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Sample records for analogues inhibit cell

  1. Migrastatin analogues inhibit canine mammary cancer cell migration and invasion.

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    Kinga Majchrzak

    Full Text Available BACKGROUND: Cancer spread to other organs is the main cause of death of oncological patients. Migration of cancer cells from a primary tumour is the crucial step in the complex process of metastasis, therefore blocking this process is currently the main treatment strategy. Metastasis inhibitors derived from natural products, such as, migrastatin, are very promising anticancer agents. Thus, the aim of our study was to investigate the effect of six migrastatin analogues (MGSTA-1 to 6 on migration and invasion of canine mammary adenocarcinoma cell lines isolated from primary tumours and their metastases to the lungs. Canine mammary tumours constitute a valuable tool for studying multiple aspect of human cancer. RESULTS: OUR RESULTS SHOWED THAT TWO OF SIX FULLY SYNTHETIC ANALOGUES OF MIGRASTATIN: MGSTA-5 and MGSTA-6 were potent inhibitors of canine mammary cancer cells migration and invasion. These data were obtained using the wound healing test, as well as trans-well migration and invasion assays. Furthermore, the treatment of cancer cells with the most effective compound (MGSTA-6 disturbed binding between filamentous F-actin and fascin1. Confocal microscopy analyses revealed that treatment with MGSTA-6 increased the presence of unbound fascin1 and reduced co-localization of F-actin and fascin1 in canine cancer cells. Most likely, actin filaments were not cross-linked by fascin1 and did not generate the typical filopodial architecture of actin filaments in response to the activity of MGSTA-6. Thus, administration of MGSTA-6 results in decreased formation of filopodia protrusions and stress fibres in canine mammary cancer cells, causing inhibition of cancer migration and invasion. CONCLUSION: Two synthetic migrastatin analogues (MGSTA-5 and MGSTA-6 were shown to be promising compounds for inhibition of cancer metastasis. They may have beneficial therapeutic effects in cancer therapy in dogs, especially in combination with other anticancer drugs

  2. A novel peptide sansalvamide analogue inhibits pancreatic cancer cell growth through G0/G1 cell-cycle arrest

    International Nuclear Information System (INIS)

    Ujiki, Michael B.; Milam, Ben; Ding Xianzhong; Roginsky, Alexandra B.; Salabat, M. Reza; Talamonti, Mark S.; Bell, Richard H.; Gu Wenxin; Silverman, Richard B.; Adrian, Thomas E.

    2006-01-01

    Patients with pancreatic cancer have little hope for cure because no effective therapies are available. Sansalvamide A is a cyclic depsipeptide produced by a marine fungus. We investigated the effect of a novel sansalvamide A analogue on growth, cell-cycle phases, and induction of apoptosis in human pancreatic cancer cells in vitro. The sansalvamide analogue caused marked time- and concentration-dependent inhibition of DNA synthesis and cell proliferation of two human pancreatic cancer cell lines (AsPC-1 and S2-013). The analogue induced G0/G1 phase cell-cycle arrest and morphological changes suggesting induction of apoptosis. Apoptosis was confirmed by annexin V binding. This novel sansalvamide analogue inhibits growth of pancreatic cancer cells through G0/G1 arrest and induces apoptosis. Sansalvamide analogues may be valuable for the treatment of pancreatic cancer

  3. Eugenol and its synthetic analogues inhibit cell growth of human cancer cells (Part I)

    International Nuclear Information System (INIS)

    Carrasco A, H.; Cardona, W.; Espinoza C, L.; Gallardo, C.; Catalan M, K.; Cardile, V.; Lombardo, L.; Cuellar F, M.; Russo, A.

    2008-01-01

    Eugenol (4-allyl-2-methoxyphenol) (1) has been reported to possess antioxidant and anticancer properties. In an attempt to enhance intrinsic activity of this natural compound, some derivatives were synthesized. Eugenol was extracted from cloves oil and further, the eugenol analogues (2-6) were obtained through acetylation and nitration reactions. Eugenol (1) and its analogues (2-6) were examined by in vitro model of cancer using two human cancer cell lines: DU-145 (androgeninsensitive prostate cancer cells) and KB (oral squamous carcinoma cells). Cell viability, by tetrazolium salts assay, was measured. Lactic dehydrogenase (LDH) release was also investigated to evaluate the presence of cell toxicity as a result of cell disruption, subsequent to membrane rupture. In the examined cancer cells, all compounds showed cell-growth inhibition activity. The obtained results demonstrate that the compounds 5-allyl-3-nitrobenzene-1,2-diol (3) and 4-allyl- 2-methoxy-5-nitrophenyl acetate (5) were significantly (p 50 values in DU-145 cells of 19.02 x 10 -6 and 21.5 x 10 -6 mol L -1 , respectively, and in KB cells of 18.11 x 10 -6 and 21.26 x 10 -6 mol L -1 , respectively, suggesting that the presence of nitro and hydroxyl groups could be important in the activity of these compounds. In addition, our results seem to indicate that apoptotic cell demise appears to be induced in KB and DU-145 cells. In fact, in our experimental conditions, no statistically significant increase in LDH release was observed in cancer cells treated with eugenol and its analogues. (author)

  4. Eugenol and its synthetic analogues inhibit cell growth of human cancer cells (Part I)

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    Carrasco A, H.; Cardona, W. [Universidad Andres Bello, Vina del Mar (Chile). Dept. de Ciencias Quimicas]. E-mail: hcarrasco@unab.cl; Espinoza C, L.; Gallardo, C.; Catalan M, K. [Universidad Tecnica Federico Santa Maria, Valparaiso (Chile). Dept. de Quimica; Cardile, V.; Lombardo, L. [University of Catania (Italy). Dept. of Physiological Sciences; Cuellar F, M. [Universidad de Valparaiso (Chile). Facultad de Farmacia; Russo, A. [University of Catania (Italy). Dept. of Biological Chemistry, Medical Chemistry and Molecular Biology

    2008-07-01

    Eugenol (4-allyl-2-methoxyphenol) (1) has been reported to possess antioxidant and anticancer properties. In an attempt to enhance intrinsic activity of this natural compound, some derivatives were synthesized. Eugenol was extracted from cloves oil and further, the eugenol analogues (2-6) were obtained through acetylation and nitration reactions. Eugenol (1) and its analogues (2-6) were examined by in vitro model of cancer using two human cancer cell lines: DU-145 (androgeninsensitive prostate cancer cells) and KB (oral squamous carcinoma cells). Cell viability, by tetrazolium salts assay, was measured. Lactic dehydrogenase (LDH) release was also investigated to evaluate the presence of cell toxicity as a result of cell disruption, subsequent to membrane rupture. In the examined cancer cells, all compounds showed cell-growth inhibition activity. The obtained results demonstrate that the compounds 5-allyl-3-nitrobenzene-1,2-diol (3) and 4-allyl- 2-methoxy-5-nitrophenyl acetate (5) were significantly (p < 0,001) more active than eugenol, with IC{sub 50} values in DU-145 cells of 19.02 x 10{sup -6} and 21.5 x 10{sup -6} mol L{sup -1}, respectively, and in KB cells of 18.11 x 10{sup -6} and 21.26 x 10{sup -6} mol L{sup -1}, respectively, suggesting that the presence of nitro and hydroxyl groups could be important in the activity of these compounds. In addition, our results seem to indicate that apoptotic cell demise appears to be induced in KB and DU-145 cells. In fact, in our experimental conditions, no statistically significant increase in LDH release was observed in cancer cells treated with eugenol and its analogues. (author)

  5. New castanospermine glycoside analogues inhibit breast cancer cell proliferation and induce apoptosis without affecting normal cells.

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    Ghada Allan

    Full Text Available sp²-Iminosugar-type castanospermine analogues have been shown to exhibit anti-tumor activity. However, their effects on cell proliferation and apoptosis and the molecular mechanism at play are not fully understood. Here, we investigated the effect of two representatives, namely the pseudo-S- and C-octyl glycoside 2-oxa-3-oxocastanospermine derivatives SO-OCS and CO-OCS, on MCF-7 and MDA-MB-231 breast cancer and MCF-10A mammary normal cell lines. We found that SO-OCS and CO-OCS inhibited breast cancer cell viability in a concentration- and time-dependent manner. This effect is specific to breast cancer cells as both molecules had no impact on normal MCF-10A cell proliferation. Both drugs induced a cell cycle arrest. CO-OCS arrested cell cycle at G1 and G2/M in MCF-7 and MDA-MB-231 cells respectively. In MCF-7 cells, the G1 arrest is associated with a reduction of CDK4 (cyclin-dependent kinase 4, cyclin D1 and cyclin E expression, pRb phosphorylation, and an overexpression of p21(Waf1/Cip1. In MDA-MB-231 cells, CO-OCS reduced CDK1 but not cyclin B1 expression. SO-OCS accumulated cells in G2/M in both cell lines and this blockade was accompanied by a decrease of CDK1, but not cyclin B1 expression. Furthermore, both drugs induced apoptosis as demonstrated by the increased percentage of annexin V positive cells and Bax/Bcl-2 ratio. Interestingly, in normal MCF-10A cells the two drugs failed to modify cell proliferation, cell cycle progression, cyclins, or CDKs expression. These results demonstrate that the effect of CO-OCS and SO-OCS is triggered by both cell cycle arrest and apoptosis, suggesting that these castanospermine analogues may constitute potential anti-cancer agents against breast cancer.

  6. 1082-39, an analogue of sorafenib, inhibited human cancer cell growth more potently than sorafenib.

    Science.gov (United States)

    Chu, Jia-Hui; Zhao, Cui-Rong; Song, Zhi-Yu; Wang, Rui-Qi; Qin, Yi-Zhuo; Li, Wen-Bao; Qu, Xian-Jun

    2014-04-01

    1082-39, an analogue of sorafenib, is a derivative of indazole diarylurea. We evaluated the activity of 1082-39 against human cancer cell growth. Its effects and mechanisms of action were then compared with those of sorafenib. The experiments were performed in human melanoma M21 cells. Cell viability was estimated by using the colorimetric assay. Annexin V-FITC/PI staining assay was used to recognize the apoptotic cells. Further analysis of the mitochondria membrane potential (MMP) was performed by the JC-1 fluorescence probe staining. The levels of apoptotic proteins and kinases related to cancer proliferation were determined by western blotting assay. 1082-39 possessed the activity against cancer cell proliferation with time- and dose-dependent manner. 1082-39 induced M21 cell to apoptosis, showing the increase of annexin V-FITC/PI staining cells, the MMP collapse and releasing cytochrome c from mitochondria. Western blotting analysis showed the activation of the mitochondria-mediated intrinsic pathway, showing the increase of cleaved caspase-9, cleaved caspase-3 and cleaved PARP. Statistical analysis suggested that 1082-39 possessed greater activities than sorafenib in the inhibition of M21 proliferation and induction of apoptosis. These effects of 1082-39 might arise from its activity of regulation the PI3K/Akt and Wnt/β-catenin signaling pathways. 1082-39 is a promising candidate compound which could develop as a potent anticancer agent. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  7. Cell motility is inhibited by the antiepileptic compound, valproic acid and its teratogenic analogues

    DEFF Research Database (Denmark)

    Walmod, P S; Foley, A; Berezin, A

    1998-01-01

    -term recordings and measurements of mean-cell speed, the reduction in the motile behaviour was shown to correlate with the teratogenic potency of the tested compounds. The observed effects of VPA on cell motility was independent of the employed L-cell clone, and could be reproduced in cells containing...... the neuronal marker NCAM and in the neuronal cell line N2a. Furthermore, the observed effect was independent of culture substratum, being observed for L-cells grown on fibronectin as well as on plastic. Immunofluorescence microscopy revealed that VPA-treatment of mouse L-cells caused a redistribution of F...

  8. Resveratrol analogue 3,4,4′,5-tetramethoxystilbene inhibits growth, arrests cell cycle and induces apoptosis in ovarian SKOV‐3 and A-2780 cancer cells

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    Piotrowska, Hanna; Myszkowski, Krzysztof; Ziółkowska, Alicja [Department of Toxicology, Poznan University of Medical Sciences, Poznan (Poland); Kulcenty, Katarzyna [Chair of Medical Biotechnology, Poznan University of Medical Sciences, Poznan (Poland); Wierzchowski, Marcin [Department of Chemical Technology of Drugs, Poznan University of Medical Sciences, Poznan (Poland); Kaczmarek, Mariusz [Department of Clinical Immunology, Poznan University of Medical Sciences, Poznan (Poland); Murias, Marek [Department of Toxicology, Poznan University of Medical Sciences, Poznan (Poland); Kwiatkowska-Borowczyk, Eliza [Chair of Medical Biotechnology, Poznan University of Medical Sciences, Poznan (Poland); Department of Cancer Diagnostics and Immunology, Greater Poland Cancer Centre, Poznan (Poland); Jodynis-Liebert, Jadwiga, E-mail: liebert@ump.edu.pl [Department of Toxicology, Poznan University of Medical Sciences, Poznan (Poland)

    2012-08-15

    In the screening studies, cytotoxicity of 12 methylated resveratrol analogues on 11 human cancer cell lines was examined. The most active compound 3,4,4′5-tetramethoxystilbene (DMU-212) and two ovarian cancer cell lines A-2780 (IC{sub 50} = 0.71 μM) and SKOV-3 (IC{sub 50} = 11.51 μM) were selected for further investigation. To determine the mechanism of DMU-212 cytotoxicity, its ability to induce apoptosis was examined. DMU-212 arrested cell cycle in the G2/M or G0/G1 phase which resulted in apoptosis of both cell lines. The expression level of 84 apoptosis-related genes was investigated. In SKOV-3 cells DMU-212 caused up-regulation of pro-apoptotic Bax, Apaf-1 and p53 genes, specific to intrinsic pathway of apoptosis, and a decrease in Bcl-2 and Bcl 2110 mRNA expressions. Conversely, in A-2780 cells an increased expression of pro-apoptotic genes Fas, FasL, TNF, TNFRSF10A, TNFRSF21, TNFRSF16 specific to extracellular mechanism of apoptosis was observed. There are no data published so far regarding the receptor mediated apoptosis induced by DMU-212. The activation of caspase-3/7 was correlated with decreased TRAF-1 and BIRC-2 expression level in A-2780 cells exposed to DMU-212. DMU-212 caused a decrease in CYP1A1 and CYP1B1 mRNA levels in A-2780 by 50% and 75%, and in SKOV-3 cells by 15% and 45%, respectively. The protein expression was also reduced in both cell lines. It is noteworthy that the expression of CYP1B1 protein was entirely inhibited in A-2780 cells treated with DMU-212. It can be suggested that different CYP1B1 expression patterns in either ovarian cell line may affect their sensitivity to cytotoxic activity of DMU-212. -- Highlights: ► DMU-212 was the most cytotoxic among 12 O-methylated resveratrol analogues. ► DMU-212 arrested cell cycle at G2/M and G0/G1phase ► DMU-212 triggered mitochondria- and receptor‐mediated apoptosis. ► DMU-212 entirely inhibited CYP1B1 protein expression in A-2780 cells.

  9. Resveratrol analogue 3,4,4′,5-tetramethoxystilbene inhibits growth, arrests cell cycle and induces apoptosis in ovarian SKOV‐3 and A-2780 cancer cells

    International Nuclear Information System (INIS)

    Piotrowska, Hanna; Myszkowski, Krzysztof; Ziółkowska, Alicja; Kulcenty, Katarzyna; Wierzchowski, Marcin; Kaczmarek, Mariusz; Murias, Marek; Kwiatkowska-Borowczyk, Eliza; Jodynis-Liebert, Jadwiga

    2012-01-01

    In the screening studies, cytotoxicity of 12 methylated resveratrol analogues on 11 human cancer cell lines was examined. The most active compound 3,4,4′5-tetramethoxystilbene (DMU-212) and two ovarian cancer cell lines A-2780 (IC 50 = 0.71 μM) and SKOV-3 (IC 50 = 11.51 μM) were selected for further investigation. To determine the mechanism of DMU-212 cytotoxicity, its ability to induce apoptosis was examined. DMU-212 arrested cell cycle in the G2/M or G0/G1 phase which resulted in apoptosis of both cell lines. The expression level of 84 apoptosis-related genes was investigated. In SKOV-3 cells DMU-212 caused up-regulation of pro-apoptotic Bax, Apaf-1 and p53 genes, specific to intrinsic pathway of apoptosis, and a decrease in Bcl-2 and Bcl 2110 mRNA expressions. Conversely, in A-2780 cells an increased expression of pro-apoptotic genes Fas, FasL, TNF, TNFRSF10A, TNFRSF21, TNFRSF16 specific to extracellular mechanism of apoptosis was observed. There are no data published so far regarding the receptor mediated apoptosis induced by DMU-212. The activation of caspase-3/7 was correlated with decreased TRAF-1 and BIRC-2 expression level in A-2780 cells exposed to DMU-212. DMU-212 caused a decrease in CYP1A1 and CYP1B1 mRNA levels in A-2780 by 50% and 75%, and in SKOV-3 cells by 15% and 45%, respectively. The protein expression was also reduced in both cell lines. It is noteworthy that the expression of CYP1B1 protein was entirely inhibited in A-2780 cells treated with DMU-212. It can be suggested that different CYP1B1 expression patterns in either ovarian cell line may affect their sensitivity to cytotoxic activity of DMU-212. -- Highlights: ► DMU-212 was the most cytotoxic among 12 O-methylated resveratrol analogues. ► DMU-212 arrested cell cycle at G2/M and G0/G1phase ► DMU-212 triggered mitochondria- and receptor‐mediated apoptosis. ► DMU-212 entirely inhibited CYP1B1 protein expression in A-2780 cells.

  10. U-61,431F, a stable prostacyclin analogue, inhibits the proliferation of bovine vascular smooth muscle cells with little antiproliferative effect on endothelial cells

    International Nuclear Information System (INIS)

    Shirotani, M.; Yui, Y.; Hattori, R.; Kawai, C.

    1991-01-01

    The effects of U-61,431F, ciprostene, a stable prostacyclin analogue, were examined on the proliferation of cultured quiescent bovine aortic endothelial cells (EC) and smooth muscle cells (SMC). After stimulation with 5% fetal calf serum, U-61,431F suppressed both the DNA synthesis and proliferation of SMC dose-dependently at the concentration of 3-100 microM, but had no effect on either of them in EC at a concentration of up to 30 microM. The inhibitory effect on DNA synthesis was greater in SMC than in EC at 3-50 microM. When SMC were stimulated with platelet-derived growth factor (PDGF) for 2 hrs followed by a 22-hr incubation with insulin, U-61,431F (1-50 microM) administered at the time of PDGF stimulation did not inhibit DNA synthesis. SMC initiated and terminated DNA synthesis at about 15-18 h and 24 h after stimulation with serum, respectively. Inhibition of DNA synthesis in serum-stimulated SMC as a function of the addition time of U-61,431F reduced at 3-12 h after the stimulation. U-61,431F raised the cyclic AMP (cAMP) content in SMC. Moreover, a phosphodiesterase inhibitor, 3-isobutyl-1-methylxanthine, and a more specific cAMP phosphodiesterase inhibitor, Ro 20-1724, augmented the inhibition of DNA synthesis in SMC concomitant with further elevation of cAMP level. These results suggest that U-61,431F inhibits DNA synthesis of SMC acting in the progression stage rather than in the competence stage, with little antiproliferative effect on EC. cAMP may play an important role in its antiproliferative action in SMC

  11. Andrographolide Analogue Induces Apoptosis and Autophagy Mediated Cell Death in U937 Cells by Inhibition of PI3K/Akt/mTOR Pathway.

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    Deepak Kumar

    Full Text Available Current chemotherapeutic agents based on apoptosis induction are lacking in desired efficacy. Therefore, there is continuous effort to bring about new dimension in control and gradual eradication of cancer by means of ever evolving therapeutic strategies. Various forms of PCD are being increasingly implicated in anti-cancer therapy and the complex interplay among them is vital for the ultimate fate of proliferating cells. We elaborated and illustrated the underlying mechanism of the most potent Andrographolide analogue (AG-4 mediated action that involved the induction of dual modes of cell death-apoptosis and autophagy in human leukemic U937 cells.AG-4 induced cytotoxicity was associated with redox imbalance and apoptosis which involved mitochondrial depolarisation, altered apoptotic protein expressions, activation of the caspase cascade leading to cell cycle arrest. Incubation with caspase inhibitor Z-VAD-fmk or Bax siRNA decreased cytotoxic efficacy of AG-4 emphasising critical roles of caspase and Bax. In addition, AG-4 induced autophagy as evident from LC3-II accumulation, increased Atg protein expressions and autophagosome formation. Pre-treatment with 3-MA or Atg 5 siRNA suppressed the cytotoxic effect of AG-4 implying the pro-death role of autophagy. Furthermore, incubation with Z-VAD-fmk or Bax siRNA subdued AG-4 induced autophagy and pre-treatment with 3-MA or Atg 5 siRNA curbed AG-4 induced apoptosis-implying that apoptosis and autophagy acted as partners in the context of AG-4 mediated action. AG-4 also inhibited PI3K/Akt/mTOR pathway. Inhibition of mTOR or Akt augmented AG-4 induced apoptosis and autophagy signifying its crucial role in its mechanism of action.Thus, these findings prove the dual ability of AG-4 to induce apoptosis and autophagy which provide a new perspective to it as a potential molecule targeting PCD for future cancer therapeutics.

  12. Amino acid containing thapsigargin analogues deplete androgen receptor protein via synthesis inhibition and induce the death of prostate cancer cells

    DEFF Research Database (Denmark)

    Griend, Donald J Vander; Antony, Lizamma; Dalrymple, Susan L

    2009-01-01

    There are quantitative and/or qualitative mechanisms allowing androgen receptor (AR) growth signaling in androgen ablation refractory prostate cancer cells. Regardless of the mechanism, agents that deplete AR protein expression prevent such AR growth signaling. Thapsigargin (TG) is a highly cell......-penetrant sequiterpene-lactone that once inside cells inhibits (IC(50), approximately 10 nmol/L) critically important housekeeping SERCA 2b calcium pumps in the endoplasmic reticulum. Using a series of five genetically diverse androgen ablation refractory human prostate cancer lines (LNCaP, LAPC-4, VCaP, MDA-PCa-2b......-specific proteases, such as prostate-specific antigen and prostate-specific membrane antigen, or cancer-specific proteases, such as fibroblast activation protein, so that toxicity of these prodrugs is selectively targeted to metastatic sites of prostate cancer. Based on these results, these prodrugs are undergoing...

  13. Vitamin E analogues inhibit angiogenesis by selective induction of apoptosis in proliferating endothelial cells: the role of oxidative stress

    Czech Academy of Sciences Publication Activity Database

    Dong, L.F.; Swettenham, E.; Eliasson, J.; Wang, X. F.; Gold, M.; Medunic, Y.; Stantic, M.; Low, P.; Procházka, L.; Witting, P. K.; Turánek, J.; Akporiaye, E.T.; Ralph, S.J.; Neužil, Jiří

    2007-01-01

    Roč. 67, č. 24 (2007), s. 11906-11913 ISSN 0008-5472 R&D Projects: GA AV ČR KAN200520703; GA AV ČR IAA500520602 Institutional research plan: CEZ:AV0Z50520514; CEZ:AV0Z50520701 Keywords : mitocans * proliferating endothelial cells * apoptosis Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 7.672, year: 2007

  14. Differential Top10 promoter regulation by six tetracycline analogues in plant cells

    Science.gov (United States)

    Love, John; Allen, George C.; Gatz, Christiane; Thompson, William F.; Brown, C. S. (Principal Investigator)

    2002-01-01

    The effects of five tetracycline analogues, anhydrotetracycline, doxycycline, minocycline, oxytetracycline, and tetracycline, on Top10 promoter activity in NT1 tobacco tissue culture cells have been analysed. The concentration that repressed Top10 promoter activity, the level of transgene repression and the kinetics of transgene de-repression were determined for each analogue, and could not be predicted from in vitro binding affinity to the tetracycline repressor or from comparison with animal cells. Doxycycline had the most potent effect on the Top10 promoter and completely inhibited transgene expression at 4 nmol l(-1). Tetracycline was the most versatile of the analogues tested; tetracycline inhibited the Top10 promoter at 10 nmol l(-1) and was easily washed out to restore Top10-driven expression in 12-24 h. A study was also made of the suitability for plant research of a novel tetracycline analogue, GR33076X. In animal cells, GR33076X de-repressed Top10 promoter activity in the presence of inhibitory concentrations of anhydrotetracycline. In NT1, it is shown that GR 33076X can antagonize repression of the Top10 promoter in the presence of tetracycline, but not of anhydrotetracycline or of doxycycline. Different tetracycline analogues can therefore be used to regulate the Top10 promoter in plant cells and this property may be exploited in planning an optimum course of transgene regulation.

  15. Influence of prostaglandin analogues on epithelial cell proliferation and xenograft growth.

    Science.gov (United States)

    Tutton, P J; Barkla, D H

    1980-01-01

    The influence of two prostaglandin (PG) analogues, 16,16-dimethyl PG E2 and 16,16-dimethyl PG F2 alpha and of the cyclo-oxygenase inhibitor, flurbiprofen, on epithelial cell proliferation was assessed using a stathmokinetic technique. The epithelia examined were those of the jejunal crypts, the colonic crypts and that of dimethylhydrazine-induced adenocarcinomas of rat colon. The influence of the two prostaglandin analogues, and of flurbiprofen, on the growth of a human colorectal tumour propagated as xenografts in immune-deprived mice was also assessed. The PG E2 analogue transiently inhibited xenograft growth, but was without effect on the mitotic rate in the rat tissues. The PG F2 alpha analogue was also found to inhibit xenograft growth but, unlike the PG E2 analogue, it was found to be a strong inhibitor of cell proliferation in rat colonic tumours, and an accelerator of proliferation in jejunal-crypt cells. The only statistically significant effect of flurbiprofen was to accelerate cell division in the rat colonic tumours.

  16. The monoamine oxidase inhibition properties of selected structural analogues of methylene blue

    International Nuclear Information System (INIS)

    Delport, Anzelle; Harvey, Brian H.; Petzer, Anél; Petzer, Jacobus P.

    2017-01-01

    The thionine dye, methylene blue (MB), is a potent inhibitor of monoamine oxidase (MAO) A, a property that may, at least in part, mediate its antidepressant effects in humans and animals. The central inhibition of MAO-A by MB has also been linked to serotonin toxicity (ST) which may arise when MB is used in combination with serotonergic drugs. Structural analogues and the principal metabolite of MB, azure B, have also been reported to inhibit the MAO enzymes, with all compounds exhibiting specificity for the MAO-A isoform. To expand on the structure-activity relationships (SARs) of MAO inhibition by MB analogues, the present study investigates the human MAO inhibition properties of five MB analogues: neutral red, Nile blue, new methylene blue, cresyl violet and 1,9-dimethyl methylene blue. Similar to MB, these analogues also are specific MAO-A inhibitors with cresyl violet (IC 50 = 0.0037 μM), Nile blue (IC 50 = 0.0077 μM) and 1,9-dimethyl methylene blue (IC 50 = 0.018 μM) exhibiting higher potency inhibition compared to MB (IC 50 = 0.07 μM). Nile blue also represents a potent MAO-B inhibitor with an IC 50 value of 0.012 μM. From the results it may be concluded that non-thionine MB analogues (e.g. cresyl violet and Nile blue) also may exhibit potent MAO inhibition, a property which should be considered when using these compounds in pharmacological studies. Benzophenoxazines such as cresyl violet and Nile blue are, similar to phenothiazines (e.g. MB), representative of high potency MAO-A inhibitors with a potential risk of ST. - Highlights: • MB analogues, cresyl violet and Nile blue, are high potency MAO-A inhibitors. • Nile blue also represents a potent MAO-B inhibitor. • Potent MAO-A inhibition should alert to potential serotonin toxicity.

  17. Synthesis, anticancer activity, and inhibition of tubulin polymerization by conformationally restricted analogues of lavendustin A.

    Science.gov (United States)

    Mu, Fanrong; Hamel, Ernest; Lee, Debbie J; Pryor, Donald E; Cushman, Mark

    2003-04-24

    Compounds in the lavendustin A series have been shown to inhibit both protein-tyrosine kinases (PTKs) and tubulin polymerization. Since certain lavendustin A derivatives can exist in conformations that resemble both the trans-stilbene structure of the PTK inhibitor piceatannol and the cis-stilbene structure of the tubulin polymerization inhibitor combretastatin A-4, the possibility exists that the ratio of the two types of activities of the lavendustins could be influenced through the synthesis of conformationally restricted analogues. Accordingly, the benzylaniline structure of a series of pharmacologically active lavendustin A fragments was replaced by either their cis- or their trans-stilbene relatives, and effects on both inhibition of tubulin polymerization and cytotoxicity in cancer cell cultures were monitored. Both dihydrostilbene and 1,2-diphenylalkyne congeners were also prepared and evaluated biologically. Surprisingly, conformational restriction of the bridge between the two aromatic rings of the lavendustins had no significant effect on biological activity. On the other hand, conversion of the three phenolic hydroxyl groups of the lavendustin A derivatives to their corresponding methyl ethers consistently abolished their ability to inhibit tubulin polymerization and usually decreased cytotoxicity in cancer cell cultures as well, indicating the importance of at least one of the phenolic hydroxyl groups. Further investigation suggested that the phenolic hydroxyl group in the salicylamide ring was required for activity, while the two phenol moieties in the hydroquinone ring could be methylated with retention of activity. Two of the lavendustin A derivatives displayed IC(50) values of 1.4 microM for inhibition of tubulin polymerization, which ranks them among the most potent of the known tubulin polymerization inhibitors.

  18. Inhibition of food stimulated acid secretion by misoprostol, an orally active synthetic E1 analogue prostaglandin.

    OpenAIRE

    Ramage, J K; Denton, A; Williams, J G

    1985-01-01

    The effect of 200 micrograms misoprostol (a synthetic prostaglandin E1 analogue) on food stimulated intragastric acidity has been monitored over a 9 h period in 16 normal volunteers. Misoprostol caused a significant inhibition of intragastric acidity for 2 h post-dosing, but no significant effect was seen thereafter on either basal or food stimulated acidity.

  19. Nucleoside analogue 2’-C-methylcytidine inhibits hepatitis E virus replication but antagonizes ribavirin

    NARCIS (Netherlands)

    Qu, C. (Changbo); L. Xu (Lei); Y. Yin (Yuebang); M.P. Peppelenbosch (Maikel); Q. Pan (Qiuwei); W. Wang (Wenshi)

    2017-01-01

    textabstractHepatitis E virus (HEV) infection has emerged as a global health issue, but no approved medication is available. The nucleoside analogue 2’-C-methylcytidine (2CMC), a viral polymerase inhibitor, has been shown to inhibit infection with a variety of viruses, including hepatitis C virus

  20. Plumbagin, a vitamin K3 analogue ameliorate malaria pathogenesis by inhibiting oxidative stress and inflammation.

    Science.gov (United States)

    Gupta, Amit Chand; Mohanty, Shilpa; Saxena, Archana; Maurya, Anil Kumar; Bawankule, Dnyaneshwar U

    2018-03-22

    Plumbagin, a vitamin K3 analogue is the major active constituent in several plants including root of Plumbago indica Linn. This compound has been shown to exhibit a wide spectrum of pharmacological activities. The present investigation was to evaluate the ameliorative effects of plumbagin (PL) against severe malaria pathogenesis due to involvement of oxidative stress and inflammatory response in Plasmodium berghei infected malaria in mice. Malaria pathogenesis was induced by intra-peritoneal injection of P. berghei infected red blood cells into the Swiss albino mice. PL was administered orally at doses of 3, 10 and 30 mg/kg/day following Peter's 4 day suppression test. Oral administration of PL showed significant reduction of parasitaemia and increase in mean survival time. PL treatment is also attributed to significant increase in the blood glucose and haemoglobin level when compared with vehicle-treated infected mice. Significant inhibition in level of oxidative stress and pro-inflammation related markers were observed in PL treated group. The trend of inhibition in oxidative stress markers level after oral treatment of PL was MPO > LPO > ROS in organ injury in P. berghei infected mice. This study showed that plumbagin is able to ameliorate malaria pathogenesis by augmenting anti-oxidative and anti-inflammatory mechanism apart from its effect on reducing parasitaemia and increasing mean survival time of malaria-induced mice.

  1. Opposite responses of rabbit and human globin mRNAs to translational inhibition by cap analogues

    International Nuclear Information System (INIS)

    Shakin, S.H.; Liebhaber, S.A.

    1987-01-01

    The translational efficiency of an mRNA may be determined at the step of translational initiation by the efficiency of its interaction with the cap binding protein complex. To further investigate the role of these interactions in translational control, the authors compare in vitro the relative sensitivities of rabbit and human α- and β-globin mRNAs to translational inhibition by cap analogues. They find that rabbit β-globin mRNA is more resistant to translational inhibition by cap analogues than rabbit α-globin mRNA, while in contrast, human β-globin mRNA is more sensitive to cap analogue inhibition than human α- and β-globin mRNAs is unexpected as direct in vivo and in vitro comparisons of polysome profiles reveal parallel translational handling of the α- and β-globin mRNAs from these two species. This discordance between the relative translational sensitivities of these mRNAs to cap analogues and their relative ribosome loading activities suggests that cap-dependent events may not be rate limiting in steady-state globin translation

  2. Synthetic Strigolactone Analogues Reveal Anti-Cancer Activities on Hepatocellular Carcinoma Cells

    KAUST Repository

    Hasan, Mohammed Nihal

    2018-02-09

    Hepatocellular carcinoma (HCC) remains one of the leading causes of death worldwide. The complex etiology is attributed to many factors like heredity, cirrhosis, hepatitis infections or the dysregulation of the different molecular pathways. Nevertheless, the current treatment regimens have either severe side effects or tumors gradually acquire resistance upon prolonged use. Thus, developing a new selective treatment for HCC is the need of the hour. Many anticancer agents derived from plants have been evaluated for their cytotoxicity towards many human cancer cell lines. Strigolactones (SLs)-a newly discovered class of phytohormones, play a crucial role in the development of plant-root and shoot. Recently, many synthetic analogues of SLs have demonstrated pro-apoptotic effects on different cancer cell lines like prostate, breast, colon and lung. In this study, we tested synthetic SLs analogues on HCC cell line-HepG2 and evaluated their capability to induce cell proliferation inhibition and apoptosis. Primary WST-1 assays, followed by annexin-V/7AAD staining, demonstrated the anti-proliferative effects. The SLs analogues TIT3 and TIT7 were found to significantly reduce HepG2 cell viability in a dose- and time-dependent manner and induce apoptosis. Interestingly, though TIT3 and TIT7 strongly affected cancer cell proliferation, both compounds showed moderate anti-proliferative effect on normal cells. Further, migration of cancer cells was suppressed upon treatment with TIT3 and TIT7 in a wound healing assay. In summary, these findings suggest that two SLs analogues TIT3 and TIT7 exert selective inhibitory effects on cancer cells most likely through targeting microtubules. SLs analogues could be used in future as potential anti-cancer candidates in chemotherapy.

  3. Synthetic Strigolactone Analogues Reveal Anti-Cancer Activities on Hepatocellular Carcinoma Cells

    KAUST Repository

    Hasan, Mohammed Nihal; Choudhry, Hani; Razvi, Syed Shoeb; Moselhy, Said Salama; Kumosani, Taha Abduallah; Zamzami, Mazin A.; Omran, Ziad; Halwani, Majed A.; Al-Babili, Salim; Abualnaja, Khalid Omer; Al-Malki, Abdulrahman Labeed; Alhosin, Mahmoud; Asami, Tadao

    2018-01-01

    Hepatocellular carcinoma (HCC) remains one of the leading causes of death worldwide. The complex etiology is attributed to many factors like heredity, cirrhosis, hepatitis infections or the dysregulation of the different molecular pathways. Nevertheless, the current treatment regimens have either severe side effects or tumors gradually acquire resistance upon prolonged use. Thus, developing a new selective treatment for HCC is the need of the hour. Many anticancer agents derived from plants have been evaluated for their cytotoxicity towards many human cancer cell lines. Strigolactones (SLs)-a newly discovered class of phytohormones, play a crucial role in the development of plant-root and shoot. Recently, many synthetic analogues of SLs have demonstrated pro-apoptotic effects on different cancer cell lines like prostate, breast, colon and lung. In this study, we tested synthetic SLs analogues on HCC cell line-HepG2 and evaluated their capability to induce cell proliferation inhibition and apoptosis. Primary WST-1 assays, followed by annexin-V/7AAD staining, demonstrated the anti-proliferative effects. The SLs analogues TIT3 and TIT7 were found to significantly reduce HepG2 cell viability in a dose- and time-dependent manner and induce apoptosis. Interestingly, though TIT3 and TIT7 strongly affected cancer cell proliferation, both compounds showed moderate anti-proliferative effect on normal cells. Further, migration of cancer cells was suppressed upon treatment with TIT3 and TIT7 in a wound healing assay. In summary, these findings suggest that two SLs analogues TIT3 and TIT7 exert selective inhibitory effects on cancer cells most likely through targeting microtubules. SLs analogues could be used in future as potential anti-cancer candidates in chemotherapy.

  4. The monoamine oxidase inhibition properties of selected structural analogues of methylene blue

    Energy Technology Data Exchange (ETDEWEB)

    Delport, Anzelle [Pharmaceutical Chemistry, School of Pharmacy, North-West University, Private Bag X6001, Potchefstroom 2520 (South Africa); Centre of Excellence for Pharmaceutical Sciences, North-West University, Private Bag X6001, Potchefstroom 2520 (South Africa); Harvey, Brian H. [Centre of Excellence for Pharmaceutical Sciences, North-West University, Private Bag X6001, Potchefstroom 2520 (South Africa); Pharmacology, School of Pharmacy, North-West University, Private Bag X6001, Potchefstroom 2520 (South Africa); Petzer, Anél [Pharmaceutical Chemistry, School of Pharmacy, North-West University, Private Bag X6001, Potchefstroom 2520 (South Africa); Centre of Excellence for Pharmaceutical Sciences, North-West University, Private Bag X6001, Potchefstroom 2520 (South Africa); Petzer, Jacobus P., E-mail: jacques.petzer@nwu.ac.za [Pharmaceutical Chemistry, School of Pharmacy, North-West University, Private Bag X6001, Potchefstroom 2520 (South Africa); Centre of Excellence for Pharmaceutical Sciences, North-West University, Private Bag X6001, Potchefstroom 2520 (South Africa)

    2017-06-15

    The thionine dye, methylene blue (MB), is a potent inhibitor of monoamine oxidase (MAO) A, a property that may, at least in part, mediate its antidepressant effects in humans and animals. The central inhibition of MAO-A by MB has also been linked to serotonin toxicity (ST) which may arise when MB is used in combination with serotonergic drugs. Structural analogues and the principal metabolite of MB, azure B, have also been reported to inhibit the MAO enzymes, with all compounds exhibiting specificity for the MAO-A isoform. To expand on the structure-activity relationships (SARs) of MAO inhibition by MB analogues, the present study investigates the human MAO inhibition properties of five MB analogues: neutral red, Nile blue, new methylene blue, cresyl violet and 1,9-dimethyl methylene blue. Similar to MB, these analogues also are specific MAO-A inhibitors with cresyl violet (IC{sub 50} = 0.0037 μM), Nile blue (IC{sub 50} = 0.0077 μM) and 1,9-dimethyl methylene blue (IC{sub 50} = 0.018 μM) exhibiting higher potency inhibition compared to MB (IC{sub 50} = 0.07 μM). Nile blue also represents a potent MAO-B inhibitor with an IC{sub 50} value of 0.012 μM. From the results it may be concluded that non-thionine MB analogues (e.g. cresyl violet and Nile blue) also may exhibit potent MAO inhibition, a property which should be considered when using these compounds in pharmacological studies. Benzophenoxazines such as cresyl violet and Nile blue are, similar to phenothiazines (e.g. MB), representative of high potency MAO-A inhibitors with a potential risk of ST. - Highlights: • MB analogues, cresyl violet and Nile blue, are high potency MAO-A inhibitors. • Nile blue also represents a potent MAO-B inhibitor. • Potent MAO-A inhibition should alert to potential serotonin toxicity.

  5. Novel agmatine analogue, γ-guanidinooxypropylamine (GAPA) efficiently inhibits proliferation of Leishmania donovani by depletion of intracellular polyamine levels

    International Nuclear Information System (INIS)

    Singh, Sushma; Jhingran, Anupam; Sharma, Ankur; Simonian, Alina R.; Soininen, Pasi; Vepsalainen, Jouko; Khomutov, Alex R.; Madhubala, Rentala

    2008-01-01

    The efficacy of γ-guanidinooxypropylamine (GAPA), a novel agmatine analogue against protozoan parasite, Leishmaniadonovani was evaluated. Wild-type and ornithine decarboxylase-overexpressors of L. donovani were used to study the effect and mode of action of this inhibitor. GAPA inhibited the growth of both promastigotes and amastigotes. Ornithine decarboxylase (ODC) activity and polyamine levels were markedly lower in cells treated with GAPA and proliferation was rescued by addition of putrescine or spermidine. GAPA inhibited L. donovani recombinant ODC with K i value of ∼60 μM. The ODC-overexpressors showed significant resistance to GAPA. GAPA has pK a 6.71 and at physiological pH the analogue can mimic protonated state of putrescine and can probably use putrescine transport system. Transport of putrescine in wild-type L. donovani promastigotes was inhibited by GAPA. We for the first time report that GAPA is a potential antileishmanial lead compound and it possibly inhibits L. donovani growth by depletion of intracellular polyamine levels

  6. Lobatamide C: total synthesis, stereochemical assignment, preparation of simplified analogues, and V-ATPase inhibition studies.

    Science.gov (United States)

    Shen, Ruichao; Lin, Cheng Ting; Bowman, Emma Jean; Bowman, Barry J; Porco, John A

    2003-07-02

    The total synthesis and stereochemical assignment of the potent antitumor macrolide lobatamide C, as well as synthesis of simplified lobatamide analogues, is reported. Cu(I)-mediated enamide formation methodology has been developed to prepare the highly unsaturated enamide side chain of the natural product and analogues. A key fragment coupling employs base-mediated esterification of a beta-hydroxy acid and a salicylate cyanomethyl ester. Three additional stereoisomers of lobatamide C have been prepared using related synthetic routes. The stereochemistry at C8, C11, and C15 of lobatamide C was assigned by comparison of stereoisomers and X-ray analysis of a crystalline derivative. Synthetic lobatamide C, stereoisomers, and simplified analogues have been evaluated for inhibition of bovine chromaffin granule membrane V-ATPase. The salicylate phenol, enamide NH, and ortho-substitution of the salicylate ester have been shown to be important for V-ATPase inhibitory activity.

  7. 20(S)-Protopanaxadiol (PPD) analogues chemosensitize multidrug-resistant cancer cells to clinical anticancer drugs.

    Science.gov (United States)

    Liu, Junhua; Wang, Xu; Liu, Peng; Deng, Rongxin; Lei, Min; Chen, Wantao; Hu, Lihong

    2013-07-15

    Novel 20(S)-protopanoxadiol (PPD) analogues were designed, synthesized, and evaluated for the chemosensitizing activity against a multidrug resistant (MDR) cell line (KBvcr) overexpressing P-glycoprotein (P-gp). Structure-activity relationship analysis showed that aromatic substituted aliphatic amine at the 24-positions (groups V) effectively and significantly sensitized P-gp overexpressing multidrug resistant (MDR) cells to anticancer drugs, such as docetaxel (DOC), vincristine (VCR), and adriamycin (ADM). PPD derivatives 12 and 18 showed 1.3-2.6 times more effective reversal ability than verapamil (VER) for DOC and VCR. Importantly, no cytotoxicity was observed by the active PPD analogues (5μM) against both non-MDR and MDR cells, suggesting that PPD analogues serve as novel lead compounds toward a potent and safe resistance modulator. Moreover, a preliminary mechanism study demonstrated that the chemosensitizing activity of PPD analogues results from inhibition of P-glycoprotein (P-gp) overexpressed in MDR cancer cells. Copyright © 2013 The Authors. Published by Elsevier Ltd.. All rights reserved.

  8. Sulphamoylated 2-methoxyestradiol analogues induce apoptosis in adenocarcinoma cell lines.

    Directory of Open Access Journals (Sweden)

    Michelle Visagie

    Full Text Available 2-Methoxyestradiol (2ME2 is a naturally occurring estradiol metabolite which possesses antiproliferative, antiangiogenic and antitumor properties. However, due to its limited biological accessibility, synthetic analogues have been synthesized and tested in attempt to develop drugs with improved oral bioavailability and efficacy. The aim of this study was to evaluate the antiproliferative effects of three novel in silico-designed sulphamoylated 2ME2 analogues on the HeLa cervical adenocarcinoma cell line and estrogen receptor-negative breast adenocarcinoma MDA-MB-231 cells. A dose-dependent study (0.1-25 μM was conducted with an exposure time of 24 hours. Results obtained from crystal violet staining indicated that 0.5 μM of all 3 compounds reduced the number of cells to 50%. Lactate dehydrogenase assay was used to assess cytotoxicity, while the mitotracker mitochondrial assay and caspase-6 and -8 activity assays were used to investigate the possible occurrence of apoptosis. Tubulin polymerization assays were conducted to evaluate the influence of these sulphamoylated 2ME2 analogues on tubulin dynamics. Double immunofluorescence microscopy using labeled antibodies specific to tyrosinate and detyrosinated tubulin was conducted to assess the effect of the 2ME2 analogues on tubulin dynamics. An insignificant increase in the level of lactate dehydrogenase release was observed in the compounds-treated cells. These sulphamoylated compounds caused a reduction in mitochondrial membrane potential, cytochrome c release and caspase 3 activation indicating apoptosis induction by means of the intrinsic pathway in HeLa and MDA-MB-231 cells. Microtubule depolymerization was observed after exposure to these three sulphamoylated analogues.

  9. Gonadotropin-releasing hormone analogues inhibit leiomyoma extracellular matrix despite presence of gonadal hormones.

    Science.gov (United States)

    Malik, Minnie; Britten, Joy; Cox, Jeris; Patel, Amrita; Catherino, William H

    2016-01-01

    To determine the effect of GnRH analogues (GnRH-a) leuprolide acetate (LA) and cetrorelix acetate on gonadal hormone-regulated expression of extracellular matrix in uterine leiomyoma three-dimensional (3D) cultures. Laboratory study. University research laboratory. Women undergoing hysterectomy for symptomatic leiomyomas. The 3D cell cultures, protein analysis, Western blot, immunohistochemistry. Expression of extracellular matrix proteins, collagen 1, fibronectin, and versican in leiomyoma cells 3D cultures exposed to E2, P, LA, cetrorelix acetate, and combinations for 24- and 72-hour time points. The 3D leiomyoma cultures exposed to E2 for 24 hours demonstrated an increased expression of collagen-1 and fibronectin, which was maintained for up to 72 hours, a time point at which versican was up-regulated significantly. Although P up-regulated collagen-1 protein (1.29 ± 0.04) within 24 hours of exposure, significant increase in all extracellular matrix (ECM) proteins was observed when the gonadal hormones were used concomitantly. Significant decrease in the amount of ECM proteins was observed on use of GnRH-a, LA and cetrorelix, with 24-hour exposure. Both the compounds also significantly decreased ECM protein concentration despite the presence of E2 or both gonadal hormones. This study demonstrates that GnRH-a directly affect the gonadal hormone-regulated collagen-1, fibronectin, and versican production in their presence. These findings suggest that localized therapy with GnRH-a may inhibit leiomyoma growth even in the presence of endogenous gonadal hormone exposure, thereby providing a mechanism to eliminate the hypoestrogenic side effects associated with GnRH-a therapy. Published by Elsevier Inc.

  10. Sulforaphane Analogues with Heterocyclic Moieties: Syntheses and Inhibitory Activities against Cancer Cell Lines

    Directory of Open Access Journals (Sweden)

    Ye-Hui Shi

    2016-04-01

    Full Text Available Recent studies have shown that sulforaphane (SFN selectively inhibits the growth of ALDH+ breast cancer stem-like cells.Herein, a series of SFN analogues were synthesized and evaluated against breast cancer cell lines MCF-7 and SUM-159, and the leukemia stem cell-like cell line KG-1a. These SFN analogues were characterized by the replacement of the methyl group with heterocyclic moieties, and the replacement of the sulfoxide group with sulfide or sulfone. A growth inhibitory assay indicated that the tetrazole analogs 3d, 8d and 9d were significantly more potent than SFN against the three cancer cell lines. Compound 14c, the water soluble derivative of tetrazole sulfide 3d, demonstrated higher potency against KG-1a cell line than 3d. SFN, 3d and 14c significantly induced the activation of caspase-3, and reduced the ALDH+ subpopulation in the SUM159 cell line, while the marketed drug doxrubicin(DOX increased the ALDH+ subpopulation.

  11. New structural analogues of curcumin exhibit potent growth suppressive activity in human colorectal carcinoma cells

    International Nuclear Information System (INIS)

    Cen, Ling; Hutzen, Brian; Ball, Sarah; DeAngelis, Stephanie; Chen, Chun-Liang; Fuchs, James R; Li, Chenglong; Li, Pui-Kai; Lin, Jiayuh

    2009-01-01

    Colorectal carcinoma is one of the major causes of morbidity and mortality in the Western World. Novel therapeutic approaches are needed for colorectal carcinoma. Curcumin, the active component and yellow pigment of turmeric, has been reported to have several anti-cancer activities including anti-proliferation, anti-invasion, and anti-angiogenesis. Clinical trials have suggested that curcumin may serve as a potential preventive or therapeutic agent for colorectal cancer. We compared the inhibitory effects of curcumin and novel structural analogues, GO-Y030, FLLL-11, and FLLL-12, in three independent human colorectal cancer cell lines, SW480, HT-29, and HCT116. MTT cell viability assay was used to examine the cell viability/proliferation and western blots were used to determine the level of PARP cleavages. Half-Maximal inhibitory concentrations (IC 50 ) were calculated using Sigma Plot 9.0 software. Curcumin inhibited cell viability in all three of the human colorectal cancer cell lines studied with IC 50 values ranging between 10.26 μM and 13.31 μM. GO-Y030, FLLL-11, and FLLL-12 were more potent than curcumin in the inhibition of cell viability in these three human colorectal cancer cell lines with IC 50 values ranging between 0.51 μM and 4.48 μM. In addition, FLLL-11 and FLLL-12 exhibit low toxicity to WI-38 normal human lung fibroblasts with an IC-50 value greater than 1,000 μM. GO-Y030, FLLL-11, and FLLL-12 are also more potent than curcumin in the induction of apoptosis, as evidenced by cleaved PARP and cleaved caspase-3 in all three human colorectal cancer cell lines studied. The results indicate that the three curcumin analogues studied exhibit more potent inhibitory activity than curcumin in human colorectal cancer cells. Thus, they may have translational potential as chemopreventive or therapeutic agents for colorectal carcinoma

  12. A systems analysis of the chemosensitivity of breast cancer cells to the polyamine analogue PG-11047

    Energy Technology Data Exchange (ETDEWEB)

    Kuo, Wen-Lin; Das, Debopriya; Ziyad, Safiyyah; Bhattacharya, Sanchita; Gibb, William J.; Heiser, Laura M.; Sadanandam, Anguraj; Fontenay, Gerald V.; Hu, Zhi; Wang, Nicholas J.; Bayani, Nora; Feiler, Heidi S.; Neve, Richard M.; Wyrobek, Andrew J.; Spellman, Paul T.; Marton, Laurence J.; Gray, Joe W.

    2009-11-14

    Polyamines regulate important cellular functions and polyamine dysregulation frequently occurs in cancer. The objective of this study was to use a systems approach to study the relative effects of PG-11047, a polyamine analogue, across breast cancer cells derived from different patients and to identify genetic markers associated with differential cytotoxicity. A panel of 48 breast cell lines that mirror many transcriptional and genomic features present in primary human breast tumours were used to study the antiproliferative activity of PG-11047. Sensitive cell lines were further examined for cell cycle distribution and apoptotic response. Cell line responses, quantified by the GI50 (dose required for 50% relative growth inhibition) were correlated with the omic profiles of the cell lines to identify markers that predict response and cellular functions associated with drug sensitivity. The concentrations of PG-11047 needed to inhibit growth of members of the panel of breast cell lines varied over a wide range, with basal-like cell lines being inhibited at lower concentrations than the luminal cell lines. Sensitive cell lines showed a significant decrease in S phase fraction at doses that produced little apoptosis. Correlation of the GI50 values with the omic profiles of the cell lines identified genomic, transcriptional and proteomic variables associated with response. A 13-gene transcriptional marker set was developed as a predictor of response to PG-11047 that warrants clinical evaluation. Analyses of the pathways, networks and genes associated with response to PG-11047 suggest that response may be influenced by interferon signaling and differential inhibition of aspects of motility and epithelial to mesenchymal transition.

  13. A systems analysis of the chemosensitivity of breast cancer cells to the polyamine analogue PG-11047

    Directory of Open Access Journals (Sweden)

    Feiler Heidi S

    2009-12-01

    Full Text Available Abstract Background Polyamines regulate important cellular functions and polyamine dysregulation frequently occurs in cancer. The objective of this study was to use a systems approach to study the relative effects of PG-11047, a polyamine analogue, across breast cancer cells derived from different patients and to identify genetic markers associated with differential cytotoxicity. Methods A panel of 48 breast cell lines that mirror many transcriptional and genomic features present in primary human breast tumours were used to study the antiproliferative activity of PG-11047. Sensitive cell lines were further examined for cell cycle distribution and apoptotic response. Cell line responses, quantified by the GI50 (dose required for 50% relative growth inhibition were correlated with the omic profiles of the cell lines to identify markers that predict response and cellular functions associated with drug sensitivity. Results The concentrations of PG-11047 needed to inhibit growth of members of the panel of breast cell lines varied over a wide range, with basal-like cell lines being inhibited at lower concentrations than the luminal cell lines. Sensitive cell lines showed a significant decrease in S phase fraction at doses that produced little apoptosis. Correlation of the GI50 values with the omic profiles of the cell lines identified genomic, transcriptional and proteomic variables associated with response. Conclusions A 13-gene transcriptional marker set was developed as a predictor of response to PG-11047 that warrants clinical evaluation. Analyses of the pathways, networks and genes associated with response to PG-11047 suggest that response may be influenced by interferon signalling and differential inhibition of aspects of motility and epithelial to mesenchymal transition. See the related commentary by Benes and Settleman: http://www.biomedcentral.com/1741-7015/7/78

  14. Cytostatic versus cytocidal activities of chloroquine analogues and inhibition of hemozoin crystal growth.

    Science.gov (United States)

    Gorka, Alexander P; Alumasa, John N; Sherlach, Katy S; Jacobs, Lauren M; Nickley, Katherine B; Brower, Jonathan P; de Dios, Angel C; Roepe, Paul D

    2013-01-01

    We report an improved, nonhazardous, high-throughput assay for in vitro quantification of antimalarial drug inhibition of β-hematin (hemozoin) crystallization performed under conditions that are more physiological relative to previous assays. The assay uses the differential detergent solubility of crystalline and noncrystalline forms of heme and is optimized via the use of lipid catalyst. Using this assay, we quantify the effect of pH on the crystal growth-inhibitory activities of current quinoline antimalarials, evaluate the catalytic efficiencies of different lipids, and test for a possible correlation between hemozoin inhibition by drugs versus their antiplasmodial activity. Consistent with several previous reports, we found a good correlation between hemozoin inhibition potency versus cytostatic antiplasmodial potency (50% inhibitory concentration) for a series of chloroquine (CQ) analogues. However, we found no correlation between hemozoin inhibition potency and cytocidal antiplasmodial potency (50% lethal dose) for the same drugs, suggesting that cellular targets for these two layers of 4-aminoquinoline drug activity differ. This important concept is also explored further for QN and its stereoisomers in the accompanying paper (A. P. Gorka, K. S. Sherlach, A. C. de Dios, and P. D. Roepe, Antimicrob. Agents Chemother. 57:365-374, 2013).

  15. Inhibition of platelet aggregation by tartrazine and a pyrazolone analogue in normal and allergic individuals.

    Science.gov (United States)

    Gallagher, J S; Splansky, G L; Bernstein, I L

    1980-11-01

    The effect of tartrazine (T) (yellow dye No. 5) and one of its metabolites an aminopyrazolone analogue (1-sulphophenyl-3-carboxy-5-hydroxypyrazole, SCHP) upon collagen-induced platelet aggregation (C-PA) was investigated in fourteen atopic patients and fourteen normal subjects. Both T and SCHP inhibited C-PA in atopic patients at significantly lower doses than in normal volunteers. The mean inhibitory concentrations of SCHP were similar to aspirin in both atopic and normal individuals. Although the precise mechanism by which these chemicals block C-PA has not been elucidated, this in vitro system may be a useful method of assessing non-immune mechanisms involved in reactions to tartrazine.

  16. Structural, Biochemical, and Computational Studies Reveal the Mechanism of Selective Aldehyde Dehydrogenase 1A1 Inhibition by Cytotoxic Duocarmycin Analogues.

    Science.gov (United States)

    Koch, Maximilian F; Harteis, Sabrina; Blank, Iris D; Pestel, Galina; Tietze, Lutz F; Ochsenfeld, Christian; Schneider, Sabine; Sieber, Stephan A

    2015-11-09

    Analogues of the natural product duocarmycin bearing an indole moiety were shown to bind aldehyde dehydrogenase 1A1 (ALDH1A1) in addition to DNA, while derivatives without the indole solely addressed the ALDH1A1 protein. The molecular mechanism of selective ALDH1A1 inhibition by duocarmycin analogues was unraveled through cocrystallization, mutational studies, and molecular dynamics simulations. The structure of the complex shows the compound embedded in a hydrophobic pocket, where it is stabilized by several crucial π-stacking and van der Waals interactions. This binding mode positions the cyclopropyl electrophile for nucleophilic attack by the noncatalytic residue Cys302, thereby resulting in covalent attachment, steric occlusion of the active site, and inhibition of catalysis. The selectivity of duocarmycin analogues for ALDH1A1 is unique, since only minor alterations in the sequence of closely related protein isoforms restrict compound accessibility. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Synthesis, Characterization and In Vitro Anticancer Activity of C-5 Curcumin Analogues with Potential to Inhibit TNF-α-Induced NF-κB Activation

    Directory of Open Access Journals (Sweden)

    Amit Anthwal

    2014-01-01

    Full Text Available In a search of new compounds active against cancer, synthesis of a series of C-5 curcumin analogues was carried out. The new compounds demonstrated good cytotoxicity against chronic myeloid leukemia (KBM5 and colon cancer (HCT116 cell lines. Further, these compounds were found to have better potential to inhibit TNF-α-induced NF-κB activation in comparison to curcumin, which show their potential to act as anti-inflammatory agents. Some compounds were found to show higher cytotoxicity against cancer cell lines in comparison to curcumin used as standard.

  18. Curcumin and Its Analogue Induce Apoptosis in Leukemia Cells and Have Additive Effects with Bortezomib in Cellular and Xenograft Models

    Directory of Open Access Journals (Sweden)

    L. I. Nagy

    2015-01-01

    Full Text Available Combination therapy of bortezomib with other chemotherapeutics is an emerging treatment strategy. Since both curcumin and bortezomib inhibit NF-κB, we tested the effects of their combination on leukemia cells. To improve potency, a novel Mannich-type curcumin derivative, C-150, was synthesized. Curcumin and its analogue showed potent antiproliferative and apoptotic effects on the human leukemia cell line, HL60, with different potency but similar additive properties with bortezomib. Additive antiproliferative effects were correlated well with LPS-induced NF-κB inhibition results. Gene expression data on cell cycle and apoptosis related genes, obtained by high-throughput QPCR, showed that curcumin and its analogue act through similar signaling pathways. In correlation with in vitro results similar additive effect could be obsereved in SCID mice inoculated systemically with HL60 cells. C-150 in a liposomal formulation given intravenously in combination with bortezomib was more efficient than either of the drugs alone. As our novel curcumin analogue exerted anticancer effects in leukemic cells at submicromolar concentration in vitro and at 3 mg/kg dose in vivo, which was potentiated by bortezomib, it holds a great promise as a future therapeutic agent in the treatment of leukemia alone or in combination.

  19. The fungal phytotoxin alternariol 9-methyl ether and some of its synthetic analogues inhibit the photosynthetic electron transport chain.

    Science.gov (United States)

    Demuner, Antonio Jacinto; Barbosa, Luiz Cláudio Almeida; Miranda, Ana Cristina Mendes; Geraldo, Guilherme Carvalho; da Silva, Cleiton Moreira; Giberti, Samuele; Bertazzini, Michele; Forlani, Giuseppe

    2013-12-27

    Alternariol and monomethylalternariol are natural phytotoxins produced by some fungal strains, such as Nimbya and Alternaria. These substances confer virulence to phytopathogens, yet no information is available concerning their mode of action. Here we show that in the micromolar range alternariol 9-methyl ether is able to inhibit the electron transport chain (IC50 = 29.1 ± 6.5 μM) in isolated spinach chloroplasts. Since its effectiveness is limited by poor solubility in water, several alternariol analogues were synthesized using different aromatic aldehydes. The synthesized 6H-benzo[c]cromen-6-ones, 5H-chromene[4,3-b]pyridin-5-one, and 5H-chromene[4,3-c]pyridin-5-one also showed inhibitory properties, and three 6H-benzo[c]cromen-6-ones were more effective (IC50 = 12.8-22.8 μM) than the lead compound. Their addition to the culture medium of a cyanobacterial model strain was found to inhibit algal growth, with a relative effectiveness that was consistent with their activity in vitro. In contrast, the growth of a nonphotosynthetic plant cell culture was poorly affected. These compounds may represent a novel lead for the development of new active principles targeting photosynthesis.

  20. The effects of humanin and its analogues on male germ cell apoptosis induced by chemotherapeutic drugs.

    Science.gov (United States)

    Jia, Yue; Ohanyan, Aikoui; Lue, Yan-He; Swerdloff, Ronald S; Liu, Peter Y; Cohen, Pinchas; Wang, Christina

    2015-04-01

    Human (HN) prevents stress-induced apoptosis in many cells/tissues. In this study we showed that HN ameliorated chemotherapy [cyclophosphamide (CP) and Doxorubicin (DOX)]-induced male germ cell apoptosis both ex vivo in seminiferous tubule cultures and in vivo in the testis. HN acts by several putative mechanisms via binding to: an IL-12 like trimeric membrane receptor; BAX; or insulin-like growth factor binding protein-3 (IGFBP-3, a proapoptotic factor). To understand the mechanisms of HN on male germ cell apoptosis, we studied five HN analogues including: HNG (HN-S14G, a potent agonist), HNG-F6A (no binding to IGFBP-3), HN-S7A (no self-dimerization), HN-C8P (no binding to BAX), and HN-L12A (a HN antagonist) on CP-induced male germ cell apoptosis in mice. CP-induced germ cell apoptosis was inhibited by HN, HNG, HNG-F6A, HN-S7A, and HN-C8P (less effective); but not by HN-L12A. HN-L12A, but not HN-S7A or HN-C8P, blocked the protective effect of HN against CP-induced male germ cell apoptosis. HN, HN-S7A, and HN-C8P restored CP-suppressed STAT3 phosphorylation. These results suggest that HN: (1) decreases DOX (ex vivo) and CP (in vivo) induced male germ cell apoptosis; (2) action is mediated by the membrane receptor/STAT3 with minor contribution by BAX-binding pathway; (3) self-dimerization or binding to IGFBP-3 may not be involved in HN's effect in testis. HN is an important molecule in the regulation of germ cell homeostasis after injury and agonistic analogues may be developed for treating male infertility or protection against chemotherapy side effects.

  1. Chlorpheniramine Analogues Reverse Chloroquine Resistance in Plasmodium falciparum by Inhibiting PfCRT.

    Science.gov (United States)

    Deane, Karen J; Summers, Robert L; Lehane, Adele M; Martin, Rowena E; Barrow, Russell A

    2014-05-08

    The emergence and spread of malaria parasites that are resistant to chloroquine (CQ) has been a disaster for world health. The antihistamine chlorpheniramine (CP) partially resensitizes CQ-resistant (CQR) parasites to CQ but possesses little intrinsic antiplasmodial activity. Mutations in the parasite's CQ resistance transporter (PfCRT) confer resistance to CQ by enabling the protein to transport the drug away from its site of action, and it is thought that resistance-reversers such as CP exert their effect by blocking this CQ transport activity. Here, a series of new structural analogues and homologues of CP have been synthesized. We show that these compounds (along with other in vitro CQ resistance-reversers) inhibit the transport of CQ via a resistance-conferring form of PfCRT expressed in Xenopus laevis oocytes. Furthermore, the level of PfCRT-inhibition was found to correlate well with both the restoration of CQ accumulation and the level of CQ resensitization in CQR parasites.

  2. The role of inhibition by phosphocitrate and its analogue in chondrocyte differentiation and subchondral bone advance in Hartley guinea pigs.

    Science.gov (United States)

    Sun, Yubo; Kiraly, Alex J; Cox, Michael; Mauerhan, David R; Hanley, Edward N

    2018-04-01

    Phosphocitrate (PC) and its analogue, PC-β ethyl ester, inhibit articular cartilage degeneration in Hartley guinea pigs. However, the underlying molecular mechanisms remain unclear. The present study aimed to investigate the hypothesis that PC exerted its disease-modifying effect on osteoarthritis (OA), in part, by inhibiting a molecular program similar to that in the endochondral pathway of ossification. The results demonstrated that severe proteoglycan loss occurred in the superficial and middle zones, as well as in the calcified zone of articular cartilage in the Hartley guinea pigs. Subchondral bone advance was greater in the control Hartley guinea pigs compared with PC- or PC analogue-treated guinea pigs. Resorption of cartilage bars or islands and vascular invasion in the growth plate were also greater in the control guinea pigs compared with the PC- or PC analogue-treated guinea pigs. The levels of matrix metalloproteinase-13 and type X collagen within the articular cartilage and growth plate were significantly increased in the control guinea pigs compared with PC-treated guinea pigs (Pguinea pigs exhibited a hypertrophic phenotype and recapitulated a developmental molecular program similar to the endochondral pathway of ossification. Activation of this molecular program resulted in resorption of calcified articular cartilage and subchondral bone advance. This suggests that PC and PC analogues exerted their OA disease-modifying activity, in part, by inhibiting this molecular program.

  3. Compound A398, a novel podophyllotoxin analogue: cytotoxicity and induction of apoptosis in human leukemia cells.

    Directory of Open Access Journals (Sweden)

    Alethéia L Silveira

    Full Text Available Despite advances in oncology research, cancer is one of the leading causes of death worldwide. Thus, there is a demand for the development of more selective and effective antitumor agents. This study showed that A398, a novel podophyllotoxin analogue, was cytotoxic to the HT-29, MCF-7, MOLT-4 and HL-60 tumor cell lines, being less active in human peripheral blood mononuclear cells and normal cell lines FGH and IEC-6. Tests using the HepG2 lineage indicated that its metabolites do not contribute to its cytotoxicity. In the HL-60 cells, A398 induced apoptosis in a time and concentration-dependent manner, promoting mitochondrial depolarization, inhibition of Bcl-2, phosphatidylserine exposure, activation of caspases -8, -9 and -3, and DNA fragmentation. The production of reactive oxygen species does not seem to be a crucial event for the apoptotic process. Pretreatment with specific inhibitors of kinases ERK1/2, JNK and p38 resulted in an increased percentage of death induced by A398. These results indicate that the compound induced apoptosis through activation of intrinsic and extrinsic death pathways with the mechanism involving the inhibition of the MAPKs and Bcl-2. Taken together, our findings suggest that A398 has an anticancer potential, proving itself to be a candidate for preclinical studies.

  4. Streptococcal adhesin SspA/B analogue peptide inhibits adherence and impacts biofilm formation of Streptococcus mutans.

    Directory of Open Access Journals (Sweden)

    Tatsuro Ito

    Full Text Available Streptococcus mutans, the major causative agent of dental caries, adheres to tooth surfaces via the host salivary glycoprotein-340 (gp340. This adherence can be competitively inhibited by peptides derived from the SspA/B adhesins of Streptococcus gordonii, a human commensal microbe that competes for the same binding sites. Ssp(A4K-A11K, a double-lysine substituted SspA/B peptide analogue, has been shown to exhibit superior in vitro binding affinity for a gp340-derived peptide (SRCRP2, suggesting that Ssp(A4K-A11K may be of clinical interest. In the present work, we tested the inhibitory effects of Ssp(A4K-A11K on adherence and biofilm formation of S. mutans by reconstructing an artificial oral environment using saliva-coated polystyrene plates and hydroxyapatite disks. Bacterial adherence (adherence period: 1 h was assessed by an enzyme-linked immunosorbent assay using biotinylated bacterial cells. Biofilm formation (periods: 8, 11, or 14 h was assessed by staining and imaging of the sessile cells, or by recovering biofilm cells and plating for cell counts. The pH values of the culture media were measured as a biofilm acidogenicity indicator. Bactericidality was measured by loss of optical density during culturing in the presence of the peptide. We observed that 650 μM Ssp(A4K-A11K significantly inhibited adherence of S. mutans to saliva-coated polystyrene; a similar effect was seen on bacterial affinity for SRCRP2. Ssp(A4K-A11K had lesser effects on the adherence of commensal streptococci. Pretreatment of polystyrene and hydroxyapatite with 650 μM Ssp(A4K-A11K significantly attenuated biofilm formation, whether tested with glucose- or sucrose-containing media. The SspA/B peptide's activity did not reflect bactericidality. Strikingly, pH in Ssp-treated 8-h (6.8 ± 0.06 and 11-h (5.5 ± 0.06 biofilms showed higher values than the critical pH. Thus, Ssp(A4K-A11K acts by inhibiting bacterial adherence and cariogrnic biofilm formation. We further

  5. Modulation of IL-33/ST2-TIR and TLR signalling pathway by fingolimod and analogues in immune cells.

    Science.gov (United States)

    Rüger, K; Ottenlinger, F; Schröder, M; Zivković, A; Stark, H; Pfeilschifter, J M; Radeke, H H

    2014-12-01

    For the immune modulatory drug fingolimod (FTY720), lymphocyte sequestration has been extensively studied and accepted as mode of action. Further, direct effects on immune cell signalling are incompletely understood. Herein, we used the parent drug and newly synthesized analogues to investigate their effects on dendritic cell (DC) calcium signalling and on Th1, Th2 and Th17 responses. DC calcium signalling was determined with a single cell-based confocal assay and IL-33/ST2-TIR Th2-like response with ST2-transduced EL4-6.1 thymoma cells. The Th1/Th17 responses were examined with a LPS/TLR-enhanced antigen presentation assay with OVA-TCRtg CD4 and CD8 spleen cells. Our results revealed a comparable influence of fingolimod and S1P on intracellular calcium level in DC, while an oxy-derivative of fingolimod exhibited an EC50 of 3.3 nm, being 14 times more potent than FTY720-P. The IL-33/ST2-TIR Th2-like response in ST2-EL4 cells was inhibited by fingolimod and analogues at varying degrees. Using the OVA-TCRtg LPS/TLR-enhanced spleen cell assay, we found that fingolimod inhibited both IL-17 and IFN-γ production. In contrast, fingolimod phosphate failed to decrease Th1 cytokines. Interestingly, the effects of the parent compound fingolimod were modulated by the PP2A inhibitor okadaic acid, thus suggesting PP2A as relevant intracellular target. These studies describe detailed immune-modulating properties of fingolimod, including interference with a prototypical Th2 response via IL-33/ST2-TIR. Moreover, differential effects of fingolimod versus its phosphorylated derivative on TLR-activated and antigen-dependent Th1 activation suggest PP2A as an additional target of fingolimod immune therapy. Together with the analogues tested, these data may guide the development of more specific fingolimod derivatives. © 2014 John Wiley & Sons Ltd.

  6. Cytotoxicity Study of Cyclopentapeptide Analogues of Marine Natural Product Galaxamide towards Human Breast Cancer Cells

    Directory of Open Access Journals (Sweden)

    Jignesh Lunagariya

    2017-01-01

    Full Text Available Herein, we report the cytotoxicity of cyclopentapeptide analogues of marine natural product galaxamide towards breast carcinoma cells and the underlying mechanisms. We examined the effect of the novel galaxamide analogues on cancer cell proliferation by MTT assay and also further examined the most active compound for morphological changes using Hoechst33342 staining technique, induction of apoptosis, cell cycle phases, mitochondrial membrane potential (MMP, and reactive oxygen species (ROS generation using flow cytometry in human breast cancer MCF-7 cells in vitro. Galaxamide and its analogues effectively induced toxicity in human hepatocellular carcinoma HepG2, human breast carcinoma MCF-7, human epitheloid cervix carcinoma HeLa, and human breast carcinoma MB-MDA-231 cell lines. Amongst them, compound 3 exhibited excellent toxicity towards MCF-7 cells. This galaxamide analogue significantly induced apoptosis in a dose-dependent manner in MCF-7 cells involves cell cycle arrest in the G1 phase, a reduction of MMP, and a marked increase in generation of ROS. Particularly, compound 3 of galaxamide analogues might be a potential candidate for the treatment of breast cancer.

  7. Vanillin Analogues o-Vanillin and 2,4,6-Trihydroxybenzaldehyde Inhibit NFĸB Activation and Suppress Growth of A375 Human Melanoma.

    Science.gov (United States)

    Marton, Annamária; Kúsz, Erzsébet; Kolozsi, Csongor; Tubak, Vilmos; Zagotto, Giuseppe; Buzás, Krisztina; Quintieri, Luigi; Vizler, Csaba

    2016-11-01

    Constitutive activation of nuclear factor kappa-B (NFĸB) is a hallmark of various cancer types, including melanoma. Chemotherapy may further increase tumour NFĸB activity, a phenomenon that, in turn, exacerbates drug resistance. This study aimed at preliminary screening of a panel of aromatic aldehydes, including vanillin, for cytotoxicity and suppression of tumour cell NFĸB activity. The cytotoxic and NFĸB-inhibitory effects of 10 aromatic aldehydes, including vanillin, were investigated in cultured A375 human melanoma cells. Each compound was assayed alone and in combination with the model NFĸB-activating drug doxorubicin. The most promising analogues were then tested alone and in combination with 4-hydroperoxycyclophosphamide in vitro, and with cyclophosphamide in mice bearing A375 xenografts. The vanillin analogues o-vanillin and 2,4,6-trihydroxybenzaldehyde exhibited cytotoxicity against cultured A375 cells, and inhibited doxorubicin- and 4-hydroperoxycyclophosphamide-induced NFĸB activation. They also suppressed A375 cell growth in mice. o-vanillin and 2,4,6-trihydroxybenzaldehyde deserve further evaluation as potential anticancer drugs. Copyright© 2016 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

  8. Anandamide inhibits adhesion and migration of breast cancer cells

    International Nuclear Information System (INIS)

    Grimaldi, Claudia; Pisanti, Simona; Laezza, Chiara; Malfitano, Anna Maria; Santoro, Antonietta; Vitale, Mario; Caruso, Maria Gabriella; Notarnicola, Maria; Iacuzzo, Irma; Portella, Giuseppe; Di Marzo, Vincenzo; Bifulco, Maurizio

    2006-01-01

    The endocannabinoid system regulates cell proliferation in human breast cancer cells. We reasoned that stimulation of cannabinoid CB 1 receptors could induce a non-invasive phenotype in breast mtastatic cells. In a model of metastatic spreading in vivo, the metabolically stable anandamide analogue, 2-methyl-2'-F-anandamide (Met-F-AEA), significantly reduced the number and dimension of metastatic nodes, this effect being antagonized by the selective CB 1 antagonist SR141716A. In MDA-MB-231 cells, a highly invasive human breast cancer cell line, and in TSA-E1 cells, a murine breast cancer cell line, Met-F-AEA inhibited adhesion and migration on type IV collagen in vitro without modifying integrin expression: both these effects were antagonized by SR141716A. In order to understand the molecular mechanism involved in these processes, we analyzed the phosphorylation of FAK and Src, two tyrosine kinases involved in migration and adhesion. In Met-F-AEA-treated cells, we observed a decreased tyrosine phosphorylation of both FAK and Src, this effect being attenuated by SR141716A. We propose that CB 1 receptor agonists inhibit tumor cell invasion and metastasis by modulating FAK phosphorylation, and that CB 1 receptor activation might represent a novel therapeutic strategy to slow down the growth of breast carcinoma and to inhibit its metastatic diffusion in vivo

  9. Epigenetics Reactivation of Nrf2 in Prostate TRAMP C1 Cells by Curcumin Analogue FN1.

    Science.gov (United States)

    Li, Wenji; Pung, Doug; Su, Zheng-Yuan; Guo, Yue; Zhang, Chengyue; Yang, Anne Yuqing; Zheng, Xi; Du, Zhi-Yun; Zhang, Kun; Kong, Ah-Ng

    2016-04-18

    It has previously been shown that curcumin can effectively inhibit prostate cancer proliferation and progression in TRAMP mice, potentially acting through the hypomethylation of the Nrf2 gene promoter and hence activation of the Nrf2 pathway to enhance cell antioxidative defense. FN1 is a synthetic curcumin analogue that shows stronger anticancer activity than curcumin in other reports. We aimed to explore the epigenetic modification of FN1 that restores Nrf2 expression in TRAMP-C1 cells. Stably transfected HepG2-C8 cells were used to investigate the effect of FN1 on the Nrf2- antioxidant response element (ARE) pathway. Real-time quantitative PCR and Western blotting were applied to study the influence of FN1 on endogenous Nrf2 and its downstream genes. Bisulfite genomic sequencing (BGS) and methylated DNA immunoprecipitation (MeDIP) were then performed to examine the methylation profile of the Nrf2 promoter. An anchorage-independent colony-formation analysis was conducted to examine the tumor inhibition activity of FN1. Epigenetic modification enzymes, including DNMTs and HDACs, were investigated by Western blotting. The luciferase reporter assay indicated that FN1 was more potent than curcumin in activating the Nrf2-ARE pathway. FN1 increased the expression of Nrf2 and its downstream detoxifying enzymes. FN1 significantly inhibited the colony formation of TRAMP-C1 cells. BGS and MeDIP assays revealed that FN1 treatment (250 nM for 3 days) reduced the percentage of CpG methylation of the Nrf2 promoter. FN1 also downregulated epigenetic modification enzymes. In conclusion, our results suggest that FN1 is a novel anticancer agent for prostate cancer. In the TRAMP-C1 cell line, FN1 can increase the level of Nrf2 and downstream genes via activating the Nrf2-ARE pathway and inhibit the colony formation potentially through the decreased expression of keap1 coupled with CpG demethylation of the Nrf2 promoter. This CpG demethylation effect may come from decreased

  10. Reaction Characteristics of Andrographolide and its Analogue AL-1 with GSH, as a Simple Chemical Simulation of NF-κB Inhibition

    Directory of Open Access Journals (Sweden)

    Yuqiang Wang

    2012-01-01

    Full Text Available 14-α-Lipoic acid-3,19-dihydroxyandrographolide (AL-1, 2 is an analogue of andrographolide (Andro, 1 coupled to α-lipoic acid (LA, 4. AL-1 was at least 10-fold more potent than the natural parent compound Andro in inhibiting nuclear factor (NF-κB activation in RIN-m cells. In the present study, glutathione (GSH, 3 was used as a simple chemical model molecule of NF-κB with cysteine 62. The characteristics of the reaction between AL-1 or Andro and GSH were investigated to trace some possible elucidation for the inhibitive mechanism and stronger inhibition of AL-1 to NF-κB activation. The results showed that the main reaction products of AL-1 and Andro were identical, sulfhydryl adduct and amino adduct. AL-1 reacted much faster than Andro with GSH. The product yield of AL-1 was much higher than that of Andro. It was speculated that AL-1 might inhibit NF-κB by the same mechanism as Andro. And the faster reaction rate and higher yield may account for the stronger NF-κB inhibition of AL-1 when compared with Andro.

  11. Epoxyeicosatrienoic acid analogue lowers blood pressure through vasodilation and sodium channel inhibition

    Czech Academy of Sciences Publication Activity Database

    Khan, M. A. H.; Pavlov, T. S.; Christain, S. V.; Neckář, Jan; Staruschenko, A.; Gauthier, K. M.; Capdevila, J. H.; Falck, J. R.; Campbell, W. B.; Imig, J. D.

    2014-01-01

    Roč. 127, č. 7 (2014), s. 463-474 ISSN 0143-5221 Institutional support: RVO:67985823 Keywords : angiotensin II * epithelial sodium channel (ENaC) * epoxyeicosatrienoic acid analogue * hypertension Subject RIV: FA - Cardiovascular Diseases incl. Cardiotharic Surgery Impact factor: 5.598, year: 2014

  12. Dimethoxycurcumin, a metabolically stable analogue of curcumin enhances the radiosensitivity of cancer cells: Possible involvement of ROS and thioredoxin reductase

    Energy Technology Data Exchange (ETDEWEB)

    Jayakumar, Sundarraj; Patwardhan, R.S.; Pal, Debojyoti [Radiation Biology & Health Sciences Division, Modular Laboratories, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India); Sharma, Deepak [Radiation Biology & Health Sciences Division, Modular Laboratories, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India); Homi Bhabha National Institute, Anushaktinagar, Mumbai 400094 (India); Sandur, Santosh K., E-mail: sskumar@barc.gov.in [Radiation Biology & Health Sciences Division, Modular Laboratories, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India); Homi Bhabha National Institute, Anushaktinagar, Mumbai 400094 (India)

    2016-09-09

    Dimethoxycurcumin (DIMC), a structural analogue of curcumin, has been shown to have more stability, bioavailability, and effectiveness than its parent molecule curcumin. In this paper the radiosensitizing effect of DIMC has been investigated in A549 lung cancer cells. As compared to its parent molecule curcumin, DIMC showed a very potent radiosensitizing effect as seen by clonogenic survival assay. DIMC in combination with radiation significantly increased the apoptosis and mitotic death in A549 cells. This combinatorial treatment also lead to effective elimination of cancer stem cells. Further, there was a significant increase in cellular ROS, decrease in GSH to GSSG ratio and also significant slowdown in DNA repair when DIMC was combined with radiation. In silico docking studies and in vitro studies showed inhibition of thioredoxin reductase enzyme by DIMC. Overexpression of thioredoxin lead to the abrogation of radiosensitizing effect of DIMC underscoring the role of thioredoxin reductase in radiosensitization. Our results clearly demonstrate that DIMC can synergistically enhance the cancer cell killing when combined with radiation by targeting thioredoxin system. - Highlights: • DIMC enhances radiosensitivity of cancer cells by inducing cell death. • DIMC with radiation disrupted the cellular redox and targeted cancer stem cells. • DNA repair is hampered when cells are treated with DIMC. • DIMC inhibited thioredoxin reductase in cancer cells.

  13. Dimethoxycurcumin, a metabolically stable analogue of curcumin enhances the radiosensitivity of cancer cells: Possible involvement of ROS and thioredoxin reductase

    International Nuclear Information System (INIS)

    Jayakumar, Sundarraj; Patwardhan, R.S.; Pal, Debojyoti; Sharma, Deepak; Sandur, Santosh K.

    2016-01-01

    Dimethoxycurcumin (DIMC), a structural analogue of curcumin, has been shown to have more stability, bioavailability, and effectiveness than its parent molecule curcumin. In this paper the radiosensitizing effect of DIMC has been investigated in A549 lung cancer cells. As compared to its parent molecule curcumin, DIMC showed a very potent radiosensitizing effect as seen by clonogenic survival assay. DIMC in combination with radiation significantly increased the apoptosis and mitotic death in A549 cells. This combinatorial treatment also lead to effective elimination of cancer stem cells. Further, there was a significant increase in cellular ROS, decrease in GSH to GSSG ratio and also significant slowdown in DNA repair when DIMC was combined with radiation. In silico docking studies and in vitro studies showed inhibition of thioredoxin reductase enzyme by DIMC. Overexpression of thioredoxin lead to the abrogation of radiosensitizing effect of DIMC underscoring the role of thioredoxin reductase in radiosensitization. Our results clearly demonstrate that DIMC can synergistically enhance the cancer cell killing when combined with radiation by targeting thioredoxin system. - Highlights: • DIMC enhances radiosensitivity of cancer cells by inducing cell death. • DIMC with radiation disrupted the cellular redox and targeted cancer stem cells. • DNA repair is hampered when cells are treated with DIMC. • DIMC inhibited thioredoxin reductase in cancer cells.

  14. Chalcones from Chinese liquorice inhibit proliferation of T cells and production of cytokines

    DEFF Research Database (Denmark)

    Barfod, Lea; Kemp, Kåre; Hansen, Majbritt

    2002-01-01

    Licochalcone A (LicA), an oxygenated chalcone, has been shown to inhibit the growth of both parasites and bacteria. In this study, we investigated the effect of LicA and four synthetic analogues on the activity of human peripheral blood mononuclear cell proliferation and cytokine production. Four...... out of five chalcones tested inhibited the proliferation of lymphocytes measured by thymidine incorporation and by flow cytometry. The production of pro- and anti-inflammatory cytokines from monocytes and T cells was also inhibited by four of five chalcones. Furthermore, intracellular detection...... of cytokines revealed that the chalcones inhibited the production rather than the release of the cytokines. Taken together, these results indicate that LicA and some analogues may have immunomodulatory effects, and may thus be candidates not only as anti-microbial agents, but also for the treatment of other...

  15. 7-Piperazinethylchrysin inhibits melanoma cell proliferation by ...

    African Journals Online (AJOL)

    In B16F10 and A375 cells, treatment with PEC caused the inhibition ... Conclusion: PEC inhibited melanoma cell proliferation, apparently by blocking the cell cycle at G0/G1 .... all statistical analyses. .... Financial support from the Department of.

  16. Piracetam and TRH analogues antagonise inhibition by barbiturates, diazepam, melatonin and galanin of human erythrocyte D-glucose transport

    Science.gov (United States)

    Naftalin, Richard J; Cunningham, Philip; Afzal-Ahmed, Iram

    2004-01-01

    Nootropic drugs increase glucose uptake into anaesthetised brain and into Alzheimer's diseased brain. Thyrotropin-releasing hormone, TRH, which has a chemical structure similar to nootropics increases cerebellar uptake of glucose in murine rolling ataxia. This paper shows that nootropic drugs like piracetam (2-oxo 1 pyrrolidine acetamide) and levetiracetam and neuropeptides like TRH antagonise the inhibition of glucose transport by barbiturates, diazepam, melatonin and endogenous neuropeptide galanin in human erythrocytes in vitro. The potencies of nootropic drugs in opposing scopolamine-induced memory loss correlate with their potencies in antagonising pentobarbital inhibition of erythrocyte glucose transport in vitro (Pnootropics, D-levetiracetam and D-pyroglutamate, have higher antagonist Ki's against pentobarbital inhibition of glucose transport than more potent L-stereoisomers (Pnootropics, like aniracetam and levetiracetam, while antagonising pentobarbital action, also inhibit glucose transport. Analeptics like bemigride and methamphetamine are more potent inhibitors of glucose transport than antagonists of hypnotic action on glucose transport. There are similarities between amino-acid sequences in human glucose transport protein isoform 1 (GLUT1) and the benzodiazepine-binding domains of GABAA (gamma amino butyric acid) receptor subunits. Mapped on a 3D template of GLUT1, these homologies suggest that the site of diazepam and piracetam interaction is a pocket outside the central hydrophilic pore region. Nootropic pyrrolidone antagonism of hypnotic drug inhibition of glucose transport in vitro may be an analogue of TRH antagonism of galanin-induced narcosis. PMID:15148255

  17. Aberrant Apoptotic Response of Colorectal Cancer Cells to Novel Nucleoside Analogues.

    Directory of Open Access Journals (Sweden)

    Leonie Harmse

    Full Text Available Despite the increased understanding of colorectal cancer and the introduction of targeted drug therapy, the metastatic phase of the disease remains refractory to treatment. Since the deregulation of normal apoptosis contributes to the pathogenesis of colorectal cancer, novel nucleoside analogues were synthesized here and evaluated for their ability to induce apoptosis and cause cell death in two colorectal adeno-carcinoma cell lines, Caco-2 and HT-29. Three novel nucleoside analogues assessed here showed cytotoxic activity, as measured by the MTT assay against both cell lines: the IC50 values ranged between 3 and 37 μM, with Caco-2 cells being more sensitive than HT-29 cells. Compared to camptothecin, the positive control, the nucleoside analogues were significantly less toxic to normal unstimulated leukocytes (p>0.05. Moreover, the nucleosides were able to induce apoptosis as measured by an increase in caspase 8 and caspase 3 activity above that of the control. This was additionally supported by data derived from Annexin V-FITC assays. Despite marginal changes to the mitochondrial membrane potential, all three nucleosides caused a significant increase in cytosolic cytochrome c (p>0.05, with a corresponding decrease in mitochondrial cytochrome c. Morphological analysis of both cell lines showed the rapid appearance of vacuoles following exposure to two of the nucleosides, while a third caused cellular detachment, delayed cytoplasmic vacuolisation and nuclear abnormalities. Preliminary investigations, using the autophagic indicator monodansylcadaverine and chloroquine as positive control, showed that two of the nucleosides induced the formation of autophagic vacuoles. In summary, the novel nucleoside analogues showed selective cytotoxicity towards both cancer cell lines and are effective initiators of an unusual apoptotic response, demonstrating their potential to serve as structural scaffolds for more potent analogues.

  18. Aberrant Apoptotic Response of Colorectal Cancer Cells to Novel Nucleoside Analogues.

    Science.gov (United States)

    Harmse, Leonie; Dahan-Farkas, Nurit; Panayides, Jenny-Lee; van Otterlo, Willem; Penny, Clement

    2015-01-01

    Despite the increased understanding of colorectal cancer and the introduction of targeted drug therapy, the metastatic phase of the disease remains refractory to treatment. Since the deregulation of normal apoptosis contributes to the pathogenesis of colorectal cancer, novel nucleoside analogues were synthesized here and evaluated for their ability to induce apoptosis and cause cell death in two colorectal adeno-carcinoma cell lines, Caco-2 and HT-29. Three novel nucleoside analogues assessed here showed cytotoxic activity, as measured by the MTT assay against both cell lines: the IC50 values ranged between 3 and 37 μM, with Caco-2 cells being more sensitive than HT-29 cells. Compared to camptothecin, the positive control, the nucleoside analogues were significantly less toxic to normal unstimulated leukocytes (p>0.05). Moreover, the nucleosides were able to induce apoptosis as measured by an increase in caspase 8 and caspase 3 activity above that of the control. This was additionally supported by data derived from Annexin V-FITC assays. Despite marginal changes to the mitochondrial membrane potential, all three nucleosides caused a significant increase in cytosolic cytochrome c (p>0.05), with a corresponding decrease in mitochondrial cytochrome c. Morphological analysis of both cell lines showed the rapid appearance of vacuoles following exposure to two of the nucleosides, while a third caused cellular detachment, delayed cytoplasmic vacuolisation and nuclear abnormalities. Preliminary investigations, using the autophagic indicator monodansylcadaverine and chloroquine as positive control, showed that two of the nucleosides induced the formation of autophagic vacuoles. In summary, the novel nucleoside analogues showed selective cytotoxicity towards both cancer cell lines and are effective initiators of an unusual apoptotic response, demonstrating their potential to serve as structural scaffolds for more potent analogues.

  19. Protein expression changes induced in a malignant melanoma cell line by the curcumin analogue compound D6

    International Nuclear Information System (INIS)

    Pisano, Marina; Palomba, Antonio; Tanca, Alessandro; Pagnozzi, Daniela; Uzzau, Sergio; Addis, Maria Filippa; Dettori, Maria Antonietta; Fabbri, Davide; Palmieri, Giuseppe; Rozzo, Carla

    2016-01-01

    We have previously demonstrated that the hydroxylated biphenyl compound D6 (3E,3′E)-4,4′-(5,5′,6,6′-tetramethoxy-[1,1′-biphenyl]-3,3′-diyl)bis (but-3-en-2-one), a structural analogue of curcumin, exerts a strong antitumor activity on melanoma cells both in vitro and in vivo. Although the mechanism of action of D6 is yet to be clarified, this compound is thought to inhibit cancer cell growth by arresting the cell cycle in G2/M phase, and to induce apoptosis through the mitochondrial intrinsic pathway. To investigate the changes in protein expression induced by exposure of melanoma cells to D6, a differential proteomic study was carried out on D6-treated and untreated primary melanoma LB24Dagi cells. Proteins were fractionated by SDS-PAGE and subjected to in gel digestion. The peptide mixtures were analyzed by liquid chromatography coupled with tandem mass spectrometry. Proteins were identified and quantified using database search and spectral counting. Proteomic data were finally uploaded into the Ingenuity Pathway Analysis software to find significantly modulated networks and pathways. Analysis of the differentially expressed protein profiles revealed the activation of a strong cellular stress response, with overexpression of several HSPs and stimulation of ubiquitin-proteasome pathways. These were accompanied by a decrease of protein synthesis, evidenced by downregulation of proteins involved in mRNA processing and translation. These findings are consistent with our previous results on gene expression profiling in melanoma cells treated with D6. Our findings confirm that the curcumin analogue D6 triggers a strong stress response in melanoma cells, turning down majority of cell functions and finally driving cells to apoptosis. The online version of this article (doi:10.1186/s12885-016-2362-6) contains supplementary material, which is available to authorized users

  20. New antagonists of LHRH. II. Inhibition and potentiation of LHRH by closely related analogues.

    Science.gov (United States)

    Bajusz, S; Csernus, V J; Janaky, T; Bokser, L; Fekete, M; Schally, A V

    1988-12-01

    Modifications of the previously described LHRH antagonists, [Ac-D-Nal(2)1, D-Phe(4Cl)2, D-Trp3, D-Cit6, D-Ala10]LHRH and the corresponding D-Hci6 analogue, have been made to alter the hydrophobicity of the N-terminal acetyl-tripeptide portion. Substitution of D-Trp3 with the less hydrophobic D-Pal(3) had only marginal effects on the antagonistic activities and receptor binding potencies of the D-Cit/D-Hci6 analogues, but it appeared to further improve the toxicity lowering effect of D-Cit/D-Hci6 substitution. Antagonists containing D-Pal(3)3 and D-Cit/D-Hci6 residues, i.e. [Ac-D-Nal(2)1, D-Phe(4Cl)2, D-Pal(3)3, D-Cit6, D-Ala10]LHRH (SB-75) and [Ac-D-Nal(2)1, D-Phe(4Cl)2, D-Pal(3)3, D-Hci6, D-Ala10]LHRH (SB-88), were completely free of the toxic effects, such as cyanosis and respiratory depression leading to death, which have been observed in rats with the D-Trp3, D-Arg6 antagonist and related antagonists. Replacement of the N-acetyl group with the hydrophilic carbamoyl group caused a slight decrease in antagonistic activities, particularly in vitro. Introduction of urethane type acyl group such as methoxycarbonyl (Moc) or t-butoxycarbonyl (Boc) led to analogues that showed LHRH-potentiating effect. The increase in potency induced by these analogues, e.g. [Moc-D-Nal(2)1, D-Phe(4Cl)2, D-Trp3, D-Cit6, D-Ala10]LHRH and [Boc-D-Phe1, D-Phe(4Cl)2, D-Pal(3)3, D-Cit6, D-Ala10]LHRH, was 170-260% and persisted for more than 2 h when studied in a superfused rat pituitary system.

  1. Quantitative structure-activity analysis of acetylcholinesterase inhibition by oxono and thiono analogues of organophosphorus compounds. (Reannouncement with new availability information)

    Energy Technology Data Exchange (ETDEWEB)

    Maxwell, D.M.; Brecht, K.M.

    1992-02-01

    A comparison of the bimolecular rate constants (ki) for inhibition of electric eel acetylcholinesterase (AChE) by the oxono (i.e., P=O) and thiono (i.e., P=S) analogues of parathion, methylparathion, leptophos, fonofos, sarin, and soman revealed that the oxono/thiono ratios of ki values varied from 14 for soman to 1240 for parathion. Analysis of the relative importance of the dissociation equilibrium constant and the phosphorylation rate constant in producing this variation in ki values indicated that the oxono analogues had phosphorylation rate constant values that varied in a narrow range from 8- to 14-fold greater than their thiono counterparts, while the oxono/thiono ratios for dissociation constants varied widely from 1 for soman to 82 for fonofos. The lower affinities of thiono analogues for AChE probably resulted from differences in the hydrophobic binding of oxono and thiono analogues to the active site of AChE, inasmuch as the hydrophobicities (i.e., octanol/water partition coefficients) of thiono organophosphorus compounds were much greater than the hydrophobicities of their oxono analogues. Quantitative structure-activity analysis indicated that the hydrophobic effects of oxono and thiono moieties correlated with log ki for AChE inhibition to a greater extent (r2 = 0.79) than their electronic effects (r2 equal to or less than 0.48). These observations suggest that the differences in hydrophobicity of oxono and thiono analogues of organophosphorus compounds may be as important as their electronic differences in determining their effectiveness as AChE inhibitors. Acetylcholinesterase, soman (GD), structure-activity analysis inhibition, oxono analogues, thiono analogues.

  2. Mechanism of MenE inhibition by acyl-adenylate analogues and discovery of novel antibacterial agents.

    Science.gov (United States)

    Matarlo, Joe S; Evans, Christopher E; Sharma, Indrajeet; Lavaud, Lubens J; Ngo, Stephen C; Shek, Roger; Rajashankar, Kanagalaghatta R; French, Jarrod B; Tan, Derek S; Tonge, Peter J

    2015-10-27

    MenE is an o-succinylbenzoyl-CoA (OSB-CoA) synthetase in the bacterial menaquinone biosynthesis pathway and is a promising target for the development of novel antibacterial agents. The enzyme catalyzes CoA ligation via an acyl-adenylate intermediate, and we have previously reported tight-binding inhibitors of MenE based on stable acyl-sulfonyladenosine analogues of this intermediate, including OSB-AMS (1), which has an IC50 value of ≤25 nM for Escherichia coli MenE. Herein, we show that OSB-AMS reduces menaquinone levels in Staphylococcus aureus, consistent with its proposed mechanism of action, despite the observation that the antibacterial activity of OSB-AMS is ∼1000-fold lower than the IC50 for enzyme inhibition. To inform the synthesis of MenE inhibitors with improved antibacterial activity, we have undertaken a structure-activity relationship (SAR) study stimulated by the knowledge that OSB-AMS can adopt two isomeric forms in which the OSB side chain exists either as an open-chain keto acid or a cyclic lactol. These studies revealed that negatively charged analogues of the keto acid form bind, while neutral analogues do not, consistent with the hypothesis that the negatively charged keto acid form of OSB-AMS is the active isomer. X-ray crystallography and site-directed mutagenesis confirm the importance of a conserved arginine for binding the OSB carboxylate. Although most lactol isomers tested were inactive, a novel difluoroindanediol inhibitor (11) with improved antibacterial activity was discovered, providing a pathway toward the development of optimized MenE inhibitors in the future.

  3. Meta-iodobenzylguanidine inhibits complex I and III of the respiratory chain in the human cell line Molt-4

    NARCIS (Netherlands)

    Cornelissen, J.; Wanders, R. J.; van Gennip, A. H.; van den Bogert, C.; Voûte, P. A.; van Kuilenburg, A. B.

    1995-01-01

    In this paper we report the effects of meta-iodobenzylguanidine (MIBG), a structural analogue of norepinephrine, on cell proliferation and several parameters related to mitochondrial respiration in Molt-4 cells. In micromolar concentrations, MIBG completely inhibited the proliferation of Molt-4

  4. Kaempferol inhibits cell proliferation and glycolysis in esophagus squamous cell carcinoma via targeting EGFR signaling pathway.

    Science.gov (United States)

    Yao, Shihua; Wang, Xiaowei; Li, Chunguang; Zhao, Tiejun; Jin, Hai; Fang, Wentao

    2016-08-01

    Antitumor activity of kaempferol has been studied in various tumor types, but its potency in esophagus squamous cell carcinoma is rarely known. Here, we reported the activity of kaempferol against esophagus squamous cell carcinoma as well as its antitumor mechanisms. Results of cell proliferation and colony formation assay showed that kaempferol substantially inhibited tumor cell proliferation and clone formation in vitro. Flow cytometric analysis demonstrated that tumor cells were induced G0/G1 phase arrest after kaempferol treatment, and the expression of protein involved in cell cycle regulation was dramatically changed. Except the potency on cell proliferation, we also discovered that kaempferol had a significant inhibitory effect against tumor glycolysis. With the downregulation of hexokinase-2, glucose uptake and lactate production in tumor cells were dramatically declined. Mechanism studies revealed kaempferol had a direct effect on epidermal growth factor receptor (EGFR) activity, and along with the inhibition of EGFR, its downstream signaling pathways were also markedly suppressed. Further investigations found that exogenous overexpression of EGFR in tumor cells substantially attenuated glycolysis suppression induced by kaempferol, which implied that EGFR also played an important role in kaempferol-mediated glycolysis inhibition. Finally, the antitumor activity of kaempferol was validated in xenograft model and kaempferol prominently restrained tumor growth in vivo. Meanwhile, dramatic decrease of EGFR activity and hexokinase-2 expression were observed in kaempferol-treated tumor tissue, which confirmed these findings in vitro. Briefly, these studies suggested that kaempferol, or its analogues, may serve as effective candidates for esophagus squamous cell carcinoma management.

  5. Novel Indole-based Tambjamine-Analogues Induce Apoptotic Lung Cancer Cell Death through p38 Mitogen-Activated Protein Kinase Activation.

    Science.gov (United States)

    Manuel-Manresa, Pilar; Korrodi-Gregório, Luís; Hernando, Elsa; Villanueva, Alberto; Martínez-García, David; Rodilla, Ananda M; Ramos, Ricard; Fardilha, Margarida; Moya, Juan; Quesada, Roberto; Soto-Cerrato, Vanessa; Pérez-Tomás, Ricardo

    2017-07-01

    Lung cancer has become the leading killer cancer worldwide, due to late diagnosis and lack of efficient anticancer drugs. We have recently described novel natural-derived tambjamine analogues that are potent anion transporters capable of disrupting cellular ion balance, inducing acidification of the cytosol and hyperpolarization of cellular plasma membranes. Although these tambjamine analogues were able to compromise cell survival, their molecular mechanism of action remains largely unknown. Herein we characterize the molecular cell responses induced by highly active indole-based tambjamine analogues treatment in lung cancer cells. Expression changes produced after compounds treatment comprised genes related to apoptosis, cell cycle, growth factors and its receptors, protein kinases and topoisomerases, among others. Dysregulation of BCL2 and BIRC5 /survivin genes suggested the apoptotic pathway as the induced molecular cell death mechanism. In fact, activation of several proapoptotic markers (caspase-9, caspase-3, and PARP) and reversion of the cytotoxic effect upon treatment with an apoptosis inhibitor (Z-VAD-FMK) were observed. Moreover, members of the Bcl-2 protein family suffered changes after tambjamine analogues treatment, with a concomitant protein decrease towards the prosurvival members. Besides this, it was observed cellular accumulation of ROS upon compound treatment and an activation of the stress-kinase p38 MAPK route that, when inhibited, reverted the cytotoxic effect of the tambjamine analogues. Finally, a significant therapeutic effect of these compounds was observed in subcutaneous and orthotopic lung cancer mice models. Taken together, these results shed light on the mechanism of action of novel cytotoxic anionophores and demonstrate the therapeutic effects against lung cancer. Mol Cancer Ther; 16(7); 1224-35. ©2017 AACR . ©2017 American Association for Cancer Research.

  6. In vitro effects of substance P analogue [D-Arg1, D-Phe5, D-Trp7,9, Leu11] substance P on human tumour and normal cell growth.

    OpenAIRE

    Everard, M. J.; Macaulay, V. M.; Miller, J. L.; Smith, I. E.

    1992-01-01

    Analogues of the neurotransmitter substance P (SP) can interact with neuropeptide receptors, and are reported to inhibit growth of small cell lung cancer cell lines (SCLC CLs). We found [D-Arg1, D-Phe5, D-Trp7,9, Leu11] substance P (D-Phe5SP) significantly inhibited DNA synthesis by 10/10 human tumour CLs; six SCLC, one N-SCLC (squamous), two ovarian and one squamous cervical carcinoma, with inhibition to 50% control levels (IC50) of 20-50 microM. There was dose dependent inhibition of colony...

  7. Cytostatic versus Cytocidal Activities of Chloroquine Analogues and Inhibition of Hemozoin Crystal Growth

    OpenAIRE

    Gorka, Alexander P.; Alumasa, John N.; Sherlach, Katy S.; Jacobs, Lauren M.; Nickley, Katherine B.; Brower, Jonathan P.; de Dios, Angel C.; Roepe, Paul D.

    2013-01-01

    We report an improved, nonhazardous, high-throughput assay for in vitro quantification of antimalarial drug inhibition of β-hematin (hemozoin) crystallization performed under conditions that are more physiological relative to previous assays. The assay uses the differential detergent solubility of crystalline and noncrystalline forms of heme and is optimized via the use of lipid catalyst. Using this assay, we quantify the effect of pH on the crystal growth-inhibitory activities of current qui...

  8. Do GnRH analogues directly affect human endometrial epithelial cell gene expression?

    KAUST Repository

    Zhang, Xiaomei

    2010-03-04

    We examined whether Gonadotrophin-releasing hormone (GnRH) analogues [leuprolide acetate (LA) and ganirelix acetate (GA)] modulate gene expression in Ishikawa cells used as surrogate for human endometrial epithelial cells in vitro. The specific aims were: (i) to study the modulatory effect of GnRH analogues by RT-PCR [in the absence and presence of E2 and P4, and cyclic adenosine monophos-phate (cAMP)] on mRNA expression of genes modulated during the window of implantation in GnRH analogues/rFSH-treated assisted reproductive technology cycles including OPTINEURIN (OPTN), CHROMATIN MODIFYING PROTEIN (CHMP1A), PROSAPOSIN (PSAP), IGFBP-5 and SORTING NEXIN 7 (SNX7), and (ii) to analyze the 5\\'-flanking regions of such genes for the presence of putative steroid-response elements [estrogen-response elements (EREs) and P4-response element (PREs)]. Ishikawa cells were cytokeratin+/vimentin2 and expressed ERa,ERb, PR and GnRH-R proteins. At 6 and 24 h, neither LA nor GA alone had an effect on gene expression. GnRH analogues alone or following E2 and/or P4 co-incubation for 24 h also had no effect on gene expression, but P4 significantly increased expression of CHMP1A.E2 + P4 treatment for 4 days, alone or followed by GA, had no effect, but E2 + P4 treatment followed by LA significantly decreased IGFBP-5 expression. The addition of 8-Br cAMP did not modify gene expression, with the exception of IGFBP-5 that was significantly increased. The GnRH analogues did not modify intracellular cAMP levels. We identified conserved EREs for OPN, CHMP1A, SNX7 and PSAP and PREs for SNX7. We conclude that GnRH analogues appear not to have major direct effects on gene expression of human endo-metrial epithelial cells in vitro. © The Author 2010. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oxfordjournals.org.

  9. BJ-1108, a 6-Amino-2,4,5-trimethylpyridin-3-ol analogue, regulates differentiation of Th1 and Th17 cells to ameliorate experimental autoimmune encephalomyelitis.

    Science.gov (United States)

    Kang, Youra; Timilshina, Maheshwor; Nam, Tae-Gyu; Jeong, Byeong-Seon; Chang, Jae-Hoon

    2017-02-28

    CD4 + T cells play an important role in the initiation of an immune response by providing help to other cells. Among the helper T subsets, interferon-γ (IFN-γ)-secreting T helper 1 (Th1) and IL-17-secreting T helper 17 (Th17) cells are indispensable for clearance of intracellular as well as extracellular pathogens. However, Th1 and Th17 cells are also associated with pathogenesis and contribute to the progression of multiple inflammatory conditions and autoimmune diseases. In the current study, we found that BJ-1108, a 6-aminopyridin-3-ol analogue, significantly inhibited Th1 and Th17 differentiation in vitro in a concentration-dependent manner, with no effect on proliferation or apoptosis of activated T cells. Moreover, BJ-1108 inhibited differentiation of Th1 and Th17 cells in ovalbumin (OVA)-specific OT II mice. A complete Freund's adjuvant (CFA)/OVA-induced inflammatory model revealed that BJ-1108 can reduce generation of proinflammatory Th1 and Th17 cells. Furthermore, in vivo studies showed that BJ-1108 delayed onset of disease and suppressed experimental autoimmune encephalomyelitis (EAE) disease progression by inhibiting differentiation of Th1 and Th17 cells. BJ-1108 treatment ameliorates inflammation and EAE by inhibiting Th1 and Th17 cells differentiation. Our findings suggest that BJ-1108 is a promising novel therapeutic agent for the treatment of inflammation and autoimmune disease.

  10. Survival of spermatogonial stem cells in the rat after split dose irradiation during LH-RH analogue treatment

    International Nuclear Information System (INIS)

    Kroonenburgh, M.J.P.G. van; Daal, W.A.J. van; Beck, J.L.; Vemer, H.M.; Rolland, R.

    1987-01-01

    A rat model has been created in which a single injection of an LH-RH analogue depot preparation (Zoladex, ICI 118630) produced a temporary interruption of the pituitary-gonadal axis. This effect applied during irradiation was investigated as a possible mechanism to protect the testis from radiation damage. A local testicular irradiation dose of 6.0 Gy was given either as a single dose or as a fractionated (2 x 3.0 Gy) dose at different time intervals ranging from 8 to 72 h. Stem cell survival was measured 11 weeks after irradiation by means of the repopulation index and the number of haploid cells (spermatids) measured by flow cytometry. Serum gonadotrophins and testosterone concentrations were measured to evaluate hormonal recovery. No significant differences were observed between serum concentrations of follicle-stimulating hormone (FSH), luteinizing hormone (LH) and testosterone and the duration of the fractionation interval. Stem cell survival was higher following fractionated irradiation in comparison with the single dose. For the 8 h interval an increase in recovery ratio was found, amounting to a factor of 5 of the single dose value. The fluctuating pattern of the recovery curves indicated changes in radiosensitivity of stem cells. The combination of hormonal inhibition of spermatogenesis and fractionated irradiation led to a decrease in the absolute numbers of stem cells. However, the stem cell recovery curves were identical to those seen without hormonal inhibition. It was concluded that hormonal pretreatment with Zoladex during split dose irradiation had no protective effect on stem cell survival. 37 refs.; 4 figs

  11. Synthesis and biological evaluation of febrifugine analogues.

    Science.gov (United States)

    Mai, Huong Doan Thi; Thanh, Giang Vo; Tran, Van Hieu; Vu, Van Nam; Vu, Van Loi; Le, Cong Vinh; Nguyen, Thuy Linh; Phi, Thi Dao; Truong, Bich Ngan; Chau, Van Minh; Pham, Van Cuong

    2014-12-01

    A series of febrifugine analogues were designed and synthesized. Antimalarial activity evaluation of the synthetic compounds indicated that these derivatives had a strong inhibition against both chloroquine-sensitive and -resistant Plasmodium falciparum parasites. Many of them were found to be more active than febrifugine hydrochloride. The tested analogues had also a significant cytotoxicity against four cancer cell lines (KB, MCF7, LU1 and HepG2). Among the synthetic analogues, two compounds 17b and 17h displayed a moderate cytotoxicity while they exhibited a remarkable antimalarial activity.

  12. A comparison of the ability of rilpivirine (TMC278 and selected analogues to inhibit clinically relevant HIV-1 reverse transcriptase mutants

    Directory of Open Access Journals (Sweden)

    Johnson Barry C

    2012-12-01

    Full Text Available Abstract Background The recently approved anti-AIDS drug rilpivirine (TMC278, Edurant is a nonnucleoside inhibitor (NNRTI that binds to reverse transcriptase (RT and allosterically blocks the chemical step of DNA synthesis. In contrast to earlier NNRTIs, rilpivirine retains potency against well-characterized, clinically relevant RT mutants. Many structural analogues of rilpivirine are described in the patent literature, but detailed analyses of their antiviral activities have not been published. This work addresses the ability of several of these analogues to inhibit the replication of wild-type (WT and drug-resistant HIV-1. Results We used a combination of structure activity relationships and X-ray crystallography to examine NNRTIs that are structurally related to rilpivirine to determine their ability to inhibit WT RT and several clinically relevant RT mutants. Several analogues showed broad activity with only modest losses of potency when challenged with drug-resistant viruses. Structural analyses (crystallography or modeling of several analogues whose potencies were reduced by RT mutations provide insight into why these compounds were less effective. Conclusions Subtle variations between compounds can lead to profound differences in their activities and resistance profiles. Compounds with larger substitutions replacing the pyrimidine and benzonitrile groups of rilpivirine, which reorient pocket residues, tend to lose more activity against the mutants we tested. These results provide a deeper understanding of how rilpivirine and related compounds interact with the NNRTI binding pocket and should facilitate development of novel inhibitors.

  13. Effect of Spermidine Analogues on Cell Growth of Escherichia coli Polyamine Requiring Mutant MA261.

    Directory of Open Access Journals (Sweden)

    Taketo Yoshida

    Full Text Available The effects of spermidine analogues [norspermidine (NSPD, 33, spermidine (SPD, 34, homospermidine (HSPD, 44 and aminopropylcadaverine (APCAD, 35] on cell growth were studied using Escherichia coli polyamine-requiring mutant MA261. Cell growth was compared at 32°C, 37°C, and 42°C. All four analogues were taken up mainly by the PotABCD spermidine-preferential uptake system. The degree of stimulation of cell growth at 32°C and 37°C was NSPD ≥ SPD ≥ HSPD > APCAD, and SPD ≥ HSPD ≥ NSPD > APCAD, respectively. However, at 42°C, it was HSPD » SPD > NSPD > APCAD. One reason for this is HSPD was taken up effectively compared with other triamines. In addition, since natural polyamines (triamines and teteraamines interact mainly with RNA, and the structure of RNA is more flexible at higher temperatures, HSPD probably stabilized RNA more tightly at 42°C. We have thus far found that 20 kinds of protein syntheses are stimulated by polyamines at the translational level. Among them, synthesis of OppA, RpoE and StpA was more strongly stimulated by HSPD at 42°C than at 37°C. Stabilization of the initiation region of oppA and rpoE mRNA was tighter by HSPD at 42°C than 37°C determined by circular dichroism (CD. The degree of polyamine stimulation of OppA, RpoE and StpA synthesis by NSPD, SPD and APCAD was smaller than that by HSPD at 42°C. Thus, the degree of stimulation of cell growth by spermidine analogues at the different temperatures is dependent on the stimulation of protein synthesis by some components of the polyamine modulon.

  14. Inhibition and Structure of Trichomonas vaginalis Purine Nucleoside Phosphorylase with Picomolar Transition State Analogues

    Energy Technology Data Exchange (ETDEWEB)

    Rinaldo-Matthis,A.; Wing, C.; Ghanem, M.; Deng, H.; Wu, P.; Gupta, A.; Tyler, P.; Evans, G.; Furneaux, R.; et al.

    2007-01-01

    Trichomonas vaginalis is a parasitic protozoan purine auxotroph possessing a unique purine salvage pathway consisting of a bacterial type purine nucleoside phosphorylase (PNP) and a purine nucleoside kinase. Thus, T. vaginalis PNP (TvPNP) functions in the reverse direction relative to the PNPs in other organisms. Immucillin-A (ImmA) and DADMe-Immucillin-A (DADMe-ImmA) are transition stte mimics of adenosine with geometric and electrostatic features that resemble early and late transition states of adenosine at the transition state stabilized by TvPNP. ImmA demonstrates slow-onset tight-binding inhibition with TvPNP, to give an equilibrium dissociation constant of 87 pM, an inhibitor release half-time of 17.2 min, and a K{sub m}/K{sub d} ratio of 70,100. DADMe-ImmA resembles a late ribooxacarbenium ion transition state for TvPNP to give a dissociation constant of 30 pM, an inhibitor release half-time of 64 min, and a K{sub m}/K{sub d} ratio of 203,300. The tight binding of DADMe-ImmA supports a late S{sub N}1 transition state. Despite their tight binding to TvPNP, ImmA and DADMe-ImmA are weak inhibitors of human and P. falciparum PNPs. The crystal structures of the TvPNP-ImmA{center_dot}PO{sub 4} and TvPNP{center_dot}DADMe-ImmA{center_dot}PO{sub 4} ternary complexes differ from previous structures with substrate anologues. The tight binding with DADMe-ImmA is in part due to a 2.7 {angstrom} ionic interaction between a PO{sub 4} oxygen and the N1 cation of the hydroxypyrrolidine and is weaker in the TvPNP{center_dot}ImmA{center_dot}PO{sub 4} structure at 3.5 {angstrom}. However, the TvPNP{center_dot}ImmA{center_dot}PO{sub 4} structure includes hydrogen bonds between the 2'-hydroxyl and the protein that are not present in TvPNP{center_dot}DADMe-ImmA{center_dot}PO{sub 4}. These structures explain why DADMe-ImmA binds tighter than ImmA. Immucillin-H is a 12 nM inhibitor of TvPNP but a 56 pM inhibitor of human PNP. And this difference is explained by isotope

  15. Inhibition of autophagy induced by proteasome inhibition increases cell death in human SHG-44 glioma cells.

    Science.gov (United States)

    Ge, Peng-Fei; Zhang, Ji-Zhou; Wang, Xiao-Fei; Meng, Fan-Kai; Li, Wen-Chen; Luan, Yong-Xin; Ling, Feng; Luo, Yi-Nan

    2009-07-01

    The ubiquitin-proteasome system (UPS) and lysosome-dependent macroautophagy (autophagy) are two major intracellular pathways for protein degradation. Recent studies suggest that proteasome inhibitors may reduce tumor growth and activate autophagy. Due to the dual roles of autophagy in tumor cell survival and death, the effect of autophagy on the destiny of glioma cells remains unclear. In this study, we sought to investigate whether inhibition of the proteasome can induce autophagy and the effects of autophagy on the fate of human SHG-44 glioma cells. The proteasome inhibitor MG-132 was used to induce autophagy in SHG-44 glioma cells, and the effect of autophagy on the survival of SHG-44 glioma cells was investigated using an autophagy inhibitor 3-MA. Cell viability was measured by MTT assay. Apoptosis and cell cycle were detected by flow cytometry. The expression of autophagy related proteins was determined by Western blot. MG-132 inhibited cell proliferation, induced cell death and cell cycle arrest at G(2)/M phase, and activated autophagy in SHG-44 glioma cells. The expression of autophagy-related Beclin-1 and LC3-I was significantly up-regulated and part of LC3-I was converted into LC3-II. However, when SHG-44 glioma cells were co-treated with MG-132 and 3-MA, the cells became less viable, but cell death and cell numbers at G(2)/M phase increased. Moreover, the accumulation of acidic vesicular organelles was decreased, the expression of Beclin-1 and LC3 was significantly down-regulated and the conversion of LC3-II from LC3-I was also inhibited. Inhibition of the proteasome can induce autophagy in human SHG-44 glioma cells, and inhibition of autophagy increases cell death. This discovery may shed new light on the effect of autophagy on modulating the fate of SHG-44 glioma cells.Acta Pharmacologica Sinica (2009) 30: 1046-1052; doi: 10.1038/aps.2009.71.

  16. Differential Reponses of Hematopoietic Stem and Progenitor Cells to mTOR Inhibition

    Directory of Open Access Journals (Sweden)

    Aimin Yang

    2015-01-01

    Full Text Available Abnormal activation of the mammalian target of rapamycin (mTOR signaling pathway has been observed in a variety of human cancers. Therefore, targeting of the mTOR pathway is an attractive strategy for cancer treatment and several mTOR inhibitors, including AZD8055 (AZD, a novel dual mTORC1/2 inhibitor, are currently in clinical trials. Although bone marrow (BM suppression is one of the primary side effects of anticancer drugs, it is not known if pharmacological inhibition of dual mTORC1/2 affects BM hematopoietic stem and progenitor cells (HSPCs function and plasticity. Here we report that dual inhibition of mTORC1/2 by AZD or its analogue (KU-63794 depletes mouse BM Lin−Sca-1+c-Kit+ cells in cultures via the induction of apoptotic cell death. Subsequent colony-forming unit (CFU assays revealed that inhibition of mTORC1/2 suppresses the clonogenic function of hematopoietic progenitor cells (HPCs in a dose-dependent manner. Surprisingly, we found that dual inhibition of mTORC1/2 markedly inhibits the growth of day-14 cobblestone area-forming cells (CAFCs but enhances the generation of day-35 CAFCs. Given the fact that day-14 and day-35 CAFCs are functional surrogates of HPCs and hematopoietic stem cells (HSCs, respectively, these results suggest that dual inhibition of mTORC1/2 may have distinct effects on HPCs versus HSCs.

  17. Cell Cycle Inhibition To Treat Sleeping Sickness

    Directory of Open Access Journals (Sweden)

    Conrad L. Epting

    2017-09-01

    Full Text Available African trypanosomiasis is caused by infection with the protozoan parasite Trypanosoma brucei. During infection, this pathogen divides rapidly to high density in the bloodstream of its mammalian host in a manner similar to that of leukemia. Like all eukaryotes, T. brucei has a cell cycle involving the de novo synthesis of DNA regulated by ribonucleotide reductase (RNR, which catalyzes the conversion of ribonucleotides into their deoxy form. As an essential enzyme for the cell cycle, RNR is a common target for cancer chemotherapy. We hypothesized that inhibition of RNR by genetic or pharmacological means would impair parasite growth in vitro and prolong the survival of infected animals. Our results demonstrate that RNR inhibition is highly effective in suppressing parasite growth both in vitro and in vivo. These results support drug discovery efforts targeting the cell cycle, not only for African trypanosomiasis but possibly also for other infections by eukaryotic pathogens.

  18. (−-Epigallocatechin 3-Gallate Synthetic Analogues Inhibit Fatty Acid Synthase and Show Anticancer Activity in Triple Negative Breast Cancer

    Directory of Open Access Journals (Sweden)

    Joan Crous-Masó

    2018-05-01

    Full Text Available (−-Epigallocatechin 3-gallate (EGCG is a natural polyphenol from green tea with reported anticancer activity and capacity to inhibit the lipogenic enzyme fatty acid synthase (FASN, which is overexpressed in several human carcinomas. To improve the pharmacological profile of EGCG, we previously developed a family of EGCG derivatives and the lead compounds G28, G37 and G56 were characterized in HER2-positive breast cancer cells overexpressing FASN. Here, diesters G28, G37 and G56 and two G28 derivatives, monoesters M1 and M2, were synthesized and assessed in vitro for their cytotoxic, FASN inhibition and apoptotic activities in MDA-MB-231 triple-negative breast cancer (TNBC cells. All compounds displayed moderate to high cytotoxicity and significantly blocked FASN activity, monoesters M1 and M2 being more potent inhibitors than diesters. Interestingly, G28, M1, and M2 also diminished FASN protein expression levels, but only monoesters M1 and M2 induced apoptosis. Our results indicate that FASN inhibition by such polyphenolic compounds could be a new strategy in TNBC treatment, and highlight the potential anticancer activities of monoesters. Thus, G28, G37, G56, and most importantly M1 and M2, are anticancer candidates (alone or in combination to be further characterized in vitro and in vivo.

  19. (-)-Epigallocatechin 3-Gallate Synthetic Analogues Inhibit Fatty Acid Synthase and Show Anticancer Activity in Triple Negative Breast Cancer.

    Science.gov (United States)

    Crous-Masó, Joan; Palomeras, Sònia; Relat, Joana; Camó, Cristina; Martínez-Garza, Úrsula; Planas, Marta; Feliu, Lidia; Puig, Teresa

    2018-05-11

    (-)-Epigallocatechin 3-gallate (EGCG) is a natural polyphenol from green tea with reported anticancer activity and capacity to inhibit the lipogenic enzyme fatty acid synthase (FASN), which is overexpressed in several human carcinomas. To improve the pharmacological profile of EGCG, we previously developed a family of EGCG derivatives and the lead compounds G28, G37 and G56 were characterized in HER2-positive breast cancer cells overexpressing FASN. Here, diesters G28, G37 and G56 and two G28 derivatives, monoesters M1 and M2, were synthesized and assessed in vitro for their cytotoxic, FASN inhibition and apoptotic activities in MDA-MB-231 triple-negative breast cancer (TNBC) cells. All compounds displayed moderate to high cytotoxicity and significantly blocked FASN activity, monoesters M1 and M2 being more potent inhibitors than diesters. Interestingly, G28, M1, and M2 also diminished FASN protein expression levels, but only monoesters M1 and M2 induced apoptosis. Our results indicate that FASN inhibition by such polyphenolic compounds could be a new strategy in TNBC treatment, and highlight the potential anticancer activities of monoesters. Thus, G28, G37, G56, and most importantly M1 and M2, are anticancer candidates (alone or in combination) to be further characterized in vitro and in vivo.

  20. Inhibition of Topoisomerase IIα and Induction of Apoptosis in Gastric Cancer Cells by 19-Triisopropyl Andrographolide

    Science.gov (United States)

    Monger, Adeep; Boonmuen, Nittaya; Suksen, Kanoknetr; Saeeng, Rungnapha; Kasemsuk, Teerapich; Piyachaturawat, Pawinee; Saengsawang, Witchuda; Chairoungdua, Arthit

    2017-10-26

    Gastric cancer is the most common cancer in Eastern Asia. Increasing chemoresistance and general systemic toxicities have complicated the current chemotherapy leading to an urgent need of more effective agents. The present study reported a potent DNA topoisomerase IIα inhibitory activity of an andrographolide analogue (19-triisopropyl andrographolide, analogue-6) in gastric cancer cells; MKN-45, and AGS cells. The analogue was potently cytotoxic to both gastric cancer cell lines with the half maximal inhibitory concentration (IC50 values) of 6.3±0.7 μM, and 1.7±0.05 μM at 48 h for MKN-45, and AGS cells, respectively. It was more potent than the parent andrographolide and the clinically used, etoposide with the IC50 values of >50 μM in MKN-45 and 11.3±2.9 μM in AGS cells for andrographolide and 28.5±4.4 μM in MKN-45 and 4.08±0.5 μM in AGS cells for etoposide. Analogue-6 at 2 μM significantly inhibited DNA topoisomerase IIα enzyme in AGS cells, induced DNA damage, activated cleaved PARP-1, and Caspase3 leading to late cellular apoptosis. Interestingly, the expression of tumor suppressor p53 was not activated. These results show the importance of 19-triisopropyl-andrographolide in its emerging selectivity to primary target on topoisomerase IIα enzyme, inducing DNA damage and apoptosis by p53- independent mechanism. Thereby, the results provide insights of the potential of 19-triisopropyl andrographolide as an anticancer agent for gastric cancer. The chemical transformation of andrographolide is a promising strategy in drug discovery of a novel class of anticancer drugs from bioactive natural products. Creative Commons Attribution License

  1. Proteome analysis demonstrates profound alterations in human dendritic cell nature by TX527, an analogue of vitamin D

    DEFF Research Database (Denmark)

    Ferreira, G. B.; van Etten, E.; Lage, K.

    2009-01-01

    Structural analogues of vitamin D have been put forward as therapeutic agents able to exploit the immunomodulatory effects of vitamin D, without its undesired calcemic side effects. We have demonstrated that TX527 affects dendritic cell (DC) maturation in vitro, resulting in the generation...... of a tolerogenic cell. In the present study, we aimed to explore the global protein changes induced by the analogue in immature DC (iDC) and mature human DC and to correlate them with alterations in DC morphology and function. Human CD14(+) monocytes were differentiated toward iDC or mature DCs, in the presence...

  2. Inhibition of S-adenosylmethionine decarboxylase and diamine oxidase activities by analogues of methylglyoxal bis(guanylhydrazone) and their cellular uptake during lymphocyte activation.

    Science.gov (United States)

    Jänne, J; Morris, D R

    1984-03-15

    Several congeners of methylglyoxal bis(guanylhydrazone) were tested for their ability to inhibit eukaryotic putrescine-activated S-adenosylmethionine decarboxylase (EC 4.1.1.50) and intestinal diamine oxidase (EC 1.4.3.6). All the compounds tested, namely methylglyoxal bis(guanylhydrazone), ethylglyoxal bis(guanylhydrazone), dimethylglyoxal bis(guanylhydrazone) and the di-N"-methyl derivative of methylglyoxal bis(guanylhydrazone), were strong inhibitors of both yeast and mouse liver adenosylmethionine decarboxylase activity in vitro. The enzyme from both sources was most powerfully inhibited by ethylglyoxal bis(guanylhydrazone). All the diguanidines likewise inhibited diamine oxidase activity in vitro. The maximum intracellular concentrations of the ethyl and dimethylated analogues achieved in activated lymphocytes were only about one-fifth of that of the parent compound. However, both derivatives appeared to utilize the polyamine-carrier system, as indicated by competition experiments with spermidine.

  3. Platelets Inhibit Migration of Canine Osteosarcoma Cells.

    Science.gov (United States)

    Bulla, S C; Badial, P R; Silva, R C; Lunsford, K; Bulla, C

    2017-01-01

    The interaction between platelets and tumour cells is important for tumour growth and metastasis. Thrombocytopenia or antiplatelet treatment negatively impact on cancer metastasis, demonstrating potentially important roles for platelets in tumour progression. To our knowledge, there is no information regarding the role of platelets in cancer progression in dogs. This study was designed to test whether canine platelets affected the migratory behaviour of three canine osteosarcoma cell lines and to give insights of molecular mechanisms. Intact platelets, platelet lysate and platelet releasate inhibited the migration of canine osteosarcoma cell lines. Addition of blood leucocytes to the platelet samples did not alter the inhibitory effect on migration. Platelet treatment also significantly downregulated the transcriptional levels of SNAI2 and TWIST1 genes. The interaction between canine platelets or molecules released during platelet activation and these tumour cell lines inhibits their migration, which suggests that canine platelets might antagonize metastasis of canine osteosarcoma. This effect is probably due to, at least in part, downregulation of genes related to epithelial-mesenchymal transition. Copyright © 2016. Published by Elsevier Ltd.

  4. MECHANISM OF ACTION OF ANTIBIOTICS WHICH INHIBIT SYNTHESIS OF BACTERIAL CELL WALL

    Directory of Open Access Journals (Sweden)

    Indira Mujezinović

    2013-03-01

    Full Text Available Bacterial cell possess a cell wall, which is a main difference from mammalian cells. Its basic function is to provide the strength of bacteria, keeps its shape and provides an unusually high internal osmotic pressure. Synthesis of (construction of bacterial cell wall occurs in at least three phases. All of these three phases can be influence by a variety of antibiotics in way to inhibit its synthesis. The most important drugs that act in this manner are ß-lactam antibiotics (penicillins, cephalosporins, cephamycins and other ß-lactams. They interfere with the synthesis of the bacterial cell wall peptidoglycan. After attachment to penicillin binding proteins (PBP on bacteria, they inhibit the transpeptidation enzyme that cross-links the peptide chain attached to the backbone of the peptidoglycan. The final bactericidal event is the inactivation of an inhibitor of autolytic enzymes in the cell wall, wich leads to lysis of the bacteria. Vancomycin inhibits the release of the building block unit from the carrier, thus preventing its addition to the growing end of the peptidoglycan. Cycloserine, which is a structural analogue of D-alanine, prevents the addition of the two terminal alanine residue to the initial tripeptide side-chain on N-acetylmuramic acid by competitive inhibition. Bacitracin interferes with the regeneration of the lipid carrier by blocking its dephosphorylation. Key words: bacterial cell wall, paptidoglycan, antibiotics, ß-lactams

  5. Evaluation of the cardiotoxicity of mitragynine and its analogues using human induced pluripotent stem cell-derived cardiomyocytes.

    Directory of Open Access Journals (Sweden)

    Jun Lu

    Full Text Available Mitragynine is a major bioactive compound of Kratom, which is derived from the leave extracts of Mitragyna speciosa Korth or Mitragyna speciosa (M. speciosa, a medicinal plant from South East Asia used legally in many countries as stimulant with opioid-like effects for the treatment of chronic pain and opioid-withdrawal symptoms. Fatal incidents with Mitragynine have been associated with cardiac arrest. In this study, we determined the cardiotoxicity of Mitragynine and other chemical constituents isolated using human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs.The rapid delayed rectifier potassium current (IKr, L-type Ca2+ current (ICa,L and action potential duration (APD were measured by whole cell patch-clamp. The expression of KCNH2 and cytotoxicity was determined by real-time PCR and Caspase activity measurements. After significant IKr suppression by Mitragynine (10 µM was confirmed in hERG-HEK cells, we systematically examined the effects of Mitragynine and other chemical constituents in hiPSC-CMs. Mitragynine, Paynantheine, Speciogynine and Speciociliatine, dosage-dependently (0.1∼100 µM suppressed IKr in hiPSC-CMs by 67%∼84% with IC50 ranged from 0.91 to 2.47 µM. Moreover, Mitragynine (10 µM significantly prolonged APD at 50 and 90% repolarization (APD50 and APD90 (439.0±11.6 vs. 585.2±45.5 ms and 536.0±22.6 vs. 705.9±46.1 ms, respectively and induced arrhythmia, without altering the L-type Ca2+ current. Neither the expression, and intracellular distribution of KCNH2/Kv11.1, nor the Caspase 3 activity were significantly affected by Mitragynine.Our study indicates that Mitragynine and its analogues may potentiate Torsade de Pointes through inhibition of IKr in human cardiomyocytes.

  6. An Analogue VLSI Implementation of the Meddis Inner Hair Cell Model

    Science.gov (United States)

    McEwan, Alistair; van Schaik, André

    2003-12-01

    The Meddis inner hair cell model is a widely accepted, but computationally intensive computer model of mammalian inner hair cell function. We have produced an analogue VLSI implementation of this model that operates in real time in the current domain by using translinear and log-domain circuits. The circuit has been fabricated on a chip and tested against the Meddis model for (a) rate level functions for onset and steady-state response, (b) recovery after masking, (c) additivity, (d) two-component adaptation, (e) phase locking, (f) recovery of spontaneous activity, and (g) computational efficiency. The advantage of this circuit, over other electronic inner hair cell models, is its nearly exact implementation of the Meddis model which can be tuned to behave similarly to the biological inner hair cell. This has important implications on our ability to simulate the auditory system in real time. Furthermore, the technique of mapping a mathematical model of first-order differential equations to a circuit of log-domain filters allows us to implement real-time neuromorphic signal processors for a host of models using the same approach.

  7. An Analogue VLSI Implementation of the Meddis Inner Hair Cell Model

    Directory of Open Access Journals (Sweden)

    Alistair McEwan

    2003-06-01

    Full Text Available The Meddis inner hair cell model is a widely accepted, but computationally intensive computer model of mammalian inner hair cell function. We have produced an analogue VLSI implementation of this model that operates in real time in the current domain by using translinear and log-domain circuits. The circuit has been fabricated on a chip and tested against the Meddis model for (a rate level functions for onset and steady-state response, (b recovery after masking, (c additivity, (d two-component adaptation, (e phase locking, (f recovery of spontaneous activity, and (g computational efficiency. The advantage of this circuit, over other electronic inner hair cell models, is its nearly exact implementation of the Meddis model which can be tuned to behave similarly to the biological inner hair cell. This has important implications on our ability to simulate the auditory system in real time. Furthermore, the technique of mapping a mathematical model of first-order differential equations to a circuit of log-domain filters allows us to implement real-time neuromorphic signal processors for a host of models using the same approach.

  8. Production of structured soy-based meat analogues using simple shear and heat in a Couette Cell

    NARCIS (Netherlands)

    Krintiras, G.A.; Gobel, T.W.; Goot, van der A.J.; Stefanidis, G.D.

    2015-01-01

    A Couette Cell device was employed to provide proof of concept for the production of structured meat analogues by application of simple shear flow and heat to a 31 wt% Soy Protein Isolate (SPI)–Wheat Gluten (WG) dispersion. Three relevant process parameters (temperature, time and rotation rate) were

  9. Do GnRH analogues directly affect human endometrial epithelial cell gene expression?

    KAUST Repository

    Zhang, Xiaomei; Bocca, Silvina Maria; Franchi, Anahí ; Anderson, Sandra; Kaur, Mandeep; Bajic, Vladimir B.; Oehninger, Sergio Carlos

    2010-01-01

    were: (i) to study the modulatory effect of GnRH analogues by RT-PCR [in the absence and presence of E2 and P4, and cyclic adenosine monophos-phate (cAMP)] on mRNA expression of genes modulated during the window of implantation in GnRH analogues

  10. Inhibiting cancer cell hallmark features through nuclear export inhibition.

    Science.gov (United States)

    Sun, Qingxiang; Chen, Xueqin; Zhou, Qiao; Burstein, Ezra; Yang, Shengyong; Jia, Da

    2016-01-01

    Treating cancer through inhibition of nuclear export is one of the best examples of basic research translation into clinical application. Nuclear export factor chromosomal region maintenance 1 (CRM1; Xpo1 and exportin-1) controls cellular localization and function of numerous proteins that are critical for the development of many cancer hallmarks. The diverse actions of CRM1 are likely to explain the broad ranging anti-cancer potency of CRM1 inhibitors observed in pre-clinical studies and/or clinical trials (phase I-III) on both advanced-stage solid and hematological tumors. In this review, we compare and contrast the mechanisms of action of different CRM1 inhibitors, and discuss the potential benefit of unexplored non-covalent CRM1 inhibitors. This emerging field has uncovered that nuclear export inhibition is well poised as an attractive target towards low-toxicity broad-spectrum potent anti-cancer therapy.

  11. Inhibition of Procarcinogen Activating Enzyme CYP1A2 Activity and Free Radical Formation by Caffeic Acid and its Amide Analogues.

    Science.gov (United States)

    Narongchai, Paitoon; Niwatananun, Kanokporn; Narongchai, Siripun; Kusirisin, Winthana; Jaikang, Churdsak

    2016-01-01

    Caffeic acid (CAF) and its amide analogues, ethyl 1-(3',4'-dihydroxyphenyl) propen amide (EDPA), phenethyl 1-(3',4'-dihydroxyphenyl) propen amide (PEDPA), phenmethyl 1- (3',4'-dihydroxyphenyl) propen amide (PMDPA) and octyl 1-(3',4'-dihydroxyphenyl) propen amide (ODPA) were investigated for the inhibition of procarcinogen activating enzyme. CYP1A2 and scavenging activity on formation of nitric oxide, superoxide anion, DPPH radical and hydroxyl radical. It was found that they inhibited CYP1A2 enzyme by uncompetitive inhibition. Apparent Ki values of CAF, EDPA, PEDPA, PMDPA and ODPA were 0.59, 0.39, 0.45, 0.75 and 0.80 µM, respectively suggesting potent inhibitors of CYP1A2. Moreover, they potentially scavenged nitric oxide radical with IC 50 values of 0.12, 0.22, 0.28, 0.22 and 0.51 mM, respectively. The IC50 values of superoxide anion scavenging were 0.20, 0.22, 0.44, 2.18 and 2.50 mM, respectively. 1, 1- diphenyl-2- picrylhydrazyl (DPPH) radical-scavenging ability, shown as IC50 values, were 0.41, 0.29, 0.30, 0.89 and 0.84 mM, respectively. Moreover, the hydroxyl radical scavenging in vitro model was shown as IC50 values of 23.22, 21.06, 17.10, 17.21 and 15.81 µM, respectively. From our results, caffeic acid and its amide analogues are in vitro inhibitors of human CYP1A2 catalytic activity and free radical formation. They may be useful to be developed as potential chemopreventive agents that block CYP1A2-mediated chemical carcinogenesis.

  12. Menadione inhibits MIBG uptake in two neuroendocrine cell lines

    NARCIS (Netherlands)

    Cornelissen, J.; Tytgat, G. A.; van den Brug, M.; van Kuilenburg, A. B.; Voûte, P. A.; van Gennip, A. H.

    1997-01-01

    In this paper we report on our studies of the effect of menadione on the uptake of MIBG in the neuroendocrine cell lines PC12 and SK-N-SH. Menadione inhibits the uptake of MIBG in both cell lines in a dose-dependent manner. Inhibition of MIBG uptake is most pronounced in the PC12 cell line.

  13. Experimental and Theoretical Studies of the Structures and Interactions of Vancomycin Antibiotics with Cell Wall Analogues

    International Nuclear Information System (INIS)

    Yang, Zhibo; Vorpagel, Erich R.; Laskin, Julia

    2008-01-01

    Surface-induced dissociation (SID) of the singly protonated complex of vancomycin antibiotic with cell wall peptide analogue (N α , N # var e psilon#-diacetyl-L-Lys-D-Ala-D-Ala) was studied using a 6 T Fourier Transform Ion Cyclotron Resonance Mass Spectrometer (FT-ICR MS) specially configured for SID experiments. The binding energy between the vancomycin and the peptide was obtained from the RRKM modeling of the time- and energy resolved fragmentation efficiency curves (TFECs) of the precursor ion and its fragments. Electronic structure calculations of the geometries, proton affinities and binding energies were performed for several model systems including vancomycin (V), vancomycin aglycon (VA), N α , N # var e psilon#-diacetyl-L-Lys-D-Ala-D-Ala, and non-covalent complexes of VA with N-acetyl-D-Ala-D-Ala and N α , N # var e psilon#-diacetyl-L-Lys-D-Ala-D-Ala at the B3LYP/6-31G(d) level of theory. Comparison between the experimental and computational results suggests that the most probable structure of the complex observed in our experiments corresponds to the neutral peptide bound to the vancomycin protonated at the secondary amino group of the N-methyl-leucine residue. The experimental binding energy of 30.9 ± 1.8 kcal/mol is in good agreement with the binding energy of 29.3 ± 2.5 kcal/mol calculated for the model system representing the preferred structure of the complex

  14. Hypoglycemic and beta cell protective effects of andrographolide analogue for diabetes treatment

    Directory of Open Access Journals (Sweden)

    Larrick James W

    2009-07-01

    Full Text Available Abstract Background While all anti-diabetic agents can decrease blood glucose level directly or indirectly, few are able to protect and preserve both pancreatic beta cell mass and their insulin-secreting functions. Thus, there is an urgent need to find an agent or combination of agents that can lower blood glucose and preserve pancreatic beta cells at the same time. Herein, we report a dual-functional andrographolide-lipoic acid conjugate (AL-1. The anti-diabetic and beta cell protective activities of this novel andrographolide-lipoic acid conjugate were investigated. Methods In alloxan-treated mice (a model of type 1 diabetes, drugs were administered orally once daily for 6 days post-alloxan treatment. Fasting blood glucose and serum insulin were determined. Pathologic and immunohistochemical analysis of pancreatic islets were performed. Translocation of glucose transporter subtype 4 in soleus muscle was detected by western blot. In RIN-m cells in vitro, the effect of AL-1 on H2O2-induced damage and reactive oxidative species production stimulated by high glucose and glibenclamide were measured. Inhibition of nuclear factor kappa B (NF-κB activation induced by IL-1β and IFN-γ was investigated. Results In alloxan-induced diabetic mouse model, AL-1 lowered blood glucose, increased insulin and prevented loss of beta cells and their dysfunction, stimulated glucose transport protein subtype 4 (GLUT4 membrane translocation in soleus muscles. Pretreatment of RIN-m cells with AL-1 prevented H2O2-induced cellular damage, quenched glucose and glibenclamide-stimulated reactive oxidative species production, and inhibited cytokine-stimulated NF-κB activation. Conclusion We have demonstrated that AL-1 had both hypoglycemic and beta cell protective effects which translated into antioxidant and NF-κB inhibitory activity. AL-1 is a potential new anti-diabetic agent.

  15. The mode of inhibition of the Na+-K+ pump activity in mast cells by calcium

    DEFF Research Database (Denmark)

    Knudsen, T; Johansen, Torben

    1989-01-01

    , and hence the pump activity. This hypothesis is supported by the stimulation of pump activity produced by monensin, which is not inhibited by calcium. The enhancement of pump activity after exposure of calcium-deprived cells to EGTA might be the result of a further increase in the sodium permeability......1 The inhibition by calcium of the Na(+)-K+ pump in the plasma membrane of rat peritoneal mast cells was studied in pure populations of the cells by measuring the ouabain-sensitive uptake of the radioactive potassium analogue, 86rubidium (86Rb+). 2 Exposure of the cells to calcium induced a time......- and concentration-dependent decrease in the ouabain-sensitive K+(86Rb+)-uptake of the cells without influencing the ouabain-resistant uptake. The development of the inhibition required the presence of potassium in the medium in the millimolar range (1.5-8.0 mM), and it did not occur at a concentration of potassium...

  16. Protective activity of a novel resveratrol analogue, HS-1793, against DNA damage in 137Cs-irradiated CHO-K1 cells

    International Nuclear Information System (INIS)

    Jeong, Min Ho; Jo, Young Rae; Yang, Kwang Mo; Jeong, Dong Hyeok; Lee, Chang Geun; Oh, Su Jung; Jeong, Soo Kyung; Jo, Wol Soon; Lee, Ki Won

    2014-01-01

    Resveratrol has received considerable attention as a polyphenol with anti-oxidant, anti-carcinogenic, and anti-inflammatory effects. Radiation is an important component of therapy for a wide range of malignant conditions. However, it causes damage to normal cells and, hence, can result in adverse side effects. This study was conducted to examine whether HS-1793, a novel resveratrol analogue free from the restriction of metabolic instability and the high dose requirement of resveratrol, induces a protective effect against radiation-induced DNA damage. HS-1793 effectively scavenged free radicals and inhibited radiation-induced plasmid DNA strand breaks in an in vitro assay. HS-1793 significantly decreased reactive oxygen species and cellular DNA damage in 2 Gy-irradiated Chinese hamster ovary (CHO)-K1 cells. In addition, HS-1793 dose-dependently reduced the levels of phosphorylated H2AX in irradiated CHO-K1 cells. These results indicate that HS-1793 has chemical radioprotective activity. Glutathione levels and superoxide dismutase activity in irradiated CHO-K1 cells increased significantly following HS-1793 treatment. The enhanced biological anti-oxidant activity and chemical radioprotective activity of HS-1793 maintained survival of irradiated CHO-K1 cells in a clonogenic assay. Therefore, HS-1793 may be of value as a radioprotector to protect healthy tissue surrounding tumor cells during radiotherapy to obtain better tumor control with a higher dose. (author)

  17. Identification of Electronic and Structural Descriptors of Adenosine Analogues Related to Inhibition of Leishmanial Glyceraldehyde-3-Phosphate Dehydrogenase

    Directory of Open Access Journals (Sweden)

    Norka B. H. Lozano

    2013-04-01

    Full Text Available Quantitative structure–activity relationship (QSAR studies were performed in order to identify molecular features responsible for the antileishmanial activity of 61 adenosine analogues acting as inhibitors of the enzyme glyceraldehyde 3-phosphate dehydrogenase of Leishmania mexicana (LmGAPDH. Density functional theory (DFT was employed to calculate quantum-chemical descriptors, while several structural descriptors were generated with Dragon 5.4. Variable selection was undertaken with the ordered predictor selection (OPS algorithm, which provided a set with the most relevant descriptors to perform PLS, PCR and MLR regressions. Reliable and predictive models were obtained, as attested by their high correlation coefficients, as well as the agreement between predicted and experimental values for an external test set. Additional validation procedures were carried out, demonstrating that robust models were developed, providing helpful tools for the optimization of the antileishmanial activity of adenosine compounds.

  18. Analogue Gravity

    Directory of Open Access Journals (Sweden)

    Barceló Carlos

    2005-12-01

    Full Text Available Analogue models of (and for gravity have a long and distinguished history dating back to the earliest years of general relativity. In this review article we will discuss the history, aims, results, and future prospects for the various analogue models. We start the discussion by presenting a particularly simple example of an analogue model, before exploring the rich history and complex tapestry of models discussed in the literature. The last decade in particular has seen a remarkable and sustained development of analogue gravity ideas, leading to some hundreds of published articles, a workshop, two books, and this review article. Future prospects for the analogue gravity programme also look promising, both on the experimental front (where technology is rapidly advancing and on the theoretical front (where variants of analogue models can be used as a springboard for radical attacks on the problem of quantum gravity.

  19. Structural bisphenol analogues differentially target steroidogenesis in murine MA-10 Leydig cells as well as the glucocorticoid receptor.

    Science.gov (United States)

    Roelofs, Maarke J E; van den Berg, Martin; Bovee, Toine F H; Piersma, Aldert H; van Duursen, Majorie B M

    2015-03-02

    Although much information on the endocrine activity of bisphenol A (BPA) is available, a proper human hazard assessment of analogues that are believed to have a less harmful toxicity profile is lacking. Here the possible effects of BPA, bisphenol F (BPF), bisphenol S (BPS), as well as the brominated structural analogue and widely used flame retardant tetrabromobisphenol A (TBBPA) on human glucocorticoid and androgen receptor (GR and AR) activation were assessed. BPA, BPF, and TBBPA showed clear GR and AR antagonism with IC50 values of 67 μM, 60 μM, and 22 nM for GR, and 39 μM, 20 μM, and 982 nM for AR, respectively, whereas BPS did not affect receptor activity. In addition, murine MA-10 Leydig cells exposed to the bisphenol analogues were assessed for changes in secreted steroid hormone levels. Testicular steroidogenesis was altered by all bisphenol analogues tested. TBBPA effects were more directed towards the male end products and induced testosterone synthesis, while BPF and BPS predominantly increased the levels of progestagens that are formed in the beginning of the steroidogenic pathway. The MA-10 Leydig cell assay shows added value over the widely used H295R steroidogenesis assay because of its fetal-like characteristics and specificity for the physiologically more relevant testicular Δ4 steroidogenic pathway. Therefore, adding an in vitro assay covering fetal testicular steroidogenesis, such as the MA-10 cell line, to the panel of tests used to screen potential endocrine disruptors, is highly recommendable. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  20. The role of outcome inhibition in interference between outcomes: a contingency-learning analogue of retrieval-induced forgetting.

    Science.gov (United States)

    Vadillo, Miguel A; Orgaz, Cristina; Luque, David; Cobos, Pedro L; López, Francisco J; Matute, Helena

    2013-05-01

    Current associative theories of contingency learning assume that inhibitory learning plays a part in the interference between outcomes. However, it is unclear whether this inhibitory learning results in the inhibition of the outcome representation or whether it simply counteracts previous excitatory learning so that the outcome representation is neither activated nor inhibited. Additionally, these models tend to conceptualize inhibition as a relatively transient and cue-dependent state. However, research on retrieval-induced forgetting suggests that the inhibition of representations is a real process that can be relatively independent of the retrieval cue used to access the inhibited information. Consistent with this alternative view, we found that interference between outcomes reduces the retrievability of the target outcome even when the outcome is associated with a novel (non-inhibitory) cue. This result has important theoretical implications for associative models of interference and shows that the empirical facts and theories developed in studies of retrieval-induced forgetting might be relevant in contingency learning and vice versa. © 2012 The British Psychological Society.

  1. Arctigenin preferentially induces tumor cell death under glucose deprivation by inhibiting cellular energy metabolism.

    Science.gov (United States)

    Gu, Yuan; Qi, Chunting; Sun, Xiaoxiao; Ma, Xiuquan; Zhang, Haohao; Hu, Lihong; Yuan, Junying; Yu, Qiang

    2012-08-15

    Selectively eradicating cancer cells with minimum adverse effects on normal cells is a major challenge in the development of anticancer therapy. We hypothesize that nutrient-limiting conditions frequently encountered by cancer cells in poorly vascularized solid tumors might provide an opportunity for developing selective therapy. In this study, we investigated the function and molecular mechanisms of a natural compound, arctigenin, in regulating tumor cell growth. We demonstrated that arctigenin selectively promoted glucose-starved A549 tumor cells to undergo necrosis by inhibiting mitochondrial respiration. In doing so, arctigenin elevated cellular level of reactive oxygen species (ROS) and blocked cellular energy metabolism in the glucose-starved tumor cells. We also demonstrated that cellular ROS generation was caused by intracellular ATP depletion and played an essential role in the arctigenin-induced tumor cell death under the glucose-limiting condition. Furthermore, we combined arctigenin with the glucose analogue 2-deoxyglucose (2DG) and examined their effects on tumor cell growth. Interestingly, this combination displayed preferential cell-death inducing activity against tumor cells compared to normal cells. Hence, we propose that the combination of arctigenin and 2DG may represent a promising new cancer therapy with minimal normal tissue toxicity. Crown Copyright © 2012. Published by Elsevier Inc. All rights reserved.

  2. Paeoniflorin inhibits cell growth and induces cell cycle arrest through inhibition of FoxM1 in colorectal cancer cells.

    Science.gov (United States)

    Yue, Meng; Li, Shiquan; Yan, Guoqiang; Li, Chenyao; Kang, Zhenhua

    2018-01-01

    Paeoniflorin (PF) exhibits tumor suppressive functions in a variety of human cancers. However, the function of PF and molecular mechanism in colorectal cancer are elusive. In the present study, we investigated whether PF could exert its antiproliferative activity, anti-migration, and anti-invasive function in colorectal cancer cells. We found that PF inhibited cell growth and induced apoptosis and blocked cell cycle progression in the G0/G1 phase in colorectal cancer cells. Moreover, we found that PF suppressed cell migration and invasion in colorectal cancer cells. FoxM1 has been reported to play an important oncogenic role in human cancers. We also determine whether PF inhibited the expression of FoxM1, leading to its anti-cancer activity. We found that PF treatment in colorectal cancer cells resulted in down-regulation of FoxM1. The rescue experiments showed that overexpression of FoxM1 abrogated the tumor suppressive function induced by PF treatment. Notably, depletion of FoxM1 promoted the anti-tumor activity of PF in colorectal cancer cells. Therefore, inhibition of FoxM1 could participate in the anti-tumor activity of PF in colorectal cancer cells.

  3. Inhibition of microbial β-N-acetylhexosaminidases by 4-deoxy- and galacto-analogues of NAG-thiazoline

    Czech Academy of Sciences Publication Activity Database

    Krejzová, Jana; Ježová-Kalachová, Lubica; Šimon, Petr; Pelantová, Helena; Slámová, Kristýna; Křen, Vladimír

    2014-01-01

    Roč. 24, č. 22 (2014), s. 5321-5323 ISSN 0960-894X R&D Projects: GA ČR(CZ) GAP207/11/0629; GA MŠk(CZ) 7E11011 Institutional support: RVO:61388971 Keywords : NAG-thiazoline * enzyme inhibition Subject RIV: CE - Biochemistry Impact factor: 2.420, year: 2014

  4. Biological effects of a de novo designed myxoma virus peptide analogue: evaluation of cytotoxicity on tumor cells.

    Directory of Open Access Journals (Sweden)

    Taghrid S Istivan

    Full Text Available BACKGROUND: The Resonant Recognition Model (RRM is a physico-mathematical model that interprets protein sequence linear information using digital signal processing methods. In this study the RRM concept was employed for structure-function analysis of myxoma virus (MV proteins and the design of a short bioactive therapeutic peptide with MV-like antitumor/cytotoxic activity. METHODOLOGY/PRINCIPAL FINDINGS: The analogue RRM-MV was designed by RRM as a linear 18 aa 2.3 kDa peptide. The biological activity of this computationally designed peptide analogue against cancer and normal cell lines was investigated. The cellular cytotoxicity effects were confirmed by confocal immunofluorescence microscopy, by measuring the levels of cytoplasmic lactate dehydrogenase (LDH and by Prestoblue cell viability assay for up to 72 hours in peptide treated and non-treated cell cultures. Our results revealed that RRM-MV induced a significant dose and time-dependent cytotoxic effect on murine and human cancer cell lines. Yet, when normal murine cell lines were similarly treated with RRM-MV, no cytotoxic effects were observed. Furthermore, the non-bioactive RRM designed peptide RRM-C produced negligible cytotoxic effects on these cancer and normal cell lines when used at similar concentrations. The presence/absence of phosphorylated Akt activity in B16F0 mouse melanoma cells was assessed to indicate the possible apoptosis signalling pathway that could be affected by the peptide treatment. So far, Akt activity did not seem to be significantly affected by RRM-MV as is the case for the original viral protein. CONCLUSIONS/SIGNIFICANCE: Our findings indicate the successful application of the RRM concept to design a bioactive peptide analogue (RRM-MV with cytotoxic effects on tumor cells only. This 2.345 kDa peptide analogue to a 49 kDa viral protein may be suitable to be developed as a potential cancer therapeutic. These results also open a new direction to the rational

  5. Analogue Gravity

    Directory of Open Access Journals (Sweden)

    Carlos Barceló

    2011-05-01

    Full Text Available Analogue gravity is a research programme which investigates analogues of general relativistic gravitational fields within other physical systems, typically but not exclusively condensed matter systems, with the aim of gaining new insights into their corresponding problems. Analogue models of (and for gravity have a long and distinguished history dating back to the earliest years of general relativity. In this review article we will discuss the history, aims, results, and future prospects for the various analogue models. We start the discussion by presenting a particularly simple example of an analogue model, before exploring the rich history and complex tapestry of models discussed in the literature. The last decade in particular has seen a remarkable and sustained development of analogue gravity ideas, leading to some hundreds of published articles, a workshop, two books, and this review article. Future prospects for the analogue gravity programme also look promising, both on the experimental front (where technology is rapidly advancing and on the theoretical front (where variants of analogue models can be used as a springboard for radical attacks on the problem of quantum gravity.

  6. The role of monocytes and T cells in 1,25-dihydroxyvitamin D3 mediated inhibition of B cell function in vitro

    DEFF Research Database (Denmark)

    Müller, K; Heilmann, C; Poulsen, L K

    1991-01-01

    1,25-Dihydroxyvitamin D3 (1,25-(OH)2D3) inhibits immunoglobulin production by human mononuclear cells (MNC) in vitro. The present study was undertaken to evaluate the role of T cells and monocytes in 1,25-(OH)2D3 induced suppression of B cell functions. The synthetic vitamin D3 analogue MC 903...... was examined in parallel. 1,25-(OH)2D3 and MC 903 showed a dose-related inhibition of IgM, IgG and IgA plaque-forming cells in poke-weed mitogen (PWM) activated cultures of MNC. This effect was most likely mediated through impairment of T cell and monocyte functions. First, the inhibitory effect was seen after...

  7. Semisynthesis of SY-1 for investigation of breast cancer stem cell selectivity of C-ring-modified salinomycin analogues.

    Science.gov (United States)

    Huang, Xiaoli; Borgström, Björn; Månsson, Linda; Persson, Lo; Oredsson, Stina; Hegardt, Cecilia; Strand, Daniel

    2014-07-18

    Salinomycin, a naturally occurring polyether ionophore was recently found to selectively reduce the proportion of CD44(+)/CD24(-) cells, a phenotype associated with breast cancer stem cells. Subsequent studies from our group showed that chemical modification of the allylic C20 hydroxyl of salinomycin, located at the C-ring, can enhance the activity of derivatives against breast cancer cells over 5-fold compared to the native structure. Access to C-ring-modified salinomycin analogues is thus of interest from both a mechanistic and a synthetic perspective. Here, we report efficient strategies for gram scale synthesis of the natural product SY-1 (20-deoxy salinomycin), and a saturated analogue, 18,19-dihydro SY-1, for a comparative in vitro investigation of the biological profiles of these compounds with that of salinomycin. Across several assays, the deoxygenated structures required higher concentrations to elicit similar cellular responses to that of salinomycin. Similarly to salinomycin, SY-1 or 18,19-dihydro SY-1 treatment was found to reduce the proportion of CD44(+)/CD24(-) cells with essentially complete selectivity up to ∼IC25. Importantly, the proportion of CD44(+)/CD24(-) cells showed a pronounced U-shaped dose response curve for salinomycin and its derivatives, but not for paclitaxel. The concentration for maximum response in this assay followed differences in IC50 for salinomycin and its analogues, which emphasizes the importance of taking concentration dependence into account when comparing effects on the CD44(+)/CD24(-) phenotype. Small differences in the global conformation within the triad of compounds investigated together with differences in activity across assays emphasize the importance of substitution at C20 for the activity of salinomycin and its derivatives.

  8. Piracetam and TRH analogues antagonise inhibition by barbiturates, diazepam, melatonin and galanin of human erythrocyte D-glucose transport

    OpenAIRE

    Naftalin, Richard J; Cunningham, Philip; Afzal-Ahmed, Iram

    2004-01-01

    Nootropic drugs increase glucose uptake into anaesthetised brain and into Alzheimer's diseased brain. Thyrotropin-releasing hormone, TRH, which has a chemical structure similar to nootropics increases cerebellar uptake of glucose in murine rolling ataxia. This paper shows that nootropic drugs like piracetam (2-oxo 1 pyrrolidine acetamide) and levetiracetam and neuropeptides like TRH antagonise the inhibition of glucose transport by barbiturates, diazepam, melatonin and endogenous neuropeptide...

  9. Mullerian Inhibiting Substances (MIS) Augments IFN-gamma Mediated Inhibition of Breast Cancer Cell Growth

    National Research Council Canada - National Science Library

    Gupta, Vandana

    2006-01-01

    MIS is a member of the TGF family. The purpose of this study is to test the hypothesis that MIS and IFN-gamma might be more effective in the inhibition of breast cancer cell growth than either agent alone...

  10. Mullerian Inhibiting Substance (MIS) Augments IFN-gamma Mediated Inhibition of Breast Cancer Cell Growth

    National Research Council Canada - National Science Library

    Gupta, Vandana

    2004-01-01

    Mullerian Inhibiting Substance (MIS), a member of the TGFB family regulates growth, differentiation, and apoptosis in many cell types In the male embryo, MIS causes regression of the Mullerian duct...

  11. Methylglyoxal-bis(guanylhydrazone), a polyamine analogue, sensitized γ-radiation-induced cell death in HL-60 leukemia cells Sensitizing effect of MGBG on γ-radiation-induced cell death.

    Science.gov (United States)

    Kim, Jin Sik; Lee, Jin; Chung, Hai Won; Choi, Han; Paik, Sang Gi; Kim, In Gyu

    2006-09-01

    Methylglyoxal-bis(guanylhydrazone) (MGBG), a polyamine analogue, has been known to inhibit the biosynthesis of polyamines, which are important in cell proliferation. We showed that MGBG treatment significantly affected γ-radiation-induced cell cycle transition (G(1)/G(0)→S→G(2)/M) and thus γ-radiation-induced cell death. As determined by micronuclei and comet assay, we showed that it sensitized the cytotoxic effect induced by γ-radiation. One of the reasons is that polyamine depletion by MGBG treatment did not effectively protect against the chemical (OH) or physical damage to DNA caused by γ-radiation. Through in vitro experiment, we confirmed that DNA strand breaks induced by γ-radiation was prevented more effectively in the presence of polyamines (spermine and spermidine) than in the absence of polyamines. MGBG also blocks the cell cycle transition caused by γ-radiation (G(2) arrest), which helps protect cells by allowing time for DNA repair before entry into mitosis or apoptosis, via the down regulation of cyclin D1, which mediates the transition from G(1) to S phase of cell cycle, and ataxia telangiectasia mutated, which is involved in the DNA sensing, repair and cell cycle check point. Therefore, the abrogation of G(2) arrest sensitizes cells to the effect of γ-radiation. As a result, γ-radiation-induced cell death increased by about 2.5-3.0-fold in cells treated with MGBG. However, exogenous spermidine supplement partially relieved this γ-radiation-induced cytotoxicity and cell death. These findings suggest a potentially therapeutic strategy for increasing the cytotoxic efficacy of γ-radiation.

  12. Hyperoxia Inhibits T Cell Activation in Mice

    Science.gov (United States)

    Hughes-Fulford, M.; Meissler, J.; Aguayo, E. T.; Globus, R.; Aguado, J.; Candelario, T.

    2013-02-01

    , spleens were removed and the splenocytes were isolated and kept as individual biological samples. We have also examined transcription factors (JASPAR) and pathways of the immune system to help us understand the mechanism of regulation. Results: Our recent mouse immunology experiment aboard STS-131 suggests that the early T cell immune response was inhibited in animals that have been exposed to spaceflight, even 24 hours after return to earth. Moreover, recent experiments in hyperoxic mice show that many of the same genes involved in early T cell activation were altered. Specifically, expression of IL-2Rα, Cxcl2, TNFα, FGF2, LTA and BCL2 genes are dysregulated in mice exposed to hyperoxia. Conclusions: If these hyperoxia-induced changes of gene expression in early T cell activation are additive to the changes seen in the microgravity of spaceflight, there could be an increased infection risk to EVA astronauts, which should be addressed prior to conducting a Mars or other long-term mission.

  13. Agnus castus extracts inhibit prolactin secretion of rat pituitary cells.

    Science.gov (United States)

    Sliutz, G; Speiser, P; Schultz, A M; Spona, J; Zeillinger, R

    1993-05-01

    In our studies on prolactin inhibition by plant extracts we focused on the effects of extracts of Vitex agnus castus and its preparations on rat pituitary cells under basal and stimulated conditions in primary cell culture. Both extracts from Vitex agnus castus as well as synthetic dopamine agonists (Lisuride) significantly inhibit basal as well as TRH-stimulated prolactin secretion of rat pituitary cells in vitro and as a consequence inhibition of prolactin secretion could be blocked by adding a dopamine receptor blocker. Therefore because of its dopaminergic effect Agnus castus could be considered as an efficient alternative phytotherapeutic drug in the treatment of slight hyperprolactinaemia.

  14. Hili Inhibits HIV Replication in Activated T Cells.

    Science.gov (United States)

    Peterlin, B Matija; Liu, Pingyang; Wang, Xiaoyun; Cary, Daniele; Shao, Wei; Leoz, Marie; Hong, Tian; Pan, Tao; Fujinaga, Koh

    2017-06-01

    P-element-induced wimpy-like (Piwil) proteins restrict the replication of mobile genetic elements in the germ line. They are also expressed in many transformed cell lines. In this study, we discovered that the human Piwil 2 (Hili) protein can also inhibit HIV replication, especially in activated CD4 + T cells that are the preferred target cells for this virus in the infected host. Although resting cells did not express Hili, its expression was rapidly induced following T cell activation. In these cells and transformed cell lines, depletion of Hili increased levels of viral proteins and new viral particles. Further studies revealed that Hili binds to tRNA. Some of the tRNAs represent rare tRNA species, whose codons are overrepresented in the viral genome. Targeting tRNA Arg (UCU) with an antisense oligonucleotide replicated effects of Hili and also inhibited HIV replication. Finally, Hili also inhibited the retrotransposition of the endogenous intracysternal A particle (IAP) by a similar mechanism. Thus, Hili joins a list of host proteins that inhibit the replication of HIV and other mobile genetic elements. IMPORTANCE Piwil proteins inhibit the movement of mobile genetic elements in the germ line. In their absence, sperm does not form and male mice are sterile. This inhibition is thought to occur via small Piwi-interacting RNAs (piRNAs). However, in some species and in human somatic cells, Piwil proteins bind primarily to tRNA. In this report, we demonstrate that human Piwil proteins, especially Hili, not only bind to select tRNA species, including rare tRNAs, but also inhibit HIV replication. Importantly, T cell activation induces the expression of Hili in CD4 + T cells. Since Hili also inhibited the movement of an endogenous retrovirus (IAP), our finding shed new light on this intracellular resistance to exogenous and endogenous retroviruses as well as other mobile genetic elements. Copyright © 2017 American Society for Microbiology.

  15. Inhibition of brain tumor cell proliferation by alternating electric fields

    International Nuclear Information System (INIS)

    Jeong, Hyesun; Oh, Seung-ick; Hong, Sunghoi; Sung, Jiwon; Jeong, Seonghoon; Yoon, Myonggeun; Koh, Eui Kwan

    2014-01-01

    This study was designed to investigate the mechanism by which electric fields affect cell function, and to determine the optimal conditions for electric field inhibition of cancer cell proliferation. Low-intensity (<2 V/cm) and intermediate-frequency (100–300 kHz) alternating electric fields were applied to glioblastoma cell lines. These electric fields inhibited cell proliferation by inducing cell cycle arrest and abnormal mitosis due to the malformation of microtubules. These effects were significantly dependent on the intensity and frequency of applied electric fields

  16. Inhibition of brain tumor cell proliferation by alternating electric fields

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Hyesun; Oh, Seung-ick; Hong, Sunghoi, E-mail: shong21@korea.ac.kr, E-mail: radioyoon@korea.ac.kr [School of Biosystem and Biomedical Science, Korea University, Seoul 136-703 (Korea, Republic of); Sung, Jiwon; Jeong, Seonghoon; Yoon, Myonggeun, E-mail: shong21@korea.ac.kr, E-mail: radioyoon@korea.ac.kr [Department of Bio-convergence Engineering, Korea University, Seoul 136-703 (Korea, Republic of); Koh, Eui Kwan [Seoul Center, Korea Basic Science Institute, Seoul 136-713 (Korea, Republic of)

    2014-11-17

    This study was designed to investigate the mechanism by which electric fields affect cell function, and to determine the optimal conditions for electric field inhibition of cancer cell proliferation. Low-intensity (<2 V/cm) and intermediate-frequency (100–300 kHz) alternating electric fields were applied to glioblastoma cell lines. These electric fields inhibited cell proliferation by inducing cell cycle arrest and abnormal mitosis due to the malformation of microtubules. These effects were significantly dependent on the intensity and frequency of applied electric fields.

  17. The Vitamin D Analogue Calcipotriol Reduces the Frequency of CD8+IL-17+ T Cells in Psoriasis Lesions

    DEFF Research Database (Denmark)

    Dyring-Andersen, B; Bonefeld, C M; Bzorek, M

    2015-01-01

    (+) T cells and innate lymphoid cells (ILC) and their production of IL-17A, IFN-γ and IL-22 in psoriasis lesions in patients with chronic plaque psoriasis. Eighteen patients with psoriasis were included, and two similar psoriasis lesions were chosen for each patient. One lesion was treated......The vitamin D analogue calcipotriol is an immunomodulatory drug widely used to treat psoriasis; however, how calcipotriol affects the immune cells in psoriasis lesions is not fully understood. The aim of this study was to investigate the effect of calcipotriol on the frequency of CD4(+) and CD8...... with calcipotriol (50 μg/g) and the other with vehicle twice a day for 14 days. The clinical effect was measured by degree of erythema, scaling and induration in each lesion (SUM score). Skin biopsies were collected for histological and immunohistochemical analyses. Skin-derived cells were isolated and analysed...

  18. 7-Piperazinethylchrysin inhibits melanoma cell proliferation by ...

    African Journals Online (AJOL)

    PEC) on melanoma cell lines. Methods: Cell viability was analyzed by trypan blue exclusion assays and the cell cycle by flow cytometry using ModFit LT software. Specifically, cells were stained with propidium iodide (0.5 mg/mL) supplemented ...

  19. Synthetic tambjamine analogues induce mitochondrial swelling and lysosomal dysfunction leading to autophagy blockade and necrotic cell death in lung cancer.

    Science.gov (United States)

    Rodilla, Ananda M; Korrodi-Gregório, Luís; Hernando, Elsa; Manuel-Manresa, Pilar; Quesada, Roberto; Pérez-Tomás, Ricardo; Soto-Cerrato, Vanessa

    2017-02-15

    Current pharmacological treatments for lung cancer show very poor clinical outcomes, therefore, the development of novel anticancer agents with innovative mechanisms of action is urgently needed. Cancer cells have a reversed pH gradient compared to normal cells, which favours cancer progression by promoting proliferation, metabolic adaptation and evasion of apoptosis. In this regard, the use of ionophores to modulate intracellular pH appears as a promising new therapeutic strategy. Indeed, there is a growing body of evidence supporting ionophores as novel antitumour drugs. Despite this, little is known about the implications of pH deregulation and homeostasis imbalance triggered by ionophores at the cellular level. In this work, we deeply analyse for the first time the anticancer effects of tambjamine analogues, a group of highly effective anion selective ionophores, at the cellular and molecular levels. First, their effects on cell viability were determined in several lung cancer cell lines and patient-derived cancer stem cells, demonstrating their potent cytotoxic effects. Then, we have characterized the induced lysosomal deacidification, as well as, the massive cytoplasmic vacuolization observed after treatment with these compounds, which is consistent with mitochondrial swelling. Finally, the activation of several proteins involved in stress response, autophagy and apoptosis was also detected, although they were not significantly responsible for the cell death induced. Altogether, these evidences suggest that tambjamine analogues provoke an imbalance in cellular ion homeostasis that triggers mitochondrial dysfunction and lysosomal deacidification leading to a potent cytotoxic effect through necrosis in lung cancer cell lines and cancer stem cells. Copyright © 2016 Elsevier Inc. All rights reserved.

  20. Synthesis of Novel Synthetic Vitamin K Analogues Prepared by Introduction of a Heteroatom and a Phenyl Group That Induce Highly Selective Neuronal Differentiation of Neuronal Progenitor Cells.

    Science.gov (United States)

    Kimura, Kimito; Hirota, Yoshihisa; Kuwahara, Shigefumi; Takeuchi, Atsuko; Tode, Chisato; Wada, Akimori; Osakabe, Naomi; Suhara, Yoshitomo

    2017-03-23

    We synthesized novel vitamin K 2 analogues that incorporated a heteroatom and an aromatic ring in the side chain and evaluated their effect on the selective differentiation of neuronal progenitor cells into neurons in vitro. The results showed that a menaquinone-2 analogue bearing a p-fluoroaniline had the most potent activity, which was more than twice as great as the control. In addition, the neuronal selectivity was more than 3 times greater than the control.

  1. Glyphosate and AMPA inhibit cancer cell growth through inhibiting intracellular glycine synthesis.

    Science.gov (United States)

    Li, Qingli; Lambrechts, Mark J; Zhang, Qiuyang; Liu, Sen; Ge, Dongxia; Yin, Rutie; Xi, Mingrong; You, Zongbing

    2013-01-01

    Glycine is a nonessential amino acid that is reversibly converted from serine intracellularly by serine hydroxymethyltransferase. Glyphosate and its degradation product, aminomethylphosphonic acid (AMPA), are analogs to glycine, thus they may inhibit serine hydroxymethyltransferase to decrease intracellular glycine synthesis. In this study, we found that glyphosate and AMPA inhibited cell growth in eight human cancer cell lines but not in two immortalized human normal prostatic epithelial cell lines. AMPA arrested C4-2B and PC-3 cancer cells in the G1/G0 phase and inhibited entry into the S phase of the cell cycle. AMPA also promoted apoptosis in C4-2B and PC-3 cancer cell lines. AMPA upregulated p53 and p21 protein levels as well as procaspase 9 protein levels in C4-2B cells, whereas it downregulated cyclin D3 protein levels. AMPA also activated caspase 3 and induced cleavage of poly (adenosine diphosphate [ADP]-ribose) polymerase. This study provides the first evidence that glyphosate and AMPA can inhibit proliferation and promote apoptosis of cancer cells but not normal cells, suggesting that they have potentials to be developed into a new anticancer therapy.

  2. Metagenomic analysis of the rumen microbial community following inhibition of methane formation by a halogenated methane analogue

    Directory of Open Access Journals (Sweden)

    Stuart E Denman

    2015-10-01

    Full Text Available Japanese goats fed a diet of 50% Timothy grass and 50% concentrate with increasing levels of the anti-methanogenic compound, bromochloromethane (BCM were investigated with respect to the microbial shifts in the rumen. Microbial ecology methods identified many species that exhibited positive and negative responses to the increasing levels of BCM. The methane-inhibited rumen appeared to adapt to the higher H2 levels by shifting fermentation to propionate which was mediated by an increase in the population of hydrogen-consuming Prevotella and Selenomonas spp. Metagenomic analysis of propionate production pathways was dominated by genomic content from these species. Reductive acetogenic marker gene libraries and metagenomics analysis indicate that reductive acetogenic species do not play a major role in the BCM treated rumen.

  3. Post-exercise abdominal, subcutaneous adipose tissue lipolysis in fasting subjects is inhibited by infusion of the somatostatin analogue octreotide

    DEFF Research Database (Denmark)

    Enevoldsen, Lotte H; Polak, Jan; Simonsen, Lene

    2007-01-01

    .c., abdominal adipose tissue metabolism, before, during and after exercise in healthy, fasting, young male subjects. The adipose tissue net releases of fatty acids and glycerol were measured by arterio-venous catheterizations and simultaneous measurements of adipose tissue blood flow with the local Xe....... The results show that octreotide infusion during rest increased lipolysis and fatty acid release from the abdominal, s.c. adipose tissue. The exercise-induced increase in lipolysis and fatty acid release does not seem to be affected by octreotide when compared with the control study without octreotide...... infusion while the post-exercise increase in lipolysis is inhibited by octreotide, suggesting that the exercise-induced increase in GH secretion plays a role for the post-exercise lipolysis in s.c., abdominal adipose tissue....

  4. Thrombopoietin inhibits murine mast cell differentiation

    Science.gov (United States)

    Martelli, Fabrizio; Ghinassi, Barbara; Lorenzini, Rodolfo; Vannucchi, Alessandro M; Rana, Rosa Alba; Nishikawa, Mitsuo; Partamian, Sandra; Migliaccio, Giovanni; Migliaccio, Anna Rita

    2009-01-01

    We have recently shown that Mpl, the thrombopoietin receptor, is expressed on murine mast cells and on their precursors and that targeted deletion of the Mpl gene increases mast cell differentiation in mice. Here we report that treatment of mice with thrombopoietin, or addition of this growth factor to bone marrow-derived mast cell cultures, severely hampers the generation of mature cells from their precursors by inducing apoptosis. Analysis of the expression profiling of mast cells obtained in the presence of thrombopoietin suggests that thrombopoietin induces apoptosis of mast cells by reducing expression of the transcription factor Mitf and its target anti-apoptotic gene Bcl2. PMID:18276801

  5. Inhibition of fatty acid metabolism reduces human myeloma cells proliferation.

    Directory of Open Access Journals (Sweden)

    José Manuel Tirado-Vélez

    Full Text Available Multiple myeloma is a haematological malignancy characterized by the clonal proliferation of plasma cells. It has been proposed that targeting cancer cell metabolism would provide a new selective anticancer therapeutic strategy. In this work, we tested the hypothesis that inhibition of β-oxidation and de novo fatty acid synthesis would reduce cell proliferation in human myeloma cells. We evaluated the effect of etomoxir and orlistat on fatty acid metabolism, glucose metabolism, cell cycle distribution, proliferation, cell death and expression of G1/S phase regulatory proteins in myeloma cells. Etomoxir and orlistat inhibited β-oxidation and de novo fatty acid synthesis respectively in myeloma cells, without altering significantly glucose metabolism. These effects were associated with reduced cell viability and cell cycle arrest in G0/G1. Specifically, etomoxir and orlistat reduced by 40-70% myeloma cells proliferation. The combination of etomoxir and orlistat resulted in an additive inhibitory effect on cell proliferation. Orlistat induced apoptosis and sensitized RPMI-8226 cells to apoptosis induction by bortezomib, whereas apoptosis was not altered by etomoxir. Finally, the inhibitory effect of both drugs on cell proliferation was associated with reduced p21 protein levels and phosphorylation levels of retinoblastoma protein. In conclusion, inhibition of fatty acid metabolism represents a potential therapeutic approach to treat human multiple myeloma.

  6. Synthesis of a Benzene-containing C1-Phosphonate Analogue of UDP-GlcNAc for the Inhibition of O-GlcNAc Transferase

    Energy Technology Data Exchange (ETDEWEB)

    Im, Jungkyun [Soonchunhyang Univ., Asan (Korea, Republic of)

    2016-01-15

    I report here the design, synthesis, and biological evaluation of a new C1-phosphonate analogue of UDP-GlcNAc as a potential inhibitor of OGT, an enzyme responsible for O-GlcNAc modification. The analogue was designed to mimic the transition state of the natural donor involved in the enzymatic reaction. However, the analogue showed somehow low activity as an inhibitor of OGT.

  7. Apoptosis of human lung adenocarcinoma A549 cells induced by prodigiosin analogue obtained from an entomopathogenic bacterium Serratia marcescens.

    Science.gov (United States)

    Zhou, Wei; Jin, Zhi-Xiong; Wan, Yong-Ji

    2010-12-01

    An entomopathogenic bacterial strain SCQ1 was isolated from silkworm (Bombyx mori) and identified as Serratia marcescens via 16S rRNA gene analysis. This strain produces a red pigment that causes acute septicemia of silkworm. The red pigment of strain SCQ1 was identified as prodigiosin analogue (PGA) with various reported biological activities. In this study, we found that low concentration of PGA showed significant anticancer activity in human lung adenocarcinoma A549 cells, but has little effect in human bone marrow stem cells, in vitro. By exposure to different concentrations of PGA for 24 h, morphological changes and the MTT assay showed that A549 cell line was very sensitive to PGA, with IC(50) value about 2.2 mg/L. Early stage of apoptosis was detected by flow cytometry while A549 cells were treated with PGA for 4 and 12 h, respectively. The proportion of dead cells was increased with treatment time or the concentrations of PGA, but it was inversely proportional to that of apoptotic cells. These results indicate that PGA obtained from strain SCQ1 induces apoptosis in A549 cells, but the molecular mechanisms of cell death are complicated, and the S. marcescens strain SCQ1 may serve as a source of the anticancer compound, PGA.

  8. Hexamethoxylated Monocarbonyl Analogues of Curcumin Cause G2/M Cell Cycle Arrest in NCI-H460 Cells via Michael Acceptor-Dependent Redox Intervention.

    Science.gov (United States)

    Li, Yan; Zhang, Li-Ping; Dai, Fang; Yan, Wen-Jing; Wang, Hai-Bo; Tu, Zhi-Shan; Zhou, Bo

    2015-09-09

    Curcumin, derived from the dietary spice turmeric, holds promise for cancer prevention. This prompts much interest in investigating the action mechanisms of curcumin and its analogues. Two symmetrical hexamethoxy-diarylpentadienones (1 and 2) as cucumin analogues were reported to possess significantly enhanced cytotoxicity compared with the parent molecule. However, the detailed mechanisms remain unclear. In this study, compounds 1 and 2 were identified as the G2/M cell cycle arrest agents to mediate the cytotoxicity toward NCI-H460 cells via Michael acceptor-dependent redox intervention. Compared with curcumin, they could more easily induce a burst of reactive oxygen species (ROS) and collapse of the redox buffering system. One possible reason is that they could more effectively target intracellular TrxR to convert this antioxidant enzyme into a ROS promoter. Additionally, they caused up-regulation of p53 and p21 and down-regulation of redox-sensitive Cdc25C along with cyclin B1/Cdk1 in a Michael acceptor- and ROS-dependent fashion. Interestingly, in comparison with compound 2, compound 1 displayed a relatively weak ability to generate ROS but increased cell cycle arrest activity and cytotoxicity probably due to its Michael acceptor-dependent microtubule-destabilizing effect and greater GST-inhibitory activity, as well as its enhanced cellular uptake. This work provides useful information for understanding Michael acceptor-dependent and redox-mediated cytotoxic mechanisms of curcumin and its active analogues.

  9. Multicomponent synthesis of 4,4-dimethyl sterol analogues and their effect on eukaryotic cells.

    Science.gov (United States)

    Alonso, Fernando; Cirigliano, Adriana M; Dávola, María Eugenia; Cabrera, Gabriela M; García Liñares, Guadalupe E; Labriola, Carlos; Barquero, Andrea A; Ramírez, Javier A

    2014-06-01

    Most sterols, such as cholesterol and ergosterol, become functional only after the removal of the two methyl groups at C-4 from their biosynthetic precursors. Nevertheless, some findings suggest that 4,4-dimethyl sterols might be involved in specific physiological processes. In this paper we present the synthesis of a collection of analogues of 4,4-dimethyl sterols with a diamide side chain and a preliminary analysis of their in vitro activity on selected biological systems. The key step for the synthesis involves an Ugi condensation, a versatile multicomponent reaction. Some of the new compounds showed antifungal and cytotoxic activity. Copyright © 2014 Elsevier Inc. All rights reserved.

  10. Nesfatin-1 inhibits ovarian epithelial carcinoma cell proliferation in vitro

    International Nuclear Information System (INIS)

    Xu, Yang; Pang, Xiaoyan; Dong, Mei; Wen, Fang; Zhang, Yi

    2013-01-01

    Highlights: •Nesfatin-1 inhibits the proliferation and growth of HO-8910 cells by G1 phase arrest. •Nesfatin-1 enhances HO-8910 cell apoptosis. •Nesfatin-1 inhibits HO-8910 cell proliferation via mTOR and RhoA/ROCK signaling pathway. •The first report of nesfatin-1-mediated proliferation in ovarian epithelial carcinoma. -- Abstract: Nesfatin-1, an 82-amino-acid peptide derived from a 396-amino-acid precursor protein nucleobindin 2 (NUCB2), was originally identified in hypothalamic nuclei involved in the regulation of food intake. It was recently reported that nesfatin-1 is a novel depot specific adipokine preferentially produced by subcutaneous tissue, with obesity- and food deprivation-regulated expression. Although a relation between ovarian cancer mortality and obesity has been previously established, a role of nesfatin-1 in ovarian epithelial carcinoma remains unknown. The aim of the present study is to examine the effect of nesfatin-1 on ovary carcinoma cells proliferation. We found that nesfatin-1 inhibits the proliferation and growth of HO-8910 cells by G1 phase arrest, this inhibition could be abolished by nesfatin-1 neutralizing antibody. Nesfatin-1 enhances HO-8910 cell apoptosis, activation of mammalian target of rapamycin (mTOR) and RhoA/ROCK signaling pathway block the effects of nesfatin-1-induced apoptosis, therefore reverses the inhibition of HO-8910 cell proliferation by nesfatin-1. In conclusion, the present study demonstrated that nesfatin-1 can inhibit the proliferation in human ovarian epithelial carcinoma cell line HO-8910 cells through inducing apoptosis via mTOR and RhoA/ROCK signaling pathway. This study provides a novel regulatory signaling pathway of nesfatin-1-regulated ovarian epithelial carcinoma growth and may contribute to ovarian cancer prevention and therapy, especially in obese patients

  11. Nesfatin-1 inhibits ovarian epithelial carcinoma cell proliferation in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Yang; Pang, Xiaoyan; Dong, Mei; Wen, Fang, E-mail: wenfang64@hotmail.com; Zhang, Yi, E-mail: syzi960@yahoo.com

    2013-11-01

    Highlights: •Nesfatin-1 inhibits the proliferation and growth of HO-8910 cells by G1 phase arrest. •Nesfatin-1 enhances HO-8910 cell apoptosis. •Nesfatin-1 inhibits HO-8910 cell proliferation via mTOR and RhoA/ROCK signaling pathway. •The first report of nesfatin-1-mediated proliferation in ovarian epithelial carcinoma. -- Abstract: Nesfatin-1, an 82-amino-acid peptide derived from a 396-amino-acid precursor protein nucleobindin 2 (NUCB2), was originally identified in hypothalamic nuclei involved in the regulation of food intake. It was recently reported that nesfatin-1 is a novel depot specific adipokine preferentially produced by subcutaneous tissue, with obesity- and food deprivation-regulated expression. Although a relation between ovarian cancer mortality and obesity has been previously established, a role of nesfatin-1 in ovarian epithelial carcinoma remains unknown. The aim of the present study is to examine the effect of nesfatin-1 on ovary carcinoma cells proliferation. We found that nesfatin-1 inhibits the proliferation and growth of HO-8910 cells by G1 phase arrest, this inhibition could be abolished by nesfatin-1 neutralizing antibody. Nesfatin-1 enhances HO-8910 cell apoptosis, activation of mammalian target of rapamycin (mTOR) and RhoA/ROCK signaling pathway block the effects of nesfatin-1-induced apoptosis, therefore reverses the inhibition of HO-8910 cell proliferation by nesfatin-1. In conclusion, the present study demonstrated that nesfatin-1 can inhibit the proliferation in human ovarian epithelial carcinoma cell line HO-8910 cells through inducing apoptosis via mTOR and RhoA/ROCK signaling pathway. This study provides a novel regulatory signaling pathway of nesfatin-1-regulated ovarian epithelial carcinoma growth and may contribute to ovarian cancer prevention and therapy, especially in obese patients.

  12. Inhibition of GRP78 abrogates radioresistance in oropharyngeal carcinoma cells after EGFR inhibition by cetuximab.

    Directory of Open Access Journals (Sweden)

    Chaonan Sun

    Full Text Available The EGFR-specific mAb cetuximab is one of the most effective treatments for oropharyngeal carcinoma, while patient responses to EGFR inhibitors given alone are modest. Combination treatment with radiation can improve the efficacy of treatment through increasing radiosensitivity, while resistance to radiation after administration of cetuximab limits its efficiency. Radiation and drugs can damage the endoplasmic reticulum (ER homeostatic state and result in ER stress (ERS, subsequently causing resistance to radiation and drugs. Whether the ERS pathway is involved in radioresistance after administration of cetuximab has not been reported. Herein, we show that cetuximab could increase the radiosensitivity of FaDu cells but not Detroit562 cells. In addition, cetuximab inhibited the radiation-induced activation of the ERS signalling pathway IRE1α/ATF6-GRP78 in FaDu cells, while this effect was absent in Detroit562 cells. Silencing GRP78 increased the radiosensitivity of oropharyngeal carcinoma cells and inhibited radiation-induced DNA double-strand-break (DSB repair and autophagy. More interestingly, silencing GRP78 abrogated resistance to cetuximab and radiation in Detroit562 cells and had a synergistic effect with cetuximab in increasing the radiosensitivity of FaDu cells. Immunohistochemistry showed that overexpression of both GRP78 and EGFR was associated with a poor prognosis in oropharyngeal carcinoma patients (P<0.05. Overall, the results of this study show that radioresistance after EGFR inhibition by cetuximab is mediated by the ERS signalling pathway IRE1α/ATF6-GRP78. This suppression was consequently unable to inhibit radiation-induced DSB repair and autophagy in oropharyngeal carcinoma cells, which conferred resistance to radiotherapy and cetuximab. These results suggest that the cooperative effects of radiotherapy and cetuximab could be further improved by inhibiting GRP78 in non-responsive oropharyngeal carcinoma patients.

  13. Cyperus scariosus Chloroform Fraction Inhibits T cell Responses in ...

    African Journals Online (AJOL)

    Erah

    CSC did not significantly (p < 0.01) suppress Th2 (IL-4) system. Conclusion: The findings from this investigation reveal that C. scariosus causes immunosuppression by inhibiting Th1 cytokines. Keywords: Cyperus scariosus; Immunosuppression; Humoral antibody titre; Cell-mediated immune response; CD 4+ T- helper cells ...

  14. MicroRNA-144 inhibits hepatocellular carcinoma cell proliferation

    Indian Academy of Sciences (India)

    MiR-144 was shown to besignificantly down-regulated in HCC tissues and cell lines. Subsequently, overexpression of miR-144 was transfectedinto HCC cell lines so as to investigate its biological function, including MTT, colony formation, and transwell assays.Gain of function assay revealed miR-144 remarkably inhibited ...

  15. Synthesis and biochemical evaluation of benzoylbenzophenone thiosemicarbazone analogues as potent and selective inhibitors of cathepsin L

    DEFF Research Database (Denmark)

    Parker, Erica N; Song, Jiangli; Kishore Kumar, G D

    2015-01-01

    selective in their inhibition of cathepsin L compared to cathepsin B. Thiosemicarbazone analogue 32 inhibited invasion through Matrigel of MDA-MB-231 breast cancer cells by 70% at 10μM. Thiosemicarbazone analogue 8 significantly inhibited the invasive potential of PC-3ML prostate cancer cells by 92% at 5μ......Upregulation of cathepsin L in a variety of tumors and its ability to promote cancer cell invasion and migration through degradation of the extracellular matrix suggest that cathepsin L is a promising biological target for the development of anti-metastatic agents. Based on encouraging results from......) was well-tolerated in a CDF1 mouse model bearing an implanted C3H mammary carcinoma, and showed efficacy in tumor growth delay. Low cytotoxicity, inhibition of cell invasion, and in vivo tolerability are desirable characteristics for anti-metastatic agents functioning through an inhibition of cathepsin L...

  16. Glyphosate and AMPA inhibit cancer cell growth through inhibiting intracellular glycine synthesis

    Directory of Open Access Journals (Sweden)

    Li Q

    2013-07-01

    Full Text Available Qingli Li,1,2 Mark J Lambrechts,1 Qiuyang Zhang,1 Sen Liu,1 Dongxia Ge,1 Rutie Yin,2 Mingrong Xi,2 Zongbing You1 1Departments of Structural and Cellular Biology and Orthopaedic Surgery, Tulane Cancer Center and Louisiana Cancer Research Consortium, Tulane Center for Stem Cell Research and Regenerative Medicine, and Tulane Center for Aging, Tulane University Health Sciences Center, New Orleans, LA, USA; 2Department of Obstetrics and Gynecology, West China Second University Hospital, Sichuan University, Chengdu, People’s Republic of China Abstract: Glycine is a nonessential amino acid that is reversibly converted from serine intracellularly by serine hydroxymethyltransferase. Glyphosate and its degradation product, aminomethylphosphonic acid (AMPA, are analogs to glycine, thus they may inhibit serine hydroxymethyltransferase to decrease intracellular glycine synthesis. In this study, we found that glyphosate and AMPA inhibited cell growth in eight human cancer cell lines but not in two immortalized human normal prostatic epithelial cell lines. AMPA arrested C4-2B and PC-3 cancer cells in the G1/G0 phase and inhibited entry into the S phase of the cell cycle. AMPA also promoted apoptosis in C4-2B and PC-3 cancer cell lines. AMPA upregulated p53 and p21 protein levels as well as procaspase 9 protein levels in C4-2B cells, whereas it downregulated cyclin D3 protein levels. AMPA also activated caspase 3 and induced cleavage of poly (adenosine diphosphate [ADP]-ribose polymerase. This study provides the first evidence that glyphosate and AMPA can inhibit proliferation and promote apoptosis of cancer cells but not normal cells, suggesting that they have potentials to be developed into a new anticancer therapy. Keywords: serine hydroxymethyltransferase, prostate cancer, apoptosis

  17. Potential of Resveratrol Analogues as Antagonists of Osteoclasts and Promoters of Osteoblasts

    DEFF Research Database (Denmark)

    Kupisiewicz, Katarzyna; Boissy, Patrice; Abdallah, Basem M

    2010-01-01

    The plant phytoalexin resveratrol was previously demonstrated to inhibit the differentiation and bone resorbing activity of osteoclasts, to promote the formation of osteoblasts from mesenchymal precursors in cultures, and inhibit myeloma cell proliferation, when used at high concentrations....... In the current study, we screened five structurally modified resveratrol analogues for their ability to modify the differentiation of osteoclasts and osteoblasts and proliferation of myeloma cells. Compared to resveratrol, analogues showed an up to 5,000-fold increased potency to inhibit osteoclast...... differentiation. To a lesser extent, resveratrol analogues also promoted osteoblast maturation. However, they did not antagonize the proliferation of myeloma cells. The potency of the best-performing candidate in vitro was tested in vivo in an ovariectomy-induced model of osteoporosis, but an effect on bone loss...

  18. Protein thiophosphorylation associated with secretory inhibition in permeabilized chromaffin cells

    International Nuclear Information System (INIS)

    Brooks, J.C.; Brooks, M.

    1985-01-01

    Permeabilized cells treated with the adenosine triphosphate analog, ( 35 S)adenosine-5'-0-3(3-thiotriphosphate) ((γ- 35 S)ATP), showed thiophosphorylation of a small number of cellular proteins. A 54 kilodalton (kDa) protein was heavily thiophosphorylated in unstimulated control cells and a 43 kilodalton protein was more heavily thiophosphorylated in calcium stimulated cells. Intact cells incorporated 35 S into a series of higher molecular weight proteins. Stimulation of prelabelled, permeabilized cells resulted in a loss of 35 S from the cells over a 20 min period. Treatment of permeabilized cells with ATPγS inhibited secretion and 35 S incorporation into the cells. Pretreatment with ATPγS resulted in subsequent inhibition of both secretion and the ability of the cells to incorporate 35 S from (γ- 35 S)ATP. These results indicate that the sites normally available for phosphorylation were inactivated by thiophosphorylation and were unavailable to participate in the secretory process. The inhibition of secretion associated with thiophosphorylation of these proteins suggests that they may play a role in the control of secretion by chromaffin cells. 15 references, 1 figure, 3 tables

  19. Thrombomodulin inhibits the activation of eosinophils and mast cells.

    Science.gov (United States)

    Roeen, Ziaurahman; Toda, Masaaki; D'Alessandro-Gabazza, Corina N; Onishi, Masahiro; Kobayashi, Tetsu; Yasuma, Taro; Urawa, Masahito; Taguchi, Osamu; Gabazza, Esteban C

    2015-01-01

    Eosinophils and mast cells play critical roles in the pathogenesis of bronchial asthma. Activation of both cells leads to the release of pro-inflammatory mediators in the airway of asthmatic patients. Recently, we have shown that inhaled thrombomodulin inhibits allergic bronchial asthma in a mouse model. In the present study, we hypothesize that thrombomodulin can inhibit the activation of eosinophils and mast cells. The effect of thrombomodulin on the activation and release of inflammatory mediators from eosinophils and mast cells was evaluated. Thrombomodulin inhibited the eotaxin-induced chemotaxis, upregulation of CD11b and degranulation of eosinophils. Treatment with thrombomodulin also significantly suppressed the degranulation and synthesis of inflammatory cytokines and chemokines in eosinophils and mast cells. Mice treated with a low-dose of inhaled thrombomodulin have decreased number of eosinophils and activated mast cells and Th2 cytokines in the lungs compared to untreated mice. The results of this study suggest that thrombomodulin may modulate allergic responses by inhibiting the activation of both eosinophils and mast cells. Copyright © 2014 Elsevier Inc. All rights reserved.

  20. Investigating β-N-Methylamino-l-alanine Misincorporation in Human Cell Cultures: A Comparative Study with Known Amino Acid Analogues

    Directory of Open Access Journals (Sweden)

    Rianita van Onselen

    2017-12-01

    Full Text Available Misincorporation of β-N-methylamino-l-alanine (BMAA into proteins has been proposed to be a mechanism of toxicity to explain the role of BMAA in neurodegenerative disease development. However, studies have shown that all detectable BMAA can be removed from proteins by SDS-PAGE purification and that the toxicity of l-canavanine cannot be reproduced in prokaryotes or in a rat pheochromocytoma cell line, strongly indicating that the misincorporation hypothesis of BMAA should be re-investigated. The aim of this study was therefore to determine if BMAA misincorporates into proteins in cells of human origin with subsequent misincorporation-type toxicity. Almost complete loss of viability in response to exposure to l-4-fluorophenylalanine and l-m-tyrosine was observed in all of the cell lines, corresponding to a concentration-dependent increase of the analogues in protein extracts from exposed cells. In contrast, BMAA exposure resulted in slight toxicity in one of the cell lines but the observed toxicity was not the result of misincorporation of BMAA into proteins, as no BMAA was detected in any of the SDS-PAGE purified protein extracts that were obtained from the cells following BMAA exposure. The results show that BMAA is not misincorporated into human proteins and that misincorporation is not a valid mechanism of toxicity.

  1. BALANOL ANALOGUES

    DEFF Research Database (Denmark)

    1997-01-01

    The present invention relates to a solid phase methodology for the preparation of a combinatorial library of structural analogues of the natural product balanol (ophiocordin, azepinostatin), which is a protein kinase C (PKC) and protein kinase A (PKA) inhibitor. The method comprises solid...

  2. Quercetin inhibits adipogenesis of muscle progenitor cells in vitro

    Directory of Open Access Journals (Sweden)

    Tomoko Funakoshi

    2018-03-01

    Full Text Available Muscle satellite cells are committed myogenic progenitors capable of contributing to myogenesis to maintain adult muscle mass and function. Several experiments have demonstrated that muscle satellite cells can differentiate into adipocytes in vitro, supporting the mesenchymal differentiation potential of these cells. Moreover, muscle satellite cells may be a source of ectopic muscle adipocytes, explaining the lipid accumulation often observed in aged skeletal muscle (sarcopenia and in muscles of patients` with diabetes. Quercetin, a polyphenol, is one of the most abundant flavonoids distributed in edible plants, such as onions and apples, and possesses antioxidant, anticancer, and anti-inflammatory properties. In this study, we examined whether quercetin inhibited the adipogenesis of muscle satellite cells in vitro with primary cells from rat limbs by culture in the presence of quercetin under adipogenic conditions. Morphological observations, Oil Red-O staining results, triglyceride content analysis, and quantitative reverse transcription polymerase chain reaction revealed that quercetin was capable of inhibiting the adipogenic induction of muscle satellite cells into adipocytes in a dose-dependent manner by suppressing the transcript levels of adipogenic markers, such as peroxisome proliferator-activated receptor-γ and fatty acid binding protein 4. Our results suggested that quercetin inhibited the adipogenesis of muscle satellite cells in vitro by suppressing the transcription of adipogenic markers. Keywords: Quercetin, Muscle satellite cell, Differentiation, Intramuscular lipid

  3. Medical Therapies for Endometriosis Differentially Inhibit Stem Cell Recruitment.

    Science.gov (United States)

    Ersoy, Gulcin Sahin; Zolbin, Masoumeh Majidi; Cosar, Emine; Mamillapalli, Ramanaiah; Taylor, Hugh S

    2017-06-01

    To determine the effect of the 3 well-known endometriosis treatments on stem cell recruitment to endometriotic lesions. C57BL/6 mice (aged 8 weeks, n = 20) underwent bone marrow transplant following submyeloablation with 5-fluorouracil using 20 × 10 6 bone marrow stem cells from green fluorescent protein (GFP) mice. Two weeks after transplantation, experimental endometriosis was created in mice by suturing segments of the uterine horn into the peritoneal cavity. Mice were then randomized to receive treatment with medroxyprogesterone acetate (MPA), leuprolide acetate (Gonadotrophin-Releasing Hormone Analogue [GnRHa]), letrozole, or vehicle control (dimethyl sulfoxide). After 3 weeks of treatment, the mice were killed and the endometriosis lesions evaluated. All 3 treatments resulted in a significant reduction in lesion volume and weight. Estrogen deprivation using GnRHa or letrozole resulted in greater lesion regression than the progestin MPA. The GFP + /CD45 - bone marrow-derived stem cells (BMDSCs) engrafted the lesions of endometriosis. Estrogen deprivation using GnRHa or letrozole significantly reduced BMDSC engraftment in the endometriosis lesions. MPA failed to significantly reduce stem cell number in endometriosis. The superiority of estrogen deprivation over progestin therapy in depriving the lesions of stem cells may have implications for the long-term treatment of endometriosis. Reduced stem cell engraftment is likely to result in long-term regression of the lesions, whereas progestins may only prevent their growth acutely.

  4. Lutein Inhibits the Migration of Retinal Pigment Epithelial Cells via Cytosolic and Mitochondrial Akt Pathways (Lutein Inhibits RPE Cells Migration

    Directory of Open Access Journals (Sweden)

    Ching-Chieh Su

    2014-08-01

    Full Text Available During the course of proliferative vitreoretinopathy (PVR, the retinal pigment epithelium (RPE cells will de-differentiate, proliferate, and migrate onto the surfaces of the sensory retina. Several studies have shown that platelet-derived growth factor (PDGF can induce migration of RPE cells via an Akt-related pathway. In this study, the effect of lutein on PDGF-BB-induced RPE cells migration was examined using transwell migration assays and Western blot analyses. We found that both phosphorylation of Akt and mitochondrial translocation of Akt in RPE cells induced by PDGF-BB stimulation were suppressed by lutein. Furthermore, the increased migration observed in RPE cells with overexpressed mitochondrial Akt could also be suppressed by lutein. Our results demonstrate that lutein can inhibit PDGF-BB induced RPE cells migration through the inhibition of both cytoplasmic and mitochondrial Akt activation.

  5. Magnolol Inhibits the Growth of Non-Small Cell Lung Cancer via Inhibiting Microtubule Polymerization

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    Jia Shen

    2017-07-01

    Full Text Available Background: The tubulin/microtubule system, which is an integral component of the cytoskeleton, plays an essential role in mitosis. Targeting mitotic progression by disturbing microtubule dynamics is a rational strategy for cancer treatment. Methods: Microtubule polymerization assay was performed to examine the effect of Magnolol (a novel natural phenolic compound isolated from Magnolia obovata on cellular microtubule polymerization in human non-small cell lung cancer (NSCLC cells. Cell cycle analysis, mitotic index assay, cell proliferation assay, colony formation assay, western blotting analysis of cell cycle regulators, Annexin V-FITC/PI staining, and live/dead viability staining were carried out to investigate the Magnolol’s inhibitory effect on proliferation and viability of NSCLS cells in vitro. Xenograft model of human A549 NSCLC tumor was used to determine the Magnolol’s efficacy in vivo. Results: Magnolol treatment effectively inhibited cell proliferation and colony formation of NSCLC cells. Further study proved that Magnolol induced the mitotic phase arrest and inhibited G2/M progression in a dose-dependent manner, which were mechanistically associated with expression alteration of a series of cell cycle regulators. Furthermore, Magnolol treatment disrupted the cellular microtubule organization via inhibiting the polymerization of microtubule. We also found treatment with NSCLC cells with Magnolol resulted in apoptosis activation through a p53-independent pathway, and autophgy induction via down-regulation of the Akt/mTOR pathway. Finally, Magnolol treatment significantly suppressed the NSCLC tumor growth in mouse xenograft model in vivo. Conclusion: These findings identify Magnolol as a promising candidate with anti-microtubule polymerization activity for NSCLC treatment.

  6. Thiacetazone, an antitubercular drug that inhibits cyclopropanation of cell wall mycolic acids in mycobacteria.

    Directory of Open Access Journals (Sweden)

    Anuradha Alahari

    2007-12-01

    Full Text Available Mycolic acids are a complex mixture of branched, long-chain fatty acids, representing key components of the highly hydrophobic mycobacterial cell wall. Pathogenic mycobacteria carry mycolic acid sub-types that contain cyclopropane rings. Double bonds at specific sites on mycolic acid precursors are modified by the action of cyclopropane mycolic acid synthases (CMASs. The latter belong to a family of S-adenosyl-methionine-dependent methyl transferases, of which several have been well studied in Mycobacterium tuberculosis, namely, MmaA1 through A4, PcaA and CmaA2. Cyclopropanated mycolic acids are key factors participating in cell envelope permeability, host immunomodulation and persistence of M. tuberculosis. While several antitubercular agents inhibit mycolic acid synthesis, to date, the CMASs have not been shown to be drug targets.We have employed various complementary approaches to show that the antitubercular drug, thiacetazone (TAC, and its chemical analogues, inhibit mycolic acid cyclopropanation. Dramatic changes in the content and ratio of mycolic acids in the vaccine strain Mycobacterium bovis BCG, as well as in the related pathogenic species Mycobacterium marinum were observed after treatment with the drugs. Combination of thin layer chromatography, mass spectrometry and Nuclear Magnetic Resonance (NMR analyses of mycolic acids purified from drug-treated mycobacteria showed a significant loss of cyclopropanation in both the alpha- and oxygenated mycolate sub-types. Additionally, High-Resolution Magic Angle Spinning (HR-MAS NMR analyses on whole cells was used to detect cell wall-associated mycolates and to quantify the cyclopropanation status of the cell envelope. Further, overexpression of cmaA2, mmaA2 or pcaA in mycobacteria partially reversed the effects of TAC and its analogue on mycolic acid cyclopropanation, suggesting that the drugs act directly on CMASs.This is a first report on the mechanism of action of TAC, demonstrating the

  7. Human mesenchymal stem cells inhibit osteoclastogenesis through osteoprotegerin production.

    Science.gov (United States)

    Oshita, Koichi; Yamaoka, Kunihiro; Udagawa, Nobuyuki; Fukuyo, Shunsuke; Sonomoto, Koshiro; Maeshima, Keisuke; Kurihara, Ryuji; Nakano, Kazuhisa; Saito, Kazuyoshi; Okada, Yosuke; Chiba, Kenji; Tanaka, Yoshiya

    2011-06-01

    Mesenchymal stem cells (MSCs) have been proposed to be a useful tool for treatment of rheumatoid arthritis (RA), not only because of their multipotency but also because of their immunosuppressive effect on lymphocytes, dendritic cells, and other proinflammatory cells. Since bone destruction caused by activated osteoclasts occurs in RA, we undertook the present study to investigate the effect of MSCs on osteoclast function and differentiation in order to evaluate their potential use in RA therapy. Human MSCs and peripheral blood mononuclear cells were cultured under cell-cell contact-free conditions with osteoclast induction medium. Differentiation into osteoclast-like cells was determined by tartrate-resistant acid phosphatase staining and expression of osteoclast differentiation markers. The number of osteoclast-like cells was decreased and expression of cathepsin K and nuclear factor of activated T cells c1 (NF-ATc1) was down-regulated by the addition of either MSCs or a conditioned medium obtained from MSCs. Osteoprotegerin (OPG) was constitutively produced by MSCs and inhibited osteoclastogenesis. However, osteoclast differentiation was not fully recovered upon treatment with either anti-OPG antibody or OPG small interfering RNA, suggesting that OPG had only a partial role in the inhibitory effect of MSCs. Moreover, bone-resorbing activity of osteoclast-like cells was partially recovered by addition of anti-OPG antibody into the conditioned medium. The present results indicate that human MSCs constitutively produce OPG, resulting in inhibition of osteoclastogenesis and expression of NF-ATc1 and cathepsin K in the absence of cell-cell contact. Therefore, we conclude that human MSCs exert a suppressive effect on osteoclastogenesis, which may be beneficial in inhibition of joint damage in RA. Copyright © 2011 by the American College of Rheumatology.

  8. Cell-cycle inhibition by Helicobacter pylori L-asparaginase.

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    Claudia Scotti

    Full Text Available Helicobacter pylori (H. pylori is a major human pathogen causing chronic gastritis, peptic ulcer, gastric cancer, and mucosa-associated lymphoid tissue lymphoma. One of the mechanisms whereby it induces damage depends on its interference with proliferation of host tissues. We here describe the discovery of a novel bacterial factor able to inhibit the cell-cycle of exposed cells, both of gastric and non-gastric origin. An integrated approach was adopted to isolate and characterise the molecule from the bacterial culture filtrate produced in a protein-free medium: size-exclusion chromatography, non-reducing gel electrophoresis, mass spectrometry, mutant analysis, recombinant protein expression and enzymatic assays. L-asparaginase was identified as the factor responsible for cell-cycle inhibition of fibroblasts and gastric cell lines. Its effect on cell-cycle was confirmed by inhibitors, a knockout strain and the action of recombinant L-asparaginase on cell lines. Interference with cell-cycle in vitro depended on cell genotype and was related to the expression levels of the concurrent enzyme asparagine synthetase. Bacterial subcellular distribution of L-asparaginase was also analysed along with its immunogenicity. H. pylori L-asparaginase is a novel antigen that functions as a cell-cycle inhibitor of fibroblasts and gastric cell lines. We give evidence supporting a role in the pathogenesis of H. pylori-related diseases and discuss its potential diagnostic application.

  9. The inhibition of repair in UV irradiated human cells

    International Nuclear Information System (INIS)

    Collins, A.R.S.; Schor, S.L.; Johnson, R.T.

    1977-01-01

    Three different assay procedures are used to determine the effects of hydroxyurea on excision repair in UV-irradiated HeLa cells. At the cytological level, incubation of UV-irradiated metaphase cells with hydroxyurea caused chromosome decondensation. Using a modified alkaline sucrose gradient sedimentation technique involving minimal lysis before centrifugation, a marked retardation was found in the sedimentation of DNA from UV-irradiated cells incubated for a short period with hydroxyurea. The effect of hydroxyurea on the incorporation of [ 3 H]thymidine by UV-irradiated G1 cells was found to depend on the concentration of thymidine present in the medium. The results point to an inhibition of repair DNA synthesis by hydroxyurea (or deoxyadenosine), at the level of the supply of DNA precursors, i.e. in the same way that these agents inhibit semiconservative DNA synthesis. In the presence of these inhibitors, single-strand gaps accumulate in the DNA

  10. Azidothymidine Sensitizes Primary Effusion Lymphoma Cells to Kaposi Sarcoma-Associated Herpesvirus-Specific CD4+ T Cell Control and Inhibits vIRF3 Function.

    Directory of Open Access Journals (Sweden)

    Samantha J Williamson

    2016-11-01

    Full Text Available Kaposi sarcoma-associated herpesvirus (KSHV is linked with the development of Kaposi sarcoma and the B lymphocyte disorders primary effusion lymphoma (PEL and multi-centric Castleman disease. T cell immunity limits KSHV infection and disease, however the virus employs multiple mechanisms to inhibit efficient control by these effectors. Thus KSHV-specific CD4+ T cells poorly recognize most PEL cells and even where they can, they are unable to kill them. To make KSHV-infected cells more sensitive to T cell control we treated PEL cells with the thymidine analogue azidothymidine (AZT, which sensitizes PEL lines to Fas-ligand and TRAIL challenge; effector mechanisms which T cells use. PELs co-cultured with KSHV-specific CD4+ T cells in the absence of AZT showed no control of PEL outgrowth. However in the presence of AZT PEL outgrowth was controlled in an MHC-restricted manner. To investigate how AZT sensitizes PELs to immune control we first examined BJAB cells transduced with individual KSHV-latent genes for their ability to resist apoptosis mediated by stimuli delivered through Fas and TRAIL receptors. This showed that in addition to the previously described vFLIP protein, expression of vIRF3 also inhibited apoptosis delivered by these stimuli. Importantly vIRF3 mediated protection from these apoptotic stimuli was inhibited in the presence of AZT as was a second vIRF3 associated phenotype, the downregulation of surface MHC class II. Although both vFLIP and vIRF3 are expressed in PELs, we propose that inhibiting vIRF3 function with AZT may be sufficient to restore T cell control of these tumor cells.

  11. Inhibition of glutathione synthesis eliminates the adaptive response of ascitic hepatoma 22 cells to nedaplatin that targets thioredoxin reductase

    International Nuclear Information System (INIS)

    Wang, Yijun; Lu, Hongjuan; Wang, Dongxu; Li, Shengrong; Sun, Kang; Wan, Xiaochun; Taylor, Ethan Will; Zhang, Jinsong

    2012-01-01

    Thioredoxin reductase (TrxR) is a target for cancer therapy and the anticancer mechanism of cisplatin involves TrxR inhibition. We hypothesize that the anticancer drug nedaplatin (NDP), an analogue of cisplatin and a second-generation platinum complex, also targets TrxR. Furthermore, we investigate whether the therapeutic efficacy of NDP can be enhanced by simultaneous modulation of 1) TrxR, via NDP, and 2) glutathione (GSH), via the GSH synthesis inhibitor buthionine sulfoximine (BSO). Mice bearing ascitic hepatoma 22 (H22) cells were treated with NDP alone or NDP plus BSO. TrxR activity of H22 cells was inhibited by NDP in a dose-dependent manner. A high correlation between the inhibition of TrxR activity at 6 h and the inhibition of ascitic fluid volume at 72 h was established (r = 0.978, p < 0.01). As an adaptive response, the viable ascitic cancer cells after NDP treatment displayed an enlarged cell phenotype, assembled with several-fold more antioxidant enzymes and GSH-predominant non-protein free thiols. This adaptive response was largely eliminated when BSO was co-administered with NDP, leading to the decimation of the H22 cell population without enhancing renal toxicity, since at this dose, NDP did not inhibit renal TrxR activity. In conclusion, the pharmacological effect of NDP involves TrxR inhibition, and the adaptive response of NDP-treated ascitic H22 cells can be efficiently counteracted by BSO. Simultaneous modulation of TrxR and GSH on ascitic H22 cells using NDP plus BSO greatly enhances therapeutic efficacy as compared with the single modulation of TrxR using NDP alone. -- Highlights: ► Nedaplatin at a pharmacological dose inhibits TrxR in cancer cells but not in kidney. ► The nedaplatin-treated cancer cells exhibit adaptive response. ► Buthionine sulfoximine inhibits glutathione in both cancer cells and kidney. ► Buthionine sulfoximine counteracts the adaptive response to the nedaplatin treatment. ► Buthionine sulfoximine does not

  12. Inhibition of glutathione synthesis eliminates the adaptive response of ascitic hepatoma 22 cells to nedaplatin that targets thioredoxin reductase

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yijun [School of Tea and Food Science, Anhui Agricultural University, Hefei 230036, Anhui (China); Lu, Hongjuan [Productivity Center of Jiangsu Province, Nanjing 210042, Jiangsu (China); Wang, Dongxu; Li, Shengrong; Sun, Kang; Wan, Xiaochun [School of Tea and Food Science, Anhui Agricultural University, Hefei 230036, Anhui (China); Taylor, Ethan Will [Department of Nanoscience, Joint School of Nanoscience and Nanoengineering, University of North Carolina at Greensboro, Greensboro, NC 27402 (United States); Zhang, Jinsong, E-mail: zjs@ahau.edu.cn [School of Tea and Food Science, Anhui Agricultural University, Hefei 230036, Anhui (China)

    2012-12-15

    Thioredoxin reductase (TrxR) is a target for cancer therapy and the anticancer mechanism of cisplatin involves TrxR inhibition. We hypothesize that the anticancer drug nedaplatin (NDP), an analogue of cisplatin and a second-generation platinum complex, also targets TrxR. Furthermore, we investigate whether the therapeutic efficacy of NDP can be enhanced by simultaneous modulation of 1) TrxR, via NDP, and 2) glutathione (GSH), via the GSH synthesis inhibitor buthionine sulfoximine (BSO). Mice bearing ascitic hepatoma 22 (H22) cells were treated with NDP alone or NDP plus BSO. TrxR activity of H22 cells was inhibited by NDP in a dose-dependent manner. A high correlation between the inhibition of TrxR activity at 6 h and the inhibition of ascitic fluid volume at 72 h was established (r = 0.978, p < 0.01). As an adaptive response, the viable ascitic cancer cells after NDP treatment displayed an enlarged cell phenotype, assembled with several-fold more antioxidant enzymes and GSH-predominant non-protein free thiols. This adaptive response was largely eliminated when BSO was co-administered with NDP, leading to the decimation of the H22 cell population without enhancing renal toxicity, since at this dose, NDP did not inhibit renal TrxR activity. In conclusion, the pharmacological effect of NDP involves TrxR inhibition, and the adaptive response of NDP-treated ascitic H22 cells can be efficiently counteracted by BSO. Simultaneous modulation of TrxR and GSH on ascitic H22 cells using NDP plus BSO greatly enhances therapeutic efficacy as compared with the single modulation of TrxR using NDP alone. -- Highlights: ► Nedaplatin at a pharmacological dose inhibits TrxR in cancer cells but not in kidney. ► The nedaplatin-treated cancer cells exhibit adaptive response. ► Buthionine sulfoximine inhibits glutathione in both cancer cells and kidney. ► Buthionine sulfoximine counteracts the adaptive response to the nedaplatin treatment. ► Buthionine sulfoximine does not

  13. Fluoxetine regulates cell growth inhibition of interferon-α.

    Science.gov (United States)

    Lin, Yu-Min; Yu, Bu-Chin; Chiu, Wen-Tai; Sun, Hung-Yu; Chien, Yu-Chieh; Su, Hui-Chen; Yen, Shu-Yang; Lai, Hsin-Wen; Bai, Chyi-Huey; Young, Kung-Chia; Tsao, Chiung-Wen

    2016-10-01

    Fluoxetine, a well-known anti-depression agent, may act as a chemosensitizer to assist and promote cancer therapy. However, how fluoxetine regulates cellular signaling to enhance cellular responses against tumor cell growth remains unclear. In the present study, addition of fluoxetine promoted growth inhibition of interferon-alpha (IFN-α) in human bladder carcinoma cells but not in normal uroepithelial cells through lessening the IFN-α-induced apoptosis but switching to cause G1 arrest, and maintaining the IFN-α-mediated reduction in G2/M phase. Activations and signal transducer and transactivator (STAT)-1 and peroxisome proliferator-activated receptor alpha (PPAR-α) were involved in this process. Chemical inhibitions of STAT-1 or PPAR-α partially rescued bladder carcinoma cells from IFN-α-mediated growth inhibition via blockades of G1 arrest, cyclin D1 reduction, p53 downregulation and p27 upregulation in the presence of fluoxetine. However, the functions of both proteins were not involved in the control of fluoxetine over apoptosis and maintained the declined G2/M phase of IFN-α. These results indicated that activation of PPAR-α and STAT-1 participated, at least in part, in growth inhibition of IFN-α in the presence of fluoxetine.

  14. ATF3 inhibits PPARγ-stimulated transactivation in adipocyte cells

    Energy Technology Data Exchange (ETDEWEB)

    Jang, Min-Kyung; Jung, Myeong Ho, E-mail: jung0603@pusan.ac.kr

    2015-01-02

    Highlights: • ATF3 inhibits PPARγ-stimulated transcriptional activation. • ATF3 interacts with PPARγ. • ATF3 suppresses p300-mediated transcriptional coactivation. • ATF3 decreases the binding of PPARγ and recruitment of p300 to PPRE. - Abstract: Previously, we reported that activating transcription factor 3 (ATF3) downregulates peroxisome proliferator activated receptor (PPARγ) gene expression and inhibits adipocyte differentiation in 3T3-L1 cells. Here, we investigated another role of ATF3 on the regulation of PPARγ activity. ATF3 inhibited PPARγ-stimulated transactivation of PPARγ responsive element (PPRE)-containing reporter or GAL4/PPARγ chimeric reporter. Thus, ATF3 effectively repressed rosiglitazone-stimulated expression of adipocyte fatty acid binding protein (aP2), PPARγ target gene, in 3T3-L1 cells. Coimmunoprecipitation and GST pulldown assay demonstrated that ATF3 interacted with PPARγ. Accordingly, ATF3 prevented PPARγ from binding to PPRE on the aP2 promoter. Furthermore, ATF3 suppressed p300-mediated transcriptional coactivation of PPRE-containing reporter. Chromatin immunoprecipitation assay showed that overexpression of ATF3 blocked both binding of PPARγ and recruitment of p300 to PPRE on aP2 promoter induced by rosiglitazone treatment in 3T3-L1 cells. Taken together, these results suggest that ATF3 interacts with PPARγ and represses PPARγ-mediated transactivation through suppression of p300-stimulated coactivation in 3T3-L1 cells, which may play a role in inhibition of adipocyte differentiation.

  15. Antisense inhibition of hyaluronan synthase-2 in human osteosarcoma cells inhibits hyaluronan retention and tumorigenicity

    International Nuclear Information System (INIS)

    Nishida, Yoshihiro; Knudson, Warren; Knudson, Cheryl B.; Ishiguro, Naoki

    2005-01-01

    Osteosarcoma is a common malignant bone tumor associated with childhood and adolescence. The results of numerous studies have suggested that hyaluronan plays an important role in regulating the aggressive behavior of various types of cancer cells. However, no studies have addressed hyaluronan with respect to osteosarcomas. In this investigation, the mRNA expression copy number of three mammalian hyaluronan synthases (HAS) was determined using competitive RT-PCR in the osteoblastic osteosarcoma cell line, MG-63. MG-63 are highly malignant osteosarcoma cells with an abundant hyaluronan-rich matrix. The results demonstrated that HAS-2 is the predominant HAS in MG-63. Accumulation of intracellular hyaluronan increased in association with the proliferative phase of these cells. The selective inhibition of HAS-2 mRNA in MG-63 cells by antisense phosphorothioate oligonucleotides resulted in reduced hyaluronan accumulation by these cells. As expected, the reduction in hyaluronan disrupted the assembly of cell-associated matrices. However, of most interest, coincident with the reduction in hyaluronan, there was a substantial decrease in cell proliferation, a decrease in cell motility and a decrease in cell invasiveness. These data suggest that hyaluronan synthesized by HAS-2 in MG-63 plays a crucial role in osteosarcoma cell proliferation, motility, and invasion

  16. Synthesis of dansyl-labeled probe of thiophene analogue of annonaceous acetogenins for visualization of cell distribution and growth inhibitory activity toward human cancer cell lines.

    Science.gov (United States)

    Kojima, Naoto; Suga, Yuki; Matsumoto, Takuya; Tanaka, Tetsuaki; Akatsuka, Akinobu; Yamori, Takao; Dan, Shingo; Iwasaki, Hiroki; Yamashita, Masayuki

    2015-03-15

    The convergent synthesis of the dansyl-labeled probe of the thiophene-3-carboxamide analogue of annonaceous acetogenins, which shows potent antitumor activity, was accomplished by two asymmetric alkynylations of the 2,5-diformyl THF equivalent with an alkyne having a thiophene moiety and another alkyne tagged with a dansyl group. The growth inhibitory profiles toward 39 human cancer cell lines revealed that the probe retained the biological function of its mother compound, and would be useful for studying cellular activity. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. Metformin inhibits cell cycle progression of B-cell chronic lymphocytic leukemia cells.

    Science.gov (United States)

    Bruno, Silvia; Ledda, Bernardetta; Tenca, Claudya; Ravera, Silvia; Orengo, Anna Maria; Mazzarello, Andrea Nicola; Pesenti, Elisa; Casciaro, Salvatore; Racchi, Omar; Ghiotto, Fabio; Marini, Cecilia; Sambuceti, Gianmario; DeCensi, Andrea; Fais, Franco

    2015-09-08

    B-cell chronic lymphocytic leukemia (CLL) was believed to result from clonal accumulation of resting apoptosis-resistant malignant B lymphocytes. However, it became increasingly clear that CLL cells undergo, during their life, iterative cycles of re-activation and subsequent clonal expansion. Drugs interfering with CLL cell cycle entry would be greatly beneficial in the treatment of this disease. 1, 1-Dimethylbiguanide hydrochloride (metformin), the most widely prescribed oral hypoglycemic agent, inexpensive and well tolerated, has recently received increased attention for its potential antitumor activity. We wondered whether metformin has apoptotic and anti-proliferative activity on leukemic cells derived from CLL patients. Metformin was administered in vitro either to quiescent cells or during CLL cell activation stimuli, provided by classical co-culturing with CD40L-expressing fibroblasts. At doses that were totally ineffective on normal lymphocytes, metformin induced apoptosis of quiescent CLL cells and inhibition of cell cycle entry when CLL were stimulated by CD40-CD40L ligation. This cytostatic effect was accompanied by decreased expression of survival- and proliferation-associated proteins, inhibition of signaling pathways involved in CLL disease progression and decreased intracellular glucose available for glycolysis. In drug combination experiments, metformin lowered the apoptotic threshold and potentiated the cytotoxic effects of classical and novel antitumor molecules. Our results indicate that, while CLL cells after stimulation are in the process of building their full survival and cycling armamentarium, the presence of metformin affects this process.

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

    Science.gov (United States)

    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.

  19. Acrolein in cigarette smoke inhibits T-cell responses.

    Science.gov (United States)

    Lambert, Cherie; McCue, Jesica; Portas, Mary; Ouyang, Yanli; Li, JiMei; Rosano, Thomas G; Lazis, Alexander; Freed, Brian M

    2005-10-01

    Cigarette smoking inhibits T-cell responses in the lungs, but the immunosuppressive compounds have not been fully identified. Cigarette smoke extracts inhibit IL-2, IFN-gamma, and TNF-alpha production in stimulated lymphocytes obtained from peripheral blood, even when the extracts were diluted 100-fold to 1000-fold. The objective of these studies was to identify the immunosuppressive compounds found in cigarette smoke. Gas chromatography/mass spectroscopy and HPLC were used to identify and quantitate volatile compounds found in cigarette smoke extracts. Bioactivity was measured by viability and production of cytokine mRNA and protein levels in treated human lymphocytes. The vapor phase of the cigarette smoke extract inhibited cytokine production, indicating that the immunosuppressive compounds were volatile. Among the volatile compounds identified in cigarette smoke extracts, only the alpha,beta-unsaturated aldehydes, acrolein (inhibitory concentration of 50% [IC50] = 3 micromol/L) and crotonaldehyde (IC50 = 6 micromol/L), exhibited significant inhibition of cytokine production. Although the levels of aldehydes varied 10-fold between high-tar (Camel) and ultralow-tar (Carlton) extracts, even ultralow-tar cigarettes produced sufficient levels of acrolein (34 micromol/L) to suppress cytokine production by >95%. We determined that the cigarette smoke extract inhibited transcription of cytokine genes. The inhibitory effects of acrolein could be blocked with the thiol compound N-acetylcysteine. The vapor phase from cigarette smoke extracts potently suppresses cytokine production. The compound responsible for this inhibition appears to be acrolein.

  20. Protective effects of TRH and its analogues against various cytotoxic agents in retinoic acid (RA)-differentiated human neuroblastoma SH-SY5Y cells.

    Science.gov (United States)

    Jaworska-Feil, L; Jantas, D; Leskiewicz, M; Budziszewska, B; Kubera, M; Basta-Kaim, A; Lipkowski, A W; Lason, W

    2010-12-01

    TRH (thyroliberin) and its analogues were reported to possess neuroprotective effects in cellular and animal experimental models of acute and chronic neurodegenerative diseases. In the present study we evaluated effects of TRH and its three stable analogues, montirelin (CG-3703), RGH-2202 and Z-TRH (N-(carbobenzyloxy)-pGlutamyl-Histydyl-Proline) on the neuronally differentiated human neuroblastoma SH-SY5Y cell line, which is widely accepted for studying potential neuroprotectants. We found that TRH and all the tested analogues at concentrations 0.1-50 μM attenuated cell damage induced by MPP(+) (2 mM), 3-nitropropionate (10 mM), hydrogen peroxide (0.5 mM), homocysteine (250 μM) and beta-amyloid (20μM) in retinoic acid differentiated SH-SY5Y cells. Furthermore, we demonstrated that TRH and its analogues decreased the staurosporine (0.5 μM)-induced LDH release, caspase-3 activity and DNA fragmentation, which indicate the anti-apoptotic proprieties of these peptides. The neuroprotective effects of TRH (10 μM) and RGH-2202 (10 μM) on St-induced cell death was attenuated by inhibitors of PI3-K pathway (wortmannin and LY294002), but not MAPK/ERK1/2 (PD98059 and U0126). Moreover, TRH and its analogues at neuroprotective concentrations (1 and 10 μM) increased expression of Bcl-2 protein, as confirmed by Western blot analysis. All in all, these results extend data on neuroprotective properties of TRH and its analogues and provide evidence that mechanism of anti-apoptotic effects of these peptides in SH-SY5Y cell line involves induction of PI3K/Akt pathway and Bcl-2. Furthermore, the data obtained on human cell line with a dopaminergic phenotype suggest potential utility of TRH and its analogues in the treatment of some neurodegenerative diseases including Parkinson's disease. Copyright © 2010 Elsevier Ltd. All rights reserved.

  1. Phytochemicals radiosensitize cancer cells by inhibiting DNA repair

    International Nuclear Information System (INIS)

    Singh, Rana P.

    2017-01-01

    Solid tumors are mostly treated with radiotherapy. Radiotherapy is toxic to normal tissues and also promote the invasiveness and radioresistance in cancer cells. The resistance against radiotherapy and adverse effects to normal cells reduce the overall therapeutic effects of the treatment. Radiosensitizing agents usually show limited success during clinical trials. Therefore, the search and development of new radiosensitizers showing selective response to only cancer cells is desirable. We analyzed the radiosensitizing effects including cell death effect of silibinin, a phytochemical on prostate cancer cells. Silibinin enhanced gamma radiation (2.5-10 Gy) induced inhibition in colony formation selectively in prostate cancer cells. In cell cycle progression, G2/M phase is the most sensitive phase for radiation-induced damage which was delayed by the compound treatment in radiation exposed cells. The lower concentrations of silibinin substantially enhanced radiation-induced apoptosis. A prolonged reactive oxygen species production was also observed in these treatments EGFR signaling pathway can contribute to radiation-induced pro-survival mechanisms and to the therapeutic resistance. Agent treatment reduced the IR-induced EGFR phosphorylation and consequently reversed the resistance mediating mechanisms within the cancer cell. Thus, inhibiting DNA repair in cancer cells would enhance therapeutic response of radiation in cancer cells. Silibinin affected the localization of EGFR and DNA-dependent protein kinase, the DNA-PK is known to be an important mediator of DSB repair in human cells, and showed increased number of pH2AX (ser139) foci, and thus indicating lower DNA repair in these cancer cells. This was also confirmed in the tumor xenograft study. Our findings suggest that a combination of silibinin with radiation could be an effective treatment of radioresistant human prostate cancer and warrants further investigation. (author)

  2. XIAP antagonist embelin inhibited proliferation of cholangiocarcinoma cells.

    Directory of Open Access Journals (Sweden)

    Cody J Wehrkamp

    Full Text Available Cholangiocarcinoma cells are dependent on antiapoptotic signaling for survival and resistance to death stimuli. Recent mechanistic studies have revealed that increased cellular expression of the E3 ubiquitin-protein ligase X-linked inhibitor of apoptosis (XIAP impairs TRAIL- and chemotherapy-induced cytotoxicity, promoting survival of cholangiocarcinoma cells. This study was undertaken to determine if pharmacologic antagonism of XIAP protein was sufficient to sensitize cholangiocarcinoma cells to cell death. We employed malignant cholangiocarcinoma cell lines and used embelin to antagonize XIAP protein. Embelin treatment resulted in decreased XIAP protein levels by 8 hours of treatment with maximal effect at 16 hours in KMCH and Mz-ChA-1 cells. Assessment of nuclear morphology demonstrated a concentration-dependent increase in nuclear staining. Interestingly, embelin induced nuclear morphology changes as a single agent, independent of the addition of TNF-related apoptosis inducing ligand (TRAIL. However, caspase activity assays revealed that increasing embelin concentrations resulted in slight inhibition of caspase activity, not activation. In addition, the use of a pan-caspase inhibitor did not prevent nuclear morphology changes. Finally, embelin treatment of cholangiocarcinoma cells did not induce DNA fragmentation or PARP cleavage. Apoptosis does not appear to contribute to the effects of embelin on cholangiocarcinoma cells. Instead, embelin caused inhibition of cell proliferation and cell cycle analysis indicated that embelin increased the number of cells in S and G2/M phase. Our results demonstrate that embelin decreased proliferation in cholangiocarcinoma cell lines. Embelin treatment resulted in decreased XIAP protein expression, but did not induce or enhance apoptosis. Thus, in cholangiocarcinoma cells the mechanism of action of embelin may not be dependent on apoptosis.

  3. Elaeocarpusin Inhibits Mast Cell-Mediated Allergic Inflammation

    Directory of Open Access Journals (Sweden)

    Min-Jong Kim

    2018-06-01

    Full Text Available Mast cells are major effector cells for allergic responses that act by releasing inflammatory mediators, such as histamine and pro-inflammatory cytokines. Accordingly, different strategies have been pursued to develop anti-allergic and anti-inflammatory candidates by regulating the function of mast cells. The purpose of this study was to determine the effectiveness of elaeocarpusin (EL on mast cell-mediated allergic inflammation. We isolated EL from Elaeocarpus sylvestris L. (Elaeocarpaceae, which is known to possess anti-inflammatory properties. For this study, various sources of mast cells and mouse anaphylaxis models were used. EL suppressed the induction of markers for mast cell degranulation, such as histamine and β-hexosaminidase, by reducing intracellular calcium levels. Expression of pro-inflammatory cytokines, such as tumor necrosis factor-α and IL-4, was significantly decreased in activated mast cells by EL. This inhibitory effect was related to inhibition of the phosphorylation of Fyn, Lyn, Syk, and Akt, and the nuclear translocation of nuclear factor-κB. To confirm the effect of EL in vivo, immunoglobulin E-mediated passive cutaneous anaphylaxis (PCA and ovalbumin-induced active systemic anaphylaxis (ASA models were induced. EL reduced the PCA reaction in a dose dependent manner. In addition, EL attenuated ASA reactions such as hypothemia, histamine release, and IgE production. Our results suggest that EL is a potential therapeutic candidate for allergic inflammatory diseases that acts via the inhibition of mast cell degranulation and expression of proinflammatory cytokines.

  4. Inhibition of glycolysis by misonidazole in hypoxic cells

    International Nuclear Information System (INIS)

    Ling, L.; Sutherland, R.

    1984-01-01

    Inhibition of glycolysis has been postulated to be a mechanism of misonidazole (MISO) toxicity in hypoxic cells. To investigate the effect of MISO on glycolysis, glucose transport and its consumption and lactate formation were measured. Exponential EMT6 cells (10/sup 6/ cells/ml) were made hypoxix by continuous gassing in 3% CO/sub 2/ in N/sub 2/. They were then treated with 5mM MISO for various times, then washed and analysed for their rates of anaerobic glycolysis. Glucose and lactate content were determined enzymatically. The rates of both glucose consumption and lactate formation decreased after 30 min hypoxic incubation with MISO. After 90 min, the rates were not measurable even though the cells still excluded Trypan Blue. There was, however, a parallel decrease in plating efficiency. These data suggest that the inhibition of glycolysis is an important mechanism of hypoxic toxicity of MISO. To locate the site of inhibition, studies were initiated to look at glucose transport by following the uptake of /sup 14/-C-3-0-methyl-glucose, a nonmetabolised glucose analog. Results obtained so far indicate that up to 90 min of hypoxic incubation with MISO, there was no change in the kinetics of the uptake of his analog. Therefore, the results showed that in hypoxic cells treated with MISO, the glucose transport system was unaffected. However, there was a rapid decrease in anaerobic glycolysis

  5. RNA interference targeting raptor inhibits proliferation of gastric cancer cells

    International Nuclear Information System (INIS)

    Wu, William Ka Kei; Lee, Chung Wa; Cho, Chi Hin; Chan, Francis Ka Leung; Yu, Jun; Sung, Joseph Jao Yiu

    2011-01-01

    Mammalian target of rapamycin complex 1 (mTORC1) is dysregulated in gastric cancer. The biologic function of mTORC1 in gastric carcinogenesis is unclear. Here, we demonstrate that disruption of mTORC1 function by RNA interference-mediated downregulation of raptor substantially inhibited gastric cancer cell proliferation through induction of G 0 /G 1 -phase cell cycle arrest. The anti-proliferative effect was accompanied by concomitant downregulation of activator protein-1 and upregulation of Smad2/3 transcriptional activities. In addition, the expression of cyclin D 3 and p21 Waf1 , which stabilizes cyclin D/cdk4 complex for G 1 -S transition, was reduced by raptor knockdown. In conclusion, disruption of mTORC1 inhibits gastric cancer cell proliferation through multiple pathways. This discovery may have an implication in the application of mTORC1-directed therapy for the treatment of gastric cancer.

  6. The sensitivity of an actinic reticuloid cell strain to near-ultraviolet radiation and its modification by Trolox-C, a vitamin E analogue

    International Nuclear Information System (INIS)

    Kralli, A.; Moss, S.H.

    1987-01-01

    Near-UV radiation (365 nm)-induced lethality, as measured by colony-forming ability, showed an actinic reticuloid cell strain to be sensitive relative to normal human fibroblasts, when irradiated at 25 0 C. This effect was not seen after far-UV (254 nm) irradiation. Trolox-C, a water-soluble analogue of vitamin E, incorporated in the pre-irradiation growth medium or in the post-irradiation plating medium, protected the actinic reticuloid cells to the extent that they were as resistant as normal cells. Plating medium containing Trolox-C did not provide differential protection against inactivation of the two cell strains by wavelengths in the far-UV region. The protection provided by Trolox-C, an analogue of the natural antioxidant vitamin E, suggests some free radical involvement in the aetiology of the disease. (author)

  7. Radiosensitization of colorectal carcinoma cell lines by histone deacetylase inhibition

    International Nuclear Information System (INIS)

    Flatmark, Kjersti; Nome, Ragnhild V; Folkvord, Sigurd; Bratland, Åse; Rasmussen, Heidi; Ellefsen, Mali Strand; Fodstad, Øystein; Ree, Anne Hansen

    2006-01-01

    The tumor response to preoperative radiotherapy of locally advanced rectal cancer varies greatly, warranting the use of experimental models to assay the efficacy of molecular targeting agents in rectal cancer radiosensitization. Histone deacetylase (HDAC) inhibitors, agents that cause hyperacetylation of histone proteins and thereby remodeling of chromatin structure, may override cell cycle checkpoint responses to DNA damage and amplify radiation-induced tumor cell death. Human colorectal carcinoma cell lines were exposed to ionizing radiation and HDAC inhibitors, and cell cycle profiles and regulatory factors, as well as clonogenicity, were analyzed. In addition to G 2 /M phase arrest following irradiation, the cell lines displayed cell cycle responses typical for either intact or defective p53 function (the presence or absence, respectively, of radiation-induced expression of the cell cycle inhibitor p21 and subsequent accumulation of G 1 phase cells). In contrast, histone acetylation was associated with complete depletion of the G 1 population of cells with functional p53 but accumulation of both G 1 and G 2 /M populations of cells with defective p53. The cellular phenotypes upon HDAC inhibition were consistent with the observed repression of Polo-like kinase-1, a regulatory G 2 /M phase kinase. Following pre-treatment with HDAC inhibitors currently undergoing clinical investigation, the inhibitory effect of ionizing radiation on clonogenicity was significantly amplified. In these experimental models, HDAC inhibition sensitized the tumor cells to ionizing radiation, which is in accordance with the concept of increased probability of tumor cell death when chromatin structure is modified

  8. An antitubulin agent BCFMT inhibits proliferation of cancer cells and induces cell death by inhibiting microtubule dynamics.

    Directory of Open Access Journals (Sweden)

    Ankit Rai

    Full Text Available Using cell based screening assay, we identified a novel anti-tubulin agent (Z-5-((5-(4-bromo-3-chlorophenylfuran-2-ylmethylene-2-thioxothiazolidin-4-one (BCFMT that inhibited proliferation of human cervical carcinoma (HeLa (IC(50, 7.2 ± 1.8 µM, human breast adenocarcinoma (MCF-7 (IC(50, 10.0 ± 0.5 µM, highly metastatic breast adenocarcinoma (MDA-MB-231 (IC(50, 6.0 ± 1 µM, cisplatin-resistant human ovarian carcinoma (A2780-cis (IC(50, 5.8 ± 0.3 µM and multi-drug resistant mouse mammary tumor (EMT6/AR1 (IC(50, 6.5 ± 1 µM cells. Using several complimentary strategies, BCFMT was found to inhibit cancer cell proliferation at G2/M phase of the cell cycle apparently by targeting microtubules. In addition, BCFMT strongly suppressed the dynamics of individual microtubules in live MCF-7 cells. At its half maximal proliferation inhibitory concentration (10 µM, BCFMT reduced the rates of growing and shortening phases of microtubules in MCF-7 cells by 37 and 40%, respectively. Further, it increased the time microtubules spent in the pause (neither growing nor shortening detectably state by 135% and reduced the dynamicity (dimer exchange per unit time of microtubules by 70%. In vitro, BCFMT bound to tubulin with a dissociation constant of 8.3 ± 1.8 µM, inhibited tubulin assembly and suppressed GTPase activity of microtubules. BCFMT competitively inhibited the binding of BODIPY FL-vinblastine to tubulin with an inhibitory concentration (K(i of 5.2 ± 1.5 µM suggesting that it binds to tubulin at the vinblastine site. In cultured cells, BCFMT-treatment depolymerized interphase microtubules, perturbed the spindle organization and accumulated checkpoint proteins (BubR1 and Mad2 at the kinetochores. BCFMT-treated MCF-7 cells showed enhanced nuclear accumulation of p53 and its downstream p21, which consequently activated apoptosis in these cells. The results suggested that BCFMT inhibits proliferation of several types of cancer cells including drug

  9. Sickle erythrocytes inhibit human endothelial cell DNA synthesis

    International Nuclear Information System (INIS)

    Weinstein, R.; Zhou, M.A.; Bartlett-Pandite, A.; Wenc, K.

    1990-01-01

    Patients with sickle cell anemia experience severe vascular occlusive phenomena including acute pain crisis and cerebral infarction. Obstruction occurs at both the microvascular and the arterial level, and the clinical presentation of vascular events is heterogeneous, suggesting a complex etiology. Interaction between sickle erythrocytes and the endothelium may contribute to vascular occlusion due to alteration of endothelial function. To investigate this hypothesis, human vascular endothelial cells were overlaid with sickle or normal erythrocytes and stimulated to synthesize DNA. The erythrocytes were sedimented onto replicate monolayers by centrifugation for 10 minutes at 17 g to insure contact with the endothelial cells. Incorporation of 3H-thymidine into endothelial cell DNA was markedly inhibited during contact with sickle erythrocytes. This inhibitory effect was enhanced more than twofold when autologous sickle plasma was present during endothelial cell labeling. Normal erythrocytes, with or without autologous plasma, had a modest effect on endothelial cell DNA synthesis. When sickle erythrocytes in autologous sickle plasma were applied to endothelial monolayers for 1 minute, 10 minutes, or 1 hour and then removed, subsequent DNA synthesis by the endothelial cells was inhibited by 30% to 40%. Although adherence of sickle erythrocytes to the endothelial monolayers was observed under these experimental conditions, the effect of sickle erythrocytes on endothelial DNA synthesis occurred in the absence of significant adherence. Hence, human endothelial cell DNA synthesis is partially inhibited by contact with sickle erythrocytes. The inhibitory effect of sickle erythrocytes occurs during a brief (1 minute) contact with the endothelial monolayers, and persists for at least 6 hours of 3H-thymidine labeling

  10. Intraglomerular inhibition maintains mitral cell response contrast across input frequencies.

    Science.gov (United States)

    Shao, Zuoyi; Puche, Adam C; Shipley, Michael T

    2013-11-01

    Odor signals are transmitted to the olfactory bulb by olfactory nerve (ON) synapses onto mitral/tufted cells (MTCs) and external tufted cells (ETCs); ETCs provide additional feed-forward excitation to MTCs. Both are strongly regulated by intraglomerular inhibition that can last up to 1 s and, when blocked, dramatically increases ON-evoked MC spiking. Intraglomerular inhibition thus limits the magnitude and duration of MC spike responses to sensory input. In vivo, sensory input is repetitive, dictated by sniffing rates from 1 to 8 Hz, potentially summing intraglomerular inhibition. To investigate this, we recorded MTC responses to 1- to 8-Hz ON stimulation in slices. Inhibitory postsynaptic current area (charge) following each ON stimulation was unchanged from 1 to 5 Hz and modestly paired-pulse attenuated at 8 Hz, suggesting there is no summation and only limited decrement at the highest input frequencies. Next, we investigated frequency independence of intraglomerular inhibition on MC spiking. MCs respond to single ON shocks with an initial spike burst followed by reduced spiking decaying to baseline. Upon repetitive ON stimulation peak spiking is identical across input frequencies but the ratio of peak-to-minimum rate before the stimulus (max-min) diminishes from 30:1 at 1 Hz to 15:1 at 8 Hz. When intraglomerular inhibition is selectively blocked, peak spike rate is unchanged but trough spiking increases markedly decreasing max-min firing ratios from 30:1 at 1 Hz to 2:1 at 8 Hz. Together, these results suggest intraglomerular inhibition is relatively frequency independent and can "sharpen" MC responses to input across the range of frequencies. This suggests that glomerular circuits can maintain "contrast" in MC encoding during sniff-sampled inputs.

  11. Canine tracheal epithelial cells are more sensitive than rat tracheal epithelial cells to transforming growth factor beta induced growth inhibition

    International Nuclear Information System (INIS)

    Hubbs, A.F.; Hahn, F.F.; Kelly, G.; Thomassen, D.G.

    1988-01-01

    Transforming growth factor beta (TGFβ) markedly inhibited growth of canine tracheal epithelial (CTE) cells. Reduced responsiveness to TGFβ-induced growth inhibition accompanied neoplastic progression of these cells from primary to transformed to neoplastic. This was similar to the relationship between neoplastic progression and increased resistance to TGFβ-induced growth inhibition seen for rat tracheal epithelial (RTE) cells. The canine cells were more sensitive than rat cells to TGFβ-induced growth inhibition at all stages in the neoplastic process. (author)

  12. Rapamycin inhibits poly(ADP-ribosyl)ation in intact cells

    International Nuclear Information System (INIS)

    Fahrer, Joerg; Wagner, Silvia; Buerkle, Alexander; Koenigsrainer, Alfred

    2009-01-01

    Rapamycin is an immunosuppressive drug, which inhibits the mammalian target of rapamycin (mTOR) kinase activity inducing changes in cell proliferation. Synthesis of poly(ADP-ribose) (PAR) is an immediate cellular response to genotoxic stress catalyzed mostly by poly(ADP-ribose) polymerase 1 (PARP-1), which is also controlled by signaling pathways. Therefore, we investigated whether rapamycin affects PAR production. Strikingly, rapamycin inhibited PAR synthesis in living fibroblasts in a dose-dependent manner as monitored by immunofluorescence. PARP-1 activity was then assayed in vitro, revealing that down-regulation of cellular PAR production by rapamycin was apparently not due to competitive PARP-1 inhibition. Further studies showed that rapamycin did not influence the cellular NAD pool and the activation of PARP-1 in extracts of pretreated fibroblasts. Collectively, our data suggest that inhibition of cellular PAR synthesis by rapamycin is mediated by formation of a detergent-sensitive complex in living cells, and that rapamycin may have a potential as therapeutic PARP inhibitor.

  13. Rapamycin inhibits poly(ADP-ribosyl)ation in intact cells

    Energy Technology Data Exchange (ETDEWEB)

    Fahrer, Joerg, E-mail: joerg.fahrer@uni-ulm.de [Molecular Toxicology Group, Department of Biology, University of Konstanz (Germany); Wagner, Silvia [Clinic of General, Visceral- and Transplantation Surgery, ZMF, University Hospital Tuebingen (Germany); Buerkle, Alexander [Molecular Toxicology Group, Department of Biology, University of Konstanz (Germany); Koenigsrainer, Alfred [Clinic of General, Visceral- and Transplantation Surgery, ZMF, University Hospital Tuebingen (Germany)

    2009-08-14

    Rapamycin is an immunosuppressive drug, which inhibits the mammalian target of rapamycin (mTOR) kinase activity inducing changes in cell proliferation. Synthesis of poly(ADP-ribose) (PAR) is an immediate cellular response to genotoxic stress catalyzed mostly by poly(ADP-ribose) polymerase 1 (PARP-1), which is also controlled by signaling pathways. Therefore, we investigated whether rapamycin affects PAR production. Strikingly, rapamycin inhibited PAR synthesis in living fibroblasts in a dose-dependent manner as monitored by immunofluorescence. PARP-1 activity was then assayed in vitro, revealing that down-regulation of cellular PAR production by rapamycin was apparently not due to competitive PARP-1 inhibition. Further studies showed that rapamycin did not influence the cellular NAD pool and the activation of PARP-1 in extracts of pretreated fibroblasts. Collectively, our data suggest that inhibition of cellular PAR synthesis by rapamycin is mediated by formation of a detergent-sensitive complex in living cells, and that rapamycin may have a potential as therapeutic PARP inhibitor.

  14. Angiopoietin1 inhibits mast cell activation and protects against anaphylaxis.

    Directory of Open Access Journals (Sweden)

    Jun-Hua Yao

    Full Text Available Since morbidity and mortality rates of anaphylaxis diseases have been increasing year by year, how to prevent and manage these diseases effectively has become an important issue. Mast cells play a central regulatory role in allergic diseases. Angiopoietin1 (Ang-1 exhibits anti-inflammatory properties by inhibiting vascular permeability, leukocyte migration and cytokine production. However, Ang-1's function in mast cell activation and anaphylaxis diseases is unknown. The results of our study suggest that Ang-1 decreased lipopolysaccharide (LPS-induced pro-inflammatory cytokines production of mast cells by suppressing IκB phosphorylation and NF-κB nuclear translocation. Ang-1 also strongly inhibited compound 48/80 induced and FcεRI-mediated mast cells degranulation by decreasing intracellular calcium levels in vitro. In vivo lentivirus-mediated delivery of Ang-1 in mice exhibited alleviated leakage in IgE-dependent passive cutaneous anaphylaxis (PCA. Furthermore, exogenous Ang-1 intervention treatment prevented mice from compound 48/80-induced mesentery mast cell degranulation, attenuated increases in pro-inflammatory cytokines, relieved lung injury, and improved survival in anaphylaxis shock. The results of our study reveal, for the first time, the important role of Ang-1 in the activation of mast cells, and identify a therapeutic effect of Ang-1 on anaphylaxis diseases.

  15. Barium inhibits arsenic-mediated apoptotic cell death in human squamous cell carcinoma cells.

    Science.gov (United States)

    Yajima, Ichiro; Uemura, Noriyuki; Nizam, Saika; Khalequzzaman, Md; Thang, Nguyen D; Kumasaka, Mayuko Y; Akhand, Anwarul A; Shekhar, Hossain U; Nakajima, Tamie; Kato, Masashi

    2012-06-01

    Our fieldwork showed more than 1 μM (145.1 μg/L) barium in about 3 μM (210.7 μg/L) arsenic-polluted drinking well water (n = 72) in cancer-prone areas in Bangladesh, while the mean concentrations of nine other elements in the water were less than 3 μg/L. The types of cancer include squamous cell carcinomas (SCC). We hypothesized that barium modulates arsenic-mediated biological effects, and we examined the effect of barium (1 μM) on arsenic (3 μM)-mediated apoptotic cell death of human HSC-5 and A431 SCC cells in vitro. Arsenic promoted SCC apoptosis with increased reactive oxygen species (ROS) production and JNK1/2 and caspase-3 activation (apoptotic pathway). In contrast, arsenic also inhibited SCC apoptosis with increased NF-κB activity and X-linked inhibitor of apoptosis protein (XIAP) expression level and decreased JNK activity (antiapoptotic pathway). These results suggest that arsenic bidirectionally promotes apoptotic and antiapoptotic pathways in SCC cells. Interestingly, barium in the presence of arsenic increased NF-κB activity and XIAP expression and decreased JNK activity without affecting ROS production, resulting in the inhibition of the arsenic-mediated apoptotic pathway. Since the anticancer effect of arsenic is mainly dependent on cancer apoptosis, barium-mediated inhibition of arsenic-induced apoptosis may promote progression of SCC in patients in Bangladesh who keep drinking barium and arsenic-polluted water after the development of cancer. Thus, we newly showed that barium in the presence of arsenic might inhibit arsenic-mediated cancer apoptosis with the modulation of the balance between arsenic-mediated promotive and suppressive apoptotic pathways.

  16. Synthesis, antitumour and antioxidant activities of novel α,β-unsaturated ketones and related heterocyclic analogues: EGFR inhibition and molecular modelling study.

    Science.gov (United States)

    El-Husseiny, Walaa M; El-Sayed, Magda A-A; Abdel-Aziz, Naglaa I; El-Azab, Adel S; Ahmed, Esam R; Abdel-Aziz, Alaa A-M

    2018-12-01

    New α,β-unsaturated ketones 4a,b; 5a-c; and 6a,b; as well as 4-H pyran 7; pyrazoline 8a,b; isoxazoline 9; pyridine 10-11; and quinoline-4-carboxylic acid 12a,b derivatives were synthesized and evaluated for in vitro antitumour activity against HepG2, MCF-7, HeLa, and PC-3 cancer cell lines. Antioxidant activity was investigated by the ability of these compounds to scavenge the 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) radical cation (ABTS •+ ). Compounds 6a, 6b, 7, and 8b exhibited potent antitumour activities against all tested cell lines with [IC 50 ] ≅5.5-18.1 µΜ), in addition to significantly high ABTS •+ scavenging activities. In vitro EGFR kinase assay for 6a, 6b, 7, and 8b as the most potent antitumour compounds showed that; compounds 6b, and 7 exhibited worthy EGFR inhibition activity with IC 50 values of 0.56 and 1.6 µM, respectively, while compounds 6a and 8b showed good inhibition activity with IC 50 values of 4.66 and 2.16 µM, respectively, compared with sorafenib reference drug (IC 50  = 1.28 µM). Molecular modelling studies for compounds 6b, 7, and 8b were conducted to exhibit the binding mode towards EGFR kinase, which showed similar interaction with erlotinib.

  17. Clonal cell populations unresponsive to radiosensitization induced by telomerase inhibition

    International Nuclear Information System (INIS)

    Ju, Yeun-Jin; Shin, Hyun-Jin; Park, Jeong-Eun; Juhn, Kyoung-Mi; Woo, Seon Rang; Kim, Hee-Young; Han, Young-Hoon; Hwang, Sang-Gu; Hong, Sung-Hee; Kang, Chang-Mo; Yoo, Young-Do; Park, Won-Bong; Cho, Myung-Haing; Park, Gil Hong; Lee, Kee-Ho

    2010-01-01

    Research highlights: → In our present manuscript, we have clearly showed an interesting but problematic obstacle of a radiosensitization strategy based on telomerase inhibition by showing that: Clonal population unresponsive to this radiosensitization occasionally arise. → The telomere length of unsensitized clones was reduced, as was that of most sensitized clones. → The unsensitized clones did not show chromosome end fusion which was noted in all sensitized clones. → P53 status is not associated with the occurrence of unsensitized clone. → Telomere end capping in unsensitized clone is operative even under telomerase deficiency. -- Abstract: A combination of a radiotherapeutic regimen with telomerase inhibition is valuable when tumor cells are to be sensitized to radiation. Here, we describe cell clones unresponsive to radiosensitization after telomere shortening. After extensive division of individual transformed clones of mTERC -/- cells, about 22% of clones were unresponsive to radiosensitization even though telomerase action was inhibited. The telomere lengths of unsensitized mTERC -/- clones were reduced, as were those of most sensitized clones. However, the unsensitized clones did not exhibit chromosomal end-to-end fusion to the extent noted in all sensitized clones. Thus, a defense mechanism preventing telomere erosion is operative even when telomeres become shorter under conditions of telomerase deficiency, and results in unresponsiveness to the radiosensitization generally mediated by telomere shortening.

  18. Gimeracil sensitizes cells to radiation via inhibition of homologous recombination

    International Nuclear Information System (INIS)

    Takagi, Masaru; Sakata, Koh-ichi; Someya, Masanori; Tauchi, Hiroshi; Iijima, Kenta; Matsumoto, Yoshihisa; Torigoe, Toshihiko; Takahashi, Akari; Hareyama, Masato; Fukushima, Masakazu

    2010-01-01

    Background and purpose: 5-Chloro-2,4-dihydroxypyridine (Gimeracil) is a component of an oral fluoropyrimidine derivative S-1. Gimeracil is originally added to S-1 to yield prolonged 5-FU concentrations in tumor tissues by inhibiting dihydropyrimidine dehydrogenase, which degrades 5-FU. We found that Gimeracil by itself had the radiosensitizing effect. Methods and materials: We used various cell lines deficient in non-homologous end-joining (NHEJ) or homologous recombination (HR) as well as DLD-1 and HeLa in clonogenic assay. γ-H2AX focus formation and SCneo assay was performed to examine the effects of Gimeracil on DNA double strand break (DSB) repair mechanisms. Results: Results of γ-H2AX focus assay indicated that Gimeracil inhibited DNA DSB repair. It did not sensitize cells deficient in HR but sensitized those deficient in NHEJ. In SCneo assay, Gimeracil reduced the frequency of neo-positive clones. Additionally, it sensitized the cells in S-phase more than in G0/G1. Conclusions: Gimeracil inhibits HR. Because HR plays key roles in the repair of DSBH caused by radiotherapy, Gimeracil may enhance the efficacy of radiotherapy through the suppression of HR-mediated DNA repair pathways.

  19. Caffeine inhibits cell proliferation by G0/G1 phase arrest in JB6 cells.

    Science.gov (United States)

    Hashimoto, Takashi; He, Zhiwei; Ma, Wei-Ya; Schmid, Patricia C; Bode, Ann M; Yang, Chung S; Dong, Zigang

    2004-05-01

    Caffeine is a major biologically active constituent in coffee and tea. Because caffeine has been reported to inhibit carcinogenesis in UVB-exposed mice, the cancer-preventing effect of caffeine has attracted considerable attention. In the present study, the effect of caffeine in quiescent (G0 phase) cells was investigated. Pretreatment with caffeine suppressed cell proliferation in a dose-dependent manner 36 h after addition of fetal bovine serum as a cell growth stimulator. Analysis by flow cytometry showed that caffeine suppressed cell cycle progression at the G0/G1 phase, i.e., 18 h after addition of fetal bovine serum, the percentages of cells in G0/G1 phase in 1 mM caffeine-treated cells and in caffeine-untreated cells were 61.7 and 29.0, respectively. The percentage of cells in G0/G1 phase at 0 h was 75.5. Caffeine inhibited phosphorylation of retinoblastoma protein at Ser780 and Ser807/Ser811, the sites where retinoblastoma protein has been reported to be phosphorylated by cyclin-dependent kinase 4 (cdk4). Furthermore, caffeine inhibited the activation of the cyclin D1-cdk4 complex in a dose-dependent manner. However this compound did not directly inhibit the activity of this complex. In addition, caffeine did not affect p16INK4 or p27Kip1 protein levels, but inhibited the phosphorylation of protein kinase B (Akt) and glycogen synthase kinase 3beta. Our results showed that caffeine suppressed the progression of quiescent cells into the cell cycle. The inhibitory mechanism may be due to the inhibition of cell growth signal-induced activation of cdk4, which may be involved in the inhibition of carcinogenesis in vivo.

  20. Arecoline inhibits endothelial cell growth and migration and the attachment to mononuclear cells

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    Shuei-Kuen Tseng

    2014-09-01

    Conclusion: Arecoline impaired vascular endothelial cells by inhibiting their growth and migration and their adhesion to U937 mononuclear cells. These results reveal that arecoline may contribute to the pathogenesis of oral submucous fibrosis and cardiovascular diseases by affecting endothelial cell function in BQ chewers.

  1. Miltefosine inhibits Candida albicans and non-albicans Candida spp. biofilms and impairs the dispersion of infectious cells.

    Science.gov (United States)

    Vila, Taissa; Ishida, Kelly; Seabra, Sergio Henrique; Rozental, Sonia

    2016-11-01

    Candida spp. can adhere to and form biofilms over different surfaces, becoming less susceptible to antifungal treatment. Resistance of biofilms to antifungal agents is multifactorial and the extracellular matrix (ECM) appears to play an important role. Among the few available antifungals for treatment of candidaemia, only the lipid formulations of amphotericin B (AmB) and the echinocandins are effective against biofilms. Our group has previously demonstrated that miltefosine has an important effect against Candida albicans biofilms. Thus, the aim of this work was to expand the analyses of the in vitro antibiofilm activity of miltefosine to non-albicans Candida spp. Miltefosine had significant antifungal activity against planktonic cells and the development of biofilms of C. albicans, Candida parapsilosis, Candida tropicalis and Candida glabrata. The activity profile in biofilms was superior to fluconazole and was similar to that of AmB and caspofungin. Biofilm-derived cells with their ECM extracted became as susceptible to miltefosine as planktonic cells, confirming the importance of the ECM in the biofilm resistant behaviour. Miltefosine also inhibited biofilm dispersion of cells at the same concentration needed to inhibit planktonic cell growth. The data obtained in this work reinforce the potent inhibitory activity of miltefosine on biofilms of the four most pathogenic Candida spp. and encourage further studies for the utilisation of this drug and/or structural analogues on biofilm-related infections. Copyright © 2016 Elsevier B.V. and International Society of Chemotherapy. All rights reserved.

  2. Inhibiting prenylation augments chemotherapy efficacy in renal cell carcinoma through dual inhibition on mitochondrial respiration and glycolysis.

    Science.gov (United States)

    Huang, Jiangrong; Yang, Xiaoyu; Peng, Xiaochun; Huang, Wei

    2017-11-18

    Prenylation is a posttranslational lipid modification required for the proper functions of a number of proteins involved in cell regulation. Here, we show that prenylation inhibition is important for renal cell carcinoma (RCC) growth, survival and response to chemotherapy, and its underlying mechanism may be contributed to mitochondrial dysfunction. We first demonstrated that a HMG-CoA reductase inhibitor pitavastatin inhibited mevalonate pathway and thereby prenylation in RCC cells. In addition, pitavastatin is effective in inhibiting growth and inducing apoptosis in a panel of RCC cell lines. Combination of pitavastatin and paclitaxel is significantly more effective than pitavastatin or paclitaxel alone as shown by both in vitro cell culture system and in vivo RCC xenograft model. Importantly, pitavastatin treatment inhibits mitochondrial respiration via suppressing mitochondrial complex I and II enzyme activities. Interestingly, different from mitochondrial inhibitor phenformin that inhibits mitochondrial respiration but activates glycolytic rate in RCC cells, pitavastatin significantly decreases glycolytic rate. The dual inhibitory action of pitavastatin on mitochondrial respiration and glycolysis results in remarkable energy depletion and oxidative stress in RCC cells. In addition, inhibition of prenylation by depleting Isoprenylcysteine carboxylmethyltransferase (Icmt) also mimics the inhibitory effects of pitavastatin in RCC cells. Our work demonstrates the previously unappreciated association between prenylation inhibition and energy metabolism in RCC, which can be therapeutically exploited, likely in tumors that largely rely on energy metabolism. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. Andrographolide and analogues in cancer prevention.

    Science.gov (United States)

    Mishra, Siddhartha Kumar; Tripathi, Swati; Shukla, Archana; Oh, Seung Hyun; Kim, Hwan Mook

    2015-01-01

    Andrographis paniculata is a medicinal plant traditionally used for treatment of cough and cold, fever, laryngitis, and several infectious diseases. Extracts of A. paniculata have shown versatile potency against various diseases including cancer. The active biomolecules of A. paniculata mainly are lactone and diterpene. Andrographolide and analogues have been widely used for prevention of different diseases. Andrographolides have shown potent antiinflammatory and anticancer activities. It showed potentials as chemopreventive agents by suppressing growth of cancer cells by inhibiting NF-kappaB, PI3K/AKT and other kinase pathways and by inducing apoptosis. Andrographolide induced both intrinsic and extrinsic apoptosis pathway in different cancer cells via expression of different anti-apoptotic protein like Bax, p53, and activated caspases. Andrographolide was successfully used as an antineoplastic drug in cancer chemotherapy. Andrographolide inhibited the growth of human breast, prostate, and hepatoma tumors. Andrographolide and analogues need to be subjected to further clinical and biomedical studies in cancer chemoprevention. Andrographolide could be potent anticancer agent when used in combination with other chemotherapeutic agents.

  4. Pumpkin seed extract: Cell growth inhibition of hyperplastic and cancer cells, independent of steroid hormone receptors.

    Science.gov (United States)

    Medjakovic, Svjetlana; Hobiger, Stefanie; Ardjomand-Woelkart, Karin; Bucar, Franz; Jungbauer, Alois

    2016-04-01

    Pumpkin seeds have been known in folk medicine as remedy for kidney, bladder and prostate disorders since centuries. Nevertheless, pumpkin research provides insufficient data to back up traditional beliefs of ethnomedical practice. The bioactivity of a hydro-ethanolic extract of pumpkin seeds from the Styrian pumpkin, Cucurbita pepo L. subsp. pepo var. styriaca, was investigated. As pumpkin seed extracts are standardized to cucurbitin, this compound was also tested. Transactivational activity was evaluated for human androgen receptor, estrogen receptor and progesterone receptor with in vitro yeast assays. Cell viability tests with prostate cancer cells, breast cancer cells, colorectal adenocarcinoma cells and a hyperplastic cell line from benign prostate hyperplasia tissue were performed. As model for non-hyperplastic cells, effects on cell viability were tested with a human dermal fibroblast cell line (HDF-5). No transactivational activity was found for human androgen receptor, estrogen receptor and progesterone receptor, for both, extract and cucurbitin. A cell growth inhibition of ~40-50% was observed for all cell lines, with the exception of HDF-5, which showed with ~20% much lower cell growth inhibition. Given the receptor status of some cell lines, a steroid-hormone receptor independent growth inhibiting effect can be assumed. The cell growth inhibition for fast growing cells together with the cell growth inhibition of prostate-, breast- and colon cancer cells corroborates the ethnomedical use of pumpkin seeds for a treatment of benign prostate hyperplasia. Moreover, due to the lack of androgenic activity, pumpkin seed applications can be regarded as safe for the prostate. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

  5. ERβ inhibits proliferation and invasion of breast cancer cells

    Science.gov (United States)

    Lazennec, Gwendal; Bresson, Damien; Lucas, Annick; Chauveau, Corine; Vignon, Françoise

    2001-01-01

    Recent studies indicate that the expression of ERβ in breast cancer is lower than in normal breast, suggesting that ERβ could play an important role in carcinogenesis. To investigate this hypothesis, we engineered estrogen-receptor negative MDA-MB-231 breast cancer cells to reintroduce either ERα or ERβ protein with an adenoviral vector. In these cells, ERβ (as ERα) expression was monitored using RT-PCR and Western blot. ERβ protein was localized in the nucleus (immunocytochemistry) and able to transactivate estrogen-responsive reporter constructs in the presence of estradiol. ERβ and ERα induced the expression of several endogenous genes such as pS2, TGFα or the cyclin kinase inhibitor p21, but in contrast to ERα, ERβ was unable to regulate c-myc proto-oncogene expression. The pure antiestrogen ICI 164, 384 completely blocked ERα and ERβ estrogen-induced activities. ERβ inhibited MDA-MB-231 cell proliferation in a ligand-independent manner, whereas ERα inhibition of proliferation is hormone-dependent. Moreover, ERβ and ERα, decreased cell motility and invasion. Our data bring the first evidence that ERβ is an important modulator of proliferation and invasion of breast cancer cells and support the hypothesis that the loss of ERβ expression could be one of the events leading to the development of breast cancer. PMID:11517191

  6. Methods to Evaluate the Effect of Ethanol on the Folate Analogue: Fluorescein Methotrexate Uptake in Human Proximal Tubular Cells

    Directory of Open Access Journals (Sweden)

    Sivakumar JT Gowder

    2009-01-01

    Full Text Available Ethanol-induced folate deficiency is due to effects of ethanol on folate metabolism and absorption. We have already shown by using different methods that ethanol interferes with reabsorption of folate from the proximal tubule. In this study, we have used the folate analogue, the fluorescein methotrexate (FL-MTX, in order to evaluate effects of ethanol on FL-MTX uptake by the human proximal tubular (HPT cells by using a confocal microscope and fluoroskan microplate reader. Since endothelins (ETs play a major role in a number of diseases and also in the damage induced by a variety of chemicals, we have used endothelin-B (ET-B and protein kinase-C (PKC inhibitors to evaluate the role of endothelin in ethanol-mediated FL-MTX uptake by using fluoroskan microplate reader. Confocal microscope and fluoroskan studies reveal that cellular absorption of FL-MTX is concentration-dependent. Moreover, ethanol concentration has an impact on FL-MTX uptake. Fluoroskan studies reveal that the ethanol-induced decrease in FL-MTX uptake is reversed by adding the ET-B receptor antagonist (RES-701-1 or PKC-selective inhibitor (BIM. Thus, we can conclude that ethanol may act via ET and ET in turn may act via ET-B receptor and the PKC signaling pathway to impair FL-MTX transport.

  7. Autophagy contributes to gefitinib-induced glioma cell growth inhibition

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Cheng-Yi [Department of Surgery, Fong-Yuan Hospital, Taichung 420, Taiwan (China); Graduate Institute of Pharmaceutical Science and Technology, Central Taiwan University of Science and Technology, Taichung 406, Taiwan (China); Kuan, Yu-Hsiang [Department of Pharmacology, School of Medicine, Chung Shan Medical University, Taichung 402, Taiwan (China); Department of Pharmacy, Chung Shan Medical University Hospital, Taichung 402, Taiwan (China); Ou, Yen-Chuan; Li, Jian-Ri [Division of Urology, Taichung Veterans General Hospital, Taichung 407, Taiwan (China); Wu, Chih-Cheng [Department of Anesthesiology, Taichung Veterans General Hospital, Taichung 407, Taiwan (China); Department of Financial and Computational Mathematics, Providence University, Taichung 433, Taiwan (China); Pan, Pin-Ho [Department of Pediatrics, Tungs’ Taichung MetroHarbor Hospital, Taichung 435, Taiwan (China); Chen, Wen-Ying [Department of Veterinary Medicine, National Chung Hsing University, Taichung 402, Taiwan (China); Huang, Hsuan-Yi [Department of Surgery, Fong-Yuan Hospital, Taichung 420, Taiwan (China); Chen, Chun-Jung, E-mail: cjchen@vghtc.gov.tw [Department of Medical Research, Taichung Veterans General Hospital, Taichung 407, Taiwan (China); Institute of Biomedical Sciences, National Chung Hsing University, Taichung 402, Taiwan (China); Rong Hsing Research Center for Translational Medicine, National Chung Hsing University, Taichung 402, Taiwan (China); Center for General Education, Tunghai University, Taichung 407, Taiwan (China); Department of Nursing, HungKuang University, Taichung 433, Taiwan (China)

    2014-09-10

    Epidermal growth factor receptor tyrosine kinase inhibitors, including gefitinib, have been evaluated in patients with malignant gliomas. However, the molecular mechanisms involved in gefitinib-mediated anticancer effects against glioma are incompletely understood. In the present study, the cytostatic potential of gefitinib was demonstrated by the inhibition of glioma cell growth, long-term clonogenic survival, and xenograft tumor growth. The cytostatic consequences were accompanied by autophagy, as evidenced by monodansylcadaverine staining of acidic vesicle formation, conversion of microtubule-associated protein-1 light chain 3-II (LC3-II), degradation of p62, punctate pattern of GFP-LC3, and conversion of GFP-LC3 to cleaved-GFP. Autophagy inhibitor 3-methyladenosine and chloroquine and genetic silencing of LC3 or Beclin 1 attenuated gefitinib-induced growth inhibition. Gefitinib-induced autophagy was not accompanied by the disruption of the Akt/mammalian target of rapamycin signaling. Instead, the activation of liver kinase-B1/AMP-activated protein kinase (AMPK) signaling correlated well with the induction of autophagy and growth inhibition caused by gefitinib. Silencing of AMPK suppressed gefitinib-induced autophagy and growth inhibition. The crucial role of AMPK activation in inducing glioma autophagy and growth inhibition was further supported by the actions of AMP mimetic AICAR. Gefitinib was shown to be capable of reducing the proliferation of glioma cells, presumably by autophagic mechanisms involving AMPK activation. - Highlights: • Gefitinib causes cytotoxic and cytostatic effect on glioma. • Gefitinib induces autophagy. • Gefitinib causes cytostatic effect through autophagy. • Gefitinib induces autophagy involving AMPK.

  8. Autophagy contributes to gefitinib-induced glioma cell growth inhibition

    International Nuclear Information System (INIS)

    Chang, Cheng-Yi; Kuan, Yu-Hsiang; Ou, Yen-Chuan; Li, Jian-Ri; Wu, Chih-Cheng; Pan, Pin-Ho; Chen, Wen-Ying; Huang, Hsuan-Yi; Chen, Chun-Jung

    2014-01-01

    Epidermal growth factor receptor tyrosine kinase inhibitors, including gefitinib, have been evaluated in patients with malignant gliomas. However, the molecular mechanisms involved in gefitinib-mediated anticancer effects against glioma are incompletely understood. In the present study, the cytostatic potential of gefitinib was demonstrated by the inhibition of glioma cell growth, long-term clonogenic survival, and xenograft tumor growth. The cytostatic consequences were accompanied by autophagy, as evidenced by monodansylcadaverine staining of acidic vesicle formation, conversion of microtubule-associated protein-1 light chain 3-II (LC3-II), degradation of p62, punctate pattern of GFP-LC3, and conversion of GFP-LC3 to cleaved-GFP. Autophagy inhibitor 3-methyladenosine and chloroquine and genetic silencing of LC3 or Beclin 1 attenuated gefitinib-induced growth inhibition. Gefitinib-induced autophagy was not accompanied by the disruption of the Akt/mammalian target of rapamycin signaling. Instead, the activation of liver kinase-B1/AMP-activated protein kinase (AMPK) signaling correlated well with the induction of autophagy and growth inhibition caused by gefitinib. Silencing of AMPK suppressed gefitinib-induced autophagy and growth inhibition. The crucial role of AMPK activation in inducing glioma autophagy and growth inhibition was further supported by the actions of AMP mimetic AICAR. Gefitinib was shown to be capable of reducing the proliferation of glioma cells, presumably by autophagic mechanisms involving AMPK activation. - Highlights: • Gefitinib causes cytotoxic and cytostatic effect on glioma. • Gefitinib induces autophagy. • Gefitinib causes cytostatic effect through autophagy. • Gefitinib induces autophagy involving AMPK

  9. BET bromodomain inhibition promotes neurogenesis while inhibiting gliogenesis in neural progenitor cells

    Directory of Open Access Journals (Sweden)

    Jingjun Li

    2016-09-01

    Full Text Available Neural stem cells and progenitor cells (NPCs are increasingly appreciated to hold great promise for regenerative medicine to treat CNS injuries and neurodegenerative diseases. However, evidence for effective stimulation of neuronal production from endogenous or transplanted NPCs for neuron replacement with small molecules remains limited. To identify novel chemical entities/targets for neurogenesis, we had established a NPC phenotypic screen assay and validated it using known small-molecule neurogenesis inducers. Through screening small molecule libraries with annotated targets, we identified BET bromodomain inhibition as a novel mechanism for enhancing neurogenesis. BET bromodomain proteins, Brd2, Brd3, and Brd4 were found to be downregulated in NPCs upon differentiation, while their levels remain unaltered in proliferating NPCs. Consistent with the pharmacological study using bromodomain selective inhibitor (+-JQ-1, knockdown of each BET protein resulted in an increase in the number of neurons with simultaneous reduction in both astrocytes and oligodendrocytes. Gene expression profiling analysis demonstrated that BET bromodomain inhibition induced a broad but specific transcription program enhancing directed differentiation of NPCs into neurons while suppressing cell cycle progression and gliogenesis. Together, these results highlight a crucial role of BET proteins as epigenetic regulators in NPC development and suggest a therapeutic potential of BET inhibitors in treating brain injuries and neurodegenerative diseases.

  10. The Curcumin Analogue 1,5-Bis(2-hydroxyphenyl-1,4-pentadiene-3-one Induces Apoptosis and Downregulates E6 and E7 Oncogene Expression in HPV16 and HPV18-Infected Cervical Cancer Cells

    Directory of Open Access Journals (Sweden)

    Felicia Paulraj

    2015-06-01

    Full Text Available In an effort to study curcumin analogues as an alternative to improve the therapeutic efficacy of curcumin, we screened the cytotoxic potential of four diarylpentanoids using the HeLa and CaSki cervical cancer cell lines. Determination of their EC50 values indicated relatively higher potency of 1,5-bis(2-hydroxyphenyl-1,4-pentadiene-3-one (MS17, 1.03 ± 0.5 μM; 2.6 ± 0.9 μM and 1,5-bis(4-hydroxy-3-methoxyphenyl-1,4-pentadiene-3-one (MS13, 2.8 ± 0.4; 6.7 ± 2.4 μM in CaSki and HeLa, respectively, with significantly greater growth inhibition at 48 and 72 h of treatment compared to the other analogues or curcumin. Based on cytotoxic and anti-proliferative activity, MS17 was selected for comprehensive apoptotic studies. At 24 h of treatment, fluorescence microscopy detected that MS17-exposed cells exhibited significant morphological changes consistent with apoptosis, corroborated by an increase in nucleosomal enrichment due to DNA fragmentation in HeLa and CaSki cells and activation of caspase-3 activity in CaSki cells. Quantitative real-time PCR also detected significant down-regulation of HPV18- and HPV16-associated E6 and E7 oncogene expression following treatment. The overall data suggests that MS17 treatment has cytotoxic, anti-proliferative and apoptosis-inducing potential in HPV-positive cervical cancer cells. Furthermore, its role in down-regulation of HPV-associated oncogenes responsible for cancer progression merits further investigation into its chemotherapeutic role for cervical cancer.

  11. In vitro cytogenetic testing of an organoselenium compound and its sulfur analogue in cultured rat bone marrow cells

    Directory of Open Access Journals (Sweden)

    Jacob Jacob H

    2004-03-01

    Full Text Available Abstract Background Selenium (Se is a non-metal element, occurring in varying degrees in the environment and it has been found to be a component of several enzymes. Different selenium compounds have been associated with carcinogenicity, toxicity, modification of metal toxicity and prevention of cancer. Organoselenium compounds had substantially greater bioavailability and less toxicity than that of inorganic selenium. From a chemical point of view, Se resembles sulfur (S in many of its properties, thus, Se and S may be considered to be isosteric. The ability of a synthetic organoselenium compound; cyclopenta-dienyldicarbonyl ironselenoterephthalic acid (CSe and its sulfur analogue (CS in the range of 10-8 to 10-5 M, to induce sister-chormatid exchanges (SCE and alter cell division expressed as mitotic index (MI as well as cell survival has been investigated. Methods Rat bone marrow cells were cultured in the presence of CSe and CS in the range of 10-8 to 10-5 M with a total exposure time of 4, 16 or 28 h at 37°C. Fluorescence-plus-Giemsa (FPG technique was used to visualize chromosomes for SCE analysis and MI determination. Trypan blue exclusion technique was used to determine cell viability. Results At the three exposure times, cell survival progressively decreased with increasing concentration, but the effect of either chemical was not significant (ANOVA; P -5 M when either chemical was applied for 16 or 28 h. Furthermore, the mean SCE increased with longer exposure times and, in general, CSe had slightly greater effect on cell survival and caused higher frequencies of SCE than CS. The exception was the 10-8 M treatment. However, both CSe and CS failed to induce 2-fold SCE as that of the negative control and therefore they are not considered as mutagens. Conclusion Both CSe and CS in the range of 10-8 to 10-5 M could not double the SCE rate of the negative control and therefore not considered as mutagens at these experimental conditions.

  12. Effects of the tumor-vasculature-disrupting agent verubulin and two heteroaryl analogues on cancer cells, endothelial cells, and blood vessels.

    Science.gov (United States)

    Mahal, Katharina; Resch, Marcus; Ficner, Ralf; Schobert, Rainer; Biersack, Bernhard; Mueller, Thomas

    2014-04-01

    Two analogues of the discontinued tumor vascular-disrupting agent verubulin (Azixa®, MPC-6827, 1) featuring benzo-1,4-dioxan-6-yl (compound 5 a) and N-methylindol-5-yl (compound 10) residues instead of the para-anisyl group on the 4-(methylamino)-2-methylquinazoline pharmacophore, were prepared and found to exceed the antitumor efficacy of the lead compound. They were antiproliferative with single-digit nanomolar IC50 values against a panel of nine tumor cell lines, while not affecting nonmalignant fibroblasts. Indole 10 surpassed verubulin in seven tumor cell lines including colon, breast, ovarian, and germ cell cancer cell lines. In line with docking studies indicating that compound 10 may bind the colchicine binding site of tubulin more tightly (Ebind =-9.8 kcal mol(-1) ) than verubulin (Ebind =-8.3 kcal mol(-1) ), 10 suppressed the formation of vessel-like tubes in endothelial cells and destroyed the blood vessels in the chorioallantoic membrane of fertilized chicken eggs at nanomolar concentrations. When applied to nude mice bearing a highly vascularized 1411HP germ cell xenograft tumor, compound 10 displayed pronounced vascular-disrupting effects that led to hemorrhages and extensive central necrosis in the tumor. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Cold atmospheric plasma treatment inhibits growth in colorectal cancer cells.

    Science.gov (United States)

    Schneider, Christin; Arndt, Stephanie; Zimmermann, Julia L; Li, Yangfang; Karrer, Sigrid; Bosserhoff, Anja-Katrin

    2018-06-01

    Plasma oncology is a relatively new field of research. Recent developments have indicated that cold atmospheric plasma (CAP) technology is an interesting new therapeutic approach to cancer treatment. In this study, p53 wildtype (LoVo) and human p53 mutated (HT29 and SW480) colorectal cancer cells were treated with the miniFlatPlaSter - a device particularly developed for the treatment of tumor cells - that uses the Surface Micro Discharge (SMD) technology for plasma production in air. The present study analyzed the effects of plasma on colorectal cancer cells in vitro and on normal colon tissue ex vivo. Plasma treatment had strong effects on colon cancer cells, such as inhibition of cell proliferation, induction of cell death, and modulation of p21 expression. In contrast, CAP treatment of murine colon tissue ex vivo for up to 2 min did not show any toxic effect on normal colon cells compared to H2O2 positive control. In summary, these results suggest that the miniFlatPlaSter plasma device is able to kill colorectal cancer cells independent of their p53 mutation status. Thus, this device presents a promising new approach in colon cancer therapy.

  14. Blue light inhibits the growth of B16 melanoma cells

    International Nuclear Information System (INIS)

    Ohara, Masayuki; Katoh, Osamu; Watanabe, Hiromitsu

    2002-01-01

    Although a number of studies have been carried out to examine the biological effects of radiation and ultraviolet radiation (UV), little is known concerning the effects of visible light. In the present study, exposure of B16 melanoma cells to blue light (wavelength 470 nm, irradiance 5.7 mW/cm 2 ) from a light-emitting diode (LED) inhibited cell growth in proportion to the period of exposure, with no increase observed in the number of dead cells. The number of B16 melanoma colonies that formed after exposure to blue light for 20 min was only slightly less than that in non-exposed controls, but the colony size as assessed by the area covered by colonies and cell counts per colony were markedly decreased. The percentages of G0/G1 and G2/M phase cells were markedly increased, with a reduction in S phase cells as determined by flow cytometry after exposure to blue light. Furthermore, analysis of the incorporation of 5-bromo-2'-deoxyuridine (BrdU) into DNA also showed a reduction in the percentage of S phase cells after exposure. These results indicate that blue light exerts cytostatic effects, but not a cytocidal action, on B16 melanoma cells. (author)

  15. Blue light inhibits the growth of B16 melanoma cells

    Energy Technology Data Exchange (ETDEWEB)

    Ohara, Masayuki; Katoh, Osamu; Watanabe, Hiromitsu [Hiroshima Univ. (Japan). Research Inst. for Radiation Biology and Medicine; Kawashima, Yuzo [Otsuka Pharmaceutical Factory, Inc., Naruto, Tokushima (Japan)

    2002-05-01

    Although a number of studies have been carried out to examine the biological effects of radiation and ultraviolet radiation (UV), little is known concerning the effects of visible light. In the present study, exposure of B16 melanoma cells to blue light (wavelength 470 nm, irradiance 5.7 mW/cm{sup 2}) from a light-emitting diode (LED) inhibited cell growth in proportion to the period of exposure, with no increase observed in the number of dead cells. The number of B16 melanoma colonies that formed after exposure to blue light for 20 min was only slightly less than that in non-exposed controls, but the colony size as assessed by the area covered by colonies and cell counts per colony were markedly decreased. The percentages of G0/G1 and G2/M phase cells were markedly increased, with a reduction in S phase cells as determined by flow cytometry after exposure to blue light. Furthermore, analysis of the incorporation of 5-bromo-2'-deoxyuridine (BrdU) into DNA also showed a reduction in the percentage of S phase cells after exposure. These results indicate that blue light exerts cytostatic effects, but not a cytocidal action, on B16 melanoma cells. (author)

  16. Inhibiting DNA-PKCS radiosensitizes human osteosarcoma cells

    International Nuclear Information System (INIS)

    Mamo, Tewodros; Mladek, Ann C.; Shogren, Kris L.; Gustafson, Carl; Gupta, Shiv K.; Riester, Scott M.; Maran, Avudaiappan; Galindo, Mario; Wijnen, Andre J. van; Sarkaria, Jann N.; Yaszemski, Michael J.

    2017-01-01

    Osteosarcoma survival rate has not improved over the past three decades, and the debilitating side effects of the surgical treatment suggest the need for alternative local control approaches. Radiotherapy is largely ineffective in osteosarcoma, indicating a potential role for radiosensitizers. Blocking DNA repair, particularly by inhibiting the catalytic subunit of DNA-dependent protein kinase (DNA-PK CS ), is an attractive option for the radiosensitization of osteosarcoma. In this study, the expression of DNA-PK CS in osteosarcoma tissue specimens and cell lines was examined. Moreover, the small molecule DNA-PK CS inhibitor, KU60648, was investigated as a radiosensitizing strategy for osteosarcoma cells in vitro. DNA-PK CS was consistently expressed in the osteosarcoma tissue specimens and cell lines studied. Additionally, KU60648 effectively sensitized two of those osteosarcoma cell lines (143B cells by 1.5-fold and U2OS cells by 2.5-fold). KU60648 co-treatment also altered cell cycle distribution and enhanced DNA damage. Cell accumulation at the G2/M transition point increased by 55% and 45%, while the percentage of cells with >20 γH2AX foci were enhanced by 59% and 107% for 143B and U2OS cells, respectively. These results indicate that the DNA-PK CS inhibitor, KU60648, is a promising radiosensitizing agent for osteosarcoma. - Highlights: • DNA-PKcs is consistently expressed in human osteosarcoma tissue and cell lines. • The DNA-PKcs inhibitor, KU60648, effectively radiosensitizes osteosarcoma cells. • Combining KU60648 with radiation increases G2/M accumulation and DNA damage.

  17. Effects of PPARα inhibition in head and neck paraganglioma cells.

    Directory of Open Access Journals (Sweden)

    Rosalba Florio

    Full Text Available Head and neck paragangliomas (HNPGLs are rare tumors that may cause important morbidity, because of their tendency to infiltrate the skull base. At present, surgery is the only therapeutic option, but radical removal may be difficult or impossible. Thus, effective targets and molecules for HNPGL treatment need to be identified. However, the lack of cellular models for this rare tumor hampers this task. PPARα receptor activation was reported in several tumors and this receptor appears to be a promising therapeutic target in different malignancies. Considering that the role of PPARα in HNPGLs was never studied before, we analyzed the potential of modulating PPARα in a unique model of HNPGL cells. We observed an intense immunoreactivity for PPARα in HNPGL tumors, suggesting that this receptor has an important role in HNPGL. A pronounced nuclear expression of PPARα was also confirmed in HNPGL-derived cells. The specific PPARα agonist WY14643 had no effect on HNPGL cell viability, whereas the specific PPARα antagonist GW6471 reduced HNPGL cell viability and growth by inducing cell cycle arrest and caspase-dependent apoptosis. GW6471 treatment was associated with a marked decrease of CDK4, cyclin D3 and cyclin B1 protein expression, along with an increased expression of p21 in HNPGL cells. Moreover, GW6471 drastically impaired clonogenic activity of HNPGL cells, with a less marked effect on cell migration. Notably, the effects of GW6471 on HNPGL cells were associated with the inhibition of the PI3K/GSK3β/β-catenin signaling pathway. In conclusion, the PPARα antagonist GW6471 reduces HNPGL cell viability, interfering with cell cycle and inducing apoptosis. The mechanisms affecting HNPGL cell viability involve repression of the PI3K/GSK3β/β-catenin pathway. Therefore, PPARα could represent a novel therapeutic target for HNPGL.

  18. Cellulose synthesis inhibition, cell expansion, and patterns of cell wall deposition in Nitella internodes

    International Nuclear Information System (INIS)

    Richmond, P.A.; Metraux, J.P.

    1984-01-01

    The authors have investigated the pattern of wall deposition and maturation and correlated it with cell expansion and cellulose biosynthesis. The herbicide 2,6-dichlorobenzonitrile (DCB) was found to be a potent inhibitor of cellulose synthesis, but not of cell expansion in Nitella internodal cells. Although cellulose synthesis is inhibited during DCB treatment, matrix substances continue to be synthesized and deposited. The inhibition of cellulose microfibril deposition can be demonstrated by various techniques. These results demonstrate that matrix deposition is by apposition, not by intussusception, and that the previously deposited wall moves progressively outward while stretching and thinning as a result of cell expansion

  19. Indole Alkaloids Inhibiting Neural Stem Cell from Uncaria rhynchophylla.

    Science.gov (United States)

    Wei, Xin; Jiang, Li-Ping; Guo, Ying; Khan, Afsar; Liu, Ya-Ping; Yu, Hao-Fei; Wang, Bei; Ding, Cai-Feng; Zhu, Pei-Feng; Chen, Ying-Ying; Zhao, Yun-Li; Chen, Yong-Bing; Wang, Yi-Fen; Luo, Xiao-Dong

    2017-10-01

    Uncaria rhynchophylla is commonly recognized as a traditional treatment for dizziness, cerebrovascular diseases, and nervous disorders in China. Previously, the neuro-protective activities of the alkaloids from U. rhynchophylla were intensively reported. In current work, three new indole alkaloids (1-3), identified as geissoschizic acid (1), geissoschizic acid N 4 -oxide (2), and 3β-sitsirikine N 4 -oxide (3), as well as 26 known analogues were isolated from U. rhynchophylla. However, in the neural stem cells (NSCs) proliferation assay for all isolated compounds, geissoschizic acid (1), geissoschizic acid N 4 -oxide (2), isocorynoxeine (6), isorhynchophylline (7), (4S)-akuammigine N-oxide (8), and (4S)-rhynchophylline N-oxide (10) showed unexpected inhibitory activities at 10 μM. Unlike previous neuro-protective reports, as a warning or caution, our finding showcased a clue for possible NSCs toxicity and the neural lesions risk of U. rhynchophylla, while the structure-activity relationships of the isolated compounds were discussed also.

  20. The methoxychlor metabolite, HPTE, inhibits rat luteal cell progesterone production.

    Science.gov (United States)

    Akgul, Yucel; Derk, Raymond C; Meighan, Terence; Rao, K Murali Krishna; Murono, Eisuke P

    2011-07-01

    The methoxychlor metabolite, HPTE, was shown to inhibit P450-cholesterol side-chain cleavage (P450scc) activity resulting in decreased progesterone production by cultured ovarian follicular cells in previous studies. It is not known whether HPTE has any effect on progesterone formation by the corpus luteum. Exposure to 100 nM HPTE reduced progesterone production by luteal cells with progressive declines to progesterone formation and P450scc catalytic activity of hCG- or 8 Br-cAMP-stimulated luteal cells. However, HPTE did not alter mRNA and protein levels of P450scc. Compounds acting as estrogen (17 β-estradiol, bisphenol-A or octylphenol), antiestrogen (ICI) or antiandrogen (monobutyl phthalate, flutamide or M-2) added alone to luteal cells did not mimic the action of HPTE on progesterone and P450scc activity. These results suggest that HPTE directly inhibits P450scc catalytic activity resulting in reduced progesterone formation, and this action was not mediated through estrogen or androgen receptors. Published by Elsevier Inc.

  1. IL-17 inhibits chondrogenic differentiation of human mesenchymal stem cells.

    Directory of Open Access Journals (Sweden)

    Masahiro Kondo

    Full Text Available OBJECTIVE: Mesenchymal stem cells (MSCs can differentiate into cells of mesenchymal lineages, such as osteoblasts and chondrocytes. Here we investigated the effects of IL-17, a key cytokine in chronic inflammation, on chondrogenic differentiation of human MSCs. METHODS: Human bone marrow MSCs were pellet cultured in chondrogenic induction medium containing TGF-β3. Chondrogenic differentiation was detected by cartilage matrix accumulation and chondrogenic marker gene expression. RESULTS: Over-expression of cartilage matrix and chondrogenic marker genes was noted in chondrogenic cultures, but was inhibited by IL-17 in a dose-dependent manner. Expression and phosphorylation of SOX9, the master transcription factor for chondrogenesis, were induced within 2 days and phosphorylated SOX9 was stably maintained until day 21. IL-17 did not alter total SOX9 expression, but significantly suppressed SOX9 phosphorylation in a dose-dependent manner. At day 7, IL-17 also suppressed the activity of cAMP-dependent protein kinase A (PKA, which is known to phosphorylate SOX9. H89, a selective PKA inhibitor, also suppressed SOX9 phosphorylation, expression of chondrogenic markers and cartilage matrix, and also decreased chondrogenesis. CONCLUSIONS: IL-17 inhibited chondrogenesis of human MSCs through the suppression of PKA activity and SOX9 phosphorylation. These results suggest that chondrogenic differentiation of MSCs can be inhibited by a mechanism triggered by IL-17 under chronic inflammation.

  2. Neuroglobin Overexpression Inhibits AMPK Signaling and Promotes Cell Anabolism.

    Science.gov (United States)

    Cai, Bin; Li, Wenjun; Mao, XiaoOu; Winters, Ali; Ryou, Myoung-Gwi; Liu, Ran; Greenberg, David A; Wang, Ning; Jin, Kunlin; Yang, Shao-Hua

    2016-03-01

    Neuroglobin (Ngb) is a recently discovered globin with preferential localization to neurons. Growing evidence indicates that Ngb has distinct physiological functions separate from the oxygen storage and transport roles of other globins, such as hemoglobin and myoglobin. We found increased ATP production and decreased glycolysis in Ngb-overexpressing immortalized murine hippocampal cell line (HT-22), in parallel with inhibition of AMP-activated protein kinase (AMPK) signaling and activation of acetyl-CoA carboxylase (ACC). In addition, lipid and glycogen content was increased in Ngb-overexpressing HT-22 cells. AMPK signaling was also inhibited in the brain and heart from Ngb-overexpressing transgenic mice. Although Ngb overexpression did not change glycogen content in whole brain, glycogen synthase was activated in cortical neurons of Ngb-overexpressing mouse brain and Ngb overexpression primary neurons. Moreover, lipid and glycogen content was increased in hearts derived from Ngb-overexpressing mice. These findings suggest that Ngb functions as a metabolic regulator and enhances cellular anabolism through the inhibition of AMPK signaling.

  3. ITE inhibits growth of human pulmonary artery endothelial cells.

    Science.gov (United States)

    Pang, Ling-Pin; Li, Yan; Zou, Qing-Yun; Zhou, Chi; Lei, Wei; Zheng, Jing; Huang, Shi-An

    2017-10-01

    Pulmonary arterial hypertension (PAH), a deadly disorder is associated with excessive growth of human pulmonary artery endothelial (HPAECs) and smooth muscle (HPASMCs) cells. Current therapies primarily aim at promoting vasodilation, which only ameliorates clinical symptoms without a cure. 2-(1'H-indole-3'-carbonyl)-thiazole-4-carboxylic acid methyl ester (ITE) is an endogenous aryl hydrocarbon receptor (AhR) ligand, and mediates many cellular function including cell growth. However, the roles of ITE in human lung endothelial cells remain elusive. Herein, we tested a hypothesis that ITE inhibits growth of human pulmonary artery endothelial cells via AhR. Immunohistochemistry was performed to localize AhR expression in human lung tissues. The crystal violet method and MTT assay were used to determine ITE's effects on growth of HPAECs. The AhR activation in HPAECs was confirmed using Western blotting and RT-qPCR. The role of AhR in ITE-affected proliferation of HPAECs was assessed using siRNA knockdown method followed by the crystal violet method. Immunohistochemistry revealed that AhR was present in human lung tissues, primarily in endothelial and smooth muscle cells of pulmonary veins and arteries, as well as in bronchial and alveolar sac epithelia. We also found that ITE dose- and time-dependently inhibited proliferation of HPAECs with a maximum inhibition of 83% at 20 µM after 6 days of treatment. ITE rapidly decreased AhR protein levels, while it increased mRNA levels of cytochrome P450 (CYP), family 1, member A1 (CYP1A1) and B1 (CYP1B1), indicating activation of the AhR/CYP1A1 and AhR/CYP1B1 pathways in HPAECs. The AhR siRNA significantly suppressed AhR protein expression, whereas it did not significantly alter ITE-inhibited growth of HPAECs. ITE suppresses growth of HPAECs independent of AhR, suggesting that ITE may play an important role in preventing excessive growth of lung endothelial cells.

  4. Hedgehog Pathway Inhibition Radiosensitizes Non-Small Cell Lung Cancers

    Energy Technology Data Exchange (ETDEWEB)

    Zeng, Jing; Aziz, Khaled; Chettiar, Sivarajan T. [Department of Radiation Oncology and Molecular Radiation Sciences, The Johns Hopkins University School of Medicine, Baltimore, Maryland (United States); Aftab, Blake T. [Department of Medical Oncology, The Johns Hopkins University School of Medicine, Baltimore, Maryland (United States); Armour, Michael; Gajula, Rajendra; Gandhi, Nishant; Salih, Tarek; Herman, Joseph M.; Wong, John [Department of Radiation Oncology and Molecular Radiation Sciences, The Johns Hopkins University School of Medicine, Baltimore, Maryland (United States); Rudin, Charles M. [Department of Medical Oncology, The Johns Hopkins University School of Medicine, Baltimore, Maryland (United States); Tran, Phuoc T. [Department of Radiation Oncology and Molecular Radiation Sciences, The Johns Hopkins University School of Medicine, Baltimore, Maryland (United States); Department of Medical Oncology, The Johns Hopkins University School of Medicine, Baltimore, Maryland (United States); Hales, Russell K., E-mail: rhales1@jhmi.edu [Department of Radiation Oncology and Molecular Radiation Sciences, The Johns Hopkins University School of Medicine, Baltimore, Maryland (United States)

    2013-05-01

    Purpose: Despite improvements in chemoradiation, local control remains a major clinical problem in locally advanced non-small cell lung cancer. The Hedgehog pathway has been implicated in tumor recurrence by promoting survival of tumorigenic precursors and through effects on tumor-associated stroma. Whether Hedgehog inhibition can affect radiation efficacy in vivo has not been reported. Methods and Materials: We evaluated the effects of a targeted Hedgehog inhibitor (HhAntag) and radiation on clonogenic survival of human non-small cell lung cancer lines in vitro. Using an A549 cell line xenograft model, we examined tumor growth, proliferation, apoptosis, and gene expression changes after concomitant HhAntag and radiation. In a transgenic mouse model of Kras{sup G12D}-induced and Twist1-induced lung adenocarcinoma, we assessed tumor response to radiation and HhAntag by serial micro-computed tomography (CT) scanning. Results: In 4 human lung cancer lines in vitro, HhAntag showed little or no effect on radiosensitivity. By contrast, in both the human tumor xenograft and murine inducible transgenic models, HhAntag enhanced radiation efficacy and delayed tumor growth. By use of the human xenograft model to differentiate tumor and stromal effects, mouse stromal cells, but not human tumor cells, showed significant and consistent downregulation of Hedgehog pathway gene expression. This was associated with increased tumor cell apoptosis. Conclusions: Targeted Hedgehog pathway inhibition can increase in vivo radiation efficacy in lung cancer preclinical models. This effect is associated with pathway suppression in tumor-associated stroma. These data support clinical testing of Hedgehog inhibitors as a component of multimodality therapy for locally advanced non-small cell lung cancer.

  5. Ginkgo Biloba Extract Kaempferol Inhibits Cell Proliferation and Induces Apoptosis in Pancreatic Cancer Cells

    Science.gov (United States)

    Zhang, Yuqing; Chen, Aaron Y.; Li, Min; Chen, Changyi; Yao, Qizhi

    2010-01-01

    Background Kaempferol is one of the most important constituents in ginkgo flavonoids. Recent studies indicate kaempferol may have anti-tumor activities. The objective in this study was to determine the effect and mechanisms of kaempferol on pancreatic cancer cell proliferation and apoptosis. Materials and Methods Pancreatic cancer cell lines MIA PaCa-2 and Panc-1 were treated with Kampferol, and the inhibitory effects of kaempferol on pancreatic cancer cell proliferation were examined by direct cell counting, 3H-thymidine incorporation and MTS assay. Lactate dehydrogenase (LDH) release from cells was determined as an index of cytotoxicity. Apoptosis was analyzed by TUNEL assay. Results Upon the treatment with 70 μM kaempferol for 4 days, MIA PaCa-2 cell proliferation was significantly inhibited by 79% and 45.7% as determined by direct cell counting and MTS assay, respectively, compared with control cells (Pkaempferol significantly inhibited Panc-1 cell proliferation. Kaempferol treatment also significantly reduced 3H-thymidine incorporation in both MIA PaCa-2 and Panc-1 cells. Combination treatment of low concentrations of kaempferol and 5-fluorouracil (5-FU) showed an additive effect on the inhibition of MIA PaCa-2 cell proliferation. Furthermore, kaempferol had a significantly less cytotoxicity than 5-FU in normal human pancreatic ductal epithelial cells (P=0.029). In both MIA PaCa-2 and Panc-1 cells, apoptotic cell population was increased when treated with kaempferol in a concentration-dependent manner. Conclusions Ginkgo biloba extract kaempferol effectively inhibits pancreatic cancer cell proliferation and induces cancer cell apoptosis, which may sensitize pancreatic tumor cells to chemotherapy. Kaempferol may have clinical applications as adjuvant therapy in the treatment of pancreatic cancer. PMID:18570926

  6. Depletion of Pokemon gene inhibits hepatocellular carcinoma cell growth through inhibition of H-ras.

    Science.gov (United States)

    Zhang, Quan-Le; Tian, De-An; Xu, Xiang-Jiang

    2011-01-01

    Pokemon is a transcription repressor which plays a critical role in cell transformation and malignancy. However, little is known about its effect on the development and progression of hepatocellular carcinoma (HCC). The aim of this study was to investigate the expression of Pokemon in human HCC tissues and the biological behavior of Pokemon in HCC cells in which it is overexpressed. We also explored the expression of potential downstream cofactors of Pokemon. Reverse transcription polymerase chain reaction and Western blot analysis were used to investigate the expression of Pokemon in tissues of 30 HCC patients. We then examined cell proliferation or apoptosis and β-catenin or H-ras expression in Pokemon-depleted HepG(2) cells using DNA vector-based RNA interference technology. Pokemon was markedly expressed in 22/30 (73.3%) HCC tissues, with expression levels higher than in adjacent normal liver tissues (p Pokemon inhibited proliferation of HepG(2) or induced apoptosis. Also, H-ras expression decreased to a large extent. Pokemon exerts its oncogenic activity in the development of HCC by promoting cancer cell growth and reducing apoptosis, and the effect may be mediated by H-ras. Copyright © 2011 S. Karger AG, Basel.

  7. Apoptosis and radiosensitization of Hodgkin cells by proteasome inhibition

    International Nuclear Information System (INIS)

    Pajonk, Frank; Pajonk, Katja; McBride, William H.

    2000-01-01

    Purpose: Malignant cells from Hodgkin's disease have been reported to be defective in regulation of NF-κB activity. Ionizing radiation is known to activate NF-κB, and it has been suggested that this pathway may protect cells from apoptosis following exposure to radiation and other therapeutic agents. Defective NF-κB regulation in Hodgkin cells could therefore dictate the response of this disease to therapy, as well as be responsible for maintaining the malignant phenotype. The purpose of this study was to explore whether NF-κB activity could be modulated in Hodgkin cells and whether it determines the response of these cells to treatment with ionizing radiation and/or dexamethasone. Methods and Materials: Activation of NF-κB in cells is accomplished in large part by degradation of its inhibitor IκB through the 26s proteasome. HD-My-Z Hodgkin cells were treated with the proteasome inhibitor MG-132 or transduced with a dominant negative super-repressor IκBα. Clonogenic survival, apoptosis, proteasome activity, and NF-κB binding activity were monitored in response to ionizing radiation and/or dexamethasone treatment. Results: HD-My-Z Hodgkin cells had modest NF-κB levels but, unlike other cell types, did not decrease their level of constitutively active NF-κB in response to proteasome inhibition with MG-132. In contrast, transduction with a non-phosphorable IκBα construct abolished expression. MG-132 did, however, induce apoptosis in HD-My-Z cells and sensitized them to ionizing radiation. Dexamethasone treatment had no effect on NF-κB activity or clonogenic survival of Hodgkin cells, but protected them from irradiation. Conclusion: We conclude that inhibition of 26s proteasome activity can induce apoptosis in HD-My-Z Hodgkin cells and radiosensitize them, in spite of the fact that their constitutively active NF-κB levels are unaltered. The proteasome may be a promising new therapeutic target for intervention in this disease. In contrast, the use of

  8. Polybrene inhibits human mesenchymal stem cell proliferation during lentiviral transduction.

    Directory of Open Access Journals (Sweden)

    Paul Lin

    Full Text Available Human mesenchymal stem cells (hMSCs can be engineered to express specific genes, either for their use in cell-based therapies or to track them in vivo over long periods of time. To obtain long-term expression of these genes, a lentivirus- or retrovirus-mediated cell transduction is often used. However, given that the efficiency with these viruses is typically low in primary cells, additives such as polybrene are always used for efficient viral transduction. Unfortunately, as presented here, exposure to polybrene alone at commonly used concentratons (1-8 µg/mL negatively impacts hMSC proliferation in a dose-dependent manner as measured by CyQUANT, EdU incorporation, and cell cycle analysis. This inhibition of proliferation was observable in culture even 3 weeks after exposure. Culturing the cells in the presence of FGF-2, a potent mitogen, did not abrogate this negative effect of polybrene. In fact, the normally sharp increase in hMSC proliferation that occurs during the first days of exposure to FGF-2 was absent at 4 µg/mL or higher concentrations of polybrene. Similarly, the effect of stimulating cell proliferation under simulated hypoxic conditions was also decreased when cells were exposed to polybrene, though overall proliferation rates were higher. The negative influence of polybrene was, however, reduced when the cells were exposed to polybrene for a shorter period of time (6 hr vs 24 hr. Thus, careful evaluation should be done when using polybrene to aid in lentiviral transduction of human MSCs or other primary cells, especially when cell number is critical.

  9. Improved Performance in Mammalian Cell Perfusion Cultures by Growth Inhibition.

    Science.gov (United States)

    Wolf, Moritz K F; Closet, Aurélie; Bzowska, Monika; Bielser, Jean-Marc; Souquet, Jonathan; Broly, Hervé; Morbidelli, Massimo

    2018-05-21

    Mammalian cell perfusion cultures represent a promising alternative to the current fed-batch technology for the production of various biopharmaceuticals. Long-term operation at a fixed viable cell density (VCD) requires a viable culture and a constant removal of excessive cells. Product loss in the cell removing bleed stream deteriorates the process yield. In this study, the authors investigate the use of chemical and environmental growth inhibition on culture performance by either adding valeric acid (VA) to the production media or by reducing the culture temperature (33.0 °C) with respect to control conditions (36.5 °C, no VA). Low temperature significantly reduces cellular growth, thus, resulting in lower bleed rates accompanied by a reduced product loss of 11% compared to 26% under control conditions. Additionally, the cell specific productivity of the target protein improves and maintained stable leading to media savings per mass of product. VA shows initially an inhibitory effect on cellular growth. However, cells seemed to adapt to the presence of the inhibitor resulting in a recovery of the cellular growth. Cell cycle and Western blot analyses support the observed results. This work underlines the role of temperature as a key operating variable for the optimization of perfusion cultures. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Murine analogues of etanercept and of F8-IL10 inhibit the progression of collagen-induced arthritis in the mouse.

    Science.gov (United States)

    Doll, Fabia; Schwager, Kathrin; Hemmerle, Teresa; Neri, Dario

    2013-09-27

    Etanercept is a fusion protein consisting of the soluble portion of the p75-tumor necrosis factor receptor (TNFR) and the Fc fragment of human IgG1, which is often used for the treatment of patients with rheumatoid arthritis. F8-IL10 is a human immunocytokine based on the F8 antibody and interleukin-10, which is currently being investigated in rheumatoid arthritis with promising clinical results. We have aimed at expressing murine versions of these two fusion proteins, in order to assess their pharmaceutical performance in the collagen-induced model of rheumatoid arthritis in the mouse. Two fusion proteins (termed muTNFR-Fc and F8-muIL10) were cloned, expressed in chinese hamster ovary (CHO) cells, purified and characterized. Biological activity of muTNFR-Fc was assessed by its ability to inhibit TNF-induced killing of mouse fibroblasts, while F8-muIL10 was characterized in terms of muIL10 activity, of binding affinity to the cognate antigen of F8, the alternatively-spliced EDA domain of fibronectin, by quantitative biodistribution analysis and in vivo imaging. The therapeutic activity of both fusion proteins was investigated in a collagen-induced mouse model of arthritis. Mouse plasma was analyzed for anti-drug antibody formation and cytokine levels were determined by bead-based multiplex technology. The association of F8-IL10 proteins with blood cells was studied in a centrifugation assay with radiolabeled protein. Both fusion proteins exhibited excellent purity and full biological activity in vitro. In addition, F8-muIL10 was able to localize on newly-formed blood vessels in vivo. When used in a murine model of arthritis, the two proteins inhibited arthritis progression. The activity of muTNFR-Fc was tested alone and in combination with F8-huIL10. The chimeric version of F8-IL10 was not better then the fully human fusion protein and showed similar generation of mouse anti-fusion protein antibodies. Incubation studies of F8-muIL10 and F8-huIL10 with blood

  11. Murine macrophage heparanase: inhibition and comparison with metastatic tumor cells

    International Nuclear Information System (INIS)

    Savion, N.; Disatnik, M.H.; Nevo, Z.

    1987-01-01

    Circulating macrophages and metastatic tumor cells can penetrate the vascular endothelium and migrate from the circulatory system to extravascular compartments. Both activated murine macrophages and different metastatic tumor cells attach, invade, and penetrate confluent vascular endothelial cell monolayer in vitro, by degrading heparan sulfate proteoglycans in the subendothelial extracellular matrix. The sensitivity of the enzymes from the various sources degrading the heparan sulfate proteoglycan was challenged and compared by a series of inhibitors. Activated macrophages demonstrate a heparanase with an endoglycosidase activity that cleaves from the [ 35 S]O 4 - -labeled heparan sulfate proteoglycans of the extracellular matrix 10 kDa glycosaminoglycan fragments. The degradation of [ 35 S]O 4 - -labeled extracellular matrix proteoglycans by the macrophages' heparanase is significantly inhibited in the presence of heparan sulfate (10μg/ml), arteparon (10μg/ml), and heparin at a concentration of 3 μg/ml. Degradation of this heparan sulfate proteoglycan is a two-step sequential process involving protease activity followed by heparanase activity. B16-BL6 metastatic melanoma cell heparanase, which is also a cell-associated enzyme, was inhibited by heparin to the same extent as the macrophage haparanase. On the other hand, heparanase of the highly metastatic variant (ESb) of a methylcholanthrene-induced T lymphoma, which is an extracellular enzyme released by the cells to the incubation medium, was more sensitive to heparin and arteparon than the macrophages' heparanase. These results may indicate the potential use of heparin or other glycosaminoglycans as specific and differential inhibitors for the formation in certain cases of blood-borne tumor metastasis

  12. Cortactin Tyrosine Phosphorylation Promotes Its Deacetylation and Inhibits Cell Spreading

    Science.gov (United States)

    Meiler, Eugenia; Nieto-Pelegrín, Elvira; Martinez-Quiles, Narcisa

    2012-01-01

    Background Cortactin is a classical Src kinase substrate that participates in actin cytoskeletal dynamics by activating the Arp2/3 complex and interacting with other regulatory proteins, including FAK. Cortactin has various domains that may contribute to the assembly of different protein platforms to achieve process specificity. Though the protein is known to be regulated by post-translational modifications such as phosphorylation and acetylation, how tyrosine phosphorylation regulates cortactin activity is poorly understood. Since the basal level of tyrosine phosphorylation is low, this question must be studied using stimulated cell cultures, which are physiologically relevant but unreliable and difficult to work with. In fact, their unreliability may be the cause of some contradictory findings about the dynamics of tyrosine phosphorylation of cortactin in different processes. Methodology/Principal Findings In the present study, we try to overcome these problems by using a Functional Interaction Trap (FIT) system, which involves cotransfecting cells with a kinase (Src) and a target protein (cortactin), both of which are fused to complementary leucine-zipper domains. The FIT system allowed us to control precisely the tyrosine phosphorylation of cortactin and explore its relationship with cortactin acetylation. Conclusions/Significance Using this system, we provide definitive evidence that a competition exists between acetylation and tyrosine phosphorylation of cortactin and that phosphorylation inhibits cell spreading. We confirmed the results from the FIT system by examining endogenous cortactin in different cell types. Furthermore, we demonstrate that cell spreading promotes the association of cortactin and FAK and that tyrosine phosphorylation of cortactin disrupts this interaction, which may explain how it inhibits cell spreading. PMID:22479425

  13. Hydroxyurea inhibits parvovirus B19 replication in erythroid progenitor cells.

    Science.gov (United States)

    Bonvicini, Francesca; Bua, Gloria; Conti, Ilaria; Manaresi, Elisabetta; Gallinella, Giorgio

    2017-07-15

    Parvovirus B19 (B19V) infection is restricted to erythroid progenitor cells (EPCs) of the human bone marrow, leading to transient arrest of erythropoiesis and severe complications mainly in subjects with underlying hematological disorders or with immune system deficits. Currently, there are no specific antiviral drugs for B19V treatment, but identification of compounds inhibiting B19V replication can be pursued by a drug repositioning strategy. In this frame, the present study investigates the activity of hydroxyurea (HU), the only disease-modifying therapy approved for sickle cell disease (SCD), towards B19V replication in the two relevant cellular systems, the UT7/EpoS1 cell line and EPCs. Results demonstrate that HU inhibits B19V replication with EC 50 values of 96.2µM and 147.1µM in UT7/EpoS1 and EPCs, respectively, providing experimental evidence of the antiviral activity of HU towards B19V replication, and confirming the efficacy of a drug discovery process by drug repositioning strategy. The antiviral activity occurs in vitro at concentrations lower than those affecting cellular DNA replication and viability, and at levels measured in plasma samples of SCD patients undergoing HU therapy. HU might determine a dual beneficial effect on SCD patients, not only for the treatment of the disease but also towards a virus responsible for severe complications. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. Praziquantel synergistically enhances paclitaxel efficacy to inhibit cancer cell growth.

    Directory of Open Access Journals (Sweden)

    Zhen Hua Wu

    Full Text Available The major challenges we are facing in cancer therapy with paclitaxel (PTX are the drug resistance and severe side effects. Massive efforts have been made to overcome these clinical challenges by combining PTX with other drugs. In this study, we reported the first preclinical data that praziquantel (PZQ, an anti-parasite agent, could greatly enhance the anticancer efficacy of PTX in various cancer cell lines, including PTX-resistant cell lines. Based on the combination index value, we demonstrated that PZQ synergistically enhanced PTX-induced cell growth inhibition. The co-treatment of PZQ and PTX also induced significant mitotic arrest and activated the apoptotic cascade. Moreover, PZQ combined with PTX resulted in a more pronounced inhibition of tumor growth compared with either drug alone in a mouse xenograft model. We tried to investigate the possible mechanisms of this synergistic efficacy induced by PZQ and PTX, and we found that the co-treatment of the two drugs could markedly decrease expression of X-linked inhibitor of apoptosis protein (XIAP, an anti-apoptotic protein. Our data further demonstrated that down-regulation of XIAP was required for the synergistic interaction between PZQ and PTX. Together, this study suggested that the combination of PZQ and PTX may represent a novel and effective anticancer strategy for optimizing PTX therapy.

  15. Synthesis and formulation studies of griseofulvin analogues with improved solubility and metabolic stability

    DEFF Research Database (Denmark)

    Petersen, Asger Bjørn; Andersen, Nikolaj Sten; Konotop, Gleb

    2017-01-01

    Griseofulvin (1) is an important antifungal agent that has recently received attention due to its antiproliferative activity in mammalian cancer cells. Comprehensive SAR studies have led to the identification of 2'-benzyloxy griseofulvin 2, a more potent analogue with low micromolar anticancer...... potency in vitro. Analogue 2 was also shown to retard tumor growth through inhibition of centrosomal clustering in murine xenograft models of colon cancer and multiple myeloma. However, similar to griseofulvin, compound 2 exhibited poor metabolic stability and aqueous solubility. In order to improve...... studies. The 2'-benzylamine analogue 10 proved to be the most promising compound with low μM in vitro anticancer potency, a 200-fold increase in PBS solubility over compound 2, and with improved metabolic stability. Furthermore, this analogue proved compatible with formulations suitable for both oral...

  16. Analogues of luteinizing hormone-releasing hormone containing cytotoxic groups.

    Science.gov (United States)

    Janáky, T; Juhász, A; Bajusz, S; Csernus, V; Srkalovic, G; Bokser, L; Milovanovic, S; Redding, T W; Rékási, Z; Nagy, A

    1992-02-01

    In an attempt to produce better cytotoxic analogues, chemotherapeutic antineoplastic radicals including an alkylating nitrogen mustard derivative of D-phenylalanine (D-melphalan), reactive cyclopropane, anthraquinone derivatives [2-(hydroxymethyl)anthraquinone and the anticancer antibiotic doxorubicin], and an antimetabolite (methotrexate) were coupled to suitably modified agonists and antagonists of luteinizing hormone-releasing hormone (LH-RH). Analogues with D-lysine6 and D-ornithine6 or N epsilon-(2,3-diaminopropionyl)-D-lysine and N delta-(2,3-diaminopropionyl)-D-ornithine were used as carriers for one or two cytotoxic moieties. The enhanced biological activities produced by the incorporation of D amino acids into position 6 of the agonistic analogues were further increased by the attachment of hydrophobic cytotoxic groups, resulting in compounds with 10-50 times higher activity than LH-RH. Most of the monosubstituted agonistic analogues showed high affinities for the membrane receptors of human breast cancer cells, while the receptor binding affinities of peptides containing two cytotoxic side chains were lower. Antagonistic carriers [Ac-D-Nal(2)1,D-Phe(4Cl)2,D-Trp3,Arg5,D-Lys6,D-Ala10] LH-RH [where Nal(2) is 3-(2-naphthyl)alanine], [Ac-D-Nal(2)1,D-Phe(4Cl)2,D-Trp3,Arg5,N epsilon-(2,3-diaminopropionyl)-D-Lys6,D-Ala10]LH-RH, and their D-Pal(3)3 homologs [Pal(3) is 3-(3-pyridyl)alanine] as well as [Ac-D-Nal(2)1,D-Phe(4Cl)2,D-Pal(3)3,Tyr5,N epsilon-(2,3-diamino-propionyl)-D-Lys6,D-Ala10]LH-RH were linked to cytotoxic compounds. The hybrid molecules inhibited ovulation in rats at doses of 10 micrograms and suppressed LH release in vitro. The receptor binding of cytotoxic analogues was decreased compared to the precursor peptides, although analogues with 2-(hydroxymethyl)anthraquinone hemiglutarate had high affinities. All of the cytotoxic analogues tested inhibited [3H]thymidine incorporation into DNA in cultures of human breast and prostate cancer cell lines

  17. N-Pyridineium-2-yl Darrow Red analogue: unique near-infrared lysosome-biomarker for the detection of cancer cells.

    Science.gov (United States)

    He, Dan-Dan; Liu, Wu; Sun, Ru; Fan, Chen; Xu, Yu-Jie; Ge, Jian-Feng

    2015-02-03

    The lysosome-targetable OFF-ON type pH sensor that does not emit at pH = 4.0 is adopted for the selective detection of cancer cells, and the acidity difference of lysosomes in cancer and normal cells is verified. Three pH probes based on Darrow Red derivatives were designed and prepared that were demonstrated to be lysosome-specific biomarkers with inducible emission at 580-850 nm by the comparable in cellular imaging assays using HeLa, KB, and V79 cells. Of these, a pyridineium-2-yl Darrow Red analogue with a pKa of 2.4 was found to be a lysosome tracker for cancer cells, it is a unique pH sensor for the optical identification and distinction of cancer cells from normal cells and has potential application as a fluorescent biomaker of cancer cells in in vitro assays.

  18. Inhibition of canonical WNT signaling attenuates human leiomyoma cell growth

    Science.gov (United States)

    Ono, Masanori; Yin, Ping; Navarro, Antonia; Moravek, Molly B.; Coon, John S.; Druschitz, Stacy A.; Gottardi, Cara J.; Bulun, Serdar E.

    2014-01-01

    Objective Dysregulation of WNT signaling plays a central role in tumor cell growth and progression. Our goal was to assess the effect of three WNT/β-catenin pathway inhibitors, Inhibitor of β-Catenin And TCF4 (ICAT), niclosamide, and XAV939 on the proliferation of primary cultures of human uterine leiomyoma cells. Design Prospective study of human leiomyoma cells obtained from myomectomy or hysterectomy. Setting University research laboratory. Patient(s) Women (n=38) aged 27–53 years undergoing surgery. Intervention(s) Adenoviral ICAT overexpression or treatment with varying concentrations of niclosamide or XAV939. Main Outcome Measure(s) Cell proliferation, cell death, WNT/β-catenin target gene expression or reporter gene regulation, β-catenin levels and cellular localization. Result(s) ICAT, niclosamide, or XAV939 inhibit WNT/β-catenin pathway activation and exert anti-proliferative effects in primary cultures of human leiomyoma cells. Conclusion(s) Three WNT/β-catenin pathway inhibitors specifically block human leiomyoma growth and proliferation, suggesting that the canonical WNT pathway may be a potential therapeutic target for the treatment of uterine leiomyoma. Our findings provide rationale for further preclinical and clinical evaluation of ICAT, niclosamide, and XAV939 as candidate anti-tumor agents for uterine leiomyoma. PMID:24534281

  19. Dextran Sulfate Sodium Inhibits Alanine Synthesis in Caco-2 Cells

    Directory of Open Access Journals (Sweden)

    Carolyn M. Slupsky

    2011-04-01

    Full Text Available To understand and characterize the pathogenic mechanisms of inflammatory bowel disease, dextran sulfate sodium (DSS has been used to induce acute and chronic colitis in animal models by causing intestinal epithelium damage. The mechanism of action of DSS in producing this outcome is not well understood. In an effort to understand how DSS might impact epithelial cell metabolism, we studied the intestinal epithelial cell line Caco-2 incubated with 1% DSS over 56 hours using 1H NMR spectroscopy. We observed no difference in cell viability as compared to control cultures, and an approximately 1.5-fold increase in IL-6 production upon incubation with 1% DSS. The effect on Caco-2 cell metabolism as measured through changes in the concentration of metabolites in the cell supernatant included a three-fold decrease in the concentration of alanine. Given that the concentrations of other amino acids in the cell culture supernatant were not different between treated and control cultures over 56 hours suggest that DSS inhibits alanine synthesis, specifically alanine aminotransferase, without affecting other key metabolic pathways. The importance of alanine aminotransferase in inflammatory bowel disease is discussed.

  20. Resetting cancer stem cell regulatory nodes upon MYC inhibition.

    Science.gov (United States)

    Galardi, Silvia; Savino, Mauro; Scagnoli, Fiorella; Pellegatta, Serena; Pisati, Federica; Zambelli, Federico; Illi, Barbara; Annibali, Daniela; Beji, Sara; Orecchini, Elisa; Alberelli, Maria Adele; Apicella, Clara; Fontanella, Rosaria Anna; Michienzi, Alessandro; Finocchiaro, Gaetano; Farace, Maria Giulia; Pavesi, Giulio; Ciafrè, Silvia Anna; Nasi, Sergio

    2016-12-01

    MYC deregulation is common in human cancer and has a role in sustaining the aggressive cancer stem cell populations. MYC mediates a broad transcriptional response controlling normal biological programmes, but its activity is not clearly understood. We address MYC function in cancer stem cells through the inducible expression of Omomyc-a MYC-derived polypeptide interfering with MYC activity-taking as model the most lethal brain tumour, glioblastoma. Omomyc bridles the key cancer stemlike cell features and affects the tumour microenvironment, inhibiting angiogenesis. This occurs because Omomyc interferes with proper MYC localization and itself associates with the genome, with a preference for sites occupied by MYC This is accompanied by selective repression of master transcription factors for glioblastoma stemlike cell identity such as OLIG2, POU3F2, SOX2, upregulation of effectors of tumour suppression and differentiation such as ID4, MIAT, PTEN, and modulation of the expression of microRNAs that target molecules implicated in glioblastoma growth and invasion such as EGFR and ZEB1. Data support a novel view of MYC as a network stabilizer that strengthens the regulatory nodes of gene expression networks controlling cell phenotype and highlight Omomyc as model molecule for targeting cancer stem cells. © 2016 The Authors.

  1. Antibiotic drug tigecycline inhibited cell proliferation and induced autophagy in gastric cancer cells

    International Nuclear Information System (INIS)

    Tang, Chunling; Yang, Liqun; Jiang, Xiaolan; Xu, Chuan; Wang, Mei; Wang, Qinrui; Zhou, Zhansong; Xiang, Zhonghuai; Cui, Hongjuan

    2014-01-01

    Highlights: • Tigecycline inhibited cell growth and proliferation in human gastric cancer cells. • Tigecycline induced autophagy not apoptosis in human gastric cancer cells. • AMPK/mTOR/p70S6K pathway was activated after tigecycline treatment. • Tigecycline inhibited tumor growth in xenograft model of human gastric cancer cells. - Abstract: Tigecycline acts as a glycylcycline class bacteriostatic agent, and actively resists a series of bacteria, specifically drug fast bacteria. However, accumulating evidence showed that tetracycline and their derivatives such as doxycycline and minocycline have anti-cancer properties, which are out of their broader antimicrobial activity. We found that tigecycline dramatically inhibited gastric cancer cell proliferation and provided an evidence that tigecycline induced autophagy but not apoptosis in human gastric cancer cells. Further experiments demonstrated that AMPK pathway was activated accompanied with the suppression of its downstream targets including mTOR and p70S6K, and ultimately induced cell autophagy and inhibited cell growth. So our data suggested that tigecycline might act as a candidate agent for pre-clinical evaluation in treatment of patients suffering from gastric cancer

  2. Antibiotic drug tigecycline inhibited cell proliferation and induced autophagy in gastric cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Tang, Chunling; Yang, Liqun; Jiang, Xiaolan [State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing 400716 (China); Xu, Chuan [Division of Scientific Research and Training, General Hospital of PLA Chengdu Military Area Command, Chengdu, Sichuan 610083 (China); Wang, Mei; Wang, Qinrui [State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing 400716 (China); Zhou, Zhansong, E-mail: zhouzhans@sina.com [Institute of Urinary Surgery, Southwest Hospital, Third Military Medical University, Chongqing 400038 (China); Xiang, Zhonghuai [State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing 400716 (China); Cui, Hongjuan, E-mail: hcui@swu.edu.cn [State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing 400716 (China)

    2014-03-28

    Highlights: • Tigecycline inhibited cell growth and proliferation in human gastric cancer cells. • Tigecycline induced autophagy not apoptosis in human gastric cancer cells. • AMPK/mTOR/p70S6K pathway was activated after tigecycline treatment. • Tigecycline inhibited tumor growth in xenograft model of human gastric cancer cells. - Abstract: Tigecycline acts as a glycylcycline class bacteriostatic agent, and actively resists a series of bacteria, specifically drug fast bacteria. However, accumulating evidence showed that tetracycline and their derivatives such as doxycycline and minocycline have anti-cancer properties, which are out of their broader antimicrobial activity. We found that tigecycline dramatically inhibited gastric cancer cell proliferation and provided an evidence that tigecycline induced autophagy but not apoptosis in human gastric cancer cells. Further experiments demonstrated that AMPK pathway was activated accompanied with the suppression of its downstream targets including mTOR and p70S6K, and ultimately induced cell autophagy and inhibited cell growth. So our data suggested that tigecycline might act as a candidate agent for pre-clinical evaluation in treatment of patients suffering from gastric cancer.

  3. Inhibition of HSV cell-to-cell spread by lactoferrin and lactoferricin.

    Science.gov (United States)

    Jenssen, Håvard; Sandvik, Kjersti; Andersen, Jeanette H; Hancock, Robert E W; Gutteberg, Tore J

    2008-09-01

    The milk protein lactoferrin (Lf) has multiple functions, including immune stimulation and antiviral activity towards herpes simplex virus 1 and 2 (HSV-1 and HSV-2); antiviral activity has also been reported for the N-terminal pepsin-derived fragment lactoferricin (Lfcin). The anti-HSV mode of action of Lf and Lfcin is assumed to involve, in part, their interaction with the cell surface glycosaminoglycan heparan sulfate, thereby blocking of viral entry. In this study we investigated the ability of human and bovine Lf and Lfcin to inhibit viral cell-to-cell spread as well as the involvement of cell surface glycosaminoglycans during viral cell-to-cell spread. Lf and Lfcin from both human and bovine origin, inhibited cell-to-cell spread of both HSV-1 and HSV-2. Inhibition of cell-to-cell spread by bovine Lfcin involved cell surface chondroitin sulfate. Based on transmission electron microscopy studies, human Lfcin, like bovine Lfcin, was randomly distributed intracellularly, thus differences in their antiviral activity could not be explained by differences in their distribution. In contrast, the cellular localization of iron-saturated (holo)-Lf appeared to differ from that of apo-Lf, indicating that holo- and apo-Lf may exhibit different antiviral mechanisms.

  4. [Inhibition effects of black rice pericarp extracts on cell proliferation of PC-3 cells].

    Science.gov (United States)

    Jiang, Weiwei; Yu, Xudong; Ren, Guofeng

    2013-05-01

    To observe the inhibitive effects of black rice pericarp extracts on cell proliferation of human prostate cancer cell PC-3 and to explore its effecting mechanism. The black rice pericarp extract was used to treat the PC-3 cells. The inhibitory effect of black rice pericarp extract on cells proliferation of PC-3 was tested by MTT method. Cell apoptosis rates and cell cycle were measured by flow cytometric assay (FCM). Western blot was used to study the protein expression levels of p38, p-p38, JNK, p-JNK. A dose-dependent and time-dependent proliferation inhibition of black rice pericarp extract was demonstrated in PC-3. The most prominent experiment condition was inhibitory concentration with 300microg/ml and treated for 72 h. The experiment result of flow cytometry analysis demonstrates that the apoptosis rate of PC-3 cells increased along with the increasing of black rice pericarp extract concentration, and a G1-S cell cycle arrest was induced in a dose-dependent manner. After PC-3 cell was treated with black rice pericarp extract for 72 h, the expressions of p-p38, p-JNK protein increased. Black rice pericarp extract could inhibit proliferation, change the cell cycle distributions and induce apoptosis in human prostatic cancer cell PC-3. Its inhibitory effect may be through promoting activation of the JNK, p38 signaling pathway. These results suggest that black rice pericarp extract maybe has an inhibitory effect on prostatic cancer.

  5. WEHI-3 cells inhibit adipocyte differentiation in 3T3-L1 cells

    Energy Technology Data Exchange (ETDEWEB)

    Lai, Jing [The First Affiliated Hospital, Jinan University, Guangzhou, Guangdong (China); Liu, Gexiu [Institute of Hematology, School of Medicine, Jinan University, Guangzhou, Guangdong (China); Yan, Guoyao [The First Affiliated Hospital, Jinan University, Guangzhou, Guangdong (China); He, Dongmei [Institute of Hematology, School of Medicine, Jinan University, Guangzhou, Guangdong (China); Zhou, Ying [The First Affiliated Hospital, Jinan University, Guangzhou, Guangdong (China); Chen, Shengting, E-mail: shengtingchen@sina.cn [The First Affiliated Hospital, Jinan University, Guangzhou, Guangdong (China)

    2015-06-26

    By investigating the anti-adipogenic effects of WEHI-3 cells – a murine acute myelomonocytic leukemia cell line – we sought to improve the efficiency of hematopoietic stem cell transplantation (HSCT). Analysis of Oil Red O staining and the expression of adipogenic genes, including PPARγ, C/EBPα, FAS and LPL, indicated that WEHI-3 cells significantly inhibited 3T3-L1 mouse preadipocyte cells from differentiating into adipocytes. In vivo, fat vacuoles in mice injected with WEHI-3 cells were also remarkably reduced in the murine bone marrow pimelosis model. Moreover, the key gene in the Rho signaling pathway, ROCKII, and the key gene in the Wnt signaling pathway, β-catenin, were both upregulated compared with the control group. siRNA-mediated knockdown of ROCKII and β-catenin reversed these WEHI-3-mediated anti-adipogenic effects. Taken together, these data suggest that WEHI-3 cells exert anti-adipogenic effects and that both ROCKII and β-catenin are involved in this process. - Highlights: • WEHI-3, an acute myelomonocytic leukemia cell line, inhibited 3T3-L1 preadipocyte from differentiating into adipocyte. • WEHI-3 cells can arrest 3T3-L1 cells in G0/G1 phase by secreting soluble factors and thus inhibit their proliferation. • WEHI-3 cells reduced bone marrow pimelosis in the murine model. • Both ROCKII and β-catenin were involved in the WEHI-3-mediated anti-adipogenic effects.

  6. Bifenthrin inhibits neurite outgrowth in differentiating PC12 cells.

    Science.gov (United States)

    Tran, Van; Hoffman, Natalie; Mofunanaya, Adaobi; Pryor, Stephen C; Ojugbele, Olutosin; McLaughlin, Ashlea; Gibson, Lydia; Bonventre, Josephine A; Flynn, Katherine; Weeks, Benjamin S

    2006-02-01

    Bifenthrin is a third generation member of the synthetic pyrethroid family of insecticides. As a new pesticide within a relatively new class of pesticides, bifenthrin is considered relatively safe. Here, we used the PC12 neuronal cell line to examine the effect of bifenthrin on the formation of neurites and the potential developmental neurotoxicity of this pesticide. PC12 cells were exposed to varying concentrations of technical grade bifenthrin or Ortho Home Defense. Cell viability was determined using the AlmarBlue Toxicity Assay. Nontoxic concentrations of these chemicals were concomitantly with nerve growth factor and neurite outgrowth was assessed. Ortho Home Defense preparation reduced PC12 cell viability by approximately 50% and 70% at dilutions that correlate to bifenthrin concentrations of 10(-5) M and 10(-4) M, respectively. In contrast, technical grade bifenthrin, was not toxic to PC12 cells at 10(-3) M, which was the highest concentration tested that was soluble. At "nontoxic" concentrations of 10(-7) M and 10(-6) M, the Ortho Home Defense inhibited nerve growth factor-mediated neurite outgrowth by 30% and 55% respectively. Furthermore the nontoxic concentrations of technical grade bifenthrin of 10(-6) M and 10(-3) M inhibited neurite outgrowth by approximately 35% and 75% respectively. These data suggest that the toxicity of the Ortho Home Defense preparation was due to the "inert" additives in the preparation and not the bifenthrin itself. Further, these data suggest that, even in the absence of overt toxicity, bifenthrin may have deleterious effects to developing nervous system.

  7. Synthesis and anticancer evaluation of spermatinamine analogues

    KAUST Repository

    Moosa, Basem; Sagar, Sunil; Li, Song; Esau, Luke; Kaur, Mandeep; Khashab, Niveen M.

    2016-01-01

    analogues and their cytotoxic evaluation against three human cancer cell lines i.e. cervix adenocarcinoma (HeLa), breast adenocarcinoma (MCF-7), and prostate carcinoma (DU145). Analogues 12, 14 and 15 were found to be the most potent against one or more cell

  8. Chronic inhibition of tumor cell-derived VEGF enhances the malignant phenotype of colorectal cancer cells

    International Nuclear Information System (INIS)

    Yamagishi, Naoko; Teshima-Kondo, Shigetada; Masuda, Kiyoshi; Nishida, Kensei; Kuwano, Yuki; Dang, Duyen T; Dang, Long H; Nikawa, Takeshi; Rokutan, Kazuhito

    2013-01-01

    Vascular endothelial growth factor-a (VEGF)-targeted therapies have become an important treatment for a number of human malignancies. The VEGF inhibitors are actually effective in several types of cancers, however, the benefits are transiently, and the vast majority of patients who initially respond to the therapies will develop resistance. One of possible mechanisms for the acquired resistance may be the direct effect(s) of VEGF inhibitors on tumor cells expressing VEGF receptors (VEGFR). Thus, we investigated here the direct effect of chronic VEGF inhibition on phenotype changes in human colorectal cancer (CRC) cells. To chronically inhibit cancer cell-derived VEGF, human CRC cell lines (HCT116 and RKO) were chronically exposed (2 months) to an anti-VEGF monoclonal antibody (mAb) or were disrupted the Vegf gene (VEGF-KO). Effects of VEGF family members were blocked by treatment with a VEGF receptor tyrosine kinase inhibitor (VEGFR-TKI). Hypoxia-induced apoptosis under VEGF inhibited conditions was measured by TUNEL assay. Spheroid formation ability was assessed using a 3-D spheroid cell culture system. Chronic inhibition of secreted/extracellular VEGF by an anti-VEGF mAb redundantly increased VEGF family member (PlGF, VEGFR1 and VEGFR2), induced a resistance to hypoxia-induced apoptosis, and increased spheroid formation ability. This apoptotic resistance was partially abrogated by a VEGFR-TKI, which blocked the compensate pathway consisted of VEGF family members, or by knockdown of Vegf mRNA, which inhibited intracellular function(s) of all Vegf gene products. Interestingly, chronic and complete depletion of all Vegf gene products by Vegf gene knockout further augmented these phenotypes in the compensate pathway-independent manner. These accelerated phenotypes were significantly suppressed by knockdown of hypoxia-inducible factor-1α that was up-regulated in the VEGF-KO cell lines. Our findings suggest that chronic inhibition of tumor cell-derived VEGF

  9. Arsenic trioxide inhibits cell proliferation and human papillomavirus oncogene expression in cervical cancer cells

    International Nuclear Information System (INIS)

    Wang, Hongtao; Gao, Peng; Zheng, Jie

    2014-01-01

    Highlights: • As 2 O 3 inhibits growth of cervical cancer cells and expression of HPV oncogenes in these cells. • HPV-negative cervical cancer cells are more sensitive to As 2 O 3 than HPV-positive cervical cancer cells. • HPV-18 positive cervical cancer cells are more sensitive to As 2 O 3 than HPV-16 positive cancer cells. • Down-regulation of HPV oncogenes by As 2 O 3 is partially due to the diminished AP-1 binding. - Abstract: Arsenic trioxide (As 2 O 3 ) has shown therapeutic effects in some leukemias and solid cancers. However, the molecular mechanisms of its anticancer efficacy have not been clearly elucidated, particularly in solid cancers. Our previous data showed that As 2 O 3 induced apoptosis of human papillomavirus (HPV) 16 DNA-immortalized human cervical epithelial cells and cervical cancer cells and inhibited the expression of HPV oncogenes in these cells. In the present study, we systemically examined the effects of As 2 O 3 on five human cervical cancer cell lines and explored the possible molecular mechanisms. MTT assay showed that HPV-negative C33A cells were more sensitive to growth inhibition induced by As 2 O 3 than HPV-positive cervical cancer cells, and HPV 18-positive HeLa and C4-I cells were more sensitive to As 2 O 3 than HPV 16-positive CaSki and SiHa cells. After As 2 O 3 treatment, both mRNA and protein levels of HPV E6 and E7 obviously decreased in all HPV positive cell lines. In contrast, p53 and Rb protein levels increased in all tested cell lines. Transcription factor AP-1 protein expression decreased significantly in HeLa, CaSki and C33A cells with ELISA method. These results suggest that As 2 O 3 is a potential anticancer drug for cervical cancer

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

    DEFF Research Database (Denmark)

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

    2002-01-01

    -Thymidine incorporation assay, respectively. T cells and RPE cells were cultured directly together or in a transwell system for determination of the effect of cell contact. The importance of cell surface molecules was examined by application of a panel of blocking antibodies (CD2, CD18, CD40, CD40L, CD54, CD58......) in addition to use of TCR negative T cell lines. The expression of IL2R-alpha -beta and -gamma chains of activated T cells was analysed by flow cytometry after incubation of T cells alone or with RPE cells. Human RPE cells were found to inhibit the proliferation of activated T cells by a cell contact......-beta and -gamma chain expression within 24 hr after removal from the coculture. It is concluded that the cultured human adult and foetal RPE cells inhibit the proliferation of activated T cells by a process that does not involve apoptosis. It depends on cell contact but the involved surface molecules were...

  11. Downregulation of CCR1 inhibits human hepatocellular carcinoma cell invasion

    International Nuclear Information System (INIS)

    Wu Xiaofeng; Fan Jia; Wang Xiaoying; Zhou Jian; Qiu Shuangjian; Yu Yao; Liu Yinkun; Tang Zhaoyou

    2007-01-01

    CC chemokine receptor 1 (CCR1) has an important role in the recruitment of leukocytes to the site of inflammation. The migration and metastasis of tumor cells shares many similarities with leukocyte trafficking, which is mainly regulated by chemokine receptor-ligand interactions. CCR1 is highly expressed in hepatocellular carcinoma (HCC) cells and tissues with unknown functions. In this study, we silenced CCR1 expression in the human HCC cell line HCCLM3 using artificial microRNA (miRNA)-mediated RNA interference (RNAi) and examined the invasiveness and proliferation of CCR1-silenced HCCLM3 cells and the matrix metalloproteinase (MMP) activity. The miRNA-mediated knockdown expression of CCR1 significantly inhibited the invasive ability of HCCLM3 cells, but had only a minor effect on the cellular proliferation rate. Moreover, CCR1 knockdown significantly reduced the secretion of MMP-2. Together, these findings indicate that CCR1 has an important role in HCCLM3 invasion and that CCR1 might be a new target of HCC treatment

  12. Interim report on intrathoracic radiotherapy of human small-cell lung carcinoma in nude mice with Re-188-RC-160, a radiolabeled somatostatin analogue

    International Nuclear Information System (INIS)

    Zamora, P.O.; Bender, H.; Biersack, H.J.; Knapp, F.F. Jr.

    1995-01-01

    The purpose of this study was to evaluate the therapeutic efficacy of Re-188-RC-160 in experimental models of human small cell lung carcinomas which mimic the clinical presentation. In the experimental model, cells from the human small cell lung carcinoma cell line NCI-H69 cells were inoculated into the thoracic cavity of athymic mice and rats. Subsequently, the biodistribution of Re-188-RC-160 after injection into the pleural cavity, a radiolabeled somatostatin analogue, was monitored as was the effect on the subsequent growth of tumors. The results presented here, and which are a part of a larger series of studies, suggest that Re-188-RC-160 can be effectively used in this animal model to restrict the growth of small cell lung carcinoma in the thoracic cavity

  13. Cholesterol inhibits entotic cell-in-cell formation and actomyosin contraction.

    Science.gov (United States)

    Ruan, Banzhan; Zhang, Bo; Chen, Ang; Yuan, Long; Liang, Jianqing; Wang, Manna; Zhang, Zhengrong; Fan, Jie; Yu, Xiaochen; Zhang, Xin; Niu, Zubiao; Zheng, You; Gu, Songzhi; Liu, Xiaoqing; Du, Hongli; Wang, Jufang; Hu, Xianwen; Gao, Lihua; Chen, Zhaolie; Huang, Hongyan; Wang, Xiaoning; Sun, Qiang

    2018-01-01

    Cell-in-cell structure is prevalent in human cancer, and associated with several specific pathophysiological phenomena. Although cell membrane adhesion molecules were found critical for cell-in-cell formation, the roles of other membrane components, such as lipids, remain to be explored. In this study, we attempted to investigate the effects of cholesterol and phospholipids on the formation of cell-in-cell structures by utilizing liposome as a vector. We found that Lipofectamine-2000, the reagent commonly used for routine transfection, could significantly reduce entotic cell-in-cell formation in a cell-specific manner, which is correlated with suppressed actomyosin contraction as indicated by reduced β-actin expression and myosin light chain phosphorylation. The influence on cell-in-cell formation was likely dictated by specific liposome components as some liposomes affected cell-in-cell formation while some others didn't. Screening on a limited number of lipids, the major components of liposome, identified phosphatidylethanolamine (PE), stearamide (SA), lysophosphatidic acid (LPA) and cholesterol (CHOL) as the inhibitors of cell-in-cell formation. Importantly, cholesterol treatment significantly inhibited myosin light chain phosphorylation, which resembles the effect of Lipofectamine-2000, suggesting cholesterol might be partially responsible for liposomes' effects on cell-in-cell formation. Together, our findings supporting a role of membrane lipids and cholesterol in cell-in-cell formation probably via regulating actomyosin contraction. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. Semicarbazone EGA Inhibits Uptake of Diphtheria Toxin into Human Cells and Protects Cells from Intoxication

    Directory of Open Access Journals (Sweden)

    Leonie Schnell

    2016-07-01

    Full Text Available Diphtheria toxin is a single-chain protein toxin that invades human cells by receptor-mediated endocytosis. In acidic endosomes, its translocation domain inserts into endosomal membranes and facilitates the transport of the catalytic domain (DTA from endosomal lumen into the host cell cytosol. Here, DTA ADP-ribosylates elongation factor 2 inhibits protein synthesis and leads to cell death. The compound 4-bromobenzaldehyde N-(2,6-dimethylphenylsemicarbazone (EGA has been previously shown to protect cells from various bacterial protein toxins which deliver their enzymatic subunits from acidic endosomes to the cytosol, including Bacillus anthracis lethal toxin and the binary clostridial actin ADP-ribosylating toxins C2, iota and Clostridium difficile binary toxin (CDT. Here, we demonstrate that EGA also protects human cells from diphtheria toxin by inhibiting the pH-dependent translocation of DTA across cell membranes. The results suggest that EGA might serve for treatment and/or prevention of the severe disease diphtheria.

  15. Metabolism of the carbocyclic analogue of (E)-5-(2-iodovinyl)-2'-deoxyuridine in herpes simplex virus-infected cells. Incorporation of C-IVDU into DNA

    International Nuclear Information System (INIS)

    De Clercq, E.; Bernaerts, R.; Balzarini, J.; Herdewijn, P.; Verbruggen, A.

    1985-01-01

    The carbocyclic analogues of (E)-5-(2-bromovinyl)-2'-deoxyuridine (BVDU) and (E)-5-(2-iodovinyl)-2'-deoxyuridine (IVDU), in which the sugar moiety is replaced by a cyclopentane ring and which have been designated as C-BVDU and C-IVDU, respectively, are, like their parent compounds BVDU and IVDU, potent and selective inhibitors of herpes simplex virus type 1 (HSV-1) and, to a lesser extent, herpes simplex virus type 2 (HSV-2) replication. The authors have now synthesized the radiolabeled C-IVDU analogue, C-[ 125 I]IVDU, and determined its metabolism by HSV-infected and mock-infected Vero cells. C-[ 125 I]IVDU was effectively phosphorylated by HSV-1-infected cells and, to a lesser extent, HSV-2-infected cells. C-[ 125 I]IVDU was not phosphorylated to an appreciable extent by either mock-infected cells or cells that had been infected with a thymidine kinase-deficient mutant of HSV-1. Furthermore, C-[ 125 I]IVDU was incorporated into both viral and cellular DNA of HSV-1-infected Vero cells. This finding represents the first demonstration of the incorporation of a cyclopentylpyrimidine into DNA

  16. Ketamine inhibits 45Ca influx and catecholamine secretion by inhibiting 22Na influx in cultured bovine adrenal medullary cells

    International Nuclear Information System (INIS)

    Takara, Hiroshi; Wada, Akihiko; Arita, Masahide; Izumi, Futoshi; Sumikawa, Koji

    1986-01-01

    The effects of ketamine, an intravenous anesthetic, on 22 Na influx, 45 Ca influx and catecholamine secretion were investigated in cultured bovine adrenal medullary cells. Ketamine inhibited carbachol-induced 45 Ca influx and catecholamine secretion in a concentration-dependent manner with a similar potency. Ketamine also reduced veratridine-induced 45 Ca influx and catecholamine secretion. The influx of 22 Na caused by carbachol or by veratridine was suppressed by ketamine with a concentration-inhibition curve similar to that of 45 Ca influx and catecholamine secretion. Inhibition by ketamine of the carbachol-induced influx of 22 Na, 45 Ca and secretion of catecholamines was not reversed by the increased concentrations of carbachol. These observations indicate that ketamine, at clinical concentrations, can inhibit nicotinic receptor-associated ionic channels and that the inhibition of Na influx via the receptor-associated ionic channels is responsible for the inhibition of carbachol-induced Ca influx and catecholamine secretion. (Auth.)

  17. Interferon lambda inhibits dengue virus replication in epithelial cells.

    Science.gov (United States)

    Palma-Ocampo, Helen K; Flores-Alonso, Juan C; Vallejo-Ruiz, Verónica; Reyes-Leyva, Julio; Flores-Mendoza, Lilian; Herrera-Camacho, Irma; Rosas-Murrieta, Nora H; Santos-López, Gerardo

    2015-09-28

    In viral disease, infection is controlled at the cellular level by type I interferon (IFN-I), but dengue virus (DENV) has the ability to inhibit this response. Type III interferon, also known as lambda IFN (IFN-III or IFN-λ), is a complementary pathway to the antiviral response by IFN-I. This work analyzed the IFN-λ (IFN-III) mediated antiviral response against DENV serotype 2 (DENV-2) infection. Dengue fever patients were sampled to determine their IFN-λ levels by ELISA. To study the IFN-λ response during DENV infection we selected the epithelial cell line C33-A, and we demonstrated that it is permissive to DENV-2 infection. The effect of IFN-λ on virus replication was determined in these cells, in parallel to the expression of IFN-stimulated genes (ISGs), and Suppressor of Cytokine Signaling (SOCS), genes measured by RT-qPCR. We found increased (~1.8 times) serological IFN-λ in dengue fever patients compared to healthy blood donors. IFN-λ inhibited DENV-2 replication in a dose-dependent manner in vitro. The reduction of viral titer corresponded with increased ISG mRNA levels (MX1 and OAS1), with the highest inhibition occurring at ISG's peak expression. Presence of IFN-negative regulators, SOCS1 and SOCS3, during DENV-2 infection was associated with reduced IFN-λ1 expression. Evidence described here suggests that IFN-λ is a good candidate inhibitor of viral replication in dengue infection. Mechanisms for the cellular and organismal interplay between DENV and IFN- λ need to be further studied as they could provide insights into strategies to treat this disease. Furthermore, we report a novel epithelial model to study dengue infection in vitro.

  18. COBRA1 inhibits AP-1 transcriptional activity in transfected cells

    International Nuclear Information System (INIS)

    Zhong Hongjun; Zhu Jianhua; Zhang Hao; Ding Lihua; Sun Yan; Huang Cuifen; Ye Qinong

    2004-01-01

    Mutations in the breast cancer susceptibility gene (BRCA1) account for a significant proportion of hereditary breast and ovarian cancers. Cofactor of BRCA1 (COBRA1) was isolated as a BRCA1-interacting protein and exhibited a similar chromatin reorganizing activity to that of BRCA1. However, the biological role of COBRA1 remains largely unexplored. Here, we report that ectopic expression of COBRA1 inhibited activator protein 1 (AP-1) transcriptional activity in transfected cells in a dose-dependent manner, whereas reduction of endogenous COBRA1 with a small interfering RNA significantly enhanced AP-1-mediated transcriptional activation. COBRA1 physically interacted with the AP-1 family members, c-Jun and c-Fos, and the middle region of COBRA1 bound to c-Fos. Lack of c-Fos binding site in the COBRA1 completely abolished the COBRA1 inhibition of AP-1 trans-activation. These findings suggest that COBRA1 may directly modulate AP-1 pathway and, therefore, may play important roles in cell proliferation, differentiation, apoptosis, and oncogenesis

  19. Inhibition of Geranylgeranyl Transferase-I Decreases Cell Viability of HTLV-1-Transformed Cells

    Directory of Open Access Journals (Sweden)

    Cynthia A. Pise-Masison

    2011-10-01

    Full Text Available Human T-cell leukemia virus type-1 (HTLV-1 is the etiological agent of adult T-cell leukemia (ATL, an aggressive and highly chemoresistant malignancy. Rho family GTPases regulate multiple signaling pathways in tumorigenesis: cytoskeletal organization, transcription, cell cycle progression, and cell proliferation. Geranylgeranylation of Rho family GTPases is essential for cell membrane localization and activation of these proteins. It is currently unknown whether HTLV-1-transformed cells are preferentially sensitive to geranylgeranylation inhibitors, such as GGTI-298. In this report, we demonstrate that GGTI-298 decreased cell viability and induced G2/M phase accumulation of HTLV-1-transformed cells, independent of p53 reactivation. HTLV-1-LTR transcriptional activity was inhibited and Tax protein levels decreased following treatment with GGTI-298. Furthermore, GGTI-298 decreased activation of NF-κB, a downstream target of Rho family GTPases. These studies suggest that protein geranylgeranylation contributes to dysregulation of cell survival pathways in HTLV-1-transformed cells.

  20. RPF101, a new capsaicin-like analogue, disrupts the microtubule network accompanied by arrest in the G2/M phase, inducing apoptosis and mitotic catastrophe in the MCF-7 breast cancer cells

    International Nuclear Information System (INIS)

    Sá-Júnior, Paulo Luiz de; Pasqualoto, Kerly Fernanda Mesquita; Ferreira, Adilson Kleber; Tavares, Maurício Temotheo; Damião, Mariana Celestina Frojuello Costa Bernstorff; Azevedo, Ricardo Alexandre de; Câmara, Diana Aparecida Dias; Pereira, Alexandre; Madeiro de Souza, Dener; Parise Filho, Roberto

    2013-01-01

    Breast cancer is the world's leading cause of death among women. This situation imposes an urgent development of more selective and less toxic agents. The use of natural molecular fingerprints as sources for new bioactive chemical entities has proven to be a quite promising and efficient method. Capsaicin, which is the primary pungent compound in red peppers, was reported to selectively inhibit the growth of a variety tumor cell lines. Here, we report for the first time a novel synthetic capsaicin-like analogue, RPF101, which presents a high antitumor activity on MCF-7 cell line, inducing arrest of the cell cycle at the G2/M phase through a disruption of the microtubule network. Furthermore, it causes cellular morphologic changes characteristic of apoptosis and a decrease of Δψm. Molecular modeling studies corroborated the biological findings and suggested that RPF101, besides being a more reactive molecule towards its target, may also present a better pharmacokinetic profile than capsaicin. All these findings support the fact that RPF101 is a promising anticancer agent. -- Highlights: ► We report for the first time that RPF101 possesses anticancer properties. ► RPF101 induces apoptosis of human breast cancer cells. ► RPF 101 decreases mitochondrial potential and induces DNA fragmentation.

  1. Dextromethorphan Inhibits Activations and Functions in Dendritic Cells

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    Der-Yuan Chen

    2013-01-01

    Full Text Available Dendritic cells (DCs play an important role in connecting innate and adaptive immunity. Thus, DCs have been regarded as a major target for the development of immunomodulators. In this study, we examined the effect of dextromethorphan (DXM, a common cough suppressant with a high safety profile, on the activation and function of DCs. In the presence of DXM, the LPS-induced expression of the costimulatory molecules in murine bone marrow-derived dendritic cells (BMDCs was significantly suppressed. In addition, DXM treatment reduced the production of reactive oxygen species (ROS, proinflammatory cytokines, and chemokines in maturing BMDCs that were activated by LPS. Therefore, DXM abrogated the ability of LPS-stimulated DCs to induce Ag-specific T-cell activation, as determined by their decreased proliferation and IFN-γ secretion in mixed leukocyte cultures. Moreover, the inhibition of LPS-induced MAPK activation and NF-κB translocation may contribute to the suppressive effect of DXM on BMDCs. Remarkably, DXM decreased the LPS-induced surface expression of CD80, CD83, and HLA-DR and the secretion of IL-6 and IL-12 in human monocyte-derived dendritic cells (MDDCs. These findings provide a new insight into the impact of DXM treatment on DCs and suggest that DXM has the potential to be used in treating DC-related acute and chronic diseases.

  2. ROS accumulation and IGF-IR inhibition contribute to fenofibrate/PPARα -mediated inhibition of Glioma cell motility in vitro

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    Del Valle Luis

    2010-06-01

    Full Text Available Abstract Background Glioblastomas are characterized by rapid cell growth, aggressive CNS infiltration, and are resistant to all known anticancer regimens. Recent studies indicate that fibrates and statins possess anticancer potential. Fenofibrate is a potent agonist of peroxisome proliferator activated receptor alpha (PPARα that can switch energy metabolism from glycolysis to fatty acid β-oxidation, and has low systemic toxicity. Fenofibrate also attenuates IGF-I-mediated cellular responses, which could be relevant in the process of glioblastoma cell dispersal. Methods The effects of fenofibrate on Glioma cell motility, IGF-I receptor (IGF-IR signaling, PPARα activity, reactive oxygen species (ROS metabolism, mitochondrial potential, and ATP production were analyzed in human glioma cell lines. Results Fenofibrate treatment attenuated IGF-I signaling responses and repressed cell motility of LN-229 and T98G Glioma cell lines. In the absence of fenofibrate, specific inhibition of the IGF-IR had only modest effects on Glioma cell motility. Further experiments revealed that PPARα-dependent accumulation of ROS is a strong contributing factor in Glioma cell lines responses to fenofibrate. The ROS scavenger, N-acetyl-cysteine (NAC, restored cell motility, improved mitochondrial potential, and increased ATP levels in fenofibrate treated Glioma cell lines. Conclusions Our results indicate that although fenofibrate-mediated inhibition of the IGF-IR may not be sufficient in counteracting Glioma cell dispersal, PPARα-dependent metabolic switch and the resulting ROS accumulation strongly contribute to the inhibition of these devastating brain tumor cells.

  3. Structural bisphenol analogues differentially target steroidogenesis in murine MA-10 Leydig cells as well as the glucocorticoid receptor

    NARCIS (Netherlands)

    Roelofs, Maarke J|info:eu-repo/dai/nl/357301137; van den Berg, Martin|info:eu-repo/dai/nl/08660466X; Bovee, Toine F H; Piersma, Aldert H|info:eu-repo/dai/nl/071276947; van Duursen, Majorie B|info:eu-repo/dai/nl/181957701

    2015-01-01

    Although much information on the endocrine activity of bisphenol A (BPA) is available, a proper human hazard assessment of analogues that are believed to have a less harmful toxicity profile is lacking. Here the possible effects of BPA, bisphenol F (BPF), bisphenol S (BPS), as well as the brominated

  4. Affinity of vitamin E analogues for the ubiquinone complex II site correlates with their toxicity to cancer cells

    Czech Academy of Sciences Publication Activity Database

    Neužil, Jiří; Černý, Jiří; Dyason, J.C.; Dong, L.-F.; Ralph, S.J.

    2011-01-01

    Roč. 55, č. 10 (2011), s. 1543-1551 ISSN 1613-4125 Institutional research plan: CEZ:AV0Z50520701 Keywords : Vitamin E analogues * mitochondrial complex II * modelling Subject RIV: CE - Biochemistry Impact factor: 4.301, year: 2011

  5. A novel small molecular STAT3 inhibitor, LY5, inhibits cell viability, cell migration, and angiogenesis in medulloblastoma cells.

    Science.gov (United States)

    Xiao, Hui; Bid, Hemant Kumar; Jou, David; Wu, Xiaojuan; Yu, Wenying; Li, Chenglong; Houghton, Peter J; Lin, Jiayuh

    2015-02-06

    Signal transducers and activators of transcription 3 (STAT3) signaling is persistently activated and could contribute to tumorigenesis of medulloblastoma. Numerous studies have demonstrated that inhibition of the persistent STAT3 signaling pathway results in decreased proliferation and increased apoptosis in human cancer cells, indicating that STAT3 is a viable molecular target for cancer therapy. In this study, we investigated a novel non-peptide, cell-permeable small molecule, named LY5, to target STAT3 in medulloblastoma cells. LY5 inhibited persistent STAT3 phosphorylation and induced apoptosis in human medulloblastoma cell lines expressing constitutive STAT3 phosphorylation. The inhibition of STAT3 signaling by LY5 was confirmed by down-regulating the expression of the downstream targets of STAT3, including cyclin D1, bcl-XL, survivin, and micro-RNA-21. LY5 also inhibited the induction of STAT3 phosphorylation by interleukin-6 (IL-6), insulin-like growth factor (IGF)-1, IGF-2, and leukemia inhibitory factor in medulloblastoma cells, but did not inhibit STAT1 and STAT5 phosphorylation stimulated by interferon-γ (IFN-γ) and EGF, respectively. In addition, LY5 blocked the STAT3 nuclear localization induced by IL-6, but did not block STAT1 and STAT5 nuclear translocation mediated by IFN-γ and EGF, respectively. A combination of LY5 with cisplatin or x-ray radiation also showed more potent effects than single treatment alone in the inhibition of cell viability in human medulloblastoma cells. Furthermore, LY5 demonstrated a potent inhibitory activity on cell migration and angiogenesis. Taken together, these findings indicate LY5 inhibits persistent and inducible STAT3 phosphorylation and suggest that LY5 is a promising therapeutic drug candidate for medulloblastoma by inhibiting persistent STAT3 signaling. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

  6. A silyl andrographolide analogue suppresses Wnt/β-catenin signaling pathway in colon cancer.

    Science.gov (United States)

    Reabroi, Somrudee; Chairoungdua, Arthit; Saeeng, Rungnapha; Kasemsuk, Teerapich; Saengsawang, Witchuda; Zhu, Weiming; Piyachaturawat, Pawinee

    2018-05-01

    Hyperactivation of Wnt/β-catenin signaling implicated in oncogenesis of colorectal cancer (CRC) is a potential molecular target for chemotherapy. An andrographolide analogue, 3A.1 (19-tert-butyldiphenylsilyl-8, 17-epoxy andrographolide) has previously been reported to be potently cytotoxic toward cancer cells by unknown molecular mechanisms. The present study explored the anti-cancer activity of analogue 3A.1 on Wnt/β-catenin signaling in colon cancer cells (HT29 cells) which were more sensitive to the others (HCT116 and SW480 cells). Analogue 3A.1 inhibited viability of HT29 cells with IC 50 value of 11.1 ± 1.4 μM at 24 h, which was more potent than that of the parent andrographolide. Analogue 3A.1 also suppressed the proliferation of HT29 cells and induced cell apoptosis in a dose-dependent manner. Its apoptotic activity was accompanied with increased expressions of proteins related to DNA damages; PARP-1 and γ-H2AX. In addition, analogue 3A.1 significantly inhibited T-cell factor and lymphoid enhancer factor (TCF/LEF) promoter activity of Wnt/β-catenin signaling. Accordingly, the expressions of Wnt target genes and β-catenin protein were suppressed. Moreover, analogue 3A.1 increased the activity of GSK-3β kinase, which is a negative regulator responsible for degradation of intracellular β-catenin. This mode of action was further supported by the absence of the effects after treatment with a GSK-3β inhibitor, and over-expression of a mutant β-catenin (S33Y). Our findings reveal, for the first time, an insight into the molecular mechanism of the anti-cancer activity of analogue 3A.1 through the inhibition of Wnt/β-catenin/GSK-3β pathway and provide a therapeutic potential of the andrographolide analogue 3A.1 in CRC treatment. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

  7. In silico and in vitro characterization of anti-amyloidogenic activity of vitamin K3 analogues for Alzheimer's disease.

    Science.gov (United States)

    Huy, Pham Dinh Quoc; Yu, Yao-Chung; Ngo, Son Tung; Thao, Tran Van; Chen, Chin-Piao; Li, Mai Suan; Chen, Yi-Cheng

    2013-04-01

    Aggregation of amyloid-beta (Aβ) has been proposed as the main cause of Alzheimer's disease (AD). Vitamin K deficiency has been linked to the pathogenesis of AD. Therefore, 15 synthesized vitamin K3 (VK3) analogues were studied for their anti-amyloidogenic activity. Biological and spectroscopic assays were used to characterize the effect of VK3 analogues on amyloidogenic properties of Aβ, such as aggregation, free radical formation, and cell viability. Molecular dynamics simulation was used to calculate the binding affinity and mode of VK3 analogue binding to Aβ. Both numerical and experimental results showed that several VK3 analogues, including VK3-6, VK3-8, VK3-9, VK3-10, and VK3-224 could effectively inhibit Aβ aggregation and conformational conversion. The calculated inhibition constants were in the μM range for VK3-10, VK3-6, and VK3-9 which was similar to the IC50 of curcumin. Cell viability assays indicated that VK3-9 could effectively reduce free radicals and had a protective effect on cytotoxicity induced by Aβ. The results clearly demonstrated that VK3 analogues could effectively inhibit Aβ aggregation and protect cells against Aβ induced toxicity. Modified VK3 analogues can possibly be developed as effective anti-amyloidogenic drugs for the treatment of AD. VK3 analogues effectively inhibit Aβ aggregation and are highly potent as anti-amyloidogenic drugs for therapeutic treatment of AD. Copyright © 2012 Elsevier B.V. All rights reserved.

  8. All-trans retinoic acid inhibits craniopharyngioma cell growth: study on an explant cell model.

    Science.gov (United States)

    Li, Qiang; You, Chao; Zhou, Liangxue; Sima, Xiutian; Liu, Zhiyong; Liu, Hao; Xu, Jianguo

    2013-05-01

    The ratio between FABP5 and CRABPII determines cellular response to physiological level of retinoic acid; tumor cells undergo proliferation with high level of FABP5 and apoptosis with high level of CRABPII. We intended to study FABP5 and CRABPII expression in craniopharyngiomas, to establish craniopharyngioma cell model using explants method, and to study the effect of pharmacological dose of retinoic acid on craniopharyngioma cells. Expression of FABP5 and CRABPII in craniopharyngioma tissue from 20 patients was studied using immunohistochemistry. Primary craniopharyngioma cell cultures were established using tissue explants method. Craniopharyngioma cells were treated using various concentrations of all-trans retinoic acid, and cell growth curve, apoptosis, expression of FABP5, CRABPII and NF-κB were assayed in different groups. FABP5/CRABPII ratio was significantly higher in adamatinomatous group than that in papillary group. Cell cultures were established in 19 cases (95 %). Pharmacological level retinoic acid inhibited cell growth and induced cellular apoptosis in dose dependent manner, and apoptosis rate cells treated with 30 μM retinoic acid for 24 h was 43 %. Also, retinoic acid increased CRABPII, and decreased FABP5 and NF-κB expression in craniopharyngioma cells. High FABP5/CRABPII ratio is observed in adamatinomatous craniopharyngioma. Retinoic acid at pharmacological level induced craniopharyngioma cell apoptosis via increasing FABP5/CRABPII ratio and inhibiting NF-κB signaling pathway. Our study demonstrated that all-trans retinoic acid might be a candidate for craniopharyngioma adjuvant chemotherapy in future.

  9. Downregulation of Akt1 Inhibits Anchorage-Independent Cell Growth and Induces Apoptosis in Cancer Cells

    Directory of Open Access Journals (Sweden)

    Xuesong Liu

    2001-01-01

    Full Text Available The serine/threonine kinases, Akti/PKBα, Akt2/PKBβ, and Akt3/PKBγ, play a critical role in preventing cancer cells from undergoing apoptosis. However, the function of individual Akt isoforms in the tumorigenicity of cancer cells is still not well defined. In the current study, we used an AM antisense oligonucleotide (AS to specifically downregulate Akti protein in both cancer and normal cells. Our data indicate that AM AS treatment inhibits the ability of MiaPaCa-2, H460, HCT-15, and HT1080 cells to grow in soft agar. The treatment also induces apoptosis in these cancer cells as demonstrated by FRCS analysis and a caspase activity assay. Conversely, Akti AS treatment has little effect on the cell growth and survival of normal human cells including normal human fibroblast (NHF, fibroblast from muscle (FBM, and mammary gland epithelial 184135 cells. In addition, AM AS specifically sensitizes cancer cells to typical chemotherapeutic agents. Thus, Akti is indispensable for maintaining the tumorigenicity of cancer cells. Inhibition of AM may provide a powerful sensitization agent for chemotherapy specifically in cancer cells.

  10. Murraya koenigii leaf extract inhibits proteasome activity and induces cell death in breast cancer cells

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    Noolu Bindu

    2013-01-01

    Full Text Available Abstract Background Inhibition of the proteolytic activity of 26S proteasome, the protein-degrading machine, is now considered a novel and promising approach for cancer therapy. Interestingly, proteasome inhibitors have been demonstrated to selectively kill cancer cells and also enhance the sensitivity of tumor cells to chemotherapeutic agents. Recently, polyphenols/flavonoids have been reported to inhibit proteasome activity. Murraya koenigii Spreng, a medicinally important herb of Indian origin, has been used for centuries in the Ayurvedic system of medicine. Here we show that Murraya koenigii leaves (curry leaves, a rich source of polyphenols, inhibit the proteolytic activity of the cancer cell proteasome, and cause cell death. Methods Hydro-methanolic extract of curry leaves (CLE was prepared and its total phenolic content [TPC] determined by, the Folin-Ciocalteau’s method. Two human breast carcinoma cell lines: MCF-7 and MDA-MB-231 and a normal human lung fibroblast cell line, WI-38 were used for the studies. Cytotoxicity of the CLE was assessed by the MTT assay. We studied the effect of CLE on growth kinetics using colony formation assay. Growth arrest was assessed by cell cycle analysis and apoptosis by Annexin-V binding using flow cytometry. Inhibition of the endogenous 26S proteasome was studied in intact cells and cell extracts using substrates specific to 20S proteasomal enzymes. Results CLE decreased cell viability and altered the growth kinetics in both the breast cancer cell lines in a dose-dependent manner. It showed a significant arrest of cells in the S phase albeit in cancer cells only. Annexin V binding data suggests that cell death was via the apoptotic pathway in both the cancer cell lines. CLE treatment significantly decreased the activity of the 26S proteasome in the cancer but not normal cells. Conclusions Our study suggests M. koenigii leaves to be a potent source of proteasome inhibitors that lead to cancer cell death

  11. Murraya koenigii leaf extract inhibits proteasome activity and induces cell death in breast cancer cells.

    Science.gov (United States)

    Noolu, Bindu; Ajumeera, Rajanna; Chauhan, Anitha; Nagalla, Balakrishna; Manchala, Raghunath; Ismail, Ayesha

    2013-01-09

    Inhibition of the proteolytic activity of 26S proteasome, the protein-degrading machine, is now considered a novel and promising approach for cancer therapy. Interestingly, proteasome inhibitors have been demonstrated to selectively kill cancer cells and also enhance the sensitivity of tumor cells to chemotherapeutic agents. Recently, polyphenols/flavonoids have been reported to inhibit proteasome activity. Murraya koenigii Spreng, a medicinally important herb of Indian origin, has been used for centuries in the Ayurvedic system of medicine. Here we show that Murraya koenigii leaves (curry leaves), a rich source of polyphenols, inhibit the proteolytic activity of the cancer cell proteasome, and cause cell death. Hydro-methanolic extract of curry leaves (CLE) was prepared and its total phenolic content [TPC] determined by, the Folin-Ciocalteau's method. Two human breast carcinoma cell lines: MCF-7 and MDA-MB-231 and a normal human lung fibroblast cell line, WI-38 were used for the studies. Cytotoxicity of the CLE was assessed by the MTT assay. We studied the effect of CLE on growth kinetics using colony formation assay. Growth arrest was assessed by cell cycle analysis and apoptosis by Annexin-V binding using flow cytometry. Inhibition of the endogenous 26S proteasome was studied in intact cells and cell extracts using substrates specific to 20S proteasomal enzymes. CLE decreased cell viability and altered the growth kinetics in both the breast cancer cell lines in a dose-dependent manner. It showed a significant arrest of cells in the S phase albeit in cancer cells only. Annexin V binding data suggests that cell death was via the apoptotic pathway in both the cancer cell lines. CLE treatment significantly decreased the activity of the 26S proteasome in the cancer but not normal cells. Our study suggests M. koenigii leaves to be a potent source of proteasome inhibitors that lead to cancer cell death. Therefore, identification of active component(s) from the leaf

  12. Aptamers Binding to c-Met Inhibiting Tumor Cell Migration.

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    Birgit Piater

    Full Text Available The human receptor tyrosine kinase c-Met plays an important role in the control of critical cellular processes. Since c-Met is frequently over expressed or deregulated in human malignancies, blocking its activation is of special interest for therapy. In normal conditions, the c-Met receptor is activated by its bivalent ligand hepatocyte growth factor (HGF. Also bivalent antibodies can activate the receptor by cross linking, limiting therapeutic applications. We report the generation of the RNA aptamer CLN64 containing 2'-fluoro pyrimidine modifications by systematic evolution of ligands by exponential enrichment (SELEX. CLN64 and a previously described single-stranded DNA (ssDNA aptamer CLN3 exhibited high specificities and affinities to recombinant and cellular expressed c-Met. Both aptamers effectively inhibited HGF-dependent c-Met activation, signaling and cell migration. We showed that these aptamers did not induce c-Met activation, revealing an advantage over bivalent therapeutic molecules. Both aptamers were shown to bind overlapping epitopes but only CLN3 competed with HGF binding to cMet. In addition to their therapeutic and diagnostic potential, CLN3 and CLN64 aptamers exhibit valuable tools to further understand the structural and functional basis for c-Met activation or inhibition by synthetic ligands and their interplay with HGF binding.

  13. Ginger phytochemicals exhibit synergy to inhibit prostate cancer cell proliferation

    Science.gov (United States)

    Brahmbhatt, Meera; Gundala, Sushma R.; Asif, Ghazia; Shamsi, Shahab A; Aneja, Ritu

    2014-01-01

    Dietary phytochemicals offer non-toxic therapeutic management as well as chemopreventive intervention for slow-growing prostate cancers. However, the limited success of several single-agent clinical trials suggest a paradigm shift that the health benefits of fruits and vegetables are not ascribable due to individual phytochemicals rather may be ascribed to but to synergistic interactions among them. We recently reported growth-inhibiting and apoptosis-inducing properties of ginger extract (GE) in in vitro and in vivo prostate cancer models. Nevertheless, the nature of interactions among the constituent ginger biophenolics, viz. 6-gingerol, 8-gingerol, 10-gingerol, and 6-shogoal, remains elusive. Here we show antiproliferative efficacy of the most-active GE biophenolics as single-agents and in binary combinations, and investigate the nature of their interactions using the Chou-Talalay combination-index (CI) method. Our data demonstrate that binary combinations of ginger phytochemicals synergistically inhibit proliferation of PC-3 cells with CI values ranging from 0.03-0.88. To appreciate synergy among phytochemicals present in GE, the natural abundance of ginger biophenolics was quantitated using LC-UV/MS. Interestingly, combining GE with its constituents (in particular, 6-gingerol) resulted in significant augmentation of GE’s antiproliferative activity. These data generate compelling grounds for further preclinical evaluation of GE alone and in combination with individual ginger biophenols for prostate cancer management. PMID:23441614

  14. Indirubin inhibits cell proliferation, migration, invasion and angiogenesis in tumor-derived endothelial cells

    Directory of Open Access Journals (Sweden)

    Li Z

    2018-05-01

    Full Text Available Zhuohong Li, Chaofu Zhu, Baiping An, Yu Chen, Xiuyun He, Lin Qian, Lan Lan, Shijie Li Department of Oncology, The Affiliated Hospital of Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan, China Purpose: Hepatocellular carcinoma is one of the most predominant malignancies with high fatality rate and its incidence is rising at an alarming rate because of its resistance to radio- and chemotherapy. Indirubin is the major active anti-tumor ingredient of a traditional Chinese herbal medicine. The present study aimed to analyze the effects of indirubin on cell proliferation, migration, invasion, and angiogenesis of tumor-derived endothelial cells (Td-EC. Methods: Td-EC were derived from human umbilical vein endothelial cells (HUVEC by treating HUVEC with the conditioned medium of human liver cancer cell line HepG2. Cell proliferation, migration, invasion, and angiogenesis were assessed by MTT, wound healing, in vitro cell invasion, and in vitro tube formation assay. Results: Td-EC were successfully obtained from HUVEC cultured with 50% culture supernatant from serum-starved HepG2 cells. Indirubin significantly inhibited Td-EC proliferation in a dose- and time-dependent manner. Indirubin also inhibited Td-EC migration, invasion, and angiogenesis. However, indirubin’s effects were weaker on HUVEC than Td-EC. Conclusion: Indirubin significantly inhibited Td-EC proliferation, migration, invasion, and angiogenesis. Keywords: indirubin, Td-EC, proliferation, migration, invasion, angiogenesis

  15. Lichen Secondary Metabolite, Physciosporin, Inhibits Lung Cancer Cell Motility

    Science.gov (United States)

    Yang, Yi; Park, So-Yeon; Nguyen, Thanh Thi; Yu, Young Hyun; Nguyen, Tru Van; Sun, Eun Gene; Udeni, Jayalal; Jeong, Min-Hye; Pereira, Iris; Moon, Cheol; Ha, Hyung-Ho; Kim, Kyung Keun; Hur, Jae-Seoun; Kim, Hangun

    2015-01-01

    Lichens produce various unique chemicals that can be used for pharmaceutical purposes. To screen for novel lichen secondary metabolites showing inhibitory activity against lung cancer cell motility, we tested acetone extracts of 13 lichen samples collected in Chile. Physciosporin, isolated from Pseudocyphellaria coriacea (Hook f. & Taylor) D.J. Galloway & P. James, was identified as an effective compound and showed significant inhibitory activity in migration and invasion assays against human lung cancer cells. Physciosporin treatment reduced both protein and mRNA levels of N-cadherin with concomitant decreases in the levels of epithelial-mesenchymal transition markers such as snail and twist. Physciosporin also suppressed KITENIN (KAI1 C-terminal interacting tetraspanin)-mediated AP-1 activity in both the absence and presence of epidermal growth factor stimulation. Quantitative real-time PCR analysis showed that the expression of the metastasis suppressor gene, KAI1, was increased while that of the metastasis enhancer gene, KITENIN, was dramatically decreased by physciosporin. Particularly, the activity of 3’-untranslated region of KITENIN was decreased by physciosporin. Moreover, Cdc42 and Rac1 activities were decreased by physciosporin. These results demonstrated that the lichen secondary metabolite, physciosporin, inhibits lung cancer cell motility through novel mechanisms of action. PMID:26371759

  16. Inhibition of EV71 by curcumin in intestinal epithelial cells.

    Science.gov (United States)

    Huang, Hsing-I; Chio, Chi-Chong; Lin, Jhao-Yin

    2018-01-01

    EV71 is a positive-sense single-stranded RNA virus that belongs to the Picornaviridae family. EV71 infection may cause various symptoms ranging from hand-foot-and-mouth disease to neurological pathological conditions such as aseptic meningitis, ataxia, and acute transverse myelitis. There is currently no effective treatment or vaccine available. Various compounds have been examined for their ability to restrict EV71 replication. However, most experiments have been performed in rhabdomyosarcoma or Vero cells. Since the gastrointestinal tract is the entry site for this pathogen, we anticipated that orally ingested agents may exert beneficial effects by decreasing virus replication in intestinal epithelial cells. In this study, curcumin (diferuloylmethane, C21H20O6), an active ingredient of turmeric (Curcuma longa Linn) with anti-cancer properties, was investigated for its anti-enterovirus activity. We demonstrate that curcumin treatment inhibits viral translation and increases host cell viability. Curcumin does not exert its anti-EV71 effects by modulating virus attachment or virus internal ribosome entry site (IRES) activity. Furthermore, curcumin-mediated regulation of mitogen-activated protein kinase (MAPK) signaling pathways is not involved. We found that protein kinase C delta (PKCδ) plays a role in virus translation in EV71-infected intestinal epithelial cells and that curcumin treatment decreases the phosphorylation of this enzyme. In addition, we show evidence that curcumin also limits viral translation in differentiated human intestinal epithelial cells. In summary, our data demonstrate the anti-EV71 properties of curcumin, suggesting that ingestion of this phytochemical may protect against enteroviral infections.

  17. Inhibition of EV71 by curcumin in intestinal epithelial cells.

    Directory of Open Access Journals (Sweden)

    Hsing-I Huang

    Full Text Available EV71 is a positive-sense single-stranded RNA virus that belongs to the Picornaviridae family. EV71 infection may cause various symptoms ranging from hand-foot-and-mouth disease to neurological pathological conditions such as aseptic meningitis, ataxia, and acute transverse myelitis. There is currently no effective treatment or vaccine available. Various compounds have been examined for their ability to restrict EV71 replication. However, most experiments have been performed in rhabdomyosarcoma or Vero cells. Since the gastrointestinal tract is the entry site for this pathogen, we anticipated that orally ingested agents may exert beneficial effects by decreasing virus replication in intestinal epithelial cells. In this study, curcumin (diferuloylmethane, C21H20O6, an active ingredient of turmeric (Curcuma longa Linn with anti-cancer properties, was investigated for its anti-enterovirus activity. We demonstrate that curcumin treatment inhibits viral translation and increases host cell viability. Curcumin does not exert its anti-EV71 effects by modulating virus attachment or virus internal ribosome entry site (IRES activity. Furthermore, curcumin-mediated regulation of mitogen-activated protein kinase (MAPK signaling pathways is not involved. We found that protein kinase C delta (PKCδ plays a role in virus translation in EV71-infected intestinal epithelial cells and that curcumin treatment decreases the phosphorylation of this enzyme. In addition, we show evidence that curcumin also limits viral translation in differentiated human intestinal epithelial cells. In summary, our data demonstrate the anti-EV71 properties of curcumin, suggesting that ingestion of this phytochemical may protect against enteroviral infections.

  18. Inhibition of EV71 by curcumin in intestinal epithelial cells

    Science.gov (United States)

    Chio, Chi-Chong; Lin, Jhao-Yin

    2018-01-01

    EV71 is a positive-sense single-stranded RNA virus that belongs to the Picornaviridae family. EV71 infection may cause various symptoms ranging from hand-foot-and-mouth disease to neurological pathological conditions such as aseptic meningitis, ataxia, and acute transverse myelitis. There is currently no effective treatment or vaccine available. Various compounds have been examined for their ability to restrict EV71 replication. However, most experiments have been performed in rhabdomyosarcoma or Vero cells. Since the gastrointestinal tract is the entry site for this pathogen, we anticipated that orally ingested agents may exert beneficial effects by decreasing virus replication in intestinal epithelial cells. In this study, curcumin (diferuloylmethane, C21H20O6), an active ingredient of turmeric (Curcuma longa Linn) with anti-cancer properties, was investigated for its anti-enterovirus activity. We demonstrate that curcumin treatment inhibits viral translation and increases host cell viability. Curcumin does not exert its anti-EV71 effects by modulating virus attachment or virus internal ribosome entry site (IRES) activity. Furthermore, curcumin-mediated regulation of mitogen-activated protein kinase (MAPK) signaling pathways is not involved. We found that protein kinase C delta (PKCδ) plays a role in virus translation in EV71-infected intestinal epithelial cells and that curcumin treatment decreases the phosphorylation of this enzyme. In addition, we show evidence that curcumin also limits viral translation in differentiated human intestinal epithelial cells. In summary, our data demonstrate the anti-EV71 properties of curcumin, suggesting that ingestion of this phytochemical may protect against enteroviral infections. PMID:29370243

  19. Mitochondrial thiol modification by a targeted electrophile inhibits metabolism in breast adenocarcinoma cells by inhibiting enzyme activity and protein levels

    Directory of Open Access Journals (Sweden)

    M. Ryan Smith

    2016-08-01

    Full Text Available Many cancer cells follow an aberrant metabolic program to maintain energy for rapid cell proliferation. Metabolic reprogramming often involves the upregulation of glutaminolysis to generate reducing equivalents for the electron transport chain and amino acids for protein synthesis. Critical enzymes involved in metabolism possess a reactive thiolate group, which can be modified by certain oxidants. In the current study, we show that modification of mitochondrial protein thiols by a model compound, iodobutyl triphenylphosphonium (IBTP, decreased mitochondrial metabolism and ATP in MDA-MB 231 (MB231 breast adenocarcinoma cells up to 6 days after an initial 24 h treatment. Mitochondrial thiol modification also depressed oxygen consumption rates (OCR in a dose-dependent manner to a greater extent than a non-thiol modifying analog, suggesting that thiol reactivity is an important factor in the inhibition of cancer cell metabolism. In non-tumorigenic MCF-10A cells, IBTP also decreased OCR; however the extracellular acidification rate was significantly increased at all but the highest concentration (10 µM of IBTP indicating that thiol modification can have significantly different effects on bioenergetics in tumorigenic versus non-tumorigenic cells. ATP and other adenonucleotide levels were also decreased by thiol modification up to 6 days post-treatment, indicating a decreased overall energetic state in MB231 cells. Cellular proliferation of MB231 cells was also inhibited up to 6 days post-treatment with little change to cell viability. Targeted metabolomic analyses revealed that thiol modification caused depletion of both Krebs cycle and glutaminolysis intermediates. Further experiments revealed that the activity of the Krebs cycle enzyme, aconitase, was attenuated in response to thiol modification. Additionally, the inhibition of glutaminolysis corresponded to decreased glutaminase C (GAC protein levels, although other protein levels were

  20. Lysine demethylase inhibition protects pancreatic β cells from apoptosis and improves β-cell function

    DEFF Research Database (Denmark)

    Backe, Marie Balslev; Andersson, Jan Legaard; Bacos, Karl

    2018-01-01

    ) protects β cells from cytokine-induced apoptosis and reduces type 1 diabetes incidence in animals. We hypothesized that also lysine demethylases (KDMs) regulate β-cell fate in response to inflammatory stress. Expression of the demethylase Kdm6B was upregulated by proinflammatory cytokines suggesting......Transcriptional changes control β-cell survival in response to inflammatory stress. Posttranslational modifications of histone and non-histone transcriptional regulators activate or repress gene transcription, but the link to cell-fate signaling is unclear. Inhibition of lysine deacetylases (KDACs...

  1. Dasatinib inhibits both osteoclast activation and prostate cancer PC-3-cell-induced osteoclast formation.

    Science.gov (United States)

    Araujo, John C; Poblenz, Ann; Corn, Paul; Parikh, Nila U; Starbuck, Michael W; Thompson, Jerry T; Lee, Francis; Logothetis, Christopher J; Darnay, Bryant G

    2009-11-01

    Therapies to target prostate cancer bone metastases have only limited effects. New treatments are focused on the interaction between cancer cells, bone marrow cells and the bone matrix. Osteoclasts play an important role in the development of bone tumors caused by prostate cancer. Since Src kinase has been shown to be necessary for osteoclast function, we hypothesized that dasatinib, a Src family kinase inhibitor, would reduce osteoclast activity and prostate cancer (PC-3) cell-induced osteoclast formation. Dasatinib inhibited RANKL-induced osteoclast differentiation of bone marrow-derived monocytes with an EC(50) of 7.5 nM. PC-3 cells, a human prostate cancer cell line, were able to differentiate RAW 264.7 cells, a murine monocytic cell line, into osteoclasts, and dasatinib inhibited this differentiation. In addition, conditioned medium from PC-3 cell cultures was able to differentiate RAW 264.7 cells into osteoclasts and this too, was inhibited by dasatinib. Even the lowest concentration of dasatinib, 1.25 nmol, inhibited osteoclast differentiation by 29%. Moreover, dasatinib inhibited osteoclast activity by 58% as measured by collagen 1 release. We performed in vitro experiments utilizing the Src family kinase inhibitor dasatinib to target osteoclast activation as a means of inhibiting prostate cancer bone metastases. Dasatinib inhibits osteoclast differentiation of mouse primary bone marrow-derived monocytes and PC-3 cell-induced osteoclast differentiation. Dasatinib also inhibits osteoclast degradation activity. Inhibiting osteoclast differentiation and activity may be an effective targeted therapy in patients with prostate cancer bone metastases.

  2. Differences in antiproliferative effect of STAT3 inhibition in HCC cells with versus without HBV expression

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Yun; Zhou, Lin; Xie, Haiyang; Wang, Weilin [Division of Hepatobiliary and Pancreatic Surgery, Department of Surgery, First Affiliated Hospital, School of Medicine, Zhejiang University, Qingchun Road 79, Hangzhou, Zhejiang 310003 (China); Key Laboratory of Combined Multi-organ Transplantation of Ministry of Public Health, Qingchun Road 79, Hangzhou, Zhejiang 310003 (China); Zheng, Shusen, E-mail: shusenzheng@zju.edu.cn [Division of Hepatobiliary and Pancreatic Surgery, Department of Surgery, First Affiliated Hospital, School of Medicine, Zhejiang University, Qingchun Road 79, Hangzhou, Zhejiang 310003 (China); Key Laboratory of Combined Multi-organ Transplantation of Ministry of Public Health, Qingchun Road 79, Hangzhou, Zhejiang 310003 (China)

    2015-06-05

    Chronic infection with hepatitis B virus (HBV) plays an important role in the etiology of hepatocellular carcinoma (HCC). Signal transducer and activator of transcription 3 (STAT3) inactivation could inhibit the tumor growth of HCC. In this study, differential antiproliferative effect of STAT3 inhibition was observed with HBV-related HCC cells being more resistant than non-HBV-related HCC cells. Resistance of HBV-related HCC cells to STAT3 inhibition was positively correlated to the expression of HBV. Enhanced ERK activation after STAT3 blockade was detected in HBV-related HCC cells but not in non-HBV-related HCC cells. Combined ERK and STAT3 inhibition eliminates the discrepancy between the two types of HCC cells. Moderate reduced HBV expression was found after STAT3 inhibition. These findings disclose a discrepancy in cellular response to STAT3 inhibition between non-HBV-related and HBV-related HCC cells and underscore the complexity of antiproliferative effect of STAT3 inactivation in HBV-related HCC cells. - Highlights: • HBV endows HCC cells with resistance to STAT3 inactivation on proliferation. • Abnormal ERK activation after STAT3 inhibition in HBV-related HCC cells. • Combined ERK and STAT3 inhibition eliminates the discrepancy. • STAT3 inhibition moderately reduces HBV expression.

  3. Differences in antiproliferative effect of STAT3 inhibition in HCC cells with versus without HBV expression

    International Nuclear Information System (INIS)

    Hong, Yun; Zhou, Lin; Xie, Haiyang; Wang, Weilin; Zheng, Shusen

    2015-01-01

    Chronic infection with hepatitis B virus (HBV) plays an important role in the etiology of hepatocellular carcinoma (HCC). Signal transducer and activator of transcription 3 (STAT3) inactivation could inhibit the tumor growth of HCC. In this study, differential antiproliferative effect of STAT3 inhibition was observed with HBV-related HCC cells being more resistant than non-HBV-related HCC cells. Resistance of HBV-related HCC cells to STAT3 inhibition was positively correlated to the expression of HBV. Enhanced ERK activation after STAT3 blockade was detected in HBV-related HCC cells but not in non-HBV-related HCC cells. Combined ERK and STAT3 inhibition eliminates the discrepancy between the two types of HCC cells. Moderate reduced HBV expression was found after STAT3 inhibition. These findings disclose a discrepancy in cellular response to STAT3 inhibition between non-HBV-related and HBV-related HCC cells and underscore the complexity of antiproliferative effect of STAT3 inactivation in HBV-related HCC cells. - Highlights: • HBV endows HCC cells with resistance to STAT3 inactivation on proliferation. • Abnormal ERK activation after STAT3 inhibition in HBV-related HCC cells. • Combined ERK and STAT3 inhibition eliminates the discrepancy. • STAT3 inhibition moderately reduces HBV expression

  4. The Potent Humanin Analogue (HNG) Protects Germ Cells and Leucocytes While Enhancing Chemotherapy-Induced Suppression of Cancer Metastases in Male Mice.

    Science.gov (United States)

    Lue, YanHe; Swerdloff, Ronald; Wan, Junxiang; Xiao, Jialin; French, Samuel; Atienza, Vince; Canela, Victor; Bruhn, Kevin W; Stone, Brian; Jia, Yue; Cohen, Pinchas; Wang, Christina

    2015-12-01

    Humanin is a peptide that is cytoprotective against stresses in many cell types. We investigated whether a potent humanin analogue S14G-humanin (HNG) would protect against chemotherapy-induced damage to normal cells without interfering with the chemotherapy-induced suppression of cancer cells. Young adult male mice were inoculated iv with murine melanoma cells. After 1 week, cancer-bearing mice were randomized to receive either: no treatment, daily ip injection of HNG, a single ip injection of cyclophosphamide (CP), or CP+HNG and killed at the end of 3 weeks. HNG rescued the CP-induced suppression of leucocytes and protected germ cell from CP-induced apoptosis. Lung metastases were suppressed by HNG or CP alone, and further suppressed by CP+HNG treatment. Plasma IGF-1 levels were suppressed by HNG with or without CP treatment. To investigate whether HNG maintains its protective effects on spermatogonial stem cells, sperm output, and peripheral leucocytes after repeated doses of CP, normal adult male mice received: no treatment, daily sc injection of HNG, 6 ip injections of CP at 5-day intervals, and the same regimens of CP+HNG and killed at the end of 4 weeks of treatment. Cauda epididymal sperm counts were elevated by HNG and suppressed by CP. HNG rescued the CP-induced suppression of spermatogonial stem cells, sperm count and peripheral leucocytes. We conclude that HNG 1) protects CP-induced loss of male germ cells and leucocytes, 2) enhances CP-induced suppression of cancer metastases, and 3) acts as a caloric-restriction mimetic by suppressing IGF-1 levels. Our findings suggest that humanin analogues may be promising adjuvants to chemotherapy.

  5. Vitisin A inhibits adipocyte differentiation through cell cycle arrest in 3T3-L1 cells

    International Nuclear Information System (INIS)

    Kim, Soon-hee; Park, Hee-Sook; Lee, Myoung-su; Cho, Yong-Jin; Kim, Young-Sup; Hwang, Jin-Taek; Sung, Mi Jeong; Kim, Myung Sunny; Kwon, Dae Young

    2008-01-01

    Inhibition of adipocyte differentiation is one approach among the anti-obesity strategies. This study demonstrates that vitisin A, a resveratrol tetramer, inhibits adipocyte differentiation most effectively of 18 stilbenes tested. Fat accumulation and PPARγ expression were decreased by vitisin A in a dose-dependent manner. Vitisin A significantly inhibited preadipocyte proliferation and consequent differentiation within the first 2 days of treatment, indicating that the anti-adipogenic effect of vitisin A was derived from anti-proliferation. Based on cell cycle analysis, vitisin A blocked the cell cycle at the G1-S phase transition, causing cells to remain in the preadipocyte state. Vitisin A increased p21 expression, while the Rb phosphorylation level was reduced. Therefore, vitisin A seems to induce G1 arrest through p21- and consequent Rb-dependent suppression of transcription. On the other hand, ERK and Akt signaling pathways were not involved in the anti-mitotic regulation by vitisin A. Taken together, these results suggest that vitisin A inhibits adipocyte differentiation through preadipocyte cell cycle arrest

  6. Spiromastixones Inhibit Foam Cell Formation via Regulation of Cholesterol Efflux and Uptake in RAW264.7 Macrophages

    Directory of Open Access Journals (Sweden)

    Chongming Wu

    2015-10-01

    Full Text Available Bioassay-guided evaluation shows that a deep sea-derived fungus, Spiromastix sp. MCCC 3A00308, possesses lipid-lowering activity. Chromatographic separation of a culture broth resulted in the isolation of 15 known depsidone-based analogues, labeled spiromastixones A–O (1–15. Each of these compounds was tested for its ability to inhibit oxidized low-density lipoprotein (oxLDL-induced foam cell formation in RAW264.7 macrophages. Spiromastixones 6–8 and 12–14 significantly decreased oxLDL-induced lipid over-accumulation, reduced cell surface area, and reduced intracellular cholesterol concentration. Of these compounds, spiromastixones 6 and 14 exerted the strongest inhibitory effects. Spiromastixones 6 and 14 dramatically inhibited cholesterol uptake and stimulated cholesterol efflux to apolipoprotein A1 (ApoA1 and high-density lipoprotein (HDL in RAW264.7 macrophages. Mechanistic investigation indicated that spiromastixones 6, 7, 12 and 14 significantly up-regulated the mRNA levels of ATP-binding cassette sub-family A1 (ABCA1 and down-regulated those of scavenger receptor CD36, while the transcription of ATP-binding cassette sub-family A1 (ABCG1 and proliferator-activated receptor gamma (PPARγ were selectively up-regulated by 6 and 14. A transactivation reporter assay revealed that spiromastixones 6 and 14 remarkably enhanced the transcriptional activity of PPARγ. These results suggest that spiromastixones inhibit foam cell formation through upregulation of PPARγ and ABCA1/G1 and downregulation of CD36, indicating that spiromastixones 6 and 14 are promising lead compounds for further development as anti-atherogenic agents.

  7. The anti-epileptic drug valproic acid (VPA inhibits steroidogenesis in bovine theca and granulosa cells in vitro.

    Directory of Open Access Journals (Sweden)

    Claire Glister

    Full Text Available Valproic acid (VPA is used widely to treat epilepsy and bipolar disorder. Women undergoing VPA treatment reportedly have an increased incidence of polycystic ovarian syndrome (PCOS-like symptoms including hyperandrogenism and oligo- or amenorrhoea. To investigate potential direct effects of VPA on ovarian steroidogenesis we used primary bovine theca (TC and granulosa (GC cells maintained under conditions that preserve their 'follicular' phenotype. Effects of VPA (7.8-500 µg/ml on TC were tested with/without LH. Effects of VPA on GC were tested with/without FSH or IGF analogue. VPA reduced (P99% decrease; P<0.0001 with lesser effects on LHR, STAR, CYP11A1 and HSD3B1 mRNA (<90% decrease; P<0.05. VPA only reduced TC progesterone secretion induced by the highest (luteinizing LH dose tested; TC number was unaffected by VPA. At higher concentrations (125-500 µg/ml VPA inhibited basal, FSH- and IGF-stimulated estradiol secretion (P<0.0001 by GC without affecting progesterone secretion or cell number. VPA reversed FSH-induced upregulation of CYP19A1 and HSD17B1 mRNA abundance (P<0.001. The potent histone deacetylase (HDAC inhibitors trichostatin A and scriptaid also suppressed TC androstenedione secretion and granulosal cell oestrogen secretion suggesting that the action of VPA reflects its HDAC inhibitory properties. In conclusion, these findings refute the hypothesis that VPA has a direct stimulatory action on TC androgen output. On the contrary, VPA inhibits both LH-dependent androgen production and FSH/IGF-dependent estradiol production in this in vitro bovine model, likely by inhibition of HDAC.

  8. Nicotine inhibits potassium currents in Aplysia bag cell neurons

    Science.gov (United States)

    White, Sean H.; Sturgeon, Raymond M.

    2016-01-01

    Acetylcholine and the archetypal cholinergic agonist, nicotine, are typically associated with the opening of ionotropic receptors. In the bag cell neurons, which govern the reproductive behavior of the marine snail, Aplysia californica, there are two cholinergic responses: a relatively large acetylcholine-induced current and a relatively small nicotine-induced current. Both currents are readily apparent at resting membrane potential and result from the opening of distinct ionotropic receptors. We now report a separate current response elicited by applying nicotine to cultured bag cell neurons under whole cell voltage-clamp. This current was ostensibly inward, best resolved at depolarized voltages, presented a noncooperative dose-response with a half-maximal concentration near 1.5 mM, and associated with a decrease in membrane conductance. The unique nicotine-evoked response was not altered by intracellular perfusion with the G protein blocker GDPβS or exposure to classical nicotinic antagonists but was occluded by replacing intracellular K+ with Cs+. Consistent with an underlying mechanism of direct inhibition of one or more K+ channels, nicotine was found to rapidly reduce the fast-inactivating A-type K+ current as well as both components of the delayed-rectifier K+ current. Finally, nicotine increased bag cell neuron excitability, which manifested as reduction in spike threshold, greater action potential height and width, and markedly more spiking to continuous depolarizing current injection. In contrast to conventional transient activation of nicotinic ionotropic receptors, block of K+ channels could represent a nonstandard means for nicotine to profoundly alter the electrical properties of neurons over prolonged periods of time. PMID:26864763

  9. Inhibition of Zoledronic Acid on Cell Proliferation and Invasion of Lung Cancer Cell Line 95D

    Directory of Open Access Journals (Sweden)

    Mingming LI

    2009-03-01

    Full Text Available Background and objective Abnormal proliferation and metastasis is the basic characteristic of malignant tumors. The aim of this work is to explore the effects of zoledronic acid on cell proliferation and invasion in lung cancer cell line 95D. Methods The effect of zoledrnic acid (ZOL on proliferation of lung cancer cell line 95D was detected by MTT. The expression of proliferation and invasion-relation genes and proteins were detected by Western blot, RT-PCR and immunofluorescence. Changes of invasion of lung cancer cell numbers were measured by polycarbonates coated with Matrigel. Results ZOL could inhibit the proliferation of lung cancer cell line 95D in vitro in a time-dependant and a dose-dependant manner. With time extending after ZOL treated, the mRNA expresion of VEGF, MMP9, MMP2 and protein expression of VEGF, MMP9, ERK1/ ERK2 were decreased. The results of Tanswell invasion showed the numbers of invasive cells were significantly reduced in 95D cells treated with ZOL 4 d and 6 d later. Conclusion ZOL could inhibit cell proliferation and invasion of lung cancer cell line 95D.

  10. Mesenchymal Stem Cells from Patients with Rheumatoid Arthritis Display Impaired Function in Inhibiting Th17 Cells

    Directory of Open Access Journals (Sweden)

    Yue Sun

    2015-01-01

    Full Text Available Mesenchymal stem cells (MSCs possess multipotent and immunomodulatory properties and are suggested to be involved in the pathogenesis of immune-related diseases. This study explored the function of bone marrow MSCs from rheumatoid arthritis (RA patients, focusing on immunomodulatory effects. RA MSCs showed decreased proliferative activity and aberrant migration capacity. No significant differences were observed in cytokine profiles between RA and control MSCs. The effects of RA MSCs on proliferation of peripheral blood mononuclear cells (PBMCs and distribution of specific CD4+ T cell subtypes (Th17, Treg, and Tfh cells were investigated. RA MSCs appeared to be indistinguishable from controls in suppressing PBMC proliferation, decreasing the proportion of Tfh cells, and inducing the polarization of Treg cells. However, the capacity to inhibit Th17 cell polarization was impaired in RA MSCs, which was related to the low expression of CCL2 in RA MSCs after coculture with CD4+ T cells. These findings indicated that RA MSCs display defects in several important biological activities, especially the capacity to inhibit Th17 cell polarization. These functionally impaired MSCs may contribute to the development of RA disease.

  11. Solena amplexicaulis induces cell cycle arrest, apoptosis and inhibits angiogenesis in hepatocarcinoma cells and HUVECs.

    Science.gov (United States)

    Ren, Jie; Xu, Yuan Yuan; Jiang, He Fei; Yang, Meng; Huang, Qian Hui; Yang, Jie; Hu, Kun; Wei, Kun

    2014-01-01

    Solena amplexicaulis (Lam.) Gandhi (SA) has been used as a traditional medicine for the treatment of dysentery, multiple abscess, gastralgia, urethritis, and eczema in the minority area of China. This study was aimed to examine the cell proliferation inhibitory activity of the SA extract (SACE) and its mechanism of action in human hepatoma cell line (HepG2) and evaluate its anti-angiogenesis activity in human umbilical vein endothelial cell line (HUVEC). SACE could inhibit the growth of HepG2 cells in a dose- and time-dependent manner. FCM analysis showed that SACE could induce G2/M phase arrest, cell apoptosis, the mitochondrial membrane potential loss (ΔΨm) and increase the production of intracellular ROS of HepG2 cells. After treatment with SACE, topical morphological changes of apoptotic body formation, obvious increase of apoptosis-related protein expressions, such as Bax, cytochrome c, caspase-3, PARP-1, and decrease of Bcl-2, procaspase-9 protein expressions were observed at the same time. Moreover, SACE caused the significant inhibition of endothelial cell migration and tube formation in HUVEC cells. The results suggested that SACE could act as an angiogenesis inhibitor and induce cell apoptosis via a caspase-dependent mitochondrial pathway. Therefore, SACE could be a potent candidate for the prevention and treatment of liver cancer.

  12. D-Glucosamine inhibits proliferation of human cancer cells through inhibition of p70S6K

    International Nuclear Information System (INIS)

    Oh, Hyun-Ji; Lee, Jason S.; Song, Dae-Kyu; Shin, Dong-Hoon; Jang, Byeong-Churl; Suh, Seong-Il; Park, Jong-Wook; Suh, Min-Ho; Baek, Won-Ki

    2007-01-01

    Although D-glucosamine has been reported as an inhibitor of tumor growth both in vivo and in vitro, the mechanism for the anticancer effect of D-glucosamine is still unclear. Since there are several reports suggesting D-glucosamine inhibits protein synthesis, we examined whether D-glucosamine affects p70S6 K activity, an important signaling molecule involved in protein translation. In the present study, we found D-glucosamine inhibited the activity of p70S6K and the proliferation of DU145 prostate cancer cells and MDA-MB-231 breast cancer cells. D-Glucosamine decreased phosphorylation of p70S6K, and its downstream substrates RPS6, and eIF-4B, but not mTOR and 4EBP1 in DU145 cells, suggesting that D-glucosamine induced inhibition of p70S6K is not through the inhibition of mTOR. In addition, D-glucosamine enhanced the growth inhibitory effects of rapamycin, a specific inhibitor of mTOR. These findings suggest that D-glucosamine can inhibit growth of cancer cells through dephosphorylation of p70S6K

  13. Mitochondria-targeted vitamin E analogs inhibit breast cancer cell energy metabolism and promote cell death

    International Nuclear Information System (INIS)

    Cheng, Gang; Zielonka, Jacek; McAllister, Donna M; Mackinnon, A Craig Jr; Joseph, Joy; Dwinell, Michael B; Kalyanaraman, Balaraman

    2013-01-01

    Recent research has revealed that targeting mitochondrial bioenergetic metabolism is a promising chemotherapeutic strategy. Key to successful implementation of this chemotherapeutic strategy is the use of new and improved mitochondria-targeted cationic agents that selectively inhibit energy metabolism in breast cancer cells, while exerting little or no long-term cytotoxic effect in normal cells. In this study, we investigated the cytotoxicity and alterations in bioenergetic metabolism induced by mitochondria-targeted vitamin E analog (Mito-chromanol, Mito-ChM) and its acetylated ester analog (Mito-ChMAc). Assays of cell death, colony formation, mitochondrial bioenergetic function, intracellular ATP levels, intracellular and tissue concentrations of tested compounds, and in vivo tumor growth were performed. Both Mito-ChM and Mito-ChMAc selectively depleted intracellular ATP and caused prolonged inhibition of ATP-linked oxygen consumption rate in breast cancer cells, but not in non-cancerous cells. These effects were significantly augmented by inhibition of glycolysis. Mito-ChM and Mito-ChMAc exhibited anti-proliferative effects and cytotoxicity in several breast cancer cells with different genetic background. Furthermore, Mito-ChM selectively accumulated in tumor tissue and inhibited tumor growth in a xenograft model of human breast cancer. We conclude that mitochondria-targeted small molecular weight chromanols exhibit selective anti-proliferative effects and cytotoxicity in multiple breast cancer cells, and that esterification of the hydroxyl group in mito-chromanols is not a critical requirement for its anti-proliferative and cytotoxic effect

  14. Synthesis of a Pilot Scale Library of 4-amino-2 (diethylaminomethyl) phenol (ADOC) Analogues for Testing of Organophosphate-Inhibited Acetylcholinesterase Reactivation Ability

    Science.gov (United States)

    2018-02-01

    Inhibited Acetylcholinesterase Reactivation Ability Zachary Canter Kevin Martin Michael Hepperle February 2018 Approved for public release; distribution...PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Canter, Z., Martin , K., Hepperle, M. 5d. PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT NUMBER 7. PERFORMING

  15. Inhibition of pancreatic tumoral cells by snake venom disintegrins.

    Science.gov (United States)

    Lucena, Sara; Castro, Roberto; Lundin, Courtney; Hofstetter, Amanda; Alaniz, Amber; Suntravat, Montamas; Sánchez, Elda Eliza

    2015-01-01

    Pancreatic cancer often has a poor prognosis, even when diagnosed early. Pancreatic cancer typically spreads rapidly and is rarely detected in its early stages, which is a major reason it is a leading cause of cancer death. Signs and symptoms may not appear until pancreatic cancer is quite advanced, and complete surgical removal is not possible. Furthermore, pancreatic cancer responds poorly to most chemotherapeutic agents. The importance of integrins in several cell types that affect tumor progression has made them an appealing target for cancer therapy. Some of the proteins found in the snake venom present a great potential as anti-tumor agents. In this study, we summarize the activity of two integrins antagonist, recombinant disintegrins mojastin 1 and viridistatin 2, on human pancreatic carcinoma cell line (BXPC-3). Both recombinant disintegrins inhibited some essential aspects of the metastasis process such as proliferation, adhesion, migration, and survival through apoptosis, making these proteins prominent candidates for the development of drugs for the treatment of pancreatic cancer. Copyright © 2014 Elsevier Ltd. All rights reserved.

  16. Human Diversity in a Cell Surface Receptor that Inhibits Autophagy.

    Science.gov (United States)

    Chaudhary, Anu; Leite, Mara; Kulasekara, Bridget R; Altura, Melissa A; Ogahara, Cassandra; Weiss, Eli; Fu, Wenqing; Blanc, Marie-Pierre; O'Keeffe, Michael; Terhorst, Cox; Akey, Joshua M; Miller, Samuel I

    2016-07-25

    Mutations in genes encoding autophagy proteins have been associated with human autoimmune diseases, suggesting that diversity in autophagy responses could be associated with disease susceptibility or severity. A cellular genome-wide association study (GWAS) screen was performed to explore normal human diversity in responses to rapamycin, a microbial product that induces autophagy. Cells from several human populations demonstrated variability in expression of a cell surface receptor, CD244 (SlamF4, 2B4), that correlated with changes in rapamycin-induced autophagy. High expression of CD244 and receptor activation with its endogenous ligand CD48 inhibited starvation- and rapamycin-induced autophagy by promoting association of CD244 with the autophagy complex proteins Vps34 and Beclin-1. The association of CD244 with this complex reduced Vps34 lipid kinase activity. Lack of CD244 is associated with auto-antibody production in mice, and lower expression of human CD244 has previously been implicated in severity of human rheumatoid arthritis and systemic lupus erythematosus, indicating that increased autophagy as a result of low levels of CD244 may alter disease outcomes. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Arsenic trioxide inhibits cell proliferation and human papillomavirus oncogene expression in cervical cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Hongtao [Department of Pathology, School of Medicine, Southeast University, Nanjing 210009 (China); Gao, Peng [Department of Internal Medicine, University of Iowa, Iowa City, IA 52242 (United States); Zheng, Jie, E-mail: jiezheng54@126.com [Department of Pathology, School of Medicine, Southeast University, Nanjing 210009 (China)

    2014-09-05

    Highlights: • As{sub 2}O{sub 3} inhibits growth of cervical cancer cells and expression of HPV oncogenes in these cells. • HPV-negative cervical cancer cells are more sensitive to As{sub 2}O{sub 3} than HPV-positive cervical cancer cells. • HPV-18 positive cervical cancer cells are more sensitive to As{sub 2}O{sub 3} than HPV-16 positive cancer cells. • Down-regulation of HPV oncogenes by As{sub 2}O{sub 3} is partially due to the diminished AP-1 binding. - Abstract: Arsenic trioxide (As{sub 2}O{sub 3}) has shown therapeutic effects in some leukemias and solid cancers. However, the molecular mechanisms of its anticancer efficacy have not been clearly elucidated, particularly in solid cancers. Our previous data showed that As{sub 2}O{sub 3} induced apoptosis of human papillomavirus (HPV) 16 DNA-immortalized human cervical epithelial cells and cervical cancer cells and inhibited the expression of HPV oncogenes in these cells. In the present study, we systemically examined the effects of As{sub 2}O{sub 3} on five human cervical cancer cell lines and explored the possible molecular mechanisms. MTT assay showed that HPV-negative C33A cells were more sensitive to growth inhibition induced by As{sub 2}O{sub 3} than HPV-positive cervical cancer cells, and HPV 18-positive HeLa and C4-I cells were more sensitive to As{sub 2}O{sub 3} than HPV 16-positive CaSki and SiHa cells. After As{sub 2}O{sub 3} treatment, both mRNA and protein levels of HPV E6 and E7 obviously decreased in all HPV positive cell lines. In contrast, p53 and Rb protein levels increased in all tested cell lines. Transcription factor AP-1 protein expression decreased significantly in HeLa, CaSki and C33A cells with ELISA method. These results suggest that As{sub 2}O{sub 3} is a potential anticancer drug for cervical cancer.

  18. Inhibition of PTP1B disrupts cell-cell adhesion and induces anoikis in breast epithelial cells.

    Science.gov (United States)

    Hilmarsdottir, Bylgja; Briem, Eirikur; Halldorsson, Skarphedinn; Kricker, Jennifer; Ingthorsson, Sævar; Gustafsdottir, Sigrun; Mælandsmo, Gunhild M; Magnusson, Magnus K; Gudjonsson, Thorarinn

    2017-05-11

    Protein tyrosine phosphatase 1B (PTP1B) is a well-known inhibitor of insulin signaling pathways and inhibitors against PTP1B are being developed as promising drug candidates for treatment of obesity. PTP1B has also been linked to breast cancer both as a tumor suppressor and as an oncogene. Furthermore, PTP1B has been shown to be a regulator of cell adhesion and migration in normal and cancer cells. In this study, we analyzed the PTP1B expression in normal breast tissue, primary breast cells and the breast epithelial cell line D492. In normal breast tissue and primary breast cells, PTP1B is widely expressed in both epithelial and stromal cells, with highest expression in myoepithelial cells and fibroblasts. PTP1B is widely expressed in branching structures generated by D492 when cultured in 3D reconstituted basement membrane (3D rBM). Inhibition of PTP1B in D492 and another mammary epithelial cell line HMLE resulted in reduced cell proliferation and induction of anoikis. These changes were seen when cells were cultured both in monolayer and in 3D rBM. PTP1B inhibition affected cell attachment, expression of cell adhesion proteins and actin polymerization. Moreover, epithelial to mesenchymal transition (EMT) sensitized cells to PTP1B inhibition. A mesenchymal sublines of D492 and HMLE (D492M and HMLEmes) were more sensitive to PTP1B inhibition than D492 and HMLE. Reversion of D492M to an epithelial state using miR-200c-141 restored resistance to detachment induced by PTP1B inhibition. In conclusion, we have shown that PTP1B is widely expressed in the human breast gland with highest expression in myoepithelial cells and fibroblasts. Inhibition of PTP1B in D492 and HMLE affects cell-cell adhesion and induces anoikis-like effects. Finally, cells with an EMT phenotype are more sensitive to PTP1B inhibitors making PTP1B a potential candidate for further studies as a target for drug development in cancer involving the EMT phenotype.

  19. Characterization of goat inner cell mass derived cells in double kinase inhibition condition

    International Nuclear Information System (INIS)

    Wei, Qiang; Xi, Qihui; Liu, Xiaokun; Meng, Kai; Zhao, Xiaoe; Ma, Baohua

    2017-01-01

    The identification of small molecular inhibitors, which were reported to promote the derivation of mouse and human embryonic stem cells (ESCs), provides a potential strategy for the derivation of domesticated ungulate ESCs. In present study, goat inner cell mass (ICM) derived cells in the double inhibition (2i) condition, in which, mitogen-activated protein kinase kinase (MAP2K) and glycogen synthase kinase 3 (GSK3) were inhibited by PD0325901 and BIO respectively, were characterized. The results showed that goat ICM derived cells in 2i medium adding leukaemia inhibitor factor (LIF) possessed a mouse ES-like morphology. But these cells had much compromised proliferation capacity, resulting in difficulty in expansion. In 2i alone medium, goat ICM derived cells possessed primate ES-like morphology. These cells expressed pluripotent markers and could differentiate into derivatives of three germ layers in vitro. However, these cells could not be proliferated in long-term (persisted for 15 passages) because of spontaneously neural differentiation. Additionally, goat ICM derived cells could be inducing differentiated into neural lineage in vitro. Although goat ESCs could not be established in PD0325901 and BIO alone medium, this derivation condition provides a useful research system to find signaling molecular those regulate early embryonic development and pluripotency in goat. - Highlights: • Goat inner cell mass derived cells possessed finite pluripotency in 2i condition. • These cells could not be proliferated in long-term in 2i condition. • These cells could spontaneously and inductively differentiate into neural lineage.

  20. Inhibition of thromboxane synthase induces lung cancer cell death via increasing the nuclear p27

    International Nuclear Information System (INIS)

    Leung, Kin Chung; Hsin, Michael K.Y.; Chan, Joey S.Y.; Yip, Johnson H.Y.; Li, Mingyue; Leung, Billy C.S.; Mok, Tony S.K.; Warner, Timothy D.; Underwood, Malcolm J.; Chen, George G.

    2009-01-01

    The role of thromboxane in lung carcinogenesis is not clearly known, though thromboxane B2 (TXB 2 ) level is increased and antagonists of thromboxane receptors or TXA2 can induce apoptosis of lung cancer cells. p27, an atypical tumor suppressor, is normally sequestered in the nucleus. The increased nuclear p27 may result in apoptosis of tumor cells. We hypothesize that the inhibition of thromboxane synthase (TXS) induces the death of lung cancer cells and that such inhibition is associated with the nuclear p27 level. Our experiment showed that the inhibition of TXS significantly induced the death or apoptosis in lung cancer cells. The activity of TXS was increased in lung cancer. The nuclear p27 was remarkably reduced in lung cancer tissues. The inhibition of TXS caused the cell death and apoptosis of lung cancer cells, likely via the elevation of the nuclear p27 since the TXS inhibition promoted the nuclear p27 level and the inhibition of p27 by its siRNA recovered the cell death induced by TXS inhibition. Collectively, lung cancer cells produce high levels of TXB 2 but their nuclear p27 is markedly reduced. The inhibition of TXS results in the p27-related induction of cell death in lung cancer cells.

  1. Inhibition of thromboxane synthase induces lung cancer cell death via increasing the nuclear p27

    Energy Technology Data Exchange (ETDEWEB)

    Leung, Kin Chung; Hsin, Michael K.Y.; Chan, Joey S.Y.; Yip, Johnson H.Y.; Li, Mingyue; Leung, Billy C.S. [Department of Surgery, The Chinese University of Hong Kong, Shatin, New Territories (Hong Kong); Mok, Tony S.K. [Department of Clinical Oncology, The Chinese University of Hong Kong, Shatin, New Territories (Hong Kong); Warner, Timothy D. [The William Harvey Research Institute, Queen Mary University of London, London (United Kingdom); Underwood, Malcolm J. [Department of Surgery, The Chinese University of Hong Kong, Shatin, New Territories (Hong Kong); Chen, George G., E-mail: gchen@cuhk.edu.hk [Department of Surgery, The Chinese University of Hong Kong, Shatin, New Territories (Hong Kong)

    2009-10-15

    The role of thromboxane in lung carcinogenesis is not clearly known, though thromboxane B2 (TXB{sub 2}) level is increased and antagonists of thromboxane receptors or TXA2 can induce apoptosis of lung cancer cells. p27, an atypical tumor suppressor, is normally sequestered in the nucleus. The increased nuclear p27 may result in apoptosis of tumor cells. We hypothesize that the inhibition of thromboxane synthase (TXS) induces the death of lung cancer cells and that such inhibition is associated with the nuclear p27 level. Our experiment showed that the inhibition of TXS significantly induced the death or apoptosis in lung cancer cells. The activity of TXS was increased in lung cancer. The nuclear p27 was remarkably reduced in lung cancer tissues. The inhibition of TXS caused the cell death and apoptosis of lung cancer cells, likely via the elevation of the nuclear p27 since the TXS inhibition promoted the nuclear p27 level and the inhibition of p27 by its siRNA recovered the cell death induced by TXS inhibition. Collectively, lung cancer cells produce high levels of TXB{sub 2} but their nuclear p27 is markedly reduced. The inhibition of TXS results in the p27-related induction of cell death in lung cancer cells.

  2. Cardiac glycosides induce cell death in human cells by inhibiting general protein synthesis.

    Directory of Open Access Journals (Sweden)

    Andrea Perne

    2009-12-01

    Full Text Available Cardiac glycosides are Na(+/K(+-pump inhibitors widely used to treat heart failure. They are also highly cytotoxic, and studies have suggested specific anti-tumor activity leading to current clinical trials in cancer patients. However, a definitive demonstration of this putative anti-cancer activity and the underlying molecular mechanism has remained elusive.Using an unbiased transcriptomics approach, we found that cardiac glycosides inhibit general protein synthesis. Protein synthesis inhibition and cytotoxicity were not specific for cancer cells as they were observed in both primary and cancer cell lines. These effects were dependent on the Na(+/K(+-pump as they were rescued by expression of a cardiac glycoside-resistant Na(+/K(+-pump. Unlike human cells, rodent cells are largely resistant to cardiac glycosides in vitro and mice were found to tolerate extremely high levels.The physiological difference between human and mouse explains the previously observed sensitivity of human cancer cells in mouse xenograft experiments. Thus, published mouse xenograft models used to support anti-tumor activity for these drugs require reevaluation. Our finding that cardiac glycosides inhibit protein synthesis provides a mechanism for the cytotoxicity of CGs and raises concerns about ongoing clinical trials to test CGs as anti-cancer agents in humans.

  3. Lycopene inhibits the cell proliferation and invasion of human head and neck squamous cell carcinoma.

    Science.gov (United States)

    Ye, Min; Wu, Qundan; Zhang, Min; Huang, Jinbei

    2016-10-01

    Lycopene has been shown to be associated with anticancer effects in numerous tumor types. However, the underlying mechanisms of lycopene in human head and neck squamous cell carcinoma (HNSCC) remain to be determined. The present study aimed to investigate the involvement of lycopene overload and the cytotoxic effects of lycopene on HNSCC cells, and to determine the possible mechanisms involved. Treatment with lycopene at a dose of >10 µM for >24 h inhibited the growth of FaDu and Cal27 cells in a time‑ and dose‑dependent manner. The clearest increase in growth inhibition was due to the apoptotic population being significantly increased. The invasion abilities decreased with 25 µM lycopene exerting significant inhibitory effects (Plycopene induced the upregulation of the pro‑apoptotic protein, B‑cell lymphoma‑associated X protein, and therefore, resulted in the inhibition of the protein kinase B and mitogen‑activated protein kinase signaling pathway. These data provided insights into the antitumor activity of lycopene in HNSCC cells.

  4. Indole Alkaloids Inhibiting Neural Stem Cell from Uncaria rhynchophylla

    OpenAIRE

    Wei, Xin; Jiang, Li-Ping; Guo, Ying; Khan, Afsar; Liu, Ya-Ping; Yu, Hao-Fei; Wang, Bei; Ding, Cai-Feng; Zhu, Pei-Feng; Chen, Ying-Ying; Zhao, Yun-Li; Chen, Yong-Bing; Wang, Yi-Fen; Luo, Xiao-Dong

    2017-01-01

    Uncaria rhynchophylla is commonly recognized as a traditional treatment for dizziness, cerebrovascular diseases, and nervous disorders in China. Previously, the neuro-protective activities of the alkaloids from U. rhynchophylla were intensively reported. In current work, three new indole alkaloids (1–3), identified as geissoschizic acid (1), geissoschizic acid N 4-oxide (2), and 3β-sitsirikine N 4-oxide (3), as well as 26 known analogues were isolated from U. rhynchophylla. However, in the ne...

  5. A small-molecule/cytokine combination enhances hematopoietic stem cell proliferation via inhibition of cell differentiation.

    Science.gov (United States)

    Wang, Lan; Guan, Xin; Wang, Huihui; Shen, Bin; Zhang, Yu; Ren, Zhihua; Ma, Yupo; Ding, Xinxin; Jiang, Yongping

    2017-07-18

    Accumulated evidence supports the potent stimulating effects of multiple small molecules on the expansion of hematopoietic stem cells (HSCs) which are important for the therapy of various hematological disorders. Here, we report a novel, optimized formula, named the SC cocktail, which contains a combination of three such small molecules and four cytokines. Small-molecule candidates were individually screened and then combined at their optimal concentration with the presence of cytokines to achieve maximum capacity for stimulating the human CD34 + cell expansion ex vivo. The extent of cell expansion and the immunophenotype of expanded cells were assessed through flow cytometry. The functional preservation of HSC stemness was confirmed by additional cell and molecular assays in vitro. Subsequently, the expanded cells were transplanted into sublethally irradiated NOD/SCID mice for the assessment of human cell viability and engraftment potential in vivo. Furthermore, the expression of several genes in the cell proliferation and differentiation pathways was analyzed through quantitative polymerase chain reaction (qPCR) during the process of CD34 + cell expansion. The SC cocktail supported the retention of the immunophenotype of hematopoietic stem/progenitor cells remarkably well, by yielding purities of 86.6 ± 11.2% for CD34 + cells and 76.2 ± 10.5% for CD34 + CD38 - cells, respectively, for a 7-day culture. On day 7, the enhancement of expansion of CD34 + cells and CD34 + CD38 - cells reached a maxima of 28.0 ± 5.5-fold and 27.9 ± 4.3-fold, respectively. The SC cocktail-expanded CD34 + cells preserved the characteristics of HSCs by effectively inhibiting their differentiation in vitro and retained the multilineage differentiation potential in primary and secondary in vivo murine xenotransplantation trials. Further gene expression analysis suggested that the small-molecule combination strengthened the ability of the cytokines to enhance the Notch

  6. Bevacizumab inhibits proliferation of choroidal endothelial cells by regulation of the cell cycle.

    Science.gov (United States)

    Rusovici, Raluca; Patel, Chirag J; Chalam, Kakarla V

    2013-01-01

    The purpose of this study was to evaluate cell cycle changes in choroidal endothelial cells treated with varying doses of bevacizumab in the presence of a range of concentrations of vascular endothelial growth factor (VEGF). Bevacizumab, a drug widely used in the treatment of neovascular age-related macular degeneration, choroidal neovascularization, and proliferative diabetic retinopathy, neutralizes all isoforms of VEGF. However, the effect of intravitreal administration of bevacizumab on the choroidal endothelial cell cycle has not been established. Monkey choroidal endothelial (RF/6A) cells were treated with VEGF 50 ng/mL and escalating doses of bevacizumab 0.1-2 mg/mL for 72 hours. Cell cycle changes in response to bevacizumab were analyzed by flow cytometry and propidium iodide staining. Cell proliferation was measured using the WST-1 assay. Morphological changes were recorded by bright field cell microscopy. Bevacizumab inhibited proliferation of choroidal endothelial cells by stabilization of the cell cycle in G0/G1 phase. Cell cycle analysis of VEGF-enriched choroidal endothelial cells revealed a predominant increase in the G2/M population (21.84%, P, 0.01) and a decrease in the G0/G1 phase population (55.08%, P, 0.01). Addition of escalating doses of bevacizumab stabilized VEGF-enriched cells in the G0/G1 phase (55.08%, 54.49%, 56.3%, and 64% [P, 0.01]) and arrested proliferation by inhibiting the G2/M phase (21.84%, 21.46%, 20.59%, 20.94%, and 16.1% [P, 0.01]). The increase in G0/G1 subpopulation in VEGF-enriched and bevacizumab-treated cells compared with VEGF-enriched cells alone was dose-dependent. Bevacizumab arrests proliferation of VEGF-enriched choroidal endothelial cells by stabilizing the cell cycle in the G0/G1 phase and inhibiting the G2/M phase in a dose-dependent fashion.

  7. Mesenchymal stem cells with rhBMP-2 inhibits the growth of canine osteosarcoma cells

    Directory of Open Access Journals (Sweden)

    Grassi Rici Rose

    2012-02-01

    Full Text Available Abstract Background The bone morphogenetic proteins (BMPs belong to a unique group of proteins that includes the growth factor TGF-β. BMPs play important roles in cell differentiation, cell proliferation, and inhibition of cell growth. They also participate in the maturation of several cell types, depending on the microenvironment and interactions with other regulatory factors. Depending on their concentration gradient, the BMPs can attract various types of cells and act as chemotactic, mitogenic, or differentiation agents. BMPs can interfere with cell proliferation and the formation of cartilage and bone. In addition, BMPs can induce the differentiation of mesenchymal progenitor cells into various cell types, including chondroblasts and osteoblasts. The aim of this study was to analyze the effects of treatment with rhBMP-2 on the proliferation of canine mesenchymal stem cells (cMSCs and the tumor suppression properties of rhBMP-2 in canine osteocarcoma (OST cells. Osteosarcoma cell lines were isolated from biopsies and excisions of animals with osteosarcoma and were characterized by the Laboratory of Biochemistry and Biophysics, Butantan Institute. The mesenchymal stem cells were derived from the bone marrow of canine fetuses (cMSCs and belong to the University of São Paulo, College of Veterinary Medicine (FMVZ-USP stem cell bank. After expansion, the cells were cultured in a 12-well Transwell system; cells were treated with bone marrow mesenchymal stem cells associated with rhBMP2. Expression of the intracytoplasmic and nuclear markers such as Caspase-3, Bax, Bad, Bcl-2, Ki-67, p53, Oct3/4, Nanog, Stro-1 were performed by flow citometry. Results We evaluated the regenerative potential of in vitro treatment with rhBMP-2 and found that both osteogenic induction and tumor regression occur in stem cells from canine bone marrow. rhBMP-2 inhibits the proliferation capacity of OST cells by mechanisms of apoptosis and tumor suppression mediated by p

  8. Mesenchymal stem cells with rhBMP-2 inhibits the growth of canine osteosarcoma cells.

    Science.gov (United States)

    Rici, Rose Eli Grassi; Alcântara, Dayane; Fratini, Paula; Wenceslau, Cristiane Valverde; Ambrósio, Carlos Eduardo; Miglino, Maria Angelica; Maria, Durvanei Augusto

    2012-02-22

    The bone morphogenetic proteins (BMPs) belong to a unique group of proteins that includes the growth factor TGF-β. BMPs play important roles in cell differentiation, cell proliferation, and inhibition of cell growth. They also participate in the maturation of several cell types, depending on the microenvironment and interactions with other regulatory factors. Depending on their concentration gradient, the BMPs can attract various types of cells and act as chemotactic, mitogenic, or differentiation agents. BMPs can interfere with cell proliferation and the formation of cartilage and bone. In addition, BMPs can induce the differentiation of mesenchymal progenitor cells into various cell types, including chondroblasts and osteoblasts. The aim of this study was to analyze the effects of treatment with rhBMP-2 on the proliferation of canine mesenchymal stem cells (cMSCs) and the tumor suppression properties of rhBMP-2 in canine osteocarcoma (OST) cells. Osteosarcoma cell lines were isolated from biopsies and excisions of animals with osteosarcoma and were characterized by the Laboratory of Biochemistry and Biophysics, Butantan Institute. The mesenchymal stem cells were derived from the bone marrow of canine fetuses (cMSCs) and belong to the University of São Paulo, College of Veterinary Medicine (FMVZ-USP) stem cell bank. After expansion, the cells were cultured in a 12-well Transwell system; cells were treated with bone marrow mesenchymal stem cells associated with rhBMP2. Expression of the intracytoplasmic and nuclear markers such as Caspase-3, Bax, Bad, Bcl-2, Ki-67, p53, Oct3/4, Nanog, Stro-1 were performed by flow citometry. We evaluated the regenerative potential of in vitro treatment with rhBMP-2 and found that both osteogenic induction and tumor regression occur in stem cells from canine bone marrow. rhBMP-2 inhibits the proliferation capacity of OST cells by mechanisms of apoptosis and tumor suppression mediated by p53. We propose that rhBMP-2 has great

  9. Atorvastatin inhibits insulin synthesis by inhibiting the Ras/Raf/ERK/CREB pathway in INS-1 cells

    Science.gov (United States)

    Sun, Hongxi; Li, Yu; Sun, Bei; Hou, Ningning; Yang, Juhong; Zheng, Miaoyan; Xu, Jie; Wang, Jingyu; Zhang, Yi; Zeng, Xianwei; Shan, Chunyan; Chang, Bai; Chen, Liming; Chang, Baocheng

    2016-01-01

    Abstract Backround: Type 2 diabetes has become a global epidemic disease. Atorvastatin has become a cornerstone in the prevention and treatment of atherosclerosis. However, increasing evidence showed that statins can dose-dependently increase the risk of diabetes mellitus. The mechanism is not clear. Objective: The Ras complex pathway (Ras/Raf/extracellular signal-regulated kinase [ERK]/cAMP response element-binding protein [CREB]) is the major pathway that regulates the gene transcription. Except for the inhibition of cholesterol synthesis by inhibiting the 3-hydroxy-3-methyl glutaryl coenzyme A (HMG-COA) reductase, statins can also downregulate the phosphorylation of a series of downstream substrates including the key proteins of the Ras complex pathway, therefore may inhibit the insulin syntheses in pancreatic beta cells. In our study, we investigated the inhibitory effect and the underlying mechanism of atorvastatin on insulin synthesis in rat islets. Methods: Islets were isolated from Wistar rats and cultured in Roswell Park Memorial Institute (RPMI)-1640 medium. The insulin content in the medium was measured by radioimmunoassay before and after the treatment of 50 μM atorvastatin. Effect of atorvastatin on the expression of insulin message Ribonucleic acid (mRNA) in pancreatic islet beta cells was also detected using quantitative real-time polymerase chain reaction. Western blotting was used to explore the possible role of the Ras complex pathway (Ras/Raf/ERK/CREB) in atorvastatin-inhibited insulin synthesis. The effects of atorvastatin on the binding of nuclear transcription factor p-CREB with CRE in INS-1 cells were examined via chromatin immunoprecipitation assay. Results: Compared with the control group, the insulin level decreased by 27.1% at 24 hours after atorvastatin treatment. Atorvastatin inhibited insulin synthesis by decreasing insulin mRNA expression of pancreatic islet beta cells. The activities of Ras, Raf-1, and p-CREB in the Ras complex

  10. Transient inhibition of cell proliferation does not compromise self-renewal of mouse embryonic stem cells.

    Science.gov (United States)

    Wang, Ruoxing; Guo, Yan-Lin

    2012-10-01

    Embryonic stem cells (ESCs) have unlimited capacity for self-renewal and can differentiate into various cell types when induced. They also have an unusual cell cycle control mechanism driven by constitutively active cyclin dependent kinases (Cdks). In mouse ESCs (mESCs). It is proposed that the rapid cell proliferation could be a necessary part of mechanisms that maintain mESC self-renewal and pluripotency, but this hypothesis is not in line with the finding in human ESCs (hESCs) that the length of the cell cycle is similar to differentiated cells. Therefore, whether rapid cell proliferation is essential for the maintenance of mESC state remains unclear. We provide insight into this uncertainty through chemical intervention of mESC cell cycle. We report here that inhibition of Cdks with olomoucine II can dramatically slow down cell proliferation of mESCs with concurrent down-regulation of cyclin A, B and E, and the activation of the Rb pathway. However, mESCs display can recover upon the removal of olomoucine II and are able to resume normal cell proliferation without losing self-renewal and pluripotency, as demonstrated by the expression of ESC markers, colony formation, embryoid body formation, and induced differentiation. We provide a mechanistic explanation for these observations by demonstrating that Oct4 and Nanog, two major transcription factors that play critical roles in the maintenance of ESC properties, are up-regulated via de novo protein synthesis when the cells are exposed to olomoucine II. Together, our data suggest that short-term inhibition of cell proliferation does not compromise the basic properties of mESCs. Copyright © 2012 Elsevier Inc. All rights reserved.

  11. Transient inhibition of cell proliferation does not compromise self-renewal of mouse embryonic stem cells

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Ruoxing [Department of Biological Sciences, The University of Southern Mississippi, 118 College Drive 5018, Hattiesburg, MS 39406 (United States); Guo, Yan-Lin, E-mail: yanlin.guo@usm.edu [Department of Biological Sciences, The University of Southern Mississippi, 118 College Drive 5018, Hattiesburg, MS 39406 (United States)

    2012-10-01

    Embryonic stem cells (ESCs) have unlimited capacity for self-renewal and can differentiate into various cell types when induced. They also have an unusual cell cycle control mechanism driven by constitutively active cyclin dependent kinases (Cdks). In mouse ESCs (mESCs). It is proposed that the rapid cell proliferation could be a necessary part of mechanisms that maintain mESC self-renewal and pluripotency, but this hypothesis is not in line with the finding in human ESCs (hESCs) that the length of the cell cycle is similar to differentiated cells. Therefore, whether rapid cell proliferation is essential for the maintenance of mESC state remains unclear. We provide insight into this uncertainty through chemical intervention of mESC cell cycle. We report here that inhibition of Cdks with olomoucine II can dramatically slow down cell proliferation of mESCs with concurrent down-regulation of cyclin A, B and E, and the activation of the Rb pathway. However, mESCs display can recover upon the removal of olomoucine II and are able to resume normal cell proliferation without losing self-renewal and pluripotency, as demonstrated by the expression of ESC markers, colony formation, embryoid body formation, and induced differentiation. We provide a mechanistic explanation for these observations by demonstrating that Oct4 and Nanog, two major transcription factors that play critical roles in the maintenance of ESC properties, are up-regulated via de novo protein synthesis when the cells are exposed to olomoucine II. Together, our data suggest that short-term inhibition of cell proliferation does not compromise the basic properties of mESCs. -- Highlights: Black-Right-Pointing-Pointer Inhibition of Cdks slows down mESCs proliferation. Black-Right-Pointing-Pointer mESCs display remarkable recovery capacity from short-term cell cycle interruption. Black-Right-Pointing-Pointer Short-term cell cycle interruption does not compromise mESC self-renewal. Black

  12. Transient inhibition of cell proliferation does not compromise self-renewal of mouse embryonic stem cells

    International Nuclear Information System (INIS)

    Wang, Ruoxing; Guo, Yan-Lin

    2012-01-01

    Embryonic stem cells (ESCs) have unlimited capacity for self-renewal and can differentiate into various cell types when induced. They also have an unusual cell cycle control mechanism driven by constitutively active cyclin dependent kinases (Cdks). In mouse ESCs (mESCs). It is proposed that the rapid cell proliferation could be a necessary part of mechanisms that maintain mESC self-renewal and pluripotency, but this hypothesis is not in line with the finding in human ESCs (hESCs) that the length of the cell cycle is similar to differentiated cells. Therefore, whether rapid cell proliferation is essential for the maintenance of mESC state remains unclear. We provide insight into this uncertainty through chemical intervention of mESC cell cycle. We report here that inhibition of Cdks with olomoucine II can dramatically slow down cell proliferation of mESCs with concurrent down-regulation of cyclin A, B and E, and the activation of the Rb pathway. However, mESCs display can recover upon the removal of olomoucine II and are able to resume normal cell proliferation without losing self-renewal and pluripotency, as demonstrated by the expression of ESC markers, colony formation, embryoid body formation, and induced differentiation. We provide a mechanistic explanation for these observations by demonstrating that Oct4 and Nanog, two major transcription factors that play critical roles in the maintenance of ESC properties, are up-regulated via de novo protein synthesis when the cells are exposed to olomoucine II. Together, our data suggest that short-term inhibition of cell proliferation does not compromise the basic properties of mESCs. -- Highlights: ► Inhibition of Cdks slows down mESCs proliferation. ► mESCs display remarkable recovery capacity from short-term cell cycle interruption. ► Short-term cell cycle interruption does not compromise mESC self-renewal. ► Oct4 and Nanog are up-regulated via de novo synthesis by cell cycle interruption.

  13. Inhibition of S-adenosylmethionine decarboxylase and diamine oxidase activities by analogues of methylglyoxal bis(guanylhydrazone) and their cellular uptake during lymphocyte activation.

    OpenAIRE

    Jänne, J; Morris, D R

    1984-01-01

    Several congeners of methylglyoxal bis(guanylhydrazone) were tested for their ability to inhibit eukaryotic putrescine-activated S-adenosylmethionine decarboxylase (EC 4.1.1.50) and intestinal diamine oxidase (EC 1.4.3.6). All the compounds tested, namely methylglyoxal bis(guanylhydrazone), ethylglyoxal bis(guanylhydrazone), dimethylglyoxal bis(guanylhydrazone) and the di-N"-methyl derivative of methylglyoxal bis(guanylhydrazone), were strong inhibitors of both yeast and mouse liver adenosylm...

  14. Retinoic acid and cAMP inhibit rat hepatocellular carcinoma cell proliferation and enhance cell differentiation

    Energy Technology Data Exchange (ETDEWEB)

    Ionta, M. [Instituto de Ciências Biomédicas, Universidade Federal de Alfenas, Alfenas MG (Brazil); Departamento de Biologia Celular e do Desenvolvimento, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo SP (Brazil); Rosa, M.C.; Almeida, R.B.; Freitas, V.M.; Rezende-Teixeira, P.; Machado-Santelli, G.M. [Departamento de Biologia Celular e do Desenvolvimento, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo SP (Brazil)

    2012-05-25

    Hepatocellular carcinoma (HCC) is the third highest cause of cancer death worldwide. In general, the disease is diagnosed at an advanced stage when potentially curative therapies are no longer feasible. For this reason, it is very important to develop new therapeutic approaches. Retinoic acid (RA) is a natural derivative of vitamin A that regulates important biological processes including cell proliferation and differentiation. In vitro studies have shown that RA is effective in inhibiting growth of HCC cells; however, responsiveness to treatment varies among different HCC cell lines. The objective of the present study was to determine if the combined use of RA (0.1 µM) and cAMP (1 mM), an important second messenger, improves the responsiveness of HCC cells to RA treatment. We evaluated the proliferative behavior of an HCC cell line (HTC) and the expression profile of genes related to cancer signaling pathway (ERK and GSK-3β) and liver differentiation [E-cadherin, connexin 26 (Cx26), and connexin 32 (Cx32)]. RA and cAMP were effective in inhibiting the proliferation of HTC cells independently of combined use. However, when a mixture of RA and cAMP was used, the signals concerning the degree of cell differentiation were increased. As demonstrated by Western blot, the treatment increased E-cadherin, Cx26, Cx32 and Ser9-GSK-3β (inactive form) expression while the expression of Cx43, Tyr216-GSK-3β (active form) and phosphorylated ERK decreased. Furthermore, telomerase activity was inhibited along treatment. Taken together, the results showed that the combined use of RA and cAMP is more effective in inducing differentiation of HTC cells.

  15. SHP1-mediated cell cycle redistribution inhibits radiosensitivity of non-small cell lung cancer

    International Nuclear Information System (INIS)

    Cao, Rubo; Ding, Qian; Li, Pindong; Xue, Jun; Zou, Zhenwei; Huang, Jing; Peng, Gang

    2013-01-01

    Radioresistance is the common cause for radiotherapy failure in non-small cell lung cancer (NSCLC), and the degree of radiosensitivity of tumor cells is different during different cell cycle phases. The objective of the present study was to investigate the effects of cell cycle redistribution in the establishment of radioresistance in NSCLC, as well as the signaling pathway of SH2 containing Tyrosine Phosphatase (SHP1). A NSCLC subtype cell line, radioresistant A549 (A549S1), was induced by high-dose hypofractionated ionizing radiations. Radiosensitivity-related parameters, cell cycle distribution and expression of cell cycle-related proteins and SHP1 were investigated. siRNA was designed to down-regulate SHP1expression. Compared with native A549 cells, the proportion of cells in the S phase was increased, and cells in the G0/G1 phase were consequently decreased, however, the proportion of cells in the G2/M phase did not change in A549S1 cells. Moreover, the expression of SHP1, CDK4 and CylinD1 were significantly increased, while p16 was significantly down-regulated in A549S1 cells compared with native A549 cells. Furthermore, inhibition of SHP1 by siRNA increased the radiosensitivity of A549S1 cells, induced a G0/G1 phase arrest, down-regulated CDK4 and CylinD1expressions, and up-regulated p16 expression. SHP1 decreases the radiosensitivity of NSCLC cells through affecting cell cycle distribution. This finding could unravel the molecular mechanism involved in NSCLC radioresistance

  16. Histone deacetylase inhibition regulates inflammation and enhances Tregs after allogeneic hematopoietic cell transplantation in humans

    NARCIS (Netherlands)

    Choi, S.W.; Gatza, E.; Hou, G.; Sun, Y; Whitfield, J.; Song, Y.; Oravecz-Wilson, K.; Tawara, I.; Dinarello, C.A.; Reddy, P.

    2015-01-01

    We examined immunological responses in patients receiving histone deacetylase (HDAC) inhibition (vorinostat) for graft-versus-host disease prophylaxis after allogeneic hematopoietic cell transplant. Vorinostat treatment increased histone acetylation in peripheral blood mononuclear cells (PBMCs) from

  17. Analogue MIMO Detection

    Directory of Open Access Journals (Sweden)

    McNamara Darren

    2006-01-01

    Full Text Available In this contribution we propose an analogue receiver that can perform turbo detection in MIMO systems. We present the case for a receiver that is built from nonlinear analogue devices, which perform detection in a "free-flow" network (no notion of iterations. This contribution can be viewed as an extension of analogue turbo decoder concepts to include MIMO detection. These first analogue implementations report reductions of few orders of magnitude in the number of required transistors and in consumed energy, and the same order of improvement in processing speed. It is anticipated that such analogue MIMO decoder could bring about the same advantages, when compared to traditional digital implementations.

  18. Acute ethanol exposure inhibits silencing of cerebellar Golgi cell firing induced by granule cell axon input

    Directory of Open Access Journals (Sweden)

    Paolo eBotta

    2014-02-01

    Full Text Available Golgi cells (GoCs are specialized interneurons that provide inhibitory input to granule cells in the cerebellar cortex. GoCs are pacemaker neurons that spontaneously fire action potentials, triggering spontaneous inhibitory postsynaptic currents in granule cells and also contributing to the generation tonic GABAA receptor-mediated currents in granule cells. In turn, granule cell axons provide feedback glutamatergic input to GoCs. It has been shown that high frequency stimulation of granule cell axons induces a transient pause in GoC firing in a type 2-metabotropic glutamate receptor (mGluR2-dependent manner. Here, we investigated the effect ethanol on the pause of GoC firing induced by high frequency stimulation of granule cell axons. GoC electrophysiological recordings were performed in parasagittal cerebellar vermis slices from postnatal day 23 to 26 rats. Loose-patch cell-attached recordings revealed that ethanol (40 mM reversibly decreases the pause duration. An antagonist of mGluR2 reduced the pause duration but did not affect the effect of ethanol. Whole-cell voltage-clamp recordings showed that currents evoked by an mGluR2 agonist were not significantly affected by ethanol. Perforated-patch experiments in which hyperpolarizing and depolarizing currents were injected into GoCs demonstrated that there is an inverse relationship between spontaneous firing and pause duration. Slight inhibition of the Na+/K+ pump mimicked the effect of ethanol on pause duration. In conclusion, ethanol reduces the granule cell axon-mediated feedback mechanism by reducing the input responsiveness of GoCs. This would result in a transient increase of GABAA receptor-mediated inhibition of granule cells, limiting information flow at the input stage of the cerebellar cortex.

  19. Stable SET knockdown in breast cell carcinoma inhibits cell migration and invasion

    Energy Technology Data Exchange (ETDEWEB)

    Li, Jie [Department of Occupational Health and Occupational Medicine, School of Public Health and Tropical Medicine, Southern Medical University, Guangzhou (China); Key Laboratory of Modern Toxicology of Shenzhen, Shenzhen Center for Disease Control and Prevention, Shenzhen (China); Yang, Xi-fei [Key Laboratory of Modern Toxicology of Shenzhen, Shenzhen Center for Disease Control and Prevention, Shenzhen (China); Ren, Xiao-hu [Department of Occupational Health and Occupational Medicine, School of Public Health and Tropical Medicine, Southern Medical University, Guangzhou (China); Key Laboratory of Modern Toxicology of Shenzhen, Shenzhen Center for Disease Control and Prevention, Shenzhen (China); Meng, Xiao-jing [Department of Occupational Health and Occupational Medicine, School of Public Health and Tropical Medicine, Southern Medical University, Guangzhou (China); Huang, Hai-yan [Key Laboratory of Modern Toxicology of Shenzhen, Shenzhen Center for Disease Control and Prevention, Shenzhen (China); Zhao, Qiong-hui [Shenzhen Entry-Exit Inspection and Quarantine Bureau, Shenzhen (China); Yuan, Jian-hui; Hong, Wen-xu; Xia, Bo; Huang, Xin-feng; Zhou, Li [Key Laboratory of Modern Toxicology of Shenzhen, Shenzhen Center for Disease Control and Prevention, Shenzhen (China); Liu, Jian-jun, E-mail: bio-research@hotmail.com [Key Laboratory of Modern Toxicology of Shenzhen, Shenzhen Center for Disease Control and Prevention, Shenzhen (China); Zou, Fei, E-mail: zoufei616@163.com [Department of Occupational Health and Occupational Medicine, School of Public Health and Tropical Medicine, Southern Medical University, Guangzhou (China)

    2014-10-10

    Highlights: • We employed RNA interference to knockdown SET expression in breast cancer cells. • Knockdown of SET expression inhibits cell proliferation, migration and invasion. • Knockdown of SET expression increases the activity and expression of PP2A. • Knockdown of SET expression decreases the expression of MMP-9. - Abstract: Breast cancer is the most malignant tumor for women, however, the mechanisms underlying this devastating disease remain unclear. SET is an endogenous inhibitor of protein phosphatase 2A (PP2A) and involved in many physiological and pathological processes. SET could promote the occurrence of tumor through inhibiting PP2A. In this study, we explore the role of SET in the migration and invasion of breast cancer cells MDA-MB-231 and ZR-75-30. The stable suppression of SET expression through lentivirus-mediated RNA interference (RNAi) was shown to inhibit the growth, migration and invasion of breast cancer cells. Knockdown of SET increases the activity and expression of PP2Ac and decrease the expression of matrix metalloproteinase 9 (MMP-9). These data demonstrate that SET may be involved in the pathogenic processes of breast cancer, indicating that SET can serve as a potential therapeutic target for the treatment of breast cancer.

  20. Stable SET knockdown in breast cell carcinoma inhibits cell migration and invasion

    International Nuclear Information System (INIS)

    Li, Jie; Yang, Xi-fei; Ren, Xiao-hu; Meng, Xiao-jing; Huang, Hai-yan; Zhao, Qiong-hui; Yuan, Jian-hui; Hong, Wen-xu; Xia, Bo; Huang, Xin-feng; Zhou, Li; Liu, Jian-jun; Zou, Fei

    2014-01-01

    Highlights: • We employed RNA interference to knockdown SET expression in breast cancer cells. • Knockdown of SET expression inhibits cell proliferation, migration and invasion. • Knockdown of SET expression increases the activity and expression of PP2A. • Knockdown of SET expression decreases the expression of MMP-9. - Abstract: Breast cancer is the most malignant tumor for women, however, the mechanisms underlying this devastating disease remain unclear. SET is an endogenous inhibitor of protein phosphatase 2A (PP2A) and involved in many physiological and pathological processes. SET could promote the occurrence of tumor through inhibiting PP2A. In this study, we explore the role of SET in the migration and invasion of breast cancer cells MDA-MB-231 and ZR-75-30. The stable suppression of SET expression through lentivirus-mediated RNA interference (RNAi) was shown to inhibit the growth, migration and invasion of breast cancer cells. Knockdown of SET increases the activity and expression of PP2Ac and decrease the expression of matrix metalloproteinase 9 (MMP-9). These data demonstrate that SET may be involved in the pathogenic processes of breast cancer, indicating that SET can serve as a potential therapeutic target for the treatment of breast cancer

  1. Baicalein induces cell death in murine T cell lymphoma via inhibition of thioredoxin system.

    Science.gov (United States)

    Patwardhan, Raghavendra S; Pal, Debojyoti; Checker, Rahul; Sharma, Deepak; Sandur, Santosh K

    2017-10-01

    We have earlier demonstrated the radioprotective potential of baicalein using murine splenic lymphocytes. Here, we have studied the effect of baicalein on murine T cell lymphoma EL4 cells and investigated the underlying mechanism of action. We observed that baicalein induced a dose dependent cell death in EL4 cells in vitro and significantly reduced the frequency of cancer stem cells. Previously, we have reported that murine and human T cell lymphoma cells have increased oxidative stress tolerance capacity due to active thioredoxin system. Hence, we monitored the effect of baicalein on thioredoxin system in EL4 cells. Docking studies revealed that baicalein could bind to the active site of thioredoxin reductase. Baicalein treatment led to significant reduction in the activity of thioredoxin reductase and nuclear levels of thioredoxin-1 thereby increasing ASK1 levels and caspase-3 activity. Interestingly, CRISPR-Cas9 based knock-out of ASK1 or over-expression of thioredoxin-1 abolished anti-tumor effects of baicalein in EL4 cells. Further, baicalein administration significantly reduced intra-peritoneal tumor burden of EL4 cells in C57BL/6 mice. Thus, our study describes anti-tumor effects of baicalein in EL4 cells via inhibition of thioredoxin system. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Infantile hemangioma-derived stem cells and endothelial cells are inhibited by class 3 semaphorins

    International Nuclear Information System (INIS)

    Nakayama, Hironao; Huang, Lan; Kelly, Ryan P.; Oudenaarden, Clara R.L.; Dagher, Adelle; Hofmann, Nicole A.; Moses, Marsha A.; Bischoff, Joyce; Klagsbrun, Michael

    2015-01-01

    Class 3 semaphorins were discovered as a family of axon guidance molecules, but are now known to be involved in diverse biologic processes. In this study, we investigated the anti-angiogenic potential of SEMA3E and SEMA3F (SEMA3E&F) in infantile hemangioma (IH). IH is a common vascular tumor that involves both vasculogenesis and angiogenesis. Our lab has identified and isolated hemangioma stem cells (HemSC), glucose transporter 1 positive (GLUT1 + ) endothelial cells (designated as GLUT1 sel cells) based on anti-GLUT1 magnetic beads selection and GLUT1-negative endothelial cells (named HemEC). We have shown that these types of cells play important roles in hemangiogenesis. We report here that SEMA3E inhibited HemEC migration and proliferation while SEMA3F was able to suppress the migration and proliferation in all three types of cells. Confocal microscopy showed that stress fibers in HemEC were reduced by SEMA3E&F and that stress fibers in HemSC were decreased by SEMA3F, which led to cytoskeletal collapse and loss of cell motility in both cell types. Additionally, SEMA3E&F were able to inhibit vascular endothelial growth factor (VEGF)-induced sprouts in all three types of cells. Further, SEMA3E&F reduced the level of p-VEGFR2 and its downstream p-ERK in HemEC. These results demonstrate that SEMA3E&F inhibit IH cell proliferation and suppress the angiogenic activities of migration and sprout formation. SEMA3E&F may have therapeutic potential to treat or prevent growth of highly proliferative IH. - Highlights: • SEMA3E&F reduce actin stress fibers and induce cytoskeletal collapse in HemEC. • SEMA3E&F inhibit angiogenic activities of HemEC. • SEMA3E&F can interrupt the VEGF-A-VEGFR2-ERK signaling pathway in HemEC. • Plexin D1 and NRP2 are induced during HemSC/GLUT1 sel -to-EC differentiation

  3. Infantile hemangioma-derived stem cells and endothelial cells are inhibited by class 3 semaphorins

    Energy Technology Data Exchange (ETDEWEB)

    Nakayama, Hironao [Vascular Biology Program, Boston Children' s Hospital, Harvard Medical School, Boston, MA 02115 (United States); Department of Surgery, Boston Children' s Hospital, Harvard Medical School, Boston, MA 02115 (United States); Division of Cell Growth and Tumor Regulation, Proteo-Science Center, Ehime University, Toon, Ehime 791-0295 (Japan); Huang, Lan [Vascular Biology Program, Boston Children' s Hospital, Harvard Medical School, Boston, MA 02115 (United States); Department of Surgery, Boston Children' s Hospital, Harvard Medical School, Boston, MA 02115 (United States); Kelly, Ryan P.; Oudenaarden, Clara R.L. [Vascular Biology Program, Boston Children' s Hospital, Harvard Medical School, Boston, MA 02115 (United States); Dagher, Adelle; Hofmann, Nicole A.; Moses, Marsha A. [Vascular Biology Program, Boston Children' s Hospital, Harvard Medical School, Boston, MA 02115 (United States); Department of Surgery, Boston Children' s Hospital, Harvard Medical School, Boston, MA 02115 (United States); Bischoff, Joyce, E-mail: joyce.bischoff@childrens.harvard.edu [Vascular Biology Program, Boston Children' s Hospital, Harvard Medical School, Boston, MA 02115 (United States); Department of Surgery, Boston Children' s Hospital, Harvard Medical School, Boston, MA 02115 (United States); Klagsbrun, Michael, E-mail: michael.klagsbrun@childrens.harvard.edu [Vascular Biology Program, Boston Children' s Hospital, Harvard Medical School, Boston, MA 02115 (United States); Department of Surgery, Boston Children' s Hospital, Harvard Medical School, Boston, MA 02115 (United States); Department of Pathology, Boston Children' s Hospital, Harvard Medical School, Boston, MA 02115 (United States)

    2015-08-14

    Class 3 semaphorins were discovered as a family of axon guidance molecules, but are now known to be involved in diverse biologic processes. In this study, we investigated the anti-angiogenic potential of SEMA3E and SEMA3F (SEMA3E&F) in infantile hemangioma (IH). IH is a common vascular tumor that involves both vasculogenesis and angiogenesis. Our lab has identified and isolated hemangioma stem cells (HemSC), glucose transporter 1 positive (GLUT1{sup +}) endothelial cells (designated as GLUT1{sup sel} cells) based on anti-GLUT1 magnetic beads selection and GLUT1-negative endothelial cells (named HemEC). We have shown that these types of cells play important roles in hemangiogenesis. We report here that SEMA3E inhibited HemEC migration and proliferation while SEMA3F was able to suppress the migration and proliferation in all three types of cells. Confocal microscopy showed that stress fibers in HemEC were reduced by SEMA3E&F and that stress fibers in HemSC were decreased by SEMA3F, which led to cytoskeletal collapse and loss of cell motility in both cell types. Additionally, SEMA3E&F were able to inhibit vascular endothelial growth factor (VEGF)-induced sprouts in all three types of cells. Further, SEMA3E&F reduced the level of p-VEGFR2 and its downstream p-ERK in HemEC. These results demonstrate that SEMA3E&F inhibit IH cell proliferation and suppress the angiogenic activities of migration and sprout formation. SEMA3E&F may have therapeutic potential to treat or prevent growth of highly proliferative IH. - Highlights: • SEMA3E&F reduce actin stress fibers and induce cytoskeletal collapse in HemEC. • SEMA3E&F inhibit angiogenic activities of HemEC. • SEMA3E&F can interrupt the VEGF-A-VEGFR2-ERK signaling pathway in HemEC. • Plexin D1 and NRP2 are induced during HemSC/GLUT1{sup sel}-to-EC differentiation.

  4. MEK inhibition in non-small cell lung cancer.

    Science.gov (United States)

    Stinchcombe, Thomas E; Johnson, Gary L

    2014-11-01

    KRAS mutations are the most common mutations in non-small cell lung cancer (NSCLC) with adenocarcinoma histology. KRAS mutations result in the activation of the RAF-MEK-ERK pathway, and agents that target RAF-MEK-ERK pathways have been investigated in KRAS mutant NSCLC. The two agents furthest in development are selumetinib and trametinib. Trametinib has greater binding for the MEK1/2 allosteric site, and generally has superior pharmacokinetics. A randomized phase II trial of docetaxel with and without selumetinib revealed that the combination resulted numerically superior overall survival, and a statistically significant improvement in progression-free survival and objective response rate. However, a concerning rate of hospital admission, grade 3 or 4 neutropenia, and febrile neutropenia was observed with the combination. Trials have investigated MEK inhibitors as single agents and in combination with erlotinib, and the data do not support the further development. The activity of MEK inhibitors appears to be similar in patients with KRAS mutant and wild-type NSCLC suggesting KRAS mutation status is not a reliable biomarker for efficacy. It is possible that mutations of genes in addition to KRAS mutations impact the activity of MEK inhibitors, or specific subsets of KRAS mutations may be resistant or susceptible to MEK inhibition. Other potential explanations are gene amplifications, alternative RNA splicing of genes resulting in activation of their protein products, and deregulation of noncoding RNAs and consequent altered protein expression. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  5. Troglitazone inhibits cell growth and induces apoptosis of B-cell acute lymphoblastic leukemia cells with t(14;18).

    Science.gov (United States)

    Takenokuchi, M; Saigo, K; Nakamachi, Y; Kawano, S; Hashimoto, M; Fujioka, T; Koizumi, T; Tatsumi, E; Kumagai, S

    2006-01-01

    Peroxisome proliferator-activated receptor-gamma (PPARgamma), a member of the nuclear receptor superfamily, has been detected in several human leukemia cells. Recent studies reported that PPARgamma ligands inhibit cell proliferation and induce apoptosis in both normal and malignant B-lineage cells. We investigated the expression of PPARgamma and the effects of PPARgamma ligands on UTree-O2, Bay91 and 380, three B-cell acute lymphoblastic leukemia (B-ALL) cell lines with t(14;18), which show a poor prognosis, accompanying c-myc abnormality. Western blot analysis identified expression of PPARgamma protein and real-time PCR that of PPARgamma mRNA on the three cell lines. Troglitazone (TGZ), a synthetic PPARgamma ligand, inhibited cell growth in these cell lines in a dose-dependent manner, which was associated with G(1) cell cycle arrest and apoptosis. We also found this effect PPARgamma independent since PPARgamma antagonists failed to reverse this effect. We assessed the expression of c-myc, an apoptosis-regulatory gene, since c-myc abnormality was detected in most B-ALL cells with t(14;18). TGZ was found to dose-dependently downregulate the expression of c-myc mRNA and c-myc protein in the three cell lines. These results suggest that TGZ inhibits cell growth via induction of G(1) cell cycle arrest and apoptosis in these cell lines and that TGZ-induced apoptosis, at least in part, may be related to the downregulation of c-myc expression. Moreover, the downregulation of c-myc expression by TGZ may depend on a PPARgamma-independent mechanism. Further studies indicate that PPARgamma ligands may serve as a therapeutic agent in B-ALL with t(14;18).

  6. Releasing dentate nucleus cells from Purkinje cell inhibition generates output from the cerebrocerebellum.

    Directory of Open Access Journals (Sweden)

    Takahiro Ishikawa

    Full Text Available The cerebellum generates its vast amount of output to the cerebral cortex through the dentate nucleus (DN that is essential for precise limb movements in primates. Nuclear cells in DN generate burst activity prior to limb movement, and inactivation of DN results in cerebellar ataxia. The question is how DN cells become active under intensive inhibitory drive from Purkinje cells (PCs. There are two excitatory inputs to DN, mossy fiber and climbing fiber collaterals, but neither of them appears to have sufficient strength for generation of burst activity in DN. Therefore, we can assume two possible mechanisms: post-inhibitory rebound excitation and disinhibition. If rebound excitation works, phasic excitation of PCs and a concomitant inhibition of DN cells should precede the excitation of DN cells. On the other hand, if disinhibition plays a primary role, phasic suppression of PCs and activation of DN cells should be observed at the same timing. To examine these two hypotheses, we compared the activity patterns of PCs in the cerebrocerebellum and DN cells during step-tracking wrist movements in three Japanese monkeys. As a result, we found that the majority of wrist-movement-related PCs were suppressed prior to movement onset and the majority of wrist-movement-related DN cells showed concurrent burst activity without prior suppression. In a minority of PCs and DN cells, movement-related increases and decreases in activity, respectively, developed later. These activity patterns suggest that the initial burst activity in DN cells is generated by reduced inhibition from PCs, i.e., by disinhibition. Our results indicate that suppression of PCs, which has been considered secondary to facilitation, plays the primary role in generating outputs from DN. Our findings provide a new perspective on the mechanisms used by PCs to influence limb motor control and on the plastic changes that underlie motor learning in the cerebrocerebellum.

  7. Inhibition of oxidative stress-elicited AKT activation facilitates PPARγ agonist-mediated inhibition of stem cell character and tumor growth of liver cancer cells.

    Directory of Open Access Journals (Sweden)

    Lanlan Liu

    Full Text Available Emerging evidence suggests that tumor-initiating cells (TICs are the most malignant cell subpopulation in tumors because of their resistance to chemotherapy or radiation treatment. Targeting TICs may be a key innovation for cancer treatment. In this study, we found that PPARγ agonists inhibited the cancer stem cell-like phenotype and attenuated tumor growth of human hepatocellular carcinoma (HCC cells. Reactive oxygen species (ROS initiated by NOX2 upregulation were partially responsible for the inhibitory effects mediated by PPARγ agonists. However, PPARγ agonist-mediated ROS production significantly activated AKT, which in turn promoted TIC survival by limiting ROS generation. Inhibition of AKT, by either pharmacological inhibitors or AKT siRNA, significantly enhanced PPARγ agonist-mediated inhibition of cell proliferation and stem cell-like properties in HCC cells. Importantly, in nude mice inoculated with HCC Huh7 cells, we demonstrated a synergistic inhibitory effect of the PPARγ agonist rosiglitazone and the AKT inhibitor triciribine on tumor growth. In conclusion, we observed a negative feedback loop between oxidative stress and AKT hyperactivation in PPARγ agonist-mediated suppressive effects on HCCs. Combinatory application of an AKT inhibitor and a PPARγ agonist may provide a new strategy for inhibition of stem cell-like properties in HCCs and treatment of liver cancer.

  8. Uptake of 14C-labelled chloroquine and an 125I-labelled chloroquine analogue in some polypeptide hormone producing cell systems

    International Nuclear Information System (INIS)

    Dencker, L.; Lindquist, N.G.; Tjaelve, H.

    1976-01-01

    After the injection of 14 C-labelled chloroquine and the 125 I-labelled chloroquine analogue 4-(3 1 -dimethylaminopropylamino)-7-iodoquinoline [ 125 I]DAPQ into mice, rats and a monkey the distribution of the radioactivity was studied by autoradiographical methods. A high and persistent uptake occurred in some endocrine cell systems, such as the pancreatic islets, the hypophysis, the adrenal medulla and the thyroid (in cells that were probably identical with the parafollicular cells). The melanin-containing tissues were the only ones which showed a higher uptake and retention of radioactivity. The above mentioned endocrine cells and the melanocytes have a common embryological origin and common morphological and cytochemical characteristics. They have been called the APUD (Amine Precursor Uptake and Decarboxylation)-cell series. It is proposed that the polypeptide hormone producing cells and the melanocytes may use a similar mechanism for accumulating chloroquine and (as shown earlier) also some other drugs such as nicotine, alprenolol, local anesthetics and atropine. These drugs however, accumulate stronger within the melanocytes and become bound to the melanin for a long time. The ability to accumulate these drugs may be considered another characteristic of the APUD-cell series. (author)

  9. Recovery from inhibition of transcription in γ-irradiated Euglena cells

    International Nuclear Information System (INIS)

    Tsushimoto, G.; Kikuchi, T.; Ishida, M.R.

    1982-01-01

    Transcriptional activity was inhibited with low doses of γ-irradiation which did not cause the death of cells, but induced the delay of cell division in the unicellular alga Euglena. The incorporation of [ 14 C]uracil into cells was inhibited to about 50% of non-irradiated cells immediately after 3 krad irradiation. The suppressed transcriptional activity was gradually recovered after irradiation. At about 12 h post-irradiation, the rate of incorporation of [ 14 C]uracil recovered to that of non-irradiated cells. The synthesis of ribosomal RNA was inhibited immediately after 3 krad irradiation, but it recovered within 12 h after irradiation. The synthesis of cytosol ribosomal RNA precursor was more strongly inhibited than that of other cytosol ribosomal RNAs. The synthesis of cytoplasmic organelle ribosomal RNA was also inhibited and recovered after 3 krad irradiation. (Auth.)

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2014-04-18

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

  11. Effect of dicycloplatin, a novel platinum chemotherapeutical drug, on inhibiting cell growth and inducing cell apoptosis.

    Directory of Open Access Journals (Sweden)

    Guang-quan Li

    Full Text Available Dicycloplatin, a new supramolecular platinum-based antitumor drug, has been approved by the State Food and Administration (SFDA of China. In this study, we investigated the anticancer activity of dicycloplatin in cancer cells and signaling pathways involved in dicycloplatin-induced apoptosis. Dicycloplatin inhibited the proliferation of cancer cells and increased the percentage of apoptosis in a concentration-dependent manner. Besides, some apoptosis related events were observed after treatment with dicycloplatin, including increase of reactive oxygen species (ROS, collapse of mitochondrial membrane potential (Δψm, release of cytochrome c from the mitochondria to the cytosol, upregulation of p53, which were accompanied by activation of caspase-9, caspase-3, caspase-8, and poly (ADP-ribose polymerase cleavage in a concentration-dependent manner. The role of apoptosis in dicycloplatin-mediated cell death was further confirmed by the concomitant treatment with caspase-8 or caspase-9 inhibitors, which inhibited apoptosis and PARP cleavage. Intracellular glutathione (GSH was also found to inhibit the cytotoxic effect of dicycloplatin. In conclusion, these findings suggest that dicycloplatin induces apoptosis through ROS stress-mediated death receptor pathway and mitochondrial pathway which is similar to carboplatin.

  12. Inhibition by anandamide of 6-hydroxydopamine-induced cell death in PC12 cells.

    LENUS (Irish Health Repository)

    Mnich, Katarzyna

    2010-01-01

    6-hydroxydopamine (6-OHDA) is a selective neurotoxin that is widely used to investigate cell death and protective strategies in models of Parkinson\\'s disease. Here, we investigated the effects of the endogenous cannabinoid, anandamide, on 6-OHDA-induced toxicity in rat adrenal phaeochromocytoma PC12 cells. Morphological analysis and caspase-3 activity assay revealed that anandamide inhibited 6-OHDA-induced apoptosis. The protection was not affected by antagonists of either cannabinoid receptors (CB(1) or CB(2)) or the vanilloid receptor TRPV1. Anandamide-dependent protection was reduced by pretreatment with LY294002 (inhibitor of phosphatidylinositol 3-kinase, PI3K) and unaffected by U0126 (inhibitor of extracellularly-regulated kinase). Interestingly, phosphorylation of c-Jun-NH2-terminal kinase (JNK) in cells exposed to 6-OHDA was strongly reduced by anandamide pre-treatment. Furthermore, 6-OHDA induced c-Jun activation and increased Bim expression, both of which were inhibited by anandamide. Together, these data demonstrate antiapoptotic effects of anandamide and also suggest a role for activation of PI3K and inhibition of JNK signalling in anandamide-mediated protection against 6-OHDA.

  13. Fucosterol activates the insulin signaling pathway in insulin resistant HepG2 cells via inhibiting PTP1B.

    Science.gov (United States)

    Jung, Hyun Ah; Bhakta, Himanshu Kumar; Min, Byung-Sun; Choi, Jae Sue

    2016-10-01

    Insulin resistance is a characteristic feature of type 2 diabetes mellitus (T2DM) and is characterized by defects in insulin signaling. This study investigated the modulatory effects of fucosterol on the insulin signaling pathway in insulin-resistant HepG2 cells by inhibiting protein tyrosine phosphatase 1B (PTP1B). In addition, molecular docking simulation studies were performed to predict binding energies, the specific binding site of fucosterol to PTP1B, and to identify interacting residues using Autodock 4.2 software. Glucose uptake was determined using a fluorescent D-glucose analogue and the glucose tracer 2-[N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl) amino]-2-deoxyglucose, and the signaling pathway was detected by Western blot analysis. We found that fucosterol enhanced insulin-provoked glucose uptake and conjointly decreased PTP1B expression level in insulin-resistant HepG2 cells. Moreover, fucosterol significantly reduced insulin-stimulated serine (Ser307) phosphorylation of insulin receptor substrate 1 (IRS1) and increased phosphorylation of Akt, phosphatidylinositol-3-kinase, and extracellular signal- regulated kinase 1 at concentrations of 12.5, 25, and 50 µM in insulin-resistant HepG2 cells. Fucosterol inhibited caspase-3 activation and nuclear factor kappa B in insulin-resistant hepatocytes. These results suggest that fucosterol stimulates glucose uptake and improves insulin resistance by downregulating expression of PTP1B and activating the insulin signaling pathway. Thus, fucosterol has potential for development as an anti-diabetic agent.

  14. Antioxidant Properties and PC12 Cell Protective Effects of a Novel Curcumin Analogue (2E,6E-2,6-Bis(3,5- dimethoxybenzylidenecyclohexanone (MCH

    Directory of Open Access Journals (Sweden)

    Gui-Zhen Ao

    2014-03-01

    Full Text Available The antioxidative properties of a novel curcumin analogue (2E,6E-2,6-bis(3,5-dimethoxybenzylidenecyclohexanone (MCH were assessed by several in vitro models, including superoxide anion, hydroxyl radical and 1,1-diphenyl-2-picrylhydrazyl (DPPH radical scavenging and PC12 cell protection from H2O2 damage. MCH displayed superior O2•− quenching abilities compared to curcumin and vitamin C. In vitro stability of MCH was also improved compared with curcumin. Exposure of PC12 cells to 150 µM H2O2 caused a decrease of antioxidant enzyme activities, glutathione (GSH loss, an increase in malondialdehyde (MDA level, and leakage of lactate dehydrogenase (LDH, cell apoptosis and reduction in cell viability. Pretreatment of the cells with MCH at 0.63–5.00 µM before H2O2 exposure significantly attenuated those changes in a dose-dependent manner. MCH enhanced cellular expression of transcription factor NF-E2-related factor 2 (Nrf2 at the transcriptional level. Moreover, MCH could mitigate intracellular accumulation of reactive oxygen species (ROS, the loss of mitochondrial membrane potential (MMP, and the increase of cleaved caspase-3 activity induced by H2O2. These results show that MCH protects PC12 cells from H2O2 injury by modulating endogenous antioxidant enzymes, scavenging ROS, activating the Nrf2 cytoprotective pathway and prevention of apoptosis.

  15. 1,8-cineole inhibits both proliferation and elongation of BY-2 cultured tobacco cells.

    Science.gov (United States)

    Yoshimura, Hiroko; Sawai, Yu; Tamotsu, Satoshi; Sakai, Atsushi

    2011-03-01

    Volatile monoterpenes such as 1,8-cineole inhibit the growth of Brassica campestris seedlings in a dose-dependent manner, and the growth-inhibitory effects are more severe for roots than hypocotyls. The preferential inhibition of root growth may be explained if the compounds inhibit cell proliferation more severely than cell elongation because root growth requires both elongation and proliferation of the constituent cells, whereas hypocotyl growth depends exclusively on elongation of existing cells. In order to examine this possibility, BY-2 suspension-cultured tobacco (Nicotiana tabacum) cells were treated with 1,8-cineole, and the inhibitory effects on cell proliferation and on cell elongation were assessed quantitatively. Treatment with 1,8-cineole lowered both the mitotic index and elongation of the cells in a dose-dependent manner, and the half-maximal inhibitory concentration (IC₅₀) for cell elongation was lower than that for cell proliferation. Moreover, 1,8-cineole also inhibited starch synthesis, with IC₅₀ lower than that for cell proliferation. Thus, the inhibitory effects of 1,8-cineole were not specific to cell proliferation; rather, 1,8-cineole seemed inhibitory to a variety of physiological activities when it was in direct contact with target cells. Based on these results, possible mechanisms for the mode of action of 1,8-cineole and for its preferential inhibition on root growth are discussed.

  16. Advanced Glycation End Products Inhibit the Proliferation of Human Umbilical Vein Endothelial Cells by Inhibiting Cathepsin D

    Directory of Open Access Journals (Sweden)

    Yuan Li

    2017-02-01

    Full Text Available We aimed to investigate the effect of advanced glycation end products (AGEs on the proliferation and migration ability of human umbilical vein endothelial cells (HUVECs. Cell proliferation was detected by methyl thiazolyl tetrazolium (MTT assay, real-time cell analyzer and 5-Ethynyl-2′-deoxyuridine (EdU staining. Cell migration was detected by wound-healing and transwell assay. AGEs significantly inhibited the proliferation and migration of HUVECs in a time-and dose-dependent way. Western blotting revealed that AGEs dramatically increased the expression of microtubule-associated protein 1 light chain 3 (LC3 II/I and p62. Immunofluorescence of p62 and acridine orange staining revealed that AGEs significantly increased the expression of p62 and the accumulation of autophagic vacuoles, respectively. Chloroquine (CQ could further promote the expression of LC3 II/I and p62, increase the accumulation of autophagic vacuoles and promote cell injury induced by AGEs. In addition, AGEs reduced cathepsin D (CTSD expression in a time-dependent way. Overexpression of wild-type CTSD significantly decreased the ratio of LC 3 II/I as well as p62 accumulation induced by AGEs, but overexpression of catalytically inactive mutant CTSD had no such effects. Only overexpression of wild-type CTSD could restore the proliferation of HUVECs inhibited by AGEs. However, overexpression of both wild-type CTSD and catalytically inactive mutant CTSD could promote the migration of HUVECs inhibited by AGEs. Collectively, our study found that AGEs inhibited the proliferation and migration in HUVECs and promoted autophagic flux, which in turn played a protective role against AGEs-induced cell injury. CTSD, in need of its catalytic activity, may promote proliferation in AGEs-treated HUVECs independent of the autophagy-lysosome pathway. Meanwhile, CTSD could improve the migration of AGEs-treated HUVECs regardless of its enzymatic activity.

  17. Advanced Glycation End Products Inhibit the Proliferation of Human Umbilical Vein Endothelial Cells by Inhibiting Cathepsin D.

    Science.gov (United States)

    Li, Yuan; Chang, Ye; Ye, Ning; Dai, Dongxue; Chen, Yintao; Zhang, Naijin; Sun, Guozhe; Sun, Yingxian

    2017-02-17

    We aimed to investigate the effect of advanced glycation end products (AGEs) on the proliferation and migration ability of human umbilical vein endothelial cells (HUVECs). Cell proliferation was detected by methyl thiazolyl tetrazolium (MTT) assay, real-time cell analyzer and 5-Ethynyl-2'-deoxyuridine (EdU) staining. Cell migration was detected by wound-healing and transwell assay. AGEs significantly inhibited the proliferation and migration of HUVECs in a time-and dose-dependent way. Western blotting revealed that AGEs dramatically increased the expression of microtubule-associated protein 1 light chain 3 (LC3) II/I and p62. Immunofluorescence of p62 and acridine orange staining revealed that AGEs significantly increased the expression of p62 and the accumulation of autophagic vacuoles, respectively. Chloroquine (CQ) could further promote the expression of LC3 II/I and p62, increase the accumulation of autophagic vacuoles and promote cell injury induced by AGEs. In addition, AGEs reduced cathepsin D (CTSD) expression in a time-dependent way. Overexpression of wild-type CTSD significantly decreased the ratio of LC 3 II/I as well as p62 accumulation induced by AGEs, but overexpression of catalytically inactive mutant CTSD had no such effects. Only overexpression of wild-type CTSD could restore the proliferation of HUVECs inhibited by AGEs. However, overexpression of both wild-type CTSD and catalytically inactive mutant CTSD could promote the migration of HUVECs inhibited by AGEs. Collectively, our study found that AGEs inhibited the proliferation and migration in HUVECs and promoted autophagic flux, which in turn played a protective role against AGEs-induced cell injury. CTSD, in need of its catalytic activity, may promote proliferation in AGEs-treated HUVECs independent of the autophagy-lysosome pathway. Meanwhile, CTSD could improve the migration of AGEs-treated HUVECs regardless of its enzymatic activity.

  18. Thymoquinone suppresses metastasis of melanoma cells by inhibition of NLRP3 inflammasome

    Energy Technology Data Exchange (ETDEWEB)

    Ahmad, Israr; Muneer, Kashiff M.; Tamimi, Iman A.; Chang, Michelle E.; Ata, Muhammad O. [Department of Dermatology and Skin Diseases Research Center, University of Alabama at Birmingham, AL (United States); Yusuf, Nabiha, E-mail: nabiha@uab.edu [Department of Dermatology and Skin Diseases Research Center, University of Alabama at Birmingham, AL (United States); Veteran Affairs Medical Center, Birmingham, University of Alabama at Birmingham, AL (United States); Comprehensive Cancer Center, University of Alabama at Birmingham, AL (United States)

    2013-07-01

    The inflammasome is a multi-protein complex which when activated regulates caspase-1 activation and IL-1β and IL-18 secretion. The NLRP3 (NACHT, LRR, and pyrin domain-containing protein 3) inflammasome is constitutively assembled and activated in human melanoma cells. We have examined the inhibitory effect of thymoquinone (2-isopropyl-5-methylbenzo-1,4-quinone), a major ingredient of black seed obtained from the plant Nigella sativa on metastatic human (A375) and mouse (B16F10) melanoma cell lines. We have assessed whether thymoquinone inhibits metastasis of melanoma cells by targeting NLRP3 subunit of inflammasomes. Using an in vitro cell migration assay, we found that thymoquinone inhibited the migration of both human and mouse melanoma cells. The inhibitory effect of thymoquinone on metastasis was also observed in vivo in B16F10 mouse melanoma model. The inhibition of migration of melanoma cells by thymoquinone was accompanied by a decrease in expression of NLRP3 inflammasome resulting in decrease in proteolytic cleavage of caspase-1. Inactivation of caspase-1 by thymoquinone resulted in inhibition of IL-1β and IL-18. Treatment of mouse melanoma cells with thymoquinone also inhibited NF-κB activity. Furthermore, inhibition of reactive oxygen species (ROS) by thymoquinone resulted in partial inactivation of NLRP3 inflammasome. Thus, thymoquinone exerts its inhibitory effect on migration of human and mouse melanoma cells by inhibition of NLRP3 inflammasome. Thus, our results indicate that thymoquinone can be a potential immunotherapeutic agent not only as an adjuvant therapy for melanoma, but also, in the control and prevention of metastatic melanoma. - Highlights: • Thymoquinone causes inhibition of migration of melanoma cells. • Thymoquinone causes inhibition of metastasis in vivo. • Thymoquinone causes inhibition of migration by activation of NLRP3 inflammasome.

  19. Design, Synthesis and Cytotoxic Evaluation of o-Carboxamido Stilbene Analogues

    Directory of Open Access Journals (Sweden)

    Mohamad Nurul Azmi

    2013-11-01

    Full Text Available Resveratrol, a natural stilbene found in grapes and wines exhibits a wide range of pharmacological properties. Resveratrol is also known as a good chemopreventive agent for inhibiting carcinogenesis processes that target kinases, cyclooxygenases, ribonucleotide reductase and DNA polymerases. A total of 19 analogues with an amide moiety were synthesized and the cytotoxic effects of the analogues on a series of human cancer cell lines are reported. Three compounds 6d, 6i and 6n showed potent cytotoxicity against prostate cancer DU-145 (IC50 = 16.68 µM, colon cancer HT-29 (IC50 = 7.51 µM and breast cancer MCF-7 (IC50 = 21.24 µM, respectively, which are comparable with vinblastine. The resveratrol analogues were synthesized using the Heck method.

  20. Inhibition by derivatives of diguanidines of cell proliferation in Ehrlich ascites cells grown in cultures.

    Science.gov (United States)

    Alhonen-Hongisto, L; Pösö, H; Jänne, J

    1980-01-01

    The anti-proliferative effects of 1,1'-[(methylethanediylidene)dinitrilo]diguanidine [methylglyoxal bis(guanylhydrazone)] and 1,1'-[(metHYLETHANEDIYLIDENE)dinitrilo]bis-(3-aminoguaNIDINE) HAVE BEEN STUDIED IN Ehrlich ascites carcinoma cells grown in suspension cultures. Both compounds are potent inhibitors of S-adenosyl-L-methionine decarboxylase from the tumour cells. In the presence of putrescine (but not in its absence), the inhibition produced by 1,1'-[methylethanediylidene)dinitrilo]bis-(3-aminoguanadine) was apparently irreversible, as judged by persistent depression of the enzyme activity even after extensive dialysis. The two compounds produced similar increases in adenosylmethionine decarboxylase activity, which resulted from a striking stabilization of the enzyme in cells grown in the presence of the drugs. The inhibitory effect of the two diguanidine derivatives on the synthesis of DNA and protein became evident after an exposure of 4--8 h. At that time, the only change seen in tumour polyamines in cells grown in the presence of the inhibitors was an increase in cellular putrescine. To find out whether the compounds initially interfered with the energy production of the tumour cells, the cultures were grown in the presence of uniformly labelled glucose, and the formation of lactate, as well as the oxidation of the sugar into CO2, were measured. The activation of glycolysis upon dilution of the tumour cells with fresh medium and the subsequent formation of labelled CO2 were siliar in control cells and in cells exposed to methylglyoxal bis(buanylhydrazone), 1,1'-[(methylethanediylidene)dinitrilo]bis-(3-aminoguanidine) or diaminopropanol. Only a marginal decrease in the cellular content of ATP was found in cells exposed to the inhibitors for 24 h. The diguanidine-induced growth inhibition was fully reversed by low concentrations of exogenous polyamines. However, the possibility remained that the reversal by polyamines was due to a decrease of intracellular

  1. 3-Bromopyruvate inhibits cell proliferation and induces apoptosis in CD133+ population in human glioma.

    Science.gov (United States)

    Xu, Dong-Qiang; Tan, Xiao-Yu; Zhang, Bao-Wei; Wu, Tao; Liu, Ping; Sun, Shao-Jun; Cao, Yin-Guang

    2016-03-01

    The study was aimed to investigate the role of 3-bromopyruvate in inhibition of CD133+ U87 human glioma cell population growth. The results demonstrated that 3-bromopyruvate inhibited the viability of both CD133+ and parental cells derived from U87 human glioma cell line. However, the 3-bromopyruvate-induced inhibition in viability was more prominent in CD133+ cells at 10 μM concentration after 48 h. Treatment of CD133+ cells with 3-bromopyruvate caused reduction in cell population and cell size, membrane bubbling, and degradation of cell membranes. Hoechst 33258 staining showed condensation of chromatin material and fragmentation of DNA in treated CD133+ cells after 48 h. 3-Bromopyruvate inhibited the migration rate of CD133+ cells significantly compared to the parental cells. Flow cytometry revealed that exposure of CD133+ cells to 3-bromopyruvate increased the cell population in S phase from 24.5 to 37.9 % with increase in time from 12 to 48 h. In addition, 3-bromopyruvate significantly enhanced the expression of Bax and cleaved caspase 3 in CD133+ cells compared to the parental cells. Therefore, 3-bromopyruvate is a potent chemotherapeutic agent for the treatment of glioma by targeting stem cells selectively.

  2. Raman spectrum reveals Mesenchymal stem cells inhibiting HL60 cells growth

    Science.gov (United States)

    Su, Xin; Fang, Shaoyin; Zhang, Daosen; Zhang, Qinnan; Lu, Xiaoxu; Tian, Jindong; Fan, Jinping; Zhong, Liyun

    2017-04-01

    Though some research results reveals that Mesenchymal stem cells (MSCs) have the ability of inhibiting tumor cells proliferation, it remains controversial about the precise interaction mechanism during MSCs and tumor cells co-culture. In this study, combing Raman spectroscopic data and principle component analysis (PCA), the biochemical changes of MSCs or Human promyelocytic leukemia (HL60) cells during their co-culture were presented. The obtained results showed that some main Raman peaks of HL60 assigned to nucleic acids or proteins were greatly higher in intensity in the late stage of co-culture than those in the early stage of co-culture while they were still lower relative to the control group, implicating that the effect of MSCs inhibiting HL60 proliferation appeared in the early stage but gradually lost the inhibiting ability in the late stage of co-culture. Moreover, some other peaks of HL60 assigned to proteins were decreased in intensity in the early stage of co-culture relative to the control group but rebounded to the level similar to the control group in the late stage, showing that the content and structure changes of these proteins might be generated in the early stage but returned to the original state in the late stage of co-culture. As a result, in the early stage of MSCs-HL60 co-culture, along with the level of Akt phosphorylation of HL60 was lowered relative to its control group, the proliferation rate of HL60 cells was decreased. And in the late stage of co-culture, along with the level of Akt phosphorylation was rebounded, the reverse transfer of Raman peaks within 875-880 cm- 1 appeared, thus MSCs lost the ability to inhibit HL60 growth and HL60 proliferation was increased. In addition, it was observed that the peak at 811 cm- 1, which is a marker of RNA, was higher in intensity in the late stage than that in the control group, indicating that MSCs might be differentiated into myofibroblast-like MSCs. In addition, PCA results also exhibited

  3. Glucocorticoids inhibit the proliferation of IL-2-dependent T cell clones

    International Nuclear Information System (INIS)

    Fresno, M.; Redondo, J.M.; Lopez-Rivas, A.

    1986-01-01

    It has been shown that glucocorticoids inhibit mitogen or antigen-induced lymphocyte proliferation by decreasing the production of interleukin-2 (IL-2). They have studied the effect of dexamethasone (Dx) on the proliferation of IL-2-dependent T cell clones. They have found that preincubation of these clones with Dx inhibits ( 3 H) thymidine incorporation and cell proliferation in a dose-dependent manner (ID 50 % 5 x 10 -10 M). The inhibition of DNA synthesis by Dx was dependent on the concentration of IL-2. High concentration of IL-2 reversed completely this inhibition. The action of Dx seems to be mediated through the induction of a protein since the simultaneous presence of cycloheximide and Dx prevented the inhibitory effect of the latter. Moreover, dialyzed conditioned medium of Dx treated cells inhibited DNA synthesis by T cell clones. The biochemical characterization of this protein is in progress

  4. Cordycepin Induces Apoptosis and Inhibits Proliferation of Human Lung Cancer Cell Line H1975 via Inhibiting the Phosphorylation of EGFR

    Directory of Open Access Journals (Sweden)

    Zheng Wang

    2016-09-01

    Full Text Available Cordycepin is an active component of the traditional Chinese medicine Cordyceps sinensis and Cordyceps militaris with notable anticancer activity. Though the prominent inhibitory activity was reported in different kinds of cancer cell lines, the concrete mechanisms remain elusive. It was reported that cordycepin could be converted into tri-phosphates in vivo to confuse a number of enzymes and interfere the normal cell function. For the inhibitory mechanism of EGFR inhibitors and the structure similarity of ATP and tri-phosphated cordycepin, human lung cancer cell line H1975 was employed to investigate the inhibitory effect of cordycepin. The results showed that cordycepin could inhibit cell proliferation and induce apoptosis in a dose-dependent manner. Cell cycle analysis revealed that H1975 cells could be arrested at the G0/G1 phase after cordycepin treatment. The expression levels of apoptosis-related protein Caspase-3 and Bcl-2 and phosphorylated expression levels of EGFR, AKT and ERK1/2 were all decreased compared with the control group stimulated with EGF. However, the protein expression levels of proapoptotic protein Bax and cleaved caspase-3 were increased. These results implied that cordycepin could inhibit cell proliferation and induce apoptosis via the EGFR signaling pathway. Our results indicated that there was potential to seek a novel EGFR inhibitor from cordycepin and its chemical derivatives.

  5. Coniferyl aldehyde attenuates radiation enteropathy by inhibiting cell death and promoting endothelial cell function.

    Science.gov (United States)

    Jeong, Ye-Ji; Jung, Myung Gu; Son, Yeonghoon; Jang, Jun-Ho; Lee, Yoon-Jin; Kim, Sung-Ho; Ko, Young-Gyo; Lee, Yun-Sil; Lee, Hae-June

    2015-01-01

    Radiation enteropathy is a common complication in cancer patients. The aim of this study was to investigate whether radiation-induced intestinal injury could be alleviated by coniferyl aldehyde (CA), an HSF1-inducing agent that increases cellular HSP70 expression. We systemically administered CA to mice with radiation enteropathy following abdominal irradiation (IR) to demonstrate the protective effects of CA against radiation-induced gastrointestinal injury. CA clearly alleviated acute radiation-induced intestinal damage, as reflected by the histopathological data and it also attenuated sub-acute enteritis. CA prevented intestinal crypt cell death and protected the microvasculature in the lamina propria during the acute and sub-acute phases of damage. CA induced HSF1 and HSP70 expression in both intestinal epithelial cells and endothelial cells in vitro. Additionally, CA protected against not only the apoptotic cell death of both endothelial and epithelial cells but also the loss of endothelial cell function following IR, indicating that CA has beneficial effects on the intestine. Our results provide novel insight into the effects of CA and suggest its role as a therapeutic candidate for radiation-induced enteropathy due to its ability to promote rapid re-proliferation of the intestinal epithelium by the synergic effects of the inhibition of cell death and the promotion of endothelial cell function.

  6. Armet, a UPR-upregulated protein, inhibits cell proliferation and ER stress-induced cell death

    International Nuclear Information System (INIS)

    Apostolou, Andria; Shen Yuxian; Liang Yan; Luo Jun; Fang Shengyun

    2008-01-01

    The accumulation of misfolded proteins in the endoplasmic reticulum (ER) causes ER stress that initiates the unfolded protein response (UPR). UPR activates both adaptive and apoptotic pathways, which contribute differently to disease pathogenesis. To further understand the functional mechanisms of UPR, we identified 12 commonly UPR-upregulated genes by expression microarray analysis. Here, we describe characterization of Armet/MANF, one of the 12 genes whose function was not clear. We demonstrated that the Armet/MANF protein was upregulated by various forms of ER stress in several cell lines as well as by cerebral ischemia of rat. Armet/MANF was localized in the ER and Golgi and was also a secreted protein. Silencing Armet/MANF by siRNA oligos in HeLa cells rendered cells more susceptible to ER stress-induced death, but surprisingly increased cell proliferation and reduced cell size. Overexpression of Armet/MANF inhibited cell proliferation and improved cell viability under glucose-free conditions and tunicamycin treatment. Based on its inhibitory properties for both proliferation and cell death we have demonstrated, Armet is, thus, a novel secreted mediator of the adaptive pathway of UPR

  7. Dasatinib inhibits both osteoclast activation and prostate cancer PC-3 cell-induced osteoclast formation

    Science.gov (United States)

    Araujo, John C.; Poblenz, Ann; Corn, Paul G.; Parikh, Nila U.; Starbuck, Michael W.; Thompson, Jerry T.; Lee, Francis; Logothetis, Christopher J.; Darnay, Bryant G.

    2013-01-01

    Purpose Therapies to target prostate cancer bone metastases have only limited effects. New treatments are focused on the interaction between cancer cells, bone marrow cells and the bone matrix. Osteoclasts play an important role in the development of bone tumors caused by prostate cancer. Since Src kinase has been shown to be necessary for osteoclast function, we hypothesized that dasatinib, a Src family kinase inhibitor, would reduce osteoclast activity and prostate cancer (PC-3) cell-induced osteoclast formation. Results Dasatinib inhibited RANKL-induced osteoclast differentiation of bone marrow-derived monocytes with an EC50 of 7.5 nM. PC-3 cells, a human prostate cancer cell line, were able to differentiate RAW 264.7 cells, a murine monocytic cell line, into osteoclasts and dasatinib inhibited this differentiation. In addition, conditioned medium from PC-3 cell cultures was able to differentiate RAW 264.7 cells into osteoclasts and this too, was inhibited by dasatinib. Even the lowest concentration of dasatinib, 1.25 nmol, inhibited osteoclast differentiation by 29%. Moreover, dasatinib inhibited osteoclast activity by 58% as measured by collagen 1 release. Experimental design We performed in vitro experiments utilizing the Src family kinase inhibitor dasatinib to target osteoclast activation as a means of inhibiting prostate cancer bone metastases. Conclusion Dasatinib inhibits osteoclast differentiation of mouse primary bone marrow-derived monocytes and PC-3 cell-induced osteoclast differentiation. Dasatinib also inhibits osteoclast degradation activity. Inhibiting osteoclast differentiation and activity may be an effective targeted therapy in patients with prostate cancer bone metastases. PMID:19855158

  8. Na+ -K+ pump activity in rat peritoneal mast cells: inhibition by extracellular calcium

    DEFF Research Database (Denmark)

    Knudsen, Torben; Johansen, Torben

    1989-01-01

    1. Pure populations of rat peritoneal mast cells were used to study cellular potassium uptake. The radioactive potassium analogue, 86rubidium, was used as a tracer for potassium for measurements of the activity of the cellular potassium uptake process. 2. The ouabain-sensitive and the ouabain......-resistant potassium (86rubidium) uptake of mast cells incubated in the presence of calcium, 1 mmol l-1, were very low, 52 and 147 pmol per 10(6) cells min-1. 3. Calcium-deprivation of the cells uncovered a large capacity ouabain-sensitive potassium (86rubidium) uptake mechanism. The activity of the uptake mechanism...... was decreased by reintroduction of calcium into the cell suspension, and it was dependent on cellular energy metabolism, temperature and pH. 4. The potassium (86rubidium) uptake of mast cells incubated in a calcium-free medium occurs through an active and ouabain-sensitive mechanism that has the nature...

  9. Zoledronic acid inhibits pulmonary metastasis dissemination in a preclinical model of Ewing’s sarcoma via inhibition of cell migration

    International Nuclear Information System (INIS)

    Odri, Guillaume; Kim, Pui-Pui; Lamoureux, François; Charrier, Céline; Battaglia, Séverine; Amiaud, Jérôme; Heymann, Dominique; Gouin, François; Redini, Françoise

    2014-01-01

    Ewing’s sarcoma (ES) is the second most frequent primitive malignant bone tumor in adolescents with a very poor prognosis for high risk patients, mainly when lung metastases are detected (overall survival <15% at 5 years). Zoledronic acid (ZA) is a potent inhibitor of bone resorption which induces osteoclast apoptosis. Our previous studies showed a strong therapeutic potential of ZA as it inhibits ES cell growth in vitro and ES primary tumor growth in vivo in a mouse model developed in bone site. However, no data are available on lung metastasis. Therefore, the aim of this study was to determine the effect of ZA on ES cell invasion and metastatic properties. Invasion assays were performed in vitro in Boyden’s chambers covered with Matrigel. Matrix Metalloproteinase (MMP) activity was analyzed by zymography in ES cell culture supernatant. In vivo, a relevant model of spontaneous lung metastases which disseminate from primary ES tumor was induced by the orthotopic injection of 10 6 human ES cells in the tibia medullar cavity of nude mice. The effect of ZA (50 μg/kg, 3x/week) was studied over a 4-week period. Lung metastases were observed macroscopically at autopsy and analysed by histology. ZA induced a strong inhibition of ES cell invasion, probably due to down regulation of MMP-2 and −9 activities as analyzed by zymography. In vivo, ZA inhibits the dissemination of spontaneous lung metastases from a primary ES tumor but had no effect on the growth of established lung metastases. These results suggest that ZA could be used early in the treatment of ES to inhibit bone tumor growth but also to prevent the early metastatic events to the lungs

  10. Cell-surface expression of Hsp70 on hematopoietic cancer cells after inhibition of HDAC activity

    DEFF Research Database (Denmark)

    Jensen, Helle; Andresen, Lars; Hansen, Karen Aagaard

    Heat shock proteins (HSPs) are highly conserved molecules, which support folding of proteins under physiological conditions and mediate protection against lethal damage after various stress stimuli. Five HSP families exist defined by their molecular size (i.e. HSP100, HSP90, HSP70, HSP60, and the......Heat shock proteins (HSPs) are highly conserved molecules, which support folding of proteins under physiological conditions and mediate protection against lethal damage after various stress stimuli. Five HSP families exist defined by their molecular size (i.e. HSP100, HSP90, HSP70, HSP60...... clinically applied reagents, such as alkyl-lysophospholipides, chemotherapeutic agents, and anti-inflammatory reagents, have been found to enhance Hsp70 surface expression on cancer cells. We have found that inhibition of histone deacetylase (HDAC) activity leads to surface expression of Hsp70 on various...... hematopoietic cancer cells, an occurance that was not observed on naïve or activated peripheral blood cells. HDAC-inhibitor mediated Hsp70 surface expression was confined to the apoptotic Annexin V positive cells and blocked by inhibition of apoptosis. Other chemotherapeutic inducers of apoptosis...

  11. Ginger Phytochemicals Inhibit Cell Growth and Modulate Drug Resistance Factors in Docetaxel Resistant Prostate Cancer Cell.

    Science.gov (United States)

    Liu, Chi-Ming; Kao, Chiu-Li; Tseng, Yu-Ting; Lo, Yi-Ching; Chen, Chung-Yi

    2017-09-05

    Ginger has many bioactive compounds with pharmacological activities. However, few studies are known about these bioactive compounds activity in chemoresistant cells. The aim of the present study was to investigate the anticancer properties of ginger phytochemicals in docetaxel-resistant human prostate cancer cells in vitro. In this study, we isolated 6-gingerol, 10-gingerol, 4-shogaol, 6-shogaol, 10-shogaol, and 6-dehydrogingerdione from ginger. Further, the antiproliferation activity of these compounds was examined in docetaxel-resistant (PC3R) and sensitive (PC3) human prostate cancer cell lines. 6-gingerol, 10-gingerol, 6-shogaol, and 10-shogaol at the concentration of 100 μM significantly inhibited the proliferation in PC3R but 6-gingerol, 6-shogaol, and 10-shogaol displayed similar activity in PC3. The protein expression of multidrug resistance associated protein 1 (MRP1) and glutathione-S-transferase (GSTπ) is higher in PC3R than in PC3. In summary, we isolated the bioactive compounds from ginger. Our results showed that 6-gingerol, 10-gingerol, 6-shogaol, and 10-shogaol inhibit the proliferation of PC3R cells through the downregulation of MRP1 and GSTπ protein expression.

  12. Anthracyclines as radiosensitizers. A Cu(II) complex of a simpler analogue modifies DNA in Chinese Hamster V79 cells under low-dose γ radiation

    International Nuclear Information System (INIS)

    Saurabh Das; Mandal, P.C.

    2014-01-01

    Hydroxy-9,10-anthraquinones are structural analogues of anthracycline anticancer drugs showing similarity in physicochemical attributes, electrochemical behavior and biophysical interactions. 1,2-dihydroxy-9,10-anthraquinone (Q) and its complexes with Cu(II)/Ni(II) were studied for γ radiation induced modification of DNA in Chinese Hamster V79 cells. The amount of double stranded DNA remaining was ascertained by fluorometric analysis of DNA unwinding using ethidium bromide. Modification of double stranded DNA increased in the presence of Q and Cu(II)-Q when cells were irradiated (0-4.2 Gray). Ni(II)-Q was not that effective. Changing incubation time before recovery of DNA from cells there was evidence for DNA repair that was least for Cu(II)-Q treated cells. Minimum repair in case of Cu(II)-Q treated cells suggest the compound either assists radiation induced damage of agents responsible for repair or interacts with species like H 2 O 2 that assist in repair. Since a hydroxy-9,10-anthraquinone and its Cu(II) complex show radiosensitizing property, anthracyclines that contain a hydroxy-9,10-anthraquinone as the core moiety could also be tried as radiosensitizers in treating cancer. (author)

  13. Selected Phytochemicals and Culinary Plant Extracts Inhibit Fructose Uptake in Caco-2 Cells.

    Science.gov (United States)

    Lee, Yurim; Lim, Yeni; Kwon, Oran

    2015-09-18

    This study compared the ability of nine culinary plant extracts containing a wide array of phytochemicals to inhibit fructose uptake and then explored the involvement of intestinal fructose transporters and phytochemicals for selected samples. The chemical signature was characterized by high performance liquid chromatography with mass spectrometry. Inhibition of [(14)C]-fructose uptake was tested by using human intestinal Caco-2 cells. Then, the relative contribution of the two apical-facing intestinal fructose transporters, GLUT2 and GLUT5, and the signature components for fructose uptake inhibition was confirmed in naive, phloretin-treated and forskolin-treated Caco-2 cells. HPLC/MS analysis of the chemical signature revealed that guava leaf contained quercetin and catechin, and turmeric contained curcumin, bisdemethoxycurcumin and dimethoxycurcumin. Similar inhibition of fructose uptake (by ~50%) was observed with guava leaf and turmeric in Caco-2 cells, but with a higher contribution of GLUT2 for turmeric and that of GLUT5 for guava leaf. The data suggested that, in turmeric, demethoxycurcumin specifically contributed to GLUT2-mediated fructose uptake inhibition, and curcumin did the same to GLUT5-mediated fructose uptake inhibition, but GLUT2 inhibition was more potent. By contrast, in guava leaf, catechin specifically contributed to GLUT5-mediated fructose uptake inhibition, and quercetin affected both GLUT5- and GLUT2-mediated fructose uptake inhibition, resulting in the higher contribution of GLUT5. These results suggest that demethoxycurcumin is an important contributor to GLUT2-mediated fructose uptake inhibition for turmeric extract, and catechin is the same to GLUT5-mediated fructose uptake inhibition for guava leaf extract. Quercetin, curcumin and bisdemethoxycurcumin contributed to both GLUT5- and GLUT2-mediated fructose uptake inhibition, but the contribution to GLUT5 inhibition was higher than the contribution to GLUT2 inhibition.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2007-04-15

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

  15. Inhibition of host cell protein synthesis by UV-inactivated poliovirus

    International Nuclear Information System (INIS)

    Helentjaris, T.; Ehrenfeld, E.

    1977-01-01

    The ability of poliovirus that was irradiated with UV light at energies up to 2,160 ergs/mm 2 to subsequently inhibit host cell protein synthesis was measured. The inactivation of the host cell shutoff function followed one-hit kinetics. Increasing irradiation did not affect the rate of inhibition until the multiplicity of infection after irradiation was reduced to approximately 1 PFU/cell. At higher functional multiplicities, the rate was unchanged, but an increasing lag before the onset of inhibition was observed with increasing irradiation. The energy levels required to inactivate virus-induced inhibition of host cell protein synthesis suggest that damage to virus RNA rather than to virus capsid proteins is responsible for the loss of function. When the inactivation of host cell shutoff was compared with the inactivation of other viral functions by UV irradiation, it correlated exactly with the loss of infectivity but not with other viral functions measured. Guanidine treatment, which prevents detectable viral RNA and protein synthesis, completely inhibited host cell shutoff by low multiplicities of unirradiated virus infection but not higher multiplicities. When a high multiplicity of virus was first reduced to a low titer by irradiation, host cell shutoff was still evident in the presence of guanidine. The results demonstrate that the complete inhibition of host cell protein synthesis can be accomplished by one infectious viral genome per cell

  16. Pulmonary surfactant and its components inhibit secretion of phosphatidylcholine from cultured rat alveolar type II cells

    International Nuclear Information System (INIS)

    Dobbs, L.G.; Wright, J.R.; Hawgood, S.; Gonzalez, R.; Venstrom, K.; Nellenbogen, J.

    1987-01-01

    Pulmonary surfactant is synthesized and secreted by alveolar type II cells. Radioactive phosphatidylcholine has been used as a marker for surfactant secretion. The authors report findings that suggest that surfactant inhibits secretion of 3 H-labeled phosphatidylcholine by cultured rat type II cells. The lipid components and the surfactant protein group of M/sub r/ 26,000-36,000 (SP 26-36) inhibit secretion to different extents. Surfactant lipids do not completely inhibit release; in concentrations of 100 μg/ml, lipids inhibit stimulated secretion by 40%. SP 26-36 inhibits release with an EC 50 of 0.1 μg/ml. At concentrations of 1.0 μg/ml, SP 26-36 inhibits basal secretion and reduces to basal levels secretion stimulated by terbutaline, phorbol 12-myristate 13-acetate, and the ionophore A23187. The inhibitory effect of SP 26-36 can be blocked by washing type II cells after adding SP 26-36, by heating the proteins to 100 0 C for 10 min, by adding antiserum specific to SP 26-36, or by incubating cells in the presence of 0.2 mM EGTA. SP 26-36 isolated from canine and human sources also inhibits phosphatidylcholine release from rat type II cells. Neither type I collagen nor serum apolipoprotein A-1 inhibits secretion. These findings are compatible with the hypothesis that surfactant secretion is under feedback regulatory control

  17. Inhibition of host cell translation elongation by Legionella pneumophila blocks the host cell unfolded protein response.

    Science.gov (United States)

    Hempstead, Andrew D; Isberg, Ralph R

    2015-12-08

    Cells of the innate immune system recognize bacterial pathogens by detecting common microbial patterns as well as pathogen-specific activities. One system that responds to these stimuli is the IRE1 branch of the unfolded protein response (UPR), a sensor of endoplasmic reticulum (ER) stress. Activation of IRE1, in the context of Toll-like receptor (TLR) signaling, induces strong proinflammatory cytokine induction. We show here that Legionella pneumophila, an intravacuolar pathogen that replicates in an ER-associated compartment, blocks activation of the IRE1 pathway despite presenting pathogen products that stimulate this response. L. pneumophila TLR ligands induced the splicing of mRNA encoding XBP1s, the main target of IRE1 activity. L. pneumophila was able to inhibit both chemical and bacterial induction of XBP1 splicing via bacterial translocated proteins that interfere with host protein translation. A strain lacking five translocated translation elongation inhibitors was unable to block XBP1 splicing, but this could be rescued by expression of a single such inhibitor, consistent with limitation of the response by translation elongation inhibitors. Chemical inhibition of translation elongation blocked pattern recognition receptor-mediated XBP1 splicing, mimicking the effects of the bacterial translation inhibitors. In contrast, host cell-promoted inhibition of translation initiation in response to the pathogen was ineffective in blocking XBP1 splicing, demonstrating the need for the elongation inhibitors for protection from the UPR. The inhibition of host translation elongation may be a common strategy used by pathogens to limit the innate immune response by interfering with signaling via the UPR.

  18. Molecular Mechanisms by Which a Fucus vesiculosus Extract Mediates Cell Cycle Inhibition and Cell Death in Pancreatic Cancer Cells

    Directory of Open Access Journals (Sweden)

    Ulf Geisen

    2015-07-01

    Full Text Available Pancreatic cancer is one of the most aggressive cancer entities, with an extremely poor 5-year survival rate. Therefore, novel therapeutic agents with specific modes of action are urgently needed. Marine organisms represent a promising source to identify new pharmacologically active substances. Secondary metabolites derived from marine algae are of particular interest. The present work describes cellular and molecular mechanisms induced by an HPLC-fractionated, hydrophilic extract derived from the Baltic brown seaweed Fucus vesiculosus (Fv1. Treatment with Fv1 resulted in a strong inhibition of viability in various pancreatic cancer cell lines. This extract inhibited the cell cycle of proliferating cells due to the up-regulation of cell cycle inhibitors, shown on the mRNA (microarray data and protein level. As a result, cells were dying in a caspase-independent manner. Experiments with non-dividing cells showed that proliferation is a prerequisite for the effectiveness of Fv1. Importantly, Fv1 showed low cytotoxic activity against non-malignant resting T cells and terminally differentiated cells like erythrocytes. Interestingly, accelerated killing effects were observed in combination with inhibitors of autophagy. Our in vitro data suggest that Fv1 may represent a promising new agent that deserves further development towards clinical application.

  19. E-cadherin homophilic ligation inhibits cell growth and epidermal growth factor receptor signaling independently of other cell interactions

    DEFF Research Database (Denmark)

    Perrais, Michaël; Chen, Xiao; Perez-Moreno, Mirna

    2007-01-01

    growth inhibitory signals. To address this question, we have selectively formed E-cadherin homophilic bonds at the cell surface of isolated epithelial cells by using functionally active recombinant E-cadherin protein attached to microspheres. We find that E-cadherin ligation alone reduces the frequency...... of cells entering the S phase, demonstrating that E-cadherin ligation directly transduces growth inhibitory signals. E-cadherin binding to beta-catenin is required for cell growth inhibition, but beta-catenin/T-cell factor transcriptional activity is not involved in growth inhibition resulting from...... homophilic binding. Neither E-cadherin binding to p120-catenin nor beta-catenin binding to alpha-catenin, and thereby the actin cytoskeleton, is required for growth inhibition. E-cadherin ligation also inhibits epidermal growth factor (EGF) receptor-mediated growth signaling by a beta...

  20. Prolyl oligopeptidase inhibition-induced growth arrest of human gastric cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, Kanayo [Laboratory of Cell Biology, Osaka University of Pharmaceutical Sciences, 4-20-1 Nasahara, Takatsuki, Osaka 569-1094 (Japan); Sakaguchi, Minoru, E-mail: sakaguti@gly.oups.ac.jp [Laboratory of Cell Biology, Osaka University of Pharmaceutical Sciences, 4-20-1 Nasahara, Takatsuki, Osaka 569-1094 (Japan); Tanaka, Satoshi [Laboratory of Cell Biology, Osaka University of Pharmaceutical Sciences, 4-20-1 Nasahara, Takatsuki, Osaka 569-1094 (Japan); Yoshimoto, Tadashi [Department of Life Science, Setsunan University, 17-8 Ikeda-Nakamachi, Neyagawa, Osaka 572-8508 (Japan); Takaoka, Masanori [Laboratory of Cell Biology, Osaka University of Pharmaceutical Sciences, 4-20-1 Nasahara, Takatsuki, Osaka 569-1094 (Japan)

    2014-01-03

    Highlights: •We examined the effects of prolyl oligopeptidase (POP) inhibition on p53 null gastric cancer cell growth. •POP inhibition-induced cell growth suppression was associated with an increase in a quiescent G{sub 0} state. •POP might regulate the exit from and/or reentry into the cell cycle. -- Abstract: Prolyl oligopeptidase (POP) is a serine endopeptidase that hydrolyzes post-proline peptide bonds in peptides that are <30 amino acids in length. We recently reported that POP inhibition suppressed the growth of human neuroblastoma cells. The growth suppression was associated with pronounced G{sub 0}/G{sub 1} cell cycle arrest and increased levels of the CDK inhibitor p27{sup kip1} and the tumor suppressor p53. In this study, we investigated the mechanism of POP inhibition-induced cell growth arrest using a human gastric cancer cell line, KATO III cells, which had a p53 gene deletion. POP specific inhibitors, 3-((4-[2-(E)-styrylphenoxy]butanoyl)-L-4-hydroxyprolyl)-thiazolidine (SUAM-14746) and benzyloxycarbonyl-thioprolyl-thioprolinal, or RNAi-mediated POP knockdown inhibited the growth of KATO III cells irrespective of their p53 status. SUAM-14746-induced growth inhibition was associated with G{sub 0}/G{sub 1} cell cycle phase arrest and increased levels of p27{sup kip1} in the nuclei and the pRb2/p130 protein expression. Moreover, SUAM-14746-mediated cell cycle arrest of KATO III cells was associated with an increase in the quiescent G{sub 0} state, defined by low level staining for the proliferation marker, Ki-67. These results indicate that POP may be a positive regulator of cell cycle progression by regulating the exit from and/or reentry into the cell cycle by KATO III cells.

  1. Nelfinavir augments proteasome inhibition by bortezomib in myeloma cells and overcomes bortezomib and carfilzomib resistance

    International Nuclear Information System (INIS)

    Kraus, M; Bader, J; Overkleeft, H; Driessen, C

    2013-01-01

    HIV protease inhibitors (HIV-PI) are oral drugs for HIV treatment. HIV-PI have antitumor activity via induction of ER-stress, inhibition of phospho-AKT (p-AKT) and the proteasome, suggesting antimyeloma activity. We characterize the effects of all approved HIV-PI on myeloma cells. HIV-PI were compared regarding cytotoxicity, proteasome activity, ER-stress induction and AKT phosphorylation using myeloma cells in vitro. Nelfinavir is the HIV-PI with highest cytotoxic activity against primary myeloma cells and with an IC 50 near therapeutic drug blood levels (8–14 μM), irrespective of bortezomib sensitivity. Only nelfinavir inhibited intracellular proteasome activity in situ at drug concentrations <40 μℳ. Ritonavir, saquinavir and lopinavir inhibited p-AKT comparable to nelfinavir, and showed similar synergistic cytotoxicity with bortezomib against bortezomib-sensitive cells. Nelfinavir had superior synergistic activity with bortezomib/carfilzomib in particular against bortezomib/carfilzomib-resistant myeloma cells. It inhibited not only the proteasomal β1/β5 active sites, similar to bortezomib/carfilzomib, but in addition the β2 proteasome activity not targeted by bortezomib/carfilzomib. Additional inhibition of β2 proteasome activity is known to sensitize cells for bortezomib and carfilzomib. Nelfinavir has unique proteasome inhibiting activity in particular on the bortezomib/carfilzomib-insensitive tryptic (β2) proteasome activity in intact myeloma cells, and is active against bortezomib/carfilzomib-resistant myeloma cells in vitro

  2. Sites of inhibition of mitochondrial electron transport in macrophage-injured neoplastic cells.

    Science.gov (United States)

    Granger, D L; Lehninger, A L

    1982-11-01

    Previous work has shown that injury of neoplastic cells by cytotoxic macrophages (CM) in cell culture is accompanied by inhibition of mitochondrial respiration. We have investigated the nature of this inhibition by studying mitochondrial respiration in CM-injured leukemia L1210 cells permeabilized with digitonin. CM-induced injury affects the mitochondrial respiratory chain proper. Complex I (NADH-coenzyme Q reductase) and complex II (succinate-coenzyme Q reductase) are markedly inhibited. In addition a minor inhibition of cytochrome oxidase was found. Electron transport from alpha-glycerophosphate through the respiratory chain to oxygen is unaffected and permeabilized CM-injured L1210 cells oxidizing this substrate exhibit acceptor control. However, glycerophosphate shuttle activity was found not to occur within CM-injured or uninjured L1210 cells in culture hence, alpha-glycerophosphate is apparently unavailable for mitochondrial oxidation in the intact cell. It is concluded that the failure of respiration of intact neoplastic cells injured by CM is caused by the nearly complete inhibition of complexes I and II of the mitochondrial electron transport chain. The time courses of CM-induced electron transport inhibition and arrest of L1210 cell division are examined and the possible relationship between these phenomena is discussed.

  3. TNF-α Regulates Mast Cell Functions by Inhibiting Cell Degranulation

    Directory of Open Access Journals (Sweden)

    Yuwei Gao

    2017-11-01

    Full Text Available Background/Aims: The aim of this study was to investigate the involvement of inducible co-stimulatory ligand (ICOSL expression in stimulation of mast cells (MCs by TNF-α and the ability of TNF-α stimulation of MCs to influence CD4+ T cell differentiation and function. The mechanisms underlying TNF-α stimulation of MCs were also explored. Methods: Mast cells and CD4+ T cells were prepared from C57BL/6 mice (aged 6–8 weeks. ICOSL expression by MCs was measured by real-time PCR and flow cytometry, and levels of IL-4, IL-10 and IFN-γ were measured by ELISA. Results: ICOSL expression by MCs was increased by TNF-α stimulation, and resulted in interaction with CD4+ T cells. The IL-4 and IL-10 levels in the co-culture system increased, while IFN-γ levels decreased. Furthermore, CD4+CD25+Foxp3+ T cell proliferation was induced by co-culture with TNF-α-stimulated MCs. The mechanism by which TNF-α stimulated MCs was dependent on the activation of the MAPK signaling pathway. Conclusion: TNF-α upregulated the expression of ICOSL on mast cells via a mechanism that is dependent on MAPK phosphorylation. TNF-α-treated MCs promoted the differentiation of regulatory T cells and induced a shift in cytokine expression from a Th1 to a Th2 profile by up-regulation ICOSL expression and inhibition of MC degranulation. Our study reveals a novel mechanism by which mast cells regulate T cell function.

  4. Sulforaphane inhibits osteoclast differentiation by suppressing the cell-cell fusion molecules DC-STAMP and OC-STAMP

    International Nuclear Information System (INIS)

    Takagi, Tomohiro; Inoue, Hirofumi; Takahashi, Nobuyuki; Katsumata-Tsuboi, Rie; Uehara, Mariko

    2017-01-01

    Sulforaphane (SFN), a kind of isothiocyanate, is derived from broccoli sprouts. It has anti-tumor, anti-inflammatory, and anti-oxidation activity. The molecular function of SFN in the inhibition of osteoclast differentiation is not well-documented. In this study, we assessed the effect of SFN on osteoclast differentiation in vitro. SFN inhibited osteoclast differentiation in both bone marrow cells and RAW264.7 cells. Key molecules involved in the inhibitory effects of SFN on osteoclast differentiation were determined using a microarray analysis, which showed that SFN inhibits osteoclast-associated genes, such as osteoclast-associated receptor (OSCAR), nuclear factor of activated T cells cytoplasmic-1, tartrate-resistant acid phosphatase, and cathepsin K. Moreover, the mRNA expression levels of the cell-cell fusion molecules dendritic cell specific transmembrane protein (DC-STAMP) and osteoclast stimulatory transmembrane protein (OC-STAMP) were strongly suppressed in cells treated with SFN. Furthermore, SFN increased the phosphorylation of signal transducer and activator of transcription 1 (STAT1), a regulator of macrophage and osteoclast cell fusion. Thus, our data suggested that SFN significantly inhibits the cell-cell fusion molecules DC-STAMP and OC-STAMP by inducing the phosphorylation of STAT1 (Tyr701), which might be regulated by interactions with OSCAR. - Highlights: • Sulforaphane inhibited osteoclast differentiation and osteoclast cell-fusion. • Sulforaphane suppressed not only NFATc1, but also cell-cell fusion molecules, DC-STAMP and OC-STAMP. • Sulforaphane decreased multinucleated osteoclasts, whereas increased mono-nucleated osteoclasts. • Sulforaphane inhibits the cell-cell fusion by inducing the phosphorylation of STAT1 (Tyr701).

  5. Inhibition of nucleotide excision repair by fludarabine in normal lymphocytes in vitro, measured by the alkaline single cell gel electrophoresis (comet) assay

    Energy Technology Data Exchange (ETDEWEB)

    Yamauchi, Takahiro; Kawai, Yasukazu; Ueda, Takanori [Fukui Medical Univ., Matsuoka (Japan)

    2002-05-01

    Alkylating agents or platinum analogues initiate several excision repair mechanisms, which involve incision of the DNA strand, excision of the damaged nucleotide, gap filling by DNA resynthesis, and rejoining by ligation. The previous study described that nucleotide excision repair permitted incorporation of fludarabine nucleoside (F-area-A) into the repair patch, thereby inhibiting the DNA resynthesis. In the present study, to clarify the repair kinetics in view of the inhibition by F-ara-A, normal lymphocytes were stimulated to undergo nucleotide excision repair by ultraviolet C (UV) irradiation in the presence or absence of F-ara-A. The repair kinetics were determined as DNA single strand breaks resulting from the incision and the rejoining using the alkaline single cell gel electrophoresis (comet) assay. DNA resynthesis was evaluated in terms of the uptake of tritiated thymidine into DNA. The lymphocytes initiated the incision step maximally at 1 h, and completed the rejoining process within 4 h after UV exposure. UV also initiated thymidine uptake, which increased time-dependently and reached a plateau at 4 h. A 2-h pre-incubation with F-ara-A inhibited the repair in a concentration-dependent manner, with the maximal inhibition by 5 {mu}M. This inhibitory effect was demonstrated by the reduction of the thymidine uptake and by the inhibition of the rejoining. A DNA polymerase inhibitor, aphidicolin, and a ribonucleotide reductase inhibitor, hydroxyurea, were not so inhibitory to the repair process as F-ara-A at equimolar concentrations. The present findings suggest that inhibition of nucleotide excision repair may represent a novel therapeutic strategy against cancer, especially in the context of resistant cells with an increased repair capacity. (author)

  6. Slow and sustained nitric oxide releasing compounds inhibit multipotent vascular stem cell proliferation and differentiation without causing cell death

    Energy Technology Data Exchange (ETDEWEB)

    Curtis, Brandon M.; Leix, Kyle Alexander [Department of Chemistry, Central Michigan University, Mount Pleasant, MI 48859 (United States); Ji, Yajing [Department of Biomedical Science and Medicine, Michigan State University, East Lansing, MI 48824 (United States); Glaves, Richard Samuel Elliot [Department of Biology, Central Michigan University, Mount Pleasant, MI 48859 (United States); Ash, David E. [Department of Chemistry, Central Michigan University, Mount Pleasant, MI 48859 (United States); Mohanty, Dillip K., E-mail: Mohan1dk@cmich.edu [Department of Chemistry, Central Michigan University, Mount Pleasant, MI 48859 (United States)

    2014-07-18

    Highlights: • Multipotent vascular stem cells (MVSCs) proliferate and differentiate. • Nitric oxide inhibits proliferation of MVSCs. • Nitric oxide inhibits MVSC differentiation to mesenchymal-like stem cells (MSCs). • Smooth muscle cells (SMCs) neither de-differentiate nor proliferate. - Abstract: Atherosclerosis is the leading cause of cerebral and myocardial infarction. It is believed that neointimal growth common in the later stages of atherosclerosis is a result of vascular smooth muscle cell (SMC) de-differentiation in response to endothelial injury. However, the claims of the SMC de-differentiation theory have not been substantiated by monitoring the fate of mature SMCs in response to such injuries. A recent study suggests that atherosclerosis is a consequence of multipotent vascular stem cell (MVSC) differentiation. Nitric oxide (NO) is a well-known mediator against atherosclerosis, in part because of its inhibitory effect on SMC proliferation. Using three different NO-donors, we have investigated the effects of NO on MVSC proliferation. Results indicate that NO inhibits MVSC proliferation in a concentration dependent manner. A slow and sustained delivery of NO proved to inhibit proliferation without causing cell death. On the other hand, larger, single-burst NO concentrations, inhibits proliferation, with concurrent significant cell death. Furthermore, our results indicate that endogenously produced NO inhibits MVSC differentiation to mesenchymal-like stem cells (MSCs) and subsequently to SMC as well.

  7. Automated image-based assay for evaluation of HIV neutralization and cell-to-cell fusion inhibition.

    Science.gov (United States)

    Sheik-Khalil, Enas; Bray, Mark-Anthony; Özkaya Şahin, Gülsen; Scarlatti, Gabriella; Jansson, Marianne; Carpenter, Anne E; Fenyö, Eva Maria

    2014-08-30

    Standardized techniques to detect HIV-neutralizing antibody responses are of great importance in the search for an HIV vaccine. Here, we present a high-throughput, high-content automated plaque reduction (APR) assay based on automated microscopy and image analysis that allows evaluation of neutralization and inhibition of cell-cell fusion within the same assay. Neutralization of virus particles is measured as a reduction in the number of fluorescent plaques, and inhibition of cell-cell fusion as a reduction in plaque area. We found neutralization strength to be a significant factor in the ability of virus to form syncytia. Further, we introduce the inhibitory concentration of plaque area reduction (ICpar) as an additional measure of antiviral activity, i.e. fusion inhibition. We present an automated image based high-throughput, high-content HIV plaque reduction assay. This allows, for the first time, simultaneous evaluation of neutralization and inhibition of cell-cell fusion within the same assay, by quantifying the reduction in number of plaques and mean plaque area, respectively. Inhibition of cell-to-cell fusion requires higher quantities of inhibitory reagent than inhibition of virus neutralization.

  8. Slow and sustained nitric oxide releasing compounds inhibit multipotent vascular stem cell proliferation and differentiation without causing cell death

    International Nuclear Information System (INIS)

    Curtis, Brandon M.; Leix, Kyle Alexander; Ji, Yajing; Glaves, Richard Samuel Elliot; Ash, David E.; Mohanty, Dillip K.

    2014-01-01

    Highlights: • Multipotent vascular stem cells (MVSCs) proliferate and differentiate. • Nitric oxide inhibits proliferation of MVSCs. • Nitric oxide inhibits MVSC differentiation to mesenchymal-like stem cells (MSCs). • Smooth muscle cells (SMCs) neither de-differentiate nor proliferate. - Abstract: Atherosclerosis is the leading cause of cerebral and myocardial infarction. It is believed that neointimal growth common in the later stages of atherosclerosis is a result of vascular smooth muscle cell (SMC) de-differentiation in response to endothelial injury. However, the claims of the SMC de-differentiation theory have not been substantiated by monitoring the fate of mature SMCs in response to such injuries. A recent study suggests that atherosclerosis is a consequence of multipotent vascular stem cell (MVSC) differentiation. Nitric oxide (NO) is a well-known mediator against atherosclerosis, in part because of its inhibitory effect on SMC proliferation. Using three different NO-donors, we have investigated the effects of NO on MVSC proliferation. Results indicate that NO inhibits MVSC proliferation in a concentration dependent manner. A slow and sustained delivery of NO proved to inhibit proliferation without causing cell death. On the other hand, larger, single-burst NO concentrations, inhibits proliferation, with concurrent significant cell death. Furthermore, our results indicate that endogenously produced NO inhibits MVSC differentiation to mesenchymal-like stem cells (MSCs) and subsequently to SMC as well

  9. Susceptibility of human head and neck cancer cells to combined inhibition of glutathione and thioredoxin metabolism.

    Directory of Open Access Journals (Sweden)

    Arya Sobhakumari

    Full Text Available Increased glutathione (GSH and thioredoxin (Trx metabolism are mechanisms that are widely implicated in resistance of cancer cells to chemotherapy. The current study determined if simultaneous inhibition of GSH and Trx metabolism enhanced cell killing of human head and neck squamous cell carcinoma (HNSCC cells by a mechanism involving oxidative stress. Inhibition of GSH and Trx metabolism with buthionine sulfoximine (BSO and auranofin (AUR, respectively, induced significant decreases in clonogenic survival compared to either drug alone in FaDu, Cal-27 and SCC-25 HNSCC cells in vitro and in vivo in Cal-27 xenografts. BSO+AUR significantly increased glutathione and thioredoxin oxidation and suppressed peroxiredoxin activity in vitro. Pre-treatment with N-acetylcysteine completely reversed BSO+AUR-induced cell killing in FaDu and Cal-27 cells, while catalase and selenium supplementation only inhibited BSO+AUR-induced cell killing in FaDu cells. BSO+AUR decreased caspase 3/7 activity in HNSCC cells and significantly reduced the viability of both Bax/Bak double knockout (DKO and DKO-Bax reconstituted hematopoietic cells suggesting that necrosis was involved. BSO+AUR also significantly sensitized FaDu, Cal-27, SCC-25 and SQ20B cells to cell killing induced by the EGFR inhibitor Erlotinib in vitro. These results support the conclusion that simultaneous inhibition of GSH and Trx metabolism pathways induces oxidative stress and clonogenic killing in HNSCCs and this strategy may be useful in sensitizing HNSCCs to EGFR inhibitors.

  10. Aqueous extracts of a Mars analogue regolith that mimics the Phoenix landing site do not inhibit spore germination or growth of model spacecraft contaminants Bacillus subtilis 168 and Bacillus pumilus SAFR-032

    Science.gov (United States)

    Nicholson, Wayne L.; McCoy, Lashelle E.; Kerney, Krystal R.; Ming, Douglas W.; Golden, D. C.; Schuerger, Andrew C.

    2012-08-01

    Because Mars is a primary target for life detection and habitability assessment missions, its exploration is also by necessity a Planetary Protection issue. The recent finding of significant levels of perchlorate (ClO4-) in regolith sampled from the Phoenix landing site raises the question of its potential biotoxicity to putative indigenous martian life, microbial forward contaminants from Earth, or future human visitors. To address this issue, an analogue regolith was constructed based on regolith chemistry data from the Phoenix landing site. A Mars Aqueous Regolith Extract (MARE) was prepared from the Phoenix analogue regolith and analyzed by ion chromatography. The MARE contained (mg/L) the cations Na+ (1411 ± 181), Mg2+ (1051 ± 160), Ca2+ (832 ± 125), and K+ (261 ± 29), and the anions SO42-(5911±993), ClO4-(5316±1767), Cl(171±25) and F- (2.0 ± 0.4). Nitrogen-containing species NO3-(773±113) and NO2-(6.9±2.3) were also present as a result of regolith preparation procedures, but their relevance to Mars is at present unknown. The MARE was tested for potential toxic effects on two model spacecraft contaminants, the spore-forming bacteria Bacillus subtilis strain 168 and Bacillus pumilus strain SAFR-032. In B. subtilis, spore germination and initial vegetative growth (up to ˜5 h) was not inhibited in a rich complex medium prepared with the MARE, but growth after 5 h was significantly suppressed in medium prepared using the MARE. Both B. subtilis and B. pumilus exhibited significantly higher rates of spore germination and growth in the MARE vs. DW with no additions (likely due to endogenous spore nutrients), but germination and growth was further stimulated by addition of glucose and a combination of buffered inorganic salts (K2HPO4, KH2PO4, (NH4)2SO4, and MgSO4). The data indicate that the aqueous environment in the regolith from the Phoenix landing site containing high levels of perchlorate does not pose a significant barrier to growth of putative

  11. Melanogenesis inhibits respiration in B16-F10 melanoma cells whereas enhances mitochondrial cell content

    International Nuclear Information System (INIS)

    Meira, Willian Vanderlei; Heinrich, Tassiele Andréa; Cadena, Silvia Maria Suter Correia; Martinez, Glaucia Regina

    2017-01-01

    Melanoma is a rare and aggressive skin tumor; the survival of patients diagnosed late is fairly low. This high mortality rate is due to the characteristics of the cells that allow them to be resistant to radiotherapy and conventional chemotherapy, besides of being able to evade the immune system. Melanin, the pigment responsible for skin, hair and eye color, seems to be involved in this resistance. The main function of melanin is to protect the cells against ultraviolet (UV) light by absorbing this radiation and reactive oxygen species (ROS) scavenging. But this pigment may have also a role as photosensitizer, because when it is irradiated with UVA light (320-400 nm), the generation of ROS was detected. Besides, the melanogenesis stimulation on B16-F10 cells resulted in cell cycle arrest, induction of a quiescent state, change in the expression of several proteins and alterations on ADP/ATP ratio. The present study aimed to investigate the influence of melanogenesis stimulation in mitochondrial function of B16-F10 melanoma cells. Therefore, we analyzed cells respiration, mitochondrial membrane potential (Δψ_m) and mitochondria mass in B16-F10 melanoma cells stimulated with 0.4 mM L-tyrosine and 10 mM NH_4Cl. Our results showed that the induction of melanin synthesis was able to reduce significantly the oxygen consumption after 48 h of stimulation, without changes of mitochondrial membrane potential when compared to non-stimulated cells. Despite of respiration inhibition, the mitochondria mass was higher in cells with melanogenesis stimulation. We suggest that the stimulation in the melanin synthesis might be promoting the inhibition of electrons transport chain by some intermediate compound from the synthesis of the pigment and this effect could contribute to explain the entry in the quiescent state. - Highlights: • Melanoma pigmentation alters mitochondrial respiration. • Induction of melanin synthesis by 48 h do not change mitochondrial membrane potential

  12. Melanogenesis inhibits respiration in B16-F10 melanoma cells whereas enhances mitochondrial cell content

    Energy Technology Data Exchange (ETDEWEB)

    Meira, Willian Vanderlei; Heinrich, Tassiele Andréa; Cadena, Silvia Maria Suter Correia; Martinez, Glaucia Regina, E-mail: grmartinez@ufpr.br

    2017-01-01

    Melanoma is a rare and aggressive skin tumor; the survival of patients diagnosed late is fairly low. This high mortality rate is due to the characteristics of the cells that allow them to be resistant to radiotherapy and conventional chemotherapy, besides of being able to evade the immune system. Melanin, the pigment responsible for skin, hair and eye color, seems to be involved in this resistance. The main function of melanin is to protect the cells against ultraviolet (UV) light by absorbing this radiation and reactive oxygen species (ROS) scavenging. But this pigment may have also a role as photosensitizer, because when it is irradiated with UVA light (320-400 nm), the generation of ROS was detected. Besides, the melanogenesis stimulation on B16-F10 cells resulted in cell cycle arrest, induction of a quiescent state, change in the expression of several proteins and alterations on ADP/ATP ratio. The present study aimed to investigate the influence of melanogenesis stimulation in mitochondrial function of B16-F10 melanoma cells. Therefore, we analyzed cells respiration, mitochondrial membrane potential (Δψ{sub m}) and mitochondria mass in B16-F10 melanoma cells stimulated with 0.4 mM L-tyrosine and 10 mM NH{sub 4}Cl. Our results showed that the induction of melanin synthesis was able to reduce significantly the oxygen consumption after 48 h of stimulation, without changes of mitochondrial membrane potential when compared to non-stimulated cells. Despite of respiration inhibition, the mitochondria mass was higher in cells with melanogenesis stimulation. We suggest that the stimulation in the melanin synthesis might be promoting the inhibition of electrons transport chain by some intermediate compound from the synthesis of the pigment and this effect could contribute to explain the entry in the quiescent state. - Highlights: • Melanoma pigmentation alters mitochondrial respiration. • Induction of melanin synthesis by 48 h do not change mitochondrial membrane

  13. Norepinephrine inhibition of mesenchymal stem cell and chondrogenic progenitor cell chondrogenesis and acceleration of chondrogenic hypertrophy.

    Science.gov (United States)

    Jenei-Lanzl, Zsuzsa; Grässel, Susanne; Pongratz, Georg; Kees, Frieder; Miosge, Nicolai; Angele, Peter; Straub, Rainer H

    2014-09-01

    Mesenchymal progenitor cell chondrogenesis is the biologic platform for the generation or regeneration of cartilage, but the external influence of the sympathetic nervous system on this process is not yet known. Sympathetic nerve fibers are present in articular tissue, and the sympathetic nervous system influences the musculoskeletal system by, for example, increasing osteoclastogenesis. This study was initiated to explore the role of the sympathetic neurotransmitter norepinephrine (NE) in mesenchymal stem cell (MSC)-dependent and cartilage progenitor cell (CPC)-dependent chondrogenesis. Using human MSCs or CPCs, chondrogenic differentiation was induced in the presence of NE, the specific β-adrenergic receptor (β-AR) agonist isoproterenol, and the specific β-AR antagonist nadolol. We studied sympathetic nerve fibers, tyrosine hydroxylase (TH) expression, catecholamine biosynthesis, and synovial fluid levels in human joints, as well as cartilage-specific matrix deposition during differentiation. TH+ sympathetic nerve fibers were present in the synovial tissue, meniscus, and subchondral bone marrow. In addition, synovial fluid from patients with knee trauma demonstrated high concentrations of NE. During MSC or CPC chondrogenesis, β-AR were expressed. Chondrogenic aggregates treated with NE or isoproterenol synthesized lower amounts of type II collagen and glycosaminoglycans. NE and isoproterenol treatment dose-dependently increased the levels of cartilage hypertrophy markers (type X collagen and matrix metalloproteinase 13). Nadolol reversed the inhibition of chondrogenesis and the up-regulation of cartilage hypertrophy. Our findings demonstrate NE-dependent inhibition of chondrogenesis and acceleration of hypertrophic differentiation. By inhibiting cartilage repair, these sympathetic influences can be important after joint trauma. These findings may be a basis for novel neurochondrogenic therapeutic options. Copyright © 2014 by the American College of

  14. Midkine inhibits inducible regulatory T cell differentiation by suppressing the development of tolerogenic dendritic cells.

    Science.gov (United States)

    Sonobe, Yoshifumi; Li, Hua; Jin, Shijie; Kishida, Satoshi; Kadomatsu, Kenji; Takeuchi, Hideyuki; Mizuno, Tetsuya; Suzumura, Akio

    2012-03-15

    Midkine (MK), a heparin-binding growth factor, reportedly contributes to inflammatory diseases, including Crohn's disease and rheumatoid arthritis. We previously showed that MK aggravates experimental autoimmune encephalomyelitis (EAE) by decreasing regulatory CD4(+)CD25(+)Foxp3(+) T cells (Tregs), a population that regulates the development of autoimmune responses, although the precise mechanism remains uncertain. In this article, we show that MK produced in inflammatory conditions suppresses the development of tolerogenic dendritic cells (DCregs), which drive the development of inducible Treg. MK suppressed DCreg-mediated expansion of the CD4(+)CD25(+)Foxp3(+) Treg population. DCregs expressed significantly higher levels of CD45RB and produced significantly less IL-12 compared with conventional dendritic cells. However, MK downregulated CD45RB expression and induced IL-12 production by reducing phosphorylated STAT3 levels via src homology region 2 domain-containing phosphatase-2 in DCreg. Inhibiting MK activity with anti-MK RNA aptamers, which bind to the targeted protein to suppress the function of the protein, increased the numbers of CD11c(low)CD45RB(+) dendritic cells and Tregs in the draining lymph nodes and suppressed the severity of EAE, an animal model of multiple sclerosis. Our results also demonstrated that MK was produced by inflammatory cells, in particular, CD4(+) T cells under inflammatory conditions. Taken together, these results suggest that MK aggravates EAE by suppressing DCreg development, thereby impairing the Treg population. Thus, MK is a promising therapeutic target for various autoimmune diseases.

  15. Melatonin Cytotoxicity Is Associated to Warburg Effect Inhibition in Ewing Sarcoma Cells.

    Directory of Open Access Journals (Sweden)

    Ana M Sanchez-Sanchez

    Full Text Available Melatonin kills or inhibits the proliferation of different cancer cell types, and this is associated with an increase or a decrease in reactive oxygen species, respectively. Intracellular oxidants originate mainly from oxidative metabolism, and cancer cells frequently show alterations in this metabolic pathway, such as the Warburg effect (aerobic glycolysis. Thus, we hypothesized that melatonin could also regulate differentially oxidative metabolism in cells where it is cytotoxic (Ewing sarcoma cells and in cells where it inhibits proliferation (chondrosarcoma cells. Ewing sarcoma cells but not chondrosarcoma cells showed a metabolic profile consistent with aerobic glycolysis, i.e. increased glucose uptake, LDH activity, lactate production and HIF-1α activation. Melatonin reversed Ewing sarcoma metabolic profile and this effect was associated with its cytotoxicity. The differential regulation of metabolism by melatonin could explain why the hormone is harmless for a wide spectrum of normal and only a few tumoral cells, while it kills specific tumor cell types.

  16. Inhibition of microparticle release triggers endothelial cell apoptosis and detachment

    NARCIS (Netherlands)

    Abid Hussein, Mohammed N.; Böing, Anita N.; Sturk, Augueste; Hau, Chi M.; Nieuwland, Rienk

    2007-01-01

    Endothelial cell cultures contain caspase 3-containing microparticles (EMP), which are reported to form during or after cell detachment. We hypothesize that also adherent endothelial cells release EMP, thus protecting these cells from caspase 3 accumulation, detachment and apoptosis. Human umbilical

  17. Benzylidene derivatives of andrographolide inhibit growth of breast and colon cancer cells in vitro by inducing G1 arrest and apoptosis

    Science.gov (United States)

    Jada, S R; Matthews, C; Saad, M S; Hamzah, A S; Lajis, N H; Stevens, M F G; Stanslas, J

    2008-01-01

    Background and purpose: Andrographolide, the major phytoconstituent of Andrographis paniculata, was previously shown by us to have activity against breast cancer. This led to synthesis of new andrographolide analogues to find compounds with better activity than the parent compound. Selected benzylidene derivatives were investigated for their mechanisms of action by studying their effects on the cell cycle progression and cell death. Experimental approach: Microculture tetrazolium, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) and sulphorhodamine B (SRB) assays were utilized in assessing the in vitro growth inhibition and cytotoxicity of compounds. Flow cytometry was used to analyse the cell cycle distribution of control and treated cells. CDK1 and CDK4 levels were determined by western blotting. Apoptotic cell death was assessed by fluorescence microscopy and flow cytometry. Key results: Compounds, in nanomolar to micromolar concentrations, exhibited growth inhibition and cytotoxicity in MCF-7 (breast) and HCT-116 (colon) cancer cells. In the NCI screen, 3,19-(2-bromobenzylidene) andrographolide (SRJ09) and 3,19-(3-chloro-4-fluorobenzylidene) andrographolide (SRJ23) showed greater cytotoxic potency and selectivity than andrographolide. SRJ09 and SRJ23 induced G1 arrest and apoptosis in MCF-7 and HCT-116 cells, respectively. SRJ09 downregulated CDK4 but not CDK1 level in MCF-7 cells. Apoptosis induced by SRJ09 and SRJ23 in HCT-116 cells was confirmed by annexin V-FITC/PI flow cytometry analysis. Conclusion and implications: The new benzylidene derivatives of andrographolide are potential anticancer agents. SRJ09 emerged as the lead compound in this study, exhibiting anticancer activity by downregulating CDK4 to promote a G1 phase cell cycle arrest, coupled with induction of apoptosis. PMID:18806812

  18. Inhibition of para-Hydroxyphenylpyruvate Dioxygenase by Analogues of the Herbicide Nitisinone As a Strategy to Decrease Homogentisic Acid Levels, the Causative Agent of Alkaptonuria.

    Science.gov (United States)

    Laschi, Marcella; Bernardini, Giulia; Dreassi, Elena; Millucci, Lia; Geminiani, Michela; Braconi, Daniela; Marzocchi, Barbara; Botta, Maurizio; Manetti, Fabrizio; Santucci, Annalisa

    2016-04-05

    Alkaptonuria (AKU) is a rare multisystem metabolic disease caused by deficient activity of homogentisate 1,2-dioxygenase (HGD), which leads to the accumulation of homogentisic acid (HGA). Currently, there is no treatment for AKU. The sole drug with some beneficial effects is the herbicide nitisinone (1), an inhibitor of p-hydroxyphenylpyruvate dioxygenase (4-HPPD). 1 has been used as a life-saving drug in infants with type I tyrosinemia despite severe side effects due to the buildup of tyrosine. Four clinical trials of nitisinone to treat AKU have shown that 1 consistently decreases HGA levels, but also caused the accumulation of tyrosine in blood serum. Moreover, the human preclinical toxicological data for 1 are incomplete. In this work, we performed pharmacodynamics and toxicological evaluations of 1, providing the first report of LD50 values in human cells. Intracellular tyrosinemia was also evaluated. Three additional 4-HPPD inhibitors with a more favorable profile than that of 1 in terms of IC50, LD50, and tyrosine accumulation were also identified among commercially available compounds. These may be promising starting points for the development of new therapeutic strategies for the treatment of AKU. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. SAMHD1 is down regulated in lung cancer by methylation and inhibits tumor cell proliferation

    International Nuclear Information System (INIS)

    Wang, Jia-lei; Lu, Fan-zhen; Shen, Xiao-Yong; Wu, Yun; Zhao, Li-ting

    2014-01-01

    Highlights: • SAMHD1 expression level is down regulated in lung adenocarcinoma. • The promoter of SAMHD1 is methylated in lung adenocarcinoma. • Over expression of SAMHD1 inhibits the proliferation of lung cancer cells. - Abstract: The function of dNTP hydrolase SAMHD1 as a viral restriction factor to inhibit the replication of several viruses in human immune cells was well established. However, its regulation and function in lung cancer have been elusive. Here, we report that SAMHD1 is down regulated both on protein and mRNA levels in lung adenocarcinoma compared to adjacent normal tissue. We also found that SAMHD1 promoter is highly methylated in lung adenocarcinoma, which may inhibit its gene expression. Furthermore, over expression of the SAMHD1 reduces dNTP level and inhibits the proliferation of lung tumor cells. These results reveal the regulation and function of SAMHD1 in lung cancer, which is important for the proliferation of lung tumor cells

  20. Function-oriented synthesis: biological evaluation of laulimalide analogues derived from a last step cross metathesis diversification strategy.

    Science.gov (United States)

    Mooberry, Susan L; Hilinski, Michael K; Clark, Erin A; Wender, Paul A

    2008-01-01

    Laulimalide is a potent microtubule stabilizing agent and a promising anticancer therapeutic lead. The identification of stable, efficacious and accessible analogues is critical to clinically exploiting this novel lead. To determine which structural features of laulimalide are required for beneficial function and thus for accessing superior clinical candidates, a series of side chain analogues were prepared through a last step cross metathesis diversification strategy and their biological activities were evaluated. Five analogues, differing in potency from 233 nM to 7.9 muM, effectively inhibit cancer cell proliferation. Like laulimalide, they retain activity against multidrug resistant cells, stabilize microtubules and cause the formation of aberrant mitotic spindles, mitotic accumulation, Bcl-2 phosphorylation and initiation of apoptosis. Structural modifications in the C 23-C 27 dihydropyran side chain can be made without changing the overall mechanism of action, but it is clear that this subunit has more than a bystander role.

  1. Inhibition of autophagy induced by TSA sensitizes colon cancer cell to radiation.

    Science.gov (United States)

    He, Gang; Wang, Yan; Pang, Xueli; Zhang, Bo

    2014-02-01

    Radiotherapy is one of the main treatments for clinical cancer therapy. However, its application was limited due to lack of radiosensitivity in some cancers. Trichostatin A (TSA) is a classic histone deacetylases inhibitor (HDACi) that specifically inhibits the biochemical functions of HDAC and is demonstrated to be an active anticancer drug. However, whether it could sensitize colon cancer to radiation is not clear. Our results showed that TSA enhanced the radiosensitivity of colon cancer cells as determined by CCK-8 and clonogenic survival assay. Moreover, apoptotic cell death induced by radiation was enhanced by TSA treatment. Additionally, TSA also induced autophagic response in colon cancer cells, while autophagy inhibition led to cell apoptosis and enhanced the radiosensitivity of colon cancer cells. Our data suggested that inhibition of cytoprotective autophagy sensitizes cancer cell to radiation, which might be further investigated for clinical cancer radiotherapy.

  2. Time-lapse cinematography of the capillary tube cell migration inhibition test.

    Science.gov (United States)

    Bray, M A

    1980-01-01

    The kinetics of human and guinea pig cell migration inhibition have been studied using time-lapse cinematography of cells migrating from capillary tubes. Guinea pig and human cells exhibit markedly different kinetics in the absence of inhibitors. Specific antigen causes a dose-related inhibition of migration for up to 60 h using guinea pig cells and a peak of inhibition after 18 h using the human leucocyte system. The timing of measurement of maximum activity more critical for the latter test. The kinetics of lymphokine generation have been examined and the migration inhibitory activity of the plant mitogen (PHA), a Kurloff cell product and a continuous cell line supernatant have been compared with the inhibitory profiles of lymphokine preparations and specific antigen.

  3. Induction of cell-cell fusion by ectromelia virus is not inhibited by its fusion inhibitory complex

    Directory of Open Access Journals (Sweden)

    Fuchs Pinhas

    2009-09-01

    Full Text Available Abstract Background Ectromelia virus, a member of the Orthopox genus, is the causative agent of the highly infectious mousepox disease. Previous studies have shown that different poxviruses induce cell-cell fusion which is manifested by the formation of multinucleated-giant cells (polykaryocytes. This phenomenon has been widely studied with vaccinia virus in conditions which require artificial acidification of the medium. Results We show that Ectromelia virus induces cell-cell fusion under neutral pH conditions and requires the presence of a sufficient amount of viral particles on the plasma membrane of infected cells. This could be achieved by infection with a replicating virus and its propagation in infected cells (fusion "from within" or by infection with a high amount of virus particles per cell (fusion "from without". Inhibition of virus maturation or inhibition of virus transport on microtubules towards the plasma membrane resulted in a complete inhibition of syncytia formation. We show that in contrast to vaccinia virus, Ectromelia virus induces cell-cell fusion irrespectively of its hemagglutination properties and cell-surface expression of the orthologs of the fusion inhibitory complex, A56 and K2. Additionally, cell-cell fusion was also detected in mice lungs following lethal respiratory infection. Conclusion Ectromelia virus induces spontaneous cell-cell fusion in-vitro and in-vivo although expressing an A56/K2 fusion inhibitory complex. This syncytia formation property cannot be attributed to the 37 amino acid deletion in ECTV A56.

  4. Extracellular ATP inhibits Schwann cell dedifferentiation and proliferation in an ex vivo model of Wallerian degeneration

    International Nuclear Information System (INIS)

    Shin, Youn Ho; Lee, Seo Jin; Jung, Junyang

    2013-01-01

    Highlights: ► ATP-treated sciatic explants shows the decreased expression of p75NGFR. ► Extracellular ATP inhibits the expression of phospho-ERK1/2. ► Lysosomal exocytosis is involved in Schwann cell dedifferentiation. ► Extracellular ATP blocks Schwann cell proliferation in sciatic explants. -- Abstract: After nerve injury, Schwann cells proliferate and revert to a phenotype that supports nerve regeneration. This phenotype-changing process can be viewed as Schwann cell dedifferentiation. Here, we investigated the role of extracellular ATP in Schwann cell dedifferentiation and proliferation during Wallerian degeneration. Using several markers of Schwann cell dedifferentiation and proliferation in sciatic explants, we found that extracellular ATP inhibits Schwann cell dedifferentiation and proliferation during Wallerian degeneration. Furthermore, the blockage of lysosomal exocytosis in ATP-treated sciatic explants is sufficient to induce Schwann cell dedifferentiation. Together, these findings suggest that ATP-induced lysosomal exocytosis may be involved in Schwann cell dedifferentiation.

  5. Pectin methyl esterase inhibits intrusive and symplastic cell growth in developing wood cells of Populus.

    Science.gov (United States)

    Siedlecka, Anna; Wiklund, Susanne; Péronne, Marie-Amélie; Micheli, Fabienne; Lesniewska, Joanna; Sethson, Ingmar; Edlund, Ulf; Richard, Luc; Sundberg, Björn; Mellerowicz, Ewa J

    2008-02-01

    Wood cells, unlike most other cells in plants, grow by a unique combination of intrusive and symplastic growth. Fibers grow in diameter by diffuse symplastic growth, but they elongate solely by intrusive apical growth penetrating the pectin-rich middle lamella that cements neighboring cells together. In contrast, vessel elements grow in diameter by a combination of intrusive and symplastic growth. We demonstrate that an abundant pectin methyl esterase (PME; EC 3.1.1.11) from wood-forming tissues of hybrid aspen (Populus tremula x tremuloides) acts as a negative regulator of both symplastic and intrusive growth of developing wood cells. When PttPME1 expression was up- and down-regulated in transgenic aspen trees, the PME activity in wood-forming tissues was correspondingly altered. PME removes methyl ester groups from homogalacturonan (HG) and transgenic trees had modified HG methylesterification patterns, as demonstrated by two-dimensional nuclear magnetic resonance and immunostaining using PAM1 and LM7 antibodies. In situ distributions of PAM1 and LM7 epitopes revealed changes in pectin methylesterification in transgenic trees that were specifically localized in expanding wood cells. The results show that en block deesterification of HG by PttPME1 inhibits both symplastic growth and intrusive growth. PttPME1 is therefore involved in mechanisms determining fiber width and length in the wood of aspen trees.

  6. MTSS1 is epigenetically regulated in glioma cells and inhibits glioma cell motility

    Directory of Open Access Journals (Sweden)

    Daniel Luxen

    2017-02-01

    Full Text Available Epigenetic silencing by DNA methylation in brain tumors has been reported for many genes, however, their function on pathogenesis needs to be evaluated. We investigated the MTSS1 gene, identified as hypermethylated by differential methylation hybridization (DMH. Fifty-nine glioma tissue samples and seven glioma cell lines were examined for hypermethylation of the MTSS1 promotor, MTSS1 expression levels and gene dosage. GBM cell lines were treated with demethylating agents and interrogated for functional consequences of MTSS1 expression after transient transfection. Hypermethylation was significantly associated with IDH1/2 mutation. Comparative SNP analysis indicates higher incidence of loss of heterozygosity of MTSS1 in anaplastic astrocytomas and secondary glioblastomas as well as hypermethylation of the remaining allele. Reversal of promoter hypermethylation results in an increased MTSS1 expression. Cell motility was significantly inhibited by MTSS1 overexpression without influencing cell growth or apoptosis. Immunofluorescence analysis of MTSS1 in human astrocytes indicates co-localization with actin filaments. MTSS1 is down-regulated by DNA methylation in glioblastoma cell lines and is part of the G-CIMP phenotype in primary glioma tissues. Our data on normal astrocytes suggest a function of MTSS1 at focal contact structures with an impact on migratory capacity but no influence on apoptosis or cellular proliferation.

  7. TLR4 plays a crucial role in MSC-induced inhibition of NK cell function

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Ying [No. 307 Hospital of the Chinese People' s Liberation Army, Beijing (China); Liu, Jin; Liu, Yang; Qin, Yaru [Beijing Institute of Radiation Medicine, Beijing (China); Luo, Qun [No. 307 Hospital of the Chinese People' s Liberation Army, Beijing (China); Wang, Quanli, E-mail: 13691110351@163.com [No. 307 Hospital of the Chinese People' s Liberation Army, Beijing (China); Duan, Haifeng, E-mail: duanhf0720@163.com [Beijing Institute of Radiation Medicine, Beijing (China)

    2015-08-21

    Mesenchymal stem cells (MSC) are a kind of stromal cell within the tumor microenvironment. In our research, MSC derived from acute myeloid leukemia patients' bone marrow (AML-MSC) and lung cancer tissues (LC-MSC) as well as normal bone marrow-derived MSC (BM-MSC) cultured in conditioned medium of HeLa cells were found to have higher expressions of Toll-like receptor (TLR4) mRNA compared with BM-MSC. The sorted TLR4-positive MSC (TLR4+ MSC) differed in cytokine (interleukin-6, interleukin-8, and monocyte chemoattractant protein-1) secretion from those of unsorted MSC. MSC was reported to inhibit natural killer (NK) cell proliferation and function. In this research, we confirmed that TLR4+ MSC aggravate this suppression. Furthermore, when TLR4 in the sorted cells were stimulated by LPS or following blocked by antibody, the suppression on NK cell proliferation and cytotoxicity were more intensive or recovered respectively. Compared to unsorted MSC, NKG2D receptor expression on NK cells were also inhibited by TLR4+ MSC. These findings suggest that activation of TLR4 pathway is important for TLR4+ MSC and MSC to obstruct anti-tumor immunity by inhibiting NK cell function, which may provide a potential stroma-targeted tumor therapy. - Highlights: • TLR4+ MSC inhibit NK cell proliferation in vivo and in vitro. • TLR4+ MSC inhibit NKG2D expression on NK cells and NK cell cytotoxicity. • The distinguished cytokine expression of TLR4+ MSC may contribute to the inhibition on NK cell function.

  8. Naturally Inspired Peptide Leads: Alanine Scanning Reveals an Actin-Targeting Thiazole Analogue of Bisebromoamide.

    Science.gov (United States)

    Johnston, Heather J; Boys, Sarah K; Makda, Ashraff; Carragher, Neil O; Hulme, Alison N

    2016-09-02

    Systematic alanine scanning of the linear peptide bisebromoamide (BBA), isolated from a marine cyanobacterium, was enabled by solid-phase peptide synthesis of thiazole analogues. The analogues have comparable cytotoxicity (nanomolar) to that of BBA, and cellular morphology assays indicated that they target the actin cytoskeleton. Pathway inhibition in human colon tumour (HCT116) cells was explored by reverse phase protein array (RPPA) analysis, which showed a dose-dependent response in IRS-1 expression. Alanine scanning reveals a structural dependence to the cytotoxicity, actin targeting and pathway inhibition, and allows a new readily synthesised lead to be proposed. © 2016 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.

  9. IL-15 inhibits pre-B cell proliferation by selectively expanding Mac-1+B220+ NK cells

    International Nuclear Information System (INIS)

    Nakajima, Shinsuke; Hida, Shigeaki; Taki, Shinsuke

    2008-01-01

    Natural killer (NK) cells are the cells critical for inhibition of repopulation of allogenic bone marrow cells. However, it is not well known if NK cells affect autologous lymphopoiesis. Here, we observed that NK cells could inhibit pre-B cell proliferation in vitro driven by interleukin (IL)-7 in a manner dependent on IL-15. Interestingly, the great majority of expanding NK cells were Mac-1 + B220 + , a recently identified potent interferon (IFN)-γ producer. Indeed, IFN-γ was produced in those cultures, and pre-B cells lacking IFN-γ receptors, but not those lacking type I IFN receptors, were resistant to such an inhibition. Furthermore, even NK cells from mice lacking β2-microglobulin, which were known to be functionally dampened, inhibited pre-B cell proliferation as well. Thus, activated NK cells, which were expanded selectively by IL-15, could potentially regulate B lymphopoiesis through IFN-γ beyond the selection imposed upon self-recognition

  10. Inhibition of platelet-tumour cell interaction with ibrutinib reduces ...

    African Journals Online (AJOL)

    BTK) inhibitor, ibrutinib, in tumour cell-platelet crosstalk in lung cancer. Methods: Human lung cancer cells A549 were treated with ibrutinib or DMSO. mRNA expression was assessed using reverse transcription-quantitative polymerase chain ...

  11. MicroRNA-144 inhibits hepatocellular carcinoma cell proliferation ...

    Indian Academy of Sciences (India)

    2017-01-20

    Jan 20, 2017 ... suppressor in HCC cell growth and motility by directly targeting ZFX, which implicates its potential ... play important regulatory roles in the post-transcriptional .... luciferase reporter assay, HCC cells were seeded into 24-.

  12. Sprouty regulates cell migration by inhibiting the activation of Rac1 GTPase

    International Nuclear Information System (INIS)

    Poppleton, Helen M.; Edwin, Francis; Jaggar, Laura; Ray, Ramesh; Johnson, Leonard R.; Patel, Tarun B.

    2004-01-01

    Sprouty (SPRY) protein negatively modulates fibroblast growth factor and epidermal growth factor actions. We showed that human SPRY2 inhibits cell growth and migration in response to serum and several growth factors. Using rat intestinal epithelial (IEC-6) cells, we investigated the involvement of the Rho family of GTPases, RhoA, Rac1, and cdc42 in SPRY2-mediated inhibition of cell migration and proliferation. The ability of TAT-tagged SPRY2 to inhibit proliferation and migration of IEC-6 cells transfected with constitutively active mutants of RhoA(G14V), Rac1(G12V), and cdc42 (F28L) was determined. Constitutively active RhoA(G14V), Rac1(G12V), or cdc42(F28L) did not protect cells from the anti-proliferative actions of TAT-SPRY2. The ability of TAT-hSPRY2 to inhibit migration was not altered by of RhoA(G14V) and cdc42(F28L). However, Rac1(G12V) obliterated the ability of SPRY2 to inhibit cell autonomous or serum-induced migration. Also, the activation of endogenous Rac1 was attenuated by TAT-SPRY2. Thus, SPRY2 mediates its anti-migratory actions by inhibiting Rac1 activation

  13. BMPR2 inhibition induced apoptosis and autophagy via destabilization of XIAP in human chondrosarcoma cells

    Science.gov (United States)

    Jiao, G; Guo, W; Ren, T; Lu, Q; Sun, Y; Liang, W; Ren, C; Yang, K; Sun, K

    2014-01-01

    Bone morphogenetic proteins (BMPs) are multifunctional proteins, and their receptors (BMPRs) have crucial roles in the process of signaling. However, their function in cancer is somewhat inconsistent. It has been demonstrated that more prevalent expression of bone morphogenetic protein receptor 2 (BMPR2) has been detected in dedifferentiated chondrosarcomas than conventional chondrosarcomas. Here, we find that BMPR2 inhibition induces apoptosis and autophagy of chondrosarcoma. We found that BMPR2 expression was correlated with the clinicopathological features of chondrosarcomas, and could predict the treatment outcome. Knockdown of BMPR2 by small interfering RNA results in growth inhibition in chondrosarcoma cells. Silencing BMPR2 promoted G2/M cell cycle arrest, induced chondrosarcoma cell apoptosis through caspase-3-dependent pathway via repression of X-linked inhibitor of apoptosis protein (XIAP) and induced autophagy of chondrosarcoma cells via XIAP-Mdm2-p53 pathway. Inhibition of autophagy induced by BMPR2 small interfering RNA (siBMPR2) sensitized chondrosarcoma cells to siBMPR2-induced apoptotic cell death, suggesting that autophagy has a protective role for chondrosarcoma cells in context of siBMPR2-induced apoptotic cell death. In vivo tumorigenicity assay in mice indicated that inhibition of BMPR2 reduced tumor growth. Taken together, our results suggest that BMPR2 has a significant role in the tumorigenesis of chondrosarcoma, and could be an important prognostic marker for chondrosarcoma. BMPR2 inhibition could eventually provide a promising therapy for chondrosarcoma treatment. PMID:25501832

  14. NAC selectively inhibit cancer telomerase activity: A higher redox homeostasis threshold exists in cancer cells

    Directory of Open Access Journals (Sweden)

    Pengying Li

    2016-08-01

    Full Text Available Telomerase activity controls telomere length, and this plays an important role in stem cells, aging and tumors. Antioxidant was shown to protect telomerase activity in normal cells but inhibit that in cancer cells, but the underlying mechanism is elusive. Here we found that 7721 hepatoma cells held a higher redox homeostasis threshold than L02 normal liver cells which caused 7721 cells to have a higher demand for ROS; MnSOD over-expression in 7721 decreased endogenous reactive oxygen species (ROS and inhibited telomerase activity; Akt phosphorylation inhibitor and NAC both inhibited 7721 telomerase activity. The over-elimination of ROS by NAC resulted in the inhibition of Akt pathway. Our results suggest that ROS is involved in the regulation of cancer telomerase activity through Akt pathway. The different intracellular redox homeostasis and antioxidant system in normal cells and tumor cells may be the cause of the opposite effect on telomerase activity in response to NAC treatment. Our results provide a theoretical base of using antioxidants selectively inhibit cancer telomerase activity. Findings of the present study may provide insights into novel approaches for cancer treatment.

  15. Inhibition of Pancreatic Cancer Cell Proliferation by LRH-1 Inhibitors

    Science.gov (United States)

    2014-12-01

    Synthesis of polyphosphoinositides in nuclei of Friend cells. Evidence for polyphosphoinositide metabolism inside the nucleus which changes with cell...537, S531-532. 23. de Saint-Jean M, et al. (2011) Osh4p exchanges sterols for phosphatidylinositol 4-phosphate between lipid bilayers. J Cell Biol 195(6

  16. Curcumin Inhibits Growth of Human NCI-H292 Lung Squamous Cell Carcinoma Cells by Increasing FOXA2 Expression

    Directory of Open Access Journals (Sweden)

    Lingling Tang

    2018-02-01

    Full Text Available Lung squamous cell carcinoma (LSCC is a common histological lung cancer subtype, but unlike lung adenocarcinoma, limited therapeutic options are available for treatment. Curcumin, a natural compound, may have anticancer effects in various cancer cells, but how it may be used to treat LSCC has not been well studied. Here, we applied curcumin to a human NCI-H292 LSCC cell line to test anticancer effects and explored underlying potential mechanisms of action. Curcumin treatment inhibited NCI-H292 cell growth and increased FOXA2 expression in a time-dependent manner. FOXA2 expression was decreased in LSCC tissues compared with adjacent normal tissues and knockdown of FOXA2 increased NCI-H292 cells proliferation. Inhibition of cell proliferation by curcumin was attenuated by FOXA2 knockdown. Moreover inhibition of STAT3 pathways by curcumin increased FOXA2 expression in NCI-H292 cells whereas a STAT3 activator (IL-6 significantly inhibited curcumin-induced FOXA2 expression. Also, SOCS1 and SOCS3, negative regulators of STAT3 activity, were upregulated by curcumin treatment. Thus, curcumin inhibited human NCI-H292 cells growth by increasing FOXA2 expression via regulation of STAT3 signaling pathways.

  17. In Silico Screening and In Vitro Activity Measurement of Javamide Analogues as Potential p38 MAPK Inhibitors

    Directory of Open Access Journals (Sweden)

    Jae B. Park

    2017-12-01

    Full Text Available p38 Mitogen-activated protein kinase (p38 MAPK is a protein kinase critically involved in the progress of inflammation/stress-associated diseases. Our data suggested that javamide analogues may contain strong anti-inflammation activities, but there is little information about their effects on p38 MAPK. Therefore, in this paper, the effects of thirty javamide analogues on p38 MAPK were investigated using in silico screening and in vitro p38 MAPK assay methods. The javamide analogues were synthesized and their chemical structures were confirmed using nuclear magnetic resonance (NMR spectroscopic methods. Then, the javamide analogues were screened using an in silico modeling program. The screened analogues demonstrated a wide range of binding energy (ΔE; −20 to −39 and several analogues with ΔE; −34 to −39 showed strong binding affinity to p38 MAPK. In vitro p38 MAPK assay, the kinase was significantly inhibited by the analogues with great binding energy (ΔE; −34 to −39 and in silico scores (Avg. score; −27.5 to −29.3. Furthermore, the comparative analysis of both assays showed a positive correlation between the in silico scores and p38 MAPK inhibition. In fact, the javamide analogues with top five in silico scores (Avg. score; −27.5 to −29.3 were found to inhibit p38 MAPK by 27–31% (p < 0.05 better than those with less scores (ΔE < −27.0. Especially, javamide-II-O-ethyl ester with relatively high in silico score (Avg. score; −29.2 inhibited p38 MAPK (IC50 = 9.9 μM a little better than its methyl ester with best in silico score (Avg. score; −29.3. To support the ability to inhibit p38 MAPK, the treatment of javamide-II-ethyl and -methyl esters could suppress the production of IL-8 and MCP-1 protein significantly by 22–73% (p < 0.05 in the differentiated THP-1 cells, and the inhibition was slightly stronger by the ethyl ester than the methyl ester. Altogether, this study suggests that javamide-II-O-ethyl ester may

  18. Mixed metal oxide nanoparticles inhibit growth of Mycobacterium tuberculosis into THP-1 cells

    Directory of Open Access Journals (Sweden)

    A R Jafari

    2016-01-01

    Conclusion: Although Ag NPs exhibited low cytotoxicity, they were unable to inhibit Mtb growth in vitro. ZnO NPs exhibited strong anti-Mtb activity and inhibited bacterial growth, but exhibited high cytotoxicity to human macrophage cells. By mixing Ag and ZnO NPs at a ratio of 8ZnO/2Ag, we acquired a mixture that exhibited potent antibacterial activity against Mtb and no cytotoxic effects on THP-1 cells, resulting in inhibition of both in vitro and ex vivo Mtb growth [Figure 1],[Figure 2],[Figure 3], [Table 1],[Table 2],[Table 3].{Figure 1}{Figure 2}{Figure 3} {Table 1}{Table 2}{Table 3}

  19. p8 inhibits the growth of human pancreatic cancer cells and its expression is induced through pathways involved in growth inhibition and repressed by factors promoting cell growth

    Directory of Open Access Journals (Sweden)

    Vasseur Sophie

    2003-11-01

    Full Text Available Abstract Background p8 is a stress-induced protein with multiple functions and biochemically related to the architectural factor HMG-I/Y. We analyzed the expression and function of p8 in pancreatic cancer-derived cells. Methods Expression of p8 was silenced in the human pancreatic cancer cell lines Panc-1 and BxPc-3 by infection with a retrovirus expressing p8 RNA in the antisense orientation. Cell growth was measured in control and p8-silenced cells. Influence on p8 expression of the induction of intracellular pathways promoting cellular growth or growth arrest was monitored. Results p8-silenced cells grew more rapidly than control cells transfected with the empty retrovirus. Activation of the Ras→Raf→MEK→ERK and JNK intracellular pathways down-regulated p8 expression. In addition, the MEK1/2 inhibitor U0126 and the JNK inhibitor SP600125 up-regulates expression of p8. Conversely, p38 or TGFβ-1 induced p8 expression whereas the specific p38 inhibitor SB203580 down-regulated p8 expression. Finally, TGFβ-1 induction was in part mediated through p38. Conclusions p8 inhibits the growth of human pancreatic cancer cells. p8 expression is induced through pathways involved in growth inhibition and repressed by factors that promote cell growth. These results suggest that p8 belongs to a pathway regulating the growth of pancreatic cancer cells.

  20. Inhibition of Cell Differentiation in Bacillus subtilis by Pseudomonas protegens

    Science.gov (United States)

    Powers, Matthew J.; Sanabria-Valentín, Edgardo; Bowers, Albert A.

    2015-01-01

    ABSTRACT Interspecies interactions have been described for numerous bacterial systems, leading to the identification of chemical compounds that impact bacterial physiology and differentiation for processes such as biofilm formation. Here, we identified soil microbes that inhibit biofilm formation and sporulation in the common soil bacterium Bacillus subtilis. We did so by creating a reporter strain that fluoresces when the transcription of a biofilm-specific gene is repressed. Using this reporter in a coculture screen, we identified Pseudomonas putida and Pseudomonas protegens as bacteria that secrete compounds that inhibit biofilm gene expression in B. subtilis. The active compound produced by P. protegens was identified as the antibiotic and antifungal molecule 2,4-diacetylphloroglucinol (DAPG). Colonies of B. subtilis grown adjacent to a DAPG-producing P. protegens strain had altered colony morphologies relative to B. subtilis colonies grown next to a DAPG-null P. protegens strain (phlD strain). Using a subinhibitory concentration of purified DAPG in a pellicle assay, we saw that biofilm-specific gene transcription was delayed relative to transcription in untreated samples. These transcriptional changes also corresponded to phenotypic alterations: both biofilm biomass and spore formation were reduced in B. subtilis liquid cultures treated with subinhibitory concentrations of DAPG. Our results add DAPG to the growing list of antibiotics that impact bacterial development and physiology at subinhibitory concentrations. These findings also demonstrate the utility of using coculture as a means to uncover chemically mediated interspecies interactions between bacteria. IMPORTANCE Biofilms are communities of bacteria adhered to surfaces by an extracellular matrix; such biofilms can have important effects in both clinical and agricultural settings. To identify chemical compounds that inhibited biofilm formation, we used a fluorescent reporter to screen for bacteria that

  1. Mesenchymal stem cells inhibit lymphocyte proliferation by mitogens and alloantigens by different mechanisms

    International Nuclear Information System (INIS)

    Rasmusson, Ida; Ringden, Olle; Sundberg, Berit; Le Blanc, Katarina

    2005-01-01

    Human mesenchymal stem cells (MSCs) have immuno-modulatory properties. They inhibit T-cell proliferation to mitogens and alloantigens in vitro and prolong skin graft survival in vivo. We found that MSCs inhibited the proliferation of peripheral blood lymphocytes (PBLs) to phorbol myristate acetate (PMA), suggesting that MSCs exert an inhibitory effect downstream of the receptor level. We analyzed cytokine profiles of PBLs co-cultured with MSCs. MSCs increased interleukin (IL)-2 and soluble IL-2 receptor in mixed lymphocyte cultures (MLCs), while IL-2 and IL-2R decreased in phytohemagglutinin (PHA)-stimulated PBL cultures. MSCs inhibited IL-2 induced proliferation, without absorbing IL-2. IL-10 levels increased in MLCs co-cultured with 10% MSCs, while the levels were not affected in PHA cultures. In MLCs inhibited by MSCs, antibodies against IL-10 further suppressed proliferation but had no effect in PHA cultures. Addition of indomethacin, an inhibitor of prostaglandin-synthesis, restored part of the inhibition by MSCs in PHA cultures. However, indomethacin did not affect MSC-induced inhibition in MLCs. To conclude, our data indicate that MSC-induced suppression is a complex mechanism affecting IL-2 and IL-10 signaling and may function differently, depending on T-cell stimuli. Prostaglandins are important in the inhibition by MSCs when the T cells were activated by PHA, but not alloantigens

  2. Inhibition of histamine and eicosanoid release from dispersed human lung cells in vitro by quinotolast.

    Science.gov (United States)

    Okayama, Y; Hiroi, J; Lau, L C; Church, M K

    1995-12-01

    We have examined the effects of a new anti-allergic drug, quinotolast [sodium 5-(4-oxo-1-phenoxy-4H-quinolizine-3-carboxamido) yetrazolate monohydrate], in inhibiting the release of histamine and the generation of leukotriene (LT) C4 and prostaglandin (PG) D2 from dispersed human lung cells and compared this with those of its active metabolite in the rat, hydroxy quinotolast, and reference drugs, tranilast and sodium cromoglycate (SCG). Quinotolast in the concentration range of 1-100 micrograms/ml inhibited histamine and LTC4 release in a concentration-dependent manner. The inhibitory effect of quinotolast on histamine release from dispersed lung cells was largely independent of the preincubation period, no tachyphylaxis being observed. Hydroxy quinotolast and tranilast showed a weak inhibition of histamine release only when the drugs were added to the cells simultaneously with anti-IgE challenge. Quinotolast, 100 micrograms/ml, and SCG, 1 mM, significantly inhibited PGD2 and LTC4 release. Quinotolast inhibited PGD2 release by 100% and LTC4 release by 54%, whereas SCG inhibited PDG2 release by 33% and LTC4 release by 100%. No cross-tachyphylaxis between quinotolast and SCG was observed. The results demonstrated that quinotolast showed a significant inhibition of inflammatory mediators from human dispersed lung cells, suggesting that quinotolast is a good candidate for a clinical anti-allergic drug.

  3. Dihydroartemisinin inhibits the human erythroid cell differentiation by altering the cell cycle

    International Nuclear Information System (INIS)

    Finaurini, Sara; Basilico, Nicoletta; Corbett, Yolanda; D’Alessandro, Sarah; Parapini, Silvia; Olliaro, Piero; Haynes, Richard K.; Taramelli, Donatella

    2012-01-01

    Artemisinin derivatives such as dihydroartemisinin (DHA) induce significant depletion of early embryonic erythroblasts in animal models. We have reported previously that DHA specifically targets pro-erythroblasts and basophilic erythroblasts, when human CD34+ stem cells are differentiated toward the erythroid lineage, indicating that a window of susceptibility to artemisinins may exist also in human developmental erythropoiesis during pregnancy. To better investigate the toxicity of artemisinin derivatives, the structure–activity relationship was evaluated against the K562 leukaemia cell line, used as a model for differentiating early human erythroblasts. All artemisinins derivatives, except deoxyartemisinin, inhibited both spontaneous and induced erythroid differentiation, confirming that the peroxide bridge is responsible for the erythro-toxicity. On the contrary, cell growth was markedly reduced by DHA, artemisone and artesunate but not by artemisinin, 10-deoxoartemisinin or deoxy-artemisinin. The substituent at position C-10 is responsible only for the anti-proliferative effect, since 10-deoxoartemisinin did not reduce cell growth but arrested the differentiation of K562 cells. In particular, the results showed that DHA resulted the most potent and rapidly acting compound of the drug family, causing (i) the decreased expression of GpA surface receptors and the down regulation the γ-globin gene; (ii) the alteration of S phase of cell cycle and (iii) the induction of programmed cell death of early erythroblasts in a dose dependent manner within 24 h. In conclusion, these findings confirm that the active metabolite DHA is responsible for the erythro-toxicity of most of artemisinins used in therapy. Thus, as long as no further clinical data are available, current WHO recommendations of avoiding malaria treatment with artemisinins during the first trimester of pregnancy remain valid.

  4. CXCL10 can inhibit endothelial cell proliferation independently of CXCR3.

    Directory of Open Access Journals (Sweden)

    Gabriele S V Campanella

    2010-09-01

    Full Text Available CXCL10 (or Interferon-inducible protein of 10 kDa, IP-10 is an interferon-inducible chemokine with potent chemotactic activity on activated effector T cells and other leukocytes expressing its high affinity G protein-coupled receptor CXCR3. CXCL10 is also active on other cell types, including endothelial cells and fibroblasts. The mechanisms through which CXCL10 mediates its effects on non-leukocytes is not fully understood. In this study, we focus on the anti-proliferative effect of CXCL10 on endothelial cells, and demonstrate that CXCL10 can inhibit endothelial cell proliferation in vitro independently of CXCR3. Four main findings support this conclusion. First, primary mouse endothelial cells isolated from CXCR3-deficient mice were inhibited by CXCL10 as efficiently as wildtype endothelial cells. We also note that the proposed alternative splice form CXCR3-B, which is thought to mediate CXCL10's angiostatic activity, does not exist in mice based on published mouse CXCR3 genomic sequences as an in-frame stop codon would terminate the proposed CXCR3-B splice variant in mice. Second, we demonstrate that human umbilical vein endothelial cells and human lung microvascular endothelial cells that were inhibited by CXL10 did not express CXCR3 by FACS analysis. Third, two different neutralizing CXCR3 antibodies did not inhibit the anti-proliferative effect of CXCL10. Finally, fourth, utilizing a panel of CXCL10 mutants, we show that the ability to inhibit endothelial cell proliferation correlates with CXCL10's glycosaminoglycan binding affinity and not with its CXCR3 binding and signaling. Thus, using a very defined system, we show that CXCL10 can inhibit endothelial cell proliferation through a CXCR3-independent mechanism.

  5. Cyclooxygenase-2 Inhibition Enhances Proliferation of NKT Cells Derived from Patients with Laryngeal Cancer.

    Science.gov (United States)

    Klatka, Janusz; Grywalska, Ewelina; Hymos, Anna; Guz, Małgorzata; Polberg, Krzysztof; Roliński, Jacek; Stepulak, Andrzej

    2017-08-01

    The aim of this study was to analyze whether inhibition of cyclooxygenase-2 by celecoxib and the subsequent enhancement in the proliferation of natural killer T (NKT) cells could play a role in dendritic cell (DC)-based laryngeal cancer (LC) immunotherapy. Peripheral blood mononuclear cells were obtained from 48 male patients diagnosed with LC and 30 control patients without cancer disease. Neoplastic cell lysate preparations were made from cancer tissues obtained after surgery and used for in vitro DCs generation. NKT cells proliferation assay was performed based on 3 H-thymidine incorporation assay. An increased proliferation of NKT cells was obtained from control patients compared to NKT cells obtained from LC patients regardless of the type of stimulation or treatment. In the patient group diagnosed with LC, COX-2 inhibition resulted in a significantly enhanced proliferation of NKT cells when stimulated with autologous DCs than NKT cells stimulated with DCs without COX-2 inhibition. These correlations were not present in the control group. Higher proliferation rate of NKT cells was also observed in non-metastatic and highly differentiated LC, which was independent of the type of stimulation or treatment. COX-2 inhibition could be regarded as immunotherapy-enhancing tool in patients with LC. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

  6. In vitro developmental toxicity test detects inhibition of stem cell differentiation by silica nanoparticles

    International Nuclear Information System (INIS)

    Park, Margriet V.D.Z.; Annema, Wijtske; Salvati, Anna; Lesniak, Anna; Elsaesser, Andreas; Barnes, Clifford; McKerr, George; Howard, C. Vyvyan; Lynch, Iseult; Dawson, Kenneth A.; Piersma, Aldert H.; Jong, Wim H. de

    2009-01-01

    While research into the potential toxic properties of nanomaterials is now increasing, the area of developmental toxicity has remained relatively uninvestigated. The embryonic stem cell test is an in vitro screening assay used to investigate the embryotoxic potential of chemicals by determining their ability to inhibit differentiation of embryonic stem cells into spontaneously contracting cardiomyocytes. Four well characterized silica nanoparticles of various sizes were used to investigate whether nanomaterials are capable of inhibition of differentiation in the embryonic stem cell test. Nanoparticle size distributions and dispersion characteristics were determined before and during incubation in the stem cell culture medium by means of transmission electron microscopy (TEM) and dynamic light scattering. Mouse embryonic stem cells were exposed to silica nanoparticles at concentrations ranging from 1 to 100 μg/ml. The embryonic stem cell test detected a concentration dependent inhibition of differentiation of stem cells into contracting cardiomyocytes by two silica nanoparticles of primary size 10 (TEM 11) and 30 (TEM 34) nm while two other particles of primary size 80 (TEM 34) and 400 (TEM 248) nm had no effect up to the highest concentration tested. Inhibition of differentiation of stem cells occurred below cytotoxic concentrations, indicating a specific effect of the particles on the differentiation of the embryonic stem cells. The impaired differentiation of stem cells by such widely used particles warrants further investigation into the potential of these nanoparticles to migrate into the uterus, placenta and embryo and their possible effects on embryogenesis.

  7. Glycolysis inhibition inactivates ABC transporters to restore drug sensitivity in malignant cells.

    Directory of Open Access Journals (Sweden)

    Ayako Nakano

    Full Text Available Cancer cells eventually acquire drug resistance largely via the aberrant expression of ATP-binding cassette (ABC transporters, ATP-dependent efflux pumps. Because cancer cells produce ATP mostly through glycolysis, in the present study we explored the effects of inhibiting glycolysis on the ABC transporter function and drug sensitivity of malignant cells. Inhibition of glycolysis by 3-bromopyruvate (3BrPA suppressed ATP production in malignant cells, and restored the retention of daunorubicin or mitoxantrone in ABC transporter-expressing, RPMI8226 (ABCG2, KG-1 (ABCB1 and HepG2 cells (ABCB1 and ABCG2. Interestingly, although side population (SP cells isolated from RPMI8226 cells exhibited higher levels of glycolysis with an increased expression of genes involved in the glycolytic pathway, 3BrPA abolished Hoechst 33342 exclusion in SP cells. 3BrPA also disrupted clonogenic capacity in malignant cell lines including RPMI8226, KG-1, and HepG2. Furthermore, 3BrPA restored cytotoxic effects of daunorubicin and doxorubicin on KG-1 and RPMI8226 cells, and markedly suppressed subcutaneous tumor growth in combination with doxorubicin in RPMI8226-implanted mice. These results collectively suggest that the inhibition of glycolysis is able to overcome drug resistance in ABC transporter-expressing malignant cells through the inactivation of ABC transporters and impairment of SP cells with enhanced glycolysis as well as clonogenic cells.

  8. IL-15 protects NKT cells from inhibition by tumor-associated macrophages and enhances antimetastatic activity

    Science.gov (United States)

    Liu, Daofeng; Song, Liping; Wei, Jie; Courtney, Amy N.; Gao, Xiuhua; Marinova, Ekaterina; Guo, Linjie; Heczey, Andras; Asgharzadeh, Shahab; Kim, Eugene; Dotti, Gianpietro; Metelitsa, Leonid S.

    2012-01-01

    Vα24-invariant NKT cells inhibit tumor growth by targeting tumor-associated macrophages (TAMs). Tumor progression therefore requires that TAMs evade NKT cell activity through yet-unknown mechanisms. Here we report that a subset of cells in neuroblastoma (NB) cell lines and primary tumors expresses membrane-bound TNF-α (mbTNF-α). These proinflammatory tumor cells induced production of the chemokine CCL20 from TAMs via activation of the NF-κB signaling pathway, an effect that was amplified in hypoxia. Flow cytometry analyses of human primary NB tumors revealed selective accumulation of CCL20 in TAMs. Neutralization of the chemokine inhibited in vitro migration of NKT cells toward tumor-conditioned hypoxic monocytes and localization of NKT cells to NB grafts in mice. We also found that hypoxia impaired NKT cell viability and function. Thus, CCL20-producing TAMs served as a hypoxic trap for tumor-infiltrating NKT cells. IL-15 protected antigen-activated NKT cells from hypoxia, and transgenic expression of IL-15 in adoptively transferred NKT cells dramatically enhanced their antimetastatic activity in mice. Thus, tumor-induced chemokine production in hypoxic TAMs and consequent chemoattraction and inhibition of NKT cells represents a mechanism of immune escape that can be reversed by adoptive immunotherapy with IL-15–transduced NKT cells. PMID:22565311

  9. IL-15 protects NKT cells from inhibition by tumor-associated macrophages and enhances antimetastatic activity.

    Science.gov (United States)

    Liu, Daofeng; Song, Liping; Wei, Jie; Courtney, Amy N; Gao, Xiuhua; Marinova, Ekaterina; Guo, Linjie; Heczey, Andras; Asgharzadeh, Shahab; Kim, Eugene; Dotti, Gianpietro; Metelitsa, Leonid S

    2012-06-01

    Vα24-invariant NKT cells inhibit tumor growth by targeting tumor-associated macrophages (TAMs). Tumor progression therefore requires that TAMs evade NKT cell activity through yet-unknown mechanisms. Here we report that a subset of cells in neuroblastoma (NB) cell lines and primary tumors expresses membrane-bound TNF-α (mbTNF-α). These proinflammatory tumor cells induced production of the chemokine CCL20 from TAMs via activation of the NF-κB signaling pathway, an effect that was amplified in hypoxia. Flow cytometry analyses of human primary NB tumors revealed selective accumulation of CCL20 in TAMs. Neutralization of the chemokine inhibited in vitro migration of NKT cells toward tumor-conditioned hypoxic monocytes and localization of NKT cells to NB grafts in mice. We also found that hypoxia impaired NKT cell viability and function. Thus, CCL20-producing TAMs served as a hypoxic trap for tumor-infiltrating NKT cells. IL-15 protected antigen-activated NKT cells from hypoxia, and transgenic expression of IL-15 in adoptively transferred NKT cells dramatically enhanced their antimetastatic activity in mice. Thus, tumor-induced chemokine production in hypoxic TAMs and consequent chemoattraction and inhibition of NKT cells represents a mechanism of immune escape that can be reversed by adoptive immunotherapy with IL-15-transduced NKT cells.

  10. High Glucose Inhibits Neural Stem Cell Differentiation Through Oxidative Stress and Endoplasmic Reticulum Stress.

    Science.gov (United States)

    Chen, Xi; Shen, Wei-Bin; Yang, Penghua; Dong, Daoyin; Sun, Winny; Yang, Peixin

    2018-06-01

    Maternal diabetes induces neural tube defects by suppressing neurogenesis in the developing neuroepithelium. Our recent study further revealed that high glucose inhibited embryonic stem cell differentiation into neural lineage cells. However, the mechanism whereby high glucose suppresses neural differentiation is unclear. To investigate whether high glucose-induced oxidative stress and endoplasmic reticulum (ER) stress lead to the inhibition of neural differentiation, the effect of high glucose on neural stem cell (the C17.2 cell line) differentiation was examined. Neural stem cells were cultured in normal glucose (5 mM) or high glucose (25 mM) differentiation medium for 3, 5, and 7 days. High glucose suppressed neural stem cell differentiation by significantly decreasing the expression of the neuron marker Tuj1 and the glial cell marker GFAP and the numbers of Tuj1 + and GFAP + cells. The antioxidant enzyme superoxide dismutase mimetic Tempol reversed high glucose-decreased Tuj1 and GFAP expression and restored the numbers of neurons and glial cells differentiated from neural stem cells. Hydrogen peroxide treatment imitated the inhibitory effect of high glucose on neural stem cell differentiation. Both high glucose and hydrogen peroxide triggered ER stress, whereas Tempol blocked high glucose-induced ER stress. The ER stress inhibitor, 4-phenylbutyrate, abolished the inhibition of high glucose or hydrogen peroxide on neural stem cell differentiation. Thus, oxidative stress and its resultant ER stress mediate the inhibitory effect of high glucose on neural stem cell differentiation.

  11. Mechanisms involved in growth inhibition induced by clofibrate in hepatoma cells

    International Nuclear Information System (INIS)

    Muzio, Giuliana; Maggiora, Marina; Trombetta, Antonella; Martinasso, Germana; Reffo, Patrizia; Colombatto, Sebastiano; Canuto, Rosa Angela

    2003-01-01

    Low concentrations of some peroxisome proliferators have been found to decrease apoptosis in rat liver cells, whereas higher but pharmacological concentrations have been found to inhibit cell proliferation or to induce apoptosis in human and rat hepatoma cells. The highly deviated JM2 rat hepatoma cell line was used to examine the mechanisms underlying the inhibitory effect on cell proliferation. Clofibrate chiefly inhibited cell proliferation in these cells. Parallel to the decrease in cell proliferation there was an increase of peroxisome proliferator activated receptor (PPAR) gamma and of protein phosphatase 2A, whose importance was confirmed, respectively, by using antisense oliginucleotides (AS-ODN) or okadaic acid. The increase of protein phosphatase 2A induced by PPARgamma caused a decrease of MAPK, an intracellular signaling transduction pathway, as shown by evaluation of Erk1,2 and c-myc. In light of these results, clofibrate, like conventional synthetic ligands of PPARgamma, may be regarded as a possible prototype anti-tumour drug

  12. Inhibition of NF-κB in Tumor Cells Exacerbates Immune Cell Activation Following Photodynamic Therapy

    Science.gov (United States)

    Broekgaarden, Mans; Kos, Milan; Jurg, Freek A.; van Beek, Adriaan A.; van Gulik, Thomas M.; Heger, Michal

    2015-01-01

    Although photodynamic therapy (PDT) yields very good outcomes in numerous types of superficial solid cancers, some tumors respond suboptimally to PDT. Novel treatment strategies are therefore needed to enhance the efficacy in these therapy-resistant tumors. One of these strategies is to combine PDT with inhibitors of PDT-induced survival pathways. In this respect, the transcription factor nuclear factor κB (NF-κB) has been identified as a potential pharmacological target, albeit inhibition of NF-κB may concurrently dampen the subsequent anti-tumor immune response required for complete tumor eradication and abscopal effects. In contrast to these postulations, this study demonstrated that siRNA knockdown of NF-κB in murine breast carcinoma (EMT-6) cells increased survival signaling in these cells and exacerbated the inflammatory response in murine RAW 264.7 macrophages. These results suggest a pro-death and immunosuppressive role of NF-κB in PDT-treated cells that concurs with a hyperstimulated immune response in innate immune cells. PMID:26307977

  13. Ethanol inhibits B16-BL6 melanoma metastasis and cell phenotypes associated with metastasis.

    Science.gov (United States)

    Kushiro, Kyoko; Núñez, Nomelí P

    2012-01-01

    Every year, approximately 68,000 new cases of malignant melanoma are diagnosed in the US. Ethanol consumption inhibits metastasis of melanoma in mice, but the mechanism is not well understood. C57BL/6J ob/+ mice, given either water or 20% ethanol, were injected intravenously with B16-BL6 melanoma cells to determine pulmonary metastasis. The effects of ethanol on cell phenotypes and markers of the epithelial-to-mesenchymal transition were determined in cell culture. In mice, ethanol consumption inhibited experimental pulmonary metastasis. This inhibition was associated with decreased body weight, and levels of systemic leptin, and insulin. In cell culture, ethanol inhibited B16-BL6 cell motility, invasion, and anchorage-independent growth. Additionally, ethanol reduced Snai1 expression and increased E-cadherin expression. Lastly, ethanol increased the expression of Kiss1 metastasis-suppressor and the metastasis suppressor Nm23/nucleoside diphosphate kinase. In both animal and in cell culture conditions, ethanol inhibited the metastatic ability of B16-BL6 melanoma cells.

  14. BET bromodomain inhibition rescues erythropoietin differentiation of human erythroleukemia cell line UT7

    International Nuclear Information System (INIS)

    Goupille, Olivier; Penglong, Tipparat; Lefèvre, Carine; Granger, Marine; Kadri, Zahra; Fucharoen, Suthat; Maouche-Chrétien, Leila; Leboulch, Philippe; Chrétien, Stany

    2012-01-01

    Highlights: ► UT7 erythroleukemia cells are known to be refractory to differentiate. ► Brief JQ1 treatment initiates the first steps of erythroid differentiation program. ► Engaged UT7 cells then maturate in the presence of erythropoietin. ► Sustained JQ1 treatment inhibits both proliferation and erythroid differentiation. -- Abstract: Malignant transformation is a multistep process requiring oncogenic activation, promoting cellular proliferation, frequently coupled to inhibition of terminal differentiation. Consequently, forcing the reengagement of terminal differentiation of transformed cells coupled or not with an inhibition of their proliferation is a putative therapeutic approach to counteracting tumorigenicity. UT7 is a human leukemic cell line able to grow in the presence of IL3, GM-CSF and Epo. This cell line has been widely used to study Epo-R/Epo signaling pathways but is a poor model for erythroid differentiation. We used the BET bromodomain inhibition drug JQ1 to target gene expression, including that of c-Myc. We have shown that only 2 days of JQ1 treatment was required to transitory inhibit Epo-induced UT7 proliferation and to restore terminal erythroid differentiation. This study highlights the importance of a cellular erythroid cycle break mediated by c-Myc inhibition before initiation of the erythropoiesis program and describes a new model for BET bromodomain inhibitor drug application.

  15. BET bromodomain inhibition rescues erythropoietin differentiation of human erythroleukemia cell line UT7

    Energy Technology Data Exchange (ETDEWEB)

    Goupille, Olivier [CEA, Institute of Emerging Diseases and Innovative Therapies, Fontenay-aux-Roses (France); UMR INSERM U.962, University Paris XI, CEA, Fontenay-aux-Roses (France); Penglong, Tipparat [CEA, Institute of Emerging Diseases and Innovative Therapies, Fontenay-aux-Roses (France); UMR INSERM U.962, University Paris XI, CEA, Fontenay-aux-Roses (France); Thalassemia Research Center and Department of Clinical Pathology, Faculty of Medicine, Ramathibodi Hospital, Mahidol University (Thailand); Lefevre, Carine; Granger, Marine; Kadri, Zahra [CEA, Institute of Emerging Diseases and Innovative Therapies, Fontenay-aux-Roses (France); UMR INSERM U.962, University Paris XI, CEA, Fontenay-aux-Roses (France); Fucharoen, Suthat [Thalassemia Research Center and Department of Clinical Pathology, Faculty of Medicine, Ramathibodi Hospital, Mahidol University (Thailand); Maouche-Chretien, Leila [CEA, Institute of Emerging Diseases and Innovative Therapies, Fontenay-aux-Roses (France); UMR INSERM U.962, University Paris XI, CEA, Fontenay-aux-Roses (France); Leboulch, Philippe [CEA, Institute of Emerging Diseases and Innovative Therapies, Fontenay-aux-Roses (France); UMR INSERM U.962, University Paris XI, CEA, Fontenay-aux-Roses (France); Genetics Division, Department of Medicine, Brigham and Women' s Hospital and Harvard Medical School, Boston, MA (United States); Chretien, Stany, E-mail: stany.chretien@cea.fr [CEA, Institute of Emerging Diseases and Innovative Therapies, Fontenay-aux-Roses (France); UMR INSERM U.962, University Paris XI, CEA, Fontenay-aux-Roses (France)

    2012-12-07

    Highlights: Black-Right-Pointing-Pointer UT7 erythroleukemia cells are known to be refractory to differentiate. Black-Right-Pointing-Pointer Brief JQ1 treatment initiates the first steps of erythroid differentiation program. Black-Right-Pointing-Pointer Engaged UT7 cells then maturate in the presence of erythropoietin. Black-Right-Pointing-Pointer Sustained JQ1 treatment inhibits both proliferation and erythroid differentiation. -- Abstract: Malignant transformation is a multistep process requiring oncogenic activation, promoting cellular proliferation, frequently coupled to inhibition of terminal differentiation. Consequently, forcing the reengagement of terminal differentiation of transformed cells coupled or not with an inhibition of their proliferation is a putative therapeutic approach to counteracting tumorigenicity. UT7 is a human leukemic cell line able to grow in the presence of IL3, GM-CSF and Epo. This cell line has been widely used to study Epo-R/Epo signaling pathways but is a poor model for erythroid differentiation. We used the BET bromodomain inhibition drug JQ1 to target gene expression, including that of c-Myc. We have shown that only 2 days of JQ1 treatment was required to transitory inhibit Epo-induced UT7 proliferation and to restore terminal erythroid differentiation. This study highlights the importance of a cellular erythroid cycle break mediated by c-Myc inhibition before initiation of the erythropoiesis program and describes a new model for BET bromodomain inhibitor drug application.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  17. LHRH inhibits [3H]thymidine incorporation by pituitary cells cultured IN VITRO

    International Nuclear Information System (INIS)

    Stepien, H.

    1981-01-01

    The effects of two synthetic neuropeptides, LHRH and neurotensin, on tritiated thymidine uptake by dispersed anterior pituitary cells were investigated. It was found that LHRH but not neurotensin (at concentrations between 10 -7 - 10 -11 M) inhibits incorporation of [ 3 H]thymidine into DNA of pituitary cell nuclei, in a dose-dependent manner. These results indicate that LHRH can regulate not only secretory activity of the gonadotrophic cells but also can be involved in the control of anterior pituitary cell replication

  18. Invariant NKT cells regulate experimental autoimmune uveitis through inhibition of Th17 differentiation.

    Science.gov (United States)

    Oh, Keunhee; Byoun, Ok-Jin; Ham, Don-Il; Kim, Yon Su; Lee, Dong-Sup

    2011-02-01

    Although NKT cells have been implicated in diverse immunomodulatory responses, the effector mechanisms underlying the NKT cell-mediated regulation of pathogenic T helper cells are not well understood. Here, we show that invariant NKT cells inhibited the differentiation of CD4(+) T cells into Th17 cells both in vitro and in vivo. The number of IL-17-producing CD4(+) T cells was reduced following co-culture with purified NK1.1(+) TCR(+) cells from WT, but not from CD1d(-/-) or Jα18(-/-) , mice. Co-cultured NKT cells from either cytokine-deficient (IL-4(-/-) , IL-10(-/-) , or IFN-γ(-/-) ) or WT mice efficiently inhibited Th17 differentiation. The contact-dependent mechanisms of NKT cell-mediated regulation of Th17 differentiation were confirmed using transwell co-culture experiments. On the contrary, the suppression of Th1 differentiation was dependent on IL-4 derived from the NKT cells. The in vivo regulatory capacity of NKT cells on Th17 cells was confirmed using an experimental autoimmune uveitis model induced with human IRBP(1-20) (IRBP, interphotoreceptor retinoid-binding protein) peptide. NKT cell-deficient mice (CD1d(-/-) or Jα18(-/-) ) demonstrated an increased disease severity, which was reversed by the transfer of WT or cytokine-deficient (IL-4(-/-) , IL-10(-/-) , or IFN-γ(-/-) ) NKT cells. Our results indicate that invariant NKT cells inhibited autoimmune uveitis predominantly through the cytokine-independent inhibition of Th17 differentiation. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Saccharomyces boulardii inhibits lipopolysaccharide-induced activation of human dendritic cells and T cell proliferation

    Science.gov (United States)

    Thomas, S; Przesdzing, I; Metzke, D; Schmitz, J; Radbruch, A; Baumgart, D C

    2009-01-01

    Saccharomyces boulardii (Sb) is a probiotic yeast preparation that has demonstrated efficacy in inflammatory and infectious disorders of the gastrointestinal tract in controlled clinical trials. Although patients clearly benefit from treatment with Sb, little is known on how Sb unfolds its anti-inflammatory properties in humans. Dendritic cells (DC) balance tolerance and immunity and are involved critically in the control of T cell activation. Thus, they are believed to have a pivotal role in the initiation and perpetuation of chronic inflammatory disorders, not only in the gut. We therefore decided to investigate if Sb modulates DC function. Culture of primary (native, non-monocyte-derived) human myeloid CD1c+CD11c+CD123– DC (mDC) in the presence of Sb culture supernatant (active component molecular weight < 3 kDa, as evaluated by membrane partition chromatography) reduced significantly expression of the co-stimulatory molecules CD40 and CD80 (P < 0·01) and the DC mobilization marker CC-chemokine receptor CCR7 (CD197) (P < 0·001) induced by the prototypical microbial antigen lipopolysaccharide (LPS). Moreover, secretion of key proinflammatory cytokines such as tumour necrosis factor-α and interleukin (IL)-6 were notably reduced, while the secretion of anti-inflammatory IL-10 increased. Finally, Sb supernatant inhibited the proliferation of naive T cells in a mixed lymphocyte reaction with mDC. In summary, our data suggest that Sb may exhibit part of its anti-inflammatory potential through modulation of DC phenotype, function and migration by inhibition of their immune response to bacterial microbial surrogate antigens such as LPS. PMID:19161443

  20. Inhibition of glucose turnover by 3-bromopyruvate counteracts pancreatic cancer stem cell features and sensitizes cells to gemcitabine

    OpenAIRE

    Isayev, Orkhan; Rausch, Vanessa; Bauer, Nathalie; Liu, Li; Fan, Pei; Zhang, Yiyao; Gladkich, Jury; Nwaeburu, Clifford C.; Mattern, Jürgen; Mollenhauer, Martin; Rückert, Felix; Zach, Sebastian; Haberkorn, Uwe; Gross, Wolfgang; Schönsiegel, Frank

    2014-01-01

    According to the cancer stem cell (CSC) hypothesis, the aggressive growth and early metastasis of pancreatic ductal adenocarcinoma (PDA) is due to the activity of CSCs, which are not targeted by current therapies. Otto Warburg suggested that the growth of cancer cells is driven by a high glucose metabolism. Here, we investigated whether glycolysis inhibition targets CSCs and thus may enhance therapeutic efficacy. Four established and 3 primary PDA cell lines, non-malignant cells, and 3 patien...

  1. Inhibition of DNA synthesis and radiosensitization effects of thalidomide on esophageal carcinoma TE1 cells

    International Nuclear Information System (INIS)

    Yu Jingping; Sun Suping; Sun Zhiqiang; Sun Meiling; Liu Fenju

    2010-01-01

    Objective: To explore the radiosensitization effect of thalidomide combined with X-ray on esophageal carcinoma TE1 cells. Methods: Cell scratch assay was used to detect the inhibition ability of different concentration of Thalidomide on cell invasion and metastasis. H 3 -TdR incorporation assay was used to investigate the inhibition of DNA synthesis in TE1 cells by treated with Thalidomide singly or combination with X-rays. The colony formation assay was used to analyze the radiosensitization of Thalidomide effect on TE1 cells. Results: Thalidomide had obvious inhibition effect on TE1 cell metastasis, DNA synthesis and colony formation, which were correlated with drug concentration. The values D 0 , D q and SF 2 in TE1 cells were gradually decreased with thalidomide concentration increased. When the concentration of thalidomide was 100μg/ml, the SER D 0 and SER D 0 and SER D q were (1.4±0.2) and (1.5±0.1), respectively, While the concentration of thalidomide was 150 μg/ml, the SER D 0 and SER D q were (1.5±0.2) and (1.8±0.2), respectively. Conclusions: Thalidomide could inhibit TE1 cell invasion, metastasis, DNA synthesis, and significantly enhance the radiosensitizing effect on esophageal carcinoma TE1 cells. (authors)

  2. CD83 Antibody Inhibits Human B Cell Responses to Antigen as well as Dendritic Cell-Mediated CD4 T Cell Responses.

    Science.gov (United States)

    Wong, Kuan Y; Baron, Rebecca; Seldon, Therese A; Jones, Martina L; Rice, Alison M; Munster, David J

    2018-05-15

    Anti-CD83 Ab capable of Ab-dependent cellular cytotoxicity can deplete activated CD83 + human dendritic cells, thereby inhibiting CD4 T cell-mediated acute graft-versus-host disease. As CD83 is also expressed on the surface of activated B lymphocytes, we hypothesized that anti-CD83 would also inhibit B cell responses to stimulation. We found that anti-CD83 inhibited total IgM and IgG production in vitro by allostimulated human PBMC. Also, Ag-specific Ab responses to immunization of SCID mice xenografted with human PBMC were inhibited by anti-CD83 treatment. This inhibition occurred without depletion of all human B cells because anti-CD83 lysed activated CD83 + B cells by Ab-dependent cellular cytotoxicity and spared resting (CD83 - ) B cells. In cultured human PBMC, anti-CD83 inhibited tetanus toxoid-stimulated B cell proliferation and concomitant dendritic cell-mediated CD4 T cell proliferation and expression of IFN-γ and IL-17A, with minimal losses of B cells (80% of B cells but had no effect on CD4 T cell proliferation and cytokine expression. By virtue of the ability of anti-CD83 to selectively deplete activated, but not resting, B cells and dendritic cells, with the latter reducing CD4 T cell responses, anti-CD83 may be clinically useful in autoimmunity and transplantation. Advantages might include inhibited expansion of autoantigen- or alloantigen-specific B cells and CD4 T cells, thus preventing further production of pathogenic Abs and inflammatory cytokines while preserving protective memory and regulatory cells. Copyright © 2018 by The American Association of Immunologists, Inc.

  3. Inhibition of cathepsin X enzyme influences the immune response of THP-1 cells and dendritic cells infected with Helicobacter pylori

    International Nuclear Information System (INIS)

    Skvarc, Miha; Stubljar, David; Kopitar, Andreja Natasa; Jeverica, Samo; Tepes, Bojan; Kos, Janko; Ihan, Alojz

    2013-01-01

    The immune response to Helicobacter pylori importantly determines the outcome of infection as well as the success of eradication therapy. We demonstrate the role of a cysteine protease cathepsin X in the immune response to H. pylori infection. We analysed how the inhibition of cathepsin X influenced the immune response in experiments when THP-1 cells or dendritic cells isolated from patients were stimulated with 48 strains of H. pylori isolated from gastric biopsy samples of patients which had problems with the eradication of bacteria. The experiments, performed with the help of a flow cytometer, showed that the expression of Toll-like receptors (TLRs), especially TLR-4 molecules, on the membranes of THP-1 cells or dendritic cells was higher when we stimulated cells with H. pylori together with inhibitor of cathepsin X 2F12 compared to THP-1 cells or dendritic cells stimulated with H. pylori only, and also in comparison with negative control samples. We also demonstrated that when we inhibited the action of cathepsin X in THP-1 cells, the concentrations of pro-inflammatory cytokines were lower than when THP-1 cell were stimulated with H. pylori only. We demonstrated that inhibition of cathepsin X influences the internalization of TLR-2 and TLR-4. TLR-2 and TLR-4 redistribution to intra-cytoplasmic compartments is hampered if cathepsin X is blocked. The beginning of a successful immune response against H. pylori in the case of inhibition of cathepsin X is delayed

  4. Melatonin inhibits proliferation and invasion via repression of miRNA-155 in glioma cells.

    Science.gov (United States)

    Gu, Junyi; Lu, Zhongsheng; Ji, Chenghong; Chen, Yuchao; Liu, Yuzhao; Lei, Zhe; Wang, Longqiang; Zhang, Hong-Tao; Li, Xiangdong

    2017-09-01

    Melatonin, an indolamine mostly synthesized in the pineal gland, exerts the anti-cancer effect by various mechanisms in glioma cells. Our previous study showed that miR-155 promoted glioma cell proliferation and invasion. However, the question of whether melatonin may inhibit glioma by regulating miRNAs has not yet been addressed. In this study, we found that melatonin (100μM, 1μM and 1nM) significantly inhibited the expression of miR-155 in human glioma cell lines U87, U373 and U251. Especially, the lowest expression of miR-155 was detected in 1μM melatonin-treated glioma cells. Melatonin (1μM) inhibits cell proliferation of U87 by promoting cell apoptosis. Nevertheless, melatonin had no effect on cell cycle distribution of U87 cells. Moreover, U87 cells treated with 1μM melatonin presented significantly lower migration and invasion ability when compared with control cells. Importantly, melatonin inhibited c-MYB expression, and c-MYB knockdown reduced miR-155 expression and migration and invasion in U87 cells. Taken together, for the first time, our findings show that melatonin inhibits miR-155 expression and thereby represses glioma cell proliferation, migration and invasion, and suggest that melatonin may downregulate the expression of miR-155 via repression of c-MYB. This will provide a theoretical basis for revealing the anti-glioma mechanisms of melatonin. Copyright © 2017. Published by Elsevier Masson SAS.

  5. In vitro atrazine-exposure inhibits human natural killer cell lytic granule release

    International Nuclear Information System (INIS)

    Rowe, Alexander M.; Brundage, Kathleen M.; Barnett, John B.

    2007-01-01

    The herbicide atrazine is a known immunotoxicant and an inhibitor of human natural killer (NK) cell lytic function. The precise changes in NK cell lytic function following atrazine exposure have not been fully elucidated. The current study identifies the point at which atrazine exerts its affect on the stepwise process of human NK cell-mediated lyses of the K562 target cell line. Using intracellular staining of human peripheral blood lymphocytes, it was determined that a 24-h in vitro exposure to atrazine did not decrease the level of NK cell lytic proteins granzyme A, granzyme B or perforin. Thus, it was hypothesized that atrazine exposure was inhibiting the ability of the NK cells to bind to the target cell and subsequently inhibit the release of lytic protein from the NK cell. To test this hypothesis, flow cytometry and fluorescent microscopy were employed to analyze NK cell-target cell co-cultures following atrazine exposure. These assays demonstrated no significant decrease in the level of target cell binding. However, the levels of NK intracellular lytic protein retained and the amount of lytic protein released were assessed following a 4-h incubation with K562 target cells. The relative level of intracellular lytic protein was 25-50% higher, and the amount of lytic protein released was 55-65% less in atrazine-treated cells than vehicle-treated cells following incubation with the target cells. These results indicate that ATR exposure inhibits the ability of NK cells to lyse target cells by blocking lytic granule release without affecting the ability of the NK cell to form stable conjugates with target cells

  6. Vitisin B, a resveratrol tetramer, inhibits migration through inhibition of PDGF signaling and enhancement of cell adhesiveness in cultured vascular smooth muscle cells

    International Nuclear Information System (INIS)

    Ong, Eng-Thaim; Hwang, Tsong-Long; Huang, Yu-Ling; Lin, Chwan-Fwu; Wu, Wen-Bin

    2011-01-01

    Vascular smooth muscle cells (VSMCs) play an important role in normal vessel formation and in the development and progression of cardiovascular diseases. Grape plants contain resveratrol monomer and oligomers and drinking of wine made from grape has been linked to 'French Paradox'. In this study we evaluated the effect of vitisin B, a resveratrol tetramer, on VSMC behaviors. Vitisin B inhibited basal and PDGF-induced VSMC migration. Strikingly, it did not inhibit VSMC proliferation but inversely enhanced cell cycle progression and proliferation. Among the tested resveratrol oligomers, vitisin B showed an excellent inhibitory activity and selectivity on PDGF signaling. The anti-migratory effect by vitisin B was due to direct inhibition on PDGF signaling but was independent of interference with PDGF binding to VSMCs. Moreover, the enhanced VSMC adhesiveness to matrix contributed to the anti-migratory effect by vitisin B. Fluorescence microscopy revealed an enhanced reorganization of actin cytoskeleton and redistribution of activated focal adhesion proteins from cytosol to the peripheral edge of the cell membrane. This was confirmed by the observation that enhanced adhesiveness was repressed by the Src inhibitor. Finally, among the effects elicited by vitisin B, only the inhibitory effect toward basal migration was partially through estrogen receptor activation. We have demonstrated here that a resveratrol tetramer exhibited dual but opposite actions on VSMCs, one is to inhibit VSMC migration and the other is to promote VSMC proliferation. The anti-migratory effect was through a potent inhibition on PDGF signaling and novel enhancement on cell adhesion. - Highlights: → Several resveratrol oligomers from grape plants are examined on VSMC behaviors. → Tetraoligomer vitisin B shows excellent inhibitory activity and selectivity. → It exerts dual but opposing actions: anti-migratory and pro-proliferative effects. → The anti-migratory effect results from anti

  7. PARTICULATE MATTER (PM) INHIBITS NEUROTROPHIN RELEASE FROM A549 CELLS

    Science.gov (United States)

    Several investigations have linked PM exposure to the exacerbation of allergic lung diseases. Many PM effects are mediated by cells within the lung including the airway epithelium, eosinophils, and lymphocytes. These cells also produce neurotophins such as NGF and/or express neur...

  8. Chloroquinone Inhibits Cell Proliferation and Induces Apoptosis in ...

    African Journals Online (AJOL)

    Purpose: To demonstrate the role of chloroquinone (CQ) in inducing apoptosis in HONE-1 and HNE-1, nasopharyngeal carcinoma (NPC) cell lines. Methods: Water-soluble tetrazolium salt (WST)-1 assay was used for the determination of cell proliferation while an inverted microscope was employed for the analysis of ...

  9. Induction of apoptosis and cell proliferation inhibition by paclitaxel in ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-02-18

    Feb 18, 2009 ... contribution of different forms of cell death to cancer development and treatment requires ... Killing malignant cells is the number one goal of almost all forms of cancer therapy in use today. In ..... Adoptive Immunotherapy in the Treatment of hASIPa-Overexpressed. Breast Cancer. Oncol. Res. 17: 59-68.

  10. Mevastatin-induced inhibition of cell growth in avocado suspension ...

    African Journals Online (AJOL)

    Cell suspension cultures were established using soft, friable callus derived from nucellar tissue of 'Hass' avocado (Persea americana Mill.) seed from fruit harvested 190 days after full bloom. Cell cultures were maintained in liquid medium supplemented with naphthalene acetic acid (NAA), isopentenyl adenine (iP) and ...

  11. Inhibition of telomerase activity and cell growth by free and ...

    African Journals Online (AJOL)

    found in some plants such as Punica granatum,. Terminalia catappa and Combretum molle [10]. It has inhibitory effect on different kinds of cancer cells including prostate and colon cancer cells. [11,12]. However, the in vivo instability of punicalagin has restricted its use in biomedical research [13]. Previous studies showed ...

  12. Inhibition of platelet-tumour cell interaction with ibrutinib reduces ...

    African Journals Online (AJOL)

    Methods: Human lung cancer cells A549 were treated with ibrutinib or DMSO. mRNA ... Given Btk is a critical molecular factor in B-cell receptor ... small interfering RNA (siRNA; Ribo-Bio, .... suppressing the growth of pancreatic ductal.

  13. Novel derivatives of aclacinomycin A block cancer cell migration through inhibition of farnesyl transferase.

    Science.gov (United States)

    Magi, Shigeyuki; Shitara, Tetsuo; Takemoto, Yasushi; Sawada, Masato; Kitagawa, Mitsuhiro; Tashiro, Etsu; Takahashi, Yoshikazu; Imoto, Masaya

    2013-03-01

    In the course of screening for an inhibitor of farnesyl transferase (FTase), we identified two compounds, N-benzyl-aclacinomycin A (ACM) and N-allyl-ACM, which are new derivatives of ACM. N-benzyl-ACM and N-allyl-ACM inhibited FTase activity with IC50 values of 0.86 and 2.93 μM, respectively. Not only ACM but also C-10 epimers of each ACM derivative failed to inhibit FTase. The inhibition of FTase by N-benzyl-ACM and N-allyl-ACM seems to be specific, because these two compounds did not inhibit geranylgeranyltransferase or geranylgeranyl pyrophosphate (GGPP) synthase up to 100 μM. In cultured A431 cells, N-benzyl-ACM and N-allyl-ACM also blocked both the membrane localization of H-Ras and activation of the H-Ras-dependent PI3K/Akt pathway. In addition, they inhibited epidermal growth factor (EGF)-induced migration of A431 cells. Thus, N-benzyl-ACM and N-allyl-ACM inhibited EGF-induced migration of A431 cells by inhibiting the farnesylation of H-Ras and subsequent H-Ras-dependent activation of the PI3K/Akt pathway.

  14. Analogue circuits simulation

    Energy Technology Data Exchange (ETDEWEB)

    Mendo, C

    1988-09-01

    Most analogue simulators have evolved from SPICE. The history and description of SPICE-like simulators are given. From a mathematical formulation of the electronic circuit the following analysis are possible: DC, AC, transient, noise, distortion, Worst Case and Statistical.

  15. Notch inhibition counteracts Paneth cell death in absence of caspase-8.

    Science.gov (United States)

    Jeon, M K; Kaemmerer, E; Schneider, U; Schiffer, M; Klaus, C; Hennings, J; Clahsen, T; Ackerstaff, T; Niggemann, M; Schippers, A; Longerich, T; Sellge, G; Trautwein, C; Wagner, N; Liedtke, C; Gassler, N

    2018-05-16

    Opposing activities of Notch and Wnt signaling regulate mucosal barrier homeostasis and differentiation of intestinal epithelial cells. Specifically, Wnt activity is essential for differentiation of secretory cells including Wnt3-producing Paneth cells, whereas Notch signaling strongly promotes generation of absorptive cells. Loss of caspase-8 in intestinal epithelium (casp8 ∆int ) is associated with fulminant epithelial necroptosis, severe Paneth cell death, secondary intestinal inflammation, and an increase in Notch activity. Here, we found that pharmacological Notch inhibition with dibenzazepine (DBZ) is able to essentially rescue the loss of Paneth cells, deescalate the inflammatory phenotype, and reduce intestinal permeability in casp8 ∆int mice. The secretory cell metaplasia in DBZ-treated casp8 ∆int animals is proliferative, indicating for Notch activities partially insensitive to gamma-secretase inhibition in a casp8 ∆int background. Our data suggest that casp8 acts in the intestinal Notch network.

  16. Chloroquine inhibits accessory cell presentation of soluble natural and synthetic protein antigens

    DEFF Research Database (Denmark)

    Buus, S; Werdelin, O

    1984-01-01

    We have studied the in vitro effect of the lysosomotrophic agent, chloroquine, on the presentation of soluble protein antigens by guinea pig accessory cells. Chloroquine inhibited the capacity of antigen-pulsed accessory cells to stimulate proliferation in appropriately primed T cells. The effect...... was time- and dose-dependent. A brief treatment solely of the accessory cells with the drug compromised their ability to stimulate primed T cells in a subsequent culture provided the accessory cells were treated with chloroquine before their exposure to the antigen. These results suggest that chloroquine...... acts on an early event in the antigen handling by accessory cells. Chloroquine is a well known inhibitor of lysosomal proteolysis, and it is likely that its effect on antigen presentation is caused by an inhibition of antigen degradation....

  17. ADAMTS1 inhibits lymphangiogenesis by attenuating phosphorylation of the lymphatic endothelial cell-specific VEGF receptor

    Energy Technology Data Exchange (ETDEWEB)

    Inagaki, Junko; Takahashi, Katsuyuki; Ogawa, Hiroko; Asano, Keiichi; Faruk Hatipoglu, Omer; Zeynel Cilek, Mehmet; Obika, Masanari; Ohtsuki, Takashi [Department of Molecular Biology and Biochemistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama (Japan); Hofmann, Matthias [Department of Dermatology, Venereology and Allergology, Goethe University, Frankfurt (Germany); Kusachi, Shozo [Department of Medical Technology, Okayama University Graduate School of Health Sciences, Okayama (Japan); Ninomiya, Yoshifumi [Department of Molecular Biology and Biochemistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama (Japan); Hirohata, Satoshi, E-mail: hirohas@cc.okayama-u.ac.jp [Department of Molecular Biology and Biochemistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama (Japan); International Center, Okayama University, Okayama (Japan)

    2014-05-01

    Angiogenesis and lymphangiogenesis play roles in malignant tumor progression, dissemination, and metastasis. ADAMTS1, a member of the matrix metalloproteinase family, is known to inhibit angiogenesis. Recombinant ADAMTS1 was shown to strongly inhibit angiogenesis. We investigated whether ADAMTS1 inhibited lymphangiogenesis in the present study. We examined cell proliferation and cell migration in normal human dermal lymphatic microvascular endothelial cells (HMVEC-dLy) transduced with or without adenoviral human ADAMTS1 gene therapy. We then examined the VEGFC/VEGFR3 signal transduction pathway in ADAMTS1-transduced HMVEC-dLy. Cell proliferation and tube formation in Matrigel were significantly lower with transduced ADAMTS1 than with control (non-transduced HMVEC-dLy). The phosphorylation of VEGFR3 was also attenuated by ADAMTS1 gene therapy in HMVEC-dLy. Immunoprecipitation assays revealed that ADAMTS1 formed a complex with VEGFC. Our results demonstrated that ADAMTS1 inhibited lymphangiogenesis in vitro. The data highlight the new function of ADAMTS1 in the regulation of lymphangiogenesis and the therapeutic potential of ADAMTS1 in cancer therapy. - Highlights: • ADAMTS1 significantly inhibited tube formation and cell proliferation in HMVEC-dLy. • Reduced lymph endothelial cell migration in ADAMTS1 transduced co-culture systems. • VEGFC-stimulated phosphorylation of VEGFR3 is attenuated by ADAMTS1. • Reduced phosphorylation of Akt and ERK1/2 in ADAMTS1 treated HMVEC-dLy. • ADAMTS1 binds directly to VEGFC.

  18. ADAMTS1 inhibits lymphangiogenesis by attenuating phosphorylation of the lymphatic endothelial cell-specific VEGF receptor

    International Nuclear Information System (INIS)

    Inagaki, Junko; Takahashi, Katsuyuki; Ogawa, Hiroko; Asano, Keiichi; Faruk Hatipoglu, Omer; Zeynel Cilek, Mehmet; Obika, Masanari; Ohtsuki, Takashi; Hofmann, Matthias; Kusachi, Shozo; Ninomiya, Yoshifumi; Hirohata, Satoshi

    2014-01-01

    Angiogenesis and lymphangiogenesis play roles in malignant tumor progression, dissemination, and metastasis. ADAMTS1, a member of the matrix metalloproteinase family, is known to inhibit angiogenesis. Recombinant ADAMTS1 was shown to strongly inhibit angiogenesis. We investigated whether ADAMTS1 inhibited lymphangiogenesis in the present study. We examined cell proliferation and cell migration in normal human dermal lymphatic microvascular endothelial cells (HMVEC-dLy) transduced with or without adenoviral human ADAMTS1 gene therapy. We then examined the VEGFC/VEGFR3 signal transduction pathway in ADAMTS1-transduced HMVEC-dLy. Cell proliferation and tube formation in Matrigel were significantly lower with transduced ADAMTS1 than with control (non-transduced HMVEC-dLy). The phosphorylation of VEGFR3 was also attenuated by ADAMTS1 gene therapy in HMVEC-dLy. Immunoprecipitation assays revealed that ADAMTS1 formed a complex with VEGFC. Our results demonstrated that ADAMTS1 inhibited lymphangiogenesis in vitro. The data highlight the new function of ADAMTS1 in the regulation of lymphangiogenesis and the therapeutic potential of ADAMTS1 in cancer therapy. - Highlights: • ADAMTS1 significantly inhibited tube formation and cell proliferation in HMVEC-dLy. • Reduced lymph endothelial cell migration in ADAMTS1 transduced co-culture systems. • VEGFC-stimulated phosphorylation of VEGFR3 is attenuated by ADAMTS1. • Reduced phosphorylation of Akt and ERK1/2 in ADAMTS1 treated HMVEC-dLy. • ADAMTS1 binds directly to VEGFC

  19. B7-H4 Treatment of T Cells Inhibits ERK, JNK, p38, and AKT Activation.

    Directory of Open Access Journals (Sweden)

    Xiaojie Wang

    Full Text Available B7-H4 is a newly identified B7 homolog that plays an important role in maintaining T-cell homeostasis by inhibiting T-cell proliferation and lymphokine-secretion. In this study, we investigated the signal transduction pathways inhibited by B7-H4 engagement in mouse T cells. We found that treatment of CD3(+ T cells with a B7-H4.Ig fusion protein inhibits anti-CD3 elicited T-cell receptor (TCR/CD28 signaling events, including phosphorylation of the MAP kinases, ERK, p38, and JNK. B7-H4.Ig treatment also inhibited the phosphorylation of AKT kinase and impaired its kinase activity as assessed by the phosphorylation of its endogenous substrate GSK-3. Expression of IL-2 is also reduced by B7-H4. In contrast, the phosphorylation state of the TCR proximal tyrosine kinases ZAP70 and lymphocyte-specific protein tyrosine kinase (LCK are not affected by B7-H4 ligation. These results indicate that B7-H4 inhibits T-cell proliferation and IL-2 production through interfering with activation of ERK, JNK, and AKT, but not of ZAP70 or LCK.

  20. The coffee diterpene kahweol inhibits tumor necrosis factor-α-induced expression of cell adhesion molecules in human endothelial cells

    International Nuclear Information System (INIS)

    Kim, Hyung Gyun; Kim, Ji Young; Hwang, Yong Pil; Lee, Kyung Jin; Lee, Kwang Youl; Kim, Dong Hee; Kim, Dong Hyun; Jeong, Hye Gwang

    2006-01-01

    Endothelial cells produce adhesion molecules after being stimulated with various inflammatory cytokines. These adhesion molecules play an important role in the development of atherogenesis. Recent studies have highlighted the chemoprotective and anti-inflammatory effects of kahweol, a coffee-specific diterpene. This study examined the effects of kahweol on the cytokine-induced monocyte/human endothelial cell interaction, which is a crucial early event in atherogenesis. Kahweol inhibited the adhesion of TNFα-induced monocytes to endothelial cells and suppressed the TNFα-induced protein and mRNA expression of the cell adhesion molecules, VCAM-1 and ICAM-1. Furthermore, kahweol inhibited the TNFα-induced JAK2-PI3K/Akt-NF-κB activation pathway in these cells. Overall, kahweol has anti-inflammatory and anti-atherosclerotic activities, which occurs partly by down-regulating the pathway that affects the expression and interaction of the cell adhesion molecules on endothelial cells

  1. Antioxidant and cytotoxic activity of new di- and polyamine caffeine analogues.

    Science.gov (United States)

    Jasiewicz, Beata; Sierakowska, Arleta; Jankowski, Wojciech; Hoffmann, Marcin; Piorońska, Weronika; Górnicka, Agnieszka; Bielawska, Anna; Bielawski, Krzysztof; Mrówczyńska, Lucyna

    2018-04-18

    A series of new di- and polyamine-caffeine analogues were synthesized and characterized by NMR, FT-IR and MS spectroscopic methods. To access stability of the investigated caffeine analogues Molecular Dynamic simulations were performed in NAMD 2.9 assuming CHARMM36 force field. To evaluate the antioxidant capacity of new compounds, three different antioxidant assays were used, namely 1,1-diphenyl-2-picryl-hydrazyl free radical (DPPH • ) scavenging activity, ferrous ions (Fe 2+ ) chelating activity and Fe 3+ →Fe 2+ reducing ability. In vitro, the ability of new derivatives to protect human erythrocytes against oxidative haemolysis induced by free radical from 2,2'-azobis(2-methylpropionamidine) dihydrochloride (AAPH) was estimated. The cytotoxic activity was tested using MCF-7 breast cancer cells and human erythrocytes. All compounds showed the antioxidant capacity depending mostly on their ferrous ions chelating activity. In the presence of AAPH, some derivatives were able to effectively inhibit the oxidative haemolysis. Two derivatives, namely 8-(methyl(2-(methylamino)ethyl)-amino)caffeine and 8-(methyl(3-(methylamino)propyl)amino)caffeine, showed cytotoxic activity against MCF-7 breast cancer cells but not against human erythrocytes. Therefore, it is concluded that the selected di- and polyamine caffeine analogues, depending on their chemical structure, were able to minimize the oxidative stress and to inhibit the tumour cell grow. The confirmed antioxidant and cytotoxic properties of some caffeine derivatives make them attractive for potential applications in food or pharmaceutical industries.

  2. Glyphosate and AMPA inhibit cancer cell growth through inhibiting intracellular glycine synthesis

    OpenAIRE

    Li, Qingli; Lambrechts, Mark J; Zhang, Qiuyang; Liu, Sen; Ge, Dongxia; Yin, Rutie; Xi, Mingrong; You, Zongbing

    2013-01-01

    Qingli Li,1,2 Mark J Lambrechts,1 Qiuyang Zhang,1 Sen Liu,1 Dongxia Ge,1 Rutie Yin,2 Mingrong Xi,2 Zongbing You1 1Departments of Structural and Cellular Biology and Orthopaedic Surgery, Tulane Cancer Center and Louisiana Cancer Research Consortium, Tulane Center for Stem Cell Research and Regenerative Medicine, and Tulane Center for Aging, Tulane University Health Sciences Center, New Orleans, LA, USA; 2Department of Obstetrics and Gynecology, West China Second University Hospital, Sichuan Un...

  3. Implication of unfolded protein response in resveratrol-induced inhibition of K562 cell proliferation

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Bao-Qin; Gao, Yan-Yan; Niu, Xiao-Fang [Department of Biochemistry and Molecular Biology, China Medical University, Shenyang 110001 (China); Xie, Ji-Sheng [Youjiang Medical College for Nationalities, Guangxi 533000 (China); Meng, Xin; Guan, Yifu [Department of Biochemistry and Molecular Biology, China Medical University, Shenyang 110001 (China); Wang, Hua-Qin, E-mail: wanghq_doctor@hotmail.com [Department of Biochemistry and Molecular Biology, China Medical University, Shenyang 110001 (China)

    2010-01-01

    Resveratrol (RES), a natural plant polyphenol, is an effective inducer of cell cycle arrest and apoptosis in a variety of carcinoma cell types. In addition, RES has been reported to inhibit tumorigenesis in several animal models suggesting that it functions as a chemopreventive and anti-tumor agent in vivo. The chemopreventive and chemotherapeutic properties associated with resveratrol offer promise for the design of new chemotherapeutic agents. However, the mechanisms by which RES mediates its effects are not yet fully understood. In this study, we showed that RES caused cell cycle arrest and proliferation inhibition via induction of unfolded protein response (UPR) in human leukemia K562 cell line. Treatment of K562 cells with RES induced a number of signature UPR markers, including transcriptional induction of GRP78 and CHOP, phosphorylation of eukaryotic initiation factor 2{alpha} (eIF2{alpha}), ER stress-specific XBP-1 splicing, suggesting the induction of UPR by RES. RES inhibited proliferation of K562 in a concentration-dependent manner. Flow cytometric analyses revealed that K562 cells were arrested in G1 phase upon RES treatment. Salubrinal, an eIF2{alpha} inhibitor, or overexpression of dominant negative mutants of PERK or eIF2{alpha}, effectively restored RES-induced cell cycle arrest, underscoring the important role of PERK/eIF2{alpha} branch of UPR in RES-induced inhibition of cell proliferation.

  4. Retinoid inhibition of in vitro invasion of human amnion basement membrane by human tumor cells

    International Nuclear Information System (INIS)

    Fazely, F.; Ledinko, N.; Smith, D.J.

    1986-0