PL prevented the deformation of migrated LN229 cells while NAC, SB203580, or SP600125 reversed PL-induced morphological changes of migrated cells. These results suggest potential therapeutic effects of PL in the treatment and prevention of highly malignant tumors such as glioblastoma multiforme (GBM) in the brain by suppressing tumor invasion and metastasis. PMID:24967005

  9. Piperlongumine Inhibits Migration of Glioblastoma Cells via Activation of ROS-Dependent p38 and JNK Signaling Pathways

    Directory of Open Access Journals (Sweden)

    Qian Rong Liu

    2014-01-01

    Full Text Available Piperlongumine (PL is recently found to kill cancer cells selectively and effectively via targeting reactive oxygen species (ROS responses. To further explore the therapeutic effects of PL in cancers, we investigated the role and mechanisms of PL in cancer cell migration. PL effectively inhibited the migration of human glioma (LN229 or U87 MG cells but not normal astrocytes in the scratch-wound culture model. PL did not alter EdU+-cells and cdc2, cdc25c, or cyclin D1 expression in our model. PL increased ROS (measured by DCFH-DA, reduced glutathione, activated p38 and JNK, increased IκBα, and suppressed NFκB in LN229 cells after scratching. All the biological effects of PL in scratched LN229 cells were completely abolished by the antioxidant N-acetyl-L-cysteine (NAC. Pharmacological administration of specific p38 (SB203580 or JNK (SP600125 inhibitors significantly reduced the inhibitory effects of PL on LN229 cell migration and NFκB activity in scratch-wound and/or transwell models. PL prevented the deformation of migrated LN229 cells while NAC, SB203580, or SP600125 reversed PL-induced morphological changes of migrated cells. These results suggest potential therapeutic effects of PL in the treatment and prevention of highly malignant tumors such as glioblastoma multiforme (GBM in the brain by suppressing tumor invasion and metastasis.

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

    Institute of Scientific and Technical Information of China (English)

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

    2008-01-01

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

  11. Grape seed extract inhibits EGF-induced and constitutively active mitogenic signaling but activates JNK in human prostate carcinoma DU145 cells: possible role in antiproliferation and apoptosis.

    Science.gov (United States)

    Tyagi, Alpana; Agarwal, Rajesh; Agarwal, Chapla

    2003-03-01

    A loss of functional androgen receptor and an enhanced expression of growth factor receptors and associated ligands are causal genetic events in prostate cancer (PCA) progression. These genetic alterations lead to an epigenetic mechanism where a feedback autocrine loop between membrane receptor and ligand (e.g. EGFR-TGFalpha) results in a constitutive activation of MAPK-Elk1-AP1-mediated mitogenic signaling in human PCA at an advanced and androgen-independent stage. We rationalized that inhibiting these epigenetic events could be useful in controlling advanced PCA growth. Recently, we found that grape seed extract (GSE), a dietary supplement rich in flavonoid procyanidins, inhibits advanced and androgen-independent human PCA DU145 cell growth in culture and nude mice. Here, we performed detailed mechanistic studies to define the effect of GSE on EGFR-Shc-MAPK-Elk1-AP1-mediated mitogenic signaling in DU145 cells. Pretreatment of serum-starved cells with GSE resulted in 70% to almost complete inhibition of EGF-induced EGFR activation and 50% to complete inhibition of Shc activation, which corroborated with a comparable decrease in EGF-induced Shc binding to EGFR. Conversely, EGF-induced ERK1/2 phosphorylation was inhibited only by lower doses of GSE; in fact, higher doses showed an increase. Additional studies showed that GSE alone causes a dose- and time-dependent increase in ERK1/2 phosphorylation in starved DU145 cells that is inhibited by an MEK1 inhibitor PD98059. Independent of this increase in ERK1/2 phosphorylation, GSE showed a strong inhibition of ERK1/2 kinase activity to Elk1 in both cellular and cell-free systems. GSE treatment of cells also inhibited both EGF-induced and constitutively active Elk1 phosphorylation and AP1 activation. GSE treatment also showed DNA synthesis inhibition in starved and EGF-stimulated cells as well as loss of cell viability and apoptotic death that was further increased by adding MEK1 inhibitor. Since GSE strongly induced

  12. 17-Beta-estradiol inhibits transforming growth factor-beta signaling and function in breast cancer cells via activation of extracellular signal-regulated kinase through the G protein-coupled receptor 30.

    Science.gov (United States)

    Kleuser, Burkhard; Malek, Daniela; Gust, Ronald; Pertz, Heinz H; Potteck, Henrik

    2008-12-01

    Breast cancer development and breast cancer progression involves the deregulation of growth factors leading to uncontrolled cellular proliferation, invasion and metastasis. Transforming growth factor (TGF)-beta plays a crucial role in breast cancer because it has the potential to act as either a tumor suppressor or a pro-oncogenic chemokine. A cross-communication between the TGF-beta signaling network and estrogens has been postulated, which is important for breast tumorigenesis. Here, we provide evidence that inhibition of TGF-beta signaling is associated with a rapid estrogen-dependent nongenomic action. Moreover, we were able to demonstrate that estrogens disrupt the TGF-beta signaling network as well as TGF-beta functions in breast cancer cells via the G protein-coupled receptor 30 (GPR30). Silencing of GPR30 in MCF-7 cells completely reduced the ability of 17-beta-estradiol (E2) to inhibit the TGF-beta pathway. Likewise, in GPR30-deficient MDA-MB-231 breast cancer cells, E2 achieved the ability to suppress TGF-beta signaling only after transfection with GPR30-encoding plasmids. It is most interesting that the antiestrogen fulvestrant (ICI 182,780), which possesses agonistic activity at the GPR30, also diminished TGF-beta signaling. Further experiments attempted to characterize the molecular mechanism by which activated GPR30 inhibits the TGF-beta pathway. Our results indicate that GPR30 induces the stimulation of the mitogen-activated protein kinases (MAPKs), which interferes with the activation of Smad proteins. Inhibition of MAPK activity prevented the ability of E2 from suppressing TGF-beta signaling. These findings are of great clinical relevance, because down-regulation of TGF-beta signaling is associated with the development of breast cancer resistance in response to antiestrogens.

  13. Inhibition of the STAT3 signaling pathway is involved in the antitumor activity of cepharanthine in SaOS2 cells

    Institute of Scientific and Technical Information of China (English)

    Zan CHEN; Chen HUANG; Yan-ling YANG; Yi DING; Han-qiang; OU-YANG; You-yi ZHANG; Ming XU

    2012-01-01

    To investigate the molecular mechanisms underlying the antitumor activity of cepharanthine (CEP),an alkaloid extracted from Stephania cepharantha Hayata.Methods:Human osteosarcoma cell line SaOS2 was used.MTT assay,Hoechst 33342 nuclear staining,flow cytometry,Western blotting and nude mouse xenografts of SaOS2 cells were applied to examine the antitumor activity of CEP in vitro and in vivo.The expression levels of STAT3 and its downstream signaling molecules were measured with Western blotting and immunochemistry analysis.The activity of STAT3 was detected based on the phosphorylation level of STAT3,luciferase gene reporter assay and translocation of STAT3 to the nucleus.Results:Treatment of SaOS2 cells with CEP (2.5-20 μmol/L) inhibited the cell growth in a concentration- and time-dependent manner.CEP (10 μmol/L) caused cell cycle arrest at G1 phase and induced apoptosis of SaOS2 cells.CEP (10 and 15 μmol/L) significantly decreased the expression of STAT3 in SaOS2 cells.Furthermore,CEP (5 and 10 μmol/L) significantly inhibited the expression of target genes of STAT3,including the anti-apoptotic gene Bcl-xL and the cell cycle regulators c-Myc and cyclin D1.In nude mouse xenografts of SaOS2 cells,CEP (20 mg·kg-1-d-1,ip for 19 d) significantly reduced the volume and weight of the tumor.Conclusion:Our findings suggest that inhibition of STAT3 signaling pathway is involved in the anti-tumor activity of CEP.

  14. MEK1/2 inhibition enhances the radiosensitivity of cancer cells by downregulating survival and growth signals mediated by EGFR ligands.

    Science.gov (United States)

    Chung, Eun Joo; Urick, Mary Ellen; Kurshan, Naamit; Shield, William; Asano, Hiroaki; Smith, Paul D; Scroggins, Bradley S; Burkeen, Jeffrey; Citrin, Deborah E

    2013-06-01

    The inhibition of the Ras/mitogen-activated protein kinase (Ras/MAPK) pathway through the suppression of mutated Ras or MAPK/extracellular signal-regulated kinase 1/2 (MEK1/2) has been shown to sensitize tumor cells to ionizing radiation (IR). The molecular mechanisms of this sensitization however, are not yet fully understood. In this study, we investigated the role of transforming growth factor-α (TGF-α) in the radiosensitizing effects of selumetinib, a selective inhibitor of MEK1/2. The expression of epidermal growth factor receptor (EGFR) ligands was assessed by ELISA in both Ras wild-type and Ras mutant cells that were exposed to radiation with or without selumetinib. The effects of selumetinib on the TGF-α/EGFR signaling cascade in response to radiation were examined by western blot analysis, clonogenic assay and by determing the yield of mitotic catastrophe. The treatment of cells with selumetinib reduced the basal and IR-induced secretion of TGF-α in both Ras wild-type and Ras mutant cell lines in vitro and in vivo. The reduction of TGF-α secretion was accompanied with a reduction in phosphorylated tumor necrosis factor-α converting enzyme (TACE) in the cells treated with selumetinib with or without IR. The treatment of cells with selumetinib with or without IR inhibited the phosphorylation of EGFR and checkpoint kinase 2 (Chk2), and reduced the expression of survivin. Supplementation with exogenous TGF-α partially rescued the selumetinib-treated cells from IR-induced cell death, restored EGFR and Chk2 phosphorylation and increased survivin expression. These data suggest that the inhibition of MEK1/2 with selumetinib may provide a mechanism to sensitize tumor cells to IR in a fashion that prevents the activation of the TGF-α autocrine loop following IR.

  15. Short-Chain Fatty Acids Inhibit Growth Hormone and Prolactin Gene Transcription via cAMP/PKA/CREB Signaling Pathway in Dairy Cow Anterior Pituitary Cells

    Directory of Open Access Journals (Sweden)

    Jian-Fa Wang

    2013-10-01

    Full Text Available Short-chain fatty acids (SCFAs play a key role in altering carbohydrate and lipid metabolism, influence endocrine pancreas activity, and as a precursor of ruminant milk fat. However, the effect and detailed mechanisms by which SCFAs mediate bovine growth hormone (GH and prolactin (PRL gene transcription remain unclear. In this study, we detected the effects of SCFAs (acetate, propionate, and butyrate on the activity of the cAMP/PKA/CREB signaling pathway, GH, PRL, and Pit-1 gene transcription in dairy cow anterior pituitary cells (DCAPCs. The results showed that SCFAs decreased intracellular cAMP levels and a subsequent reduction in PKA activity. Inhibition of PKA activity decreased CREB phosphorylation, thereby inhibiting GH and PRL gene transcription. Furthermore, PTX blocked SCFAs- inhibited cAMP/PKA/CREB signaling pathway. These data showed that the inhibition of GH and PRL gene transcription induced by SCFAs is mediated by Gi activation and that propionate is more potent than acetate and butyrate in inhibiting GH and PRL gene transcription. In conclusion, this study identifies a biochemical mechanism for the regulation of SCFAs on bovine GH and PRL gene transcription in DCAPCs, which may serve as one of the factors that regulate pituitary function in accordance with dietary intake.

  16. IL-1 beta-induced chemokine and Fas expression are inhibited by suppressor of cytokine signalling-3 in insulin-producing cells

    DEFF Research Database (Denmark)

    Jacobsen, M.L.B.; Ronn, S.G.; Bruun, C.;

    2009-01-01

    of genes encoding the Fas receptor and several chemokines. We have previously shown that suppressor of cytokine signalling (SOCS)-3 inhibits IL-1 beta- and IFN-gamma-induced nitric oxide production in a beta cell line. The aim of this study was to investigate whether SOCS-3 can influence cytokine......Chemokines recruit activated immune cells to sites of inflammation and are important mediators of insulitis. Activation of the pro-apoptotic receptor Fas leads to apoptosis-mediated death of the Fas-expressing cell. The pro-inflammatory cytokines IL-1 beta and IFN-gamma regulate the transcription......-induced Fas and chemokine expression in beta cells. Using a beta cell line with inducible Socs3 expression or primary neonatal rat islet cells transduced with a Socs3-encoding adenovirus, we employed real-time RT-PCR analysis to investigate whether SOCS-3 affects cytokine-induced chemokine and Fas m...

  17. IL-1beta-induced chemokine and Fas expression are inhibited by suppressor of cytokine signalling-3 in insulin-producing cells

    DEFF Research Database (Denmark)

    Jacobsen, M L B; Rønn, S G; Bruun, C;

    2008-01-01

    the transcription of genes encoding the Fas receptor and several chemokines. We have previously shown that suppressor of cytokine signalling (SOCS)-3 inhibits IL-1beta- and IFN-gamma-induced nitric oxide production in a beta cell line. The aim of this study was to investigate whether SOCS-3 can influence cytokine......AIMS/HYPOTHESIS: Chemokines recruit activated immune cells to sites of inflammation and are important mediators of insulitis. Activation of the pro-apoptotic receptor Fas leads to apoptosis-mediated death of the Fas-expressing cell. The pro-inflammatory cytokines IL-1beta and IFN-gamma regulate......-induced Fas and chemokine expression in beta cells. METHODS: Using a beta cell line with inducible Socs3 expression or primary neonatal rat islet cells transduced with a Socs3-encoding adenovirus, we employed real-time RT-PCR analysis to investigate whether SOCS-3 affects cytokine-induced chemokine and Fas m...

  18. Matrine induces the hepatic differentiation of WB-F344 rat hepatic progenitor cells and inhibits Jagged 1/HES1 signaling.

    Science.gov (United States)

    Yang, Zhiyun; Wang, Li; Wang, Xianbo

    2016-10-01

    Matrine is a Chinese medicine, which is widely utilized for the attenuation of liver injuries and promotion of liver regeneration. It was previously observed that the in vivo administration of matrine promoted oval cell‑mediated liver regeneration in a rat model, suggesting that this compound may affect the differentiation of hepatic progenitor cells. The present study aimed to determine the mechanisms underlying this observation and to investigate the effect of matrine on the differentiation of the WB‑F344 rat hepatic progenitor cell line. Matrine was administered to rats, and rat serum was collected. WB‑F344 cells were cultured in the presence or absence of the rat serum for 24‑72 h, and the effects on cell viability and proliferation were assessed using acridine orange/propidium iodide staining and a 3‑(4,5‑dimethylthiazol‑2‑yl) ‑2,5‑diphenyltetrazolium bromide assay. The expression of albumin (ALB, a hepatocyte marker) and the notch signaling pathway ligand, Jagged 1, were assessed using immunohistochemistry and western blotting, and the mRNA transcription of ALB, Jagged 1 and hairy and enhancer of split‑1 (HES1, another notch signaling ligand) were measured using reverse transcription‑polymerase chain reaction analysis. The results showed that proliferation of the WB‑F344 cells was inhibited by matrine serum in a concentration‑ and time‑dependent manner. Matrine serum downregulated Jagged 1 and HES1, and upregulated ALB, indicating the induction of WB‑F344 cell differentiation. The effects of matrine serum were reversed by supplementing the culture medium with 0.1 mol/l parathyroid hormone, a Notch signaling pathway activator. In conclusion, matrine induced hepatic differentiation of the hepatic progenitor cells, likely by inhibiting the Jagged 1/HES1 signaling pathway.

  19. Resveratrol Inhibits the Invasion of Glioblastoma-Initiating Cells via Down-Regulation of the PI3K/Akt/NF-κB Signaling Pathway

    Directory of Open Access Journals (Sweden)

    Yuming Jiao

    2015-06-01

    Full Text Available Invasion and metastasis of glioblastoma-initiating cells (GICs are thought to be responsible for the progression and recurrence of glioblastoma multiforme (GBM. A safe drug that can be applied during the rest period of temozolomide (TMZ maintenance cycles would greatly improve the prognosis of GBM patients by inhibiting GIC invasion. Resveratrol (RES is a natural compound that exhibits anti-invasion properties in multiple tumor cell lines. The current study aimed to evaluate whether RES can inhibit GIC invasion in vitro and in vivo. GICs were identified using CD133 and Nestin immunofluorescence staining and tumorigenesis in non-obese diabetic severe combined immunodeficient (NOD/SCID mice. Invasive behaviors, including the adhesion, invasion and migration of GICs, were determined by tumor invasive assays in vitro and in vivo. The activity of matrix metalloproteinases (MMPs was measured by the gelatin zymography assay. Western blotting analysis and immunofluorescence staining were used to determine the expression of signaling effectors in GICs. We demonstrated that RES suppressed the adhesion, invasion and migration of GICs in vitro and in vivo. Moreover, we proved that RES inhibited the invasion of GICs via the inhibition of PI3K/Akt/NF-κB signal transduction and the subsequent suppression of MMP-2 expression.

  20. Inhibition of protein kinase B by Palmitate in the insulin signaling of HepG2 cells and the preventive effect of Arachidonic acid on insulin resistance

    Institute of Scientific and Technical Information of China (English)

    XIA Yanzhi; WAN Xuedong; DUAN Qiuhong; HE Shansu; WANG Ximing

    2007-01-01

    Elevated plasma levels of free fatty acids(FFAs)may contribute to insulin resistance (IR)that is characteristic of type 2 diabetes mellitus.In this study,we investigated the effects of two fatty acids,palmitate(PA)and arachidonic acid (AA)on glycogenesis under insulin signaling in HepG2cells,a transformed hepatic carcinoma cell line.In the presence of 200 μmol of palmitate,insulin(10-7 mol/L)stimulation of glycogenesis was inhibited,as evidenced by increased glucose in the medium and decreased intracellular glycogen.Wortmannin(WM),a specific inhibitor of PI3K,dramatically decreased the amount of intracellular glycogen in cells without PA incubation.However,glycogen in PA treated cells was not significantly changed by WM,indicating that PA may also act on PI3K.Interestingly,AA restored the effects of WM inhibition on glycogenesis in PA cells.Western blot analysis demonstrated that PA in the absence of WM increased phosphorylated glycogen synthase(inactive form of GS)and decreased phosphorylated protein kinase B(active form of PKB),causing a reduction of intracellular glycogen.AA,however,reversed the effects of PA on GS and PKB.Furthermore,inhibition of protein kinase C(PKC)by a specific inhibitor chelerythrine chloride (CC)abolished the inhibitory efrect of PA on glycogen synthesis by decreasing phosphorylated GS and increasing phosphorylated PKB.However,the effect of CC in the presence of PA disappeared when AA was also present.Our results suggest that there is a disruption of the insulin signaling pathway between PKB and GS when the cells were exposed to PA,contributing to IR.PA may also interrupt the PKC signaling pathway.In contrast,AA could rescue glycogenesis impaired by PA.

  1. Methylcobalamin promotes proliferation and migration and inhibits apoptosis of C2C12 cells via the Erk1/2 signaling pathway

    Energy Technology Data Exchange (ETDEWEB)

    Okamoto, Michio [Department of Orthopaedic Surgery, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka 565-0871 (Japan); Tanaka, Hiroyuki, E-mail: tanahiro-osk@umin.ac.jp [Department of Orthopaedic Surgery, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka 565-0871 (Japan); Okada, Kiyoshi [Department of Orthopaedic Surgery, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka 565-0871 (Japan); Kuroda, Yusuke [Department of Orthopaedic Surgery, Kansai Rosai Hospital, 3-1-69 Inabaso, Amagasaki, Hyogo 660-8511 (Japan); Nishimoto, Shunsuke; Murase, Tsuyoshi; Yoshikawa, Hideki [Department of Orthopaedic Surgery, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka 565-0871 (Japan)

    2014-01-17

    Highlights: •Methylcobalamin activated the Erk1/2 signaling pathway in C2C12 cells. •Methylcobalamin promoted the proliferation and migration in C2C12 cells. •C2C12 cell apoptosis during differentiation was inhibited by methylcobalamin. -- Abstract: Methylcobalamin (MeCbl) is a vitamin B12 analog that has some positive effects on peripheral nervous disorders. Although some previous studies revealed the effects of MeCbl on neurons, its effect on the muscle, which is the final target of motoneuron axons, remains to be elucidated. This study aimed to determine the effect of MeCbl on the muscle. We found that MeCbl promoted the proliferation and migration of C2C12 myoblasts in vitro and that these effects are mediated by the Erk1/2 signaling pathway without affecting the activity of the Akt signaling pathway. We also demonstrated that MeCbl inhibits C2C12 cell apoptosis during differentiation. Our results suggest that MeCbl has beneficial effects on the muscle in vitro. MeCbl administration may provide a novel therapeutic approach for muscle injury or degenerating muscle after denervation.

  2. Inhibition of breast cancer cell motility with a non-cyclooxygenase inhibitory derivative of sulindac by suppressing TGFβ/miR-21 signaling.

    Science.gov (United States)

    Yi, Bin; Chang, Hong; Ma, Ruixia; Feng, Xiangling; Li, Wei; Piazza, Gary A; Xi, Yaguang

    2016-02-16

    Compelling efficacy on intervention of tumorigenesis by nonsteroidal anti-inflammatory drugs (NSAIDs) has been documented intensively. However, the toxicities related to cyclooxygenase (COX) inhibition resulting in suppression of physiologically important prostaglandins limit their clinical use for human cancer chemoprevention. A novel derivative of the NSAID sulindac sulfide (SS), referred as sulindac sulfide amide (SSA), was recently developed, which lacks COX inhibitory activity, yet shows greater suppressive effect than SS on growth of various cancer cells. In this study, we focus on the inhibitory activity of SSA on breast tumor cell motility, which has not been studied previously. Our results show that SSA treatment at non-cytotoxic concentrations can specifically reduce breast tumor cell motility without influencing tumor cell growth, and the mechanism of action involves the suppression of TGFβ signaling by directly blocking Smad2/3 phosphorylation. Moreover, miR-21, a well-documented oncogenic miRNA for promoting tumor cell metastasis, was also found to be involved in inhibitory activity of SSA in breast tumor cell motility through the modulation of TGFβ pathway. In conclusion, we demonstrate that a non-COX inhibitory derivative of sulindac can inhibit breast tumor metastasis by a mechanism involving the TGFβ/miR-21 signaling axis.

  3. Resveratrol inhibits the expression of SREBP1 in cell model of steatosis via Sirt1-FOXO1 signaling pathway.

    Science.gov (United States)

    Wang, Guang-Li; Fu, Yu-Cai; Xu, Wen-Can; Feng, Ya-Qing; Fang, Shi-Rong; Zhou, Xiao-Hui

    2009-03-13

    Recent studies in mice have shown that resveratrol can protect the liver from fat accumulation induced by high fat diet. However, the exact mechanism is largely unknown. To explore the possible mechanism, we investigated the anti-lipogenic effect of resveratrol in vitro model. Oil Red O staining revealed that resveratrol could significantly ameliorate the excessive triglyceride accumulation in HepG2 cells induced by palmitate. The results of RT-PCR and Western blotting showed that resveratrol upregulated the expression of Sirt1 and forkhead box O1 (FOXO1), whereas downregulated the expression of sterol regulatory element binding protein1 (SREBP1). Moreover, resveratrol was shown to inhibit the activity of SREBP1, as evaluated by immunofluorescence assay. Our results suggest that resveratrol may attenuate fat deposition by inhibiting SREBP1 expression via Sirt1-FOXO1 pathway and thus may have application for the treatment of NAFLD. PMID:19285015

  4. Pharmacological Inhibition of Protein Kinase G1 Enhances Bone Formation by Human Skeletal Stem Cells Through Activation of RhoA-Akt Signaling

    DEFF Research Database (Denmark)

    Kermani, Abbas Jafari; Siersbaek, Majken S; Chen, Li;

    2015-01-01

    Development of novel approaches to enhance bone regeneration is needed for efficient treatment of bone defects. Protein kinases play a key role in regulation of intracellular signal transduction pathways, and pharmacological targeting of protein kinases has led to development of novel treatments...... for several malignant and nonmalignant conditions. We screened a library of kinase inhibitors to identify small molecules that enhance bone formation by human skeletal (stromal or mesenchymal) stem cells (hMSC). We identified H-8 (known to inhibit protein kinases A, C, and G) as a potent enhancer of ex vivo...... functional screening of known H-8 targets, we demonstrated that inhibition of protein kinase G1 (PRKG1) and consequent activation of RhoA-Akt signaling is the main mechanism through which H-8 enhances osteogenesis. Our studies revealed PRKG1 as a novel negative regulator of OB differentiation and suggest...

  5. S100A7-downregulation inhibits epidermal growth factor-induced signaling in breast cancer cells and blocks osteoclast formation.

    Directory of Open Access Journals (Sweden)

    Vikram Paruchuri

    Full Text Available S100A7 is a small calcium binding protein, which has been shown to be differentially expressed in psoriatic skin lesions, as well as in squamous cell tumors of the skin, lung and breast. Although its expression has been correlated to HER+ high-grade tumors and to a high risk of progression, the molecular mechanisms of these S100A7-mediated tumorigenic effects are not well known. Here, we showed for the first time that epidermal growth factor (EGF induces S100A7 expression in both MCF-7 and MDA-MB-468 cell lines. We also observed a decrease in EGF-directed migration in shRNA-downregulated MDA-MB-468 cell lines. Furthermore, our signaling studies revealed that EGF induced simultaneous EGF receptor phosphorylation at Tyr1173 and HER2 phosphorylation at Tyr1248 in S100A7-downregulated cell lines as compared to the vector-transfected controls. In addition, reduced phosphorylation of Src at tyrosine 416 and p-SHP2 at tyrosine 542 was observed in these downregulated cell lines. Further studies revealed that S100A7-downregulated cells had reduced angiogenesis in vivo based on matrigel plug assays. Our results also showed decreased tumor-induced osteoclastic resorption in an intra-tibial bone injection model involving SCID mice. S100A7-downregulated cells had decreased osteoclast number and size as compared to the vector controls, and this decrease was associated with variations in IL-8 expression in in vitro cell cultures. This is a novel report on the role of S100A7 in EGF-induced signaling in breast cancer cells and in osteoclast formation.

  6. PLCε knockdown inhibits prostate cancer cell proliferation via suppression of Notch signalling and nuclear translocation of the androgen receptor.

    Science.gov (United States)

    Wang, Yin; Wu, Xiaohou; Ou, Liping; Yang, Xue; Wang, Xiaorong; Tang, Min; Chen, E; Luo, Chunli

    2015-06-28

    Phospholipase Cε (PLCε), a key regulator of diverse cellular functions, has been implicated in various malignancies. Indeed, PLCε functions include cell proliferation, apoptosis and malignant transformation. Here, we show that PLCε expression is elevated in prostate cancer (PCa) tissues compared to benign prostate tissues. Furthermore, PLCε depletion using an adenovirally delivered shRNA significantly decreased cell growth and colony formation, arresting the PC3 and LNCaP cell lines in the S phase of the cell cycle. We also observed that PLCε was significantly correlated with Notch1 and androgen receptor (AR). Additionally, we demonstrate that the activation of both the Notch and AR signalling pathways is involved in PLCε-mediated oncogenic effects in PCa. Our findings suggest that PLCε is a putative oncogene and prognostic marker, potentially representing a novel therapeutic target for PCa.

  7. Glioma Cell Migration on Three-dimensional Nanofiber Scaffolds Is Regulated by Substrate Topography and Abolished by Inhibition of STAT3 Signaling

    Directory of Open Access Journals (Sweden)

    Paula A. Agudelo-Garcia

    2011-09-01

    Full Text Available A hallmark of malignant gliomas is their ability to disperse through neural tissue, leading to long-term failure of all known therapies. Identifying new antimigratory targets could reduce glioma recurrence and improve therapeutic efficacy, but screens based on conventional migration assays are hampered by the limited ability of these assays to reproduce native cell motility. Here, we have analyzed the motility, gene expression, and sensitivity to migration inhibitors of glioma cells cultured on scaffolds formed by submicron-sized fibers (nanofibers mimicking the neural topography. Glioma cells cultured on aligned nanofiber scaffolds reproduced the elongated morphology of cells migrating in white matter tissue and were highly sensitive to myosin II inhibition but only moderately affected by stress fiber disruption. In contrast, the same cells displayed a flat morphology and opposite sensitivity to myosin II and actin inhibition when cultured on conventional tissue culture polystyrene. Gene expression analysis indicated a correlation between migration on aligned nanofibers and increased STAT3 signaling, a known driver of glioma progression. Accordingly, cell migration out of glioblastoma-derived neurospheres and tumor explants was reduced by STAT3 inhibitors at subtoxic concentrations. Remarkably, these inhibitors were ineffective when tested at the same concentrations in a conventional two-dimensional migration assay. We conclude that migration of glioma cells is regulated by topographical cues that affect cell adhesion and gene expression. Cell migration analysis using nanofiber scaffolds could be used to reproduce native mechanisms of migration and to identify antimigratory strategies not disclosed by other in vitro models.

  8. Immunoglobulin E signal inhibition during allergen ingestion leads to reversal of established food allergy and induction of regulatory T cells.

    Science.gov (United States)

    Burton, Oliver T; Noval Rivas, Magali; Zhou, Joseph S; Logsdon, Stephanie L; Darling, Alanna R; Koleoglou, Kyle J; Roers, Axel; Houshyar, Hani; Crackower, Michael A; Chatila, Talal A; Oettgen, Hans C

    2014-07-17

    Immunoglobulin E (IgE) antibodies are known for triggering immediate hypersensitivity reactions such as food anaphylaxis. In this study, we tested whether they might additionally function to amplify nascent antibody and T helper 2 (Th2) cell-mediated responses to ingested proteins and whether blocking IgE would modify sensitization. By using mice harboring a disinhibited form of the IL-4 receptor, we developed an adjuvant-free model of peanut allergy. Mast cells and IgE were required for induction of antibody and Th2-cell-mediated responses to peanut ingestion and they impaired regulatory T (Treg) cell induction. Mast-cell-targeted genetic deletion of the FcεRI signaling kinase Syk or Syk blockade also prevented peanut sensitization. In mice with established allergy, Syk blockade facilitated desensitization and induction of Treg cells, which suppressed allergy when transferred to naive recipients. Our study suggests a key role for IgE in driving Th2 cell and IgE responses while suppressing Treg cells in food allergy. PMID:25017467

  9. Propyl gallate inhibits adipogenesis by stimulating extracellular signal-related kinases in human adipose tissue-derived mesenchymal stem cells.

    Science.gov (United States)

    Lee, Jeung-Eun; Kim, Jung-Min; Jang, Hyun-Jun; Lim, Se-Young; Choi, Seon-Jeong; Lee, Nan-Hee; Suh, Pann-Ghill; Choi, Ung-Kyu

    2015-04-01

    Propyl gallate (PG) used as an additive in various foods has antioxidant and anti-inflammatory effects. Although the functional roles of PG in various cell types are well characterized, it is unknown whether PG has effect on stem cell differentiation. In this study, we demonstrated that PG could inhibit adipogenic differentiation in human adipose tissue-derived mesenchymal stem cells (hAMSCs) by decreasing the accumulation of intracellular lipid droplets. In addition, PG significantly reduced the expression of adipocyte-specific markers including peroxisome proliferator-activated receptor-γ (PPAR-γ), CCAAT enhancer binding protein-α (C/EBP-α), lipoprotein lipase (LPL), and adipocyte fatty acid-binding protein 2 (aP2). PG inhibited adipogenesis in hAMSCs through extracellular regulated kinase (ERK) pathway. Decreased adipogenesis following PG treatment was recovered in response to ERK blocking. Taken together, these results suggest a novel effect of PG on adipocyte differentiation in hAMSCs, supporting a negative role of ERK1/2 pathway in adipogenic differentiation.

  10. Enhanced differentiation of human embryonic stem cells to mesenchymal progenitors by inhibition of TGF-beta/Activin/Nodal signaling using SB-431542

    DEFF Research Database (Denmark)

    Mahmood, Amer; Harkness, Linda; Schrøder, Henrik Daa;

    2010-01-01

    Directing differentiation of human embryonic stem cells (hESC) into specific cell types using an easy and reproducible protocol is a prerequisite for the clinical use of hESC in regenerative medicine procedures. Here, we report a protocol for directing the differentiation of hESC into mesenchymal...... in vivo. Interestingly, SB-OG cells cultured in 10% fetal bovine serum (FBS) developed into a homogeneous population of mesenchymal progenitors that expressed CD markers characteristic of mesenchymal stem cells (MSC): CD44(+) (100%), CD73(+) (98%), CD146(+) (96%) and CD166(+) (88%) with the ability...... progenitor cells. We demonstrate that inhibition of TGF-beta/Activin/Nodal signaling during embryoid bodies (EB) formation using SB-431542 (SB) in serum free medium, markedly up-regulated paraxial mesodermal markers (TBX6, TBX5), and several myogenic developmental markers including early myogenic...

  11. Cell signaling review series

    Institute of Scientific and Technical Information of China (English)

    Aiming Lin; Zhenggang Liu

    2008-01-01

    @@ Signal transduction is pivotal for many, if not all, fundamental cellular functions including proliferation, differentiation, transformation and programmed cell death. Deregulation of cell signaling may result in certain types of cancers and other human diseases.

  12. Aberrant Activation of Notch Signaling Inhibits PROX1 Activity to Enhance the Malignant Behavior of Thyroid Cancer Cells.

    Science.gov (United States)

    Choi, Dongwon; Ramu, Swapnika; Park, Eunkyung; Jung, Eunson; Yang, Sara; Jung, Wonhyeuk; Choi, Inho; Lee, Sunju; Kim, Kyu Eui; Seong, Young Jin; Hong, Mingu; Daghlian, George; Kim, Daniel; Shin, Eugene; Seo, Jung In; Khatchadourian, Vicken; Zou, Mengchen; Li, Wei; De Filippo, Roger; Kokorowski, Paul; Chang, Andy; Kim, Steve; Bertoni, Ana; Furlanetto, Tania Weber; Shin, Sung; Li, Meng; Chen, Yibu; Wong, Alex; Koh, Chester; Geliebter, Jan; Hong, Young-Kwon

    2016-02-01

    Papillary thyroid cancer (PTC) is one of the most common endocrine malignancies associated with significant morbidity and mortality. Although multiple studies have contributed to a better understanding of the genetic alterations underlying this frequently arising disease, the downstream molecular effectors that impact PTC pathogenesis remain to be further defined. Here, we report that the regulator of cell fate specification, PROX1, becomes inactivated in PTC through mRNA downregulation and cytoplasmic mislocalization. Expression studies in clinical specimens revealed that aberrantly activated NOTCH signaling promoted PROX1 downregulation and that cytoplasmic mislocalization significantly altered PROX1 protein stability. Importantly, restoration of PROX1 activity in thyroid carcinoma cells revealed that PROX1 not only enhanced Wnt/β-catenin signaling but also regulated several genes known to be associated with PTC, including thyroid cancer protein (TC)-1, SERPINA1, and FABP4. Furthermore, PROX1 reexpression suppressed the malignant phenotypes of thyroid carcinoma cells, such as proliferation, motility, adhesion, invasion, anchorage-independent growth, and polyploidy. Moreover, animal xenograft studies demonstrated that restoration of PROX1 severely impeded tumor formation and suppressed the invasiveness and the nuclear/cytoplasmic ratio of PTC cells. Taken together, our findings demonstrate that NOTCH-induced PROX1 inactivation significantly promotes the malignant behavior of thyroid carcinoma and suggest that PROX1 reactivation may represent a potential therapeutic strategy to attenuate disease progression. PMID:26609053

  13. The Effects of Inhibiting Hedgehog Signaling Pathways by Using Specific Antagonist Cyclopamine on the Chondrogenic Differentiation of Mesenchymal Stem Cells

    Directory of Open Access Journals (Sweden)

    Zheng-Rong Chen

    2013-03-01

    Full Text Available This study aimed to investigate the effects of cyclopamine, a specific inhibitor of Hedgehog signaling pathways, on the chondrogenic differentiation of mesenchymal stem cells (MSCs. During culture, the experimental groups were treated with cyclopamine and their cell proliferation status was assessed using the MTT test. The extra-bone cellular matrix (ECM and Collagen II (Col II was detected by toluidine blue staining and immunohistochemistry of cells. The concentrations of Col II and aggrecan in the culture solution and cytosol were detected using ELISA on the 7th, 14th, and 21st days of cyclopamine induction. Gene and protein expression of Col II and aggrecan were analyzed on the 14th day of cyclopamine induction using real-time PCR and western blot analyses. No significant differences in proliferation of mesenchymal stem cells were found between the control group and the group treated with cyclopamine. Compared to the blank control group, the ECM level was low and the protein and mRNA concentrations of Collagen II (Col II and aggrecan in the culture solution and cytosol, respectively, were significantly reduced in the experimental group. The Smo acted as a key point in the regulations of Hedgehog signaling pathway on the chondrogenic differentiation of rabbit MSCs.

  14. Matrine inhibits the proliferation, invasion and migration of castration-resistant prostate cancer cells through regulation of the NF-κB signaling pathway.

    Science.gov (United States)

    Li, Qi; Lai, Yiming; Wang, Chengbin; Xu, Guibin; He, Zheng; Shang, Xiaohong; Sun, Yi; Zhang, Fan; Liu, Leyuan; Huang, Hai

    2016-01-01

    Matrine is a naturally occurring alkaloid extracted from the Chinese herb Sophora flavescens. It has been demonstrated to exhibit antiproliferative properties, promote apoptosis and inhibit cell invasion in a number of cancer cell lines. It has also been shown to improve the efficacy of chemotherapy when it is combined with other chemotherapy drugs. However, the therapeutic efficacy of matrine for prostate cancer remains poorly understood. In the present study, we showed that matrine inhibited the proliferation, migration and invasion of both DU145 and PC-3 cells in a dose- and time-dependent manner. It also reduced the cell population at S phase and increased the cell population at sub-G1 phase. The increases in both the apoptotic cell population and cell population at S and sub-G1 phases consistently indicated a pro-apoptotic effect of matrine. Decreases in levels of P65, p-P65, IKKα/β, p-IKKα/β, IKBα and p-IKBα as detected by immunoblot analysis in the matrine-treated DU145 and PC-3 cells suggested an involvement of the NF-κB signaling pathway. Therefore, it is a novel promising addition to the current arsenal of chemotherapy drugs for the treatment of androgen-independent prostate cancer.

  15. Matrine inhibits the proliferation, invasion and migration of castration-resistant prostate cancer cells through regulation of the NF-κB signaling pathway.

    Science.gov (United States)

    Li, Qi; Lai, Yiming; Wang, Chengbin; Xu, Guibin; He, Zheng; Shang, Xiaohong; Sun, Yi; Zhang, Fan; Liu, Leyuan; Huang, Hai

    2016-01-01

    Matrine is a naturally occurring alkaloid extracted from the Chinese herb Sophora flavescens. It has been demonstrated to exhibit antiproliferative properties, promote apoptosis and inhibit cell invasion in a number of cancer cell lines. It has also been shown to improve the efficacy of chemotherapy when it is combined with other chemotherapy drugs. However, the therapeutic efficacy of matrine for prostate cancer remains poorly understood. In the present study, we showed that matrine inhibited the proliferation, migration and invasion of both DU145 and PC-3 cells in a dose- and time-dependent manner. It also reduced the cell population at S phase and increased the cell population at sub-G1 phase. The increases in both the apoptotic cell population and cell population at S and sub-G1 phases consistently indicated a pro-apoptotic effect of matrine. Decreases in levels of P65, p-P65, IKKα/β, p-IKKα/β, IKBα and p-IKBα as detected by immunoblot analysis in the matrine-treated DU145 and PC-3 cells suggested an involvement of the NF-κB signaling pathway. Therefore, it is a novel promising addition to the current arsenal of chemotherapy drugs for the treatment of androgen-independent prostate cancer. PMID:26497618

  16. Coenzyme Q10 Inhibits the Aging of Mesenchymal Stem Cells Induced by D-Galactose through Akt/mTOR Signaling

    Directory of Open Access Journals (Sweden)

    Dayong Zhang

    2015-01-01

    Full Text Available Increasing evidences indicate that reactive oxygen species are the main factor promoting stem cell aging. Recent studies have demonstrated that coenzyme Q10 (CoQ10 plays a positive role in organ and cellular aging. However, the potential for CoQ10 to protect stem cell aging has not been fully evaluated, and the mechanisms of cell senescence inhibited by CoQ10 are still poorly understood. Our previous study had indicated that D-galactose (D-gal can remarkably induce mesenchymal stem cell (MSC aging through promoting intracellular ROS generation. In this study, we showed that CoQ10 could significantly inhibit MSC aging induced by D-gal. Moreover, in the CoQ10 group, the expression of p-Akt and p-mTOR was clearly reduced compared with that in the D-gal group. However, after Akt activating by CA-Akt plasmid, the senescence-cell number in the CoQ10 group was significantly higher than that in the control group. These results indicated that CoQ10 could inhibit D-gal-induced MSC aging through the Akt/mTOR signaling.

  17. Resveratrol inhibits enterovirus 71 replication and pro-inflammatory cytokine secretion in rhabdosarcoma cells through blocking IKKs/NF-κB signaling pathway.

    Directory of Open Access Journals (Sweden)

    Li Zhang

    Full Text Available Polydatin and resveratrol, as major active components in Polygonum cuspidatum, have anti-inflammatory, antioxidant and antitumor functions. However, the effect and mechanism of polydatin and resveratrol on enterovirus 71 (EV71 have not been reported. In this study, resveratrol revealed strong antiviral activity on EV71, while polydatin had weak effect. Neither polydatin nor resveratrol exhibited influence on viral attachment. Resveratrol could effectively inhibit the synthesis of EV71/VP1 and the phosphorylation of IKKα, IKKβ, IKKγ, IKBα, NF-κB p50 and NF-κB p65, respectively. Meanwhile, the remarkably increased secretion of IL-6 and TNF-α in EV71-infected rhabdosarcoma (RD cells could be blocked by resveratrol. These results demonstrated that resveratrol inhibited EV71 replication and cytokine secretion in EV71-infected RD cells through blocking IKKs/NF-κB signaling pathway. Thus, resveratrol may have potent antiviral effect on EV71 infection.

  18. Notch1 signaling inhibits growth of EC109 esophageal carcinoma cells through downmodulation of HPV18 E6/E7 gene expression

    Institute of Scientific and Technical Information of China (English)

    Kejie ZHANG; Quanyi LU; Xiaoqing NIU; Peng ZHANG; Jiangning ZHAO; Zhao WANG; Jiasheng HU; Pu LI; Wenli LIU

    2009-01-01

    Aim:To investigate the role of the Notch1 signaling pathway in growth arrest of an esophageal carcinoma cell line (EC109)in vitro and the mechanism involved.Methods: An intracellular domain of Notch1 (ICN) was transfected into cultured EC109 cells by lipofectamine transfection.Subsequently,the proliferation of the transfected cells was measured by an MTF assay.Cell cycle distribution was ana-lyzed by flow cytometry.Human papillomavirus type 18 (HPV18) E6/E7 mRNA expression was detected by RT-PCR,and p53 protein expression was detected by Western blot.Results: Activation of Notch1 signaling resulted in inhibition of EC109 cell proliferation with the induction of G2/M arrest,downmodulation of HPV18 E6/E7 gene expression,and upregulation of p53 expression.Conclusion: Repression of HPV18 E6/E7 expression by Notch1 signaling results in the activation of p53-mediated pathways with concomitant growth suppression of HPV18-positive EC109 cells.

  19. Curcumin inhibits cellular cholesterol accumulation by regulating SREBP-1/caveolin-1 signaling pathway in vascular smooth muscle cells

    Institute of Scientific and Technical Information of China (English)

    Hao-yu YUAN; Shuang-yu KUANG; Xing ZHENG; Hong-yan LING; Yun-bo YANG; Peng-ke YAN; Kai LI; Duan-fang LIAO

    2008-01-01

    Aim: To investigate the protective effect and the possible mechanism of curcumin on anti-atherosclerosis. Methods: Morphological changes of atherosclerotic le-sions taken from apoE knockout (apoE-/-) mice were determined by hematoxylin-eosin staining. Intracellular lipid droplets and lipid levels were assayed by oil red O staining and HPLC. The protein expression of caveolin-1 was quantified by West-ern blotting. Translocation and the expression of sterol response element-bind-ing protein-1 (SREBP-1) were indirectly detected by an immunofluorescence analysis. Results: The administration of 20 mg.kg-1.d-1 curcumin to apoE-/1 mice for 4 months induced a 50% reduction of atherosclerotic lesions and yielded a 5-fold increase in the caveolin-1 expression level as compared to the model group. Rat vascular smooth muscle cells (VSMC) pretreated with 50 mg.L-1 ox-lipid den-sity lipoprotein(ox-LDL) for 48 h increased cellular lipid contents, and stimulated SREBP-1 translocation, but decreased the caveolin-1 expression level. Lipid-loaded cells exposed to curcumin at various concentrations (12.5, 25, and 50 μmol.L-1) for different durations (0, 6, 12, 24, and 48 h) significantly diminished the number and area of cellular lipid droplets, total cholesterol, cholesterol ester, and free choles-terol accompanying the elevation of the caveolin-1 expression level (approximately 3-fold); the translocation of SREBP-1 from the cytoplasm to the nucleus was inhibited compared with the models. Lipid-loaded VSMC exposed to N-acetyl-Leu-Leu-norleucinal, a SREBP-1 protease inhibitor, showed increased nuclear trans-location of SREBP-1, reduced caveolin-1 expression level, and upregulated cellu-lar lipid levels. Conclusion: Curcumin inhibits ox-LDL-induced cholesterol accu-mulation in cultured VSMC through increasing the caveolin-1 expression via the inhibition of nuclear translocation of SREBP-1.

  20. Odontogenic ameloblast-associated protein (ODAM) inhibits growth and migration of human melanoma cells and elicits PTEN elevation and inactivation of PI3K/AKT signaling

    International Nuclear Information System (INIS)

    The Odontogenic Ameloblast-associated Protein (ODAM) is expressed in a wide range of normal epithelial, and neoplastic tissues, and we have posited that ODAM serves as a novel prognostic biomarker for breast cancer and melanoma. Transfection of ODAM into breast cancer cells yields suppression of cellular growth, motility, and in vivo tumorigenicity. Herein we have extended these studies to the effects of ODAM on cultured melanoma cell lines. The A375 and C8161 melanoma cell lines were stably transfected with ODAM and assayed for properties associated with tumorigenicity including cell growth, motility, and extracellular matrix adhesion. In addition, ODAM–transfected cells were assayed for signal transduction via AKT which promotes cell proliferation and survival in many neoplasms. ODAM expression in A375 and C8161 cells strongly inhibited cell growth and motility in vitro, increased cell adhesion to extracellular matrix, and yielded significant cytoskeletal/morphologic rearrangement. Furthermore, AKT activity was downregulated by ODAM expression while an increase was noted in expression of the PTEN (phosphatase and tensin homolog on chromosome 10) tumor suppressor gene, an antagonist of AKT activation. Increased PTEN in ODAM-expressing cells was associated with increases in PTEN mRNA levels and de novo protein synthesis. Silencing of PTEN expression yielded recovery of AKT activity in ODAM-expressing melanoma cells. Similar PTEN elevation and inhibition of AKT by ODAM was observed in MDA-MB-231 breast cancer cells while ODAM expression had no effect in PTEN-deficient BT-549 breast cancer cells. The apparent anti-neoplastic effects of ODAM in cultured melanoma and breast cancer cells are associated with increased PTEN expression, and suppression of AKT activity. This association should serve to clarify the clinical import of ODAM expression and any role it may serve as an indicator of tumor behavior

  1. Inhibition of TGF-β signaling enables human corneal endothelial cell expansion in vitro for use in regenerative medicine.

    Directory of Open Access Journals (Sweden)

    Naoki Okumura

    Full Text Available Corneal endothelial dysfunctions occurring in patients with Fuchs' endothelial corneal dystrophy, pseudoexfoliation syndrome, corneal endotheliitis, and surgically induced corneal endothelial damage cause blindness due to the loss of endothelial function that maintains corneal transparency. Transplantation of cultivated corneal endothelial cells (CECs has been researched to repair endothelial dysfunction in animal models, though the in vitro expansion of human CECs (HCECs is a pivotal practical issue. In this study we established an optimum condition for the cultivation of HCECs. When exposed to culture conditions, both primate and human CECs showed two distinct phenotypes: contact-inhibited polygonal monolayer and fibroblastic phenotypes. The use of SB431542, a selective inhibitor of the transforming growth factor-beta (TGF-β receptor, counteracted the fibroblastic phenotypes to the normal contact-inhibited monolayer, and these polygonal cells maintained endothelial physiological functions. Expression of ZO-1 and Na(+/K(+-ATPase maintained their subcellular localization at the plasma membrane. Furthermore, expression of type I collagen and fibronectin was greatly reduced. This present study may prove to be the substantial protocol to provide the efficient in vitro expansion of HCECs with an inhibitor to the TGF-β receptor, and may ultimately provide clinicians with a new therapeutic modality in regenerative medicine for the treatment of corneal endothelial dysfunctions.

  2. MicroRNA-33b inhibits lung adenocarcinoma cell growth, invasion, and epithelial-mesenchymal transition by suppressing Wnt/β-catenin/ZEB1 signaling.

    Science.gov (United States)

    Qu, Jingjing; Li, Min; An, Jian; Zhao, Bingrong; Zhong, Wen; Gu, Qihua; Cao, Liming; Yang, Huaping; Hu, Chengping

    2015-12-01

    Altered expression of microRNA (miRNA) is associated with lung carcinogenesis and metastasis. Our previous study of lung cancer miRNAs using the gene chip assay demonstrated altered miR-33b expression in lung adenocarcinoma. The present study further investigated miR-33b expression, function, and gene regulation in lung cancer cells in vitro and in nude mouse xenografts. Our data showed that the level of miR-33b expression was dramatically decreased in lung adenocarcinoma cell lines and tissues and that the reduced miR-33b expression was associated with tumor lymph node metastasis. Furthermore, restoration of miR-33b expression inhibited lung adenocarcinoma cell proliferation, migration, and invasion and tumor cell epithelial-mesenchymal transition (EMT) in vitro. Luciferase assay revealed that miR-33b bound to ZEB1 3'-UTR region and inhibited ZEB1 expression, while expression of ZEB1 mRNA and miR-33b was inversely associated with lung adenocarcinoma cell lines and tissues. Subsequently, we found that miR-33b suppressed the activity of WNT/β-catenin signaling in lung adenocarcinoma cells and in turn suppressed tumor cell growth and EMT in vitro and in vivo nude mouse xenografts. In conclusion, the present study provided novel insight into the molecular mechanism of lung adenocarcinoma progression. MicroRNA-33b should be further investigated as a potential therapeutic target in human lung adenocarcinoma.

  3. 20(S)-ginsenoside Rh2 inhibits the proliferation and induces the apoptosis of KG-1a cells through the Wnt/β-catenin signaling pathway.

    Science.gov (United States)

    Chen, Yi; Liu, Ze-Hong; Xia, Jing; Li, Xiao-Peng; Li, Ke-Qiong; Xiong, Wei; Li, Jing; Chen, Di-Long

    2016-07-01

    Previous research has shown that total saponins of Panax ginseng (TSPG) and other ginsenoside monomers inhibit the proliferation of leukemia cells. However, the effect has not been compared among them. Cell viability was determined by Cell Counting Kit-8 assay, and ultra-structural characteristics were observed under transmission electron microscopy. Cell cycle distribution and apoptosis were determined by flow cytometry (FCM). Real-time fluorescence quantitative‑PCR, western blotting and immunofluorescence were used to measure the expression of β-catenin, TCF4, cyclin D1 and NF-κBp65. β-catenin/TCF4 target gene transcription were observed by ChIP-PCR assay. We found that 20(S)-ginsenoside Rh2 [(S)Rh2] inhibited the proliferation of KG-1a cells more efficiently than the other monomers. Moreover, (S)Rh2 arrested KG-1a cells in the G0/G1 phase and induced apoptosis. In addition, the levels of β-catenin, TCF4, cyclin D1 mRNA and protein were decreased. The ChIP-PCR showed that (S)Rh2 downregulated the transcription of β-catenin/TCF4 target genes, such as cyclin D1 and c-myc. These results indicated that (S)Rh2 induced cell cycle arrest and apoptosis through the Wnt/β-catenin signaling pathway, demonstrating its potential as a chemotherapeutic agent for leukemia therapy. PMID:27121661

  4. Naringin inhibits the invasion and migration of human glioblastoma cell via downregulation of MMP-2 and MMP-9 expression and inactivation of p38 signaling pathway.

    Science.gov (United States)

    Aroui, Sonia; Najlaoui, Feten; Chtourou, Yassine; Meunier, Annie-Claire; Laajimi, Amel; Kenani, Abderraouf; Fetoui, Hamadi

    2016-03-01

    Gliomas are the most common and malignant primary brain tumors. They are associated with a poor prognosis despite the availability of multiple therapeutic options. Naringin, a common dietary flavonoid abundantly present in fruits and vegetables, is believed to possess strong anti-proliferative and anti-cancer properties. However, there are no reports describing its effects on the invasion and migration of glioblastoma cell lines. Our results showed that the treatment of U251 glioma cell lines with different concentrations of naringin inhibited the invasion and migration of these cells. In addition, we revealed a decrease in the levels of matrix metalloproteinases (MMP-2) and (MMP-9) expression as well as proteinase activity in U251 glioma cells. In contrast, the expression of tissue inhibitor of metalloproteinases (TIMP-1) and (TIMP-2) was increased. Furthermore, naringin treatment decreased significantly the phosphorylated level of p38. Combined treatment with a p38 inhibitor (SB203580) resulted in the synergistic reduction of MMP-2 and MMP-9 expressions correlated with an increase of TIMP-1 and TIMP-2 expressions and the anti-invasive properties. However, p38 chemical activator (anisomycin) could block these effects produced by naringin, suggesting a direct downregulation of the p38 signaling pathway. These data suggest that naringin may have therapeutic potential for controlling invasiveness of malignant gliomas by inhibiting of p38 signal transduction pathways. PMID:26474590

  5. Cinnamaldehyde affects the biological behavior of human colorectal cancer cells and induces apoptosis via inhibition of the PI3K/Akt signaling pathway.

    Science.gov (United States)

    Li, Jiepin; Teng, Yuhao; Liu, Shenlin; Wang, Zifan; Chen, Yan; Zhang, Yingying; Xi, Songyang; Xu, Song; Wang, Ruiping; Zou, Xi

    2016-03-01

    Cinnamaldehyde (CA) is a bioactive compound isolated from the stem bark of Cinnamomum cassia, that has been identified as an antiproliferative substance with pro-apoptotic effects on various cancer cell lines in vitro. In the present study, the effects of CA on human colon cancer cells were investigated at both the molecular and cellular levels. Three types of colorectal cancer cells at various stages of differentiation and invasive ability (SW480, HCT116 and LoVo) were treated with CA at final concentrations of 20, 40 and 80 µg/ml for 24 h. Compared with the control group, the proliferation inhibition rate of the human colorectal cancer cells following treatment with CA increased in a dose- and time-dependent manner. The invasion and adhesion abilities of the cells were significantly inhibited as indicated by Transwell and cell-matrix adhesion assays. Meanwhile, CA also upregulated the expression of E-cadherin and downregulated the expression of matrix metalloproteinase-2 (MMP-2) and MMP-9. CA also elevated the apoptotic rate. The levels of pro-apoptotic genes were upregulated while the levels of apoptosis inhibitory genes were decreased which further confirmed the pro-apoptotic effect of CA. In order to explore the mechanism of CA-induced apoptosis, insulin-like growth factor-1 (IGF-1) and PI3K inhibitor (LY294002) were used to regulate the phosphoinositide 3-kinase (PI3K)/AKT pathway. The transcription activity of PI3K/AKT was markedly inhibited by CA, as well as IGF-1 which functions as an anti-apoptotic factor. In conclusion, CA has the potential to be developed as a new antitumor drug. The mechanisms of action involve the regulation of expression of genes involved in apoptosis, invasion and adhesion via inhibition of the PI3K/Akt signaling pathway. PMID:26677144

  6. A novel quinoline, MT477: suppresses cell signaling through Ras molecular pathway, inhibits PKC activity, and demonstrates in vivo anti-tumor activity against human carcinoma cell lines.

    Science.gov (United States)

    Jasinski, Piotr; Welsh, Brandon; Galvez, Jorge; Land, David; Zwolak, Pawel; Ghandi, Lori; Terai, Kaoru; Dudek, Arkadiusz Z

    2008-06-01

    MT477 is a novel thiopyrano[2,3-c]quinoline that has been identified using molecular topology screening as a potential anticancer drug with a high activity against protein kinase C (PKC) isoforms. The objective of the present study was to determine the mechanism of action of MT477 and its activity against human cancer cell lines. MT477 interfered with PKC activity as well as phosphorylation of Ras and ERK1/2 in H226 human lung carcinoma cells. It also induced poly-caspase-dependent apoptosis. MT477 had a dose-dependent (0.006 to 0.2 mM) inhibitory effect on cellular proliferation of H226, MCF-7, U87, LNCaP, A431 and A549 cancer cell lines as determined by in vitro proliferation assays. Two murine xenograft models of human A431 and H226 lung carcinoma were used to evaluate tumor response to intraperitoneal administration of MT477 (33 microg/kg, 100 microg/kg, and 1 mg/kg). Tumor growth was inhibited by 24.5% in A431 and 43.67% in H226 xenografts following MT477 treatment, compared to vehicle controls (p < 0.05). In conclusion, our empirical findings are consistent with molecular modeling of MT477's activity against PKC. We also found, however, that its mechanism of action occurs through suppressing Ras signaling, indicating that its effects on apoptosis and tumor growth in vivo may be mediated by Ras as well as PKC. We propose, therefore, that MT477 warrants further development as an anticancer drug. PMID:17957339

  7. Inhibition of STAT3 signaling and induction of SHP1 mediate antiangiogenic and antitumor activities of ergosterol peroxide in U266 multiple myeloma cells

    International Nuclear Information System (INIS)

    Ergosterol peroxide (EP) derived from edible mushroom has been shown to exert anti-tumor activity in several cancer cells. In the present study, anti-angiogenic activity of EP was investigated with the underlying molecular mechanisms in human multiple myeloma U266 cells. Despite weak cytotoxicity against U266 cells, EP suppressed phosphorylation, DNA binding activity and nuclear translocalization of signal transducer and activator of transcription 3 (STAT3) in U266 cells at nontoxic concentrations. Also, EP inhibited phosphorylation of the upstream kinases Janus kinase 2 (JAK2) and Src in a time-dependent manner. Furthermore, EP increased the expression of protein tyrosine phosphatase SHP-1 at protein and mRNA levels, and conversely silencing of the SHP-1 gene clearly blocked EP-mediated STAT3 inactivation. In addition, EP significantly decreased vascular endothelial growth factor (VEGF), one of STAT3 target genes at cellular and protein levels as well as disrupted in vitro tube formation assay. Moreover, EP significantly suppressed the growth of U266 cells inoculated in female BALB/c athymic nude mice and immunohistochemistry revealed that EP effectively reduced the expression of STAT3 and CD34 in tumor sections compared to untreated control. These findings suggest that EP can exert antitumor activity in multiple myeloma U266 cells partly with antiangiogenic activity targeting JAK2/STAT3 signaling pathway as a potent cancer preventive agent for treatment of multiple myeloma cells

  8. A selective estrogen receptor modulator inhibits TNF-alpha-induced apoptosis by activating ERK1/2 signaling pathway in vascular endothelial cells.

    Science.gov (United States)

    Yu, Jing; Eto, Masato; Akishita, Masahiro; Okabe, Tetsuro; Ouchi, Yasuyoshi

    2009-07-01

    Tumor necrosis factor (TNF-alpha) is a pleiotropic cytokine exerting both inflammatory and cell death activity and is thought to play a role in the pathogenesis of atherosclerosis. The present study was designed to examine whether the raloxifene analogue, LY117018 could inhibit TNF-alpha-induced apoptosis in vascular endothelial cells and to clarify the involved mechanisms. Apoptosis of endothelial cells was determined by DNA fragmentation assay and the activation of caspase-3. LY117018 significantly inhibited TNF-alpha-induced caspase-3 activation and cell DNA fragmentation levels in bovine carotid artery endothelial cells. The inhibitory effect of LY117018 was abolished by an estrogen receptor antagonist ICI 182,780. p38 MAPK, JNK, ERK1/2 and Akt have been shown to act as apoptotic or anti-apoptotic signals. TNF-alpha stimulated the phosphorylation levels of p38 MAPK, JNK, ERK1/2 and Akt in vascular endothelial cells. TNF-alpha-induced apoptosis was significantly decreased by SB203580, a p38 MAPK inhibitor or SP600125, a JNK inhibitor, but was enhanced by an ERK1/2 pathway inhibitor, PD98059 or a PI3-kinase/Akt pathway inhibitor, wortmannin. The anti-apoptotic effect of LY117018 was abrogated only by PD98059 but was not affected by the inhibitors for p38 MAPK, JNK, or Akt. LY117018 stimulated the further increase in phosphorylation of ERK1/2 in TNF-alpha treated endothelial cells but it did not affect phosphorylation levels of p38 MAPK, JNK or Akt. These results suggest that LY 110718 prevents caspase-3 dependent apoptosis induced by TNF-alpha in vascular endothelial cells through activation of the estrogen receptors and the ERK1/2 signaling pathway. PMID:19275968

  9. Suppressive Effects of Plumbagin on Invasion and Migration of Breast Cancer Cells via the Inhibition of STAT3 Signaling and Down-regulation of Inflammatory Cytokine Expressions

    Institute of Scientific and Technical Information of China (English)

    Wei Yan; Bing Tu; Yun-yun Liu; Ting-yu Wang; Han Qiao; Zan-jing Zhai; Hao-wei Li; Ting-ting Tang

    2013-01-01

    Objective:The aim of this study was to investigate the effects of plumbagin (PL), a naphthoquinone derived from the medicinal plant plumbago zeylanica, on the invasion and migration of human breast cancer cells. Methods:Human breast cancer MDA-MB-231SArfp cells were treated with different concentrations of plum-bagin for 24 h. The effects of plumbagin on the migration and invasion were observed by a transwell method. The expressions of IL-1α, IL-1β, IL-6, IL-8, TGF-β, TNFα, MMP-2 and MMP-9 mRNA in M DA-MB-231SArfp cells were detected using Real-Time PCR. MDA-MB-231SArfp cells were treated with plumbagin at different concentrations for 45 minutes. The activation of STAT3 was detected by western blot. Following this analysis, STAT3 in MDA-MB-231SArfp cells was knocked out using specific siRNA. mRNA levels of IL-1α, TGF-β, MMP-2 and MMP-9 were then detected. Consequently, MDA-MB-231SArfp cells were injected intracardially into BALB/c nude mice to construct a breast cancer bone metastatic model. The mice were injected intra-peritoneally with plumbagin. Non-invasive in vivo monitoring, X-ray imaging and histological staining were performed to investigate the effects of plumbagin on the invasion and migration of breast cancer cells in vivo. Results: The in vitro results showed that plumbagin could suppress the migration and invasion of breast cancer cells and down-regulate mRNA expressions of IL-1α, TGF-β, MMP-2 and MMP-9. Western blotting demonstrated that plumbagin inhibited the activation of STAT3 signaling in MDA-MB-231SArfp cells. The inactivation of STAT3 was found to have an inhibitory effect on the expressions of IL-1α, TGF-β, MMP-2 and MMP-9. In vivo studies showed that plumbagin inhibited the metastasis of breast cancer cells and decreased osteolytic bone metastases, as well as the secretion of MMP-2 and MMP-9 by tumor cells at metastatic lesions. Conclusions:Plumbagin can suppress the invasion and migration of breast cancer cells via the inhibition

  10. RSK2-induced stress tolerance enhances cell survival signals mediated by inhibition of GSK3β activity

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Cheol-Jung; Lee, Mee-Hyun; Lee, Ji-Young; Song, Ji Hong; Lee, Hye Suk; Cho, Yong-Yeon, E-mail: yongyeon@catholic.ac.kr

    2013-10-11

    Highlights: •We demonstrated a novel function of RSK2 in stress tolerance. •RSK2 deficiency enhanced apoptosis by calcium stress. •RSK2-mediated GSK3β phosphorylation at serine 9 increased calcium-induced stress tolerance. •Calcium stress-induced apoptosis inhibited by adding back of RSK2 into RSK2{sup −/−} MEFs. -- Abstract: Our previous studies demonstrated that RSK2 plays a key role in cell proliferation and transformation induced by tumor promoters such as epidermal growth factor (EGF) in mouse and human skin cells. However, no direct evidence has been found regarding the relationship of RSK2 and cell survival. In this study, we found that RSK2 interacted and phosphorylated GSK3β at Ser9. Notably, GSK3β phosphorylation at Ser9 was suppressed in RSK2{sup −/−} MEFs compared with RSK2{sup +/+} MEFs by stimulation of EGF and calcium ionophore A23187, a cellular calcium stressor. In proliferation, we found that RSK2 deficiency suppressed cell proliferation compared with RSK2{sup +/+} MEFs. In contrast, GSK3β{sup −/−} MEFs induced the cell proliferation compared with GSK3β{sup +/+} MEFs. Importantly, RSK2{sup −/−} MEFs were induced severe cellular morphology change by A23187 and enhanced G1/G0 and sub-G1 accumulation of the cell cycle phase compared with RSK2{sup +/+} MEFs. The sub-G1 induction in RSK2{sup −/−} MEFs by A23187 was correlated with increase of cytochrome c release, caspase-3 cleavage and apoptotic DNA fragmentation compared with RSK2{sup +/+} MEFs. Notably, return back of RSK2 into RSK2{sup −/−} MEFs restored A23187-induced morphological change, and decreased apoptosis, apoptotic DNA fragmentation and caspase-3 induction compared with RSK2{sup −/−}/mock MEFs. Taken together, our results demonstrated that RSK2 plays an important role in stress-tolerance and cell survival, resulting in cell proliferation and cancer development.

  11. Chikusetsusaponin IVa Butyl Ester (CS-IVa-Be), a Novel IL6R Antagonist, Inhibits IL6/STAT3 Signaling Pathway and Induces Cancer Cell Apoptosis.

    Science.gov (United States)

    Yang, Jie; Qian, Shihui; Cai, Xueting; Lu, Wuguang; Hu, Chunping; Sun, Xiaoyan; Yang, Yang; Yu, Qiang; Gao, S Paul; Cao, Peng

    2016-06-01

    The activation of IL6/STAT3 signaling is associated with the pathogenesis of many cancers. Agents that suppress IL6/STAT3 signaling have cancer-therapeutic potential. In this study, we found that chikusetsusaponin IVa butyl ester (CS-IVa-Be), a triterpenoid saponin extracted from Acanthopanas gracilistylus W.W.Smith, induced cancer cell apoptosis. CS-IVa-Be inhibited constitutive and IL6-induced STAT3 activation, repressed STAT3 DNA-binding activity, STAT3 nuclear translocation, IL6-induced STAT3 luciferase reporter activity, IL6-induced STAT3-regulated antiapoptosis gene expression in MDA-MB-231 cells, and IL6-induced TF-1 cell proliferation. Surprisingly, CS-IVa-Be inhibited IL6 family cytokines rather than other cytokines induced STAT3 activation. Further studies indicated that CS-IVa-Be is an antagonist of IL6 receptor via directly binding to the IL6Rα with a Kd of 663 ± 74 nmol/L and the GP130 (IL6Rβ) with a Kd of 1,660 ± 243 nmol/L, interfering with the binding of IL6 to IL6R (IL6Rα and GP130) in vitro and in cancer cells. The inhibitory effect of CS-IVa-Be on the IL6-IL6Rα-GP130 interaction was relatively specific as CS-IVa-Be showed higher affinity to IL6Rα than to LIFR (Kd: 4,910 ± 1,240 nmol/L) and LeptinR (Kd: 4,990 ± 915 nmol/L). We next demonstrated that CS-IVa-Be not only directly induced cancer cell apoptosis but also sensitized MDA-MB-231 cells to TRAIL-induced apoptosis via upregulating DR5. Our findings suggest that CS-IVa-Be as a novel IL6R antagonist inhibits IL6/STAT3 signaling pathway and sensitizes the MDA-MB-231 cells to TRAIL-induced cell death. Mol Cancer Ther; 15(6); 1190-200. ©2016 AACR.

  12. Engineering cell-cell signaling.

    Science.gov (United States)

    Blagovic, Katarina; Gong, Emily S; Milano, Daniel F; Natividad, Robert J; Asthagiri, Anand R

    2013-10-01

    Juxtacrine cell-cell signaling mediated by the direct interaction of adjoining mammalian cells is arguably the mode of cell communication that is most recalcitrant to engineering. Overcoming this challenge is crucial for progress in biomedical applications, such as tissue engineering, regenerative medicine, immune system engineering and therapeutic design. Here, we describe the significant advances that have been made in developing synthetic platforms (materials and devices) and synthetic cells (cell surface engineering and synthetic gene circuits) to modulate juxtacrine cell-cell signaling. In addition, significant progress has been made in elucidating design rules and strategies to modulate juxtacrine signaling on the basis of quantitative, engineering analysis of the mechanical and regulatory role of juxtacrine signals in the context of other cues and physical constraints in the microenvironment. These advances in engineering juxtacrine signaling lay a strong foundation for an integrative approach to utilize synthetic cells, advanced 'chassis' and predictive modeling to engineer the form and function of living tissues.

  13. Inhibition of signal transducer and activator of transcription 3 expression by RNA interference suppresses invasion through inducing anoikis in human colon cancer cells

    Institute of Scientific and Technical Information of China (English)

    Yu Fan; You-Li Zhang; Ying Wu; Wei Zhang; Yin-Huan Wang; Zhao-Ming Cheng; Hua Li

    2008-01-01

    AIM: To investigate the roles and mechanism of signal transducer and activator of transcription 3 (STAT3) in invasion of human colon cancer cells by RNA interference. METHODS: Small interfering RNA (siRNA) targeting Signal transducer and activator of transcription 3 (STAT3) was transfected into HT29 colon cancer cells. STAT3 protein level and DNA-binding activity of STAT3 was evaluated by western blotting and electrophoretic mobility shift assay (EMSA), respectively. We studied the anchorage-independent growth using colony formation in soft agar, and invasion using the boyden chamber model, anoikis using DNA fragmentation assay and terminal deoxynucleotidyltransferase-mediated dUTP nick-end labeling (TUNEL), respectively. Western blot assay was used to observe the protein expression of Bcl-xL and survivin in colon cancer HT29 cells. RESULTS: RNA interference (RNAi) mediated by siRNA leads to suppression of STAT3 expression in colon cancer cell lines. Suppression of STAT3 expression by siRNA could inhibit anchorage-independent growth, and invasion ability, and induces anoikis in the colon cancer cell line HT29. It has been shown that knockdown of STAT3 expression by siRNA results in a reduction in expression of Bcl-xL and survivin in HT29 cells. CONCLUSION: These results suggest that STAT3 siRNA can inhibit the invasion ability of colon cancer cells through inducing anoikis, which antiapoptotic genes survivin and Bcl-xL contribute to regulation of anoikis. These studies indicate STAT3 siRNA could be a useful therapeutic tool for the treatment of colon cancer.

  14. N-acetylcysteine attenuates hexavalent chromium-induced hypersensitivity through inhibition of cell death, ROS-related signaling and cytokine expression.

    Directory of Open Access Journals (Sweden)

    Yu-Hsuan Lee

    Full Text Available Chromium hypersensitivity (chromium-induced allergic contact dermatitis is an important issue in occupational skin disease. Hexavalent chromium (Cr (VI can activate the Akt, Nuclear factor κB (NF-κB, and Mitogen-activated protein kinase (MAPK pathways and induce cell death, via the effects of reactive oxygen species (ROS. Recently, cell death stimuli have been proposed to regulate the release of inflammatory cytokines, such as tumor necrosis factor-α (TNF-α and interleukin-1 (IL-1. However, the exact effects of ROS on the signaling molecules and cytotoxicity involved in Cr(VI-induced hypersensitivity have not yet been fully demonstrated. N-acetylcysteine (NAC could increase glutathione levels in the skin and act as an antioxidant. In this study, we investigated the effects of NAC on attenuating the Cr(VI-triggered ROS signaling in both normal keratinocyte cells (HaCaT cells and a guinea pig (GP model. The results showed the induction of apoptosis, autophagy and ROS were observed after different concentrations of Cr(VI treatment. HaCaT cells pretreated with NAC exhibited a decrease in apoptosis and autophagy, which could affect cell viability. In addition, Cr (VI activated the Akt, NF-κB and MAPK pathways thereby increasing IL-1α and TNF-α production. However, all of these stimulation phenomena could be inhibited by NAC in both of in vitro and in vivo studies. These novel findings indicate that NAC may prevent the development of chromium hypersensitivity by inhibiting of ROS-induced cell death and cytokine expression.

  15. Decorin-mediated inhibition of the migration of U87MG glioma cells involves activation of autophagy and suppression of TGF-β signaling.

    Science.gov (United States)

    Yao, Ting; Zhang, Chen-Guang; Gong, Ming-Tao; Zhang, Min; Wang, Lei; Ding, Wei

    2016-07-01

    Decorin (DCN) is a major member of the small leucine-rich proteoglycan (SLRP) family that is critically involved in tumorigenesis and the development of metastasis of cancers, including glioma. Overexpression of DCN was indicated to suppress glioma cell growth. However, the role of DCN in the migration of glioma cells remain elusive. In this study, we found that treatment with exogenous DCN inhibited the adhesion and migration of U87MG glioma cells with down-regulation of TGF-β signaling. DCN also activated autophagy, as indicated by monodansylcadaverine (MDC) staining, increase in LC3 I/LC3 II conversion, and p62/SQSTM1 degradation in U87MG cells. The increased activity of autophagy was found to be connected to the inhibition on glioma cell migration. Knockdown of DCN expression or the disruption of autophagy with 3-methyladenine (3-MA) was able to reduce the suppression on cell adhesion and migration induced by DCN. When U87MG cells were treated with temozolomide (TMZ), induction of autophagy and up-regulation of DCN were observed, accompanied by suppressed cell adhesion and migration. Transfection of siRNA targeting DCN attenuated the suppressive effect of TMZ on glioma cell migration and adhesion. Our results indicated that the migration of glioma cells was under the control of the active status of autophagy, with DCN serving as a key player, as well as an indicator of the outcome. Therefore, it is suggested that autophagy-modulating reagents could be considered for the treatment of invasive glioma.

  16. Inhibition of Grb2-mediated activation of MAPK signal transduction suppresses NOR1/CB1954-induced cytotoxicity in the HepG2 cell line.

    Science.gov (United States)

    Gui, Rong; Li, Dengqing; Qi, Guannan; Suhad, Ali; Nie, Xinmin

    2012-09-01

    The nitroreductase oxidored-nitro domain containing protein 1 (NOR1) gene may be involved in the chemical carcinogenesis of hepatic cancer and nasopharyngeal carcinoma (NPC). We have previously demonstrated that NOR1 overexpression is capable of converting the monofunctional alkylating agent 5-(aziridin-1-yl)-2,4-dinitrobenzamide (CB1954) into a toxic form by reducing the 4-nitro group of CB1954. Toxic CB1954 is able to enhance cell killing in the NPC cell line CNE1; however, the underlying mechanisms remain unknown. Using cDNA microarrays and quantitative real-time PCR, we previously discovered that NOR1 increases the expression of growth factor receptor-bound protein 2 (Grb2) mRNA by 4.8-fold in the human hepatocellular carcinoma cell line HepG2. In the present study, we revealed that NOR1 increased Grb2 protein expression by 3-fold in HepG2 cells. Additionally, we demonstrated that NOR1 enhanced CB1954-induced cell killing in HepG2 cells, and cell cytotoxicity was inhibited with the tyrosine kinase inhibitor genistein, or by stable transfection of Grb2 small hairpin RNA (shRNA) pU6(+27)-shGrb2 to silence the expression of Grb2. Western blot analysis revealed that Grb2 downregulation may reduce the activity of the mitogen-activated protein kinase (MAPK). Inhibiting the activation of MAPK using the methyl ethyl ketone (MEK) inhibtor PD98059 suppressed CB1954-induced cell killing. These results suggested that the NOR1 gene enhances CB1954-mediated cell cytotoxicity through the upregulation of Grb2 expression and the activation of MAPK signal transduction in the HepG2 cell line. PMID:23741254

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

    Directory of Open Access Journals (Sweden)

    Yanfei Jia

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

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

    Science.gov (United States)

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

    2016-01-01

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

  19. Inhibition of insulin-like growth factor-1 receptor signaling enhances growth-inhibitory and proapoptotic effects of gefitinib (Iressa) in human breast cancer cells

    International Nuclear Information System (INIS)

    Gefitinib (Iressa, ZD 1839, AstraZeneca) blocks the tyrosine kinase activity of the epidermal growth factor receptor (EGFR) and inhibits proliferation of several human cancer cell types including breast cancer. Phase II clinical trials with gefitinib monotherapy showed an objective response of 9 to 19% in non-small-cell lung cancer patients and less than 10% for breast cancer, and phase III results have indicated no benefit of gefitinib in combination with chemotherapy over chemotherapy alone. In order to improve the antineoplastic activity of gefitinib, we investigated the effects of blocking the signalling of the insulin-like growth factor 1 receptor (IGF-1R), a tyrosine kinase with a crucial role in malignancy that is coexpressed with EGFR in most human primary breast carcinomas. AG1024 (an inhibitor of IGF-1R) was used with gefitinib for treatment of MDA468, MDA231, SK-BR-3, and MCF-7 breast cancer lines, which express similar levels of IGF-1R but varying levels of EGFR. Proliferation assays, apoptosis induction studies, and Western blot analyses were conducted with cells treated with AG1024 and gefitinib as single agents and in combination. Gefitinib and AG1024 reduced proliferation in all lines when used as single agents, and when used in combination revealed an additive-to-synergistic effect on cell growth inhibition. Flow cytometry measurements of cells stained with annexin V-propidium iodide and cells stained for caspase-3 activation indicated that adding an IGF-1R-targeting strategy to gefitinib results in higher levels of apoptosis than are achieved with gefitinib alone. Gefitinib either reduced or completely inhibited p42/p44 Erk kinase phosphorylation, depending on the cell line, while Akt phosphorylation was reduced by a combination of the two agents. Overexpression of IGF-1R in SK-BR-3 cells was sufficient to cause a marked enhancement in gefitinib resistance. These results indicate that IGF-1R signaling reduces the antiproliferative effects of

  20. Inhibition of Phosphate-Induced Vascular Smooth Muscle Cell Osteo-/Chondrogenic Signaling and Calcification by Bafilomycin A1 and Methylamine

    Directory of Open Access Journals (Sweden)

    Ioana Alesutan

    2015-09-01

    Full Text Available Background/Aims: Excessive phosphate concentrations trigger vascular calcification, an active process promoted by osteoinduction of vascular smooth muscle cells (VSMCs with increased expression and activity of transcription factor RUNX2 (Core-binding factor α1, CBFA1, alkaline phosphatase (ALPL, TGFß1, transcription factor NFAT5, and NFAT5-sensitive transcription factor SOX9. The osteoinductive signaling and vascular calcification of hyperphosphatemic klotho-hypomorphic mice could be reversed by treatment with NH4Cl, effects involving decrease of TGFß1 and inhibition of NFAT5-dependent osteoinductive signaling. Known effects of NH4Cl include alkalinization of acidic cellular compartments. The present study explored whether osteo-/chondrogenic signaling could be influenced by alkalinization of acidic cellular compartments following inhibition of the vacuolar H+ ATPase with bafilomycin A1 or following dissipation of the pH gradient across the membranes of acidic cellular compartments with methylamine. Methods: Primary human aortic smooth muscle cells (HAoSMCs were treated with high phosphate to trigger osteo-/chondrogenic signaling and calcification in the absence or presence of bafilomycin A1 or methylamine. Calcium content was determined using a QuantiChrom Calcium assay, ALP activity by a colorimetric assay and transcript levels by quantitative RT-PCR. Results: High phosphate increased significantly the calcium deposition, CBFA1 and ALPL mRNA expression as well as alkaline phosphatase activity in HAoSMCs, all effects ameliorated by both, bafilomycin A1 and methylamine. High phosphate further significantly up-regulated the mRNA levels of TGFB1, NFAT5 and SOX9, effects significantly blunted by additional treatment with bafilomycin A1 or methylamine. Treatment of HAoSMCs with human TGFß1 protein or high phosphate up-regulated NFAT5, SOX9, CBFA1 and ALPL mRNA expression to similarly high levels which could not be further increased by combined

  1. Study on Effects of Extracts from Salvia Miltiorrhiza and Curcuma Longa in Inhibiting Phosphorylated Extracellular Signal Regulated Kinase Expression in Rat's Hepatic Stellate Cells

    Institute of Scientific and Technical Information of China (English)

    CHENG Yang; PING Jian; LIU Cheng; TAN Ying-zi; CHEN Gao-feng

    2006-01-01

    Objective: To study the effect of salvianolic acid B (SAB) and curcumin, the extracts of Salvia Miltiorrhiza and Curcuma Longa, on the proliferation and activation of hepatic stellate cell (HSC), and the extracellular signal regulated kinase (ERK) expression in it. Methods: Rat's HSC-T6 were cultured and treated by SAB or curcumin. The inhibitory effect on cell proliferation was determined by 3-(4,5-dimthyl-2-2thiazoly)-2,5-diphenyl-2H-tetrazolium bromide (MTT) colorimetry, and the expression levels of α smooth actin (α-SMA), collagen type Ⅰ , and ERK were determined by Western blot. Results: SAB and curcumin inhibited the proliferation and activation of rat's HSC-T6 in dose-dependent fashion and significantly reduced the expression level of α-SMA ( P<0.01 ). Curcumin significantly reduced the expression of collagen type Ⅰ( P<0.05). Both SAB and curcumin showed insignificant effect on the ERK expression level, but they could significantly reduce the level of phosphorylated-ERK expression, showing significant difference as compared with that in the control group ( P<0.01 and P<0.05 respectively). Conclusion: SAB and curcumin could significantly inhibit the proliferation, activation of HSC, and the production of type Ⅰ collagen in HSC, the mechanism may be associated with their inhibition on ERK phosphorylation.

  2. Ruthenium Polypyridyl Complex Inhibits Growth and Metastasis of Breast Cancer Cells by Suppressing FAK signaling with Enhancement of TRAIL-induced Apoptosis

    Science.gov (United States)

    Cao, Wenqiang; Zheng, Wenjie; Chen, Tianfeng

    2015-03-01

    Ruthenium-based complexes have emerged as promising antitumor and antimetastatic agents during the past decades. However, the limited understanding of the antimetastatic mechanisms of these agents is a roadblock to their clinical application. Herein, we reported that, RuPOP, a ruthenium polypyridyl complex with potent antitumor activity, was able to effectively inhibit growth and metastasis of MDA-MB-231 cells and synergistically enhance TRAIL-induced apoptosis. The selective intracellular uptake and cytotoxic effect of RuPOP was found associated with transferring receptor (TfR)-mediated endocytosis. Further investigation on intracellular mechanisms reveled that RuPOP notably suppressed FAK-mediated ERK and Akt activation. Pretreatment of cells with ERK inhibitor (U0126) and PI3K inhibitor (LY294002) significantly potentiated the inhibitory effect of RuPOP on cell growth, migration and invasion. Moreover, the alternation in the expression levels of metastatic regulatory proteins, including uPA, MMP-2/-9, and inhibition of VEGF secretion were also observed after RuPOP treatment. These results demonstrate the inhibitory effect of RuPOP on the growth and metastasis of cancer cells and the enhancement of TRAIL-induced apoptosis though suppression of FAK-mediated signaling. Furthermore, RuPOP exhibits the potential to be developed as a metal-based antimetastatic agent and chemosensitizer of TRAIL for the treatment of human metastatic cancers.

  3. Testosterone delays vascular smooth muscle cell senescence and inhibits collagen synthesis via the Gas6/Axl signaling pathway.

    Science.gov (United States)

    Chen, Yan-Qing; Zhao, Jing; Jin, Cheng-Wei; Li, Yi-Hui; Tang, Meng-Xiong; Wang, Zhi-Hao; Zhang, Wei; Zhang, Yun; Li, Li; Zhong, Ming

    2016-06-01

    Testosterone deficiency is associated with a higher incidence of cardiovascular diseases in men. However, its effect on cell senescence, which plays a causal role in vascular aging, remains unclear. Here, we tested the hypothesis that testosterone alleviated vascular smooth muscle cell (VSMC) senescence and collagen synthesis via growth arrest-specific protein 6 (Gas6)/Axl- and Akt/FoxO1a-dependent pathways. Testosterone significantly ameliorated angiotensin II-induced VSMC senescence and collagen overexpression. In addition, testosterone inhibited angiotensin II-induced matrix metalloproteinase-2 (MMP-2) activity, which played a pivotal role in facilitating age-related collagen deposition. Testosterone increased the expression of tissue inhibitor of metalloproteinase-2 but decreased the expression of MMP-2 and membrane type-1 metalloproteinase which contributed to increase MMP-2 activity. The effects on VSMCs senescence and collagen synthesis were mediated by restoration of angiotensin II-induced downregulation of Gas6 and Axl expression and a subsequent reduction of Akt and FoxO1a phosphorylation. The effects of testosterone were reversed by a Gas6 blocker, Axl-Fc, and a specific inhibitor of Axl, R428. Treatment of VSMCs with PI3K inhibitor LY294002 abrogated the downregulating effect of testosterone on MMP-2 activity. Furthermore, when FoxO1a expression was silenced by using a specific siRNA, the inhibitory effect of testosterone on MMP-2 activity was revered as well, that indicated this process was Akt/FoxO1a dependence. Taken together, Gas6/Axl and Akt/FoxO1a were involved in protective effects of testosterone on VSMCs senescence and collagen synthesis. Our results provide a novel mechanism underlying the protective effect of testosterone on vascular aging and may serve as a theoretical basis for testosterone replacement therapy. PMID:27206970

  4. Cyp26b1 regulates retinoic acid-dependent signals in T cells and its expression is inhibited by transforming growth factor-β.

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    Hajime Takeuchi

    Full Text Available BACKGROUND: The vitamin A metabolite, retinoic acid (RA, plays important roles in the regulation of lymphocyte properties. Dendritic cells in gut-related lymphoid organs can produce RA, thereby imprinting gut-homing specificity on T cells and enhancing transforming growth factor (TGF-β-dependent induction of Foxp3+ regulatory T cells upon antigen presentation. In general, RA concentrations in cells and tissues are regulated by its degradation as well. However, it remained unclear if T cells could actively catabolize RA. METHODOLOGY/PRINCIPAL FINDINGS: We assessed the expression of known RA-catabolizing enzymes in T cells from mouse lymphoid tissues. Antigen-experienced CD44+ T cells in gut-related lymphoid organs selectively expressed Cyp26b1, a member of the cytochrome P450 family 26. However, T cells in the spleen or skin-draining lymph nodes did not significantly express Cyp26b1. Accordingly, physiological levels of RA (1-10 nM could induce Cyp26b1 expression in naïve T cells upon activation in vitro, but could not do so in the presence of TGF-β. Overexpression of Cyp26b1 significantly suppressed the RA effect to induce expression of the gut-homing receptor CCR9 on T cells. On the other hand, knocking down Cyp26b1 gene expression with small interfering RNA or inhibiting CYP26 enzymatic activity led to enhancement of the RA-induced CCR9 expression. CONCLUSIONS/SIGNIFICANCE: Our data demonstrate a role for CYP26B1 in regulating RA-dependent signals in activated T cells but not during TGF-β-dependent differentiation to Foxp3+ regulatory T cells. Aberrant expression of CYP26B1 may disturb T cell trafficking and differentiation in the gut and its related lymphoid organs.

  5. Raf/ERK/Nrf2 signaling pathway and MMP-7 expression involvement in the trigonelline-mediated inhibition of hepatocarcinoma cell migration

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    Jung Chun Liao

    2015-12-01

    Full Text Available Background: Trigonelline occurs in many dietary food plants and has been found to have anti-carcinogenic activity. Trigonelline is also found in coffee which is one of the most widely consumed beverages. Many epidemiological studies have reported that coffee consumption has an inverse relationship with the risk of cirrhosis or hepatocellular carcinoma. It would be interesting to investigate whether trigonelline is an ideal chemoprevent agent to prevent cancer progression. Methods: The protein expression was performed by western blotting. The trigonelline content in snow pea (Pisum sativum was analyzed by high-performance liquid chromatography (HPLC. The migratory activity of human hepatocarcinoma cells (Hep3B was assessed by using a wound migration assay. The percentage of each phase in the cell cycle was analyzed on a FACScan flow cytometer. Gene expression was detected by real-time reverse transcriptase-polymerase chain reaction techniques. Native gel analysis was performed to analyze the activity of superoxide dismutase (SOD, catalase and glutathione peroxidase. Results: According to the data of HPLC analysis, P. sativum, which is a popular vegetable, has relatively high content of trigonelline. Our findings suggest that trigonelline is an efficient compound for inhibiting Hep3B cell migration. Trigonelline inhibited the migration of hepatoma cells at concentrations of 75–100 µM without affecting proliferation. Raf/ERK/Nrf2 protein levels and further downstream antioxidative enzymes activity, such as SOD, catalase, and glutathione peroxidase, significantly decreased after treatment with 100 µM of trigonelline for 24 h. The migration inhibition of trigonelline is also related to its ability to regulate the matrix metalloproteinases 7 (MMP-7 gene expression. Conclusions: In this study, protein kinase Cα (PKCα and Raf/ERK/Nrf2 signaling pathway and MMP-7 gene expression were involved in the trigonelline-mediated migration inhibition of Hep

  6. Resveratrol inhibits phosphorylation within the signal transduction and activator of transcription 3 signaling pathway by activating sirtuin 1 in SW1353 chondrosarcoma cells.

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    Jin, Haidong; Chen, Hui; Yu, Kehe; Zhang, Jingdong; Li, Bin; Cai, Ningyu; Pan, Jun

    2016-09-01

    The present study assessed the mechanism by which resveratrol (Res) inhibits the growth of SW1353 chondrosarcoma cells and examined whether sirtuin 1 (Sirt1) activation affects phosphorylation within the signal transduction and activator of transcription 3 (STAT3) signaling pathway. The present study used SW1353 chondrosarcoma cells in the logarithmic phase of growth (control and treatment groups). The latter group was treated with Res at 25 and 50 µmol/l for 24 h, and cell viability, proliferation and apoptosis were analyzed using the cell counting kit‑8 assay, colony counting and Hoechst staining, respectively. The expression levels of caspase‑3, cleaved caspase‑3, B‑cell lymphoma‑2 (BCL‑2), BCL-2 associated X protein (Bax), STAT3 and phosphorylated (p‑)STAT3) were measured by Western blotting. SW1353 cells were transfected with small interfering (si)RNA targeting Sirt1 and the expression levels of Sirt1, STAT3 and p-STAT3 were assessed. Exposure of SW1353 cells to Res reduced cell viability in a dose‑dependent manner (P<0.01). Additionally, cell proliferation was significantly inhibited and the cell nuclei exhibited apoptotic characteristics. Cleaved caspase‑3, Sirt1 and Bax levels were upregulated. The expression levels of BCL‑2 and p‑STAT3 were downregulated. Additionally, the BCL‑2/Bax ratio was reduced compared with the control group. The total STAT3 level was unaffected. Res treatment activated Sirt1, however, in cells transfected with Sirt1‑siRNA, the ability of resveratrol to suppress p‑STAT3 expression was compromised. Overall, it was revealed that Res treatment induced apoptosis, inhibited proliferation and affected phosphorylation within the STAT3 signaling pathway by activating Sirt1 in SW1353 chondrosarcoma cells.

  7. Synthetic high-density lipoprotein-like nanoparticles potently inhibit cell signaling and production of inflammatory mediators induced by lipopolysaccharide binding Toll-like receptor 4.

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    Foit, Linda; Thaxton, C Shad

    2016-09-01

    Toll-like receptor 4 (TLR4) plays a critical role in the innate immune system. Stimulation of TLR4 occurs upon binding lipopolysaccharide (LPS), a component of Gram-negative bacterial cell walls. Due to the potency of the induced inflammatory response, there is a growing interest in agents that can most proximally modulate this LPS/TLR4 interaction to prevent downstream cell signaling events and the production of inflammatory mediators. Building on the natural ability of human high-density lipoprotein (HDL) to bind LPS, we synthesized a suite of HDL-like nanoparticles (HDL-like NP). We identified one HDL-like NP that was particularly effective at decreasing TLR4 signaling caused by addition of purified LPS or Gram-negative bacteria to model human cell lines or primary human peripheral blood cells. The HDL-like NP functioned to inhibit TLR4-dependent inflammatory response to LPS derived from multiple bacterial species. Mechanistically, data show that the NP mainly functions by scavenging and neutralizing the LPS toxin. Taken together, HDL-like NPs constitute a powerful endotoxin scavenger with the potential to significantly reduce LPS-mediated inflammation. PMID:27244690

  8. Flavonoids Identified from Korean Scutellaria baicalensis Georgi Inhibit Inflammatory Signaling by Suppressing Activation of NF-κB and MAPK in RAW 264.7 Cells

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    Gyeong-Eun Hong

    2013-01-01

    Full Text Available Scutellaria baicalensis Georgi has been used as traditional medicine for treating inflammatory diseases, hepatitis, tumors, and diarrhea in Asia. Hence, we investigated the anti-inflammatory effect and determined the molecular mechanism of action of flavonoids isolated from Korean S. baicalensis G. in lipopolysaccharide- (LPS- stimulated RAW 264.7 macrophages. A 3-(4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide assay was performed to examine cytotoxicity of the flavonoids at various concentrations of 10, 40, 70, and 100 µg/mL. No cytotoxicity was observed in RAW 264.7 cells at these concentrations. Furthermore, the flavonoids decreased production of inflammatory mediators such as inducible nitric oxide synthase, cyclooxygenase-2, interleukin-6, and tumor necrosis factor-alpha and inhibited phosphorylation of nuclear factor-kappa B (NF-κB and mitogen-activated protein kinases (MAPKs in LPS-induced RAW 264.7 cells. Moreover, to identify the differentially expressed proteins in RAW 264.7 cells of the control, LPS-treated, and flavonoid-treated groups, two-dimensional gel electrophoresis and mass spectrometry were conducted. The identified proteins were involved in the inflammatory response and included PRKA anchor protein and heat shock protein 70 kD. These findings suggest that the flavonoids isolated from S. baicalensis G. might have anti-inflammatory effects that regulate the expression of inflammatory mediators by inhibiting the NF-κB signaling pathway via the MAPK signaling pathway in RAW 264.7 cells.

  9. Differentiation of human embryonic stem cells into cone photoreceptors through simultaneous inhibition of BMP, TGFβ and Wnt signaling.

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    Zhou, Shufeng; Flamier, Anthony; Abdouh, Mohamed; Tétreault, Nicolas; Barabino, Andrea; Wadhwa, Shashi; Bernier, Gilbert

    2015-10-01

    Cone photoreceptors are required for color discrimination and high-resolution central vision and are lost in macular degenerations, cone and cone/rod dystrophies. Cone transplantation could represent a therapeutic solution. However, an abundant source of human cones remains difficult to obtain. Work performed in model organisms suggests that anterior neural cell fate is induced 'by default' if BMP, TGFβ and Wnt activities are blocked, and that photoreceptor genesis operates through an S-cone default pathway. We report here that Coco (Dand5), a member of the Cerberus gene family, is expressed in the developing and adult mouse retina. Upon exposure to recombinant COCO, human embryonic stem cells (hESCs) differentiated into S-cone photoreceptors, developed an inner segment-like protrusion, and could degrade cGMP when exposed to light. Addition of thyroid hormone resulted in a transition from a unique S-cone population toward a mixed M/S-cone population. When cultured at confluence for a prolonged period of time, COCO-exposed hESCs spontaneously developed into a cellular sheet composed of polarized cone photoreceptors. COCO showed dose-dependent and synergistic activity with IGF1 at blocking BMP/TGFβ/Wnt signaling, while its cone-inducing activity was blocked in a dose-dependent manner by exposure to BMP, TGFβ or Wnt-related proteins. Our work thus provides a unique platform to produce human cones for developmental, biochemical and therapeutic studies and supports the hypothesis that photoreceptor differentiation operates through an S-cone default pathway during human retinal development. PMID:26443633

  10. Henryin, an ent-kaurane diterpenoid, inhibits Wnt signaling through interference with β-catenin/TCF4 interaction in colorectal cancer cells.

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    Xingyao Li

    Full Text Available Aberrant Wnt/β-catenin signaling has been strongly associated with the tumorigenesis of human colorectal cancer. Inhibitors of this pathway may then offer therapeutic strategies as well as chemoprevention for this malignant disease. Henryin is an ent-kaurane diterpenoid isolated from Isodonrubescens var. lushanensis, a plant long been used in folk medicine to prevent inflammation and gastrointestinal disease. In the present study, we report that henryin selectively inhibits the proliferation of human colorectal cancer cells with a GI50 value in the nano-molar range. Microarray analysis and reporter assays showed that henryin worked as a novel antagonist of Wnt signaling pathway. Henryin reduced the expression of Cyclin D1 and C-myc, and induced G1/S phase arrest in HCT116 cells. Concurrently, henryin did not affect the cytosol-nuclear distribution of soluble β-catenin, but impaired the association of β-catenin/TCF4 transcriptional complex likely through directly blocking the binding of β-catenin to TCF4. We also then analyzed the structure-activity relationship among the ent-kaurane type diterpenoids. Our data suggests that henryin, as a novel inhibitor of Wnt signaling, could be a potential candidate for further preclinical evaluation for colon cancer treatment, and as such warrants further exploration.

  11. Puquitinib mesylate (XC-302) induces autophagy via inhibiting the PI3K/AKT/mTOR signaling pathway in nasopharyngeal cancer cells.

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    Wang, Ke-Feng; Yang, Hang; Jiang, Wen-Qi; Li, Su; Cai, Yu-Chen

    2015-12-01

    provides the evidence that XC-302 can induce autophagy in CNE-2, which promotes the program of cell death and inhibits the PI3K/AKT/mTOR signaling pathway. Furthermore, XC-302 also promoted apoptosis in CNE-2 cells, which could be reduced when autophagy was suppressed, meaning that autophagy may interact with apoptosis to induce cell death.

  12. Combined blocked of Ras and mTOR signaling inhibit HCC cell growth%联合靶向Ras和mTOR信号抑制HCC细胞生长

    Institute of Scientific and Technical Information of China (English)

    杨件新; 施超; 施海辉

    2014-01-01

    Objective: To investigate the value of combined blockade Ras and mTOR signaling in the therapy of HCC. Methods: Specific Ras and/or mTOR inhibitors were used to inhibit Ras and mTOR relatively. Cell proliferation was assessed by using the MTT assay. Early apoptosis was detected by Annexin-V-FITC/propidium iodide double staining assay. The ef-fects of the two drugs on HCC were also assessed in xenograft models. Results:Ras inhibitor FTS and mTOR inhibitor all in-hibited HepG2 and Huh-7 cell growth, induced cell apoptosis. Conclusion: Con-target Ras and mTOR could markedly in-hibited HCC cell growth in vitro and in vivo.%目的:探讨联合靶向Ras和mTOR信号在肝细胞癌(hepatocellular carcinoma,HCC)治疗中的价值。方法:四甲基偶氮唑盐(methylthiazolyl tetrazolium,MTT)检测不同浓度Ras抑制剂(farnesylthiosalicylic acid,FTS)和(或)mTOR抑制剂雷帕霉素对肝癌细胞增殖的影响;流式细胞仪检测细胞凋亡;进一步研究两种药物联合对Balb/c小鼠肝癌移植瘤生长的影响。结果:FTS联合雷帕霉素更能抑制HepG2细胞增殖、抑制小鼠肝癌移植瘤的生长,诱导肝癌细胞凋亡。结论:Ras和mTOR信号在HCC治疗中具有联合靶向价值。

  13. Isoalantolactone inhibits the migration and invasion of human breast cancer MDA-MB-231 cells via suppression of the p38 MAPK/NF-κB signaling pathway.

    Science.gov (United States)

    Wang, Jing; Cui, Li; Feng, Liang; Zhang, Zhenhai; Song, Jie; Liu, Dan; Jia, Xiaobin

    2016-09-01

    Isoalantolactone is a bioactive sesquiterpene lactone isolated from the flowering plant Inula helenium L. This study was conducted to assess the anti-migratory and anti-invasive activities of isoalantolactone in MDA-MB-231 cells, and to explore the underlying mechanisms. Wound-healing and Transwell chambers assays demonstrated that isoalantolactone inhibited the adhesion, migration and invasion of MDA-MB-231 cells. The activity and expression of MMP-2 and MMP-9 were downregulated by isoalantolactone in a dose-dependent manner. Additionally, isoalantolactone markedly decreased the p-p38 MAPK level, whereas no significant change in p-ERK1/2 and p-JNK1/2 was noted. The downregulation of MMP-2 and MMP-9 protein expression and suppression of in vitro invasion might be associated with the blockade of p38 MAPK activation. Furthermore, isoalantolactone blocked the translocation of NF-κB p65 from the cytoplasm into the nucleus. These results revealed that isoalantolactone inhibited the adhesion, migration and invasion of MDA-MB-231 cells via suppression of the p38 MAPK/NF-κB signaling pathway, and isoalantolactone might be an alternative treatment for breast cancer. PMID:27461575

  14. Conjugated linoleic acids suppress inflammatory response and ICAM-1 expression through inhibition of NF-κB and MAPK signaling in human bronchial epithelial cells.

    Science.gov (United States)

    Huang, Wen-Chung; Tu, Rong-Syuan; Chen, Ya-Ling; Tsai, Yun-Yun; Lin, Chwan-Fwu; Liou, Chian-Jiun

    2016-04-20

    Conjugated linoleic acids (CLAs) comprise a group of natural unsaturated fatty acids. CLA was reported to have anti-asthma, anti-adiposity, and anti-tumor effects. The present study aimed to evaluate the suppressive effects of cis-9, trans-11-CLA (c9,t11-CLA) on the expression of proinflammatory cytokines and intercellular adhesion molecule 1 (ICAM-1) in TNF-α-stimulated human bronchial epithelial (BEAS-2B) cells. After treating with various doses of c9,t11-CLA (12.5-100 μg ml(-1)), BEAS-2B cells were induced into an inflamed state by adding TNF-α or TNF-α/IL-4. The presence of c9,t11-CLA significantly suppressed the secretion of cytokines IL-6, IL-8, CCL5, and MCP-1. We also found that c9,t11-CLA inhibited ICAM-1 expression, and decreased monocyte adhesion to inflamed bronchial epithelial cells. Interestingly, c9,t11-CLA attenuated the phosphorylation of mitogen-activated protein kinase (MAPK) and down-regulated the activation of nuclear factor-κB (NF-κB). These results suggested that the anti-inflammatory effects of c9,t11-CLA were mediated by inhibiting proinflammatory cytokines, chemokines, and ICAM-1 expression by blocking NF-κB transcription regulation and by attenuating MAPK signaling pathways. PMID:27007063

  15. Resveratrol inhibits hyperglycemia-driven ROS-induced invasion and migration of pancreatic cancer cells via suppression of the ERK and p38 MAPK signaling pathways.

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    Cao, Lei; Chen, Xin; Xiao, Xue; Ma, Qingyong; Li, Wei

    2016-08-01

    Increasing evidence suggests that there is a strong relationship between diabetes mellitus (DM) and pancreatic cancer. Our previous study revealed that hyperglycemia could enhance the invasive and migratory activities of pancreatic cancer cells. Resveratrol, a natural polyphenolic phytoalexin, has many biological and pharmaceutical properties, including antioxidant and anti-tumorigenic capabilities. The aim of the present study was to evaluate whether resveratrol affects hyperglycemia-induced reactive oxygen species (ROS) production as well as the invasion and migration of pancreatic cancer and its underlying mechanisms. Human pancreatic cancer Panc-1 cells were exposed to high glucose condition with or without resveratrol, N-acetylcysteine (NAC, a scavenger of free radicals), PD 98059 (an ERK inhibitor) or SB 203580 (a p38 MAPK inhibitor). The intracellular ROS and hydrogen peroxide (H2O2) were determined using 2,7-dichlorodihydrofluorecein diacetate and H2O2 assay. MTT, wound healing assay and transwell matrigel invasion assay were used to detect the proliferation, migration and invasion potential of cancer cells. The expressions of uPA, E-cadherin and Glut-1 were examined using QT-PCR and western blot analysis at mRNA and protein levels. The activation of p-ERK, p-p38 and p-NF-κB were measured by western blot analysis. The results of the present study showed that resveratrol could significantly decrease high glucose-induced production of ROS and H2O2 in Panc-1 cells. Resveratrol was also able to inhibit high glucose-induced proliferation, migration and invasion of pancreatic cancer cells. High glucose-modulated expression of uPA, E-cadherin and Glut-1 were inhibited by resveratrol. In addition, high glucose-induced activation of ERK and p38 MAPK signaling pathways as well as the transcription factor NF-κB could also be suppressed by resveratrol. Furthermore, resveratrol was able to suppress H2O2-induced migration and invasion abilities of pancreatic cancer

  16. Activation of P2X7 and P2Y11 purinergic receptors inhibits migration and normalizes tumor-derived endothelial cells via cAMP signaling.

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    Avanzato, D; Genova, T; Fiorio Pla, A; Bernardini, M; Bianco, S; Bussolati, B; Mancardi, D; Giraudo, E; Maione, F; Cassoni, P; Castellano, I; Munaron, L

    2016-01-01

    Purinergic signaling is involved in inflammation and cancer. Extracellular ATP accumulates in tumor interstitium, reaching hundreds micromolar concentrations, but its functional role on tumor vasculature and endothelium is unknown. Here we show that high ATP doses (>20 μM) strongly inhibit migration of endothelial cells from human breast carcinoma (BTEC), but not of normal human microvascular EC. Lower doses (1-10 mm result ineffective. The anti-migratory activity is associated with cytoskeleton remodeling and is significantly prevented by hypoxia. Pharmacological and molecular evidences suggest a major role for P2X7R and P2Y11R in ATP-mediated inhibition of TEC migration: selective activation of these purinergic receptors by BzATP mimics the anti-migratory effect of ATP, which is in turn impaired by their pharmacological or molecular silencing. Downstream pathway includes calcium-dependent Adenilyl Cyclase 10 (AC10) recruitment, cAMP release and EPAC-1 activation. Notably, high ATP enhances TEC-mediated attraction of human pericytes, leading to a decrease of endothelial permeability, a hallmark of vessel normalization. Finally, we provide the first evidence of in vivo P2X7R expression in blood vessels of murine and human breast carcinoma. In conclusion, we have identified a purinergic pathway selectively acting as an antiangiogenic and normalizing signal for human tumor-derived vascular endothelium. PMID:27586846

  17. MicroRNA-520a attenuates proliferation of Raji cells through inhibition of AKT1/NF-κB and PERK/eIF2α signaling pathway.

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    Wang, Xiaojuan; Wang, Pei; Zhu, Yan; Zhang, Zhi; Zhang, Jinqian; Wang, Hongwei

    2016-09-01

    Burkitt's lymphoma (BL) is a fast growing cancer of the human lymphatic system, and an extremely invasive B-cell non-Hodgkin's lymphoma. We explored the mechanism of apoptosis in Raji cells associated with the post-transcriptional regulation factors. To confirm that the predicted microRNA-520a (miR-520a) is matched with AKT1, 3' untranslated region (UTR) luciferase activity of AKT1 was used in the assessment. In the presence of the mimics or inhibitors of miR-520a, cell function of Raji, such as proliferation, growth and apoptosis were analyzed. The expression of endoplasmic reticulum (ER) stress‑related proteins were examined. Luciferase reporter analysis showed that miR‑520a leads to decreased activity of luciferase gene fused with AKT1 3'UTR. Therefore, AKT1 is a direct target of miR‑520a. Our data indicated that the mimics of miR‑520a inhibited growth, proliferation of Raji cells and promoted its apoptosis, which was related to downregulation of AKT1, NF‑κB and ER stress response mediated by PERK/eIF2α pathway. On the contrary, the inhibitors of miR‑520a promoted growth, proliferation of Raji cells and inhibited its apoptosis, which was related to AKT1/NF‑κB and PERK/eIF2α pathway. We identified miR‑520a, which specifically binds to AKT1 mRNA 3'UTR. miR‑520a is a crucial mediator for proliferation and ER stress in Raji cells through regulating the AKT1/NF‑κB or PERK/eIF2α signaling pathway. Our findings suggest that targeting miR‑520a is a promising therapeutic strategy in BL. PMID:27461820

  18. Sox17 promotes cell cycle progression and inhibits TGF-beta/Smad3 signaling to initiate progenitor cell behavior in the respiratory epithelium.

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    Alexander W Lange

    Full Text Available The Sry-related high mobility group box transcription factor Sox17 is required for diverse developmental processes including endoderm formation, vascular development, and fetal hematopoietic stem cell maintenance. Expression of Sox17 in mature respiratory epithelial cells causes proliferation and lineage respecification, suggesting that Sox17 can alter adult lung progenitor cell fate. In this paper, we identify mechanisms by which Sox17 influences lung epithelial progenitor cell behavior and reprograms cell fate in the mature respiratory epithelium. Conditional expression of Sox17 in epithelial cells of the adult mouse lung demonstrated that cell cluster formation and respecification of alveolar progenitor cells toward proximal airway lineages were rapidly reversible processes. Prolonged expression of Sox17 caused the ectopic formation of bronchiolar-like structures with diverse respiratory epithelial cell characteristics in alveolar regions of lung. During initiation of progenitor cell behavior, Sox17 induced proliferation and increased the expression of the progenitor cell marker Sca-1 and genes involved in cell cycle progression. Notably, Sox17 enhanced cyclin D1 expression in vivo and activated cyclin D1 promoter activity in vitro. Sox17 decreased the expression of transforming growth factor-beta (TGF-beta-responsive cell cycle inhibitors in the adult mouse lung, including p15, p21, and p57, and inhibited TGF-beta1-mediated transcriptional responses in vitro. Further, Sox17 interacted with Smad3 and blocked Smad3 DNA binding and transcriptional activity. Together, these data show that a subset of mature respiratory epithelial cells retains remarkable phenotypic plasticity and that Sox17, a gene required for early endoderm formation, activates the cell cycle and reinitiates multipotent progenitor cell behavior in mature lung cells.

  19. Combination of NTP with cetuximab inhibited invasion/migration of cetuximab-resistant OSCC cells: Involvement of NF-κB signaling.

    Science.gov (United States)

    Chang, Jae Won; Kang, Sung Un; Shin, Yoo Seob; Seo, Seong Jin; Kim, Yeon Soo; Yang, Sang Sik; Lee, Jong-Soo; Moon, Eunpyo; Lee, Keunho; Kim, Chul-Ho

    2015-01-01

    Although the epidermal growth factor receptor (EGFR) is an established target in head-and-neck cancer (HNC), resistance to EGFR-targeted therapy mediated by various mechanisms has been reported. Therefore, a combination strategy to overcome resistance to EGFR mono-targeted therapy is clinically required. We have previously demonstrated that non-thermal atmospheric pressure plasma (NTP) induces death of various cancer cells, including oral squamous cancer (OSCC) cells. In this study, we report for the first time that combining NTP treatment with cetuximab led to inhibition of migration and invasion in cetuximab-resistant OSCC cells, which could be a promising strategy to overcome resistance to anti-EGFR therapy. NTP induced deactivation of NF-κB in SCCQLL1 cells, but not in MSKQLL1 cells. In addition, NTP increased the expression level of E-cadherin, and decreased those of vimentin, Slug, Snail, matrix metalloproteinase (MMP)-2, -9, and activities of MMPs. Moreover, NF-κB upregulation using cDNA diminished the combination effect of NTP on invasion, migration and related signals. Taken together, these results indicate that the combination of NTP with cetuximab can decrease invasiveness in cetuximab-resistant OSCCs through a novel mechanism involving the NF-κB pathway. These findings show the therapeutic potential of treatment that combines NTP and cetuximab in OSCC. PMID:26655729

  20. Activated human CD4+CD45RO+ memory T-cells indirectly inhibit NLRP3 inflammasome activation through downregulation of P2X7R signalling.

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    Vanessa Beynon

    Full Text Available Inflammasomes are multi-protein complexes that control the production of pro-inflammatory cytokines such as IL-1β. Inflammasomes play an important role in the control of immunity to tumors and infections, and also in autoimmune diseases, but the mechanisms controlling the activation of human inflammasomes are largely unknown. We found that human activated CD4+CD45RO+ memory T-cells specifically suppress P2X7R-mediated NLRP3 inflammasome activation, without affecting P2X7R-independent NLRP3 or NLRP1 inflammasome activation. The concomitant increase in pro-IL-1β production induced by activated memory T-cells concealed this effect. Priming with IFNβ decreased pro-IL-1β production in addition to NLRP3 inflammasome inhibition and thus unmasked the inhibitory effect on NLRP3 inflammasome activation. IFNβ suppresses NLRP3 inflammasome activation through an indirect mechanism involving decreased P2X7R signaling. The inhibition of pro-IL-1β production and suppression of NLRP3 inflammasome activation by IFNβ-primed human CD4+CD45RO+ memory T-cells is partly mediated by soluble FasL and is associated with down-regulated P2X7R mRNA expression and reduced response to ATP in monocytes. CD4+CD45RO+ memory T-cells from multiple sclerosis (MS patients showed a reduced ability to suppress NLRP3 inflammasome activation, however their suppressive ability was recovered following in vivo treatment with IFNβ. Thus, our data demonstrate that human P2X7R-mediated NLRP3 inflammasome activation is regulated by activated CD4+CD45RO+ memory T cells, and provide new information on the mechanisms mediating the therapeutic effects of IFNβ in MS.

  1. Filamin A Expression Negatively Regulates Sphingosine-1-Phosphate-Induced NF-κB Activation in Melanoma Cells by Inhibition of Akt Signaling

    Science.gov (United States)

    Campos, Ludmila S.; Rodriguez, Yamila I.; Leopoldino, Andreia M.; Hait, Nitai C.; Lopez Bergami, Pablo; Castro, Melina G.; Sanchez, Emilse S.; Maceyka, Michael

    2015-01-01

    Sphingosine-1-phosphate (S1P) is a bioactive lipid mediator that regulates many processes in inflammation and cancer. S1P is a ligand for five G-protein-coupled receptors, S1PR1 to -5, and also has important intracellular actions. Previously, we showed that intracellular S1P is involved in tumor necrosis factor alpha (TNF)-induced NF-κB activation in melanoma cell lines that express filamin A (FLNA). Here, we show that extracellular S1P activates NF-κB only in melanoma cells that lack FLNA. In these cells, S1P, but not TNF, promotes IκB kinase (IKK) and p65 phosphorylation, IκBα degradation, p65 nuclear translocation, and NF-κB reporter activity. NF-κB activation induced by S1P was mediated via S1PR1 and S1PR2. Exogenous S1P enhanced the phosphorylation of protein kinase Cδ (PKCδ), and its downregulation reduced S1P-induced the phosphorylation of IKK and p65. In addition, silencing of Bcl10 also inhibited S1P-induced IKK phosphorylation. Surprisingly, S1P reduced Akt activation in melanoma cells that express FLNA, whereas in the absence of FLNA, high phosphorylation levels of Akt were maintained, enabling S1P-mediated NF-κB signaling. In accord, inhibition of Akt suppressed S1P-mediated IKK and p65 phosphorylation and degradation of IκBα. Hence, these results support a negative role of FLNA in S1P-mediated NF-κB activation in melanoma cells through modulation of Akt. PMID:26552704

  2. Ontogeny of catecholamine and adenosine receptor-mediated cAMP signaling of embryonic red blood cells: role of cGMP-inhibited phosphodiesterase 3 and hemoglobin.

    Science.gov (United States)

    Baumann, R; Blass, C; Götz, R; Dragon, S

    1999-12-15

    We have previously shown that the cAMP signaling pathway controls major aspects of embryonic red blood cell (RBC) function in avian embryos (Glombitza et al, Am J Physiol 271:R973, 1996; and Dragon et al, Am J Physiol 271:R982, 1996) that are important for adaptation of the RBC gas transport properties to the progressive hypercapnia and hypoxia of later stages of avian embryonic development. Data about the ontogeny of receptor-mediated cAMP signaling are lacking. We have analyzed the response of primitive and definitive chick embryo RBC harvested from day 3 to 18 of development towards forskolin, beta-adrenergic, and A2 receptor agonists. The results show a strong response of immature definitive and primitive RBC to adenosine A2 and beta-adrenergic receptor agonists, which is drastically reduced in the last stage of development, coincident with the appearance of mature, transcriptionally inactive RBC. Modulation of cGMP-inhibited phosphodiesterase 3 (PDE3) has a controlling influence on cAMP accumulation in definitive RBC. Under physiological conditions, PDE3 is inhibited due to activation of soluble guanylyl cyclase (sGC). Inhibition of sGC with the specific inhibitor ODQ decreases receptor-mediated stimulation of cAMP production; this effect is reversed by the PDE3 inhibitor milrinone. sGC is acitivated by nitric oxide (NO), but we found no evidence for production of NO by erythrocyte NO-synthase. However, embryonic hemoglobin releases NO in an oxygen-linked manner that may activate guanylyl cyclase.

  3. Plumbagin inhibits cell growth and potentiates apoptosis in human gastric cancer cells in vitro through the NF-κB signaling pathway

    Institute of Scientific and Technical Information of China (English)

    Jing LI; Lin SHEN; Fu-rong LU; You QIN; Rui CHEN; Jia LI; Yan LI; Han-zi ZHAN; Yuan-qiao HE

    2012-01-01

    Aim:To investigate the effects and underlying mechanisms of plumbagin,a naphthoquinone derived from medicinal plant Plumbago zeylanica,on human gastric cancer (GC) cells.Methods:Human gastric cancer cell lines SGC-7901,MKN-28,and AGS were used.The cell viability was examined using CCK-8 viability assay.Cell proliferation rate was determined using both clonogenic assay and EdU incorporation assay.Apoptosis was detected via Annexin V/propidium iodide double-labeled flow cytometry.Western blotting was used to assess the expression of both NF-κBregulated gene products and TNF-α-induced activation of p65,IKBα,and IKK.The intracellular location of NF-κB p65 was detected using confocal microscopy.Results:Plumbagin (2.5-40 μmol/L) concentration-dependently reduced the viability of the GC cells.The IC50 value of plumbagin in SGC-7901,MKN-28,and AGS cells was 19.12,13.64,and 10.12 μmol/L,respectively.The compound (5-20 μmol/L) concentrationdependently induced apoptosis of SGC-7901 cells,and potentiated the sensitivity of SGC-7901 cells to chemotherapeutic agents TNFαand cisplatin.The compound (10 μmol/L) downregulated the expression of NF-κB-regulated gene products,including lAP1,XlAP,Bcl2,Bcl-xL,tumor factor (TF),and VEGF.In addition to inhibition of NF-κB p65 nuclear translocation,the compound also suppressed TNF-α-induced phosphorylation of p65 and IKK,and the degradation of IκBα.Conclusion:Plumbagin inhibits cell growth and potentiates apoptosis in human GC cells through the NF-κB pathway.

  4. Activation and Inhibition of The Wnt3A Signaling Pathway in Buffalo (Bubalus bubalis Embryonic Stem Cells: Effects of WNT3A, Bio and Dkk1

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    Mohammad Zandi

    2015-07-01

    Full Text Available Background: This research studies the effects of activation and inhibition of Wnt3A signaling pathway in buffalo (Bubalus bubalis embryonic stem (ES cell-like cells. Materials and Methods: To carry on this experimental study, the effects of activation and inhibition of Wnt3A signaling in buffalo ES cell-like cells were examined using Bio (0.5 mM combined with WNT3A (200 ng/ml, as an activator, and Dickkopf-1 (Dkk1, 250 ng/ml, as an inhibitor, of the pathway. ES cells were cultured up to three weeks in ES cell medium without fibroblast growth factor-2 (FGF-2 and leukemia inhibitory factor (LIF, but in the presence of Bio, WNT3A, Bio+WNT3A and Dkk1. The effects of these supplements were measured on the mean area of ES cell colonies and on the expression levels of a number of important genes related to pluripotency (Oct4, Nanog, Sox2 and c-Myc and the Wnt pathway (β-catenin. ES cell colonies cultured in ES cell medium that contained optimized quantities of LIF and FGF-2 were used as the control. Data were collected for week-1 and week-3 treated cultures. In addition, WNT3A-transfected ES cells were compared with the respective mock-transfected colonies, either alone or in combination with Dkk1 for expression of β-catenin and the pluripotency-related genes. Data were analyzed by ANOVA, and statistical significance was accepted at P<0.05. Results: Among various examined concentrations of Bio (0.5-5 mM, the optimum effect was observed at the 0.5 mM dose as indicated by colony area and expressions of pluripotency- related genes at both weeks-1 and -3 culture periods. At this concentration,the expressions of Nanog, Oct3/4, Sox2, c-Myc and β-catenin genes were nonsignificantly higher compared to the controls. Expressions of these genes were highest in the Bio+WNT3A treated group, followed by the WNT3A and Bio-supplemented groups, and lowest in the Dkk1-treated group. The WNT-transfected colonies showed higher expressions compared to both mock and Dkk1

  5. Inhibition of IL-1R1/MyD88 signalling promotes mesenchymal stem cell-driven tissue regeneration

    OpenAIRE

    Martino, Mikaël M; Maruyama, Kenta; Kuhn, Gisela A.; Satoh, Takashi (Comment); Takeuchi, Osamu; Müller, Ralph; Akira, Shizuo

    2016-01-01

    Tissue injury and the healing response lead to the release of endogenous danger signals including Toll-like receptor (TLR) and interleukin-1 receptor, type 1 (IL-1R1) ligands, which modulate the immune microenvironment. Because TLRs and IL-1R1 have been shown to influence the repair process of various tissues, we explored their role during bone regeneration, seeking to design regenerative strategies integrating a control of their signalling. Here we show that IL-1R1/MyD88 signalling negativel...

  6. A novel synthetic derivative of the natural product berbamine inhibits cell viability and induces apoptosis of human osteosarcoma cells, associated with activation of JNK/AP-1 signaling

    OpenAIRE

    Yang, Fan; Nam, Sangkil; Zhao, Robin; Tian, Yan; Liu, Lucy; Horne, David A.; Jove, Richard

    2013-01-01

    Osteosarcoma is the most common primary bone tumor in children and adolescents. There is a critical need to find more potent drugs for patients with metastatic or recurrent disease. Berbamine (BBM) is a natural compound derived from the Berberis amurensis plants. BBM and its derivatives have been shown to have antitumor effects in several cancers. Here, we report that a novel synthetic berbamine derivative, BBMD3, inhibits cell viability and induces apoptosis of G292, KHOS, and MG-63 human os...

  7. CHRNA7 inhibits cell invasion and metastasis of LoVo human colorectal cancer cells through PI3K/Akt signaling.

    Science.gov (United States)

    Xiang, Tao; Yu, Feng; Fei, Rushan; Qian, Jing; Chen, Wenbin

    2016-02-01

    The α7 neuronal nicotinic receptor gene (CHRNA7) is widely expressed in both the brain and periphery whereas its encoding protein of α7 neuronal acetylcholine receptor (α7nAChR) belongs to the nicotinic acetylcholine receptor family. Considerable evidence suggests that α7nAChR plays an important role in chronic inflammatory and neuropathic pain signaling and thus has been proposed as a potential target for treating cognitive deficits in patients with schizophrenia, attention deficit hyperactivity disorder (ADHD) and Alzheimer's disease. The aim of the present study was to determine the role of endogenous α7nAChR signaling in human colorectal cancer growth and metastasis. pLVX‑CHRNA7 encoding the full length of CHRNA7 was constructed and transfected into LoVo human colorectal cancer cells. Cell proliferation was measured by Cell Counting Kit‑8 (CCK‑8), and cell migration and invasion were detected by Transwell chamber assays. Expression and activity of metastasis‑related metalloproteinases (MMPs) were analyzed by western blotting and gelatin zymography, respectively. Activation of metastasis-related signaling molecules was detected by western blotting. LY294002 was used to specifically block the phosphatidylinositol 3‑kinase/v‑akt murine thymoma viral oncogene homologue (PI3K/Akt) pathway. We showed that concomitantly with an increase in α7nAChR expression after transfection, LoVo cells presented reduced abilities for migration and invasion, which was accompanied by reduced expression levels of MMP‑1 and MMP‑9 as well as activation of the PI3K/Akt signaling pathway. The application of LY294002 restored the migration and invasion abilities of the LoVo cells bearing CHRNA7. Collectively, we conclude that overexpression of CHRNA7 negatively controls colorectal cancer LoVo cell invasion and metastasis via PI3K/Akt pathway activation and may serve as either a diagnostic marker or a therapeutic target for colorectal cancer metastasis.

  8. T cell homeostasis requires G protein-coupled receptor-mediated access to trophic signals that promote growth and inhibit chemotaxis

    OpenAIRE

    Cinalli, Ryan M.; Herman, Catherine E.; Lew, Brian O.; Wieman, Heather L.; Thompson, Craig B.; Rathmell, Jeffrey C.

    2005-01-01

    Signals that regulate T cell homeostasis are not fully understood. G protein-coupled receptors (GPCR), such as the chemokine receptors, may affect homeostasis by direct signaling or by guiding T cell migration to distinct location-restricted signals. Here, we show that blockade of Gαi-associated GPCR signaling by treatment with pertussis toxin led to T cell atrophy and shortened life-span in T cell-replete hosts and prevented T cell homeostatic growth and proliferation in T cell-deficient hos...

  9. Osteoprotegerin inhibits calcification of vascular smooth muscle cell via down regulation of the Notch1-RBP-Jκ/Msx2 signaling pathway.

    Directory of Open Access Journals (Sweden)

    Shaoqiong Zhou

    Full Text Available OBJECTIVE: Vascular calcification is a common pathobiological process which occurs among the elder population and in patients with diabetes and chronic kidney disease. Osteoprotegerin, a secreted glycoprotein that regulates bone mass, has recently emerged as an important regulator of the development of vascular calcification. However, the mechanism is not fully understood. The purpose of this study is to explore novel signaling mechanisms of osteoprotegerin in the osteoblastic differentiation in rat aortic vascular smooth muscle cells (VSMCs. METHODS AND RESULTS: VSMCs were isolated from thoracic aorta of Sprague Dawley rats. Osteoblastic differentiation of VSMCs was induced by an osteogenic medium. We confirmed by Von Kossa staining and direct cellular calcium measurement that mineralization was significantly increased in VSMCs cultured in osteogenic medium; consistent with an enhanced alkaline phosphatase activity. This osteoblastic differentiation in VSMCs was significantly reduced by the addition of osteoprotegerin in a dose responsive manner. Moreover, we identified, by real-time qPCR and western blotting, that expression of Notch1 and RBP-Jκ were significantly up-regulated in VSMCs cultured in osteogenic medium at both the mRNA and protein levels, these effects were dose-dependently abolished by the treatment of osteoprotegerin. Furthermore, we identified that Msx2, a downstream target of the Notch1/RBP-Jκ signaling, was markedly down-regulated by the treatment of osteoprotegerin. CONCLUSION: Osteoprotegerin inhibits vascular calcification through the down regulation of the Notch1-RBP-Jκ signaling pathway.

  10. Isoorientin induces apoptosis through mitochondrial dysfunction and inhibition of PI3K/Akt signaling pathway in HepG2 cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Yuan, Li; Wang, Jing; Xiao, Haifang; Xiao, Chunxia; Wang, Yutang; Liu, Xuebo, E-mail: xueboliu@yahoo.com.cn

    2012-11-15

    Isoorientin (ISO) is a flavonoid compound that can be extracted from several plant species, such as Phyllostachys pubescens, Patrinia, and Drosophyllum lusitanicum; however, its biological activity remains poorly understood. The present study investigated the effects and putative mechanism of apoptosis induced by ISO in human hepatoblastoma cancer (HepG2) cells. The results showed that ISO induced cell death in a dose-dependent manner in HepG2 cells, but no toxicity in human liver cells (HL-7702) and buffalo rat liver cells (BRL-3A) treated with ISO at the indicated concentrations. ISO-induced cell death included apoptosis which characterized by the appearance of nuclear shrinkage, the cleavage of poly (ADP-ribose) polymerase (PARP) and DNA fragmentation. ISO significantly (p < 0.01) increased the Bax/Bcl-2 ratio, disrupted the mitochondrial membrane potential (MMP), increased the release of cytochrome c, activated caspase-3, and enhanced intracellular levels of reactive oxygen species (ROS) and nitric oxide (NO). In addition, ISO effectively inhibited the phosphorylation of Akt and increased FoxO4 expression. The PI3K/Akt inhibitor LY294002 enhanced the apoptosis-inducing effect of ISO. However, LY294002 markedly quenched ROS and NO generation and diminished the protein expression of heme peroxidase enzyme (HO-1) and inducible nitric oxide synthase (iNOS). Furthermore, the addition of a ROS inhibitor (N-acetyl cysteine, NAC) or iNOS inhibitor (N-[3-(aminomethyl) benzyl] acetamidine, dihydrochloride, 1400W) significantly diminished the apoptosis induced by ISO and also blocked the phosphorylation of Akt. These results demonstrated for the first time that ISO induces apoptosis in HepG2 cells and indicate that this apoptosis might be mediated through mitochondrial dysfunction and PI3K/Akt signaling pathway, and has no toxicity in normal liver cells, suggesting that ISO may have good potential as a therapeutic and chemopreventive agent for liver cancer. Highlights:

  11. BDNF/TrkB Signaling as a Potential Novel Target in Pediatric Brain Tumors: Anticancer Activity of Selective TrkB Inhibition in Medulloblastoma Cells.

    Science.gov (United States)

    Thomaz, Amanda; Jaeger, Mariane; Buendia, Marienela; Bambini-Junior, Victorio; Gregianin, Lauro José; Brunetto, Algemir Lunardi; Brunetto, André T; de Farias, Caroline Brunetto; Roesler, Rafael

    2016-07-01

    Medulloblastoma (MB) is the most common malignant pediatric brain tumor. Deregulation of brain-derived neurotrophic factor (BDNF)/tropomyosin-related kinase B (TrkB) signaling has been associated with increased proliferative capabilities, invasiveness, and chemoresistance in several types of cancer. However, the relevance of this pathway in MB remains unknown. Here, we show that the selective TrkB inhibitor N-[2-[[(hexahydro-2-oxo-1H-azepin-3-yl)amino]carbonyl]phenyl]-benzo[b]thiophene-2-carboxamide (ANA-12) markedly reduced the viability and survival of human cell lines representative of different MB molecular subgroups. These findings provide the first evidence supporting further investigation of TrkB inhibition as a potential novel strategy for MB treatment. PMID:26614346

  12. A comparative study on inhibition of total astragalus saponins and astragaloside IV on TNFR1-mediated signaling pathways in arterial endothelial cells.

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    Qin-she Liu

    Full Text Available BACKGROUND: Both total astragalus saponins (AST and it's main component astragaloside IV (ASIV have been used in China as cardiovascular protective medicines. However, the anti-inflammatory activities that are beneficial for cardiovascular health have never been compared directly and the molecular mechanisms remain unresolved. This study was conducted to compare the inhibitory effects of these drugs on TNFα-induced cell responses, related signaling pathways, and the underlying mechanisms in mouse arterial endothelial cells. METHODOLOGY/PRINCIPAL FINDINGS: Real-time qRT-PCR was performed to determine the expression of cell adhesion molecule (CAM genes. Immunofluorescent staining was used to detect the nuclear translocation of transcription factor NF-κB-p65. Western Blot analysis was used to identify TNFα-induced NF-κB-p65 phosphorylation, IκBα degradation, and caspase-3 cleavage. Cell surface proteins were isolated and TNFα receptor-1(TNFR1 expression was determined. The results suggest that both AST and ASIV attenuate TNFα-induced up-regulation of CAMs mRNA and upstream nuclear translocation and phosphorylation of NF-κB-p65. However, TNFR1-mediated IκBα degradation, cleavage of caspase-3 and apoptosis were inhibited only by AST. These differences in the actions of AST and ASIV could be explained by the presence of other components in AST, such as ASII and ASIII, which also had an inhibitory effect on TNFR1-induced IκBα degradation. Moreover, AST, but not ASIV, was able to reduce TNFR1 protein level on the cell surface. Furthermore, mechanistic investigation demonstrated that TNFR1-mediated IκBα degradation was reversed by the use of TAPI-0, an inhibitor of TNFα converting enzyme (TACE, suggesting the involvement of TACE in the modulation of surface TNFR1 level by AST. CONCLUSION: ASIV was not a better inhibitor than AST, at least on the inhibition of TNFα-induced inflammatory responses and TNFR1-mediated signaling pathways in

  13. 4-Hydroxybutenolide impairs cell migration, and invasion of human oral cancer SCC-4 cells via the inhibition of NF-κB and MAPK signaling pathways.

    Science.gov (United States)

    Yu, Fu-Shun; Lin, Meng-Liang; Hsu, Shu-Chun; Yu, Chien-Chih; Huang, Yi-Ping; Kuo, Yueh-Hsiung; Chung, Jing-Gung

    2016-08-01

    4-Hydroxybutenolide (K87), a synthetic compound from furfuryl alcohol via photooxidation, was used to investigate whether it can inhibit mobility, migration and invasion of SCC-4 human oral cancer cells in vitro. Cell viability was measured by flow cytometric assay, the enzymatic activities of MMP-2/9 were assayed by gelatin zymography analysis, the protein levels were assayed by western blotting, confocal laser microscopy and EMSA assay, and the gene expression of MMP-2/-7, FAK and ROCK1 mRNA were assayed by PCR. K87 decreased the percentage of viable cells in dose-dependent manner. K87 suppressed cell mobility, migration and invasion of SCC-4 cells dose-dependently. K87 inhibited the enzymatic activities of MMP-2/9 of SCC-4 cells. Western blot analysis revealed that K87 decreased the protein levels in NF-κBp65, COX-2, ROCK1 and Rho A, MMP-1, -2,- 7, -9, VEGF, GRB2, SOS1, PI3K, PKC, PERK, p-PERK, FAK, MEKK3, MKK7, ERK1/2, JNK1/2, p-p38, p38, p-c-Jun, AKT, TIMP2, but increased the protein levels of iNOS, Ras, IRE-1α, p-c-JNK, p-AKT(308), p-AKT(473) and TIMP1. Results from PCR indicated that K87 inhibited the gene expression of MMP-2/-7, FAK and ROCK1 mRNA. Furthermore, confocal laser microscopy was used to confirm that K87 inhibited the translocation of RHOA and ROCK1 in SCC-4 cells. EMSA assay also show that K87 suppressed the nuclear activation of NF-κB and these effects are time-dependent. Western blotting assay indicated that expression of NF-κBp105, NF-κBp50 and NF-κBp65 proteins were decreased and these effects are time-dependent. Based on these observations, we suggest that K87 may be used as a potential agent for anticancer metastasis of human oral cancer in the future. PMID:27221634

  14. Engineering Cell-Cell Signaling

    OpenAIRE

    Blagovic, Katarina; Gong, Emily S.; Milano, Daniel F.; Natividad, Robert J.; Asthagiri, Anand R

    2013-01-01

    Juxtacrine cell-cell signaling mediated by the direct interaction of adjoining mammalian cells is arguably the mode of cell communication that is most recalcitrant to engineering. Overcoming this challenge is crucial for progress in biomedical applications, such as tissue engineering, regenerative medicine, immune system engineering and therapeutic design. Here, we describe the significant advances that have been made in developing synthetic platforms (materials and devices) and synthetic cel...

  15. Hydrogen sulfide protects against chemical hypoxia-induced injury by inhibiting ROS-activated ERK1/2 and p38MAPK signaling pathways in PC12 cells.

    Directory of Open Access Journals (Sweden)

    Aiping Lan

    Full Text Available Hydrogen sulfide (H(2S has been proposed as a novel neuromodulator and neuroprotective agent. Cobalt chloride (CoCl(2 is a well-known hypoxia mimetic agent. We have demonstrated that H(2S protects against CoCl(2-induced injuries in PC12 cells. However, whether the members of mitogen-activated protein kinases (MAPK, in particular, extracellular signal-regulated kinase1/2(ERK1/2 and p38MAPK are involved in the neuroprotection of H(2S against chemical hypoxia-induced injuries of PC12 cells is not understood. We observed that CoCl(2 induced expression of transcriptional factor hypoxia-inducible factor-1 alpha (HIF-1α, decreased cystathionine-β synthase (CBS, a synthase of H(2S expression, and increased generation of reactive oxygen species (ROS, leading to injuries of the cells, evidenced by decrease in cell viability, dissipation of mitochondrial membrane potential (MMP , caspase-3 activation and apoptosis, which were attenuated by pretreatment with NaHS (a donor of H(2S or N-acetyl-L cystein (NAC, a ROS scavenger. CoCl(2 rapidly activated ERK1/2, p38MAPK and C-Jun N-terminal kinase (JNK. Inhibition of ERK1/2 or p38MAPK or JNK with kinase inhibitors (U0126 or SB203580 or SP600125, respectively or genetic silencing of ERK1/2 or p38MAPK by RNAi (Si-ERK1/2 or Si-p38MAPK significantly prevented CoCl(2-induced injuries. Pretreatment with NaHS or NAC inhibited not only CoCl(2-induced ROS production, but also phosphorylation of ERK1/2 and p38MAPK. Thus, we demonstrated that a concurrent activation of ERK1/2, p38MAPK and JNK participates in CoCl(2-induced injuries and that H(2S protects PC12 cells against chemical hypoxia-induced injuries by inhibition of ROS-activated ERK1/2 and p38MAPK pathways. Our results suggest that inhibitors of ERK1/2, p38MAPK and JNK or antioxidants may be useful for preventing and treating hypoxia-induced neuronal injury.

  16. Rapamycin inhibits BAFF-stimulated cell proliferation and survival by suppressing mTOR-mediated PP2A-Erk1/2 signaling pathway in normal and neoplastic B-lymphoid cells.

    Science.gov (United States)

    Zeng, Qingyu; Zhang, Hai; Qin, Jiamin; Xu, Zhigang; Gui, Lin; Liu, Beibei; Liu, Chunxiao; Xu, Chong; Liu, Wen; Zhang, Shuangquan; Huang, Shile; Chen, Long

    2015-12-01

    B-cell activating factor (BAFF) is involved in not only physiology of normal B cells, but also pathophysiology of aggressive B cells related to malignant and autoimmune diseases. Rapamycin, a lipophilic macrolide antibiotic, has recently shown to be effective in the treatment of human lupus erythematosus. However, how rapamycin inhibits BAFF-stimulated B-cell proliferation and survival has not been fully elucidated. Here, we show that rapamycin inhibited human soluble BAFF (hsBAFF)-induced cell proliferation and survival in normal and B-lymphoid (Raji and Daudi) cells by activation of PP2A and inactivation of Erk1/2. Pretreatment with PD98059, down-regulation of Erk1/2, expression of dominant negative MKK1, or overexpression of wild-type PP2A potentiated rapamycin's suppression of hsBAFF-activated Erk1/2 and B-cell proliferation/viability, whereas expression of constitutively active MKK1, inhibition of PP2A by okadaic acid, or expression of dominant negative PP2A attenuated the inhibitory effects of rapamycin. Furthermore, expression of a rapamycin-resistant and kinase-active mTOR (mTOR-T), but not a rapamycin-resistant and kinase-dead mTOR-T (mTOR-TE), conferred resistance to rapamycin's effects on PP2A, Erk1/2 and B-cell proliferation/viability, implying mTOR-dependent mechanism involved. The findings indicate that rapamycin inhibits BAFF-stimulated cell proliferation/survival by targeting mTOR-mediated PP2A-Erk1/2 signaling pathway in normal and neoplastic B-lymphoid cells. Our data highlight that rapamycin may be exploited for preventing excessive BAFF-induced aggressive B-cell malignancies and autoimmune diseases.

  17. The cell cycle- and insulin-signaling-inhibiting miRNA expression pattern of very small embryonic-like stem cells contributes to their quiescent state.

    Science.gov (United States)

    Maj, Magdalena; Schneider, Gabriela; Ratajczak, Janina; Suszynska, Malwina; Kucia, Magda; Ratajczak, Mariusz Z

    2015-08-01

    Murine Oct4(+), very small embryonic-like stem cells (VSELs), are a quiescent stem cell population that requires a supportive co-culture layer to proliferate and/or to differentiate in vitro. Gene expression studies have revealed that the quiescence of these cells is due to changes in expression of parentally imprinted genes, including genes involved in cell cycle regulation and insulin and insulin-like growth factor signaling (IIS). To investigate the role of microRNAs (miRNAs) in VSEL quiescence, we performed miRNA studies in highly purified VSELs and observed a unique miRNA expression pattern in these cells. Specifically, we observed significant differences in the expression of certain miRNA species (relative to a reference cell population), including (i) miRNA-25_1 and miRNA-19 b, whose downregulation has the effect of upregulating cell cycle checkpoint genes and (ii) miRNA-675-3 p and miRNA-675-5 p, miRNA-292-5 p, miRNA-184, and miRNA-125 b, whose upregulation attenuates IIS. These observations are important for understanding the biology of these cells and for developing efficient ex vivo expansion strategies for VSELs isolated from adult tissues.

  18. The cell cycle- and insulin-signaling-inhibiting miRNA expression pattern of very small embryonic-like stem cells contributes to their quiescent state

    Science.gov (United States)

    Maj, Magdalena; Schneider, Gabriela; Ratajczak, Janina; Suszynska, Malwina; Kucia, Magda

    2015-01-01

    Murine Oct4+, very small embryonic-like stem cells (VSELs), are a quiescent stem cell population that requires a supportive co-culture layer to proliferate and/or to differentiate in vitro. Gene expression studies have revealed that the quiescence of these cells is due to changes in expression of parentally imprinted genes, including genes involved in cell cycle regulation and insulin and insulin-like growth factor signaling (IIS). To investigate the role of microRNAs (miRNAs) in VSEL quiescence, we performed miRNA studies in highly purified VSELs and observed a unique miRNA expression pattern in these cells. Specifically, we observed significant differences in the expression of certain miRNA species (relative to a reference cell population), including (i) miRNA-25_1 and miRNA-19 b, whose downregulation has the effect of upregulating cell cycle checkpoint genes and (ii) miRNA-675-3 p and miRNA-675-5 p, miRNA-292-5 p, miRNA-184, and miRNA-125 b, whose upregulation attenuates IIS. These observations are important for understanding the biology of these cells and for developing efficient ex vivo expansion strategies for VSELs isolated from adult tissues. PMID:25966979

  19. Andrographolide Inhibits Nuclear Factor-κB Activation through JNK-Akt-p65 Signaling Cascade in Tumor Necrosis Factor-α-Stimulated Vascular Smooth Muscle Cells

    Directory of Open Access Journals (Sweden)

    Yu-Ying Chen

    2014-01-01

    Full Text Available Critical vascular inflammation leads to vascular dysfunction and cardiovascular diseases, including abdominal aortic aneurysms, hypertension, and atherosclerosis. Andrographolide is the most active and critical constituent isolated from the leaves of Andrographis paniculata, a herbal medicine widely used for treating anti-inflammation in Asia. In this study, we investigated the mechanisms of the inhibitory effects of andrographolide in vascular smooth muscle cells (VSMCs exposed to a proinflammatory stimulus, tumor necrosis factor-α (TNF-α. Treating TNF-α-stimulated VSMCs with andrographolide suppressed the expression of inducible nitric oxide synthase in a concentration-dependent manner. A reduction in TNF-α-induced c-Jun N-terminal kinase (JNK, Akt, and p65 phosphorylation was observed in andrographolide-treated VSMCs. However, andrographolide affected neither IκBα degradation nor p38 mitogen-activated protein kinase or extracellular signal-regulated kinase 1/2 phosphorylation under these conditions. Both treatment with LY294002, a phosphatidylinositol 3-kinase/Akt inhibitor, and treatment with SP600125, a JNK inhibitor, markedly reversed the andrographolide-mediated inhibition of p65 phosphorylation. In addition, LY294002 and SP600125 both diminished Akt phosphorylation, whereas LY294002 had no effects on JNK phosphorylation. These results collectively suggest that therapeutic interventions using andrographolide can benefit the treatment of vascular inflammatory diseases, and andrographolide-mediated inhibition of NF-κB activity in TNF-α-stimulated VSMCs occurs through the JNK-Akt-p65 signaling cascade, an IκBα-independent mechanism.

  20. Targeting the Metastasis Suppressor, N-Myc Downstream Regulated Gene-1, with Novel Di-2-Pyridylketone Thiosemicarbazones: Suppression of Tumor Cell Migration and Cell-Collagen Adhesion by Inhibiting Focal Adhesion Kinase/Paxillin Signaling.

    Science.gov (United States)

    Wangpu, Xiongzhi; Lu, Jiaoyang; Xi, Ruxing; Yue, Fei; Sahni, Sumit; Park, Kyung Chan; Menezes, Sharleen; Huang, Michael L H; Zheng, Minhua; Kovacevic, Zaklina; Richardson, Des R

    2016-05-01

    Metastasis is a complex process that is regulated by multiple signaling pathways, with the focal adhesion kinase (FAK)/paxillin pathway playing a major role in the formation of focal adhesions and cell motility. N-myc downstream regulated gene-1 (NDRG1) is a potent metastasis suppressor in many solid tumor types, including prostate and colon cancer. Considering the antimetastatic effect of NDRG1 and the crucial involvement of the FAK/paxillin pathway in cellular migration and cell-matrix adhesion, we assessed the effects of NDRG1 on this important oncogenic pathway. In the present study, NDRG1 overexpression and silencing models of HT29 colon cancer and DU145 prostate cancer cells were used to examine the activation of FAK/paxillin signaling and the formation of focal adhesions. The expression of NDRG1 resulted in a marked and significant decrease in the activating phosphorylation of FAK and paxillin, whereas silencing of NDRG1 resulted in an opposite effect. The expression of NDRG1 also inhibited the formation of focal adhesions as well as cell migration and cell-collagen adhesion. Incubation of cells with novel thiosemicarbazones, namely di-2-pyridylketone 4,4-dimethyl-3-thiosemicarbazone and di-2-pyridylketone 4-cyclohexyl-4-methyl-3-thiosemicarbazone, that upregulate NDRG1 also resulted in decreased phosphorylation of FAK and paxillin. The ability of these thiosemicarbazones to inhibit cell migration and metastasis could be mediated, at least in part, through the FAK/paxillin pathway. PMID:26895766

  1. Ginsenoside Rg3 Inhibits Constitutive Activation of NF-κB Signaling in Human Breast Cancer (MDA-MB-231) Cells: ERK and Akt as Potential Upstream Targets

    OpenAIRE

    Kim, Bo-Min; Kim, Do-hee; Park, Jeong-Hill; Surh, Young-Joon; Na, Hye-Kyung

    2014-01-01

    Ginsenoside Rg3, one of the major ingredients of heat-processed ginseng, has been reported to inhibit the growth of various cancer cells. We previously reported that Rg3 inhibited the proliferation and induced apoptosis of breast cancer (MDA-MB-231) cells. In the present study, we have explored the mechanism underlying the anti-proliferative and proapoptotic effects of Rg3 in MDA-MB-231 cells, which have constitutively activated NF-κB and the mutant form of p53. Rg3 inhibited DNA binding and ...

  2. Melittin inhibits tumor angiogenesis modulated by endothelial progenitor cells associated with the SDF-1α/CXCR4 signaling pathway in a UMR-106 osteosarcoma xenograft mouse model.

    Science.gov (United States)

    Qin, Gang; Chen, Yongqiang; Li, Haidong; Xu, Suyang; Li, Yumei; Sun, Jian; Rao, Wu; Chen, Chaowei; Du, Mindong; He, Kaiyi; Ye, Yong

    2016-07-01

    Endothelial progenitor cells (EPCs) are important in tumor angiogenesis. Stromal cell-derived factor-1α (SDF-1α) and its receptor C-X-C chemokine receptor type 4 (CXCR4) are key in stem cell homing. Melittin, a component of bee venom, exerts antitumor activity, however, the underlying mechanisms remain to be elucidated. The present study aimed to assess the effects of melittin on EPCs and angiogenesis in a mouse model of osteosarcoma. UMR‑106 cells and EPCs were treated with various concentrations of melittin and cell viability was determined using the MTT assay. EPC adherence, migration and tube forming ability were assessed. Furthermore, SDF‑1α, AKT and extracellular signal‑regulated kinase (ERK)1/2 expression levels were detected by western blotting. Nude mice were inoculated with UMR‑106 cells to establish an osteosarcoma mouse model. The tumors were injected with melittin, and its effects were assessed by immunohistochemistry and immunofluorescence. Melittin decreased the viability of UMR‑106 cells and EPCs. In addition, it decreased EPC adhesion, migration and tube formation when compared with control and SDF‑1α‑treated cells. Melittin decreased the expression of phosphorylated (p)‑AKT, p‑ERK1/2, SDF‑1α and CXCR4 in UMR‑106 cells and EPCs when compared with the control. The proportions of cluster of differentiation (CD)34/CD133 double‑positive cells were 16.4±10.4% in the control, and 7.0±4.4, 2.9±1.2 and 1.3±0.3% in tumors treated with 160, 320 and 640 µg/kg melittin per day, respectively (P<0.05). At 11 days, melittin reduced the tumor size when compared with that of the control (control, 4.8±1.3 cm3; melittin, 3.2±0.6, 2.6±0.5, and 2.0±0.2 cm3 for 160, 320 and 640 µg/kg, respectively; all P<0.05). Melittin decreased the microvessel density, and SDF‑1α and CXCR4 protein expression levels in the tumors. Melittin may decrease the effect of osteosarcoma on EPC‑mediated angiogenesis, possibly via inhibition

  3. Resveratrol Inhibits Inflammatory Responses via the Mammalian Target of Rapamycin Signaling Pathway in Cultured LPS-Stimulated Microglial Cells

    OpenAIRE

    Zhong, Lian-Mei; Zong, Yi; Sun, Lin; Guo, Jia-Zhi; Zhang, Wei; He, Ying; Song, Rui; Wang, Wen-Min; Xiao, Chun-jie; Lu, Di

    2012-01-01

    Background Resveratrol have been known to possess many pharmacological properties including antioxidant, cardioprotective and anticancer effects. Although current studies indicate that resveratrol produces neuroprotection against neurological disorders, the precise mechanisms for its beneficial effects are still not fully understood. We investigate the effect of anti-inflammatory and mechamisms of resveratrol by using lipopolysaccharide (LPS)-stimulated murine microglial BV-2 cells. Methodolo...

  4. Mesenchymal stromal cells mediate Aspergillus hyphal extract-induced allergic airway inflammation by inhibition of the Th17 signaling pathway.

    Science.gov (United States)

    Lathrop, Melissa J; Brooks, Elice M; Bonenfant, Nick R; Sokocevic, Dino; Borg, Zachary D; Goodwin, Meagan; Loi, Roberto; Cruz, Fernanda; Dunaway, Chad W; Steele, Chad; Weiss, Daniel J

    2014-02-01

    Systemic administration of mesenchymal stromal cells (MSCs) suppresses airway inflammation and methacholine-induced airway hyper-responsiveness (AHR) in mouse models of T helper cell (Th) type 2-mediated eosinophilic allergic airway inflammation (AAI); however, the efficacy of MSCs in mouse models of severe Th17-mediated neutrophilic AAI has not yet been demonstrated. We assessed MSC effects in a mouse model of mixed Th2/Th17 AAI produced by mucosal exposure to Aspergillus fumigatus hyphal extract (AHE). Following sensitization produced by oropharyngeal AHE administration, systemic (tail vein) administration of syngeneic MSCs on the first day of challenge significantly reduced acute AHR predominantly through reduction of Th17-mediated airway inflammation. In parallel experiments, MSCs also mitigated AHR when administered during recurrent challenge 10 weeks after initial sensitization and challenge through reduction in systemic Th17-mediated inflammation. Investigation into potential mechanistic actions of MSCs in this model demonstrated that although T regulatory cells were increased in all AHE-treated mice, MSC administration did not alter T regulatory cell numbers in either the acute or recurrent model. Differential induction of interleukin-17a secretion was observed in ex vivo restimulation of mediastinal lymph node mixed-cell cytokine analyses. Although the mechanisms by which MSCs act to decrease inflammation and AHR in this model are not yet fully elucidated, decrease in Th17-mediated airway inflammation appears to play a significant role. These results provide a basis for further investigations of MSC administration as a potential therapeutic approach for severe refractory neutrophilic asthma. PMID:24436442

  5. Hydrogen sulfide-releasing naproxen suppresses colon cancer cell growth and inhibits NF-κB signaling

    Directory of Open Access Journals (Sweden)

    Kodela R

    2015-08-01

    Full Text Available Ravinder Kodela,1 Niharika Nath,2 Mitali Chattopadhyay,1 Diandra E Nesbitt,1 Carlos A Velázquez-Martínez,3 Khosrow Kashfi11Department of Physiology, Pharmacology and Neuroscience, Sophie Davis School of Biomedical Education, City University of New York Medical School, 2Department of Life Sciences, New York Institute of Technology, New York, NY, USA; 3Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, AB, Canada Abstract: Colorectal cancer (CRC is the second leading cause of death due to cancer and the third most common cancer in men and women in the USA. Nuclear factor kappa B (NF-κB is known to be activated in CRC and is strongly implicated in its development and progression. Therefore, activated NF-κB constitutes a bona fide target for drug development in this type of malignancy. Many epidemiological and interventional studies have established nonsteroidal anti-inflammatory drugs (NSAIDs as a viable chemopreventive strategy against CRC. Our previous studies have shown that several novel hydrogen sulfide-releasing NSAIDs are promising anticancer agents and are safer derivatives of NSAIDs. In this study, we examined the growth inhibitory effect of a novel H2S-releasing naproxen (HS-NAP, which has a repertoire as a cardiovascular-safe NSAID, for its effects on cell proliferation, cell cycle phase transitions, and apoptosis using HT-29 human colon cancer cells. We also investigated its effect as a chemopreventive agent in a xenograft mouse model. HS-NAP suppressed the growth of HT-29 cells by induction of G0/G1 arrest and apoptosis and downregulated NF-κB. Tumor xenografts in mice were significantly reduced in volume. The decrease in tumor mass was associated with a reduction of cell proliferation, induction of apoptosis, and decreases in NF-κB levels in vivo. Therefore, HS-NAP demonstrates strong anticancer potential in CRC. Keywords: nonsteroidal anti-inflammatory drugs, cell cycle, apoptosis, xenograft, NF

  6. Growth arrest- and DNA-damage-inducible 45beta gene inhibits c-Jun N-terminal kinase and extracellular signal-regulated kinase and decreases IL-1beta-induced apoptosis in insulin-producing INS-1E cells

    DEFF Research Database (Denmark)

    Larsen, Claus Morten; Døssing, M G; Papa, S;

    2006-01-01

    IL-1beta is a candidate mediator of apoptotic beta cell destruction, a process that leads to type 1 diabetes and progression of type 2 diabetes. IL-1beta activates beta cell c-Jun N-terminal kinase (JNK), extracellular signal-regulated kinase (ERK) and p38, all of which are members of the mitogen......-activated protein kinase (MAPK) family. Inhibition of JNK prevents IL-1beta-mediated beta cell destruction. In mouse embryo fibroblasts and 3DO T cells, overexpression of the gene encoding growth arrest and DNA-damage-inducible 45beta (Gadd45b) downregulates pro-apoptotic JNK signalling. The aim of this study...

  7. Yeast Ca(2+)-signal transduction inhibitors isolated from Dominican amber prevent the degranulation of RBL-2H3 cells through the inhibition of Ca(2+)-influx.

    Science.gov (United States)

    Abe, Tomomi; Kobayashi, Miki; Okawa, Yusuke; Inui, Tomoki; Yoshida, Jun; Higashio, Hironori; Shinden, Hisao; Uesugi, Shota; Koshino, Hiroyuki; Kimura, Ken-Ichi

    2016-09-01

    A new norlabdane compound, named kujigamberol has previously been isolated from Kuji amber (but not from Baltic amber) by activity guided fractionation. However, there has been no study of biological compounds in Dominican amber. Biological activities were examined using the hypersensitive mutant yeast (zds1Δ erg3Δ pdr1Δ pdr3Δ) with respect to Ca(2+)-signal transduction, enzymes and rat basophilic leukemia (RBL)-2H3 cells. The structures were elucidated on the basis of spectral analysis including high resolution (HR)-EI-MS, 1D NMR and 2D NMR. Three diterpenoid compounds, 5(10)-halimen-15-oic acid (1), 3-cleroden-15-oic acid (2) and 8-labden-15-oic acid (3), which are different from the bioactive compounds in Kuji and Baltic ambers, were isolated from Dominican amber. They inhibited both calcineurin (CN) (IC50=40.0, 21.2 and 34.2μM) and glycogen synthase kinase-3β (GSK-3β) (IC50=48.9, 43.8 and 41.1μM) which are involved in the growth restored activity against the mutant yeast. The most abundant compound 2 showed inhibitory activity against both degranulation and Ca(2+)-influx in RBL-2H3 cells. The compounds having the growth restoring activity against the mutant yeast have potential as anti-allergic compounds.

  8. Yeast Ca(2+)-signal transduction inhibitors isolated from Dominican amber prevent the degranulation of RBL-2H3 cells through the inhibition of Ca(2+)-influx.

    Science.gov (United States)

    Abe, Tomomi; Kobayashi, Miki; Okawa, Yusuke; Inui, Tomoki; Yoshida, Jun; Higashio, Hironori; Shinden, Hisao; Uesugi, Shota; Koshino, Hiroyuki; Kimura, Ken-Ichi

    2016-09-01

    A new norlabdane compound, named kujigamberol has previously been isolated from Kuji amber (but not from Baltic amber) by activity guided fractionation. However, there has been no study of biological compounds in Dominican amber. Biological activities were examined using the hypersensitive mutant yeast (zds1Δ erg3Δ pdr1Δ pdr3Δ) with respect to Ca(2+)-signal transduction, enzymes and rat basophilic leukemia (RBL)-2H3 cells. The structures were elucidated on the basis of spectral analysis including high resolution (HR)-EI-MS, 1D NMR and 2D NMR. Three diterpenoid compounds, 5(10)-halimen-15-oic acid (1), 3-cleroden-15-oic acid (2) and 8-labden-15-oic acid (3), which are different from the bioactive compounds in Kuji and Baltic ambers, were isolated from Dominican amber. They inhibited both calcineurin (CN) (IC50=40.0, 21.2 and 34.2μM) and glycogen synthase kinase-3β (GSK-3β) (IC50=48.9, 43.8 and 41.1μM) which are involved in the growth restored activity against the mutant yeast. The most abundant compound 2 showed inhibitory activity against both degranulation and Ca(2+)-influx in RBL-2H3 cells. The compounds having the growth restoring activity against the mutant yeast have potential as anti-allergic compounds. PMID:27491756

  9. Inhibition of apoptotic signaling in spermine-treated vascular smooth muscle cells by a novel glutathione precursor

    OpenAIRE

    Sinha-Hikim, Indrani; Shen, Ruoqing; Kovacheva, Ekaterina; Crum, Albert; Vaziri, Nosratola D.; Norris, Keith C.

    2010-01-01

    Chronic kidney disease (CKD) is a public health problem, mediated by hemodynamic and non-hemodynamic events including oxidative stress. We investigated the effect of two glutathione (GSH) precursors, N-acetyl-cysteine (NAC) and cystine as the physiologic carrier of cysteine in GSH with added selenomethionine (F1) in preventing spermine (uremic toxin) induced apoptosis in cultured human aortic vascular smooth muscle cells (VSMC). VSMCs exposed to spermine (15 μM) with or without antioxidants (...

  10. Inhibition of biofilm development and spoilage potential of Shewanella baltica by quorum sensing signal in cell-free supernatant from Pseudomonas fluorescens.

    Science.gov (United States)

    Zhao, Aifei; Zhu, Junli; Ye, Xiaofeng; Ge, Yangyang; Li, Jianrong

    2016-08-01

    The objective of this study was to in vitro evaluate the effect of a cell-free supernatant (CFS) containing quorum sensing (QS) signal of Pseudomonas fluorescens on the growth, biofilm development and spoilage potential of Shewanella baltica, and preliminarily assess the interactive influences of various chemically synthesized autoinducers on spoilage phenotypes of S. baltica. PF01 strain isolated from spoiled Pseudosciaen crocea was identified P. fluorescens. The addition of 25% and 50% CFS to S. baltica culture had no effect on the growth rate during the lag and exponential phase, however, caused cell decline during the stationary phase. The presence of CFS from P. fluorescens significantly inhibited biofilm development, and greatly decreased the production of trimethylamine (TMA) and biogenic amino in S. baltica. Various signal molecules of QS in the CFS of P. fluorescens culture were detected, including seven N-acyl-l-homoserine lactones (AHLs), autoinducer-2 (AI-2) and two diketopiperazines (DKPs). Exogenous supplement of synthesized seven AHLs containing in the CFS decreased biofilm formation and TMA production in S. baltica, while exposure to exogenous cyclo-(l-Pro-l-Leu) was showed to promote spoilage potential, which revealed that S. baltica also sense the two QS molecules. Furthermore, the stimulating effect of cyclo-(l-Pro-l-Leu) was affected when AHL was simultaneously added, suggesting that the inhibitory activity of spoilage phenotypes in S. baltica might be attributed to a competitive effect of these QS compounds in the CFS of P. fluorescens. The present studies provide a good basis for future research on the role of QS in the regulation of spoilage microbial flora. PMID:27149651

  11. Resveratrol inhibits mTOR signaling by targeting DEPTOR

    Science.gov (United States)

    Liu, Feng

    2011-01-01

    Resveratrol (RSV, trans-3,4,5-Trihydroxystilbene), a type of polyphenol originally found in red wines, shows a great promise for the treatment of cancer, aging, type 2 diabetes and cardiovascular diseases. Recent studies suggest that suppressing the signaling pathway mediated by mTOR, a well-known energy sensor that integrates various hormonal, nutrient and environmental signals to regulate cell growth, metabolism and survival, could play an important role in mediating the beneficial effect of RSV. The underlying mechanisms by which RSV inhibits mTOR signaling remain elusive, but our recent studies show that RSV inhibits amino acid-stimulated mTOR signaling in C2C12 fibroblasts via a Sirt1- and AMPK-independent mechanism. RSV treatment has no effect on the expression levels of mTOR, raptor and DEPTOR, but greatly promotes the interaction between mTOR and its inhibitor DEPTOR. Our results reveal a novel mechanism by which RSV inhibits mTOR signaling and its function. PMID:21966552

  12. Adiponectin promotes VEGF-C-dependent lymphangiogenesis by inhibiting miR-27b through a CaMKII/AMPK/p38 signaling pathway in human chondrosarcoma cells.

    Science.gov (United States)

    Huang, Chun-Yin; Chang, An-Chen; Chen, Hsien-Te; Wang, Shih-Wei; Lo, Yuan-Shun; Tang, Chih-Hsin

    2016-09-01

    Chondrosarcoma is the second most frequently occurring type of bone malignancy characterized by distant metastatic propensity. Vascular endothelial growth factor-C (VEGF-C) is the major lymphangiogenic factor, and makes crucial contributions to tumour lymphangiogenesis and lymphatic metastasis. Adiponectin is a protein hormone secreted predominantly by differentiated adipocytes. In recent years, adiponectin has also been indicated as facilitating tumorigenesis, angiogenesis and metastasis. However, the effect of adiponectin on VEGF-C regulation and lymphangiogenesis in chondrosarcoma has remained largely a mystery. In the present study, we have shown a clinical correlation between adiponectin and VEGF-C, as well as tumour stage, in human chondrosarcoma tissues. We further demonstrated that adiponectin promoted VEGF-C expression and secretion in human chondrosarcoma cells. The conditioned medium from adiponectin-treated cells significantly induced tube formation and migration of human lymphatic endothelial cells. In addition, adiponectin knock down inhibited lymphangiogenesis in vitro and in vivo We also found that adiponectin-induced VEGF-C is mediated by the calmodulin-dependent protein kinase II (CaMKII), AMP-activated protein kinase (AMPK) and p38 signaling pathway. Furthermore, the expression of miR-27b was negatively regulated by adiponectin via the CaMKII, AMPK and p38 cascade. The present study is the first to describe the mechanism of adiponectin-promoted lymphangiogenesis by up-regulating VEGF-C expression in chondrosarcomas. Thus, adiponectin could serve as a therapeutic target in chondrosarcoma metastasis and lymphangiogenesis. PMID:27252405

  13. Adiponectin promotes VEGF-C-dependent lymphangiogenesis by inhibiting miR-27b through a CaMKII/AMPK/p38 signaling pathway in human chondrosarcoma cells.

    Science.gov (United States)

    Huang, Chun-Yin; Chang, An-Chen; Chen, Hsien-Te; Wang, Shih-Wei; Lo, Yuan-Shun; Tang, Chih-Hsin

    2016-09-01

    Chondrosarcoma is the second most frequently occurring type of bone malignancy characterized by distant metastatic propensity. Vascular endothelial growth factor-C (VEGF-C) is the major lymphangiogenic factor, and makes crucial contributions to tumour lymphangiogenesis and lymphatic metastasis. Adiponectin is a protein hormone secreted predominantly by differentiated adipocytes. In recent years, adiponectin has also been indicated as facilitating tumorigenesis, angiogenesis and metastasis. However, the effect of adiponectin on VEGF-C regulation and lymphangiogenesis in chondrosarcoma has remained largely a mystery. In the present study, we have shown a clinical correlation between adiponectin and VEGF-C, as well as tumour stage, in human chondrosarcoma tissues. We further demonstrated that adiponectin promoted VEGF-C expression and secretion in human chondrosarcoma cells. The conditioned medium from adiponectin-treated cells significantly induced tube formation and migration of human lymphatic endothelial cells. In addition, adiponectin knock down inhibited lymphangiogenesis in vitro and in vivo We also found that adiponectin-induced VEGF-C is mediated by the calmodulin-dependent protein kinase II (CaMKII), AMP-activated protein kinase (AMPK) and p38 signaling pathway. Furthermore, the expression of miR-27b was negatively regulated by adiponectin via the CaMKII, AMPK and p38 cascade. The present study is the first to describe the mechanism of adiponectin-promoted lymphangiogenesis by up-regulating VEGF-C expression in chondrosarcomas. Thus, adiponectin could serve as a therapeutic target in chondrosarcoma metastasis and lymphangiogenesis.

  14. Marine bromophenol bis(2,3-dibromo-4,5-dihydroxybenzyl) ether, represses angiogenesis in HUVEC cells and in zebrafish embryos via inhibiting the VEGF signal systems.

    Science.gov (United States)

    Qi, Xin; Liu, Ge; Qiu, Lin; Lin, Xiukun; Liu, Ming

    2015-10-01

    Bis(2,3-dibromo-4,5-dihydroxybenzyl) ether (BDDE) is a bromophenol compound derived from marine algae. Our previous reports have shown that BDDE possessed anticancer activity in vitro. However, its antiangiogenesis activity and possible mechanisms remain unclear. The present study demonstrated that BDDE displayed in vitro antiangiogenesis capabilities by significantly inhibiting HUVEC cells proliferation, migration, and tube formation, without any effect on the preformed vascular tube. Western blot analysis revealed that BDDE decreased the protein level of VEGF and VEGFR but not that of EGFR, FGFR, and IGFR. In addition, BDDE inactivated the VEGF downstream signaling molecules including mTOR and Src, whereas activated Akt and ERK. Moreover, BDDE blocked subintestinal vessel formation in zebrafish embryos in vivo and showed toxicity under high concentrations of BDDE. The results of this present study indicated that BDDE, which has unique chemical structure different from current antiangiogenesis agents, could be used as a potential drug candidate for cancer prevention and therapy. PMID:26463632

  15. NF-kappa B signaling pathway is involved in growth inhibition, G2/M arrest and apoptosis induced by Trichostatin A in human tongue carcinoma cells

    NARCIS (Netherlands)

    Yao, Jun; Duan, Li; Fan, Mingwen; Wu, Xinxing

    2006-01-01

    The HDAC inhibitor Trichostatin A (TSA) exhibits antiturnour activity in various tumour cells. However, little is known about the effect of TSA on growth of human tongue carcinoma cells. In this study, we observed that TSA concentration-dependently inhibited growth of human tongue carcinoma Tca8113

  16. Suppressing the formation of lipid raft-associated Rac1/PI3K/Akt signaling complexes by curcumin inhibits SDF-1α-induced invasion of human esophageal carcinoma cells.

    Science.gov (United States)

    Lin, Meng-Liang; Lu, Yao-Cheng; Chen, Hung-Yi; Lee, Chuan-Chun; Chung, Jing-Gung; Chen, Shih-Shun

    2014-05-01

    Stromal cell-derived factor-1α (SDF-1α) is a ligand for C-X-C chemokine receptor type 4 (CXCR4), which contributes to the metastasis of cancer cells by promoting cell migration. Here, we show that the SDF-1α/CXCR4 axis can significantly increase invasion of esophageal carcinoma (EC) cells. We accomplished this by examining the effects of CXCR4 knockdown as well as treatment with a CXCR4-neutralizing antibody and the CXCR4-specific inhibitor AMD3100. Curcumin suppressed SDF-1α-induced cell invasion and matrix metalloproteinase-2 (MMP-2) promoter activity, cell surface localization of CXCR4 at lipid rafts, and lipid raft-associated ras-related C3 botulinum toxin substrate 1 (Rac1)/phosphatidylinositol 3-kinase (PI3K) p85α/Akt signaling. Curcumin inhibited SDF-1α-induced cell invasion by suppressing the Rac1-PI3K signaling complex at lipid rafts but did not abrogate lipid raft formation. We further demonstrate that the attenuation of lipid raft-associated Rac1 activity by curcumin was critical for the inhibition of SDF-1α-induced PI3K/Akt/NF-κB activation, cell surface localization of CXCR4 at lipid rafts, MMP-2 promoter activity, and cell invasion. Collectively, our results indicate that curcumin inhibits SDF-1α-induced EC cell invasion by suppressing the formation of the lipid raft-associated Rac1-PI3K-Akt signaling complex, the localization of CXCR4 with lipid rafts at the cell surface, and MMP-2 promoter activity, likely through the inhibition of Rac1 activity.

  17. Silymarin suppresses the PGE2 -induced cell migration through inhibition of EP2 activation; G protein-dependent PKA-CREB and G protein-independent Src-STAT3 signal pathways.

    Science.gov (United States)

    Woo, Seon Min; Min, Kyoung-Jin; Chae, In Gyeong; Chun, Kyung-Soo; Kwon, Taeg Kyu

    2015-03-01

    Silymarin has been known as a chemopreventive agent, and possesses multiple anti-cancer activities including induction of apoptosis, inhibition of proliferation and growth, and blockade of migration and invasion. However, whether silymarin could inhibit prostaglandin (PG) E2 -induced renal cell carcinoma (RCC) migration and what are the underlying mechanisms are not well elucidated. Here, we found that silymarin markedly inhibited PGE2 -stimulated migration. PGE2 induced G protein-dependent CREB phosphorylation via protein kinase A (PKA) signaling, and PKA inhibitor (H89) inhibited PGE2 -mediated migration. Silymarin reduced PGE2 -induced CREB phosphorylation and CRE-promoter activity. PGE2 also activated G protien-independent signaling pathways (Src and STAT3) and silymarin reduced PGE2 -induced phosphorylation of Src and STAT3. Inhibitor of Src (Saracatinib) markedly reduced PGE2 -mediated migration. We found that EP2, a PGE2 receptor, is involved in PGE2 -mediated cell migration. Down regulation of EP2 by EP2 siRNA and EP2 antagonist (AH6809) reduced PGE2 -inudced migration. In contrast, EP2 agonist (Butaprost) increased cell migration and silymarin effectively reduced butaprost-mediated cell migration. Moreover, PGE2 increased EP2 expression through activation of positive feedback mechanism, and PGE2 -induced EP2 expression, as well as basal EP2 levels, were reduced in silymarin-treated cells. Taken together, our study demonstrates that silymarin inhibited PGE2 -induced cell migration through inhibition of EP2 signaling pathways (G protein dependent PKA-CREB and G protein-independent Src-STAT3).

  18. Dependence of Wilms tumor cells on signaling through insulin-like growth factor 1 in an orthotopic xenograft model targetable by specific receptor inhibition

    DEFF Research Database (Denmark)

    Bielen, Aleksandra; Box, Gary; Perryman, Lara;

    2012-01-01

    pathway inactivation. By contrast, Wilms tumor cells established orthotopically within the kidney were histologically accurate and exhibited significantly elevated insulin-like growth factor-mediated signaling, and growth was significantly reduced on treatment with NVP-AEW541 in parallel with signaling...

  19. IL-1beta-induced pro-apoptotic signalling is facilitated by NCAM/FGF receptor signalling and inhibited by the C3d ligand in the INS-1E rat beta cell line

    DEFF Research Database (Denmark)

    Petersen, L G; Størling, J; Heding, P;

    2006-01-01

    AIMS/HYPOTHESIS: IL-1beta released from immune cells induces beta cell pro-apoptotic signalling via mitogen-activated protein kinases (MAPKs) and nuclear factor-kappaB (NF-kappaB). In neurons, the neural cell adhesion molecule (NCAM) signals to several elements involved in IL-1beta-induced pro......-apoptotic signalling in beta cells. Pancreatic beta cells express NCAM, but its biological effects in these cells are unclear. The aim of this study was to investigate whether there is cross-talk between NCAM signalling and cytokine-induced pro-apoptotic signalling. MATERIALS AND METHODS: Western blotting was used...... to investigate levels of NCAM and inducible nitric oxide synthase, phosphorylation of Src and MAPKs, and cleavage of caspase-3. MAPK activity was investigated with an in vitro kinase assay. Apoptosis was detected by cleaved caspase-3 and a Cell Death Detection ELISA(plus) assay. NCAM-induced fibroblast growth...

  20. Caffeine inhibits the activation of hepatic stellate cells induced by acetaldehyde via adenosine A2A receptor mediated by the cAMP/PKA/SRC/ERK1/2/P38 MAPK signal pathway.

    Directory of Open Access Journals (Sweden)

    He Wang

    Full Text Available Hepatic stellate cell (HSC activation is an essential event during alcoholic liver fibrosis. Evidence suggests that adenosine aggravates liver fibrosis via the adenosine A2A receptor (A2AR. Caffeine, which is being widely consumed during daily life, inhibits the action of adenosine. In this study, we attempted to validate the hypothesis that caffeine influences acetaldehyde-induced HSC activation by acting on A2AR. Acetaldehyde at 50, 100, 200, and 400 μM significantly increased HSC-T6 cells proliferation, and cell proliferation reached a maximum at 48 h after exposure to 200 μM acetaldehyde. Caffeine and the A2AR antagonist ZM241385 decreased the cell viability and inhibited the expression of procollagen type I and type III in acetaldehyde-induced HSC-T6 cells. In addition, the inhibitory effect of caffeine on the expression of procollagen type I was regulated by A2AR-mediated signal pathway involving cAMP, PKA, SRC, and ERK1/2. Interestingly, caffeine's inhibitory effect on the expression of procollagen type III may depend upon the A2AR-mediated P38 MAPK-dependent pathway.Caffeine significantly inhibited acetaldehyde-induced HSC-T6 cells activation by distinct A2AR mediated signal pathway via inhibition of cAMP-PKA-SRC-ERK1/2 for procollagen type I and via P38 MAPK for procollagen type III.

  1. Response inhibition signals and miscoding of direction in dorsomedial striatum

    Directory of Open Access Journals (Sweden)

    Daniel W Bryden

    2012-09-01

    Full Text Available The ability to inhibit action is critical for everyday behavior and is affected by a variety of disorders. Behavioral control and response inhibition is thought to depend on a neural circuit that includes the dorsal striatum, yet the neural signals that lead to response inhibition and its failure are unclear. To address this issue, we recorded from neurons in rat dorsomedial striatum (mDS in a novel task in which rats responded to a spatial cue that signaled that reward would be delivered either to the left or to the right. On 80% of trials rats were instructed to respond in the direction cued by the light (GO. On 20% of trials a second light illuminated instructing the rat to refrain from making the cued movement and move in the opposite direction (STOP. Many neurons in mDS encoded direction, firing more or less strongly for GO movements made ipsilateral or contralateral to the recording electrode. Neurons that fired more strongly for contralateral GO responses were more active when rats were faster, showed reduced activity on STOP trials, and miscoded direction on errors, suggesting that when these neurons were overly active, response inhibition failed. Neurons that decreased firing for contralateral movement were excited during trials in which the rat was required to stop the ipsilateral movement. For these neurons activity was reduced when errors were made and was negatively correlated with movement time suggesting that when these neurons were less active on STOP trials, response inhibition failed. Finally, the activity of a significant number of neurons represented a global inhibitory signal, firing more strongly during response inhibition regardless of response direction. Breakdown by cell type suggests that putative medium spiny neurons tended to fire more strongly under STOP trials, whereas putative interneurons exhibited both activity patterns. 

  2. Inhibition of mitochondrial genome expression triggers the activation of CHOP-10 by a cell signaling dependent on the integrated stress response but not the mitochondrial unfolded protein response.

    Science.gov (United States)

    Michel, Sebastien; Canonne, Morgane; Arnould, Thierry; Renard, Patricia

    2015-03-01

    Mitochondria-to-nucleus communication, known as retrograde signaling, is important to adjust the nuclear gene expression in response to organelle dysfunction. Among the transcription factors described to respond to mitochondrial stress, CHOP-10 is activated by respiratory chain inhibition, mitochondrial accumulation of unfolded proteins and mtDNA mutations. In this study, we show that altered/impaired expression of mtDNA induces CHOP-10 expression in a signaling pathway that depends on the eIF2α/ATF4 axis of the integrated stress response rather than on the mitochondrial unfolded protein response.

  3. The cAMP signaling system inhibits the repair of γ-ray-induced DNA damage by promoting Epac1-mediated proteasomal degradation of XRCC1 protein in human lung cancer cells

    International Nuclear Information System (INIS)

    Highlights: ► cAMP signaling system inhibits repair of γ-ray-induced DNA damage. ► cAMP signaling system inhibits DNA damage repair by decreasing XRCC1 expression. ► cAMP signaling system decreases XRCC1 expression by promoting its proteasomal degradation. ► The promotion of XRCC1 degradation by cAMP signaling system is mediated by Epac1. -- Abstract: Cyclic AMP is involved in the regulation of metabolism, gene expression, cellular growth and proliferation. Recently, the cAMP signaling system was found to modulate DNA-damaging agent-induced apoptosis by regulating the expression of Bcl-2 family proteins and inhibitors of apoptosis. Thus, we hypothesized that the cAMP signaling may modulate DNA repair activity, and we investigated the effects of the cAMP signaling system on γ-ray-induced DNA damage repair in lung cancer cells. Transient expression of a constitutively active mutant of stimulatory G protein (GαsQL) or treatment with forskolin, an adenylyl cyclase activator, augmented radiation-induced DNA damage and inhibited repair of the damage in H1299 lung cancer cells. Expression of GαsQL or treatment with forskolin or isoproterenol inhibited the radiation-induced expression of the XRCC1 protein, and exogenous expression of XRCC1 abolished the DNA repair-inhibiting effect of forskolin. Forskolin treatment promoted the ubiquitin and proteasome-dependent degradation of the XRCC1 protein, resulting in a significant decrease in the half-life of the protein after γ-ray irradiation. The effect of forskolin on XRCC1 expression was not inhibited by PKA inhibitor, but 8-pCPT-2′-O-Me-cAMP, an Epac-selective cAMP analog, increased ubiquitination of XRCC1 protein and decreased XRCC1 expression. Knockdown of Epac1 abolished the effect of 8-pCPT-2′-O-Me-cAMP and restored XRCC1 protein level following γ-ray irradiation. From these results, we conclude that the cAMP signaling system inhibits the repair of γ-ray-induced DNA damage by promoting the ubiquitin

  4. The cAMP signaling system inhibits the repair of {gamma}-ray-induced DNA damage by promoting Epac1-mediated proteasomal degradation of XRCC1 protein in human lung cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Eun-Ah [Department of Biochemistry and Molecular Biology, Cancer Research Center, Seoul National University College of Medicine, Seoul 110-799 (Korea, Republic of); Juhnn, Yong-Sung, E-mail: juhnn@snu.ac.kr [Department of Biochemistry and Molecular Biology, Cancer Research Center, Seoul National University College of Medicine, Seoul 110-799 (Korea, Republic of)

    2012-06-01

    Highlights: Black-Right-Pointing-Pointer cAMP signaling system inhibits repair of {gamma}-ray-induced DNA damage. Black-Right-Pointing-Pointer cAMP signaling system inhibits DNA damage repair by decreasing XRCC1 expression. Black-Right-Pointing-Pointer cAMP signaling system decreases XRCC1 expression by promoting its proteasomal degradation. Black-Right-Pointing-Pointer The promotion of XRCC1 degradation by cAMP signaling system is mediated by Epac1. -- Abstract: Cyclic AMP is involved in the regulation of metabolism, gene expression, cellular growth and proliferation. Recently, the cAMP signaling system was found to modulate DNA-damaging agent-induced apoptosis by regulating the expression of Bcl-2 family proteins and inhibitors of apoptosis. Thus, we hypothesized that the cAMP signaling may modulate DNA repair activity, and we investigated the effects of the cAMP signaling system on {gamma}-ray-induced DNA damage repair in lung cancer cells. Transient expression of a constitutively active mutant of stimulatory G protein (G{alpha}sQL) or treatment with forskolin, an adenylyl cyclase activator, augmented radiation-induced DNA damage and inhibited repair of the damage in H1299 lung cancer cells. Expression of G{alpha}sQL or treatment with forskolin or isoproterenol inhibited the radiation-induced expression of the XRCC1 protein, and exogenous expression of XRCC1 abolished the DNA repair-inhibiting effect of forskolin. Forskolin treatment promoted the ubiquitin and proteasome-dependent degradation of the XRCC1 protein, resulting in a significant decrease in the half-life of the protein after {gamma}-ray irradiation. The effect of forskolin on XRCC1 expression was not inhibited by PKA inhibitor, but 8-pCPT-2 Prime -O-Me-cAMP, an Epac-selective cAMP analog, increased ubiquitination of XRCC1 protein and decreased XRCC1 expression. Knockdown of Epac1 abolished the effect of 8-pCPT-2 Prime -O-Me-cAMP and restored XRCC1 protein level following {gamma}-ray irradiation. From

  5. WIN-34B May Have Analgesic and Anti-Inflammatory Effects by Reducing the Production of Pro-Inflammatory Mediators in Cells via Inhibition of IκB Signaling Pathways

    Science.gov (United States)

    Kim, Kyoung Soo; Choi, Hyun Mi; Yang, Hyung-In; Yoo, Myung Chul

    2012-01-01

    WIN-34B showed analgesic and anti-inflammatory effects in various animal models of pain and osteoarthritis. However, the molecular mechanism by which WIN-34B inhibits pain and inflammation in vivo remains to be elucidated. We investigated the molecular mechanisms of the actions of WIN-34B using various in vitro models using fibroblast-like synoviocytes from patients with rheumatoid arthritis (RA FLSs), RAW264.7 cells and peritoneal macrophages. WIN-34B inhibited the level of IL-6, PGE2, and MMP-13 in IL-1β-stimulated RA FLSs in a dose-dependent manner. The mRNA levels were also inhibited by WIN-34B. The level of PGE2, NO, IL-1β, and TNF-α were inhibited by WIN-34B at different concentrations in LPS-stimulated RAW264.7 cells. The production of NO and PGE2 was inhibited by WIN-34B in a dose-dependent manner in LPS-stimulated peritoneal macrophages. All of these effects were comparable to the positive control, celecoxib or indomethacin. IκB signaling pathways were inhibited by WIN-34B, and the migration of NF-κB into the nucleus was inhibited, which is consistent with the degradation of IκB-α. Taken together, the results suggest that WIN-34B has potential as a therapeutic drug to reduce pain and inflammation by inhibiting the production of pro-inflammatory mediators. PMID:24116274

  6. [6]-Gingerol induces caspase-dependent apoptosis and prevents PMA-induced proliferation in colon cancer cells by inhibiting MAPK/AP-1 signaling.

    Directory of Open Access Journals (Sweden)

    E K Radhakrishnan

    Full Text Available We report mechanism-based evidence for the anticancer and chemopreventive efficacy of [6]-gingerol, the major active principle of the medicinal plant, Ginger (Zingiber officinale, in colon cancer cells. The compound was evaluated in two human colon cancer cell lines for its cytotoxic effect and the most sensitive cell line, SW-480, was selected for the mechanistic evaluation of its anticancer and chemopreventive efficacy. The non-toxic nature of [6]-gingerol was confirmed by viability assays on rapidly dividing normal mouse colon cells. [6]-gingerol inhibited cell proliferation and induced apoptosis as evidenced by externalization of phosphatidyl serine in SW-480, while the normal colon cells were unaffected. Sensitivity to [6]-gingerol in SW-480 cells was associated with activation of caspases 8, 9, 3 &7 and cleavage of PARP, which attests induction of apoptotic cell death. Mechanistically, [6]-gingerol down-regulated Phorbol Myristate Acetate (PMA induced phosphorylation of ERK1/2 and JNK MAP kinases and activation of AP-1 transcription factor, but had only little effects on phosphorylation of p38 MAP kinase and activation of NF-kappa B. Additionally, it complemented the inhibitors of either ERK1/2 or JNK MAP kinase in bringing down the PMA-induced cell proliferation in SW-480 cells. We report the inhibition of ERK1/2/JNK/AP-1 pathway as a possible mechanism behind the anticancer as well as chemopreventive efficacy of [6]-gingerol against colon cancer.

  7. Pentoxifylline inhibits liver fibrosis via hedgehog signaling pathway.

    Science.gov (United States)

    Li, Hui; Hua, Juan; Guo, Chun-Xia; Wang, Wei-Xian; Wang, Bao-Ju; Yang, Dong-Liang; Wei, Ping; Lu, Yin-Ping

    2016-06-01

    Infection of schistosomiasis japonica may eventually lead to liver fibrosis, and no effective antifibrotic therapies are available but liver transplantation. Hedgehog (HH) signaling pathway has been involved in the process and is a promising target for treating liver fibrosis. This study aimed to explore the effects of pentoxifylline (PTX) on liver fibrosis induced by schistosoma japonicum infection by inhibiting the HH signaling pathway. Phorbol12-myristate13-acetate (PMA) was used to induce human acute mononuclear leukemia cells THP-1 to differentiate into macrophages. The THP-1-derived macrophages were stimulated by soluble egg antigen (SEA), and the culture supernatants were collected for detection of activation of macrophages. Cell Counting Kit-8 (CCK-8) was used to detect the cytotoxicity of the culture supernatant and PTX on the LX-2 cells. The LX-2 cells were administered with activated culture supernatant from macrophages and(or) PTX to detect the transforming growth factor-β gene expression. The mRNA expression of shh and gli-1, key parts in HH signaling pathway, was detected. The mRNA expression of shh and gli-1 was increased in LX-2 cells treated with activated macrophages-derived culture supernatant, suggesting HH signaling pathway may play a key role in the activation process of hepatic stellate cells (HSCs). The expression of these genes decreased in LX-2 cells co-cultured with both activated macrophages-derived culture supernatant and PTX, indicating PTX could suppress the activation process of HSCs. In conclusion, these data provide evidence that PTX prevents liver fibrogenesis in vitro by the suppression of HH signaling pathway. PMID:27376806

  8. IL-1β induces hypomyelination in the periventricular white matter through inhibition of oligodendrocyte progenitor cell maturation via FYN/MEK/ERK signaling pathway in septic neonatal rats.

    Science.gov (United States)

    Xie, Di; Shen, Fengcai; He, Shaoru; Chen, Mengmeng; Han, Qianpeng; Fang, Ming; Zeng, Hongke; Chen, Chunbo; Deng, Yiyu

    2016-04-01

    Neuroinflammation elicited by microglia plays a key role in periventricular white matter (PWM) damage (PWMD) induced by infectious exposure. This study aimed to determine if microglia-derived interleukin-1β (IL-1β) would induce hypomyelination through suppression of maturation of oligodendrocyte progenitor cells (OPCs) in the developing PWM. Sprague-Dawley rats (1-day old) were injected with lipopolysaccharide (LPS) (1 mg/kg) intraperitoneally, following which upregulated expression of IL-1β and IL-1 receptor 1 (IL-1R1 ) was observed. This was coupled with enhanced apoptosis and suppressed proliferation of OPCs in the PWM. The number of PDGFR-α and NG2-positive OPCs was significantly decreased in the PWM at 24 h and 3 days after injection of LPS, whereas it was increased at 14 days and 28 days. The protein expression of Olig1, Olig2, and Nkx2.2 was significantly reduced, and mRNA expression of Tcf4 and Axin2 was upregulated in the developing PWM after LPS injection. The expression of myelin basic protein (MBP) and 2',3'-cyclic-nucleotide 3"-phosphodiesterase (CNPase) was downregulated in the PWM at 14 days and 28 days after LPS injection; this was linked to reduction of the proportion of myelinated axons and thinner myelin sheath as revealed by electron microscopy. Primary cultured OPCs treated with IL-1β showed the failure of maturation and proliferation. Furthermore, FYN/MEK/ERK signaling pathway was involved in suppression of maturation of primary OPCs induced by IL-1β administration. Our results suggest that following LPS injection, microglia are activated and produce IL-1β in the PWM in the neonatal rats. Excess IL-1β inhibits the maturation of OPCs via suppression of FYN/MEK/ERK phosphorylation thereby leading to axonal hypomyelination.

  9. Inhibition of insulin-like growth factor-1 receptor signaling enhances growth-inhibitory and proapoptotic effects of gefitinib (Iressa) in human breast cancer cells

    OpenAIRE

    Camirand, Anne; Zakikhani, Mahvash; Young, Fiona; Pollak, Michael

    2005-01-01

    Introduction Gefitinib (Iressa, ZD 1839, AstraZeneca) blocks the tyrosine kinase activity of the epidermal growth factor receptor (EGFR) and inhibits proliferation of several human cancer cell types including breast cancer. Phase II clinical trials with gefitinib monotherapy showed an objective response of 9 to 19% in non-small-cell lung cancer patients and less than 10% for breast cancer, and phase III results have indicated no benefit of gefitinib in combination with chemotherapy over chemo...

  10. Hedyotis diffusa plus Scutellaria barbata Induce Bladder Cancer Cell Apoptosis by Inhibiting Akt Signaling Pathway through Downregulating miR-155 Expression

    OpenAIRE

    Li-Tao Pan; Yip Sheung; Wen-Peng Guo; Zhi-Bin Rong; Zhi-Ming Cai

    2016-01-01

    Traditional Chinese medicine is increasingly used to treat cancer. Our clinical experiences identify Hedyotis diffusa plus Scutellaria barbata as the most common herb-pair (couplet medicinal) used for the core treatment of bladder cancer. This study aims to investigate the antitumor effect of the herb-pair in bladder cancer cells. The results show that Hedyotis diffusa plus Scutellaria barbata inhibited bladder cancer cell growth and clone formation in a dose-dependent and time-dependent mann...

  11. Gardenia jasminoides extracts and gallic acid inhibit lipopolysaccharide-induced inflammation by suppression of JNK2/1 signaling pathways in BV-2 cells

    Directory of Open Access Journals (Sweden)

    Wen-Hung Lin

    2015-06-01

    Conclusion:Taken together, these results indicate that the protective mechanism of the GJ extract involves an antioxidant effect and inhibition of JNK2/1 MAP kinase and COX-2 expressions in LPS-induced inflammation of BV-2 cells.

  12. Zika Virus NS4A and NS4B Proteins Deregulate Akt-mTOR Signaling in Human Fetal Neural Stem Cells to Inhibit Neurogenesis and Induce Autophagy

    DEFF Research Database (Denmark)

    Liang, Qiming; Luo, Zhifei; Zeng, Jianxiong;

    2016-01-01

    development and autophagy regulation. Here, we show that ZIKV infection of human fetal neural stem cells (fNSCs) causes inhibition of the Akt-mTOR pathway, leading to defective neurogenesis and aberrant activation of autophagy. By screening the three structural proteins and seven nonstructural proteins...

  13. Helicobacter pylori Inhibits Dendritic Cell Maturation via Interleukin-10-Mediated Activation of the Signal Transducer and Activator of Transcription 3 Pathway.

    OpenAIRE

    Rizzuti, David; Ang, Michelle; Sokollik, Christiane; Wu, Ted; Abdullah, Majd; Greenfield, Laura; Fattouh, Ramzi; Reardon, Colin; Tang, Michael; Diao, Jun; Schindler, Christian; Cattral, Mark; Jones, Nicola L

    2014-01-01

    Helicobacter pylori infects the human gastric mucosa causing a chronic infection that is the primary risk factor for gastric cancer development. Recent studies demonstrate that H. pylori promotes tolerogenic dendritic cell (DC) development indicating that this bacterium evades the host immune response. However, the signaling pathways involved in modulating DC activation during infection remain unclear. Here, we report that H. pylori infection activated the signal transducer and activator of t...

  14. JAK2-V617F-mediated signalling is dependent on lipid rafts and statins inhibit JAK2-V617F-dependent cell growth

    OpenAIRE

    Griner, Lori N.; McGraw, Kathy L.; Johnson, Joseph O; List, Alan F.; Reuther, Gary W.

    2012-01-01

    Aberrant JAK2 signalling plays an important role in the aetiology of myeloproliferative neoplasms (MPNs). JAK2 inhibitors, however, do not readily eliminate neoplastic MPN cells and thus do not induce patient remission. Further understanding JAK2 signalling in MPNs may uncover novel avenues for therapeutic intervention. Recent work has suggested a potential role for cellular cholesterol in the activation of JAK2 by the erythropoietin receptor and in the development of an MPN-like disorder in ...

  15. Wogonin inhibits the proliferation and invasion, and induces the apoptosis of HepG2 and Bel7402 HCC cells through NF‑κB/Bcl-2, EGFR and EGFR downstream ERK/AKT signaling.

    Science.gov (United States)

    Liu, Xiaodong; Tian, Shuo; Liu, Mei; Jian, Lingyan; Zhao, Limei

    2016-10-01

    The anticancer effects of the natural flavonoid, wogonin, have been reported. However, its molecular mechanisms of action have not yet been fully explored. In the present study, we aimed to examine the molecular mechanisms of action of wogonin and its effects on the biological behavior of the HepG2 and Bel7402 hepatocellular carcinoma (HCC) cell lines. We also examined the effects of wogonin on nuclear factor-κB (NF-κB)/Bcl-2 and epidermal growth factor receptor (EGFR) signaling, as well as on downstream pathways of EGFR, namely extracellular signal-regulated kinase (ERK)/AKT signaling. We found that treatment with wogonin inhibited the proliferation and invasion, and induced the apoptosis of the HepG2 and Bel7402 cells. In addition, treatment with wogonin decreased cyclin D1, cyclin E, CDK4/6, Bcl-2 and matrix metalloproteinase 2 (MMP2) expression, and promoted the cleavage of caspase-3 and caspase-9 in a concentration-dependent manner. Further experiments revealed that wogonin inhibited NF-κB/Bcl-2 signaling by decreasing the IκB and p65 phosphorylation levels. Wogonin also inhibited the activation of the EGFR (Tyr845) signaling pathway, and that of downstream pathways of EGFR, namely ERK/AKT/MMP2 signaling. The depletion of EGFR by siRNA partly abolished the inhibitory effects of wogonin on cyclin D1, MMP2 expression. On the whole, our our findings demonstrate that wogonin effectively suppresses the proliferation, invasion and survival of HCC cells through the modulation of the NF-κB and EGFR signaling pathways.

  16. Curcumin inhibits Akt/mTOR signaling through protein phosphatase-dependent mechanism*

    OpenAIRE

    Yu, Siwang; Shen, Guoxiang; Khor, Tin Oo; Kim, Jung-Hwan; Kong, Ah-Ng

    2008-01-01

    Akt/mTOR signaling plays an important role in tumorigenesis and is dysregulated in many tumors, especially metastatic prostate cancers. Curcumin has been shown to effectively prevent or inhibit prostate cancer in vivo and inhibit Akt/mTOR signaling in vitro, but the mechanism(s) remains unclear. Here we show that curcumin concentration- and time-dependently inhibited the phosphorylation of Akt, mTOR, and their downstream substrates in human prostate cancer PC-3 cells, and this inhibitory effe...

  17. Mechanisms of early visual processing in the medulla of the locust optic lobe: how self-inhibition, spatial-pooling, and signal rectification contribute to the properties of transient cells.

    Science.gov (United States)

    Osorio, D

    1991-10-01

    In the arthropod medulla, which is the second ganglion on the afferent visual pathway, a column of about 40 cells represents each point in space (i.e. compound eye facet). Some stages of visual processing underlying the responses of one class of cells in the locust medulla have been identified. These transient cells give very similar responses to intensity increments and decrements, and also to pulses and steps; there is no spontaneous activity and a stimulus causes one or two spikes to fire at fixed latencies. Movement, however, produces a prolonged spike discharge by successive excitation of subunits within the receptive field. One of the main features of the transient cells' responses is a self-inhibition which attenuates responses to successive stimuli at one point. This inhibition is restricted to the outputs of single receptor (rhabdom), it decays after about 100 ms, and is polarity sensitive so that stimuli of one polarity (e.g. dimming) do not inhibit responses to stimuli of the opposite polarity (e.g. brightening). The inhibition effectively alters the contrast threshold of the cells, because after adaptation with stimuli of one contrast, a modest (less than 20%) increase in contrast is sufficient to elicit an unadapted response. Transient cells are not directionally selective and there are no local spatio-temporal interactions of the kind necessary for directional selectivity. But, by analogy with the directional veto in directionally selective cells in the rabbit retina (Barlow & Levick, 1965), self-inhibition is suggested as a mechanism of non-directional motion detection. After the inhibition, there is some spatial pooling of signals which is followed by rectification. The transient cells' spiking outputs could abstract a refined subset of visual information which may encode the presence, but not the direction, amplitude, or polarity of moving object borders.

  18. Regulation of MAPKs Signaling Contributes to the Growth Inhibition of 1,7-Dihydroxy-3,4-dimethoxyxanthone on Multidrug Resistance A549/Taxol Cells.

    Science.gov (United States)

    Zuo, Jian; Jiang, Hui; Zhu, Yan-Hong; Wang, Ya-Qin; Zhang, Wen; Luan, Jia-Jie

    2016-01-01

    1,7-Dihydroxy-3,4-dimethoxyxanthone (XAN) is a bioactive compound isolated from Securidaca inappendiculata Hassk. and validated with antiproliferative activities on a panel of cancer cell lines. This study was designed to investigate its growth inhibitory effects on multidrug resistance (MDR) non-small cell lung carcinoma (NSCLC) cell line A549/Taxol and explore the possible linkage between modulation of MAPKs and the bioactivities. Its growth inhibitory potency on the cells was estimated by MTT assay, and flow cytometric analysis was employed to investigate its potential cell cycle arrest and proapoptosis effects. Expressions of hallmark proteins were assessed by Western-Blot method. The results showed A549/Taxol cells were sensitive to XAN. XAN inhibited the proliferation of A549/Taxol cells in the time and concentration dependent manners. It acted as a potent inducer of apoptosis and cell cycle arrest in the cells. Western-Blot investigation validated the proapoptosis and cell cycle arrest activities of XAN and the potential of MDR reversion. Upregulation of p38 by XAN, which accounted for the cell cycle arrest at G2 phase, and the downregulation of ERK associated with the proapoptosis activity were also revealed. Further analysis found p53 may be the central role mediated the bioactivities of MAPKs in A549/Taxol cells. Based on these evidences, a conclusion has been deduced that XAN could be a potential agent for MDR NSCLC therapy targeting specifically MAPKs. PMID:27403196

  19. Regulation of MAPKs Signaling Contributes to the Growth Inhibition of 1,7-Dihydroxy-3,4-dimethoxyxanthone on Multidrug Resistance A549/Taxol Cells

    Directory of Open Access Journals (Sweden)

    Jian Zuo

    2016-01-01

    Full Text Available 1,7-Dihydroxy-3,4-dimethoxyxanthone (XAN is a bioactive compound isolated from Securidaca inappendiculata Hassk. and validated with antiproliferative activities on a panel of cancer cell lines. This study was designed to investigate its growth inhibitory effects on multidrug resistance (MDR non-small cell lung carcinoma (NSCLC cell line A549/Taxol and explore the possible linkage between modulation of MAPKs and the bioactivities. Its growth inhibitory potency on the cells was estimated by MTT assay, and flow cytometric analysis was employed to investigate its potential cell cycle arrest and proapoptosis effects. Expressions of hallmark proteins were assessed by Western-Blot method. The results showed A549/Taxol cells were sensitive to XAN. XAN inhibited the proliferation of A549/Taxol cells in the time and concentration dependent manners. It acted as a potent inducer of apoptosis and cell cycle arrest in the cells. Western-Blot investigation validated the proapoptosis and cell cycle arrest activities of XAN and the potential of MDR reversion. Upregulation of p38 by XAN, which accounted for the cell cycle arrest at G2 phase, and the downregulation of ERK associated with the proapoptosis activity were also revealed. Further analysis found p53 may be the central role mediated the bioactivities of MAPKs in A549/Taxol cells. Based on these evidences, a conclusion has been deduced that XAN could be a potential agent for MDR NSCLC therapy targeting specifically MAPKs.

  20. Lactobacillus amylovorus Inhibits the TLR4 Inflammatory Signaling Triggered by Enterotoxigenic Escherichia coli via Modulation of the Negative Regulators and Involvement of TLR2 in Intestinal Caco-2 Cells and Pig Explants

    Science.gov (United States)

    Finamore, Alberto; Roselli, Marianna; Imbinto, Ambra; Seeboth, Julie; Oswald, Isabelle P.; Mengheri, Elena

    2014-01-01

    Inflammation derived from pathogen infection involves the activation of toll-like receptor (TLR) signaling. Despite the established immunomodulatory activities of probiotics, studies relating the ability of such bacteria to inhibit the TLR signaling pathways are limited or controversial. In a previous study we showed that Lactobacillus amylovorus DSM 16698T, a novel lactobacillus isolated from unweaned pigs, protects the intestinal cells from enterotoxigenic Escherichia coli (ETEC) K88 infection through cytokine regulation. In the present study we investigated whether the ability of L. amylovorus to counteract the inflammatory status triggered by ETEC in intestine is elicited through inhibition of the TLR4 signaling pathway. We used the human intestinal Caco-2/TC7 cells and intestinal explants isolated from 5 week-old crossbreed Pietrain/Duroc/Large-White piglets, treated with ETEC, L. amylovorus or L. amylovorus cell free supernatant, either alone or simultaneously with ETEC. Western blot analysis showed that L. amylovorus and its cell free supernatant suppress the activation of the different steps of TLR4 signaling in Caco-2/TC7 cells and pig explants, by inhibiting the ETEC induced increase in the level of TLR4 and MyD88, the phosphorylation of the IKKα, IKKβ, IκBα and NF-κB subunit p65, as well as the over-production of inflammatory cytokines IL-8 and IL-1β. The immunofluorescence analysis confirms the lack of phospho-p65 translocation into the nucleus. These anti-inflammatory effects are achieved through modulation of the negative regulators Tollip and IRAK-M. We also found that L. amylovorus blocks the up-regulation of the extracellular heat shock protein (Hsp)72 and Hsp90, that are critical for TLR4 function. By using anti-TLR2 antibody, we demonstrate that TLR2 is required for the suppression of TLR4 signaling activation. These results may contribute to develop therapeutic interventions using L. amylovorus in intestinal disorders of piglets and humans

  1. Piperlongumine inhibits lung tumor growth via inhibition of nuclear factor kappa B signaling pathway.

    Science.gov (United States)

    Zheng, Jie; Son, Dong Ju; Gu, Sun Mi; Woo, Ju Rang; Ham, Young Wan; Lee, Hee Pom; Kim, Wun Jae; Jung, Jae Kyung; Hong, Jin Tae

    2016-01-01

    Piperlongumine has anti-cancer activity in numerous cancer cell lines via various signaling pathways. But there has been no study regarding the mechanisms of PL on the lung cancer yet. Thus, we evaluated the anti-cancer effects and possible mechanisms of PL on non-small cell lung cancer (NSCLC) cells in vivo and in vitro. Our findings showed that PL induced apoptotic cell death and suppressed the DNA binding activity of NF-κB in a concentration dependent manner (0-15 μM) in NSCLC cells. Docking model and pull down assay showed that PL directly binds to the DNA binding site of nuclear factor-κB (NF-κB) p50 subunit, and surface plasmon resonance (SPR) analysis showed that PL binds to p50 concentration-dependently. Moreover, co-treatment of PL with NF-κB inhibitor phenylarsine oxide (0.1 μM) or p50 siRNA (100 nM) augmented PL-induced inhibitory effect on cell growth and activation of Fas and DR4. Notably, co-treatment of PL with p50 mutant plasmid (C62S) partially abolished PL-induced cell growth inhibition and decreased the enhanced expression of Fas and DR4. In xenograft mice model, PL (2.5-5 mg/kg) suppressed tumor growth of NSCLC dose-dependently. Therefore, these results indicated that PL could inhibit lung cancer cell growth via inhibition of NF-κB signaling pathway in vitro and in vivo. PMID:27198178

  2. Matrine suppresses cell growth of human chronic myeloid leukemia cells via its inhibition of the interleukin-6/Janus activated kinase/signal transducer and activator of transcription 3 signaling cohort.

    Science.gov (United States)

    Ma, Lingdi; Zhu, Zhichao; Jiang, Lijia; Sun, Xiao; Lu, Xuzhang; Zhou, Min; Qian, Sixuan; Jianyong, Li

    2015-01-01

    Matrine, alkaloid isolated from Sophora flavescens, is known to be pleiotropic by exerting anti-inflammatory, anti-oxidation, as well as anti-cancer effects. However, the precise molecular targets or pathways responsible for its activities still remain unclear. The present study aimed to determine the underlying mechanisms of matrine in inhibiting the chronic myeloid leukemia cells (CML). It was observed that matrine treatment significantly suppressed CML cells proliferation, induced apoptosis and resulted in the accumulation of cells in the G0/G1 phase, accompanied by a significant decrease in Bcl-xL, Cyclin D1, and c-Myc expression. Western blot analyses revealed that matrine treatment resulted in the down-regulation in phospho-STAT3 and phospho-JAK2 without significantly effects on STAT3 and JAK2 protein levels. Matrine significantly reduced the expression of IL-6, a potent upstream activating factor of STAT3. These results strongly suggested the IL-6/JAK/STAT3 pathway play an important role in matrine's anti-leukemia effects in K562 cells.

  3. Inhibition of fatty acid synthase suppresses U-2 OS cell invasion and migration via downregulating the activity of HER2/PI3K/AKT signaling pathway in vitro

    International Nuclear Information System (INIS)

    Highlights: •We investigate the relationship between FASN and HER2 or p-HER2 by IHC in OS tissues. •We construct FASN-specific RNAi plasmid. •Inhibiting FASN down-regulates HER2/PI3K/AKT cell signaling in U-2 OS. •Inhibiting FASN blocks U-2 OS cell invasion and migration. -- Abstract: FASN plays an important role in the malignant phenotype of various tumors. Our previous studies show that inhibition FASN could induce apoptosis and inhibit proliferation in human osteosarcoma (OS) cell in vivo and vitro. The aim in this study was to investigate the effect of inhibition FASN on the activity of HER2/PI3K/AKT axis and invasion and migration of OS cell. The expression of FASN, HER2 and p-HER2(Y1248) proteins was detected by immunohistochemistry in OS tissues from 24 patients with pulmonary metastatic disease, and the relationship between FASN and p-HER2 as well as HER2 was investigated. The results showed that there was a positive correlation between FASN and HER2 as well as p-HER2 protein expression. The U-2 OS cells were transfected with either the FASN specific RNAi plasmid or the negative control RNAi plasmid. FASN mRNA was measured by RT-PCR. Western blot assays was performed to examine the protein expression of FASN, HER2, p-HER2(Y1248), PI3K, Akt and p-Akt (Ser473). Migration and invasion of cells were investigated by wound healing and transwell invasion assays. The results showed that the activity of HER2/PI3K/AKT signaling pathway was suppressed by inhibiting FASN. Meanwhile, the U-2OS cells migration and invasion were also impaired by inhibiting the activity of FASN/HER2/PI3K/AKT. Our results indicated that inhibition of FASN suppresses OS cell invasion and migration via down-regulation of the “HER2/PI3K/AKT” axis in vitro. FASN blocker may be a new therapeutic strategy in OS management

  4. β-Hydroxybutyric Sodium Salt Inhibition of Growth Hormone and Prolactin Secretion via the cAMP/PKA/CREB and AMPK Signaling Pathways in Dairy Cow Anterior Pituitary Cells

    OpenAIRE

    Shou-Peng Fu; Wei Wang(College of William and Mary); Bing-Run Liu; Huan-Min Yang; Hong Ji; Zhan-Qing Yang; Bin Guo; Ju-Xiong Liu; Jian-Fa Wang

    2015-01-01

    β-hydroxybutyric acid (BHBA) regulates the synthesis and secretion of growth hormone (GH) and prolactin (PRL), but its mechanism is unknown. In this study, we detected the effects of BHBA on the activities of G protein signaling pathways, AMPK-α activity, GH, and PRL gene transcription, and GH and PRL secretion in dairy cow anterior pituitary cells (DCAPCs). The results showed that BHBA decreased intracellular cAMP levels and a subsequent reduction in protein kinase A (PKA) activity. Inhibit...

  5. Carnosine Inhibits the Proliferation of Human Gastric Carcinoma Cells by Retarding Akt/mTOR/p70S6K Signaling

    OpenAIRE

    Zhang, Zhenwei; Miao, Lei; Wu, Xin; Liu, Guangze; Peng, Yuting; Xin, Xiaoming; Jiao, Binghua; Kong, Xiangping

    2014-01-01

    Carnosine (β-alanyl-L-histidine), described as an enigmatic peptide for its antioxidant, anti-aging and especially antiproliferation properties, has been demonstrated to play an anti-tumorigenic role in certain types of cancer. However, its function in human gastric carcinoma remains unclear. In this study, the effect of carnosine on cell proliferation and its underlying mechanisms were investigated in the cultured human gastric carcinoma cells. The mTOR signaling axis molecules were analyzed...

  6. Effect of Weifuchun of inhibiting inflammation of helicobacter pylori-infected GES-1 cells and NF-κB signaling pathway

    Institute of Scientific and Technical Information of China (English)

    黄宣

    2014-01-01

    Objective To study the effect of Weifuchun on inflammation of Helicobacter pylori(Hp)-infected gastric epithelial cells(GES-1)and its correlation with NF-κB signaling pathway.Methods Hp standard home-made strain(CagA+,VacA+)NCTCI 1637 infected GES-1cells were used.Weifuchun was used as intervention.Weifuchun of different concentrations(5,10,and 20μg/

  7. Exendin-4 Prevents Vascular Smooth Muscle Cell Proliferation and Migration by Angiotensin II via the Inhibition of ERK1/2 and JNK Signaling Pathways.

    Directory of Open Access Journals (Sweden)

    Kosuke Nagayama

    Full Text Available Angiotensin II (Ang II is a main pathophysiological culprit peptide for hypertension and atherosclerosis by causing vascular smooth muscle cell (VSMC proliferation and migration. Exendin-4, a glucagon-like peptide-1 (GLP-1 receptor agonist, is currently used for the treatment of type-2 diabetes, and is believed to have beneficial effects for cardiovascular diseases. However, the vascular protective mechanisms of GLP-1 receptor agonists remain largely unexplained. In the present study, we examined the effect of exendin-4 on Ang II-induced proliferation and migration of cultured rat aortic smooth muscle cells (RASMC. The major findings of the present study are as follows: (1 Ang II caused a phenotypic switch of RASMC from contractile type to synthetic proliferative type cells; (2 Ang II caused concentration-dependent RASMC proliferation, which was significantly inhibited by the pretreatment with exendin-4; (3 Ang II caused concentration-dependent RASMC migration, which was effectively inhibited by the pretreatment with exendin-4; (4 exendin-4 inhibited Ang II-induced phosphorylation of ERK1/2 and JNK in a pre-incubation time-dependent manner; and (5 U0126 (an ERK1/2 kinase inhibitor and SP600125 (a JNK inhibitor also inhibited both RASMC proliferation and migration induced by Ang II stimulation. These results suggest that exendin-4 prevented Ang II-induced VSMC proliferation and migration through the inhibition of ERK1/2 and JNK phosphorylation caused by Ang II stimulation. This indicates that GLP-1 receptor agonists should be considered for use in the treatment of cardiovascular diseases in addition to their current use in the treatment of diabetes mellitus.

  8. Plumbagin inhibits cell growth and potentiates apoptosis in human gastric cancer cells in vitro through the NF-κB signaling pathway

    OpenAIRE

    Li, Jing; Shen, Lin; Lu, Fu-rong; Qin, You; Chen, Rui; Li, Jia; Li, Yan; Zhan, Han-zi; He, Yuan-qiao

    2012-01-01

    Aim: To investigate the effects and underlying mechanisms of plumbagin, a naphthoquinone derived from medicinal plant Plumbago zeylanica, on human gastric cancer (GC) cells. Methods: Human gastric cancer cell lines SGC-7901, MKN-28, and AGS were used. The cell viability was examined using CCK-8 viability assay. Cell proliferation rate was determined using both clonogenic assay and EdU incorporation assay. Apoptosis was detected via Annexin V/propidium iodide double-labeled flow cytometry. Wes...

  9. Sargaquinoic Acid Inhibits TNF-α-Induced NF-κB Signaling, Thereby Contributing to Decreased Monocyte Adhesion to Human Umbilical Vein Endothelial Cells (HUVECs).

    Science.gov (United States)

    Gwon, Wi-Gyeong; Lee, Bonggi; Joung, Eun-Ji; Choi, Min-Woo; Yoon, Nayoung; Shin, Taisun; Oh, Chul-Woong; Kim, Hyeung-Rak

    2015-10-21

    Sargaquinoic acid (SQA) has been known for its antioxidant and anti-inflammatory properties. This study investigated the effects of SQA isolated from Sargassum serratifolium on the inhibition of tumor necrosis factor (TNF)-α-induced monocyte adhesion to human umbilical vein endothelial cells (HUVECs). SQA decreased the expression of cell adhesion molecules such as intracellular adhesion molecule-1 and vascular cell adhesion molecule-1 as well as chemotactic cytokines such as interleukin-8 and monocyte chemoattractant protein-1 in TNF-α-treated HUVECs. As a result, SQA prevented monocyte adhesion to TNF-α-induced adhesion. SQA also inhibited TNF-α-induced nuclear factor kappa B (NF-κB) translocation into the nucleus by preventing proteolytic degradation of inhibitor κB-α. Overall, SQA protects against TNF-α-induced vascular inflammation through inhibition of the NF-κB pathway in HUVECs. These data suggest that SQA may be used as a therapeutic agent for vascular inflammatory diseases such as atherosclerosis. PMID:26437568

  10. Dual Inhibition of Activin/Nodal/TGF-β and BMP Signaling Pathways by SB431542 and Dorsomorphin Induces Neuronal Differentiation of Human Adipose Derived Stem Cells

    Directory of Open Access Journals (Sweden)

    Vedavathi Madhu

    2016-01-01

    Full Text Available Damage to the nervous system can cause devastating diseases or musculoskeletal dysfunctions and transplantation of progenitor stem cells can be an excellent treatment option in this regard. Preclinical studies demonstrate that untreated stem cells, unlike stem cells activated to differentiate into neuronal lineage, do not survive in the neuronal tissues. Conventional methods of inducing neuronal differentiation of stem cells are complex and expensive. We therefore sought to determine if a simple, one-step, and cost effective method, previously reported to induce neuronal differentiation of embryonic stem cells and induced-pluripotent stem cells, can be applied to adult stem cells. Indeed, dual inhibition of activin/nodal/TGF-β and BMP pathways using SB431542 and dorsomorphin, respectively, induced neuronal differentiation of human adipose derived stem cells (hADSCs as evidenced by formation of neurite extensions, protein expression of neuron-specific gamma enolase, and mRNA expression of neuron-specific transcription factors Sox1 and Pax6 and matured neuronal marker NF200. This process correlated with enhanced phosphorylation of p38, Erk1/2, PI3K, and Akt1/3. Additionally, in vitro subcutaneous implants of SB431542 and dorsomorphin treated hADSCs displayed significantly higher expression of active-axonal-growth-specific marker GAP43. Our data offers novel insights into cell-based therapies for the nervous system repair.

  11. Metformin inhibits 7,12-dimethylbenz[a]anthracene-induced breast carcinogenesis and adduct formation in human breast cells by inhibiting the cytochrome P4501A1/aryl hydrocarbon receptor signaling pathway

    International Nuclear Information System (INIS)

    Recent studies have established that metformin (MET), an oral anti-diabetic drug, possesses antioxidant activity and is effective against different types of cancer in several carcinogen-induced animal models and cell lines. However, whether MET can protect against breast cancer has not been reported before. Therefore, the overall objectives of the present study are to elucidate the potential chemopreventive effect of MET in non-cancerous human breast MCF10A cells and explore the underlying mechanism involved, specifically the role of cytochrome P4501A1 (CYP1A1)/aryl hydrocarbon receptor (AhR) pathway. Transformation of the MCF10A cells into initiated breast cancer cells with DNA adduct formation was conducted using 7,12-dimethylbenz[a]anthracene (DMBA), an AhR ligand. The chemopreventive effect of MET against DMBA-induced breast carcinogenesis was evidenced by the capability of MET to restore the induction of the mRNA levels of basic excision repair genes, 8-oxoguanine DNA glycosylase (OGG1) and apurinic/apyrimidinic endonuclease1 (APE1), and the level of 8-hydroxy-2-deoxyguanosine (8-OHdG). Interestingly, the inhibition of DMBA-induced DNA adduct formation was associated with proportional decrease in CYP1A1 and in NAD(P)H:quinone oxidoreductase 1 (NQO1) gene expression. Mechanistically, the involvements of AhR and nuclear factor erythroid 2-related factor-2 (Nrf2) in the MET-mediated inhibition of DMBA-induced CYP1A1 and NQO1 gene expression were evidenced by the ability of MET to inhibit DMBA-induced xenobiotic responsive element and antioxidant responsive element luciferase reporter gene expression which suggests an AhR- and Nrf2-dependent transcriptional control. However, the inability of MET to bind to AhR suggests that MET is not an AhR ligand. In conclusion, the present work shows a strong evidence that MET inhibits the DMBA-mediated carcinogenicity and adduct formation by inhibiting the expression of CYP1A1 through an AhR ligand-independent mechanism

  12. Metformin inhibits 7,12-dimethylbenz[a]anthracene-induced breast carcinogenesis and adduct formation in human breast cells by inhibiting the cytochrome P4501A1/aryl hydrocarbon receptor signaling pathway

    Energy Technology Data Exchange (ETDEWEB)

    Maayah, Zaid H. [Department of Pharmacology and Toxicology, College of Pharmacy, King Saud University, Riyadh 11451 (Saudi Arabia); Ghebeh, Hazem [Stem Cell & Tissue Re-Engineering, King Faisal Specialist Hospital and Research Center, Riyadh 11211 (Saudi Arabia); Alhaider, Abdulqader A. [Department of Pharmacology and Toxicology, College of Pharmacy, King Saud University, Riyadh 11451 (Saudi Arabia); Camel Biomedical Research Unit, College of Pharmacy and Medicine, King Saud University, Riyadh 11451 (Saudi Arabia); El-Kadi, Ayman O.S. [Faculty of Pharmacy & Pharmaceutical Sciences, University of Alberta, Edmonton (Canada); Soshilov, Anatoly A.; Denison, Michael S. [Department of Environmental Toxicology, University of California at Davis, Davis, CA 95616 (United States); Ansari, Mushtaq Ahmad [Department of Pharmacology and Toxicology, College of Pharmacy, King Saud University, Riyadh 11451 (Saudi Arabia); Korashy, Hesham M., E-mail: hkorashy@ksu.edu.sa [Department of Pharmacology and Toxicology, College of Pharmacy, King Saud University, Riyadh 11451 (Saudi Arabia)

    2015-04-15

    Recent studies have established that metformin (MET), an oral anti-diabetic drug, possesses antioxidant activity and is effective against different types of cancer in several carcinogen-induced animal models and cell lines. However, whether MET can protect against breast cancer has not been reported before. Therefore, the overall objectives of the present study are to elucidate the potential chemopreventive effect of MET in non-cancerous human breast MCF10A cells and explore the underlying mechanism involved, specifically the role of cytochrome P4501A1 (CYP1A1)/aryl hydrocarbon receptor (AhR) pathway. Transformation of the MCF10A cells into initiated breast cancer cells with DNA adduct formation was conducted using 7,12-dimethylbenz[a]anthracene (DMBA), an AhR ligand. The chemopreventive effect of MET against DMBA-induced breast carcinogenesis was evidenced by the capability of MET to restore the induction of the mRNA levels of basic excision repair genes, 8-oxoguanine DNA glycosylase (OGG1) and apurinic/apyrimidinic endonuclease1 (APE1), and the level of 8-hydroxy-2-deoxyguanosine (8-OHdG). Interestingly, the inhibition of DMBA-induced DNA adduct formation was associated with proportional decrease in CYP1A1 and in NAD(P)H:quinone oxidoreductase 1 (NQO1) gene expression. Mechanistically, the involvements of AhR and nuclear factor erythroid 2-related factor-2 (Nrf2) in the MET-mediated inhibition of DMBA-induced CYP1A1 and NQO1 gene expression were evidenced by the ability of MET to inhibit DMBA-induced xenobiotic responsive element and antioxidant responsive element luciferase reporter gene expression which suggests an AhR- and Nrf2-dependent transcriptional control. However, the inability of MET to bind to AhR suggests that MET is not an AhR ligand. In conclusion, the present work shows a strong evidence that MET inhibits the DMBA-mediated carcinogenicity and adduct formation by inhibiting the expression of CYP1A1 through an AhR ligand-independent mechanism

  13. Differential Inhibition of the TGF-β Signaling Pathway in HCC Cells Using the Small Molecule Inhibitor LY2157299 and the D10 Monoclonal Antibody against TGF-β Receptor Type II.

    Directory of Open Access Journals (Sweden)

    Francesco Dituri

    Full Text Available We investigated blocking the TGF-β signaling pathway in HCC using two small molecule inhibitors (LY2157299, LY2109761 and a neutralizing humanized antibody (D10 against TGF-βRII. LY2157299 and LY2109761 inhibited HCC cell migration on Laminin-5, Fibronectin, Vitronectin, Fibrinogen and Collagen-I and de novo phosphorylation of pSMAD2. LY2157299 inhibited HCC migration and cell growth independently of the expression levels of TGF-βRII. In contrast to LY2157299, D10 showed a reduction in pSMAD2 only after a short exposure. This study supports the use of LY2157299 in clinical trials, and presents new insights into TGF-β receptor cycling in cancer cells.

  14. Flavokawain C Inhibits Cell Cycle and Promotes Apoptosis, Associated with Endoplasmic Reticulum Stress and Regulation of MAPKs and Akt Signaling Pathways in HCT 116 Human Colon Carcinoma Cells.

    Directory of Open Access Journals (Sweden)

    Chung-Weng Phang

    Full Text Available Flavokawain C (FKC is a naturally occurring chalcone which can be found in Kava (Piper methysticum Forst root. The present study evaluated the effect of FKC on the growth of various human cancer cell lines and the underlying associated mechanisms. FKC showed higher cytotoxic activity against HCT 116 cells in a time- and dose-dependent manner in comparison to other cell lines (MCF-7, HT-29, A549 and CaSki, with minimal toxicity on normal human colon cells. The apoptosis-inducing capability of FKC on HCT 116 cells was evidenced by cell shrinkage, chromatin condensation, DNA fragmentation and increased phosphatidylserine externalization. FKC was found to disrupt mitochondrial membrane potential, resulting in the release of Smac/DIABLO, AIF and cytochrome c into the cytoplasm. Our results also revealed that FKC induced intrinsic and extrinsic apoptosis via upregulation of the levels of pro-apoptotic proteins (Bak and death receptors (DR5, while downregulation of the levels of anti-apoptotic proteins (XIAP, cIAP-1, c-FlipL, Bcl-xL and survivin, resulting in the activation of caspase-3, -8 and -9 and cleavage of poly(ADP-ribose polymerase (PARP. FKC was also found to cause endoplasmic reticulum (ER stress, as suggested by the elevation of GADD153 protein after FKC treatment. After the cells were exposed to FKC (60μM over 18hrs, there was a substantial increase in the phosphorylation of ERK 1/2. The expression of phosphorylated Akt was also reduced. FKC also caused cell cycle arrest in the S phase in HCT 116 cells in a time- and dose-dependent manner and with accumulation of cells in the sub-G1 phase. This was accompanied by the downregulation of cyclin-dependent kinases (CDK2 and CDK4, consistent with the upregulation of CDK inhibitors (p21Cip1 and p27Kip1, and hypophosphorylation of Rb.

  15. 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.

  16. Hedyotis diffusa plus Scutellaria barbata Induce Bladder Cancer Cell Apoptosis by Inhibiting Akt Signaling Pathway through Downregulating miR-155 Expression.

    Science.gov (United States)

    Pan, Li-Tao; Sheung, Yip; Guo, Wen-Peng; Rong, Zhi-Bin; Cai, Zhi-Ming

    2016-01-01

    Traditional Chinese medicine is increasingly used to treat cancer. Our clinical experiences identify Hedyotis diffusa plus Scutellaria barbata as the most common herb-pair (couplet medicinal) used for the core treatment of bladder cancer. This study aims to investigate the antitumor effect of the herb-pair in bladder cancer cells. The results show that Hedyotis diffusa plus Scutellaria barbata inhibited bladder cancer cell growth and clone formation in a dose-dependent and time-dependent manner. It also induced cell apoptosis through decreasing Akt activation and reducing the expression of antiapoptotic proteins Bcl-2 and Mcl-1. Further experiments showed that miR-155 was reduced by the herb-pair and miRNA-155 inhibitor induced cell apoptosis and suppressed Akt activation. Overexpression of miR-155 reversed herb-pair induced cell apoptosis through activating Akt pathway in both bladder cancer cell lines. The findings reveal that Hedyotis diffusa plus Scutellaria barbata reduce Akt activation through reducing miR-155 expression, resulting in cell apoptosis. It demonstrated the potential mechanism of Hedyotis diffusa plus Scutellaria barbata for the core treatment of bladder cancer. PMID:26989427

  17. Hedyotis diffusa plus Scutellaria barbata Induce Bladder Cancer Cell Apoptosis by Inhibiting Akt Signaling Pathway through Downregulating miR-155 Expression

    Directory of Open Access Journals (Sweden)

    Li-Tao Pan

    2016-01-01

    Full Text Available Traditional Chinese medicine is increasingly used to treat cancer. Our clinical experiences identify Hedyotis diffusa plus Scutellaria barbata as the most common herb-pair (couplet medicinal used for the core treatment of bladder cancer. This study aims to investigate the antitumor effect of the herb-pair in bladder cancer cells. The results show that Hedyotis diffusa plus Scutellaria barbata inhibited bladder cancer cell growth and clone formation in a dose-dependent and time-dependent manner. It also induced cell apoptosis through decreasing Akt activation and reducing the expression of antiapoptotic proteins Bcl-2 and Mcl-1. Further experiments showed that miR-155 was reduced by the herb-pair and miRNA-155 inhibitor induced cell apoptosis and suppressed Akt activation. Overexpression of miR-155 reversed herb-pair induced cell apoptosis through activating Akt pathway in both bladder cancer cell lines. The findings reveal that Hedyotis diffusa plus Scutellaria barbata reduce Akt activation through reducing miR-155 expression, resulting in cell apoptosis. It demonstrated the potential mechanism of Hedyotis diffusa plus Scutellaria barbata for the core treatment of bladder cancer.

  18. Piperlongumine, an alkaloid causes inhibition of PI3 K/Akt/mTOR signaling axis to induce caspase-dependent apoptosis in human triple-negative breast cancer cells.

    Science.gov (United States)

    Shrivastava, Shweta; Kulkarni, Prasad; Thummuri, Dinesh; Jeengar, Manish Kumar; Naidu, V G M; Alvala, Mallika; Redddy, G Bhanuprakash; Ramakrishna, Sistla

    2014-07-01

    The phosphatidylinositol 3-kinase (PI3 K)/Akt/mammalian target of rapamycin (mTOR) signaling axis plays a central role in cell proliferation, growth and survival under physiological conditions. However, aberrant PI3 K/Akt/mTOR signaling has been implicated in many human cancers, including human triple negative breast cancer. Therefore, dual inhibitors of PI3 K/Akt and mTOR signaling could be valuable agents for treating breast cancer. The objective of this study was to investigate the effect of piperlongumine (PPLGM), a natural alkaloid on PI3 K/Akt/mTOR signaling, Akt mediated regulation of NF-kB and apoptosis evasion in human breast cancer cells. Using molecular docking studies, we found that PPLGM physically interacts with the conserved domain of PI3 K and mTOR kinases and the results were comparable with standard dual inhibitor PF04691502. Our results demonstrated that treatment of different human triple-negative breast cancer cells with PPLGM resulted in concentration- and time-dependent growth inhibition. The inhibition of cancer cell growth was associated with G1-phase cell cycle arrest and down-regulation of the NF-kB pathway leads to activation of the mitochondrial apoptotic pathway. It was also found that PPLGM significantly decreased the expression of p-Akt, p70S6K1, 4E-BP1, cyclin D1, Bcl-2, p53 and increased expression of Bax, cytochrome c in human triple-negative breast cancer cells. Although insulin treatment increased the phosphorylation of Akt (Ser473), p70S6K1, 4E-BP1, PPLGM abolished the insulin mediated phosphorylation, it clearly indicates that PPLGM acts through PI3 k/Akt/mTOR axis. Our results suggest that PPLGM may be an effective therapeutic agent for the treatment of human triple negative breast cancer. PMID:24729100

  19. 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...

  20. Luteolin 8-C-β-fucopyranoside inhibits invasion and suppresses TPA-induced MMP-9 and IL-8 via ERK/AP-1 and ERK/NF-κB signaling in MCF-7 breast cancer cells.

    Science.gov (United States)

    Park, Su-Ho; Kim, Jung-Hee; Lee, Dong-Hun; Kang, Jeong-Woo; Song, Hyuk-Hwan; Oh, Sei-Ryang; Yoon, Do-Young

    2013-11-01

    Matrix metalloproteinase 9 (MMP-9) and interleukin-8 (IL-8) play major roles in tumor progression and invasion of breast cancer cells. The present study was undertaken to investigate the inhibitory mechanism of cell invasion by luteolin 8-C-β-fucopyranoside (named as LU8C-FP), a C-glycosylflavone, in human breast cancer cells. We investigated whether LU8C-FP would inhibit MMP-9 activation and IL-8 expression in 12-O-tetradecanoylphorbol-13-acetate (TPA)-treated MCF-7 breast cancer cells. LU8C-FP suppressed TPA-induced MMP-9 and IL-8 secretion and mRNA expression via inhibition of the MAPK signaling pathway and down-regulation of nuclear AP-1 and NF-κB. TPA-induced phosphorylation of ERK 1/2 was suppressed by LU8C-FP, whereas JNK and p38 MAPK phosphorylation were unaffected. In addition, LU8C-FP blocked the ERK 1/2 pathways following expression of MMP-9 and IL-8. These results suggest LU8C-FP may function to suppress invasion of breast cancer cells through the ERK/AP-1 and ERK/NF-κB signaling cascades.

  1. Naringin suppresses cell metastasis and the expression of matrix metalloproteinases (MMP-2 and MMP-9) via the inhibition of ERK-P38-JNK signaling pathway in human glioblastoma.

    Science.gov (United States)

    Aroui, Sonia; Aouey, Bakhta; Chtourou, Yassine; Meunier, Annie-Claire; Fetoui, Hamadi; Kenani, Abderraouf

    2016-01-25

    Naringin (4',5,7-trihydroxyflavanone 7-rhamnoglucoside), a natural flavonoid, has pharmacological properties. In the present study, we investigated the anti-metastatic activity of naringin and its molecular mechanism(s) of action in human glioblastoma cells. Naringin exhibits inhibitory effects on the invasion and adhesion of U87 cells in a concentration-dependent manner by Matrigel Transwell and cell adhesion assays. Naringin also inhibited the migration of U87 cells in a concentration-dependent manner by wound-healing assay. Additional experiments showed that naringin treatment reduced the enzymatic activities and protein levels of matrix metalloproteinase (MMP)-2 and MMP-9 using a gelatin zymography assay and western blot analyses. Furthermore, naringin was able to reduce the protein phosphorylation of extracellular signal-regulated kinase ERK, p38 mitogen-activated protein kinase and c-Jun N-terminal kinase by western blotting. Collectively, our data showed that naringin attenuated the MAPK signaling pathways including ERK, JNK and p38 and resulted in the downregulation of the expression and enzymatic activities of MMP-2, MMP-9, contributing to the inhibition of metastasis in U87 cells. These findings proved that naringin may offer further application as an antimetastatic agent. PMID:26721195

  2. XAV939, a tankyrase 1 inhibitior, promotes cell apoptosis in neuroblastoma cell lines by inhibiting Wnt/β-catenin signaling pathway

    OpenAIRE

    Tian, Xiao-Hong; Hou, Wei-Jian; Fang, Yan; Fan, Jun; Tong, Hao; Bai, Shu-Ling; Chen, Qu; Xu, He; Li, Yan

    2013-01-01

    Background Neuroblastoma (NB) is the most common extracranial solid tumor in childhood. The present treatment including surgery, chemotherapy and radiation, which have only 40% long-term cure rates, and usually cause tumor recurrence. Thus, looking for new effective and less toxic therapies has important significance. XAV939 is a small molecule inhibitor of tankyrase 1(TNKS1). The objective of this study is to investigate the effect of XAV939 on the proliferation and apoptosis of NB cell line...

  3. NS5ATP9 Contributes to Inhibition of Cell Proliferation by Hepatitis C Virus (HCV Nonstructural Protein 5A (NS5A via MEK/Extracellular Signal Regulated Kinase (ERK Pathway

    Directory of Open Access Journals (Sweden)

    Xuesong Gao

    2013-05-01

    Full Text Available Hepatitis C virus (HCV nonstructural protein 5A (NS5A is a remarkable protein as it clearly plays multiple roles in mediating viral replication, host-cell interactions and viral pathogenesis. However, on the impact of cell growth, there have been different study results. NS5ATP9, also known as KIAA0101, p15PAF, L5, and OEACT-1, was first identified as a proliferating cell nuclear antigen-binding protein. Earlier studies have shown that NS5ATP9 might play an important role in HCV infection. The aim of this study is to investigate the function of NS5ATP9 on hepatocellular carcinoma (HCC cell lines proliferation under HCV NS5A expression. The results showed that overexpression of NS5ATP9 inhibited the proliferation of Bel7402 cells, whereas knockdown of NS5ATP9 by interfering RNA promoted the growth of HepG2 cells. Under HCV NS5A expression, RNA interference (RNAi targeting of NS5ATP9 could reverse the inhibition of HepG2 cell proliferation, suggesting that NS5ATP9 might be an anti-proliferation gene that plays an important role in the suppression of cell growth mediated by HCV NS5A via MEK/ERK signaling pathway. These findings might provide new insights into HCV NS5A and NS5ATP9.

  4. β-Adrenergic receptor antagonists inhibit vasculogenesis of embryonic stem cells by downregulation of nitric oxide generation and interference with VEGF signalling.

    Science.gov (United States)

    Sharifpanah, Fatemeh; Saliu, Fatjon; Bekhite, Mohamed M; Wartenberg, Maria; Sauer, Heinrich

    2014-11-01

    The β-adrenoceptor antagonist Propranolol has been successfully used to treat infantile hemangioma. However, its mechanism of action is so far unknown. The hypothesis of this research was that β-adrenoceptor antagonists may interfere with endothelial cell differentiation of stem cells. Specifically, the effects of the non-specific β-adrenergic receptor (β-adrenoceptor) antagonist Propranolol, the β1-adrenoceptor-specific antagonist Atenolol and the β2-adrenoceptor-specific antagonist ICI118,551 on vasculogenesis of mouse embryonic stem (ES) cells were investigated. All three β-blockers dose-dependently downregulated formation of capillary structures in ES cell-derived embryoid bodies and decreased the expression of the vascular cell markers CD31 and VE-cadherin. Furthermore, β-blockers downregulated the expression of fibroblast growth factor-2 (FGF-2), hypoxia inducible factor-1α (HIF-1α), vascular endothelial growth factor 165 (VEGF165), VEGF receptor 2 (VEGF-R2) and phospho VEGF-R2, as well as neuropilin 1 (NRP1) and plexin-B1 which are essential modulators of embryonic angiogenesis with additional roles in vessel remodelling and arteriogenesis. Under conditions of β-adrenoceptor inhibition, the endogenous generation of nitric oxide (NO) as well as the phosphorylation of endothelial nitric oxide synthase (eNOS) was decreased in embryoid bodies, whereas an increase in NO generation was observed with the NO donor S-nitroso-N-acetyl-D,L-penicillamine (SNAP). Consequently, vasculogenesis of ES cells was restored upon treatment of differentiating ES cells with β-adrenoceptor antagonists in the presence of NO donor. In summary, our data suggest that β-blockers impair vasculogenesis of ES cells by interfering with NO generation which could be the explanation for their anti-angiogenic effects in infantile hemangioma.

  5. Tumor shrinkage by cyclopamine tartrate through inhibiting hedgehog signaling

    Institute of Scientific and Technical Information of China (English)

    Qipeng Fan; Arash Garrossian; Massoud Garrossian; Dale Gardner; Jingwu Xie; Dongsheng Gu; Miao He; Hailan Liu; Tao Sheng; Guorui Xie; Ching-xin Li; Xiaoli Zhang; Brandon Wainwright

    2011-01-01

    The link of hedgehog (Hh) signaling activation to human cancer and synthesis of a variety of Hh signaling inhibitors raise great expectation that inhibiting Hh signaling may be effective in human cancer treatment. Cyclopamine (Cyc), an alkaloid from the Veratrum plant, is a specific natural product inhibitor of the Hh pathway that acts by targeting smoothened (SMO) protein. However, its poor solubility, acid sensitivity, and weak potency relative to other Hh antagonists prevent the clinical development of Cyc as a therapeutic agent. Here, we report properties of cyclopamine tartrate salt (CycT) and its activities in Hh signaling-mediated cancer in vitro and in vivo. Unlike Cyc, CycT is water soluble (5-10 mg/mL). The median lethal dose (LD) of CycT was 62.5 mg/kg body weight compared to 43.5 mg/kg for Cyc, and the plasma half-life (T) of CycT was not significantly different from that of Cyc. We showed that CycT had a higher inhibitory activity for Hh signaling-dependent motor neuron differentiation than did Cyc (IC = 50nmol/L for CycT vs. 300 nmol/L for Cyc). We also tested the antitumor effectiveness of these Hh inhibitors using two mouse models of basal cell carcinomas (K14cre:Ptch1and K14cre:SmoM2). After topical application of CycT or Cyc daily for 21 days, we found that all CycT-treated mice had tumor shrinkage and decreased expression of Hh target genes. Taken together, we found that CycT is an effective inhibitor of Hh signaling-mediated carcinogenesis.

  6. 1,25(OH)2D3 and VDR Signaling Pathways Regulate the Inhibition of Dectin-1 Caused by Cyclosporine A in Response to Aspergillus Fumigatus in Human Corneal Epithelial Cells

    Science.gov (United States)

    Xia, Yiping; Zhao, Guiqiu; Lin, Jing; Li, Cui; Cong, Lin; Jiang, Nan; Xu, Qiang; Wang, Qian

    2016-01-01

    Background The objective of this study is to observe whether cyclosporine A (CsA) inhibits the expression of dectin-1 in human corneal epithelial cells infected with Aspergillus fumigatus (A. fumigatus) and to investigate the molecular mechanisms of the inhibition. Methods Immortalized human corneal epithelial cells (HCECs) were pretreated with 1,25(OH)2D3 and VDR inhibitor for 1 h, and then they were pretreated with CsA for 12h. After these pretreatments, the HCECs were stimulated with A. fumigatus and curdlan respectively, and the expression of dectin-1 and proinflammatory cytokines (IL-1β and TNF-α) were detected by RT-PCR, western blot and ELISA. Results Dectin-1 mRNA and dectin-1 protein expression increased when HCECs were stimulated with A. fumigatus or curdlan, and CsA inhibited the dectin-1 expression both in mRNA and protein levels specifically. Dectin-1 and proinflammatory cytokine expression levels were higher when HCECs were pretreated with VDR inhibitor and CsA compared to pretreatment with CsA alone, while dectin-1 and proinflammatory cytokine levels were lower when HCECs were pretreated with 1,25(OH)2D3 and CsA compared to pretreatment with CsA alone. Conclusions These data provide evidence that CsA can inhibit the expression of dectin-1 and proinflammatory cytokines through dectin-1 when HCECs are stimulated by A. fumigatus or curdlan. The active form of vitamin D, 1,25(OH)2D3, and VDR signaling pathway regulate the inhibition of CsA. The inhibition is enhanced by 1,25(OH)2D3, and the VDR inhibitor suppresses the inhibition. PMID:27755569

  7. Inhibition of the PI3K/Akt/mTOR Signaling Pathway in Diffuse Large B-Cell Lymphoma: Current Knowledge and Clinical Significance

    Directory of Open Access Journals (Sweden)

    Agata Majchrzak

    2014-09-01

    Full Text Available Diffuse large B-cell lymphoma (DLBCL is one of the most common non-Hodgkin lymphomas in adults. The disease is very heterogeneous in its presentation, that is DLBCL patients may differ from each other not only in regard to histology of tissue infiltration, clinical course or response to treatment, but also in respect to diversity in gene expression profiling. A growing body of knowledge on the biology of DLBCL, including abnormalities in intracellular signaling, has allowed the development of new treatment strategies, specifically directed against lymphoma cells. The phosphoinositide 3-kinase (PI3K/protein kinase B (Akt/mammalian target of rapamycin (mTOR signaling pathway plays an important role in controlling proliferation and survival of tumor cells in various types of malignancies, including DLBCL, and therefore it may be a promising target for therapeutic intervention. Currently, novel anticancer drugs are undergoing assessment in different phases of clinical trials in aggressive lymphomas, with promising outcomes. In this review we present a state of art review on various classes of small molecule inhibitors selectively involving PI3K/Akt/mTOR pathway and their clinical potential in this disease.

  8. Inhibition of the PI3K/Akt/mTOR signaling pathway in diffuse large B-cell lymphoma: current knowledge and clinical significance.

    Science.gov (United States)

    Majchrzak, Agata; Witkowska, Magdalena; Smolewski, Piotr

    2014-09-11

    Diffuse large B-cell lymphoma (DLBCL) is one of the most common non-Hodgkin lymphomas in adults. The disease is very heterogeneous in its presentation, that is DLBCL patients may differ from each other not only in regard to histology of tissue infiltration, clinical course or response to treatment, but also in respect to diversity in gene expression profiling. A growing body of knowledge on the biology of DLBCL, including abnormalities in intracellular signaling, has allowed the development of new treatment strategies, specifically directed against lymphoma cells. The phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt)/mammalian target of rapamycin (mTOR) signaling pathway plays an important role in controlling proliferation and survival of tumor cells in various types of malignancies, including DLBCL, and therefore it may be a promising target for therapeutic intervention. Currently, novel anticancer drugs are undergoing assessment in different phases of clinical trials in aggressive lymphomas, with promising outcomes. In this review we present a state of art review on various classes of small molecule inhibitors selectively involving PI3K/Akt/mTOR pathway and their clinical potential in this disease.

  9. Inhibition of caspases prevents ototoxic and ongoing hair cell death

    Science.gov (United States)

    Matsui, Jonathan I.; Ogilvie, Judith M.; Warchol, Mark E.

    2002-01-01

    Sensory hair cells die after acoustic trauma or ototoxic insults, but the signal transduction pathways that mediate hair cell death are not known. Here we identify several important signaling events that regulate the death of vestibular hair cells. Chick utricles were cultured in media supplemented with the ototoxic antibiotic neomycin and selected pharmacological agents that influence signaling molecules in cell death pathways. Hair cells that were treated with neomycin exhibited classically defined apoptotic morphologies such as condensed nuclei and fragmented DNA. Inhibition of protein synthesis (via treatment with cycloheximide) increased hair cell survival after treatment with neomycin, suggesting that hair cell death requires de novo protein synthesis. Finally, the inhibition of caspases promoted hair cell survival after neomycin treatment. Sensory hair cells in avian vestibular organs also undergo continual cell death and replacement throughout mature life. It is unclear whether the loss of hair cells stimulates the proliferation of supporting cells or whether the production of new cells triggers the death of hair cells. We examined the effects of caspase inhibition on spontaneous hair cell death in the chick utricle. Caspase inhibitors reduced the amount of ongoing hair cell death and ongoing supporting cell proliferation in a dose-dependent manner. In isolated sensory epithelia, however, caspase inhibitors did not affect supporting cell proliferation directly. Our data indicate that ongoing hair cell death stimulates supporting cell proliferation in the mature utricle.

  10. Dioscin restores the activity of the anticancer agent adriamycin in multidrug-resistant human leukemia K562/adriamycin cells by down-regulating MDR1 via a mechanism involving NF-κB signaling inhibition.

    Science.gov (United States)

    Wang, Lijuan; Meng, Qiang; Wang, Changyuan; Liu, Qi; Peng, Jinyong; Huo, Xiaokui; Sun, Huijun; Ma, Xiaochi; Liu, Kexin

    2013-05-24

    The purpose of this study was to investigate the ameliorating effect of dioscin (1) on multidrug resistance (MDR) in adriamycin (ADR)-resistant erythroleukemic cells (K562/adriamycin, K562/ADR) and to clarify the molecular mechanisms involved. High levels of multidrug resistance 1 (MDR1) mRNA and protein and reduced ADR retention were found in K562/ADR cells compared with parental cells (K562). Dioscin (1), a constituent of plants in the genus Discorea, significantly inhibited MDR1 mRNA and protein expression and MDR1 promoter and nuclear factor κ-B (NF-κB) activity in K562/ADR cells. MDR1 mRNA and protein suppression resulted in the subsequent recovery of intracellular drug accumulation. Additionally, inhibitor κB-α (IκB-α) degradation was inhibited by 1. Dioscin (1) reversed ADR-induced MDR by down-regulating MDR1 expression by a mechanism that involves the inhibition of the NF-κB signaling pathway. These findings provide evidence to support the further investigation of the clinical application of dioscin (1) as a chemotherapy adjuvant. PMID:23621869

  11. E-cadherin mediates contact inhibition of proliferation through Hippo signaling-pathway components

    OpenAIRE

    Kim, Nam-Gyun; Koh, Eunjin; Chen, Xiao; Gumbiner, Barry M.

    2011-01-01

    Contact inhibition of cell growth is essential for embryonic development and maintenance of tissue architecture in adult organisms, and the growth of tumors is characterized by a loss of contact inhibition of proliferation. The recently identified Hippo signaling pathway has been implicated in contact inhibition of proliferation as well as organ size control. The modulation of the phosphorylation and nuclear localization of Yes-associated protein (YAP) by the highly conserved kinase cascade o...

  12. Rap1 spatially controls ArhGAP29 to inhibit Rho signaling during endothelial barrier regulation

    NARCIS (Netherlands)

    Post, A.; Pannekoek, W. J.; Ponsioen, B.; Vliem, M. J.; Bos, J. L.

    2015-01-01

    The small GTPase Rap1 controls the actin cytoskeleton by regulating Rho GTPase signaling. We recently established that the Rap1 effectors Radil and Rasip1, together with the Rho GTPase activating protein ArhGAP29, mediate Rap1-induced inhibition of Rho signaling in the processes of epithelial cell s

  13. Pharmacologic inhibition of JAK-STAT signaling promotes hair growth.

    Science.gov (United States)

    Harel, Sivan; Higgins, Claire A; Cerise, Jane E; Dai, Zhenpeng; Chen, James C; Clynes, Raphael; Christiano, Angela M

    2015-10-01

    Several forms of hair loss in humans are characterized by the inability of hair follicles to enter the growth phase (anagen) of the hair cycle after being arrested in the resting phase (telogen). Current pharmacologic therapies have been largely unsuccessful in targeting pathways that can be selectively modulated to induce entry into anagen. We show that topical treatment of mouse and human skin with small-molecule inhibitors of the Janus kinase (JAK)-signal transducer and activator of transcription (STAT) pathway results in rapid onset of anagen and subsequent hair growth. We show that JAK inhibition regulates the activation of key hair follicle populations such as the hair germ and improves the inductivity of cultured human dermal papilla cells by controlling a molecular signature enriched in intact, fully inductive dermal papillae. Our findings open new avenues for exploration of JAK-STAT inhibition for promotion of hair growth and highlight the role of this pathway in regulating the activation of hair follicle stem cells.

  14. Pharmacologic inhibition of JAK-STAT signaling promotes hair growth.

    Science.gov (United States)

    Harel, Sivan; Higgins, Claire A; Cerise, Jane E; Dai, Zhenpeng; Chen, James C; Clynes, Raphael; Christiano, Angela M

    2015-10-01

    Several forms of hair loss in humans are characterized by the inability of hair follicles to enter the growth phase (anagen) of the hair cycle after being arrested in the resting phase (telogen). Current pharmacologic therapies have been largely unsuccessful in targeting pathways that can be selectively modulated to induce entry into anagen. We show that topical treatment of mouse and human skin with small-molecule inhibitors of the Janus kinase (JAK)-signal transducer and activator of transcription (STAT) pathway results in rapid onset of anagen and subsequent hair growth. We show that JAK inhibition regulates the activation of key hair follicle populations such as the hair germ and improves the inductivity of cultured human dermal papilla cells by controlling a molecular signature enriched in intact, fully inductive dermal papillae. Our findings open new avenues for exploration of JAK-STAT inhibition for promotion of hair growth and highlight the role of this pathway in regulating the activation of hair follicle stem cells. PMID:26601320

  15. Rapid induction of apoptosis by PI3K inhibitors is dependent upon their transient inhibition of RAS-ERK signaling

    OpenAIRE

    Will, Marie; Qin, Alice Can Ran; Toy, Weiyi; Yao, Zhan; Rodrik-Outmezguine, Vanessa; Schneider, Claudia; Huang, Xiaodong; Monian, Prashant; JIANG, XUEJUN; de Stanchina, Elisa; Baselga, Jose; Liu, Ningshu; Chandarlapaty, Sarat; Rosen, Neal

    2014-01-01

    The effects of selective PI3K and AKT inhibitors were compared in human tumor cell lines in which the pathway is dysregulated. Both caused inhibition of AKT, relief of feedback inhibition of RTKs, and growth arrest. However, only the PI3K inhibitors caused rapid induction of cell death. In seeking a mechanism for this phenomenon, we found that PI3K inhibition, but not AKT inhibition, causes rapid inhibition of wild type RAS and of RAF/MEK/ERK signaling. Inhibition of RAS-ERK signaling is tran...

  16. Fasudil inhibits platelet-derived growth factor-induced human pulmonary artery smooth muscle cell proliferation by up-regulation of p27kip1 via the ERK signal pathway

    Institute of Scientific and Technical Information of China (English)

    LIU Ai-jun; LING Feng; WANG Dong; WANG Qiang; L(U) Xiao-dong; LIU Ying-long

    2011-01-01

    Background RhoA/ Rho kinase (ROCK) pathway is involved in pulmonary arterial hypertension (PAH) and pulmonary artery smooth muscle cell (PASMC) proliferation. Inhibition of ROCK has been proposed as a treatment for PAH. But the mechanism of RhoA/ROCK pathway and its downstream signaling in proliferation of human PASMCs is unclear. We investigated the effect of fasudil, a selective ROCK inhibitor, on platelet-derived growth factor (PDGF) induced human PASMC proliferation, and the possible association between RhoA/ROCK and extracellular signal-regulated kinase (ERK),p27KiP1.Methods Human PASMCs were cultured with the stimulation of 10 ng/ml PDGF, and different concentrations of fasudil were added before the addition of mitogen. Cell viability and cell cycle were determined with MTT and flow cytometry respectively. ROCK activity, ERK activity and protein expression of proliferating cell nuclear angigen (PCNA) and p27Kip1 were measured by immunoblotting.Results By MTT assay, PDGF significantly increased the OD value that represented human PASMC proliferation, and pretreatment with fasudil significantly reversed this effect in a dose-dependent manner. After PDGF stimulation, the percentage of cells in S phase increased dramatically from 15.6% to 24.3%, while the percentage in G0/G1 phase was reduced from 80.6% to 59%. And pretreatment with fasudil reversed the cell cycle effect of PDGF significantly in a dose-dependent manner. PDGF markedly induced ROCK activity and ERK activity with a peak at 15 minutes, which were significantly inhibited by fasudil. In addition, fasudil significantly inhibited PDGF-induced PCNA expression and fasudil also upregulated p27Kip1 expression in human PASMCs, which decreased after PDGF stimulation.Conclusion RhoA/ROCK is vital for PDFG-induced human PASMC proliferation, and fasudil effectively inhibited PDGF-induced human PASMC proliferation by up-regulation of p27Kip1, which may be associated with inhibition of ERK activity.

  17. Glossogyne tenuifolia Extract Inhibits TNF-α-Induced Expression of Adhesion Molecules in Human Umbilical Vein Endothelial Cells via Blocking the NF-kB Signaling Pathway.

    Science.gov (United States)

    Hsuan, Chin-Feng; Hsu, Hsia-Fen; Tseng, Wei-Kung; Lee, Thung-Lip; Wei, Yu-Feng; Hsu, Kwan-Lih; Wu, Chau-Chung; Houng, Jer-Yiing

    2015-01-01

    Chronic inflammation plays a pivotal role in the development of atherosclerosis, where the pro-inflammatory cytokine-induced expression of endothelial adhesion molecules and the recruitment of monocytes are the crucial events leading to its pathogenesis. Glossogyne tenuifolia ethanol extract (GTE) is shown to have potent anti-inflammatory and antioxidant activities. We evaluated the effects of GTE and its major components, luteolin (lut), luteolin-7-glucoside (lut-7-g), and oleanolic acid (OA) on TNF-α-induced expression of adhesion molecules in human umbilical vein endothelial cells (HUVECs). The results demonstrated that GTE, lut, and lut-7-g attenuated the expression of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) in TNF-α-activated HUVECs, and inhibited the adhesion of monocytes to TNF-α-activated HUVECs. The TNF-α-induced mRNA expression of ICAM-1 and VCAM-1 was also suppressed, revealing their inhibitory effects at the transcriptional level. Furthermore, GTE, lut, and lut-7-g blocked the TNF-α-induced degradation of nuclear factor-kB inhibitor (IkB), an indicator of the activation of nuclear factor-kB (NF-kB). In summary, GTE and its bioactive components were effective in preventing the adhesion of monocytes to cytokine-activated endothelium by the inhibition of expression of adhesion molecules, which in turn is mediated through blocking the activation and nuclear translocation of NF-kB. The current results reveal the therapeutic potential of GTE in atherosclerosis. PMID:26393541

  18. Glossogyne tenuifolia Extract Inhibits TNF-α-Induced Expression of Adhesion Molecules in Human Umbilical Vein Endothelial Cells via Blocking the NF-kB Signaling Pathway

    Directory of Open Access Journals (Sweden)

    Chin-Feng Hsuan

    2015-09-01

    Full Text Available Chronic inflammation plays a pivotal role in the development of atherosclerosis, where the pro-inflammatory cytokine-induced expression of endothelial adhesion molecules and the recruitment of monocytes are the crucial events leading to its pathogenesis. Glossogyne tenuifolia ethanol extract (GTE is shown to have potent anti-inflammatory and antioxidant activities. We evaluated the effects of GTE and its major components, luteolin (lut, luteolin-7-glucoside (lut-7-g, and oleanolic acid (OA on TNF-α-induced expression of adhesion molecules in human umbilical vein endothelial cells (HUVECs. The results demonstrated that GTE, lut, and lut-7-g attenuated the expression of intercellular adhesion molecule-1 (ICAM-1 and vascular cell adhesion molecule-1 (VCAM-1 in TNF-α-activated HUVECs, and inhibited the adhesion of monocytes to TNF-α-activated HUVECs. The TNF-α-induced mRNA expression of ICAM-1 and VCAM-1 was also suppressed, revealing their inhibitory effects at the transcriptional level. Furthermore, GTE, lut, and lut-7-g blocked the TNF-α-induced degradation of nuclear factor-kB inhibitor (IkB, an indicator of the activation of nuclear factor-kB (NF-kB. In summary, GTE and its bioactive components were effective in preventing the adhesion of monocytes to cytokine-activated endothelium by the inhibition of expression of adhesion molecules, which in turn is mediated through blocking the activation and nuclear translocation of NF-kB. The current results reveal the therapeutic potential of GTE in atherosclerosis.

  19. Polysaccharide from Inonotus obliquus inhibits migration and invasion in B16-F10 cells by suppressing MMP-2 and MMP-9 via downregulation of NF-κB signaling pathway.

    Science.gov (United States)

    Lee, Ki Rim; Lee, Jong Seok; Kim, Young Rae; Song, In Gyu; Hong, Eock Kee

    2014-05-01

    Polysaccharides derived from Inonotus obliquus (PIO) are known to possess multiple pharmacological activities including antitumor activity. However, the possible molecular mechanisms of these activities are unknown. In the present study, we determined the anti-metastatic potential and signaling pathways of PIO in the highly metastatic B16-F10 mouse melanoma cell line in vitro. We found that PIO suppressed the migration and invasive ability of B16-F10 cells and decreased the expression levels and activities of matrix metalloproteinase (MMP)-2 and MMP-9. In addition, PIO decreased the phosphorylation levels of extracellular signal-regulated protein kinase (ERK), c-Jun N-terminal kinase (JNK) and p38 mitogen-activated protein kinase (MAPK); PIO also decreased the expression level of cyclooxygenase (COX)‑2 and inhibited the nuclear translocation of nuclear factor κB (NF-κB) in B16-F10 melanoma cells. These results suggest that PIO could suppress the invasion and migration of B16-F10 melanoma cells by reducing the expression levels and activities of MMP-2 and MMP-9 through suppressing MAPK, COX-2 and NF-κB signaling pathways. PMID:24677090

  20. Rhomboids, signalling and cell biology.

    Science.gov (United States)

    Freeman, Matthew

    2016-06-15

    Here, I take a somewhat personal perspective on signalling control, focusing on the rhomboid-like superfamily of proteins that my group has worked on for almost 20 years. As well as describing some of the key and recent advances, I attempt to draw out signalling themes that emerge. One important message is that the genetic and biochemical perspective on signalling has tended to underplay the importance of cell biology. There is clear evidence that signalling pathways exploit the control of intracellular trafficking, protein quality control and degradation and other cell biological phenomena, as important regulatory opportunities.

  1. Thyroid hormone receptor β1 suppresses proliferation and migration by inhibiting PI3K/Akt signaling in human colorectal cancer cells.

    Science.gov (United States)

    Zhu, Lei; Tian, Guangang; Yang, Qin; De, Gejing; Zhang, Zhigang; Wang, Yahui; Nie, Huizhen; Zhang, Yanli; Yang, Xiaomei; Li, Jun

    2016-09-01

    Thyroid hormone receptor β1 (TRβ1) is a ligand‑dependent transcription factor that belongs to the superfamily of nuclear receptors. TRβ1 has been found to act as a tumor suppressor in many solid tumors including breast cancer and hepatocellular carcinoma, but its role in the progression of human colorectal cancer (CRC) remains unclear. In this study, microarray data analysis revealed that TRβ1 mRNA was downregulated in CRC tumors compared with that in the normal counterparts in both The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) datasets. Using a CRC tissue microarray (TMA), we confirmed that the expression of TRβ1 was decreased in human CRC tumor tissues in contrast to normal colorectal mucosal tissues. Notably, the TRβ1 expression was strongly correlated with tumor size (p=0.045). Furthermore, we found that CRC cell proliferation and migration were significantly inhibited by TRβ1 overexpression in vitro. Mechanistic studies indicated that activated phosphorylated Akt was clearly suppressed by TRβ1 in the CRC tissues and cells. In conclusion, this study provides evidence that TRβ1 plays a critical role in the progression of CRC via the PI3K/Akt pathway, and the TRβ1 gene may represent a novel target for CRC therapeutics. PMID:27431682

  2. Dryofragin inhibits the migration and invasion of human osteosarcoma U2OS cells by suppressing MMP-2/9 and elevating TIMP-1/2 through PI3K/AKT and p38 MAPK signaling pathways.

    Science.gov (United States)

    Su, Yan; Wan, Daqian; Song, Wenqi

    2016-08-01

    Dryofragin, a phloroglucinol derivative extracted from Dryopteris fragrans (L.) Schott, was found to inhibit proliferation and induce apoptosis of tumor cells. However, the mechanism involved in the suppression of cancer cell metastasis by dryofragin remains unclear. Our study investigated the mechanisms for the antitumor properties of dryofragin on the migration and invasion of human osteosarcoma U2OS cells. Dryofragin suppressed the migration and invasive ability of U2OS cells, and it decreased the expression of MMP-2 and MMP-9 and elevated the expression of TIMP-1 and TIMP-2. Western blotting assays indicated that dryofragin was effective in suppressing the phosphorylation of phosphatidylinositide-3 kinase (PI3K), Akt, and p38 MAPK. These results suggest that dryofragin inhibited U2OS cell migration and invasion by reducing the expression of MMP-2 and MMP-9 and elevating the expression of TIMP-1 and TIMP-2 through the PI3K/AKT and p38 MAPK signaling pathways. Above all, we conclude that dryofragin represents an anti-invasive agent and may potentially be applicable in osteosarcoma therapy. PMID:27243922

  3. Antileukemia Effect of Ciclopirox Olamine Is Mediated by Downregulation of Intracellular Ferritin and Inhibition β-Catenin-c-Myc Signaling Pathway in Glucocorticoid Resistant T-ALL Cell Lines.

    Science.gov (United States)

    Wu, Jianrong; Liu, Huajun; Zhang, Ge; Gu, Ling; Zhang, Yanle; Gao, Ju; Wei, Yuquan; Ma, Zhigui

    2016-01-01

    Ciclopirox olamine (CPX) is an antifungal drug that has been reported to have antitumor effects. In this study we investigated the antileukemia effects and the possible mechanisms of CPX on glucocorticoid (GC)-resistant T-cell acute lymphoblastic leukemia (T-ALL) cell lines. The results indicated that CPX inhibited the growth of GC-resistant T-ALL cells in a time- and dose-dependent manner, and this effect was closely correlated with the downregulation of intracellular ferritin. CPX induced cell cycle arrest at G1 phase by upregulation of cyclin-dependent kinase (CDK) inhibitor of p21 and downregulation of the expressions of cyclin D, retinoblastoma protein (Rb), and phosphorylated Rb (pRb). CPX also enhanced apoptotic cell death by downregulation of anti-apoptotic proteins such as Bcl-2, Bcl-xL, and Mcl-1. More importantly, CPX demonstrated a strong synergistic antileukemia effect with GC and this effect was mediated, at least in part, by inhibition of the β-catenin-c-Myc signaling pathway. These findings suggest that CPX could be a promising antileukemia drug, and modulation of the intracellular ferritin expression might be an effective method in the treatment of ALL. Therefore, integrating CPX into the current GC-containing ALL protocols could lead to the improvement of the outcome of ALL, especially GC-resistant ALL. PMID:27551974

  4. Anti-Inflammatory Effects of Melandrii Herba Ethanol Extract via Inhibition of NF-κB and MAPK Signaling Pathways and Induction of HO-1 in RAW 264.7 Cells and Mouse Primary Macrophages

    Directory of Open Access Journals (Sweden)

    Yun Hee Jeong

    2016-06-01

    Full Text Available Melandrii Herba (MH is a traditional Asian medicinal herb used to treat breast cancer, anuria, and diseases of lactation. However, its biological properties and molecular mechanisms have not been fully elucidated. The purpose of this study was to investigate the anti-inflammatory activity and underlying molecular mechanism of MH ethanol extract (MHE on the lipopolysaccharide (LPS-mediated inflammatory response in macrophages. MHE cytotoxicity was determined using a cell counting kit (CCK assay. The effects of MHE on the production of NO, inflammatory cytokines, and related proteins and mRNAs were determined using the Griess test, ELISA, Western blotting, and real-time RT-PCR, respectively. In addition, intracellular signaling pathways, such as NF-κB, MAPK, and HO-1, were analyzed using Western blotting. Our results revealed that MHE treatment significantly inhibited the secretion of NO and inflammatory cytokines, including TNF-α, IL-6, and IL-1β in macrophages, at sub-cytotoxic concentrations. Furthermore, MHE treatment inhibited iNOS expression and induced HO-1 expression. Finally, the transcriptional activities of NF-κB and MAPK activation were significantly suppressed by MHE in LPS-stimulated macrophages. The results indicate that MHE exerts anti-inflammatory effects by suppressing inflammatory mediator production via NF-κB and MAPK signaling pathways inhibition and induction of HO-1 expression in macrophages. Therefore, our results suggest the potential value of MHE as an inflammatory therapeutic agent developed from a natural substance.

  5. Anti-Inflammatory Effects of Melandrii Herba Ethanol Extract via Inhibition of NF-κB and MAPK Signaling Pathways and Induction of HO-1 in RAW 264.7 Cells and Mouse Primary Macrophages.

    Science.gov (United States)

    Jeong, Yun Hee; Oh, You-Chang; Cho, Won-Kyung; Lee, Bohyoung; Ma, Jin Yeul

    2016-01-01

    Melandrii Herba (MH) is a traditional Asian medicinal herb used to treat breast cancer, anuria, and diseases of lactation. However, its biological properties and molecular mechanisms have not been fully elucidated. The purpose of this study was to investigate the anti-inflammatory activity and underlying molecular mechanism of MH ethanol extract (MHE) on the lipopolysaccharide (LPS)-mediated inflammatory response in macrophages. MHE cytotoxicity was determined using a cell counting kit (CCK) assay. The effects of MHE on the production of NO, inflammatory cytokines, and related proteins and mRNAs were determined using the Griess test, ELISA, Western blotting, and real-time RT-PCR, respectively. In addition, intracellular signaling pathways, such as NF-κB, MAPK, and HO-1, were analyzed using Western blotting. Our results revealed that MHE treatment significantly inhibited the secretion of NO and inflammatory cytokines, including TNF-α, IL-6, and IL-1β in macrophages, at sub-cytotoxic concentrations. Furthermore, MHE treatment inhibited iNOS expression and induced HO-1 expression. Finally, the transcriptional activities of NF-κB and MAPK activation were significantly suppressed by MHE in LPS-stimulated macrophages. The results indicate that MHE exerts anti-inflammatory effects by suppressing inflammatory mediator production via NF-κB and MAPK signaling pathways inhibition and induction of HO-1 expression in macrophages. Therefore, our results suggest the potential value of MHE as an inflammatory therapeutic agent developed from a natural substance. PMID:27338335

  6. Inhibition of VCAM-1 expression on mouse vascular smooth muscle cells by lobastin via downregulation of p38, ERK 1/2 and NF-κB signaling pathways.

    Science.gov (United States)

    Lee, Kyoungran; Yim, Joung-Han; Lee, Hong-Kum; Pyo, Suhkneung

    2016-01-01

    Atherosclerosis is a chronic inflammatory disease, the progression of which is associated with the increased expression of cell adhesion molecules on vascular smooth muscle cells (VSMCs). Lobastin is a new pseudodepsidone isolated from Stereocaulon alpinum, Antarctic lichen, which is known to have antioxidant and antibacterial activities. However, the nature of the biological effects of lobastin still remains unclear. In the present study, we examine the effect of lobastin on the expression of vascular cell adhesion molecules (VCAM-1) induced by TNF-α in the cultured mouse VSMC cell line, MOVAS-1. Pretreatment of VSMCs for 2 h with lobastin (0.1-10 μg/ml) concentration-dependently inhibited TNF-α-induced protein expression of VCAM-1. Lobastin also inhibited TNF-α-induced production of intracellular reactive oxygen species (ROS). Lobastin abrogated TNF-α-induced phosphorylation of p38 and ERK 1/2, but not JNK, and also inhibited TNF-α-induced NK-κB activation. In addition, lobastin suppressed TNF-α-induced IκB kinase activation, subsequent degradation of IκBα and nuclear translocation of p65 NF-κB. Our results indicate that lobastin downregulates the TNF-α-mediated induction of VCAM-1 in VSMC by inhibiting the p38, ERK 1/2 and NF-κB signaling pathways and intracellular ROS generation. Thus, lobastin may be an important regulator of inflammation in the atherosclerotic lesion and a novel therapeutic drug for the treatment of atherosclerosis.

  7. Hedyotis diffusa Willd inhibits colorectal cancer growth in vivo via inhibition of STAT3 signaling pathway.

    Science.gov (United States)

    Cai, Qiaoyan; Lin, Jiumao; Wei, Lihui; Zhang, Ling; Wang, Lili; Zhan, Youzhi; Zeng, Jianwei; Xu, Wei; Shen, Aling; Hong, Zhenfeng; Peng, Jun

    2012-01-01

    Signal Transducer and Activator of Transcription 3 (STAT3), a common oncogenic mediator, is constitutively activated in many types of human cancers; therefore it is a major focus in the development of novel anti-cancer agents. Hedyotis diffusa Willd has been used as a major component in several Chinese medicine formulas for the clinical treatment of colorectal cancer (CRC). However, the precise mechanism of its anti-tumor activity remains largely unclear. Using a CRC mouse xenograft model, in the present study we evaluated the effect of the ethanol extract of Hedyotis diffusa Willd (EEHDW) on tumor growth in vivo and investigated the underlying molecular mechanisms. We found that EEHDW reduced tumor volume and tumor weight, but had no effect on body weight gain in CRC mice, demonstrating that EEHDW can inhibit CRC growth in vivo without apparent adverse effect. In addition, EEHDW treatment suppressed STAT3 phosphorylation in tumor tissues, which in turn resulted in the promotion of cancer cell apoptosis and inhibition of proliferation. Moreover, EEHDW treatment altered the expression pattern of several important target genes of the STAT3 signaling pathway, i.e., decreased expression of Cyclin D1, CDK4 and Bcl-2 as well as up-regulated p21 and Bax. These results suggest that suppression of the STAT3 pathway might be one of the mechanisms by which EEHDW treats colorectal cancer. PMID:22754353

  8. 3,5,4′-Trimethoxystilbene, a natural methoxylated analog of resveratrol, inhibits breast cancer cell invasiveness by downregulation of PI3K/Akt and Wnt/β-catenin signaling cascades and reversal of epithelial–mesenchymal transition

    Energy Technology Data Exchange (ETDEWEB)

    Tsai, Jie-Heng [Institute of Biochemistry and Biotechnology, Chung Shan Medical University, Taichung 402, Taiwan, ROC (China); Hsu, Li-Sung [Institute of Biochemistry and Biotechnology, Chung Shan Medical University, Taichung 402, Taiwan, ROC (China); Clinical Laboratory, Chung Shan Medical University Hospital, Taichung 402, Taiwan, ROC (China); Lin, Chih-Li [Institute of Medicine, Chung Shan Medical University, Taichung 402, Taiwan, ROC (China); Department of Medical Research, Chung Shan Medical University Hospital, Taichung 402, Taiwan, ROC (China); Hong, Hui-Mei [Department of Medical Research, Chung Shan Medical University Hospital, Taichung 402, Taiwan, ROC (China); Department of Biomedical Sciences, Chung Shan Medical University, Taichung 402, Taiwan, ROC (China); Pan, Min-Hsiung [Department of Seafood Science, National Kaohsiung Marine University, Kaohsiung 811, Taiwan, ROC (China); Way, Tzong-Der [Department of Biological Science and Technology, College of Life Sciences, China Medical University, Taichung 40402, Taiwan, ROC (China); Chen, Wei-Jen, E-mail: cwj519@csmu.edu.tw [Department of Medical Research, Chung Shan Medical University Hospital, Taichung 402, Taiwan, ROC (China); Department of Biomedical Sciences, Chung Shan Medical University, Taichung 402, Taiwan, ROC (China)

    2013-11-01

    The molecular basis of epithelial–mesenchymal transition (EMT) functions as a potential therapeutic target for breast cancer because EMT may endow breast tumor-initiating cells with stem-like characteristics and enable the dissemination of breast cancer cells. We have recently verified the antitumor activity of 3,5,4′-trimethoxystilbene (MR-3), a naturally methoxylated derivative of resveratrol, in colorectal cancer xenografts via an induction of apoptosis. The effect of MR-3 on EMT and the invasiveness of human MCF-7 breast adenocarcinoma cell line were also explored. We found that MR-3 significantly increased epithelial marker E-cadherin expression and triggered a cobblestone-like morphology of MCF-7 cells, while reciprocally decreasing the expression of mesenchymal markers, such as snail, slug, and vimentin. In parallel with EMT reversal, MR-3 downregulated the invasion and migration of MCF-7 cells. Exploring the action mechanism of MR-3 on the suppression of EMT and invasion indicates that MR-3 markedly reduced the expression and nuclear translocation of β-catenin, accompanied with the downregulation of β-catenin target genes and the increment of membrane-bound β-catenin. These results suggest the involvement of Wnt/β-catenin signaling in the MR-3-induced EMT reversion of MCF-7 cells. Notably, MR-3 restored glycogen synthase kinase-3β activity by inhibiting the phosphorylation of Akt, the event required for β-catenin destruction via a proteasome-mediated system. Overall, these findings indicate that the anti-invasive activity of MR-3 on MCF-7 cells may result from the suppression of EMT via down-regulating phosphatidylinositol 3-kinase (PI3K)/AKT signaling, and consequently, β-catenin nuclear translocation. These occurrences ultimately lead to the blockage of EMT and the invasion of breast cancer cells. - Highlights: • MR-3 blocked MCF-7 cell invasion by inducing a reversal of EMT. • Wnt/β-catenin signaling is involved in MR-3-induced EMT

  9. 3,5,4′-Trimethoxystilbene, a natural methoxylated analog of resveratrol, inhibits breast cancer cell invasiveness by downregulation of PI3K/Akt and Wnt/β-catenin signaling cascades and reversal of epithelial–mesenchymal transition

    International Nuclear Information System (INIS)

    The molecular basis of epithelial–mesenchymal transition (EMT) functions as a potential therapeutic target for breast cancer because EMT may endow breast tumor-initiating cells with stem-like characteristics and enable the dissemination of breast cancer cells. We have recently verified the antitumor activity of 3,5,4′-trimethoxystilbene (MR-3), a naturally methoxylated derivative of resveratrol, in colorectal cancer xenografts via an induction of apoptosis. The effect of MR-3 on EMT and the invasiveness of human MCF-7 breast adenocarcinoma cell line were also explored. We found that MR-3 significantly increased epithelial marker E-cadherin expression and triggered a cobblestone-like morphology of MCF-7 cells, while reciprocally decreasing the expression of mesenchymal markers, such as snail, slug, and vimentin. In parallel with EMT reversal, MR-3 downregulated the invasion and migration of MCF-7 cells. Exploring the action mechanism of MR-3 on the suppression of EMT and invasion indicates that MR-3 markedly reduced the expression and nuclear translocation of β-catenin, accompanied with the downregulation of β-catenin target genes and the increment of membrane-bound β-catenin. These results suggest the involvement of Wnt/β-catenin signaling in the MR-3-induced EMT reversion of MCF-7 cells. Notably, MR-3 restored glycogen synthase kinase-3β activity by inhibiting the phosphorylation of Akt, the event required for β-catenin destruction via a proteasome-mediated system. Overall, these findings indicate that the anti-invasive activity of MR-3 on MCF-7 cells may result from the suppression of EMT via down-regulating phosphatidylinositol 3-kinase (PI3K)/AKT signaling, and consequently, β-catenin nuclear translocation. These occurrences ultimately lead to the blockage of EMT and the invasion of breast cancer cells. - Highlights: • MR-3 blocked MCF-7 cell invasion by inducing a reversal of EMT. • Wnt/β-catenin signaling is involved in MR-3-induced EMT

  10. Blockade of Wnt signaling inhibits angiogenesis and tumor growth in hepatocellular carcinoma

    OpenAIRE

    J. Hu; Dong, A.; Fernandez-Ruiz, V. (Verónica); Shan, J.; Kawa, M. (Milosz); Martinez-Anso, E. (Eduardo); J. Prieto; Qian, C

    2009-01-01

    Aberrant activation of Wnt signaling plays an important role in hepatocarcinogenesis. In addition to direct effects on tumor cells, Wnt signaling might be involved in the organization of tumor microenvironment. In this study, we have explored whether Wnt signaling blockade by exogenous expression of Wnt antagonists could inhibit tumor angiogenesis and control tumor growth. Human Wnt inhibitory factor 1 (WIF1) and secreted frizzled-related protein 1 (sFRP1) were each fused with Fc fragment of ...

  11. Doxycycline inhibits leukemic cell migration via inhibition of matrix metalloproteinases and phosphorylation of focal adhesion kinase

    OpenAIRE

    WANG, CHUNHUAI; Xiang, Ru; ZHANG, XIANGZHONG; CHEN, YUNXIAN

    2015-01-01

    Doxycycline, a tetracycline-based antibiotic, has been reported to attenuate melanoma cell migration through inhibiting the focal adhesion kinase (FAK) signaling pathway. However, it remains to be elucidated whether doxycycline exerts this effect on leukemia cell migration. The present study aimed to examine the role of doxycycline in leukemia cell migration. The invasion capacities of the human leukemia cell lines KG1a (acute myelogenous leukemia) and K562 (chronic myelogenous leukemia) were...

  12. Inhibition of Wnt signaling by cucurbitacin B in breast cancer cells: reduction of Wnt-associated proteins and reduced translocation of galectin-3-mediated β-catenin to the nucleus.

    Science.gov (United States)

    Dakeng, Sumana; Duangmano, Suwit; Jiratchariyakul, Weena; U-Pratya, Yaowalak; Bögler, Oliver; Patmasiriwat, Pimpicha

    2012-01-01

    The cucurbitacins are tetracyclic triterpenes found in plants of the family Cucurbitaceae. Cucurbitacins have been shown to have anti-cancer and anti-inflamatory activities. We investigated the anti-cancer activity of cucurbitacin B extracted from Thai medicinal plant Trichosanthes cucumerina Linn. Cell viability was assessed by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. Results indicated that cucurbitacin B from T. cucumerina Linn. has a cytotoxic effect on breast cancer cell lines SKBR-3 and MCF-7 with an IC50 of 4.60 and 88.75 µg/ml, respectively. Growth inhibition was attributed to G2/M phase arrest and apoptosis. Cyclin D1, c-Myc, and β-catenin expression levels were reduced. Western blot analysis showed increased PARP cleavage and decreased Wnt-associated signaling molecules β-catenin, galectin-3, cyclin D1 and c-Myc, and corresponding changes in phosphorylated GSK-3β levels. Cucurbitacin B treatment inhibited translocation to the nucleus of β-catenin and galectin-3. The depletion of β-catenin and galectin-3 in the nucleus was confirmed by cellular protein fractionation. T-cell factor (TCF)/lymphoid enhancer factor (LEF)-dependent transcriptional activity was disrupted in cucurbitacin B treated cells as tested by a TCF reporter assay. The relative luciferase activity was reduced when we treated cells with cucurbitacin B compound for 24 h. Our data suggest that cucurbitacin B may in part induce apoptosis and exert growth inhibitory effect via interruption the Wnt signaling.

  13. INHIBITION OF ERN1 SIGNALING ENZYME AFFECTS HYPOXIC REGULATION OF THE EXPRESSION OF E2F8, EPAS1, HOXC6, ATF3, TBX3 AND FOXF1 GENES IN U87 GLIOMA CELLS.

    Science.gov (United States)

    Minchenko, O H; Tsymbal, D O; Minchenko, D O; Kovalevska, O V; Karbovskyi, L L; Bikfalvi, A

    2015-01-01

    Hypoxia as well as the endoplasmic reticulum stress are important factors of malignant tumor growth and control of the expression of genes, which regulate numerous metabolic processes and cell proliferation. Furthermore, blockade of ERN1 (endoplasmic reticulum to nucleus 1) suppresses cell proliferation and tumor growth. We studied the effect of hypoxia on the expression of genes encoding the transcription factors such as E2F8 (E2F transcription factor 8), EPAS1 (endothelial PAS domain protein 1), TBX3 (T-box 3), ATF3 (activating transcription factor 3), FOXF1 (forkhead box F), and HOXC6 (homeobox C6) in U87 glioma cells with and without ERN1 signaling enzyme function. We have established that hypoxia enhances the expression of HOXC6, E2F8, ATF3, and EPAS1 genes but does not change TBX3 and FOXF1 gene expression in glioma cells with ERNI function. At the same time, the expression level of all studied genes is strongly decreased, except for TBX3 gene, in glioma cells without ERN1 function. Moreover, the inhibition of ERN1 signaling enzyme function significantly modifies the effect of hypoxia on the expression of these transcription factor genes. removes or introduces this regulation as well as changes a direction or magnitude of hypoxic regulation. Present study demonstrates that fine-tuning of the expression of proliferation related genes depends upon hypoxia and ERN1-mediated endoplasmic reticulum stress signaling and correlates with slower proliferation rate of glioma cells without ERN1 function. PMID:26255341

  14. Helicobacter pylori inhibits dendritic cell maturation via interleukin-10-mediated activation of the signal transducer and activator of transcription 3 pathway.

    Science.gov (United States)

    Rizzuti, David; Ang, Michelle; Sokollik, Christiane; Wu, Ted; Abdullah, Majd; Greenfield, Laura; Fattouh, Ramzi; Reardon, Colin; Tang, Michael; Diao, Jun; Schindler, Christian; Cattral, Mark; Jones, Nicola L

    2015-01-01

    Helicobacter pylori infects the human gastric mucosa causing a chronic infection that is the primary risk factor for gastric cancer development. Recent studies demonstrate that H. pylori promotes tolerogenic dendritic cell (DC) development indicating that this bacterium evades the host immune response. However, the signaling pathways involved in modulating DC activation during infection remain unclear. Here, we report that H. pylori infection activated the signal transducer and activator of transcription 3 (STAT3) pathway in murine bone marrow-derived DCs (BMDCs) and splenic DCs isolated ex vivo. Isogenic cagA-, cagE-, vacA- and urease-mutants exhibited levels of phosphoSTAT3 that were comparable to in the wild-type (WT) parent strain. H. pylori-infected BMDCs produced increased immunosuppressive IL-10, which activated STAT3 in an autocrine/paracrine fashion. Neutralization of IL-10 prevented H. pylori-mediated STAT3 activation in both BMDCs and splenic DCs. In addition, anti-IL-10 treatment of infected H. pylori-BMDCs was associated with increased CD86 and MHC II expression and enhanced proinflammatory IL-1β cytokine secretion. Finally, increased CD86 and MHC II expression was detected in H. pylori-infected STAT3 knockout DCs when compared to WT controls. Together, these results demonstrate that H. pylori infection induces IL-10 secretion in DCs, which activates STAT3, thereby modulating DC maturation and reducing IL-1β secretion. These findings identify a host molecular mechanism by which H. pylori can manipulate the innate immune response to potentially favor chronic infection and promote carcinogenesis. PMID:25412627

  15. Retinoic acid receptor agonist Am80 inhibits CXCL2 production from microglial BV-2 cells via attenuation of NF-κB signaling.

    Science.gov (United States)

    Takaoka, Yuichiro; Takahashi, Moeka; Kurauchi, Yuki; Hisatsune, Akinori; Seki, Takahiro; Shudo, Koichi; Katsuki, Hiroshi

    2016-09-01

    Accumulating lines of evidence suggest that retinoic acid receptor agonists such as Am80 exerts anti-inflammatory actions in the central nervous system, although detailed mechanisms of the action remain largely unknown. Our previous findings suggest that Am80 provides therapeutic effect on intracerebral hemorrhage in mice via suppression of expression of chemokine (C-X-C motif) ligand 2 (CXCL2). Here we investigated the mechanisms of inhibitory action of Am80 on expression of CXCL2 and other pro-inflammatory factors in microglial BV-2 cells. Pretreatment with Am80 markedly suppressed lipopolysaccharide (LPS)-induced expression of CXCL2 mRNA and release of CXCL2 protein. Am80 had no effect on LPS-induced activation of p38 mitogen-activated protein kinase and extracellular signal-regulated kinase. On the other hand, Am80 prevented LPS-induced nuclear translocation of p65 subunit of NF-κB complex. In addition, total expression levels of p65 and IκBα proteins, as well as of mRNAs encoding p65 and IκBα, were lowered by Am80. Dependence of CXCL2 expression on NF-κB was confirmed by the effect of an NF-κB inhibitor caffeic acid phenethyl ester that abolished LPS-induced CXCL2 expression. Caffeic acid phenethyl ester also abolished LPS-induced expression of inducible nitric oxide synthase, interleukin-1β and tumor necrosis factor α, which may be relevant to the inhibitory effect of Am80 on expression of these pro-inflammatory factors. We additionally found that Am80 attenuated LPS-induced up-regulation of CD14, a co-receptor for Toll-like receptor 4 (TLR4). These results suggest that inhibitory effect on TLR4 signaling mediated by NF-κB pathway underlies the anti-inflammatory action of retinoic acid receptor agonists in microglia. PMID:27351827

  16. A novel berbamine derivative inhibits cell viability and induces apoptosis in cancer stem-like cells of human glioblastoma, via up-regulation of miRNA-4284 and JNK/AP-1 signaling.

    Directory of Open Access Journals (Sweden)

    Fan Yang

    Full Text Available Glioblastoma (GBM is the most common primary brain tumor, accounting for approximately 40% of all central nervous system malignancies. Despite standard treatment consisting of surgical resection, radiotherapy and/or chemotherapy, the prognosis for GBM is poor; with a median survival of 14.6 months. The cancer stem cell or cancer-initiating cell model has provided a new paradigm for understanding development and recurrence of GBM following treatment. Berbamine (BBM is a natural compound derived from the Berberis amurensis plant, and along with its derivatives, has been shown to exhibit antitumor activity in several cancers. Here, we reported that a novel synthetic Berbamine derivative, BBMD3, inhibits cell viability and induces apoptosis of cancer stem-like cells (CSCs in a time- and dose-dependent manner when the CSCs from four GBM patients (PBT003, PBT008, PBT022, and PBT030 were cultured. These CSCs grew in neurospheres and expressed CD133 and nestin as markers. Treatment with BBMD3 destroyed the neurosphere morphology, and led to the induction of apoptosis in the CSCs. Induction of apoptosis in these CSCs is dependent upon activation of caspase-3 and cleavage of poly (ADP-ribose polymerase (PARP. MicroRNA-4284 (miR-4284 was shown to be over-expressed about 4-fold in the CSCs following BBMD3 treatment. Furthermore, transfection of synthetic anti-sense oligonucleotide against human miR-4284 partially blocked the anticancer effects of BBMD3 on the GBM derived CSCs. BBMD3 also increased phosphorylation of the c-Jun N-terminal kinase (JNK/stress-activated protein kinase (SAPK, resulting in an increase expression of phosphorylated c-Jun and total c-Fos; the major components of transcriptional factor AP-1. The JNK-c-Jun/AP-1 signaling pathway plays an important role in the induction of apoptosis in response to UV irradiation and some drug treatments. Targeting glioblastoma stem-like cells with BBMD3 is therefore novel, and may have promise as an

  17. Roundabout4 Suppresses Glioma-Induced Endothelial Cell Proliferation, Migration and Tube Formation in Vitro by Inhibiting VEGR2-Mediated PI3K/AKT and FAK Signaling Pathways

    Directory of Open Access Journals (Sweden)

    Heng Cai

    2015-03-01

    Full Text Available Background and Aims: Endothelial cell (EC proliferation, migration, and tube formation are the critical steps for tumor angiogenesis, which is involved in the formation of new tumor blood vessels. Roundabout4 (Robo4, a new member of Robo proteins family, is specifically expressed in endothelial cells. This study aimed to investigate the effects of Robo4 on glioma-induced endothelial cell proliferation, migration and tube formation in vitro. Methods and Results: We found that Robo4 was endogenously expressed in Human Brain Microvascular Endothelial Cells (HBMECs, while Robo4 was significantly down-regulated in endothelial cells cultured in glioma conditioned medium. Robo4 over-expression remarkably suppressed glioma-induced endothelial cell proliferation, migration and tube formation in vitro. In addition, Robo4 influenced the glioma-induced angiogenesis via binding to its ligand Slit2. Further studies demonstrated that the knockdown of Robo4 up-regulated the phosphorylation of VEGFR2, PI3K, AKT and FAK in EC cultured in glioma conditioned medium. VEGFR2 inhibitor SU-1498, AKT inhibitor LY294002 and FAK inhibitor 14 (FAK inhibitor blocked the Robo4 knockdown-mediated alteration in glioma angiogenesis in vitro. Conclusion: Our results proved that Robo4 suppressed glioma-induced endothelial cell proliferation, migration and tube formation in vitro by inhibiting VEGR2-mediated activation of PI3K/AKT and FAK signaling pathways.

  18. 14-3-3γ Regulates Lipopolysaccharide-Induced Inflammatory Responses and Lactation in Dairy Cow Mammary Epithelial Cells by Inhibiting NF-κB and MAPKs and Up-Regulating mTOR Signaling

    Directory of Open Access Journals (Sweden)

    Lixin Liu

    2015-07-01

    Full Text Available As a protective factor for lipopolysaccharide (LPS-induced injury, 14-3-3γ has been the subject of recent research. Nevertheless, whether 14-3-3γ can regulate lactation in dairy cow mammary epithelial cells (DCMECs induced by LPS remains unknown. Here, the anti-inflammatory effect and lactation regulating ability of 14-3-3γ in LPS-induced DCMECs are investigated for the first time, and the molecular mechanisms responsible for their effects are explored. The results of qRT-PCR showed that 14-3-3γ overexpression significantly inhibited the mRNA expression of tumor necrosis factor-α (TNF-α, interleukin-6 (IL-6, interleukin-1β (IL-1β and inducible nitric oxide synthase (iNOS. Enzyme-linked immunosorbent assay (ELISA analysis revealed that 14-3-3γ overexpression also suppressed the production of TNF-α and IL-6 in cell culture supernatants. Meanwhile, CASY-TT Analyser System showed that 14-3-3γ overexpression clearly increased the viability and proliferation of cells. The results of kit methods and western blot analysis showed that 14-3-3γ overexpression promoted the secretion of triglycerides and lactose and the synthesis of β-casein. Furthermore, the expression of genes relevant to nuclear factor-κB (NF-κB and mitogen-activated protein kinase (MAPKs and lactation-associated proteins were assessed by western blot, and the results suggested that 14-3-3γ overexpression inactivated the NF-κB and MAPK signaling pathways by down-regulating extracellular signal regulated protein kinase (ERK, p38 mitogen-activated protein kinase (p38MAPK and inhibitor of NF-κB (IκB phosphorylation levels, as well as by inhibiting NF-κB translocation. Meanwhile, 14-3-3γ overexpression enhanced the expression levels of β-casein, mammalian target of rapamycin (mTOR, ribosomal protein S6 kinase 1 (S6K1, serine/threonine protein kinase Akt 1 (AKT1, sterol regulatory element binding protein 1 (SREBP1 and peroxisome proliferator-activated receptor gamma

  19. Retraction: "Down-regulation of Notch-1 and Jagged-1 inhibits prostate cancer cell growth, migration and invasion, and induces apoptosis via inactivation of Akt, mTOR, and NF-κB signaling pathways" by Wang et al.

    Science.gov (United States)

    2016-08-01

    The above article, published online on January 5, 2010 in Wiley Online Library (wileyonlinelibrary.com), has been retracted by agreement between the journal Editor in Chief, Gary S. Stein, and Wiley Periodicals, Inc. The retraction has been agreed following an investigation from Wayne State University involving the first author and the corresponding author that found Figure 5A to be inappropriately manipulated. REFERENCE Wang Z, Li Y, Banerjee S, Kong D, Ahmad A, Nogueira V, Hay N, Sarkar FH. 2010. Down-regulation of Notch-1 and Jagged-1 inhibits prostate cancer cell growth, migration and invasion, and induces apoptosis via inactivation of Akt, mTOR, and NF-κB signaling pathways. J Cell Biochem 109:726-736; doi: 10.1002/jcb.22451.

  20. Retraction: "Down-regulation of Notch-1 and Jagged-1 inhibits prostate cancer cell growth, migration and invasion, and induces apoptosis via inactivation of Akt, mTOR, and NF-κB signaling pathways" by Wang et al.

    Science.gov (United States)

    2016-08-01

    The above article, published online on January 5, 2010 in Wiley Online Library (wileyonlinelibrary.com), has been retracted by agreement between the journal Editor in Chief, Gary S. Stein, and Wiley Periodicals, Inc. The retraction has been agreed following an investigation from Wayne State University involving the first author and the corresponding author that found Figure 5A to be inappropriately manipulated. REFERENCE Wang Z, Li Y, Banerjee S, Kong D, Ahmad A, Nogueira V, Hay N, Sarkar FH. 2010. Down-regulation of Notch-1 and Jagged-1 inhibits prostate cancer cell growth, migration and invasion, and induces apoptosis via inactivation of Akt, mTOR, and NF-κB signaling pathways. J Cell Biochem 109:726-736; doi: 10.1002/jcb.22451. PMID:27301887

  1. Stat3 inhibition in neural lineage cells.

    Science.gov (United States)

    Chiba, Tomohiro; Mack, Laura; Delis, Natalia; Brill, Boris; Groner, Bernd

    2012-06-01

    Abstract Deregulation of signal transducer and activator of transcription 3 (Stat3) is attracting attentions in neurological disorders of elderly populations, e.g., Stat3 is inactivated in hippocampal neurons of Alzheimer's disease (AD) brains, whereas it is often constitutively activated in glioblastoma multiforme (GBM), correlating with poor prognosis. Stat3-inhibiting drugs have been intensively developed for chemotherapy based on the fact that GBM, in many cases, are "addicted" to Stat3 activation. Stat3 inhibitors, however, potentially have unfavorable side effects on postmitotic neurons, normal permanent residents in the central nervous system. It is, therefore, of great importance to address detailed cellular responses of neural lineage cells including normal neurons, astrocytes, and neuronal/glial cancer cell lines to several classes of Stat3 inhibitors focusing on their effective concentrations. Here, we picked up five human and mouse cancer cell lines (Neuro-2a and SH-SY5Y neuroblastoma cell lines and Tu-9648, U-87MG, and U-373MG glioblastoma cell lines) and treated with various Stat3 inhibitors. Among them, Stattic, FLLL31, and resveratrol potently suppressed P-Stat3 and cell viability in all the tested cell lines. Stat3 knockdown or expression of dominant-negative Stat3 further sensitized cells to the inhibitors. Expression of familial AD-related mutant amyloid precursor protein sensitized neuronal cells, not glial cells, to Stat3 inhibitors by reducing P-Stat3 levels. Primary neurons and astrocytes also responded to Stat3 inhibitors with similar sensitivities to those observed in cancer cell lines. Thus, Stat3 inhibitors should be carefully targeted to GBM cells to avoid potential neurotoxicity leading to AD-like neuropsychiatric dysfunctions. PMID:25436682